drm/rockchip: add rk3399 vop big csc support

[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / drm_crtc.c

/*
 * Copyright (c) 2006-2008 Intel Corporation
 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
 * Copyright (c) 2008 Red Hat Inc.
 *
 * DRM core CRTC related functions
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that copyright
 * notice and this permission notice appear in supporting documentation, and
 * that the name of the copyright holders not be used in advertising or
 * publicity pertaining to distribution of the software without specific,
 * written prior permission.  The copyright holders make no representations
 * about the suitability of this software for any purpose.  It is provided "as
 * is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
 * OF THIS SOFTWARE.
 *
 * Authors:
 *      Keith Packard
 *      Eric Anholt <eric@anholt.net>
 *      Dave Airlie <airlied@linux.ie>
 *      Jesse Barnes <jesse.barnes@intel.com>
 */
#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <drm/drmP.h>
#include <drm/drm_crtc.h>
#include <drm/drm_edid.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_modeset_lock.h>
#include <drm/drm_atomic.h>

#include "drm_crtc_internal.h"
#include "drm_internal.h"

static struct drm_framebuffer *
internal_framebuffer_create(struct drm_device *dev,
                            struct drm_mode_fb_cmd2 *r,
                            struct drm_file *file_priv);

/* Avoid boilerplate.  I'm tired of typing. */
#define DRM_ENUM_NAME_FN(fnname, list)                          \
        const char *fnname(int val)                             \
        {                                                       \
                int i;                                          \
                for (i = 0; i < ARRAY_SIZE(list); i++) {        \
                        if (list[i].type == val)                \
                                return list[i].name;            \
                }                                               \
                return "(unknown)";                             \
        }

/*
 * Global properties
 */
static const struct drm_prop_enum_list drm_dpms_enum_list[] = {
        { DRM_MODE_DPMS_ON, "On" },
        { DRM_MODE_DPMS_STANDBY, "Standby" },
        { DRM_MODE_DPMS_SUSPEND, "Suspend" },
        { DRM_MODE_DPMS_OFF, "Off" }
};

DRM_ENUM_NAME_FN(drm_get_dpms_name, drm_dpms_enum_list)

static const struct drm_prop_enum_list drm_plane_type_enum_list[] = {
        { DRM_PLANE_TYPE_OVERLAY, "Overlay" },
        { DRM_PLANE_TYPE_PRIMARY, "Primary" },
        { DRM_PLANE_TYPE_CURSOR, "Cursor" },
};

/*
 * Optional properties
 */
static const struct drm_prop_enum_list drm_scaling_mode_enum_list[] = {
        { DRM_MODE_SCALE_NONE, "None" },
        { DRM_MODE_SCALE_FULLSCREEN, "Full" },
        { DRM_MODE_SCALE_CENTER, "Center" },
        { DRM_MODE_SCALE_ASPECT, "Full aspect" },
};

static const struct drm_prop_enum_list drm_aspect_ratio_enum_list[] = {
        { DRM_MODE_PICTURE_ASPECT_NONE, "Automatic" },
        { DRM_MODE_PICTURE_ASPECT_4_3, "4:3" },
        { DRM_MODE_PICTURE_ASPECT_16_9, "16:9" },
};

/*
 * Non-global properties, but "required" for certain connectors.
 */
static const struct drm_prop_enum_list drm_dvi_i_select_enum_list[] = {
        { DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
        { DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
};

DRM_ENUM_NAME_FN(drm_get_dvi_i_select_name, drm_dvi_i_select_enum_list)

static const struct drm_prop_enum_list drm_dvi_i_subconnector_enum_list[] = {
        { DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_DVID,      "DVI-D"     }, /* DVI-I  */
        { DRM_MODE_SUBCONNECTOR_DVIA,      "DVI-A"     }, /* DVI-I  */
};

DRM_ENUM_NAME_FN(drm_get_dvi_i_subconnector_name,
                 drm_dvi_i_subconnector_enum_list)

static const struct drm_prop_enum_list drm_tv_select_enum_list[] = {
        { DRM_MODE_SUBCONNECTOR_Automatic, "Automatic" }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
};

DRM_ENUM_NAME_FN(drm_get_tv_select_name, drm_tv_select_enum_list)

static const struct drm_prop_enum_list drm_tv_subconnector_enum_list[] = {
        { DRM_MODE_SUBCONNECTOR_Unknown,   "Unknown"   }, /* DVI-I and TV-out */
        { DRM_MODE_SUBCONNECTOR_Composite, "Composite" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SVIDEO,    "SVIDEO"    }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_Component, "Component" }, /* TV-out */
        { DRM_MODE_SUBCONNECTOR_SCART,     "SCART"     }, /* TV-out */
};

DRM_ENUM_NAME_FN(drm_get_tv_subconnector_name,
                 drm_tv_subconnector_enum_list)

static const struct drm_prop_enum_list drm_dirty_info_enum_list[] = {
        { DRM_MODE_DIRTY_OFF,      "Off"      },
        { DRM_MODE_DIRTY_ON,       "On"       },
        { DRM_MODE_DIRTY_ANNOTATE, "Annotate" },
};

struct drm_conn_prop_enum_list {
        int type;
        const char *name;
        struct ida ida;
};

/*
 * Connector and encoder types.
 */
static struct drm_conn_prop_enum_list drm_connector_enum_list[] = {
        { DRM_MODE_CONNECTOR_Unknown, "Unknown" },
        { DRM_MODE_CONNECTOR_VGA, "VGA" },
        { DRM_MODE_CONNECTOR_DVII, "DVI-I" },
        { DRM_MODE_CONNECTOR_DVID, "DVI-D" },
        { DRM_MODE_CONNECTOR_DVIA, "DVI-A" },
        { DRM_MODE_CONNECTOR_Composite, "Composite" },
        { DRM_MODE_CONNECTOR_SVIDEO, "SVIDEO" },
        { DRM_MODE_CONNECTOR_LVDS, "LVDS" },
        { DRM_MODE_CONNECTOR_Component, "Component" },
        { DRM_MODE_CONNECTOR_9PinDIN, "DIN" },
        { DRM_MODE_CONNECTOR_DisplayPort, "DP" },
        { DRM_MODE_CONNECTOR_HDMIA, "HDMI-A" },
        { DRM_MODE_CONNECTOR_HDMIB, "HDMI-B" },
        { DRM_MODE_CONNECTOR_TV, "TV" },
        { DRM_MODE_CONNECTOR_eDP, "eDP" },
        { DRM_MODE_CONNECTOR_VIRTUAL, "Virtual" },
        { DRM_MODE_CONNECTOR_DSI, "DSI" },
};

static const struct drm_prop_enum_list drm_encoder_enum_list[] = {
        { DRM_MODE_ENCODER_NONE, "None" },
        { DRM_MODE_ENCODER_DAC, "DAC" },
        { DRM_MODE_ENCODER_TMDS, "TMDS" },
        { DRM_MODE_ENCODER_LVDS, "LVDS" },
        { DRM_MODE_ENCODER_TVDAC, "TV" },
        { DRM_MODE_ENCODER_VIRTUAL, "Virtual" },
        { DRM_MODE_ENCODER_DSI, "DSI" },
        { DRM_MODE_ENCODER_DPMST, "DP MST" },
};

static const struct drm_prop_enum_list drm_subpixel_enum_list[] = {
        { SubPixelUnknown, "Unknown" },
        { SubPixelHorizontalRGB, "Horizontal RGB" },
        { SubPixelHorizontalBGR, "Horizontal BGR" },
        { SubPixelVerticalRGB, "Vertical RGB" },
        { SubPixelVerticalBGR, "Vertical BGR" },
        { SubPixelNone, "None" },
};

void drm_connector_ida_init(void)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
                ida_init(&drm_connector_enum_list[i].ida);
}

void drm_connector_ida_destroy(void)
{
        int i;

        for (i = 0; i < ARRAY_SIZE(drm_connector_enum_list); i++)
                ida_destroy(&drm_connector_enum_list[i].ida);
}

/**
 * drm_get_connector_status_name - return a string for connector status
 * @status: connector status to compute name of
 *
 * In contrast to the other drm_get_*_name functions this one here returns a
 * const pointer and hence is threadsafe.
 */
const char *drm_get_connector_status_name(enum drm_connector_status status)
{
        if (status == connector_status_connected)
                return "connected";
        else if (status == connector_status_disconnected)
                return "disconnected";
        else
                return "unknown";
}
EXPORT_SYMBOL(drm_get_connector_status_name);

/**
 * drm_get_subpixel_order_name - return a string for a given subpixel enum
 * @order: enum of subpixel_order
 *
 * Note you could abuse this and return something out of bounds, but that
 * would be a caller error.  No unscrubbed user data should make it here.
 */
const char *drm_get_subpixel_order_name(enum subpixel_order order)
{
        return drm_subpixel_enum_list[order].name;
}
EXPORT_SYMBOL(drm_get_subpixel_order_name);

static char printable_char(int c)
{
        return isascii(c) && isprint(c) ? c : '?';
}

/**
 * drm_get_format_name - return a string for drm fourcc format
 * @format: format to compute name of
 *
 * Note that the buffer used by this function is globally shared and owned by
 * the function itself.
 *
 * FIXME: This isn't really multithreading safe.
 */
const char *drm_get_format_name(uint32_t format)
{
        static char buf[32];

        snprintf(buf, sizeof(buf),
                 "%c%c%c%c %s-endian (0x%08x)",
                 printable_char(format & 0xff),
                 printable_char((format >> 8) & 0xff),
                 printable_char((format >> 16) & 0xff),
                 printable_char((format >> 24) & 0x7f),
                 format & DRM_FORMAT_BIG_ENDIAN ? "big" : "little",
                 format);

        return buf;
}
EXPORT_SYMBOL(drm_get_format_name);

/*
 * Internal function to assign a slot in the object idr and optionally
 * register the object into the idr.
 */
static int drm_mode_object_get_reg(struct drm_device *dev,
                                   struct drm_mode_object *obj,
                                   uint32_t obj_type,
                                   bool register_obj)
{
        int ret;

        mutex_lock(&dev->mode_config.idr_mutex);
        ret = idr_alloc(&dev->mode_config.crtc_idr, register_obj ? obj : NULL, 1, 0, GFP_KERNEL);
        if (ret >= 0) {
                /*
                 * Set up the object linking under the protection of the idr
                 * lock so that other users can't see inconsistent state.
                 */
                obj->id = ret;
                obj->type = obj_type;
        }
        mutex_unlock(&dev->mode_config.idr_mutex);

        return ret < 0 ? ret : 0;
}

/**
 * drm_mode_object_get - allocate a new modeset identifier
 * @dev: DRM device
 * @obj: object pointer, used to generate unique ID
 * @obj_type: object type
 *
 * Create a unique identifier based on @ptr in @dev's identifier space.  Used
 * for tracking modes, CRTCs and connectors. Note that despite the _get postfix
 * modeset identifiers are _not_ reference counted. Hence don't use this for
 * reference counted modeset objects like framebuffers.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_mode_object_get(struct drm_device *dev,
                        struct drm_mode_object *obj, uint32_t obj_type)
{
        return drm_mode_object_get_reg(dev, obj, obj_type, true);
}

static void drm_mode_object_register(struct drm_device *dev,
                                     struct drm_mode_object *obj)
{
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_replace(&dev->mode_config.crtc_idr, obj, obj->id);
        mutex_unlock(&dev->mode_config.idr_mutex);
}

/**
 * drm_mode_object_put - free a modeset identifer
 * @dev: DRM device
 * @object: object to free
 *
 * Free @id from @dev's unique identifier pool. Note that despite the _get
 * postfix modeset identifiers are _not_ reference counted. Hence don't use this
 * for reference counted modeset objects like framebuffers.
 */
void drm_mode_object_put(struct drm_device *dev,
                         struct drm_mode_object *object)
{
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_remove(&dev->mode_config.crtc_idr, object->id);
        mutex_unlock(&dev->mode_config.idr_mutex);
}

static struct drm_mode_object *_object_find(struct drm_device *dev,
                uint32_t id, uint32_t type)
{
        struct drm_mode_object *obj = NULL;

        mutex_lock(&dev->mode_config.idr_mutex);
        obj = idr_find(&dev->mode_config.crtc_idr, id);
        if (obj && type != DRM_MODE_OBJECT_ANY && obj->type != type)
                obj = NULL;
        if (obj && obj->id != id)
                obj = NULL;
        /* don't leak out unref'd fb's */
        if (obj &&
            (obj->type == DRM_MODE_OBJECT_FB ||
             obj->type == DRM_MODE_OBJECT_BLOB))
                obj = NULL;
        mutex_unlock(&dev->mode_config.idr_mutex);

        return obj;
}

/**
 * drm_mode_object_find - look up a drm object with static lifetime
 * @dev: drm device
 * @id: id of the mode object
 * @type: type of the mode object
 *
 * Note that framebuffers cannot be looked up with this functions - since those
 * are reference counted, they need special treatment.  Even with
 * DRM_MODE_OBJECT_ANY (although that will simply return NULL
 * rather than WARN_ON()).
 */
struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
                uint32_t id, uint32_t type)
{
        struct drm_mode_object *obj = NULL;

        /* Framebuffers are reference counted and need their own lookup
         * function.*/
        WARN_ON(type == DRM_MODE_OBJECT_FB || type == DRM_MODE_OBJECT_BLOB);
        obj = _object_find(dev, id, type);
        return obj;
}
EXPORT_SYMBOL(drm_mode_object_find);

/**
 * drm_framebuffer_init - initialize a framebuffer
 * @dev: DRM device
 * @fb: framebuffer to be initialized
 * @funcs: ... with these functions
 *
 * Allocates an ID for the framebuffer's parent mode object, sets its mode
 * functions & device file and adds it to the master fd list.
 *
 * IMPORTANT:
 * This functions publishes the fb and makes it available for concurrent access
 * by other users. Which means by this point the fb _must_ be fully set up -
 * since all the fb attributes are invariant over its lifetime, no further
 * locking but only correct reference counting is required.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
                         const struct drm_framebuffer_funcs *funcs)
{
        int ret;

        mutex_lock(&dev->mode_config.fb_lock);
        kref_init(&fb->refcount);
        INIT_LIST_HEAD(&fb->filp_head);
        fb->dev = dev;
        fb->funcs = funcs;

        ret = drm_mode_object_get(dev, &fb->base, DRM_MODE_OBJECT_FB);
        if (ret)
                goto out;

        dev->mode_config.num_fb++;
        list_add(&fb->head, &dev->mode_config.fb_list);
out:
        mutex_unlock(&dev->mode_config.fb_lock);

        return ret;
}
EXPORT_SYMBOL(drm_framebuffer_init);

/* dev->mode_config.fb_lock must be held! */
static void __drm_framebuffer_unregister(struct drm_device *dev,
                                         struct drm_framebuffer *fb)
{
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_remove(&dev->mode_config.crtc_idr, fb->base.id);
        mutex_unlock(&dev->mode_config.idr_mutex);

        fb->base.id = 0;
}

static void drm_framebuffer_free(struct kref *kref)
{
        struct drm_framebuffer *fb =
                        container_of(kref, struct drm_framebuffer, refcount);
        struct drm_device *dev = fb->dev;

        /*
         * The lookup idr holds a weak reference, which has not necessarily been
         * removed at this point. Check for that.
         */
        mutex_lock(&dev->mode_config.fb_lock);
        if (fb->base.id) {
                /* Mark fb as reaped and drop idr ref. */
                __drm_framebuffer_unregister(dev, fb);
        }
        mutex_unlock(&dev->mode_config.fb_lock);

        fb->funcs->destroy(fb);
}

static struct drm_framebuffer *__drm_framebuffer_lookup(struct drm_device *dev,
                                                        uint32_t id)
{
        struct drm_mode_object *obj = NULL;
        struct drm_framebuffer *fb;

        mutex_lock(&dev->mode_config.idr_mutex);
        obj = idr_find(&dev->mode_config.crtc_idr, id);
        if (!obj || (obj->type != DRM_MODE_OBJECT_FB) || (obj->id != id))
                fb = NULL;
        else
                fb = obj_to_fb(obj);
        mutex_unlock(&dev->mode_config.idr_mutex);

        return fb;
}

/**
 * drm_framebuffer_lookup - look up a drm framebuffer and grab a reference
 * @dev: drm device
 * @id: id of the fb object
 *
 * If successful, this grabs an additional reference to the framebuffer -
 * callers need to make sure to eventually unreference the returned framebuffer
 * again, using @drm_framebuffer_unreference.
 */
struct drm_framebuffer *drm_framebuffer_lookup(struct drm_device *dev,
                                               uint32_t id)
{
        struct drm_framebuffer *fb;

        mutex_lock(&dev->mode_config.fb_lock);
        fb = __drm_framebuffer_lookup(dev, id);
        if (fb) {
                if (!kref_get_unless_zero(&fb->refcount))
                        fb = NULL;
        }
        mutex_unlock(&dev->mode_config.fb_lock);

        return fb;
}
EXPORT_SYMBOL(drm_framebuffer_lookup);

/**
 * drm_framebuffer_unreference - unref a framebuffer
 * @fb: framebuffer to unref
 *
 * This functions decrements the fb's refcount and frees it if it drops to zero.
 */
void drm_framebuffer_unreference(struct drm_framebuffer *fb)
{
        DRM_DEBUG("%p: FB ID: %d (%d)\n", fb, fb->base.id, atomic_read(&fb->refcount.refcount));
        kref_put(&fb->refcount, drm_framebuffer_free);
}
EXPORT_SYMBOL(drm_framebuffer_unreference);

/**
 * drm_framebuffer_reference - incr the fb refcnt
 * @fb: framebuffer
 *
 * This functions increments the fb's refcount.
 */
void drm_framebuffer_reference(struct drm_framebuffer *fb)
{
        DRM_DEBUG("%p: FB ID: %d (%d)\n", fb, fb->base.id, atomic_read(&fb->refcount.refcount));
        kref_get(&fb->refcount);
}
EXPORT_SYMBOL(drm_framebuffer_reference);

/**
 * drm_framebuffer_unregister_private - unregister a private fb from the lookup idr
 * @fb: fb to unregister
 *
 * Drivers need to call this when cleaning up driver-private framebuffers, e.g.
 * those used for fbdev. Note that the caller must hold a reference of it's own,
 * i.e. the object may not be destroyed through this call (since it'll lead to a
 * locking inversion).
 */
void drm_framebuffer_unregister_private(struct drm_framebuffer *fb)
{
        struct drm_device *dev;

        if (!fb)
                return;

        dev = fb->dev;

        mutex_lock(&dev->mode_config.fb_lock);
        /* Mark fb as reaped and drop idr ref. */
        __drm_framebuffer_unregister(dev, fb);
        mutex_unlock(&dev->mode_config.fb_lock);
}
EXPORT_SYMBOL(drm_framebuffer_unregister_private);

/**
 * drm_framebuffer_cleanup - remove a framebuffer object
 * @fb: framebuffer to remove
 *
 * Cleanup framebuffer. This function is intended to be used from the drivers
 * ->destroy callback. It can also be used to clean up driver private
 *  framebuffers embedded into a larger structure.
 *
 * Note that this function does not remove the fb from active usuage - if it is
 * still used anywhere, hilarity can ensue since userspace could call getfb on
 * the id and get back -EINVAL. Obviously no concern at driver unload time.
 *
 * Also, the framebuffer will not be removed from the lookup idr - for
 * user-created framebuffers this will happen in in the rmfb ioctl. For
 * driver-private objects (e.g. for fbdev) drivers need to explicitly call
 * drm_framebuffer_unregister_private.
 */
void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
{
        struct drm_device *dev = fb->dev;

        mutex_lock(&dev->mode_config.fb_lock);
        list_del(&fb->head);
        dev->mode_config.num_fb--;
        mutex_unlock(&dev->mode_config.fb_lock);
}
EXPORT_SYMBOL(drm_framebuffer_cleanup);

/**
 * drm_framebuffer_remove - remove and unreference a framebuffer object
 * @fb: framebuffer to remove
 *
 * Scans all the CRTCs and planes in @dev's mode_config.  If they're
 * using @fb, removes it, setting it to NULL. Then drops the reference to the
 * passed-in framebuffer. Might take the modeset locks.
 *
 * Note that this function optimizes the cleanup away if the caller holds the
 * last reference to the framebuffer. It is also guaranteed to not take the
 * modeset locks in this case.
 */
void drm_framebuffer_remove(struct drm_framebuffer *fb)
{
        struct drm_device *dev;
        struct drm_crtc *crtc;
        struct drm_plane *plane;
        struct drm_mode_set set;
        int ret;

        if (!fb)
                return;

        dev = fb->dev;

        WARN_ON(!list_empty(&fb->filp_head));

        /*
         * drm ABI mandates that we remove any deleted framebuffers from active
         * useage. But since most sane clients only remove framebuffers they no
         * longer need, try to optimize this away.
         *
         * Since we're holding a reference ourselves, observing a refcount of 1
         * means that we're the last holder and can skip it. Also, the refcount
         * can never increase from 1 again, so we don't need any barriers or
         * locks.
         *
         * Note that userspace could try to race with use and instate a new
         * usage _after_ we've cleared all current ones. End result will be an
         * in-use fb with fb-id == 0. Userspace is allowed to shoot its own foot
         * in this manner.
         */
        if (atomic_read(&fb->refcount.refcount) > 1) {
                drm_modeset_lock_all(dev);
                /* remove from any CRTC */
                drm_for_each_crtc(crtc, dev) {
                        if (crtc->primary->fb == fb) {
                                /* should turn off the crtc */
                                memset(&set, 0, sizeof(struct drm_mode_set));
                                set.crtc = crtc;
                                set.fb = NULL;
                                ret = drm_mode_set_config_internal(&set);
                                if (ret)
                                        DRM_ERROR("failed to reset crtc %p when fb was deleted\n", crtc);
                        }
                }

                drm_for_each_plane(plane, dev) {
                        if (plane->fb == fb)
                                drm_plane_force_disable(plane);
                }
                drm_modeset_unlock_all(dev);
        }

        drm_framebuffer_unreference(fb);
}
EXPORT_SYMBOL(drm_framebuffer_remove);

DEFINE_WW_CLASS(crtc_ww_class);

/**
 * drm_crtc_init_with_planes - Initialise a new CRTC object with
 *    specified primary and cursor planes.
 * @dev: DRM device
 * @crtc: CRTC object to init
 * @primary: Primary plane for CRTC
 * @cursor: Cursor plane for CRTC
 * @funcs: callbacks for the new CRTC
 * @name: printf style format string for the CRTC name, or NULL for default name
 *
 * Inits a new object created as base part of a driver crtc object.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
                              struct drm_plane *primary,
                              struct drm_plane *cursor,
                              const struct drm_crtc_funcs *funcs,
                              const char *name, ...)
{
        struct drm_mode_config *config = &dev->mode_config;
        int ret;

        WARN_ON(primary && primary->type != DRM_PLANE_TYPE_PRIMARY);
        WARN_ON(cursor && cursor->type != DRM_PLANE_TYPE_CURSOR);

        crtc->dev = dev;
        crtc->funcs = funcs;

        drm_modeset_lock_init(&crtc->mutex);
        ret = drm_mode_object_get(dev, &crtc->base, DRM_MODE_OBJECT_CRTC);
        if (ret)
                return ret;

        crtc->base.properties = &crtc->properties;

        list_add_tail(&crtc->head, &config->crtc_list);
        config->num_crtc++;

        crtc->primary = primary;
        crtc->cursor = cursor;
        if (primary)
                primary->possible_crtcs = 1 << drm_crtc_index(crtc);
        if (cursor)
                cursor->possible_crtcs = 1 << drm_crtc_index(crtc);

        if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
                drm_object_attach_property(&crtc->base, config->prop_active, 0);
                drm_object_attach_property(&crtc->base, config->prop_mode_id, 0);
        }

        return 0;
}
EXPORT_SYMBOL(drm_crtc_init_with_planes);

/**
 * drm_crtc_cleanup - Clean up the core crtc usage
 * @crtc: CRTC to cleanup
 *
 * This function cleans up @crtc and removes it from the DRM mode setting
 * core. Note that the function does *not* free the crtc structure itself,
 * this is the responsibility of the caller.
 */
void drm_crtc_cleanup(struct drm_crtc *crtc)
{
        struct drm_device *dev = crtc->dev;

        kfree(crtc->gamma_store);
        crtc->gamma_store = NULL;

        drm_modeset_lock_fini(&crtc->mutex);

        drm_mode_object_put(dev, &crtc->base);
        list_del(&crtc->head);
        dev->mode_config.num_crtc--;

        WARN_ON(crtc->state && !crtc->funcs->atomic_destroy_state);
        if (crtc->state && crtc->funcs->atomic_destroy_state)
                crtc->funcs->atomic_destroy_state(crtc, crtc->state);

        memset(crtc, 0, sizeof(*crtc));
}
EXPORT_SYMBOL(drm_crtc_cleanup);

/**
 * drm_crtc_index - find the index of a registered CRTC
 * @crtc: CRTC to find index for
 *
 * Given a registered CRTC, return the index of that CRTC within a DRM
 * device's list of CRTCs.
 */
unsigned int drm_crtc_index(struct drm_crtc *crtc)
{
        unsigned int index = 0;
        struct drm_crtc *tmp;

        drm_for_each_crtc(tmp, crtc->dev) {
                if (tmp == crtc)
                        return index;

                index++;
        }

        BUG();
}
EXPORT_SYMBOL(drm_crtc_index);

/*
 * drm_mode_remove - remove and free a mode
 * @connector: connector list to modify
 * @mode: mode to remove
 *
 * Remove @mode from @connector's mode list, then free it.
 */
static void drm_mode_remove(struct drm_connector *connector,
                            struct drm_display_mode *mode)
{
        list_del(&mode->head);
        drm_mode_destroy(connector->dev, mode);
}

/**
 * drm_display_info_set_bus_formats - set the supported bus formats
 * @info: display info to store bus formats in
 * @formats: array containing the supported bus formats
 * @num_formats: the number of entries in the fmts array
 *
 * Store the supported bus formats in display info structure.
 * See MEDIA_BUS_FMT_* definitions in include/uapi/linux/media-bus-format.h for
 * a full list of available formats.
 */
int drm_display_info_set_bus_formats(struct drm_display_info *info,
                                     const u32 *formats,
                                     unsigned int num_formats)
{
        u32 *fmts = NULL;

        if (!formats && num_formats)
                return -EINVAL;

        if (formats && num_formats) {
                fmts = kmemdup(formats, sizeof(*formats) * num_formats,
                               GFP_KERNEL);
                if (!fmts)
                        return -ENOMEM;
        }

        kfree(info->bus_formats);
        info->bus_formats = fmts;
        info->num_bus_formats = num_formats;

        return 0;
}
EXPORT_SYMBOL(drm_display_info_set_bus_formats);

/**
 * drm_connector_get_cmdline_mode - reads the user's cmdline mode
 * @connector: connector to quwery
 *
 * The kernel supports per-connector configration of its consoles through
 * use of the video= parameter. This function parses that option and
 * extracts the user's specified mode (or enable/disable status) for a
 * particular connector. This is typically only used during the early fbdev
 * setup.
 */
static void drm_connector_get_cmdline_mode(struct drm_connector *connector)
{
        struct drm_cmdline_mode *mode = &connector->cmdline_mode;
        char *option = NULL;

        if (fb_get_options(connector->name, &option))
                return;

        if (!drm_mode_parse_command_line_for_connector(option,
                                                       connector,
                                                       mode))
                return;

        if (mode->force) {
                const char *s;

                switch (mode->force) {
                case DRM_FORCE_OFF:
                        s = "OFF";
                        break;
                case DRM_FORCE_ON_DIGITAL:
                        s = "ON - dig";
                        break;
                default:
                case DRM_FORCE_ON:
                        s = "ON";
                        break;
                }

                DRM_INFO("forcing %s connector %s\n", connector->name, s);
                connector->force = mode->force;
        }

        DRM_DEBUG_KMS("cmdline mode for connector %s %dx%d@%dHz%s%s%s\n",
                      connector->name,
                      mode->xres, mode->yres,
                      mode->refresh_specified ? mode->refresh : 60,
                      mode->rb ? " reduced blanking" : "",
                      mode->margins ? " with margins" : "",
                      mode->interlace ?  " interlaced" : "");
}

/**
 * drm_connector_init - Init a preallocated connector
 * @dev: DRM device
 * @connector: the connector to init
 * @funcs: callbacks for this connector
 * @connector_type: user visible type of the connector
 *
 * Initialises a preallocated connector. Connectors should be
 * subclassed as part of driver connector objects.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_connector_init(struct drm_device *dev,
                       struct drm_connector *connector,
                       const struct drm_connector_funcs *funcs,
                       int connector_type)
{
        struct drm_mode_config *config = &dev->mode_config;
        int ret;
        struct ida *connector_ida =
                &drm_connector_enum_list[connector_type].ida;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get_reg(dev, &connector->base, DRM_MODE_OBJECT_CONNECTOR, false);
        if (ret)
                goto out_unlock;

        connector->base.properties = &connector->properties;
        connector->dev = dev;
        connector->funcs = funcs;
        connector->connector_type = connector_type;
        connector->connector_type_id =
                ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
        if (connector->connector_type_id < 0) {
                ret = connector->connector_type_id;
                goto out_put;
        }
        connector->name =
                kasprintf(GFP_KERNEL, "%s-%d",
                          drm_connector_enum_list[connector_type].name,
                          connector->connector_type_id);
        if (!connector->name) {
                ret = -ENOMEM;
                goto out_put;
        }

        INIT_LIST_HEAD(&connector->probed_modes);
        INIT_LIST_HEAD(&connector->modes);
        connector->edid_blob_ptr = NULL;
        connector->status = connector_status_unknown;

        drm_connector_get_cmdline_mode(connector);

        /* We should add connectors at the end to avoid upsetting the connector
         * index too much. */
        list_add_tail(&connector->head, &config->connector_list);
        config->num_connector++;

        if (connector_type != DRM_MODE_CONNECTOR_VIRTUAL)
                drm_object_attach_property(&connector->base,
                                              config->edid_property,
                                              0);

        drm_object_attach_property(&connector->base,
                                      config->dpms_property, 0);

        if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
                drm_object_attach_property(&connector->base, config->prop_crtc_id, 0);
        }

        connector->debugfs_entry = NULL;

out_put:
        if (ret)
                drm_mode_object_put(dev, &connector->base);

out_unlock:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_connector_init);

/**
 * drm_connector_cleanup - cleans up an initialised connector
 * @connector: connector to cleanup
 *
 * Cleans up the connector but doesn't free the object.
 */
void drm_connector_cleanup(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        struct drm_display_mode *mode, *t;

        if (connector->tile_group) {
                drm_mode_put_tile_group(dev, connector->tile_group);
                connector->tile_group = NULL;
        }

        list_for_each_entry_safe(mode, t, &connector->probed_modes, head)
                drm_mode_remove(connector, mode);

        list_for_each_entry_safe(mode, t, &connector->modes, head)
                drm_mode_remove(connector, mode);

        ida_remove(&drm_connector_enum_list[connector->connector_type].ida,
                   connector->connector_type_id);

        kfree(connector->display_info.bus_formats);
        drm_mode_object_put(dev, &connector->base);
        kfree(connector->name);
        connector->name = NULL;
        list_del(&connector->head);
        dev->mode_config.num_connector--;

        WARN_ON(connector->state && !connector->funcs->atomic_destroy_state);
        if (connector->state && connector->funcs->atomic_destroy_state)
                connector->funcs->atomic_destroy_state(connector,
                                                       connector->state);

        memset(connector, 0, sizeof(*connector));
}
EXPORT_SYMBOL(drm_connector_cleanup);

/**
 * drm_connector_index - find the index of a registered connector
 * @connector: connector to find index for
 *
 * Given a registered connector, return the index of that connector within a DRM
 * device's list of connectors.
 */
unsigned int drm_connector_index(struct drm_connector *connector)
{
        unsigned int index = 0;
        struct drm_connector *tmp;
        struct drm_mode_config *config = &connector->dev->mode_config;

        WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));

        drm_for_each_connector(tmp, connector->dev) {
                if (tmp == connector)
                        return index;

                index++;
        }

        BUG();
}
EXPORT_SYMBOL(drm_connector_index);

/**
 * drm_connector_register - register a connector
 * @connector: the connector to register
 *
 * Register userspace interfaces for a connector
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_connector_register(struct drm_connector *connector)
{
        int ret;

        drm_mode_object_register(connector->dev, &connector->base);

        ret = drm_sysfs_connector_add(connector);
        if (ret)
                return ret;

        ret = drm_debugfs_connector_add(connector);
        if (ret) {
                drm_sysfs_connector_remove(connector);
                return ret;
        }

        return 0;
}
EXPORT_SYMBOL(drm_connector_register);

/**
 * drm_connector_unregister - unregister a connector
 * @connector: the connector to unregister
 *
 * Unregister userspace interfaces for a connector
 */
void drm_connector_unregister(struct drm_connector *connector)
{
        drm_sysfs_connector_remove(connector);
        drm_debugfs_connector_remove(connector);
}
EXPORT_SYMBOL(drm_connector_unregister);


/**
 * drm_connector_unplug_all - unregister connector userspace interfaces
 * @dev: drm device
 *
 * This function unregisters all connector userspace interfaces in sysfs. Should
 * be call when the device is disconnected, e.g. from an usb driver's
 * ->disconnect callback.
 */
void drm_connector_unplug_all(struct drm_device *dev)
{
        struct drm_connector *connector;

        /* FIXME: taking the mode config mutex ends up in a clash with sysfs */
        list_for_each_entry(connector, &dev->mode_config.connector_list, head)
                drm_connector_unregister(connector);

}
EXPORT_SYMBOL(drm_connector_unplug_all);

/**
 * drm_encoder_init - Init a preallocated encoder
 * @dev: drm device
 * @encoder: the encoder to init
 * @funcs: callbacks for this encoder
 * @encoder_type: user visible type of the encoder
 * @name: printf style format string for the encoder name, or NULL for default name
 *
 * Initialises a preallocated encoder. Encoder should be
 * subclassed as part of driver encoder objects.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_encoder_init(struct drm_device *dev,
                      struct drm_encoder *encoder,
                      const struct drm_encoder_funcs *funcs,
                      int encoder_type, const char *name, ...)
{
        int ret;

        drm_modeset_lock_all(dev);

        ret = drm_mode_object_get(dev, &encoder->base, DRM_MODE_OBJECT_ENCODER);
        if (ret)
                goto out_unlock;

        encoder->dev = dev;
        encoder->encoder_type = encoder_type;
        encoder->funcs = funcs;
        encoder->name = kasprintf(GFP_KERNEL, "%s-%d",
                                  drm_encoder_enum_list[encoder_type].name,
                                  encoder->base.id);
        if (!encoder->name) {
                ret = -ENOMEM;
                goto out_put;
        }

        list_add_tail(&encoder->head, &dev->mode_config.encoder_list);
        dev->mode_config.num_encoder++;

out_put:
        if (ret)
                drm_mode_object_put(dev, &encoder->base);

out_unlock:
        drm_modeset_unlock_all(dev);

        return ret;
}
EXPORT_SYMBOL(drm_encoder_init);

/**
 * drm_encoder_cleanup - cleans up an initialised encoder
 * @encoder: encoder to cleanup
 *
 * Cleans up the encoder but doesn't free the object.
 */
void drm_encoder_cleanup(struct drm_encoder *encoder)
{
        struct drm_device *dev = encoder->dev;

        drm_modeset_lock_all(dev);
        drm_mode_object_put(dev, &encoder->base);
        kfree(encoder->name);
        list_del(&encoder->head);
        dev->mode_config.num_encoder--;
        drm_modeset_unlock_all(dev);

        memset(encoder, 0, sizeof(*encoder));
}
EXPORT_SYMBOL(drm_encoder_cleanup);

/**
 * drm_universal_plane_init - Initialize a new universal plane object
 * @dev: DRM device
 * @plane: plane object to init
 * @possible_crtcs: bitmask of possible CRTCs
 * @funcs: callbacks for the new plane
 * @formats: array of supported formats (%DRM_FORMAT_*)
 * @format_count: number of elements in @formats
 * @type: type of plane (overlay, primary, cursor)
 * @name: printf style format string for the plane name, or NULL for default name
 *
 * Initializes a plane object of type @type.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_universal_plane_init(struct drm_device *dev, struct drm_plane *plane,
                             unsigned long possible_crtcs,
                             const struct drm_plane_funcs *funcs,
                             const uint32_t *formats, unsigned int format_count,
                             enum drm_plane_type type,
                             const char *name, ...)
{
        struct drm_mode_config *config = &dev->mode_config;
        int ret;

        ret = drm_mode_object_get(dev, &plane->base, DRM_MODE_OBJECT_PLANE);
        if (ret)
                return ret;

        drm_modeset_lock_init(&plane->mutex);

        plane->base.properties = &plane->properties;
        plane->dev = dev;
        plane->funcs = funcs;
        plane->format_types = kmalloc_array(format_count, sizeof(uint32_t),
                                            GFP_KERNEL);
        if (!plane->format_types) {
                DRM_DEBUG_KMS("out of memory when allocating plane\n");
                drm_mode_object_put(dev, &plane->base);
                return -ENOMEM;
        }

        memcpy(plane->format_types, formats, format_count * sizeof(uint32_t));
        plane->format_count = format_count;
        plane->possible_crtcs = possible_crtcs;
        plane->type = type;

        list_add_tail(&plane->head, &config->plane_list);
        config->num_total_plane++;
        if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                config->num_overlay_plane++;

        drm_object_attach_property(&plane->base,
                                   config->plane_type_property,
                                   plane->type);

        if (drm_core_check_feature(dev, DRIVER_ATOMIC)) {
                drm_object_attach_property(&plane->base, config->prop_fb_id, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_id, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_x, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_y, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_w, 0);
                drm_object_attach_property(&plane->base, config->prop_crtc_h, 0);
                drm_object_attach_property(&plane->base, config->prop_src_x, 0);
                drm_object_attach_property(&plane->base, config->prop_src_y, 0);
                drm_object_attach_property(&plane->base, config->prop_src_w, 0);
                drm_object_attach_property(&plane->base, config->prop_src_h, 0);
        }

        return 0;
}
EXPORT_SYMBOL(drm_universal_plane_init);

/**
 * drm_plane_init - Initialize a legacy plane
 * @dev: DRM device
 * @plane: plane object to init
 * @possible_crtcs: bitmask of possible CRTCs
 * @funcs: callbacks for the new plane
 * @formats: array of supported formats (%DRM_FORMAT_*)
 * @format_count: number of elements in @formats
 * @is_primary: plane type (primary vs overlay)
 *
 * Legacy API to initialize a DRM plane.
 *
 * New drivers should call drm_universal_plane_init() instead.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_plane_init(struct drm_device *dev, struct drm_plane *plane,
                   unsigned long possible_crtcs,
                   const struct drm_plane_funcs *funcs,
                   const uint32_t *formats, unsigned int format_count,
                   bool is_primary)
{
        enum drm_plane_type type;

        type = is_primary ? DRM_PLANE_TYPE_PRIMARY : DRM_PLANE_TYPE_OVERLAY;
        return drm_universal_plane_init(dev, plane, possible_crtcs, funcs,
                                        formats, format_count, type, NULL);
}
EXPORT_SYMBOL(drm_plane_init);

/**
 * drm_share_plane_init - Initialize a share plane
 * @dev: DRM device
 * @plane: plane object to init
 * @parent: this plane share some resources with parent plane.
 * @possible_crtcs: bitmask of possible CRTCs
 * @funcs: callbacks for the new plane
 * @formats: array of supported formats (%DRM_FORMAT_*)
 * @format_count: number of elements in @formats
 * @type: type of plane (overlay, primary, cursor)
 *
 * With this API, the plane can share hardware resources with other planes.
 *
 *   --------------------------------------------------
 *   |  scanout                                       |
 *   |         ------------------                     |
 *   |         |  parent plane  |                     |
 *   |         | active scanout |                     |
 *   |         |                |   ----------------- |
 *   |         ------------------   | share plane 1 | |
 *   |  -----------------           |active scanout | |
 *   |  | share plane 0 |           |               | |
 *   |  |active scanout |           ----------------- |
 *   |  |               |                             |
 *   |  -----------------                             |
 *   --------------------------------------------------
 *
 *    parent plane
 *        |---share plane 0
 *        |---share plane 1
 *        ...
 *
 * The plane hardware is used when the display scanout run into plane active
 * scanout, that means we can reuse the plane hardware resources on plane
 * non-active scanout.
 *
 * Because resource share, There are some limit on share plane: one group
 * of share planes need use same zpos, can't not overlap, etc.
 *
 * Here assume share plane is a universal plane with some limit flags.
 * people who use the share plane need know the limit, should call the ioctl
 * DRM_CLIENT_CAP_SHARE_PLANES, and judge the planes limit before use it.
 *
 * Returns:
 * Zero on success, error code on failure.
 */

int drm_share_plane_init(struct drm_device *dev, struct drm_plane *plane,
                         struct drm_plane *parent,
                         unsigned long possible_crtcs,
                         const struct drm_plane_funcs *funcs,
                         const uint32_t *formats, unsigned int format_count,
                         enum drm_plane_type type)
{
        struct drm_mode_config *config = &dev->mode_config;
        int ret;
        int share_id;

        /*
         * TODO: only verified on ATOMIC drm driver.
         */
        if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
                return -EINVAL;

        ret = drm_universal_plane_init(dev, plane, possible_crtcs, funcs,
                                       formats, format_count, type, NULL);
        if (ret)
                return ret;

        if (parent) {
                /*
                 * Can't support more than two level plane share.
                 */
                WARN_ON(parent->parent);
                share_id = parent->base.id;
                plane->parent = parent;

                config->num_share_plane++;
                if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                        config->num_share_overlay_plane++;
        } else {
                share_id = plane->base.id;
        }

        drm_object_attach_property(&plane->base,
                                   config->prop_share_id, share_id);
        return 0;
}
EXPORT_SYMBOL(drm_share_plane_init);

/**
 * drm_plane_cleanup - Clean up the core plane usage
 * @plane: plane to cleanup
 *
 * This function cleans up @plane and removes it from the DRM mode setting
 * core. Note that the function does *not* free the plane structure itself,
 * this is the responsibility of the caller.
 */
void drm_plane_cleanup(struct drm_plane *plane)
{
        struct drm_device *dev = plane->dev;

        drm_modeset_lock_all(dev);
        kfree(plane->format_types);
        drm_mode_object_put(dev, &plane->base);

        BUG_ON(list_empty(&plane->head));

        list_del(&plane->head);
        dev->mode_config.num_total_plane--;
        if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                dev->mode_config.num_overlay_plane--;
        if (plane->parent) {
                dev->mode_config.num_share_plane--;
                if (plane->type == DRM_PLANE_TYPE_OVERLAY)
                        dev->mode_config.num_share_overlay_plane--;
        }
        drm_modeset_unlock_all(dev);

        WARN_ON(plane->state && !plane->funcs->atomic_destroy_state);
        if (plane->state && plane->funcs->atomic_destroy_state)
                plane->funcs->atomic_destroy_state(plane, plane->state);

        memset(plane, 0, sizeof(*plane));
}
EXPORT_SYMBOL(drm_plane_cleanup);

/**
 * drm_plane_index - find the index of a registered plane
 * @plane: plane to find index for
 *
 * Given a registered plane, return the index of that CRTC within a DRM
 * device's list of planes.
 */
unsigned int drm_plane_index(struct drm_plane *plane)
{
        unsigned int index = 0;
        struct drm_plane *tmp;

        drm_for_each_plane(tmp, plane->dev) {
                if (tmp == plane)
                        return index;

                index++;
        }

        BUG();
}
EXPORT_SYMBOL(drm_plane_index);

/**
 * drm_plane_from_index - find the registered plane at an index
 * @dev: DRM device
 * @idx: index of registered plane to find for
 *
 * Given a plane index, return the registered plane from DRM device's
 * list of planes with matching index.
 */
struct drm_plane *
drm_plane_from_index(struct drm_device *dev, int idx)
{
        struct drm_plane *plane;
        unsigned int i = 0;

        drm_for_each_plane(plane, dev) {
                if (i == idx)
                        return plane;
                i++;
        }
        return NULL;
}
EXPORT_SYMBOL(drm_plane_from_index);

/**
 * drm_plane_force_disable - Forcibly disable a plane
 * @plane: plane to disable
 *
 * Forces the plane to be disabled.
 *
 * Used when the plane's current framebuffer is destroyed,
 * and when restoring fbdev mode.
 */
void drm_plane_force_disable(struct drm_plane *plane)
{
        int ret;

        if (!plane->fb)
                return;

        plane->old_fb = plane->fb;
        ret = plane->funcs->disable_plane(plane);
        if (ret) {
                DRM_ERROR("failed to disable plane with busy fb\n");
                plane->old_fb = NULL;
                return;
        }
        /* disconnect the plane from the fb and crtc: */
        drm_framebuffer_unreference(plane->old_fb);
        plane->old_fb = NULL;
        plane->fb = NULL;
        plane->crtc = NULL;
}
EXPORT_SYMBOL(drm_plane_force_disable);

static int drm_mode_create_standard_properties(struct drm_device *dev)
{
        struct drm_property *prop;

        /*
         * Standard properties (apply to all connectors)
         */
        prop = drm_property_create(dev, DRM_MODE_PROP_BLOB |
                                   DRM_MODE_PROP_IMMUTABLE,
                                   "EDID", 0);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.edid_property = prop;

        prop = drm_property_create_enum(dev, 0,
                                   "DPMS", drm_dpms_enum_list,
                                   ARRAY_SIZE(drm_dpms_enum_list));
        if (!prop)
                return -ENOMEM;
        dev->mode_config.dpms_property = prop;

        prop = drm_property_create(dev,
                                   DRM_MODE_PROP_BLOB |
                                   DRM_MODE_PROP_IMMUTABLE,
                                   "PATH", 0);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.path_property = prop;

        prop = drm_property_create(dev,
                                   DRM_MODE_PROP_BLOB |
                                   DRM_MODE_PROP_IMMUTABLE,
                                   "TILE", 0);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.tile_property = prop;

        prop = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                        "type", drm_plane_type_enum_list,
                                        ARRAY_SIZE(drm_plane_type_enum_list));
        if (!prop)
                return -ENOMEM;
        dev->mode_config.plane_type_property = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE,
                                         "SHARE_ID", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;

        dev->mode_config.prop_share_id = prop;
        prop = drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE,
                                         "SHARE_FLAGS", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_share_flags = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "SRC_X", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_src_x = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "SRC_Y", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_src_y = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "SRC_W", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_src_w = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "SRC_H", 0, UINT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_src_h = prop;

        prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_X", INT_MIN, INT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_crtc_x = prop;

        prop = drm_property_create_signed_range(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_Y", INT_MIN, INT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_crtc_y = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_W", 0, INT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_crtc_w = prop;

        prop = drm_property_create_range(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_H", 0, INT_MAX);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_crtc_h = prop;

        prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
                        "FB_ID", DRM_MODE_OBJECT_FB);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_fb_id = prop;

        prop = drm_property_create_object(dev, DRM_MODE_PROP_ATOMIC,
                        "CRTC_ID", DRM_MODE_OBJECT_CRTC);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_crtc_id = prop;

        prop = drm_property_create_bool(dev, DRM_MODE_PROP_ATOMIC,
                        "ACTIVE");
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_active = prop;

        prop = drm_property_create(dev,
                        DRM_MODE_PROP_ATOMIC | DRM_MODE_PROP_BLOB,
                        "MODE_ID", 0);
        if (!prop)
                return -ENOMEM;
        dev->mode_config.prop_mode_id = prop;

        return 0;
}

/**
 * drm_mode_create_dvi_i_properties - create DVI-I specific connector properties
 * @dev: DRM device
 *
 * Called by a driver the first time a DVI-I connector is made.
 */
int drm_mode_create_dvi_i_properties(struct drm_device *dev)
{
        struct drm_property *dvi_i_selector;
        struct drm_property *dvi_i_subconnector;

        if (dev->mode_config.dvi_i_select_subconnector_property)
                return 0;

        dvi_i_selector =
                drm_property_create_enum(dev, 0,
                                    "select subconnector",
                                    drm_dvi_i_select_enum_list,
                                    ARRAY_SIZE(drm_dvi_i_select_enum_list));
        dev->mode_config.dvi_i_select_subconnector_property = dvi_i_selector;

        dvi_i_subconnector = drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "subconnector",
                                    drm_dvi_i_subconnector_enum_list,
                                    ARRAY_SIZE(drm_dvi_i_subconnector_enum_list));
        dev->mode_config.dvi_i_subconnector_property = dvi_i_subconnector;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_dvi_i_properties);

/**
 * drm_create_tv_properties - create TV specific connector properties
 * @dev: DRM device
 * @num_modes: number of different TV formats (modes) supported
 * @modes: array of pointers to strings containing name of each format
 *
 * Called by a driver's TV initialization routine, this function creates
 * the TV specific connector properties for a given device.  Caller is
 * responsible for allocating a list of format names and passing them to
 * this routine.
 */
int drm_mode_create_tv_properties(struct drm_device *dev,
                                  unsigned int num_modes,
                                  const char * const modes[])
{
        struct drm_property *tv_selector;
        struct drm_property *tv_subconnector;
        unsigned int i;

        if (dev->mode_config.tv_select_subconnector_property)
                return 0;

        /*
         * Basic connector properties
         */
        tv_selector = drm_property_create_enum(dev, 0,
                                          "select subconnector",
                                          drm_tv_select_enum_list,
                                          ARRAY_SIZE(drm_tv_select_enum_list));
        if (!tv_selector)
                goto nomem;

        dev->mode_config.tv_select_subconnector_property = tv_selector;

        tv_subconnector =
                drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "subconnector",
                                    drm_tv_subconnector_enum_list,
                                    ARRAY_SIZE(drm_tv_subconnector_enum_list));
        if (!tv_subconnector)
                goto nomem;
        dev->mode_config.tv_subconnector_property = tv_subconnector;

        /*
         * Other, TV specific properties: margins & TV modes.
         */
        dev->mode_config.tv_left_margin_property =
                drm_property_create_range(dev, 0, "left margin", 0, 100);
        if (!dev->mode_config.tv_left_margin_property)
                goto nomem;

        dev->mode_config.tv_right_margin_property =
                drm_property_create_range(dev, 0, "right margin", 0, 100);
        if (!dev->mode_config.tv_right_margin_property)
                goto nomem;

        dev->mode_config.tv_top_margin_property =
                drm_property_create_range(dev, 0, "top margin", 0, 100);
        if (!dev->mode_config.tv_top_margin_property)
                goto nomem;

        dev->mode_config.tv_bottom_margin_property =
                drm_property_create_range(dev, 0, "bottom margin", 0, 100);
        if (!dev->mode_config.tv_bottom_margin_property)
                goto nomem;

        dev->mode_config.tv_mode_property =
                drm_property_create(dev, DRM_MODE_PROP_ENUM,
                                    "mode", num_modes);
        if (!dev->mode_config.tv_mode_property)
                goto nomem;

        for (i = 0; i < num_modes; i++)
                drm_property_add_enum(dev->mode_config.tv_mode_property, i,
                                      i, modes[i]);

        dev->mode_config.tv_brightness_property =
                drm_property_create_range(dev, 0, "brightness", 0, 100);
        if (!dev->mode_config.tv_brightness_property)
                goto nomem;

        dev->mode_config.tv_contrast_property =
                drm_property_create_range(dev, 0, "contrast", 0, 100);
        if (!dev->mode_config.tv_contrast_property)
                goto nomem;

        dev->mode_config.tv_flicker_reduction_property =
                drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
        if (!dev->mode_config.tv_flicker_reduction_property)
                goto nomem;

        dev->mode_config.tv_overscan_property =
                drm_property_create_range(dev, 0, "overscan", 0, 100);
        if (!dev->mode_config.tv_overscan_property)
                goto nomem;

        dev->mode_config.tv_saturation_property =
                drm_property_create_range(dev, 0, "saturation", 0, 100);
        if (!dev->mode_config.tv_saturation_property)
                goto nomem;

        dev->mode_config.tv_hue_property =
                drm_property_create_range(dev, 0, "hue", 0, 100);
        if (!dev->mode_config.tv_hue_property)
                goto nomem;

        return 0;
nomem:
        return -ENOMEM;
}
EXPORT_SYMBOL(drm_mode_create_tv_properties);

/**
 * drm_mode_create_scaling_mode_property - create scaling mode property
 * @dev: DRM device
 *
 * Called by a driver the first time it's needed, must be attached to desired
 * connectors.
 */
int drm_mode_create_scaling_mode_property(struct drm_device *dev)
{
        struct drm_property *scaling_mode;

        if (dev->mode_config.scaling_mode_property)
                return 0;

        scaling_mode =
                drm_property_create_enum(dev, 0, "scaling mode",
                                drm_scaling_mode_enum_list,
                                    ARRAY_SIZE(drm_scaling_mode_enum_list));

        dev->mode_config.scaling_mode_property = scaling_mode;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_scaling_mode_property);

/**
 * drm_mode_create_aspect_ratio_property - create aspect ratio property
 * @dev: DRM device
 *
 * Called by a driver the first time it's needed, must be attached to desired
 * connectors.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_create_aspect_ratio_property(struct drm_device *dev)
{
        if (dev->mode_config.aspect_ratio_property)
                return 0;

        dev->mode_config.aspect_ratio_property =
                drm_property_create_enum(dev, 0, "aspect ratio",
                                drm_aspect_ratio_enum_list,
                                ARRAY_SIZE(drm_aspect_ratio_enum_list));

        if (dev->mode_config.aspect_ratio_property == NULL)
                return -ENOMEM;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_aspect_ratio_property);

/**
 * drm_mode_create_dirty_property - create dirty property
 * @dev: DRM device
 *
 * Called by a driver the first time it's needed, must be attached to desired
 * connectors.
 */
int drm_mode_create_dirty_info_property(struct drm_device *dev)
{
        struct drm_property *dirty_info;

        if (dev->mode_config.dirty_info_property)
                return 0;

        dirty_info =
                drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
                                    "dirty",
                                    drm_dirty_info_enum_list,
                                    ARRAY_SIZE(drm_dirty_info_enum_list));
        dev->mode_config.dirty_info_property = dirty_info;

        return 0;
}
EXPORT_SYMBOL(drm_mode_create_dirty_info_property);

/**
 * drm_mode_create_suggested_offset_properties - create suggests offset properties
 * @dev: DRM device
 *
 * Create the the suggested x/y offset property for connectors.
 */
int drm_mode_create_suggested_offset_properties(struct drm_device *dev)
{
        if (dev->mode_config.suggested_x_property && dev->mode_config.suggested_y_property)
                return 0;

        dev->mode_config.suggested_x_property =
                drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested X", 0, 0xffffffff);

        dev->mode_config.suggested_y_property =
                drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE, "suggested Y", 0, 0xffffffff);

        if (dev->mode_config.suggested_x_property == NULL ||
            dev->mode_config.suggested_y_property == NULL)
                return -ENOMEM;
        return 0;
}
EXPORT_SYMBOL(drm_mode_create_suggested_offset_properties);

/**
 * drm_mode_getresources - get graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a set of configuration description structures and return
 * them to the user, including CRTC, connector and framebuffer configuration.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getresources(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_card_res *card_res = data;
        struct list_head *lh;
        struct drm_framebuffer *fb;
        struct drm_connector *connector;
        struct drm_crtc *crtc;
        struct drm_encoder *encoder;
        int ret = 0;
        int connector_count = 0;
        int crtc_count = 0;
        int fb_count = 0;
        int encoder_count = 0;
        int copied = 0;
        uint32_t __user *fb_id;
        uint32_t __user *crtc_id;
        uint32_t __user *connector_id;
        uint32_t __user *encoder_id;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;


        mutex_lock(&file_priv->fbs_lock);
        /*
         * For the non-control nodes we need to limit the list of resources
         * by IDs in the group list for this node
         */
        list_for_each(lh, &file_priv->fbs)
                fb_count++;

        /* handle this in 4 parts */
        /* FBs */
        if (card_res->count_fbs >= fb_count) {
                copied = 0;
                fb_id = (uint32_t __user *)(unsigned long)card_res->fb_id_ptr;
                list_for_each_entry(fb, &file_priv->fbs, filp_head) {
                        if (put_user(fb->base.id, fb_id + copied)) {
                                mutex_unlock(&file_priv->fbs_lock);
                                return -EFAULT;
                        }
                        copied++;
                }
        }
        card_res->count_fbs = fb_count;
        mutex_unlock(&file_priv->fbs_lock);

        /* mode_config.mutex protects the connector list against e.g. DP MST
         * connector hot-adding. CRTC/Plane lists are invariant. */
        mutex_lock(&dev->mode_config.mutex);
        drm_for_each_crtc(crtc, dev)
                crtc_count++;

        drm_for_each_connector(connector, dev)
                connector_count++;

        drm_for_each_encoder(encoder, dev)
                encoder_count++;

        card_res->max_height = dev->mode_config.max_height;
        card_res->min_height = dev->mode_config.min_height;
        card_res->max_width = dev->mode_config.max_width;
        card_res->min_width = dev->mode_config.min_width;

        /* CRTCs */
        if (card_res->count_crtcs >= crtc_count) {
                copied = 0;
                crtc_id = (uint32_t __user *)(unsigned long)card_res->crtc_id_ptr;
                drm_for_each_crtc(crtc, dev) {
                        DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
                        if (put_user(crtc->base.id, crtc_id + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        card_res->count_crtcs = crtc_count;

        /* Encoders */
        if (card_res->count_encoders >= encoder_count) {
                copied = 0;
                encoder_id = (uint32_t __user *)(unsigned long)card_res->encoder_id_ptr;
                drm_for_each_encoder(encoder, dev) {
                        DRM_DEBUG_KMS("[ENCODER:%d:%s]\n", encoder->base.id,
                                        encoder->name);
                        if (put_user(encoder->base.id, encoder_id +
                                     copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        card_res->count_encoders = encoder_count;

        /* Connectors */
        if (card_res->count_connectors >= connector_count) {
                copied = 0;
                connector_id = (uint32_t __user *)(unsigned long)card_res->connector_id_ptr;
                drm_for_each_connector(connector, dev) {
                        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                                connector->base.id,
                                connector->name);
                        if (put_user(connector->base.id,
                                     connector_id + copied)) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        card_res->count_connectors = connector_count;

        DRM_DEBUG_KMS("CRTC[%d] CONNECTORS[%d] ENCODERS[%d]\n", card_res->count_crtcs,
                  card_res->count_connectors, card_res->count_encoders);

out:
        mutex_unlock(&dev->mode_config.mutex);
        return ret;
}

/**
 * drm_mode_getcrtc - get CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a CRTC configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getcrtc(struct drm_device *dev,
                     void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc *crtc_resp = data;
        struct drm_crtc *crtc;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        crtc = drm_crtc_find(dev, crtc_resp->crtc_id);
        if (!crtc)
                return -ENOENT;

        drm_modeset_lock_crtc(crtc, crtc->primary);
        crtc_resp->gamma_size = crtc->gamma_size;
        if (crtc->primary->fb)
                crtc_resp->fb_id = crtc->primary->fb->base.id;
        else
                crtc_resp->fb_id = 0;

        if (crtc->state) {
                crtc_resp->x = crtc->primary->state->src_x >> 16;
                crtc_resp->y = crtc->primary->state->src_y >> 16;
                if (crtc->state->enable) {
                        drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->state->mode);
                        crtc_resp->mode_valid = 1;

                } else {
                        crtc_resp->mode_valid = 0;
                }
        } else {
                crtc_resp->x = crtc->x;
                crtc_resp->y = crtc->y;
                if (crtc->enabled) {
                        drm_mode_convert_to_umode(&crtc_resp->mode, &crtc->mode);
                        crtc_resp->mode_valid = 1;

                } else {
                        crtc_resp->mode_valid = 0;
                }
        }
        drm_modeset_unlock_crtc(crtc);

        return 0;
}

static bool drm_mode_expose_to_userspace(const struct drm_display_mode *mode,
                                         const struct drm_file *file_priv)
{
        /*
         * If user-space hasn't configured the driver to expose the stereo 3D
         * modes, don't expose them.
         */
        if (!file_priv->stereo_allowed && drm_mode_is_stereo(mode))
                return false;

        return true;
}

static struct drm_encoder *drm_connector_get_encoder(struct drm_connector *connector)
{
        /* For atomic drivers only state objects are synchronously updated and
         * protected by modeset locks, so check those first. */
        if (connector->state)
                return connector->state->best_encoder;
        return connector->encoder;
}

/* helper for getconnector and getproperties ioctls */
static int get_properties(struct drm_mode_object *obj, bool atomic,
                uint32_t __user *prop_ptr, uint64_t __user *prop_values,
                uint32_t *arg_count_props)
{
        int props_count;
        int i, ret, copied;

        props_count = obj->properties->count;
        if (!atomic)
                props_count -= obj->properties->atomic_count;

        if ((*arg_count_props >= props_count) && props_count) {
                for (i = 0, copied = 0; copied < props_count; i++) {
                        struct drm_property *prop = obj->properties->properties[i];
                        uint64_t val;

                        if ((prop->flags & DRM_MODE_PROP_ATOMIC) && !atomic)
                                continue;

                        ret = drm_object_property_get_value(obj, prop, &val);
                        if (ret)
                                return ret;

                        if (put_user(prop->base.id, prop_ptr + copied))
                                return -EFAULT;

                        if (put_user(val, prop_values + copied))
                                return -EFAULT;

                        copied++;
                }
        }
        *arg_count_props = props_count;

        return 0;
}

/**
 * drm_mode_getconnector - get connector configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a connector configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getconnector(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_get_connector *out_resp = data;
        struct drm_connector *connector;
        struct drm_encoder *encoder;
        struct drm_display_mode *mode;
        int mode_count = 0;
        int encoders_count = 0;
        int ret = 0;
        int copied = 0;
        int i;
        struct drm_mode_modeinfo u_mode;
        struct drm_mode_modeinfo __user *mode_ptr;
        uint32_t __user *encoder_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        memset(&u_mode, 0, sizeof(struct drm_mode_modeinfo));

        DRM_DEBUG_KMS("[CONNECTOR:%d:?]\n", out_resp->connector_id);

        mutex_lock(&dev->mode_config.mutex);

        connector = drm_connector_find(dev, out_resp->connector_id);
        if (!connector) {
                ret = -ENOENT;
                goto out_unlock;
        }

        for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++)
                if (connector->encoder_ids[i] != 0)
                        encoders_count++;

        if (out_resp->count_modes == 0) {
                connector->funcs->fill_modes(connector,
                                             dev->mode_config.max_width,
                                             dev->mode_config.max_height);
        }

        /* delayed so we get modes regardless of pre-fill_modes state */
        list_for_each_entry(mode, &connector->modes, head)
                if (drm_mode_expose_to_userspace(mode, file_priv))
                        mode_count++;

        out_resp->connector_id = connector->base.id;
        out_resp->connector_type = connector->connector_type;
        out_resp->connector_type_id = connector->connector_type_id;
        out_resp->mm_width = connector->display_info.width_mm;
        out_resp->mm_height = connector->display_info.height_mm;
        out_resp->subpixel = connector->display_info.subpixel_order;
        out_resp->connection = connector->status;

        drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
        encoder = drm_connector_get_encoder(connector);
        if (encoder)
                out_resp->encoder_id = encoder->base.id;
        else
                out_resp->encoder_id = 0;

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if ((out_resp->count_modes >= mode_count) && mode_count) {
                copied = 0;
                mode_ptr = (struct drm_mode_modeinfo __user *)(unsigned long)out_resp->modes_ptr;
                list_for_each_entry(mode, &connector->modes, head) {
                        if (!drm_mode_expose_to_userspace(mode, file_priv))
                                continue;

                        drm_mode_convert_to_umode(&u_mode, mode);
                        if (copy_to_user(mode_ptr + copied,
                                         &u_mode, sizeof(u_mode))) {
                                ret = -EFAULT;
                                goto out;
                        }
                        copied++;
                }
        }
        out_resp->count_modes = mode_count;

        ret = get_properties(&connector->base, file_priv->atomic,
                        (uint32_t __user *)(unsigned long)(out_resp->props_ptr),
                        (uint64_t __user *)(unsigned long)(out_resp->prop_values_ptr),
                        &out_resp->count_props);
        if (ret)
                goto out;

        if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
                copied = 0;
                encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
                for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
                        if (connector->encoder_ids[i] != 0) {
                                if (put_user(connector->encoder_ids[i],
                                             encoder_ptr + copied)) {
                                        ret = -EFAULT;
                                        goto out;
                                }
                                copied++;
                        }
                }
        }
        out_resp->count_encoders = encoders_count;

out:
        drm_modeset_unlock(&dev->mode_config.connection_mutex);

out_unlock:
        mutex_unlock(&dev->mode_config.mutex);

        return ret;
}

static struct drm_crtc *drm_encoder_get_crtc(struct drm_encoder *encoder)
{
        struct drm_connector *connector;
        struct drm_device *dev = encoder->dev;
        bool uses_atomic = false;

        /* For atomic drivers only state objects are synchronously updated and
         * protected by modeset locks, so check those first. */
        drm_for_each_connector(connector, dev) {
                if (!connector->state)
                        continue;

                uses_atomic = true;

                if (connector->state->best_encoder != encoder)
                        continue;

                return connector->state->crtc;
        }

        /* Don't return stale data (e.g. pending async disable). */
        if (uses_atomic)
                return NULL;

        return encoder->crtc;
}

/**
 * drm_mode_getencoder - get encoder configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Construct a encoder configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getencoder(struct drm_device *dev, void *data,
                        struct drm_file *file_priv)
{
        struct drm_mode_get_encoder *enc_resp = data;
        struct drm_encoder *encoder;
        struct drm_crtc *crtc;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        encoder = drm_encoder_find(dev, enc_resp->encoder_id);
        if (!encoder)
                return -ENOENT;

        drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
        crtc = drm_encoder_get_crtc(encoder);
        if (crtc)
                enc_resp->crtc_id = crtc->base.id;
        else
                enc_resp->crtc_id = 0;
        drm_modeset_unlock(&dev->mode_config.connection_mutex);

        enc_resp->encoder_type = encoder->encoder_type;
        enc_resp->encoder_id = encoder->base.id;
        enc_resp->possible_crtcs = encoder->possible_crtcs;
        enc_resp->possible_clones = encoder->possible_clones;

        return 0;
}

/**
 * drm_mode_getplane_res - enumerate all plane resources
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Construct a list of plane ids to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getplane_res(struct drm_device *dev, void *data,
                          struct drm_file *file_priv)
{
        struct drm_mode_get_plane_res *plane_resp = data;
        struct drm_mode_config *config;
        struct drm_plane *plane;
        uint32_t __user *plane_ptr;
        int copied = 0;
        unsigned num_planes;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        config = &dev->mode_config;

        if (file_priv->universal_planes)
                num_planes = config->num_total_plane;
        else
                num_planes = config->num_overlay_plane;
        if (!file_priv->share_planes) {
                if (file_priv->universal_planes)
                        num_planes -= config->num_share_plane;
                else
                        num_planes -= config->num_share_overlay_plane;
        }

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if (num_planes &&
            (plane_resp->count_planes >= num_planes)) {
                plane_ptr = (uint32_t __user *)(unsigned long)plane_resp->plane_id_ptr;

                /* Plane lists are invariant, no locking needed. */
                drm_for_each_plane(plane, dev) {
                        /*
                         * Unless userspace set the 'universal planes'
                         * capability bit, only advertise overlays.
                         */
                        if (plane->type != DRM_PLANE_TYPE_OVERLAY &&
                            !file_priv->universal_planes)
                                continue;
                        if (plane->parent && !file_priv->share_planes)
                                continue;

                        if (put_user(plane->base.id, plane_ptr + copied))
                                return -EFAULT;
                        copied++;
                }
        }
        plane_resp->count_planes = num_planes;

        return 0;
}

/**
 * drm_mode_getplane - get plane configuration
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Construct a plane configuration structure to return to the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getplane(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct drm_mode_get_plane *plane_resp = data;
        struct drm_plane *plane;
        uint32_t __user *format_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        plane = drm_plane_find(dev, plane_resp->plane_id);
        if (!plane)
                return -ENOENT;

        drm_modeset_lock(&plane->mutex, NULL);
        if (plane->crtc)
                plane_resp->crtc_id = plane->crtc->base.id;
        else
                plane_resp->crtc_id = 0;

        if (plane->fb)
                plane_resp->fb_id = plane->fb->base.id;
        else
                plane_resp->fb_id = 0;
        drm_modeset_unlock(&plane->mutex);

        plane_resp->plane_id = plane->base.id;
        plane_resp->possible_crtcs = plane->possible_crtcs;
        plane_resp->gamma_size = 0;

        /*
         * This ioctl is called twice, once to determine how much space is
         * needed, and the 2nd time to fill it.
         */
        if (plane->format_count &&
            (plane_resp->count_format_types >= plane->format_count)) {
                format_ptr = (uint32_t __user *)(unsigned long)plane_resp->format_type_ptr;
                if (copy_to_user(format_ptr,
                                 plane->format_types,
                                 sizeof(uint32_t) * plane->format_count)) {
                        return -EFAULT;
                }
        }
        plane_resp->count_format_types = plane->format_count;

        return 0;
}

/**
 * drm_plane_check_pixel_format - Check if the plane supports the pixel format
 * @plane: plane to check for format support
 * @format: the pixel format
 *
 * Returns:
 * Zero of @plane has @format in its list of supported pixel formats, -EINVAL
 * otherwise.
 */
int drm_plane_check_pixel_format(const struct drm_plane *plane, u32 format)
{
        unsigned int i;

        for (i = 0; i < plane->format_count; i++) {
                if (format == plane->format_types[i])
                        return 0;
        }

        return -EINVAL;
}

static int check_src_coords(uint32_t src_x, uint32_t src_y,
                            uint32_t src_w, uint32_t src_h,
                            const struct drm_framebuffer *fb)
{
        unsigned int fb_width, fb_height;

        fb_width = fb->width << 16;
        fb_height = fb->height << 16;

        /* Make sure source coordinates are inside the fb. */
        if (src_w > fb_width ||
            src_x > fb_width - src_w ||
            src_h > fb_height ||
            src_y > fb_height - src_h) {
                DRM_DEBUG_KMS("Invalid source coordinates "
                              "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
                              src_w >> 16, ((src_w & 0xffff) * 15625) >> 10,
                              src_h >> 16, ((src_h & 0xffff) * 15625) >> 10,
                              src_x >> 16, ((src_x & 0xffff) * 15625) >> 10,
                              src_y >> 16, ((src_y & 0xffff) * 15625) >> 10);
                return -ENOSPC;
        }

        return 0;
}

/*
 * setplane_internal - setplane handler for internal callers
 *
 * Note that we assume an extra reference has already been taken on fb.  If the
 * update fails, this reference will be dropped before return; if it succeeds,
 * the previous framebuffer (if any) will be unreferenced instead.
 *
 * src_{x,y,w,h} are provided in 16.16 fixed point format
 */
static int __setplane_internal(struct drm_plane *plane,
                               struct drm_crtc *crtc,
                               struct drm_framebuffer *fb,
                               int32_t crtc_x, int32_t crtc_y,
                               uint32_t crtc_w, uint32_t crtc_h,
                               /* src_{x,y,w,h} values are 16.16 fixed point */
                               uint32_t src_x, uint32_t src_y,
                               uint32_t src_w, uint32_t src_h)
{
        int ret = 0;

        /* No fb means shut it down */
        if (!fb) {
                plane->old_fb = plane->fb;
                ret = plane->funcs->disable_plane(plane);
                if (!ret) {
                        plane->crtc = NULL;
                        plane->fb = NULL;
                } else {
                        plane->old_fb = NULL;
                }
                goto out;
        }

        /* Check whether this plane is usable on this CRTC */
        if (!(plane->possible_crtcs & drm_crtc_mask(crtc))) {
                DRM_DEBUG_KMS("Invalid crtc for plane\n");
                ret = -EINVAL;
                goto out;
        }

        /* Check whether this plane supports the fb pixel format. */
        ret = drm_plane_check_pixel_format(plane, fb->pixel_format);
        if (ret) {
                DRM_DEBUG_KMS("Invalid pixel format %s\n",
                              drm_get_format_name(fb->pixel_format));
                goto out;
        }

        /* Give drivers some help against integer overflows */
        if (crtc_w > INT_MAX ||
            crtc_x > INT_MAX - (int32_t) crtc_w ||
            crtc_h > INT_MAX ||
            crtc_y > INT_MAX - (int32_t) crtc_h) {
                DRM_DEBUG_KMS("Invalid CRTC coordinates %ux%u+%d+%d\n",
                              crtc_w, crtc_h, crtc_x, crtc_y);
                ret = -ERANGE;
                goto out;
        }

        ret = check_src_coords(src_x, src_y, src_w, src_h, fb);
        if (ret)
                goto out;

        plane->old_fb = plane->fb;
        ret = plane->funcs->update_plane(plane, crtc, fb,
                                         crtc_x, crtc_y, crtc_w, crtc_h,
                                         src_x, src_y, src_w, src_h);
        if (!ret) {
                plane->crtc = crtc;
                plane->fb = fb;
                fb = NULL;
        } else {
                plane->old_fb = NULL;
        }

out:
        if (fb)
                drm_framebuffer_unreference(fb);
        if (plane->old_fb)
                drm_framebuffer_unreference(plane->old_fb);
        plane->old_fb = NULL;

        return ret;
}

static int setplane_internal(struct drm_plane *plane,
                             struct drm_crtc *crtc,
                             struct drm_framebuffer *fb,
                             int32_t crtc_x, int32_t crtc_y,
                             uint32_t crtc_w, uint32_t crtc_h,
                             /* src_{x,y,w,h} values are 16.16 fixed point */
                             uint32_t src_x, uint32_t src_y,
                             uint32_t src_w, uint32_t src_h)
{
        int ret;

        drm_modeset_lock_all(plane->dev);
        ret = __setplane_internal(plane, crtc, fb,
                                  crtc_x, crtc_y, crtc_w, crtc_h,
                                  src_x, src_y, src_w, src_h);
        drm_modeset_unlock_all(plane->dev);

        return ret;
}

/**
 * drm_mode_setplane - configure a plane's configuration
 * @dev: DRM device
 * @data: ioctl data*
 * @file_priv: DRM file info
 *
 * Set plane configuration, including placement, fb, scaling, and other factors.
 * Or pass a NULL fb to disable (planes may be disabled without providing a
 * valid crtc).
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_setplane(struct drm_device *dev, void *data,
                      struct drm_file *file_priv)
{
        struct drm_mode_set_plane *plane_req = data;
        struct drm_plane *plane;
        struct drm_crtc *crtc = NULL;
        struct drm_framebuffer *fb = NULL;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        /*
         * First, find the plane, crtc, and fb objects.  If not available,
         * we don't bother to call the driver.
         */
        plane = drm_plane_find(dev, plane_req->plane_id);
        if (!plane) {
                DRM_DEBUG_KMS("Unknown plane ID %d\n",
                              plane_req->plane_id);
                return -ENOENT;
        }

        if (plane_req->fb_id) {
                fb = drm_framebuffer_lookup(dev, plane_req->fb_id);
                if (!fb) {
                        DRM_DEBUG_KMS("Unknown framebuffer ID %d\n",
                                      plane_req->fb_id);
                        return -ENOENT;
                }

                crtc = drm_crtc_find(dev, plane_req->crtc_id);
                if (!crtc) {
                        DRM_DEBUG_KMS("Unknown crtc ID %d\n",
                                      plane_req->crtc_id);
                        return -ENOENT;
                }
        }

        /*
         * setplane_internal will take care of deref'ing either the old or new
         * framebuffer depending on success.
         */
        return setplane_internal(plane, crtc, fb,
                                 plane_req->crtc_x, plane_req->crtc_y,
                                 plane_req->crtc_w, plane_req->crtc_h,
                                 plane_req->src_x, plane_req->src_y,
                                 plane_req->src_w, plane_req->src_h);
}

/**
 * drm_mode_set_config_internal - helper to call ->set_config
 * @set: modeset config to set
 *
 * This is a little helper to wrap internal calls to the ->set_config driver
 * interface. The only thing it adds is correct refcounting dance.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_set_config_internal(struct drm_mode_set *set)
{
        struct drm_crtc *crtc = set->crtc;
        struct drm_framebuffer *fb;
        struct drm_crtc *tmp;
        int ret;

        /*
         * NOTE: ->set_config can also disable other crtcs (if we steal all
         * connectors from it), hence we need to refcount the fbs across all
         * crtcs. Atomic modeset will have saner semantics ...
         */
        drm_for_each_crtc(tmp, crtc->dev)
                tmp->primary->old_fb = tmp->primary->fb;

        fb = set->fb;

        ret = crtc->funcs->set_config(set);
        if (ret == 0) {
                crtc->primary->crtc = crtc;
                crtc->primary->fb = fb;
        }

        drm_for_each_crtc(tmp, crtc->dev) {
                if (tmp->primary->fb)
                        drm_framebuffer_reference(tmp->primary->fb);
                if (tmp->primary->old_fb)
                        drm_framebuffer_unreference(tmp->primary->old_fb);
                tmp->primary->old_fb = NULL;
        }

        return ret;
}
EXPORT_SYMBOL(drm_mode_set_config_internal);

/**
 * drm_crtc_get_hv_timing - Fetches hdisplay/vdisplay for given mode
 * @mode: mode to query
 * @hdisplay: hdisplay value to fill in
 * @vdisplay: vdisplay value to fill in
 *
 * The vdisplay value will be doubled if the specified mode is a stereo mode of
 * the appropriate layout.
 */
void drm_crtc_get_hv_timing(const struct drm_display_mode *mode,
                            int *hdisplay, int *vdisplay)
{
        struct drm_display_mode adjusted;

        drm_mode_copy(&adjusted, mode);
        drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE_ONLY);
        *hdisplay = adjusted.crtc_hdisplay;
        *vdisplay = adjusted.crtc_vdisplay;
}
EXPORT_SYMBOL(drm_crtc_get_hv_timing);

/**
 * drm_crtc_check_viewport - Checks that a framebuffer is big enough for the
 *     CRTC viewport
 * @crtc: CRTC that framebuffer will be displayed on
 * @x: x panning
 * @y: y panning
 * @mode: mode that framebuffer will be displayed under
 * @fb: framebuffer to check size of
 */
int drm_crtc_check_viewport(const struct drm_crtc *crtc,
                            int x, int y,
                            const struct drm_display_mode *mode,
                            const struct drm_framebuffer *fb)

{
        int hdisplay, vdisplay;

        drm_crtc_get_hv_timing(mode, &hdisplay, &vdisplay);

        if (crtc->state &&
            crtc->primary->state->rotation & (BIT(DRM_ROTATE_90) |
                                              BIT(DRM_ROTATE_270)))
                swap(hdisplay, vdisplay);

        return check_src_coords(x << 16, y << 16,
                                hdisplay << 16, vdisplay << 16, fb);
}
EXPORT_SYMBOL(drm_crtc_check_viewport);

/**
 * drm_mode_setcrtc - set CRTC configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Build a new CRTC configuration based on user request.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_setcrtc(struct drm_device *dev, void *data,
                     struct drm_file *file_priv)
{
        struct drm_mode_config *config = &dev->mode_config;
        struct drm_mode_crtc *crtc_req = data;
        struct drm_crtc *crtc;
        struct drm_connector **connector_set = NULL, *connector;
        struct drm_framebuffer *fb = NULL;
        struct drm_display_mode *mode = NULL;
        struct drm_mode_set set;
        uint32_t __user *set_connectors_ptr;
        int ret;
        int i;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        /*
         * Universal plane src offsets are only 16.16, prevent havoc for
         * drivers using universal plane code internally.
         */
        if (crtc_req->x & 0xffff0000 || crtc_req->y & 0xffff0000)
                return -ERANGE;

        drm_modeset_lock_all(dev);
        crtc = drm_crtc_find(dev, crtc_req->crtc_id);
        if (!crtc) {
                DRM_DEBUG_KMS("Unknown CRTC ID %d\n", crtc_req->crtc_id);
                ret = -ENOENT;
                goto out;
        }
        DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);

        if (crtc_req->mode_valid) {
                /* If we have a mode we need a framebuffer. */
                /* If we pass -1, set the mode with the currently bound fb */
                if (crtc_req->fb_id == -1) {
                        if (!crtc->primary->fb) {
                                DRM_DEBUG_KMS("CRTC doesn't have current FB\n");
                                ret = -EINVAL;
                                goto out;
                        }
                        fb = crtc->primary->fb;
                        /* Make refcounting symmetric with the lookup path. */
                        drm_framebuffer_reference(fb);
                } else {
                        fb = drm_framebuffer_lookup(dev, crtc_req->fb_id);
                        if (!fb) {
                                DRM_DEBUG_KMS("Unknown FB ID%d\n",
                                                crtc_req->fb_id);
                                ret = -ENOENT;
                                goto out;
                        }
                }

                mode = drm_mode_create(dev);
                if (!mode) {
                        ret = -ENOMEM;
                        goto out;
                }

                ret = drm_mode_convert_umode(mode, &crtc_req->mode);
                if (ret) {
                        DRM_DEBUG_KMS("Invalid mode\n");
                        goto out;
                }

                /*
                 * Check whether the primary plane supports the fb pixel format.
                 * Drivers not implementing the universal planes API use a
                 * default formats list provided by the DRM core which doesn't
                 * match real hardware capabilities. Skip the check in that
                 * case.
                 */
                if (!crtc->primary->format_default) {
                        ret = drm_plane_check_pixel_format(crtc->primary,
                                                           fb->pixel_format);
                        if (ret) {
                                DRM_DEBUG_KMS("Invalid pixel format %s\n",
                                        drm_get_format_name(fb->pixel_format));
                                goto out;
                        }
                }

                ret = drm_crtc_check_viewport(crtc, crtc_req->x, crtc_req->y,
                                              mode, fb);
                if (ret)
                        goto out;

        }

        if (crtc_req->count_connectors == 0 && mode) {
                DRM_DEBUG_KMS("Count connectors is 0 but mode set\n");
                ret = -EINVAL;
                goto out;
        }

        if (crtc_req->count_connectors > 0 && (!mode || !fb)) {
                DRM_DEBUG_KMS("Count connectors is %d but no mode or fb set\n",
                          crtc_req->count_connectors);
                ret = -EINVAL;
                goto out;
        }

        if (crtc_req->count_connectors > 0) {
                u32 out_id;

                /* Avoid unbounded kernel memory allocation */
                if (crtc_req->count_connectors > config->num_connector) {
                        ret = -EINVAL;
                        goto out;
                }

                connector_set = kmalloc_array(crtc_req->count_connectors,
                                              sizeof(struct drm_connector *),
                                              GFP_KERNEL);
                if (!connector_set) {
                        ret = -ENOMEM;
                        goto out;
                }

                for (i = 0; i < crtc_req->count_connectors; i++) {
                        set_connectors_ptr = (uint32_t __user *)(unsigned long)crtc_req->set_connectors_ptr;
                        if (get_user(out_id, &set_connectors_ptr[i])) {
                                ret = -EFAULT;
                                goto out;
                        }

                        connector = drm_connector_find(dev, out_id);
                        if (!connector) {
                                DRM_DEBUG_KMS("Connector id %d unknown\n",
                                                out_id);
                                ret = -ENOENT;
                                goto out;
                        }
                        DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
                                        connector->base.id,
                                        connector->name);

                        connector_set[i] = connector;
                }
        }

        set.crtc = crtc;
        set.x = crtc_req->x;
        set.y = crtc_req->y;
        set.mode = mode;
        set.connectors = connector_set;
        set.num_connectors = crtc_req->count_connectors;
        set.fb = fb;
        ret = drm_mode_set_config_internal(&set);

out:
        if (fb)
                drm_framebuffer_unreference(fb);

        kfree(connector_set);
        drm_mode_destroy(dev, mode);
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_cursor_universal - translate legacy cursor ioctl call into a
 *     universal plane handler call
 * @crtc: crtc to update cursor for
 * @req: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Legacy cursor ioctl's work directly with driver buffer handles.  To
 * translate legacy ioctl calls into universal plane handler calls, we need to
 * wrap the native buffer handle in a drm_framebuffer.
 *
 * Note that we assume any handle passed to the legacy ioctls was a 32-bit ARGB
 * buffer with a pitch of 4*width; the universal plane interface should be used
 * directly in cases where the hardware can support other buffer settings and
 * userspace wants to make use of these capabilities.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
static int drm_mode_cursor_universal(struct drm_crtc *crtc,
                                     struct drm_mode_cursor2 *req,
                                     struct drm_file *file_priv)
{
        struct drm_device *dev = crtc->dev;
        struct drm_framebuffer *fb = NULL;
        struct drm_mode_fb_cmd2 fbreq = {
                .width = req->width,
                .height = req->height,
                .pixel_format = DRM_FORMAT_ARGB8888,
                .pitches = { req->width * 4 },
                .handles = { req->handle },
        };
        int32_t crtc_x, crtc_y;
        uint32_t crtc_w = 0, crtc_h = 0;
        uint32_t src_w = 0, src_h = 0;
        int ret = 0;

        BUG_ON(!crtc->cursor);
        WARN_ON(crtc->cursor->crtc != crtc && crtc->cursor->crtc != NULL);

        /*
         * Obtain fb we'll be using (either new or existing) and take an extra
         * reference to it if fb != null.  setplane will take care of dropping
         * the reference if the plane update fails.
         */
        if (req->flags & DRM_MODE_CURSOR_BO) {
                if (req->handle) {
                        fb = internal_framebuffer_create(dev, &fbreq, file_priv);
                        if (IS_ERR(fb)) {
                                DRM_DEBUG_KMS("failed to wrap cursor buffer in drm framebuffer\n");
                                return PTR_ERR(fb);
                        }
                } else {
                        fb = NULL;
                }
        } else {
                fb = crtc->cursor->fb;
                if (fb)
                        drm_framebuffer_reference(fb);
        }

        if (req->flags & DRM_MODE_CURSOR_MOVE) {
                crtc_x = req->x;
                crtc_y = req->y;
        } else {
                crtc_x = crtc->cursor_x;
                crtc_y = crtc->cursor_y;
        }

        if (fb) {
                crtc_w = fb->width;
                crtc_h = fb->height;
                src_w = fb->width << 16;
                src_h = fb->height << 16;
        }

        /*
         * setplane_internal will take care of deref'ing either the old or new
         * framebuffer depending on success.
         */
        ret = __setplane_internal(crtc->cursor, crtc, fb,
                                crtc_x, crtc_y, crtc_w, crtc_h,
                                0, 0, src_w, src_h);

        /* Update successful; save new cursor position, if necessary */
        if (ret == 0 && req->flags & DRM_MODE_CURSOR_MOVE) {
                crtc->cursor_x = req->x;
                crtc->cursor_y = req->y;
        }

        return ret;
}

static int drm_mode_cursor_common(struct drm_device *dev,
                                  struct drm_mode_cursor2 *req,
                                  struct drm_file *file_priv)
{
        struct drm_crtc *crtc;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        if (!req->flags || (~DRM_MODE_CURSOR_FLAGS & req->flags))
                return -EINVAL;

        crtc = drm_crtc_find(dev, req->crtc_id);
        if (!crtc) {
                DRM_DEBUG_KMS("Unknown CRTC ID %d\n", req->crtc_id);
                return -ENOENT;
        }

        /*
         * If this crtc has a universal cursor plane, call that plane's update
         * handler rather than using legacy cursor handlers.
         */
        drm_modeset_lock_crtc(crtc, crtc->cursor);
        if (crtc->cursor) {
                ret = drm_mode_cursor_universal(crtc, req, file_priv);
                goto out;
        }

        if (req->flags & DRM_MODE_CURSOR_BO) {
                if (!crtc->funcs->cursor_set && !crtc->funcs->cursor_set2) {
                        ret = -ENXIO;
                        goto out;
                }
                /* Turns off the cursor if handle is 0 */
                if (crtc->funcs->cursor_set2)
                        ret = crtc->funcs->cursor_set2(crtc, file_priv, req->handle,
                                                      req->width, req->height, req->hot_x, req->hot_y);
                else
                        ret = crtc->funcs->cursor_set(crtc, file_priv, req->handle,
                                                      req->width, req->height);
        }

        if (req->flags & DRM_MODE_CURSOR_MOVE) {
                if (crtc->funcs->cursor_move) {
                        ret = crtc->funcs->cursor_move(crtc, req->x, req->y);
                } else {
                        ret = -EFAULT;
                        goto out;
                }
        }
out:
        drm_modeset_unlock_crtc(crtc);

        return ret;

}


/**
 * drm_mode_cursor_ioctl - set CRTC's cursor configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Set the cursor configuration based on user request.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_cursor_ioctl(struct drm_device *dev,
                          void *data, struct drm_file *file_priv)
{
        struct drm_mode_cursor *req = data;
        struct drm_mode_cursor2 new_req;

        memcpy(&new_req, req, sizeof(struct drm_mode_cursor));
        new_req.hot_x = new_req.hot_y = 0;

        return drm_mode_cursor_common(dev, &new_req, file_priv);
}

/**
 * drm_mode_cursor2_ioctl - set CRTC's cursor configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Set the cursor configuration based on user request. This implements the 2nd
 * version of the cursor ioctl, which allows userspace to additionally specify
 * the hotspot of the pointer.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_cursor2_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_mode_cursor2 *req = data;

        return drm_mode_cursor_common(dev, req, file_priv);
}

/**
 * drm_mode_legacy_fb_format - compute drm fourcc code from legacy description
 * @bpp: bits per pixels
 * @depth: bit depth per pixel
 *
 * Computes a drm fourcc pixel format code for the given @bpp/@depth values.
 * Useful in fbdev emulation code, since that deals in those values.
 */
uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
{
        uint32_t fmt;

        switch (bpp) {
        case 8:
                fmt = DRM_FORMAT_C8;
                break;
        case 16:
                if (depth == 15)
                        fmt = DRM_FORMAT_XRGB1555;
                else
                        fmt = DRM_FORMAT_RGB565;
                break;
        case 24:
                fmt = DRM_FORMAT_RGB888;
                break;
        case 32:
                if (depth == 24)
                        fmt = DRM_FORMAT_XRGB8888;
                else if (depth == 30)
                        fmt = DRM_FORMAT_XRGB2101010;
                else
                        fmt = DRM_FORMAT_ARGB8888;
                break;
        default:
                DRM_ERROR("bad bpp, assuming x8r8g8b8 pixel format\n");
                fmt = DRM_FORMAT_XRGB8888;
                break;
        }

        return fmt;
}
EXPORT_SYMBOL(drm_mode_legacy_fb_format);

/**
 * drm_mode_addfb - add an FB to the graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Add a new FB to the specified CRTC, given a user request. This is the
 * original addfb ioctl which only supported RGB formats.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_addfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd *or = data;
        struct drm_mode_fb_cmd2 r = {};
        int ret;

        /* convert to new format and call new ioctl */
        r.fb_id = or->fb_id;
        r.width = or->width;
        r.height = or->height;
        r.pitches[0] = or->pitch;
        r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
        r.handles[0] = or->handle;

        ret = drm_mode_addfb2(dev, &r, file_priv);
        if (ret)
                return ret;

        or->fb_id = r.fb_id;

        return 0;
}

static int format_check(const struct drm_mode_fb_cmd2 *r)
{
        uint32_t format = r->pixel_format & ~DRM_FORMAT_BIG_ENDIAN;

        switch (format) {
        case DRM_FORMAT_C8:
        case DRM_FORMAT_RGB332:
        case DRM_FORMAT_BGR233:
        case DRM_FORMAT_XRGB4444:
        case DRM_FORMAT_XBGR4444:
        case DRM_FORMAT_RGBX4444:
        case DRM_FORMAT_BGRX4444:
        case DRM_FORMAT_ARGB4444:
        case DRM_FORMAT_ABGR4444:
        case DRM_FORMAT_RGBA4444:
        case DRM_FORMAT_BGRA4444:
        case DRM_FORMAT_XRGB1555:
        case DRM_FORMAT_XBGR1555:
        case DRM_FORMAT_RGBX5551:
        case DRM_FORMAT_BGRX5551:
        case DRM_FORMAT_ARGB1555:
        case DRM_FORMAT_ABGR1555:
        case DRM_FORMAT_RGBA5551:
        case DRM_FORMAT_BGRA5551:
        case DRM_FORMAT_RGB565:
        case DRM_FORMAT_BGR565:
        case DRM_FORMAT_RGB888:
        case DRM_FORMAT_BGR888:
        case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_XBGR8888:
        case DRM_FORMAT_RGBX8888:
        case DRM_FORMAT_BGRX8888:
        case DRM_FORMAT_ARGB8888:
        case DRM_FORMAT_ABGR8888:
        case DRM_FORMAT_RGBA8888:
        case DRM_FORMAT_BGRA8888:
        case DRM_FORMAT_XRGB2101010:
        case DRM_FORMAT_XBGR2101010:
        case DRM_FORMAT_RGBX1010102:
        case DRM_FORMAT_BGRX1010102:
        case DRM_FORMAT_ARGB2101010:
        case DRM_FORMAT_ABGR2101010:
        case DRM_FORMAT_RGBA1010102:
        case DRM_FORMAT_BGRA1010102:
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
        case DRM_FORMAT_AYUV:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
        case DRM_FORMAT_NV12_10:
        case DRM_FORMAT_NV21_10:
        case DRM_FORMAT_NV16_10:
        case DRM_FORMAT_NV61_10:
        case DRM_FORMAT_NV24_10:
        case DRM_FORMAT_NV42_10:
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 0;
        default:
                DRM_DEBUG_KMS("invalid pixel format %s\n",
                              drm_get_format_name(r->pixel_format));
                return -EINVAL;
        }
}

static int framebuffer_check(const struct drm_mode_fb_cmd2 *r)
{
        int ret, hsub, vsub, num_planes, i;

        ret = format_check(r);
        if (ret) {
                DRM_DEBUG_KMS("bad framebuffer format %s\n",
                              drm_get_format_name(r->pixel_format));
                return ret;
        }

        hsub = drm_format_horz_chroma_subsampling(r->pixel_format);
        vsub = drm_format_vert_chroma_subsampling(r->pixel_format);
        num_planes = drm_format_num_planes(r->pixel_format);

        if (r->width == 0 || r->width % hsub) {
                DRM_DEBUG_KMS("bad framebuffer width %u\n", r->width);
                return -EINVAL;
        }

        if (r->height == 0 || r->height % vsub) {
                DRM_DEBUG_KMS("bad framebuffer height %u\n", r->height);
                return -EINVAL;
        }

        for (i = 0; i < num_planes; i++) {
                unsigned int width = r->width / (i != 0 ? hsub : 1);
                unsigned int height = r->height / (i != 0 ? vsub : 1);
                unsigned int bpp = drm_format_plane_bpp(r->pixel_format, i);

                if (!r->handles[i]) {
                        DRM_DEBUG_KMS("no buffer object handle for plane %d\n", i);
                        return -EINVAL;
                }

                if ((uint64_t) width * bpp / 8 > UINT_MAX)
                        return -ERANGE;

                if ((uint64_t) height * r->pitches[i] + r->offsets[i] > UINT_MAX)
                        return -ERANGE;

                if (r->pitches[i] < roundup(width * bpp, 8) / 8) {
                        DRM_DEBUG_KMS("bad pitch %u for plane %d\n", r->pitches[i], i);
                        return -EINVAL;
                }

                if (r->modifier[i] && !(r->flags & DRM_MODE_FB_MODIFIERS)) {
                        DRM_DEBUG_KMS("bad fb modifier %llu for plane %d\n",
                                      r->modifier[i], i);
                        return -EINVAL;
                }

                /* modifier specific checks: */
                switch (r->modifier[i]) {
                case DRM_FORMAT_MOD_SAMSUNG_64_32_TILE:
                        /* NOTE: the pitch restriction may be lifted later if it turns
                         * out that no hw has this restriction:
                         */
                        if (r->pixel_format != DRM_FORMAT_NV12 ||
                                        width % 128 || height % 32 ||
                                        r->pitches[i] % 128) {
                                DRM_DEBUG_KMS("bad modifier data for plane %d\n", i);
                                return -EINVAL;
                        }
                        break;

                default:
                        break;
                }
        }

        for (i = num_planes; i < 4; i++) {
                if (r->modifier[i]) {
                        DRM_DEBUG_KMS("non-zero modifier for unused plane %d\n", i);
                        return -EINVAL;
                }

                /* Pre-FB_MODIFIERS userspace didn't clear the structs properly. */
                if (!(r->flags & DRM_MODE_FB_MODIFIERS))
                        continue;

                if (r->handles[i]) {
                        DRM_DEBUG_KMS("buffer object handle for unused plane %d\n", i);
                        return -EINVAL;
                }

                if (r->pitches[i]) {
                        DRM_DEBUG_KMS("non-zero pitch for unused plane %d\n", i);
                        return -EINVAL;
                }

                if (r->offsets[i]) {
                        DRM_DEBUG_KMS("non-zero offset for unused plane %d\n", i);
                        return -EINVAL;
                }
        }

        return 0;
}

static struct drm_framebuffer *
internal_framebuffer_create(struct drm_device *dev,
                            struct drm_mode_fb_cmd2 *r,
                            struct drm_file *file_priv)
{
        struct drm_mode_config *config = &dev->mode_config;
        struct drm_framebuffer *fb;
        int ret;

        if (r->flags & ~(DRM_MODE_FB_INTERLACED | DRM_MODE_FB_MODIFIERS)) {
                DRM_DEBUG_KMS("bad framebuffer flags 0x%08x\n", r->flags);
                return ERR_PTR(-EINVAL);
        }

        if ((config->min_width > r->width) || (r->width > config->max_width)) {
                DRM_DEBUG_KMS("bad framebuffer width %d, should be >= %d && <= %d\n",
                          r->width, config->min_width, config->max_width);
                return ERR_PTR(-EINVAL);
        }
        if ((config->min_height > r->height) || (r->height > config->max_height)) {
                DRM_DEBUG_KMS("bad framebuffer height %d, should be >= %d && <= %d\n",
                          r->height, config->min_height, config->max_height);
                return ERR_PTR(-EINVAL);
        }

        if (r->flags & DRM_MODE_FB_MODIFIERS &&
            !dev->mode_config.allow_fb_modifiers) {
                DRM_DEBUG_KMS("driver does not support fb modifiers\n");
                return ERR_PTR(-EINVAL);
        }

        ret = framebuffer_check(r);
        if (ret)
                return ERR_PTR(ret);

        fb = dev->mode_config.funcs->fb_create(dev, file_priv, r);
        if (IS_ERR(fb)) {
                DRM_DEBUG_KMS("could not create framebuffer\n");
                return fb;
        }

        return fb;
}

/**
 * drm_mode_addfb2 - add an FB to the graphics configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Add a new FB to the specified CRTC, given a user request with format. This is
 * the 2nd version of the addfb ioctl, which supports multi-planar framebuffers
 * and uses fourcc codes as pixel format specifiers.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_addfb2(struct drm_device *dev,
                    void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd2 *r = data;
        struct drm_framebuffer *fb;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        fb = internal_framebuffer_create(dev, r, file_priv);
        if (IS_ERR(fb))
                return PTR_ERR(fb);

        /* Transfer ownership to the filp for reaping on close */

        DRM_DEBUG_KMS("[FB:%d]\n", fb->base.id);
        mutex_lock(&file_priv->fbs_lock);
        r->fb_id = fb->base.id;
        list_add(&fb->filp_head, &file_priv->fbs);
        mutex_unlock(&file_priv->fbs_lock);

        return 0;
}

struct drm_mode_rmfb_work {
        struct work_struct work;
        struct list_head fbs;
};

static void drm_mode_rmfb_work_fn(struct work_struct *w)
{
        struct drm_mode_rmfb_work *arg = container_of(w, typeof(*arg), work);

        while (!list_empty(&arg->fbs)) {
                struct drm_framebuffer *fb =
                        list_first_entry(&arg->fbs, typeof(*fb), filp_head);

                list_del_init(&fb->filp_head);
                drm_framebuffer_remove(fb);
        }
}

/**
 * drm_mode_rmfb - remove an FB from the configuration
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Remove the FB specified by the user.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_rmfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_framebuffer *fb = NULL;
        struct drm_framebuffer *fbl = NULL;
        uint32_t *id = data;
        int found = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        mutex_lock(&file_priv->fbs_lock);
        mutex_lock(&dev->mode_config.fb_lock);
        fb = __drm_framebuffer_lookup(dev, *id);
        if (!fb)
                goto fail_lookup;

        list_for_each_entry(fbl, &file_priv->fbs, filp_head)
                if (fb == fbl)
                        found = 1;
        if (!found)
                goto fail_lookup;

        list_del_init(&fb->filp_head);
        mutex_unlock(&dev->mode_config.fb_lock);
        mutex_unlock(&file_priv->fbs_lock);

        /*
         * we now own the reference that was stored in the fbs list
         *
         * drm_framebuffer_remove may fail with -EINTR on pending signals,
         * so run this in a separate stack as there's no way to correctly
         * handle this after the fb is already removed from the lookup table.
         */
        if (atomic_read(&fb->refcount.refcount) > 1) {
                struct drm_mode_rmfb_work arg;

                INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
                INIT_LIST_HEAD(&arg.fbs);
                list_add_tail(&fb->filp_head, &arg.fbs);

                schedule_work(&arg.work);
                flush_work(&arg.work);
                destroy_work_on_stack(&arg.work);
        } else
                drm_framebuffer_unreference(fb);

        return 0;

fail_lookup:
        mutex_unlock(&dev->mode_config.fb_lock);
        mutex_unlock(&file_priv->fbs_lock);

        return -ENOENT;
}

/**
 * drm_mode_getfb - get FB info
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Lookup the FB given its ID and return info about it.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getfb(struct drm_device *dev,
                   void *data, struct drm_file *file_priv)
{
        struct drm_mode_fb_cmd *r = data;
        struct drm_framebuffer *fb;
        int ret;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        fb = drm_framebuffer_lookup(dev, r->fb_id);
        if (!fb)
                return -ENOENT;

        r->height = fb->height;
        r->width = fb->width;
        r->depth = fb->depth;
        r->bpp = fb->bits_per_pixel;
        r->pitch = fb->pitches[0];
        if (fb->funcs->create_handle) {
                if (file_priv->is_master || capable(CAP_SYS_ADMIN) ||
                    drm_is_control_client(file_priv)) {
                        ret = fb->funcs->create_handle(fb, file_priv,
                                                       &r->handle);
                } else {
                        /* GET_FB() is an unprivileged ioctl so we must not
                         * return a buffer-handle to non-master processes! For
                         * backwards-compatibility reasons, we cannot make
                         * GET_FB() privileged, so just return an invalid handle
                         * for non-masters. */
                        r->handle = 0;
                        ret = 0;
                }
        } else {
                ret = -ENODEV;
        }

        drm_framebuffer_unreference(fb);

        return ret;
}

/**
 * drm_mode_dirtyfb_ioctl - flush frontbuffer rendering on an FB
 * @dev: drm device for the ioctl
 * @data: data pointer for the ioctl
 * @file_priv: drm file for the ioctl call
 *
 * Lookup the FB and flush out the damaged area supplied by userspace as a clip
 * rectangle list. Generic userspace which does frontbuffer rendering must call
 * this ioctl to flush out the changes on manual-update display outputs, e.g.
 * usb display-link, mipi manual update panels or edp panel self refresh modes.
 *
 * Modesetting drivers which always update the frontbuffer do not need to
 * implement the corresponding ->dirty framebuffer callback.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_dirtyfb_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_clip_rect __user *clips_ptr;
        struct drm_clip_rect *clips = NULL;
        struct drm_mode_fb_dirty_cmd *r = data;
        struct drm_framebuffer *fb;
        unsigned flags;
        int num_clips;
        int ret;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        fb = drm_framebuffer_lookup(dev, r->fb_id);
        if (!fb)
                return -ENOENT;

        num_clips = r->num_clips;
        clips_ptr = (struct drm_clip_rect __user *)(unsigned long)r->clips_ptr;

        if (!num_clips != !clips_ptr) {
                ret = -EINVAL;
                goto out_err1;
        }

        flags = DRM_MODE_FB_DIRTY_FLAGS & r->flags;

        /* If userspace annotates copy, clips must come in pairs */
        if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY && (num_clips % 2)) {
                ret = -EINVAL;
                goto out_err1;
        }

        if (num_clips && clips_ptr) {
                if (num_clips < 0 || num_clips > DRM_MODE_FB_DIRTY_MAX_CLIPS) {
                        ret = -EINVAL;
                        goto out_err1;
                }
                clips = kcalloc(num_clips, sizeof(*clips), GFP_KERNEL);
                if (!clips) {
                        ret = -ENOMEM;
                        goto out_err1;
                }

                ret = copy_from_user(clips, clips_ptr,
                                     num_clips * sizeof(*clips));
                if (ret) {
                        ret = -EFAULT;
                        goto out_err2;
                }
        }

        if (fb->funcs->dirty) {
                ret = fb->funcs->dirty(fb, file_priv, flags, r->color,
                                       clips, num_clips);
        } else {
                ret = -ENOSYS;
        }

out_err2:
        kfree(clips);
out_err1:
        drm_framebuffer_unreference(fb);

        return ret;
}

/**
 * drm_fb_release - remove and free the FBs on this file
 * @priv: drm file for the ioctl
 *
 * Destroy all the FBs associated with @filp.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
void drm_fb_release(struct drm_file *priv)
{
        struct drm_framebuffer *fb, *tfb;
        struct drm_mode_rmfb_work arg;

        INIT_LIST_HEAD(&arg.fbs);

        /*
         * When the file gets released that means no one else can access the fb
         * list any more, so no need to grab fpriv->fbs_lock. And we need to
         * avoid upsetting lockdep since the universal cursor code adds a
         * framebuffer while holding mutex locks.
         *
         * Note that a real deadlock between fpriv->fbs_lock and the modeset
         * locks is impossible here since no one else but this function can get
         * at it any more.
         */
        list_for_each_entry_safe(fb, tfb, &priv->fbs, filp_head) {
                if (atomic_read(&fb->refcount.refcount) > 1) {
                        list_move_tail(&fb->filp_head, &arg.fbs);
                } else {
                        list_del_init(&fb->filp_head);

                        /* This drops the fpriv->fbs reference. */
                        drm_framebuffer_unreference(fb);
                }
        }

        if (!list_empty(&arg.fbs)) {
                INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);

                schedule_work(&arg.work);
                flush_work(&arg.work);
                destroy_work_on_stack(&arg.work);
        }
}

/**
 * drm_property_create - create a new property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @num_values: number of pre-defined values
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Note that the DRM core keeps a per-device list of properties and that, if
 * drm_mode_config_cleanup() is called, it will destroy all properties created
 * by the driver.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create(struct drm_device *dev, int flags,
                                         const char *name, int num_values)
{
        struct drm_property *property = NULL;
        int ret;

        property = kzalloc(sizeof(struct drm_property), GFP_KERNEL);
        if (!property)
                return NULL;

        property->dev = dev;

        if (num_values) {
                property->values = kcalloc(num_values, sizeof(uint64_t),
                                           GFP_KERNEL);
                if (!property->values)
                        goto fail;
        }

        ret = drm_mode_object_get(dev, &property->base, DRM_MODE_OBJECT_PROPERTY);
        if (ret)
                goto fail;

        property->flags = flags;
        property->num_values = num_values;
        INIT_LIST_HEAD(&property->enum_list);

        if (name) {
                strncpy(property->name, name, DRM_PROP_NAME_LEN);
                property->name[DRM_PROP_NAME_LEN-1] = '\0';
        }

        list_add_tail(&property->head, &dev->mode_config.property_list);

        WARN_ON(!drm_property_type_valid(property));

        return property;
fail:
        kfree(property->values);
        kfree(property);
        return NULL;
}
EXPORT_SYMBOL(drm_property_create);

/**
 * drm_property_create_enum - create a new enumeration property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @props: enumeration lists with property values
 * @num_values: number of pre-defined values
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is only allowed to set one of the predefined values for enumeration
 * properties.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_enum(struct drm_device *dev, int flags,
                                         const char *name,
                                         const struct drm_prop_enum_list *props,
                                         int num_values)
{
        struct drm_property *property;
        int i, ret;

        flags |= DRM_MODE_PROP_ENUM;

        property = drm_property_create(dev, flags, name, num_values);
        if (!property)
                return NULL;

        for (i = 0; i < num_values; i++) {
                ret = drm_property_add_enum(property, i,
                                      props[i].type,
                                      props[i].name);
                if (ret) {
                        drm_property_destroy(dev, property);
                        return NULL;
                }
        }

        return property;
}
EXPORT_SYMBOL(drm_property_create_enum);

/**
 * drm_property_create_bitmask - create a new bitmask property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @props: enumeration lists with property bitflags
 * @num_props: size of the @props array
 * @supported_bits: bitmask of all supported enumeration values
 *
 * This creates a new bitmask drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Compared to plain enumeration properties userspace is allowed to set any
 * or'ed together combination of the predefined property bitflag values
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_bitmask(struct drm_device *dev,
                                         int flags, const char *name,
                                         const struct drm_prop_enum_list *props,
                                         int num_props,
                                         uint64_t supported_bits)
{
        struct drm_property *property;
        int i, ret, index = 0;
        int num_values = hweight64(supported_bits);

        flags |= DRM_MODE_PROP_BITMASK;

        property = drm_property_create(dev, flags, name, num_values);
        if (!property)
                return NULL;
        for (i = 0; i < num_props; i++) {
                if (!(supported_bits & (1ULL << props[i].type)))
                        continue;

                if (WARN_ON(index >= num_values)) {
                        drm_property_destroy(dev, property);
                        return NULL;
                }

                ret = drm_property_add_enum(property, index++,
                                      props[i].type,
                                      props[i].name);
                if (ret) {
                        drm_property_destroy(dev, property);
                        return NULL;
                }
        }

        return property;
}
EXPORT_SYMBOL(drm_property_create_bitmask);

static struct drm_property *property_create_range(struct drm_device *dev,
                                         int flags, const char *name,
                                         uint64_t min, uint64_t max)
{
        struct drm_property *property;

        property = drm_property_create(dev, flags, name, 2);
        if (!property)
                return NULL;

        property->values[0] = min;
        property->values[1] = max;

        return property;
}

/**
 * drm_property_create_range - create a new unsigned ranged property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @min: minimum value of the property
 * @max: maximum value of the property
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is allowed to set any unsigned integer value in the (min, max)
 * range inclusive.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_range(struct drm_device *dev, int flags,
                                         const char *name,
                                         uint64_t min, uint64_t max)
{
        return property_create_range(dev, DRM_MODE_PROP_RANGE | flags,
                        name, min, max);
}
EXPORT_SYMBOL(drm_property_create_range);

/**
 * drm_property_create_signed_range - create a new signed ranged property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @min: minimum value of the property
 * @max: maximum value of the property
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is allowed to set any signed integer value in the (min, max)
 * range inclusive.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_signed_range(struct drm_device *dev,
                                         int flags, const char *name,
                                         int64_t min, int64_t max)
{
        return property_create_range(dev, DRM_MODE_PROP_SIGNED_RANGE | flags,
                        name, I642U64(min), I642U64(max));
}
EXPORT_SYMBOL(drm_property_create_signed_range);

/**
 * drm_property_create_object - create a new object property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 * @type: object type from DRM_MODE_OBJECT_* defines
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * Userspace is only allowed to set this to any property value of the given
 * @type. Only useful for atomic properties, which is enforced.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_object(struct drm_device *dev,
                                         int flags, const char *name, uint32_t type)
{
        struct drm_property *property;

        flags |= DRM_MODE_PROP_OBJECT;

        if (WARN_ON(!(flags & DRM_MODE_PROP_ATOMIC)))
                return NULL;

        property = drm_property_create(dev, flags, name, 1);
        if (!property)
                return NULL;

        property->values[0] = type;

        return property;
}
EXPORT_SYMBOL(drm_property_create_object);

/**
 * drm_property_create_bool - create a new boolean property type
 * @dev: drm device
 * @flags: flags specifying the property type
 * @name: name of the property
 *
 * This creates a new generic drm property which can then be attached to a drm
 * object with drm_object_attach_property. The returned property object must be
 * freed with drm_property_destroy.
 *
 * This is implemented as a ranged property with only {0, 1} as valid values.
 *
 * Returns:
 * A pointer to the newly created property on success, NULL on failure.
 */
struct drm_property *drm_property_create_bool(struct drm_device *dev, int flags,
                                         const char *name)
{
        return drm_property_create_range(dev, flags, name, 0, 1);
}
EXPORT_SYMBOL(drm_property_create_bool);

/**
 * drm_property_add_enum - add a possible value to an enumeration property
 * @property: enumeration property to change
 * @index: index of the new enumeration
 * @value: value of the new enumeration
 * @name: symbolic name of the new enumeration
 *
 * This functions adds enumerations to a property.
 *
 * It's use is deprecated, drivers should use one of the more specific helpers
 * to directly create the property with all enumerations already attached.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_property_add_enum(struct drm_property *property, int index,
                          uint64_t value, const char *name)
{
        struct drm_property_enum *prop_enum;

        if (!(drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
                        drm_property_type_is(property, DRM_MODE_PROP_BITMASK)))
                return -EINVAL;

        /*
         * Bitmask enum properties have the additional constraint of values
         * from 0 to 63
         */
        if (drm_property_type_is(property, DRM_MODE_PROP_BITMASK) &&
                        (value > 63))
                return -EINVAL;

        if (!list_empty(&property->enum_list)) {
                list_for_each_entry(prop_enum, &property->enum_list, head) {
                        if (prop_enum->value == value) {
                                strncpy(prop_enum->name, name, DRM_PROP_NAME_LEN);
                                prop_enum->name[DRM_PROP_NAME_LEN-1] = '\0';
                                return 0;
                        }
                }
        }

        prop_enum = kzalloc(sizeof(struct drm_property_enum), GFP_KERNEL);
        if (!prop_enum)
                return -ENOMEM;

        strncpy(prop_enum->name, name, DRM_PROP_NAME_LEN);
        prop_enum->name[DRM_PROP_NAME_LEN-1] = '\0';
        prop_enum->value = value;

        property->values[index] = value;
        list_add_tail(&prop_enum->head, &property->enum_list);
        return 0;
}
EXPORT_SYMBOL(drm_property_add_enum);

/**
 * drm_property_destroy - destroy a drm property
 * @dev: drm device
 * @property: property to destry
 *
 * This function frees a property including any attached resources like
 * enumeration values.
 */
void drm_property_destroy(struct drm_device *dev, struct drm_property *property)
{
        struct drm_property_enum *prop_enum, *pt;

        list_for_each_entry_safe(prop_enum, pt, &property->enum_list, head) {
                list_del(&prop_enum->head);
                kfree(prop_enum);
        }

        if (property->num_values)
                kfree(property->values);
        drm_mode_object_put(dev, &property->base);
        list_del(&property->head);
        kfree(property);
}
EXPORT_SYMBOL(drm_property_destroy);

/**
 * drm_object_attach_property - attach a property to a modeset object
 * @obj: drm modeset object
 * @property: property to attach
 * @init_val: initial value of the property
 *
 * This attaches the given property to the modeset object with the given initial
 * value. Currently this function cannot fail since the properties are stored in
 * a statically sized array.
 */
void drm_object_attach_property(struct drm_mode_object *obj,
                                struct drm_property *property,
                                uint64_t init_val)
{
        int count = obj->properties->count;

        if (count == DRM_OBJECT_MAX_PROPERTY) {
                WARN(1, "Failed to attach object property (type: 0x%x). Please "
                        "increase DRM_OBJECT_MAX_PROPERTY by 1 for each time "
                        "you see this message on the same object type.\n",
                        obj->type);
                return;
        }

        obj->properties->properties[count] = property;
        obj->properties->values[count] = init_val;
        obj->properties->count++;
        if (property->flags & DRM_MODE_PROP_ATOMIC)
                obj->properties->atomic_count++;
}
EXPORT_SYMBOL(drm_object_attach_property);

/**
 * drm_object_property_set_value - set the value of a property
 * @obj: drm mode object to set property value for
 * @property: property to set
 * @val: value the property should be set to
 *
 * This functions sets a given property on a given object. This function only
 * changes the software state of the property, it does not call into the
 * driver's ->set_property callback.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_object_property_set_value(struct drm_mode_object *obj,
                                  struct drm_property *property, uint64_t val)
{
        int i;

        for (i = 0; i < obj->properties->count; i++) {
                if (obj->properties->properties[i] == property) {
                        obj->properties->values[i] = val;
                        return 0;
                }
        }

        return -EINVAL;
}
EXPORT_SYMBOL(drm_object_property_set_value);

/**
 * drm_object_property_get_value - retrieve the value of a property
 * @obj: drm mode object to get property value from
 * @property: property to retrieve
 * @val: storage for the property value
 *
 * This function retrieves the softare state of the given property for the given
 * property. Since there is no driver callback to retrieve the current property
 * value this might be out of sync with the hardware, depending upon the driver
 * and property.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_object_property_get_value(struct drm_mode_object *obj,
                                  struct drm_property *property, uint64_t *val)
{
        int i;

        /* read-only properties bypass atomic mechanism and still store
         * their value in obj->properties->values[].. mostly to avoid
         * having to deal w/ EDID and similar props in atomic paths:
         */
        if (drm_core_check_feature(property->dev, DRIVER_ATOMIC) &&
                        !(property->flags & DRM_MODE_PROP_IMMUTABLE))
                return drm_atomic_get_property(obj, property, val);

        for (i = 0; i < obj->properties->count; i++) {
                if (obj->properties->properties[i] == property) {
                        *val = obj->properties->values[i];
                        return 0;
                }
        }

        return -EINVAL;
}
EXPORT_SYMBOL(drm_object_property_get_value);

/**
 * drm_mode_getproperty_ioctl - get the property metadata
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the metadata for a given property, like the different
 * possible values for an enum property or the limits for a range property.
 *
 * Blob properties are special
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getproperty_ioctl(struct drm_device *dev,
                               void *data, struct drm_file *file_priv)
{
        struct drm_mode_get_property *out_resp = data;
        struct drm_property *property;
        int enum_count = 0;
        int value_count = 0;
        int ret = 0, i;
        int copied;
        struct drm_property_enum *prop_enum;
        struct drm_mode_property_enum __user *enum_ptr;
        uint64_t __user *values_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        property = drm_property_find(dev, out_resp->prop_id);
        if (!property) {
                ret = -ENOENT;
                goto done;
        }

        if (drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
                        drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
                list_for_each_entry(prop_enum, &property->enum_list, head)
                        enum_count++;
        }

        value_count = property->num_values;

        strncpy(out_resp->name, property->name, DRM_PROP_NAME_LEN);
        out_resp->name[DRM_PROP_NAME_LEN-1] = 0;
        out_resp->flags = property->flags;

        if ((out_resp->count_values >= value_count) && value_count) {
                values_ptr = (uint64_t __user *)(unsigned long)out_resp->values_ptr;
                for (i = 0; i < value_count; i++) {
                        if (copy_to_user(values_ptr + i, &property->values[i], sizeof(uint64_t))) {
                                ret = -EFAULT;
                                goto done;
                        }
                }
        }
        out_resp->count_values = value_count;

        if (drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
                        drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
                if ((out_resp->count_enum_blobs >= enum_count) && enum_count) {
                        copied = 0;
                        enum_ptr = (struct drm_mode_property_enum __user *)(unsigned long)out_resp->enum_blob_ptr;
                        list_for_each_entry(prop_enum, &property->enum_list, head) {

                                if (copy_to_user(&enum_ptr[copied].value, &prop_enum->value, sizeof(uint64_t))) {
                                        ret = -EFAULT;
                                        goto done;
                                }

                                if (copy_to_user(&enum_ptr[copied].name,
                                                 &prop_enum->name, DRM_PROP_NAME_LEN)) {
                                        ret = -EFAULT;
                                        goto done;
                                }
                                copied++;
                        }
                }
                out_resp->count_enum_blobs = enum_count;
        }

        /*
         * NOTE: The idea seems to have been to use this to read all the blob
         * property values. But nothing ever added them to the corresponding
         * list, userspace always used the special-purpose get_blob ioctl to
         * read the value for a blob property. It also doesn't make a lot of
         * sense to return values here when everything else is just metadata for
         * the property itself.
         */
        if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))
                out_resp->count_enum_blobs = 0;
done:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_property_create_blob - Create new blob property
 *
 * Creates a new blob property for a specified DRM device, optionally
 * copying data.
 *
 * @dev: DRM device to create property for
 * @length: Length to allocate for blob data
 * @data: If specified, copies data into blob
 *
 * Returns:
 * New blob property with a single reference on success, or an ERR_PTR
 * value on failure.
 */
struct drm_property_blob *
drm_property_create_blob(struct drm_device *dev, size_t length,
                         const void *data)
{
        struct drm_property_blob *blob;
        int ret;

        if (!length || length > ULONG_MAX - sizeof(struct drm_property_blob))
                return ERR_PTR(-EINVAL);

        blob = kzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL);
        if (!blob)
                return ERR_PTR(-ENOMEM);

        /* This must be explicitly initialised, so we can safely call list_del
         * on it in the removal handler, even if it isn't in a file list. */
        INIT_LIST_HEAD(&blob->head_file);
        blob->length = length;
        blob->dev = dev;

        if (data)
                memcpy(blob->data, data, length);

        mutex_lock(&dev->mode_config.blob_lock);

        ret = drm_mode_object_get(dev, &blob->base, DRM_MODE_OBJECT_BLOB);
        if (ret) {
                kfree(blob);
                mutex_unlock(&dev->mode_config.blob_lock);
                return ERR_PTR(-EINVAL);
        }

        kref_init(&blob->refcount);

        list_add_tail(&blob->head_global,
                      &dev->mode_config.property_blob_list);

        mutex_unlock(&dev->mode_config.blob_lock);

        return blob;
}
EXPORT_SYMBOL(drm_property_create_blob);

/**
 * drm_property_free_blob - Blob property destructor
 *
 * Internal free function for blob properties; must not be used directly.
 *
 * @kref: Reference
 */
static void drm_property_free_blob(struct kref *kref)
{
        struct drm_property_blob *blob =
                container_of(kref, struct drm_property_blob, refcount);

        WARN_ON(!mutex_is_locked(&blob->dev->mode_config.blob_lock));

        list_del(&blob->head_global);
        list_del(&blob->head_file);
        drm_mode_object_put(blob->dev, &blob->base);

        kfree(blob);
}

/**
 * drm_property_unreference_blob - Unreference a blob property
 *
 * Drop a reference on a blob property. May free the object.
 *
 * @blob: Pointer to blob property
 */
void drm_property_unreference_blob(struct drm_property_blob *blob)
{
        struct drm_device *dev;

        if (!blob)
                return;

        dev = blob->dev;

        DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));

        if (kref_put_mutex(&blob->refcount, drm_property_free_blob,
                           &dev->mode_config.blob_lock))
                mutex_unlock(&dev->mode_config.blob_lock);
        else
                might_lock(&dev->mode_config.blob_lock);
}
EXPORT_SYMBOL(drm_property_unreference_blob);

/**
 * drm_property_unreference_blob_locked - Unreference a blob property with blob_lock held
 *
 * Drop a reference on a blob property. May free the object. This must be
 * called with blob_lock held.
 *
 * @blob: Pointer to blob property
 */
static void drm_property_unreference_blob_locked(struct drm_property_blob *blob)
{
        if (!blob)
                return;

        DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));

        kref_put(&blob->refcount, drm_property_free_blob);
}

/**
 * drm_property_destroy_user_blobs - destroy all blobs created by this client
 * @dev:       DRM device
 * @file_priv: destroy all blobs owned by this file handle
 */
void drm_property_destroy_user_blobs(struct drm_device *dev,
                                     struct drm_file *file_priv)
{
        struct drm_property_blob *blob, *bt;

        mutex_lock(&dev->mode_config.blob_lock);

        list_for_each_entry_safe(blob, bt, &file_priv->blobs, head_file) {
                list_del_init(&blob->head_file);
                drm_property_unreference_blob_locked(blob);
        }

        mutex_unlock(&dev->mode_config.blob_lock);
}

/**
 * drm_property_reference_blob - Take a reference on an existing property
 *
 * Take a new reference on an existing blob property.
 *
 * @blob: Pointer to blob property
 */
struct drm_property_blob *drm_property_reference_blob(struct drm_property_blob *blob)
{
        DRM_DEBUG("%p: blob ID: %d (%d)\n", blob, blob->base.id, atomic_read(&blob->refcount.refcount));
        kref_get(&blob->refcount);
        return blob;
}
EXPORT_SYMBOL(drm_property_reference_blob);

/*
 * Like drm_property_lookup_blob, but does not return an additional reference.
 * Must be called with blob_lock held.
 */
static struct drm_property_blob *__drm_property_lookup_blob(struct drm_device *dev,
                                                            uint32_t id)
{
        struct drm_mode_object *obj = NULL;
        struct drm_property_blob *blob;

        WARN_ON(!mutex_is_locked(&dev->mode_config.blob_lock));

        mutex_lock(&dev->mode_config.idr_mutex);
        obj = idr_find(&dev->mode_config.crtc_idr, id);
        if (!obj || (obj->type != DRM_MODE_OBJECT_BLOB) || (obj->id != id))
                blob = NULL;
        else
                blob = obj_to_blob(obj);
        mutex_unlock(&dev->mode_config.idr_mutex);

        return blob;
}

/**
 * drm_property_lookup_blob - look up a blob property and take a reference
 * @dev: drm device
 * @id: id of the blob property
 *
 * If successful, this takes an additional reference to the blob property.
 * callers need to make sure to eventually unreference the returned property
 * again, using @drm_property_unreference_blob.
 */
struct drm_property_blob *drm_property_lookup_blob(struct drm_device *dev,
                                                   uint32_t id)
{
        struct drm_property_blob *blob;

        mutex_lock(&dev->mode_config.blob_lock);
        blob = __drm_property_lookup_blob(dev, id);
        if (blob) {
                if (!kref_get_unless_zero(&blob->refcount))
                        blob = NULL;
        }
        mutex_unlock(&dev->mode_config.blob_lock);

        return blob;
}
EXPORT_SYMBOL(drm_property_lookup_blob);

/**
 * drm_property_replace_global_blob - atomically replace existing blob property
 * @dev: drm device
 * @replace: location of blob property pointer to be replaced
 * @length: length of data for new blob, or 0 for no data
 * @data: content for new blob, or NULL for no data
 * @obj_holds_id: optional object for property holding blob ID
 * @prop_holds_id: optional property holding blob ID
 * @return 0 on success or error on failure
 *
 * This function will atomically replace a global property in the blob list,
 * optionally updating a property which holds the ID of that property. It is
 * guaranteed to be atomic: no caller will be allowed to see intermediate
 * results, and either the entire operation will succeed and clean up the
 * previous property, or it will fail and the state will be unchanged.
 *
 * If length is 0 or data is NULL, no new blob will be created, and the holding
 * property, if specified, will be set to 0.
 *
 * Access to the replace pointer is assumed to be protected by the caller, e.g.
 * by holding the relevant modesetting object lock for its parent.
 *
 * For example, a drm_connector has a 'PATH' property, which contains the ID
 * of a blob property with the value of the MST path information. Calling this
 * function with replace pointing to the connector's path_blob_ptr, length and
 * data set for the new path information, obj_holds_id set to the connector's
 * base object, and prop_holds_id set to the path property name, will perform
 * a completely atomic update. The access to path_blob_ptr is protected by the
 * caller holding a lock on the connector.
 */
static int drm_property_replace_global_blob(struct drm_device *dev,
                                            struct drm_property_blob **replace,
                                            size_t length,
                                            const void *data,
                                            struct drm_mode_object *obj_holds_id,
                                            struct drm_property *prop_holds_id)
{
        struct drm_property_blob *new_blob = NULL;
        struct drm_property_blob *old_blob = NULL;
        int ret;

        WARN_ON(replace == NULL);

        old_blob = *replace;

        if (length && data) {
                new_blob = drm_property_create_blob(dev, length, data);
                if (IS_ERR(new_blob))
                        return PTR_ERR(new_blob);
        }

        /* This does not need to be synchronised with blob_lock, as the
         * get_properties ioctl locks all modesetting objects, and
         * obj_holds_id must be locked before calling here, so we cannot
         * have its value out of sync with the list membership modified
         * below under blob_lock. */
        if (obj_holds_id) {
                ret = drm_object_property_set_value(obj_holds_id,
                                                    prop_holds_id,
                                                    new_blob ?
                                                        new_blob->base.id : 0);
                if (ret != 0)
                        goto err_created;
        }

        drm_property_unreference_blob(old_blob);
        *replace = new_blob;

        return 0;

err_created:
        drm_property_unreference_blob(new_blob);
        return ret;
}

/**
 * drm_mode_getblob_ioctl - get the contents of a blob property value
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the contents of a blob property. The value stored in
 * an object's blob property is just a normal modeset object id.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_getblob_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
{
        struct drm_mode_get_blob *out_resp = data;
        struct drm_property_blob *blob;
        int ret = 0;
        void __user *blob_ptr;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        mutex_lock(&dev->mode_config.blob_lock);
        blob = __drm_property_lookup_blob(dev, out_resp->blob_id);
        if (!blob) {
                ret = -ENOENT;
                goto done;
        }

        if (out_resp->length == blob->length) {
                blob_ptr = (void __user *)(unsigned long)out_resp->data;
                if (copy_to_user(blob_ptr, blob->data, blob->length)) {
                        ret = -EFAULT;
                        goto done;
                }
        }
        out_resp->length = blob->length;

done:
        mutex_unlock(&dev->mode_config.blob_lock);
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_createblob_ioctl - create a new blob property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function creates a new blob property with user-defined values. In order
 * to give us sensible validation and checking when creating, rather than at
 * every potential use, we also require a type to be provided upfront.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_createblob_ioctl(struct drm_device *dev,
                              void *data, struct drm_file *file_priv)
{
        struct drm_mode_create_blob *out_resp = data;
        struct drm_property_blob *blob;
        void __user *blob_ptr;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        blob = drm_property_create_blob(dev, out_resp->length, NULL);
        if (IS_ERR(blob))
                return PTR_ERR(blob);

        blob_ptr = (void __user *)(unsigned long)out_resp->data;
        if (copy_from_user(blob->data, blob_ptr, out_resp->length)) {
                ret = -EFAULT;
                goto out_blob;
        }

        /* Dropping the lock between create_blob and our access here is safe
         * as only the same file_priv can remove the blob; at this point, it is
         * not associated with any file_priv. */
        mutex_lock(&dev->mode_config.blob_lock);
        out_resp->blob_id = blob->base.id;
        list_add_tail(&blob->head_file, &file_priv->blobs);
        mutex_unlock(&dev->mode_config.blob_lock);

        return 0;

out_blob:
        drm_property_unreference_blob(blob);
        return ret;
}

/**
 * drm_mode_destroyblob_ioctl - destroy a user blob property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Destroy an existing user-defined blob property.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_destroyblob_ioctl(struct drm_device *dev,
                               void *data, struct drm_file *file_priv)
{
        struct drm_mode_destroy_blob *out_resp = data;
        struct drm_property_blob *blob = NULL, *bt;
        bool found = false;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        mutex_lock(&dev->mode_config.blob_lock);
        blob = __drm_property_lookup_blob(dev, out_resp->blob_id);
        if (!blob) {
                ret = -ENOENT;
                goto err;
        }

        /* Ensure the property was actually created by this user. */
        list_for_each_entry(bt, &file_priv->blobs, head_file) {
                if (bt == blob) {
                        found = true;
                        break;
                }
        }

        if (!found) {
                ret = -EPERM;
                goto err;
        }

        /* We must drop head_file here, because we may not be the last
         * reference on the blob. */
        list_del_init(&blob->head_file);
        drm_property_unreference_blob_locked(blob);
        mutex_unlock(&dev->mode_config.blob_lock);

        return 0;

err:
        mutex_unlock(&dev->mode_config.blob_lock);
        return ret;
}

/**
 * drm_mode_connector_set_path_property - set tile property on connector
 * @connector: connector to set property on.
 * @path: path to use for property; must not be NULL.
 *
 * This creates a property to expose to userspace to specify a
 * connector path. This is mainly used for DisplayPort MST where
 * connectors have a topology and we want to allow userspace to give
 * them more meaningful names.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_connector_set_path_property(struct drm_connector *connector,
                                         const char *path)
{
        struct drm_device *dev = connector->dev;
        int ret;

        ret = drm_property_replace_global_blob(dev,
                                               &connector->path_blob_ptr,
                                               strlen(path) + 1,
                                               path,
                                               &connector->base,
                                               dev->mode_config.path_property);
        return ret;
}
EXPORT_SYMBOL(drm_mode_connector_set_path_property);

/**
 * drm_mode_connector_set_tile_property - set tile property on connector
 * @connector: connector to set property on.
 *
 * This looks up the tile information for a connector, and creates a
 * property for userspace to parse if it exists. The property is of
 * the form of 8 integers using ':' as a separator.
 *
 * Returns:
 * Zero on success, errno on failure.
 */
int drm_mode_connector_set_tile_property(struct drm_connector *connector)
{
        struct drm_device *dev = connector->dev;
        char tile[256];
        int ret;

        if (!connector->has_tile) {
                ret  = drm_property_replace_global_blob(dev,
                                                        &connector->tile_blob_ptr,
                                                        0,
                                                        NULL,
                                                        &connector->base,
                                                        dev->mode_config.tile_property);
                return ret;
        }

        snprintf(tile, 256, "%d:%d:%d:%d:%d:%d:%d:%d",
                 connector->tile_group->id, connector->tile_is_single_monitor,
                 connector->num_h_tile, connector->num_v_tile,
                 connector->tile_h_loc, connector->tile_v_loc,
                 connector->tile_h_size, connector->tile_v_size);

        ret = drm_property_replace_global_blob(dev,
                                               &connector->tile_blob_ptr,
                                               strlen(tile) + 1,
                                               tile,
                                               &connector->base,
                                               dev->mode_config.tile_property);
        return ret;
}
EXPORT_SYMBOL(drm_mode_connector_set_tile_property);

/**
 * drm_mode_connector_update_edid_property - update the edid property of a connector
 * @connector: drm connector
 * @edid: new value of the edid property
 *
 * This function creates a new blob modeset object and assigns its id to the
 * connector's edid property.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_connector_update_edid_property(struct drm_connector *connector,
                                            const struct edid *edid)
{
        struct drm_device *dev = connector->dev;
        size_t size = 0;
        int ret;

        /* ignore requests to set edid when overridden */
        if (connector->override_edid)
                return 0;

        if (edid)
                size = EDID_LENGTH * (1 + edid->extensions);

        ret = drm_property_replace_global_blob(dev,
                                               &connector->edid_blob_ptr,
                                               size,
                                               edid,
                                               &connector->base,
                                               dev->mode_config.edid_property);
        return ret;
}
EXPORT_SYMBOL(drm_mode_connector_update_edid_property);

/* Some properties could refer to dynamic refcnt'd objects, or things that
 * need special locking to handle lifetime issues (ie. to ensure the prop
 * value doesn't become invalid part way through the property update due to
 * race).  The value returned by reference via 'obj' should be passed back
 * to drm_property_change_valid_put() after the property is set (and the
 * object to which the property is attached has a chance to take it's own
 * reference).
 */
bool drm_property_change_valid_get(struct drm_property *property,
                                         uint64_t value, struct drm_mode_object **ref)
{
        int i;

        if (property->flags & DRM_MODE_PROP_IMMUTABLE)
                return false;

        *ref = NULL;

        if (drm_property_type_is(property, DRM_MODE_PROP_RANGE)) {
                if (value < property->values[0] || value > property->values[1])
                        return false;
                return true;
        } else if (drm_property_type_is(property, DRM_MODE_PROP_SIGNED_RANGE)) {
                int64_t svalue = U642I64(value);

                if (svalue < U642I64(property->values[0]) ||
                                svalue > U642I64(property->values[1]))
                        return false;
                return true;
        } else if (drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
                uint64_t valid_mask = 0;

                for (i = 0; i < property->num_values; i++)
                        valid_mask |= (1ULL << property->values[i]);
                return !(value & ~valid_mask);
        } else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
                struct drm_property_blob *blob;

                if (value == 0)
                        return true;

                blob = drm_property_lookup_blob(property->dev, value);
                if (blob) {
                        *ref = &blob->base;
                        return true;
                } else {
                        return false;
                }
        } else if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
                /* a zero value for an object property translates to null: */
                if (value == 0)
                        return true;

                /* handle refcnt'd objects specially: */
                if (property->values[0] == DRM_MODE_OBJECT_FB) {
                        struct drm_framebuffer *fb;
                        fb = drm_framebuffer_lookup(property->dev, value);
                        if (fb) {
                                *ref = &fb->base;
                                return true;
                        } else {
                                return false;
                        }
                } else {
                        return _object_find(property->dev, value, property->values[0]) != NULL;
                }
        }

        for (i = 0; i < property->num_values; i++)
                if (property->values[i] == value)
                        return true;
        return false;
}

void drm_property_change_valid_put(struct drm_property *property,
                struct drm_mode_object *ref)
{
        if (!ref)
                return;

        if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
                if (property->values[0] == DRM_MODE_OBJECT_FB)
                        drm_framebuffer_unreference(obj_to_fb(ref));
        } else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))
                drm_property_unreference_blob(obj_to_blob(ref));
}

/**
 * drm_mode_connector_property_set_ioctl - set the current value of a connector property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function sets the current value for a connectors's property. It also
 * calls into a driver's ->set_property callback to update the hardware state
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_connector_property_set_ioctl(struct drm_device *dev,
                                       void *data, struct drm_file *file_priv)
{
        struct drm_mode_connector_set_property *conn_set_prop = data;
        struct drm_mode_obj_set_property obj_set_prop = {
                .value = conn_set_prop->value,
                .prop_id = conn_set_prop->prop_id,
                .obj_id = conn_set_prop->connector_id,
                .obj_type = DRM_MODE_OBJECT_CONNECTOR
        };

        /* It does all the locking and checking we need */
        return drm_mode_obj_set_property_ioctl(dev, &obj_set_prop, file_priv);
}

static int drm_mode_connector_set_obj_prop(struct drm_mode_object *obj,
                                           struct drm_property *property,
                                           uint64_t value)
{
        int ret = -EINVAL;
        struct drm_connector *connector = obj_to_connector(obj);

        /* Do DPMS ourselves */
        if (property == connector->dev->mode_config.dpms_property) {
                ret = 0;
                if (connector->funcs->dpms)
                        ret = (*connector->funcs->dpms)(connector, (int)value);
        } else if (connector->funcs->set_property)
                ret = connector->funcs->set_property(connector, property, value);

        /* store the property value if successful */
        if (!ret)
                drm_object_property_set_value(&connector->base, property, value);
        return ret;
}

static int drm_mode_crtc_set_obj_prop(struct drm_mode_object *obj,
                                      struct drm_property *property,
                                      uint64_t value)
{
        int ret = -EINVAL;
        struct drm_crtc *crtc = obj_to_crtc(obj);

        if (crtc->funcs->set_property)
                ret = crtc->funcs->set_property(crtc, property, value);
        if (!ret)
                drm_object_property_set_value(obj, property, value);

        return ret;
}

/**
 * drm_mode_plane_set_obj_prop - set the value of a property
 * @plane: drm plane object to set property value for
 * @property: property to set
 * @value: value the property should be set to
 *
 * This functions sets a given property on a given plane object. This function
 * calls the driver's ->set_property callback and changes the software state of
 * the property if the callback succeeds.
 *
 * Returns:
 * Zero on success, error code on failure.
 */
int drm_mode_plane_set_obj_prop(struct drm_plane *plane,
                                struct drm_property *property,
                                uint64_t value)
{
        int ret = -EINVAL;
        struct drm_mode_object *obj = &plane->base;

        if (plane->funcs->set_property)
                ret = plane->funcs->set_property(plane, property, value);
        if (!ret)
                drm_object_property_set_value(obj, property, value);

        return ret;
}
EXPORT_SYMBOL(drm_mode_plane_set_obj_prop);

/**
 * drm_mode_obj_get_properties_ioctl - get the current value of a object's property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function retrieves the current value for an object's property. Compared
 * to the connector specific ioctl this one is extended to also work on crtc and
 * plane objects.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
                                      struct drm_file *file_priv)
{
        struct drm_mode_obj_get_properties *arg = data;
        struct drm_mode_object *obj;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);

        obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
        if (!obj) {
                ret = -ENOENT;
                goto out;
        }
        if (!obj->properties) {
                ret = -EINVAL;
                goto out;
        }

        ret = get_properties(obj, file_priv->atomic,
                        (uint32_t __user *)(unsigned long)(arg->props_ptr),
                        (uint64_t __user *)(unsigned long)(arg->prop_values_ptr),
                        &arg->count_props);

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_obj_set_property_ioctl - set the current value of an object's property
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This function sets the current value for an object's property. It also calls
 * into a driver's ->set_property callback to update the hardware state.
 * Compared to the connector specific ioctl this one is extended to also work on
 * crtc and plane objects.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
                                    struct drm_file *file_priv)
{
        struct drm_mode_obj_set_property *arg = data;
        struct drm_mode_object *arg_obj;
        struct drm_mode_object *prop_obj;
        struct drm_property *property;
        int i, ret = -EINVAL;
        struct drm_mode_object *ref;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);

        arg_obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
        if (!arg_obj) {
                ret = -ENOENT;
                goto out;
        }
        if (!arg_obj->properties)
                goto out;

        for (i = 0; i < arg_obj->properties->count; i++)
                if (arg_obj->properties->properties[i]->base.id == arg->prop_id)
                        break;

        if (i == arg_obj->properties->count)
                goto out;

        prop_obj = drm_mode_object_find(dev, arg->prop_id,
                                        DRM_MODE_OBJECT_PROPERTY);
        if (!prop_obj) {
                ret = -ENOENT;
                goto out;
        }
        property = obj_to_property(prop_obj);

        if (!drm_property_change_valid_get(property, arg->value, &ref))
                goto out;

        switch (arg_obj->type) {
        case DRM_MODE_OBJECT_CONNECTOR:
                ret = drm_mode_connector_set_obj_prop(arg_obj, property,
                                                      arg->value);
                break;
        case DRM_MODE_OBJECT_CRTC:
                ret = drm_mode_crtc_set_obj_prop(arg_obj, property, arg->value);
                break;
        case DRM_MODE_OBJECT_PLANE:
                ret = drm_mode_plane_set_obj_prop(obj_to_plane(arg_obj),
                                                  property, arg->value);
                break;
        }

        drm_property_change_valid_put(property, ref);

out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_connector_attach_encoder - attach a connector to an encoder
 * @connector: connector to attach
 * @encoder: encoder to attach @connector to
 *
 * This function links up a connector to an encoder. Note that the routing
 * restrictions between encoders and crtcs are exposed to userspace through the
 * possible_clones and possible_crtcs bitmasks.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_connector_attach_encoder(struct drm_connector *connector,
                                      struct drm_encoder *encoder)
{
        int i;

        /*
         * In the past, drivers have attempted to model the static association
         * of connector to encoder in simple connector/encoder devices using a
         * direct assignment of connector->encoder = encoder. This connection
         * is a logical one and the responsibility of the core, so drivers are
         * expected not to mess with this.
         *
         * Note that the error return should've been enough here, but a large
         * majority of drivers ignores the return value, so add in a big WARN
         * to get people's attention.
         */
        if (WARN_ON(connector->encoder))
                return -EINVAL;

        for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
                if (connector->encoder_ids[i] == 0) {
                        connector->encoder_ids[i] = encoder->base.id;
                        return 0;
                }
        }
        return -ENOMEM;
}
EXPORT_SYMBOL(drm_mode_connector_attach_encoder);

/**
 * drm_mode_crtc_set_gamma_size - set the gamma table size
 * @crtc: CRTC to set the gamma table size for
 * @gamma_size: size of the gamma table
 *
 * Drivers which support gamma tables should set this to the supported gamma
 * table size when initializing the CRTC. Currently the drm core only supports a
 * fixed gamma table size.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
                                 int gamma_size)
{
        crtc->gamma_size = gamma_size;

        crtc->gamma_store = kcalloc(gamma_size, sizeof(uint16_t) * 3,
                                    GFP_KERNEL);
        if (!crtc->gamma_store) {
                crtc->gamma_size = 0;
                return -ENOMEM;
        }

        return 0;
}
EXPORT_SYMBOL(drm_mode_crtc_set_gamma_size);

/**
 * drm_mode_gamma_set_ioctl - set the gamma table
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Set the gamma table of a CRTC to the one passed in by the user. Userspace can
 * inquire the required gamma table size through drm_mode_gamma_get_ioctl.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_gamma_set_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_lut *crtc_lut = data;
        struct drm_crtc *crtc;
        void *r_base, *g_base, *b_base;
        int size;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        crtc = drm_crtc_find(dev, crtc_lut->crtc_id);
        if (!crtc) {
                ret = -ENOENT;
                goto out;
        }

        if (crtc->funcs->gamma_set == NULL) {
                ret = -ENOSYS;
                goto out;
        }

        /* memcpy into gamma store */
        if (crtc_lut->gamma_size != crtc->gamma_size) {
                ret = -EINVAL;
                goto out;
        }

        size = crtc_lut->gamma_size * (sizeof(uint16_t));
        r_base = crtc->gamma_store;
        if (copy_from_user(r_base, (void __user *)(unsigned long)crtc_lut->red, size)) {
                ret = -EFAULT;
                goto out;
        }

        g_base = r_base + size;
        if (copy_from_user(g_base, (void __user *)(unsigned long)crtc_lut->green, size)) {
                ret = -EFAULT;
                goto out;
        }

        b_base = g_base + size;
        if (copy_from_user(b_base, (void __user *)(unsigned long)crtc_lut->blue, size)) {
                ret = -EFAULT;
                goto out;
        }

        crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);

out:
        drm_modeset_unlock_all(dev);
        return ret;

}

/**
 * drm_mode_gamma_get_ioctl - get the gamma table
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Copy the current gamma table into the storage provided. This also provides
 * the gamma table size the driver expects, which can be used to size the
 * allocated storage.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_gamma_get_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_lut *crtc_lut = data;
        struct drm_crtc *crtc;
        void *r_base, *g_base, *b_base;
        int size;
        int ret = 0;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        drm_modeset_lock_all(dev);
        crtc = drm_crtc_find(dev, crtc_lut->crtc_id);
        if (!crtc) {
                ret = -ENOENT;
                goto out;
        }

        /* memcpy into gamma store */
        if (crtc_lut->gamma_size != crtc->gamma_size) {
                ret = -EINVAL;
                goto out;
        }

        size = crtc_lut->gamma_size * (sizeof(uint16_t));
        r_base = crtc->gamma_store;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->red, r_base, size)) {
                ret = -EFAULT;
                goto out;
        }

        g_base = r_base + size;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->green, g_base, size)) {
                ret = -EFAULT;
                goto out;
        }

        b_base = g_base + size;
        if (copy_to_user((void __user *)(unsigned long)crtc_lut->blue, b_base, size)) {
                ret = -EFAULT;
                goto out;
        }
out:
        drm_modeset_unlock_all(dev);
        return ret;
}

/**
 * drm_mode_page_flip_ioctl - schedule an asynchronous fb update
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This schedules an asynchronous update on a given CRTC, called page flip.
 * Optionally a drm event is generated to signal the completion of the event.
 * Generic drivers cannot assume that a pageflip with changed framebuffer
 * properties (including driver specific metadata like tiling layout) will work,
 * but some drivers support e.g. pixel format changes through the pageflip
 * ioctl.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_page_flip_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_crtc_page_flip *page_flip = data;
        struct drm_crtc *crtc;
        struct drm_framebuffer *fb = NULL;
        struct drm_pending_vblank_event *e = NULL;
        unsigned long flags;
        int ret = -EINVAL;

        if (!drm_core_check_feature(dev, DRIVER_MODESET))
                return -EINVAL;

        if (page_flip->flags & ~DRM_MODE_PAGE_FLIP_FLAGS ||
            page_flip->reserved != 0)
                return -EINVAL;

        if ((page_flip->flags & DRM_MODE_PAGE_FLIP_ASYNC) && !dev->mode_config.async_page_flip)
                return -EINVAL;

        crtc = drm_crtc_find(dev, page_flip->crtc_id);
        if (!crtc)
                return -ENOENT;

        drm_modeset_lock_crtc(crtc, crtc->primary);
        if (crtc->primary->fb == NULL) {
                /* The framebuffer is currently unbound, presumably
                 * due to a hotplug event, that userspace has not
                 * yet discovered.
                 */
                ret = -EBUSY;
                goto out;
        }

        if (crtc->funcs->page_flip == NULL)
                goto out;

        fb = drm_framebuffer_lookup(dev, page_flip->fb_id);
        if (!fb) {
                ret = -ENOENT;
                goto out;
        }

        if (crtc->state) {
                const struct drm_plane_state *state = crtc->primary->state;

                ret = check_src_coords(state->src_x, state->src_y,
                                       state->src_w, state->src_h, fb);
        } else {
                ret = drm_crtc_check_viewport(crtc, crtc->x, crtc->y, &crtc->mode, fb);
        }
        if (ret)
                goto out;

        if (crtc->primary->fb->pixel_format != fb->pixel_format) {
                DRM_DEBUG_KMS("Page flip is not allowed to change frame buffer format.\n");
                ret = -EINVAL;
                goto out;
        }

        if (page_flip->flags & DRM_MODE_PAGE_FLIP_EVENT) {
                ret = -ENOMEM;
                spin_lock_irqsave(&dev->event_lock, flags);
                if (file_priv->event_space < sizeof(e->event)) {
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        goto out;
                }
                file_priv->event_space -= sizeof(e->event);
                spin_unlock_irqrestore(&dev->event_lock, flags);

                e = kzalloc(sizeof(*e), GFP_KERNEL);
                if (e == NULL) {
                        spin_lock_irqsave(&dev->event_lock, flags);
                        file_priv->event_space += sizeof(e->event);
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        goto out;
                }

                e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
                e->event.base.length = sizeof(e->event);
                e->event.user_data = page_flip->user_data;
                e->base.event = &e->event.base;
                e->base.file_priv = file_priv;
                e->base.destroy =
                        (void (*) (struct drm_pending_event *)) kfree;
        }

        crtc->primary->old_fb = crtc->primary->fb;
        ret = crtc->funcs->page_flip(crtc, fb, e, page_flip->flags);
        if (ret) {
                if (page_flip->flags & DRM_MODE_PAGE_FLIP_EVENT) {
                        spin_lock_irqsave(&dev->event_lock, flags);
                        file_priv->event_space += sizeof(e->event);
                        spin_unlock_irqrestore(&dev->event_lock, flags);
                        kfree(e);
                }
                /* Keep the old fb, don't unref it. */
                crtc->primary->old_fb = NULL;
        } else {
                crtc->primary->fb = fb;
                /* Unref only the old framebuffer. */
                fb = NULL;
        }

out:
        if (fb)
                drm_framebuffer_unreference(fb);
        if (crtc->primary->old_fb)
                drm_framebuffer_unreference(crtc->primary->old_fb);
        crtc->primary->old_fb = NULL;
        drm_modeset_unlock_crtc(crtc);

        return ret;
}

/**
 * drm_mode_config_reset - call ->reset callbacks
 * @dev: drm device
 *
 * This functions calls all the crtc's, encoder's and connector's ->reset
 * callback. Drivers can use this in e.g. their driver load or resume code to
 * reset hardware and software state.
 */
void drm_mode_config_reset(struct drm_device *dev)
{
        struct drm_crtc *crtc;
        struct drm_plane *plane;
        struct drm_encoder *encoder;
        struct drm_connector *connector;

        drm_for_each_plane(plane, dev)
                if (plane->funcs->reset)
                        plane->funcs->reset(plane);

        drm_for_each_crtc(crtc, dev)
                if (crtc->funcs->reset)
                        crtc->funcs->reset(crtc);

        drm_for_each_encoder(encoder, dev)
                if (encoder->funcs->reset)
                        encoder->funcs->reset(encoder);

        mutex_lock(&dev->mode_config.mutex);
        drm_for_each_connector(connector, dev)
                if (connector->funcs->reset)
                        connector->funcs->reset(connector);
        mutex_unlock(&dev->mode_config.mutex);
}
EXPORT_SYMBOL(drm_mode_config_reset);

/**
 * drm_mode_create_dumb_ioctl - create a dumb backing storage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This creates a new dumb buffer in the driver's backing storage manager (GEM,
 * TTM or something else entirely) and returns the resulting buffer handle. This
 * handle can then be wrapped up into a framebuffer modeset object.
 *
 * Note that userspace is not allowed to use such objects for render
 * acceleration - drivers must create their own private ioctls for such a use
 * case.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_create_dumb_ioctl(struct drm_device *dev,
                               void *data, struct drm_file *file_priv)
{
        struct drm_mode_create_dumb *args = data;
        u32 cpp, stride, size;

        if (!dev->driver->dumb_create)
                return -ENOSYS;
        if (!args->width || !args->height || !args->bpp)
                return -EINVAL;

        /* overflow checks for 32bit size calculations */
        /* NOTE: DIV_ROUND_UP() can overflow */
        cpp = DIV_ROUND_UP(args->bpp, 8);
        if (!cpp || cpp > 0xffffffffU / args->width)
                return -EINVAL;
        stride = cpp * args->width;
        if (args->height > 0xffffffffU / stride)
                return -EINVAL;

        /* test for wrap-around */
        size = args->height * stride;
        if (PAGE_ALIGN(size) == 0)
                return -EINVAL;

        /*
         * handle, pitch and size are output parameters. Zero them out to
         * prevent drivers from accidentally using uninitialized data. Since
         * not all existing userspace is clearing these fields properly we
         * cannot reject IOCTL with garbage in them.
         */
        args->handle = 0;
        args->pitch = 0;
        args->size = 0;

        return dev->driver->dumb_create(file_priv, dev, args);
}

/**
 * drm_mode_mmap_dumb_ioctl - create an mmap offset for a dumb backing storage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * Allocate an offset in the drm device node's address space to be able to
 * memory map a dumb buffer.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_mmap_dumb_ioctl(struct drm_device *dev,
                             void *data, struct drm_file *file_priv)
{
        struct drm_mode_map_dumb *args = data;

        /* call driver ioctl to get mmap offset */
        if (!dev->driver->dumb_map_offset)
                return -ENOSYS;

        return dev->driver->dumb_map_offset(file_priv, dev, args->handle, &args->offset);
}

/**
 * drm_mode_destroy_dumb_ioctl - destroy a dumb backing strage buffer
 * @dev: DRM device
 * @data: ioctl data
 * @file_priv: DRM file info
 *
 * This destroys the userspace handle for the given dumb backing storage buffer.
 * Since buffer objects must be reference counted in the kernel a buffer object
 * won't be immediately freed if a framebuffer modeset object still uses it.
 *
 * Called by the user via ioctl.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_destroy_dumb_ioctl(struct drm_device *dev,
                                void *data, struct drm_file *file_priv)
{
        struct drm_mode_destroy_dumb *args = data;

        if (!dev->driver->dumb_destroy)
                return -ENOSYS;

        return dev->driver->dumb_destroy(file_priv, dev, args->handle);
}

/**
 * drm_fb_get_bpp_depth - get the bpp/depth values for format
 * @format: pixel format (DRM_FORMAT_*)
 * @depth: storage for the depth value
 * @bpp: storage for the bpp value
 *
 * This only supports RGB formats here for compat with code that doesn't use
 * pixel formats directly yet.
 */
void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth,
                          int *bpp)
{
        switch (format) {
        case DRM_FORMAT_C8:
        case DRM_FORMAT_RGB332:
        case DRM_FORMAT_BGR233:
                *depth = 8;
                *bpp = 8;
                break;
        case DRM_FORMAT_XRGB1555:
        case DRM_FORMAT_XBGR1555:
        case DRM_FORMAT_RGBX5551:
        case DRM_FORMAT_BGRX5551:
        case DRM_FORMAT_ARGB1555:
        case DRM_FORMAT_ABGR1555:
        case DRM_FORMAT_RGBA5551:
        case DRM_FORMAT_BGRA5551:
                *depth = 15;
                *bpp = 16;
                break;
        case DRM_FORMAT_RGB565:
        case DRM_FORMAT_BGR565:
                *depth = 16;
                *bpp = 16;
                break;
        case DRM_FORMAT_RGB888:
        case DRM_FORMAT_BGR888:
                *depth = 24;
                *bpp = 24;
                break;
        case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_XBGR8888:
        case DRM_FORMAT_RGBX8888:
        case DRM_FORMAT_BGRX8888:
                *depth = 24;
                *bpp = 32;
                break;
        case DRM_FORMAT_XRGB2101010:
        case DRM_FORMAT_XBGR2101010:
        case DRM_FORMAT_RGBX1010102:
        case DRM_FORMAT_BGRX1010102:
        case DRM_FORMAT_ARGB2101010:
        case DRM_FORMAT_ABGR2101010:
        case DRM_FORMAT_RGBA1010102:
        case DRM_FORMAT_BGRA1010102:
                *depth = 30;
                *bpp = 32;
                break;
        case DRM_FORMAT_ARGB8888:
        case DRM_FORMAT_ABGR8888:
        case DRM_FORMAT_RGBA8888:
        case DRM_FORMAT_BGRA8888:
                *depth = 32;
                *bpp = 32;
                break;
        default:
                DRM_DEBUG_KMS("unsupported pixel format %s\n",
                              drm_get_format_name(format));
                *depth = 0;
                *bpp = 0;
                break;
        }
}
EXPORT_SYMBOL(drm_fb_get_bpp_depth);

/**
 * drm_format_num_planes - get the number of planes for format
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The number of planes used by the specified pixel format.
 */
int drm_format_num_planes(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 3;
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
        case DRM_FORMAT_NV12_10:
        case DRM_FORMAT_NV21_10:
        case DRM_FORMAT_NV16_10:
        case DRM_FORMAT_NV61_10:
        case DRM_FORMAT_NV24_10:
        case DRM_FORMAT_NV42_10:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_num_planes);

/**
 * drm_format_plane_bpp - get the bpp for format
 * @format: pixel format (DRM_FORMAT_*)
 * @plane: plane index
 *
 * Returns:
 * The bpp for the specified plane.
 */
int drm_format_plane_bpp(uint32_t format, int plane)
{
        unsigned int depth;
        int bpp;

        if (plane >= drm_format_num_planes(format))
                return 0;

        switch (format) {
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
                return 16;
        case DRM_FORMAT_NV12_10:
        case DRM_FORMAT_NV21_10:
        case DRM_FORMAT_NV16_10:
        case DRM_FORMAT_NV61_10:
        case DRM_FORMAT_NV24_10:
        case DRM_FORMAT_NV42_10:
                return plane ? 20 : 10;
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV24:
        case DRM_FORMAT_NV42:
                return plane ? 16 : 8;
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV444:
        case DRM_FORMAT_YVU444:
                return 8;
        default:
                drm_fb_get_bpp_depth(format, &depth, &bpp);
                return bpp;
        }
}
EXPORT_SYMBOL(drm_format_plane_bpp);

/**
 * drm_format_plane_cpp - determine the bytes per pixel value
 * @format: pixel format (DRM_FORMAT_*)
 * @plane: plane index
 *
 * Returns:
 * The bytes per pixel value for the specified plane.
 */
int drm_format_plane_cpp(uint32_t format, int plane)
{
        return drm_format_plane_bpp(format, plane) >> 3;
}
EXPORT_SYMBOL(drm_format_plane_cpp);

/**
 * drm_format_horz_chroma_subsampling - get the horizontal chroma subsampling factor
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The horizontal chroma subsampling factor for the
 * specified pixel format.
 */
int drm_format_horz_chroma_subsampling(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV411:
        case DRM_FORMAT_YVU411:
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
                return 4;
        case DRM_FORMAT_YUYV:
        case DRM_FORMAT_YVYU:
        case DRM_FORMAT_UYVY:
        case DRM_FORMAT_VYUY:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV16:
        case DRM_FORMAT_NV61:
        case DRM_FORMAT_NV12_10:
        case DRM_FORMAT_NV21_10:
        case DRM_FORMAT_NV16_10:
        case DRM_FORMAT_NV61_10:
        case DRM_FORMAT_YUV422:
        case DRM_FORMAT_YVU422:
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_horz_chroma_subsampling);

/**
 * drm_format_vert_chroma_subsampling - get the vertical chroma subsampling factor
 * @format: pixel format (DRM_FORMAT_*)
 *
 * Returns:
 * The vertical chroma subsampling factor for the
 * specified pixel format.
 */
int drm_format_vert_chroma_subsampling(uint32_t format)
{
        switch (format) {
        case DRM_FORMAT_YUV410:
        case DRM_FORMAT_YVU410:
                return 4;
        case DRM_FORMAT_YUV420:
        case DRM_FORMAT_YVU420:
        case DRM_FORMAT_NV12:
        case DRM_FORMAT_NV12_10:
        case DRM_FORMAT_NV21:
        case DRM_FORMAT_NV21_10:
                return 2;
        default:
                return 1;
        }
}
EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);

/**
 * drm_rotation_simplify() - Try to simplify the rotation
 * @rotation: Rotation to be simplified
 * @supported_rotations: Supported rotations
 *
 * Attempt to simplify the rotation to a form that is supported.
 * Eg. if the hardware supports everything except DRM_REFLECT_X
 * one could call this function like this:
 *
 * drm_rotation_simplify(rotation, BIT(DRM_ROTATE_0) |
 *                       BIT(DRM_ROTATE_90) | BIT(DRM_ROTATE_180) |
 *                       BIT(DRM_ROTATE_270) | BIT(DRM_REFLECT_Y));
 *
 * to eliminate the DRM_ROTATE_X flag. Depending on what kind of
 * transforms the hardware supports, this function may not
 * be able to produce a supported transform, so the caller should
 * check the result afterwards.
 */
unsigned int drm_rotation_simplify(unsigned int rotation,
                                   unsigned int supported_rotations)
{
        if (rotation & ~supported_rotations) {
                rotation ^= BIT(DRM_REFLECT_X) | BIT(DRM_REFLECT_Y);
                rotation = (rotation & DRM_REFLECT_MASK) |
                           BIT((ffs(rotation & DRM_ROTATE_MASK) + 1) % 4);
        }

        return rotation;
}
EXPORT_SYMBOL(drm_rotation_simplify);

/**
 * drm_mode_config_init - initialize DRM mode_configuration structure
 * @dev: DRM device
 *
 * Initialize @dev's mode_config structure, used for tracking the graphics
 * configuration of @dev.
 *
 * Since this initializes the modeset locks, no locking is possible. Which is no
 * problem, since this should happen single threaded at init time. It is the
 * driver's problem to ensure this guarantee.
 *
 */
void drm_mode_config_init(struct drm_device *dev)
{
        mutex_init(&dev->mode_config.mutex);
        drm_modeset_lock_init(&dev->mode_config.connection_mutex);
        mutex_init(&dev->mode_config.idr_mutex);
        mutex_init(&dev->mode_config.fb_lock);
        mutex_init(&dev->mode_config.blob_lock);
        INIT_LIST_HEAD(&dev->mode_config.fb_list);
        INIT_LIST_HEAD(&dev->mode_config.crtc_list);
        INIT_LIST_HEAD(&dev->mode_config.connector_list);
        INIT_LIST_HEAD(&dev->mode_config.encoder_list);
        INIT_LIST_HEAD(&dev->mode_config.property_list);
        INIT_LIST_HEAD(&dev->mode_config.property_blob_list);
        INIT_LIST_HEAD(&dev->mode_config.plane_list);
        idr_init(&dev->mode_config.crtc_idr);
        idr_init(&dev->mode_config.tile_idr);

        drm_modeset_lock_all(dev);
        drm_mode_create_standard_properties(dev);
        drm_modeset_unlock_all(dev);

        /* Just to be sure */
        dev->mode_config.num_fb = 0;
        dev->mode_config.num_connector = 0;
        dev->mode_config.num_crtc = 0;
        dev->mode_config.num_encoder = 0;
        dev->mode_config.num_overlay_plane = 0;
        dev->mode_config.num_total_plane = 0;
}
EXPORT_SYMBOL(drm_mode_config_init);

/**
 * drm_mode_config_cleanup - free up DRM mode_config info
 * @dev: DRM device
 *
 * Free up all the connectors and CRTCs associated with this DRM device, then
 * free up the framebuffers and associated buffer objects.
 *
 * Note that since this /should/ happen single-threaded at driver/device
 * teardown time, no locking is required. It's the driver's job to ensure that
 * this guarantee actually holds true.
 *
 * FIXME: cleanup any dangling user buffer objects too
 */
void drm_mode_config_cleanup(struct drm_device *dev)
{
        struct drm_connector *connector, *ot;
        struct drm_crtc *crtc, *ct;
        struct drm_encoder *encoder, *enct;
        struct drm_framebuffer *fb, *fbt;
        struct drm_property *property, *pt;
        struct drm_property_blob *blob, *bt;
        struct drm_plane *plane, *plt;

        list_for_each_entry_safe(encoder, enct, &dev->mode_config.encoder_list,
                                 head) {
                encoder->funcs->destroy(encoder);
        }

        list_for_each_entry_safe(connector, ot,
                                 &dev->mode_config.connector_list, head) {
                connector->funcs->destroy(connector);
        }

        list_for_each_entry_safe(property, pt, &dev->mode_config.property_list,
                                 head) {
                drm_property_destroy(dev, property);
        }

        list_for_each_entry_safe(blob, bt, &dev->mode_config.property_blob_list,
                                 head_global) {
                drm_property_unreference_blob(blob);
        }

        /*
         * Single-threaded teardown context, so it's not required to grab the
         * fb_lock to protect against concurrent fb_list access. Contrary, it
         * would actually deadlock with the drm_framebuffer_cleanup function.
         *
         * Also, if there are any framebuffers left, that's a driver leak now,
         * so politely WARN about this.
         */
        WARN_ON(!list_empty(&dev->mode_config.fb_list));
        list_for_each_entry_safe(fb, fbt, &dev->mode_config.fb_list, head) {
                drm_framebuffer_free(&fb->refcount);
        }

        list_for_each_entry_safe(plane, plt, &dev->mode_config.plane_list,
                                 head) {
                plane->funcs->destroy(plane);
        }

        list_for_each_entry_safe(crtc, ct, &dev->mode_config.crtc_list, head) {
                crtc->funcs->destroy(crtc);
        }

        idr_destroy(&dev->mode_config.tile_idr);
        idr_destroy(&dev->mode_config.crtc_idr);
        drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
}
EXPORT_SYMBOL(drm_mode_config_cleanup);

struct drm_property *drm_mode_create_rotation_property(struct drm_device *dev,
                                                       unsigned int supported_rotations)
{
        static const struct drm_prop_enum_list props[] = {
                { DRM_ROTATE_0,   "rotate-0" },
                { DRM_ROTATE_90,  "rotate-90" },
                { DRM_ROTATE_180, "rotate-180" },
                { DRM_ROTATE_270, "rotate-270" },
                { DRM_REFLECT_X,  "reflect-x" },
                { DRM_REFLECT_Y,  "reflect-y" },
        };

        return drm_property_create_bitmask(dev, 0, "rotation",
                                           props, ARRAY_SIZE(props),
                                           supported_rotations);
}
EXPORT_SYMBOL(drm_mode_create_rotation_property);

/**
 * DOC: Tile group
 *
 * Tile groups are used to represent tiled monitors with a unique
 * integer identifier. Tiled monitors using DisplayID v1.3 have
 * a unique 8-byte handle, we store this in a tile group, so we
 * have a common identifier for all tiles in a monitor group.
 */
static void drm_tile_group_free(struct kref *kref)
{
        struct drm_tile_group *tg = container_of(kref, struct drm_tile_group, refcount);
        struct drm_device *dev = tg->dev;
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_remove(&dev->mode_config.tile_idr, tg->id);
        mutex_unlock(&dev->mode_config.idr_mutex);
        kfree(tg);
}

/**
 * drm_mode_put_tile_group - drop a reference to a tile group.
 * @dev: DRM device
 * @tg: tile group to drop reference to.
 *
 * drop reference to tile group and free if 0.
 */
void drm_mode_put_tile_group(struct drm_device *dev,
                             struct drm_tile_group *tg)
{
        kref_put(&tg->refcount, drm_tile_group_free);
}

/**
 * drm_mode_get_tile_group - get a reference to an existing tile group
 * @dev: DRM device
 * @topology: 8-bytes unique per monitor.
 *
 * Use the unique bytes to get a reference to an existing tile group.
 *
 * RETURNS:
 * tile group or NULL if not found.
 */
struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
                                               char topology[8])
{
        struct drm_tile_group *tg;
        int id;
        mutex_lock(&dev->mode_config.idr_mutex);
        idr_for_each_entry(&dev->mode_config.tile_idr, tg, id) {
                if (!memcmp(tg->group_data, topology, 8)) {
                        if (!kref_get_unless_zero(&tg->refcount))
                                tg = NULL;
                        mutex_unlock(&dev->mode_config.idr_mutex);
                        return tg;
                }
        }
        mutex_unlock(&dev->mode_config.idr_mutex);
        return NULL;
}
EXPORT_SYMBOL(drm_mode_get_tile_group);

/**
 * drm_mode_create_tile_group - create a tile group from a displayid description
 * @dev: DRM device
 * @topology: 8-bytes unique per monitor.
 *
 * Create a tile group for the unique monitor, and get a unique
 * identifier for the tile group.
 *
 * RETURNS:
 * new tile group or error.
 */
struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
                                                  char topology[8])
{
        struct drm_tile_group *tg;
        int ret;

        tg = kzalloc(sizeof(*tg), GFP_KERNEL);
        if (!tg)
                return ERR_PTR(-ENOMEM);

        kref_init(&tg->refcount);
        memcpy(tg->group_data, topology, 8);
        tg->dev = dev;

        mutex_lock(&dev->mode_config.idr_mutex);
        ret = idr_alloc(&dev->mode_config.tile_idr, tg, 1, 0, GFP_KERNEL);
        if (ret >= 0) {
                tg->id = ret;
        } else {
                kfree(tg);
                tg = ERR_PTR(ret);
        }

        mutex_unlock(&dev->mode_config.idr_mutex);
        return tg;
}
EXPORT_SYMBOL(drm_mode_create_tile_group);