drivers/gpu/drm/drm_fb_helper.c

   1 /*
   2  * Copyright (c) 2006-2009 Red Hat Inc.
   3  * Copyright (c) 2006-2008 Intel Corporation
   4  * Copyright (c) 2007 Dave Airlie <airlied@linux.ie>
   5  *
   6  * DRM framebuffer helper functions
   7  *
   8  * Permission to use, copy, modify, distribute, and sell this software and its
   9  * documentation for any purpose is hereby granted without fee, provided that
  10  * the above copyright notice appear in all copies and that both that copyright
  11  * notice and this permission notice appear in supporting documentation, and
  12  * that the name of the copyright holders not be used in advertising or
  13  * publicity pertaining to distribution of the software without specific,
  14  * written prior permission.  The copyright holders make no representations
  15  * about the suitability of this software for any purpose.  It is provided "as
  16  * is" without express or implied warranty.
  17  *
  18  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  19  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  20  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  21  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  22  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  23  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  24  * OF THIS SOFTWARE.
  25  *
  26  * Authors:
  27  *      Dave Airlie <airlied@linux.ie>
  28  *      Jesse Barnes <jesse.barnes@intel.com>
  29  */
  30 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  31
  32 #include <linux/kernel.h>
  33 #include <linux/sysrq.h>
  34 #include <linux/slab.h>
  35 #include <linux/fb.h>
  36 #include <linux/module.h>
  37 #include <drm/drmP.h>
  38 #include <drm/drm_crtc.h>
  39 #include <drm/drm_fb_helper.h>
  40 #include <drm/drm_crtc_helper.h>
  41
  42 static LIST_HEAD(kernel_fb_helper_list);
  43
  44 /**
  45  * DOC: fbdev helpers
  46  *
  47  * The fb helper functions are useful to provide an fbdev on top of a drm kernel
  48  * mode setting driver. They can be used mostly independently from the crtc
  49  * helper functions used by many drivers to implement the kernel mode setting
  50  * interfaces.
  51  *
  52  * Initialization is done as a four-step process with drm_fb_helper_prepare(),
  53  * drm_fb_helper_init(), drm_fb_helper_single_add_all_connectors() and
  54  * drm_fb_helper_initial_config(). Drivers with fancier requirements than the
  55  * default behaviour can override the third step with their own code.
  56  * Teardown is done with drm_fb_helper_fini().
  57  *
  58  * At runtime drivers should restore the fbdev console by calling
  59  * drm_fb_helper_restore_fbdev_mode() from their ->lastclose callback. They
  60  * should also notify the fb helper code from updates to the output
  61  * configuration by calling drm_fb_helper_hotplug_event(). For easier
  62  * integration with the output polling code in drm_crtc_helper.c the modeset
  63  * code provides a ->output_poll_changed callback.
  64  *
  65  * All other functions exported by the fb helper library can be used to
  66  * implement the fbdev driver interface by the driver.
  67  *
  68  * It is possible, though perhaps somewhat tricky, to implement race-free
  69  * hotplug detection using the fbdev helpers. The drm_fb_helper_prepare()
  70  * helper must be called first to initialize the minimum required to make
  71  * hotplug detection work. Drivers also need to make sure to properly set up
  72  * the dev->mode_config.funcs member. After calling drm_kms_helper_poll_init()
  73  * it is safe to enable interrupts and start processing hotplug events. At the
  74  * same time, drivers should initialize all modeset objects such as CRTCs,
  75  * encoders and connectors. To finish up the fbdev helper initialization, the
  76  * drm_fb_helper_init() function is called. To probe for all attached displays
  77  * and set up an initial configuration using the detected hardware, drivers
  78  * should call drm_fb_helper_single_add_all_connectors() followed by
  79  * drm_fb_helper_initial_config().
  80  */
  81
  82 /**
  83  * drm_fb_helper_single_add_all_connectors() - add all connectors to fbdev
  84  *                                             emulation helper
  85  * @fb_helper: fbdev initialized with drm_fb_helper_init
  86  *
  87  * This functions adds all the available connectors for use with the given
  88  * fb_helper. This is a separate step to allow drivers to freely assign
  89  * connectors to the fbdev, e.g. if some are reserved for special purposes or
  90  * not adequate to be used for the fbcon.
  91  *
  92  * Since this is part of the initial setup before the fbdev is published, no
  93  * locking is required.
  94  */
  95 int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper)
  96 {
  97         struct drm_device *dev = fb_helper->dev;
  98         struct drm_connector *connector;
  99         int i;
 100
 101         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
 102                 struct drm_fb_helper_connector *fb_helper_connector;
 103
 104                 fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 105                 if (!fb_helper_connector)
 106                         goto fail;
 107
 108                 fb_helper_connector->connector = connector;
 109                 fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 110         }
 111         return 0;
 112 fail:
 113         for (i = 0; i < fb_helper->connector_count; i++) {
 114                 kfree(fb_helper->connector_info[i]);
 115                 fb_helper->connector_info[i] = NULL;
 116         }
 117         fb_helper->connector_count = 0;
 118         return -ENOMEM;
 119 }
 120 EXPORT_SYMBOL(drm_fb_helper_single_add_all_connectors);
 121
 122 int drm_fb_helper_add_one_connector(struct drm_fb_helper *fb_helper, struct drm_connector *connector)
 123 {
 124         struct drm_fb_helper_connector **temp;
 125         struct drm_fb_helper_connector *fb_helper_connector;
 126
 127         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 128         if (fb_helper->connector_count + 1 > fb_helper->connector_info_alloc_count) {
 129                 temp = krealloc(fb_helper->connector_info, sizeof(struct drm_fb_helper_connector *) * (fb_helper->connector_count + 1), GFP_KERNEL);
 130                 if (!temp)
 131                         return -ENOMEM;
 132
 133                 fb_helper->connector_info_alloc_count = fb_helper->connector_count + 1;
 134                 fb_helper->connector_info = temp;
 135         }
 136
 137
 138         fb_helper_connector = kzalloc(sizeof(struct drm_fb_helper_connector), GFP_KERNEL);
 139         if (!fb_helper_connector)
 140                 return -ENOMEM;
 141
 142         fb_helper_connector->connector = connector;
 143         fb_helper->connector_info[fb_helper->connector_count++] = fb_helper_connector;
 144         return 0;
 145 }
 146 EXPORT_SYMBOL(drm_fb_helper_add_one_connector);
 147
 148 int drm_fb_helper_remove_one_connector(struct drm_fb_helper *fb_helper,
 149                                        struct drm_connector *connector)
 150 {
 151         struct drm_fb_helper_connector *fb_helper_connector;
 152         int i, j;
 153
 154         WARN_ON(!mutex_is_locked(&fb_helper->dev->mode_config.mutex));
 155
 156         for (i = 0; i < fb_helper->connector_count; i++) {
 157                 if (fb_helper->connector_info[i]->connector == connector)
 158                         break;
 159         }
 160
 161         if (i == fb_helper->connector_count)
 162                 return -EINVAL;
 163         fb_helper_connector = fb_helper->connector_info[i];
 164
 165         for (j = i + 1; j < fb_helper->connector_count; j++) {
 166                 fb_helper->connector_info[j - 1] = fb_helper->connector_info[j];
 167         }
 168         fb_helper->connector_count--;
 169         kfree(fb_helper_connector);
 170         return 0;
 171 }
 172 EXPORT_SYMBOL(drm_fb_helper_remove_one_connector);
 173
 174 static void drm_fb_helper_save_lut_atomic(struct drm_crtc *crtc, struct drm_fb_helper *helper)
 175 {
 176         uint16_t *r_base, *g_base, *b_base;
 177         int i;
 178
 179         if (helper->funcs->gamma_get == NULL)
 180                 return;
 181
 182         r_base = crtc->gamma_store;
 183         g_base = r_base + crtc->gamma_size;
 184         b_base = g_base + crtc->gamma_size;
 185
 186         for (i = 0; i < crtc->gamma_size; i++)
 187                 helper->funcs->gamma_get(crtc, &r_base[i], &g_base[i], &b_base[i], i);
 188 }
 189
 190 static void drm_fb_helper_restore_lut_atomic(struct drm_crtc *crtc)
 191 {
 192         uint16_t *r_base, *g_base, *b_base;
 193
 194         if (crtc->funcs->gamma_set == NULL)
 195                 return;
 196
 197         r_base = crtc->gamma_store;
 198         g_base = r_base + crtc->gamma_size;
 199         b_base = g_base + crtc->gamma_size;
 200
 201         crtc->funcs->gamma_set(crtc, r_base, g_base, b_base, 0, crtc->gamma_size);
 202 }
 203
 204 /**
 205  * drm_fb_helper_debug_enter - implementation for ->fb_debug_enter
 206  * @info: fbdev registered by the helper
 207  */
 208 int drm_fb_helper_debug_enter(struct fb_info *info)
 209 {
 210         struct drm_fb_helper *helper = info->par;
 211         struct drm_crtc_helper_funcs *funcs;
 212         int i;
 213
 214         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 215                 for (i = 0; i < helper->crtc_count; i++) {
 216                         struct drm_mode_set *mode_set =
 217                                 &helper->crtc_info[i].mode_set;
 218
 219                         if (!mode_set->crtc->enabled)
 220                                 continue;
 221
 222                         funcs = mode_set->crtc->helper_private;
 223                         drm_fb_helper_save_lut_atomic(mode_set->crtc, helper);
 224                         funcs->mode_set_base_atomic(mode_set->crtc,
 225                                                     mode_set->fb,
 226                                                     mode_set->x,
 227                                                     mode_set->y,
 228                                                     ENTER_ATOMIC_MODE_SET);
 229                 }
 230         }
 231
 232         return 0;
 233 }
 234 EXPORT_SYMBOL(drm_fb_helper_debug_enter);
 235
 236 /* Find the real fb for a given fb helper CRTC */
 237 static struct drm_framebuffer *drm_mode_config_fb(struct drm_crtc *crtc)
 238 {
 239         struct drm_device *dev = crtc->dev;
 240         struct drm_crtc *c;
 241
 242         list_for_each_entry(c, &dev->mode_config.crtc_list, head) {
 243                 if (crtc->base.id == c->base.id)
 244                         return c->primary->fb;
 245         }
 246
 247         return NULL;
 248 }
 249
 250 /**
 251  * drm_fb_helper_debug_leave - implementation for ->fb_debug_leave
 252  * @info: fbdev registered by the helper
 253  */
 254 int drm_fb_helper_debug_leave(struct fb_info *info)
 255 {
 256         struct drm_fb_helper *helper = info->par;
 257         struct drm_crtc *crtc;
 258         struct drm_crtc_helper_funcs *funcs;
 259         struct drm_framebuffer *fb;
 260         int i;
 261
 262         for (i = 0; i < helper->crtc_count; i++) {
 263                 struct drm_mode_set *mode_set = &helper->crtc_info[i].mode_set;
 264                 crtc = mode_set->crtc;
 265                 funcs = crtc->helper_private;
 266                 fb = drm_mode_config_fb(crtc);
 267
 268                 if (!crtc->enabled)
 269                         continue;
 270
 271                 if (!fb) {
 272                         DRM_ERROR("no fb to restore??\n");
 273                         continue;
 274                 }
 275
 276                 drm_fb_helper_restore_lut_atomic(mode_set->crtc);
 277                 funcs->mode_set_base_atomic(mode_set->crtc, fb, crtc->x,
 278                                             crtc->y, LEAVE_ATOMIC_MODE_SET);
 279         }
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL(drm_fb_helper_debug_leave);
 284
 285 static bool restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 286 {
 287         struct drm_device *dev = fb_helper->dev;
 288         struct drm_plane *plane;
 289         bool error = false;
 290         int i;
 291
 292         drm_warn_on_modeset_not_all_locked(dev);
 293
 294         list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
 295                 if (plane->type != DRM_PLANE_TYPE_PRIMARY)
 296                         drm_plane_force_disable(plane);
 297
 298                 if (dev->mode_config.rotation_property) {
 299                         drm_mode_plane_set_obj_prop(plane,
 300                                                     dev->mode_config.rotation_property,
 301                                                     BIT(DRM_ROTATE_0));
 302                 }
 303         }
 304
 305         for (i = 0; i < fb_helper->crtc_count; i++) {
 306                 struct drm_mode_set *mode_set = &fb_helper->crtc_info[i].mode_set;
 307                 struct drm_crtc *crtc = mode_set->crtc;
 308                 int ret;
 309
 310                 if (crtc->funcs->cursor_set) {
 311                         ret = crtc->funcs->cursor_set(crtc, NULL, 0, 0, 0);
 312                         if (ret)
 313                                 error = true;
 314                 }
 315
 316                 ret = drm_mode_set_config_internal(mode_set);
 317                 if (ret)
 318                         error = true;
 319         }
 320         return error;
 321 }
 322 /**
 323  * drm_fb_helper_restore_fbdev_mode - restore fbdev configuration
 324  * @fb_helper: fbcon to restore
 325  *
 326  * This should be called from driver's drm ->lastclose callback
 327  * when implementing an fbcon on top of kms using this helper. This ensures that
 328  * the user isn't greeted with a black screen when e.g. X dies.
 329  *
 330  * Use this variant if you need to bypass locking (panic), or already
 331  * hold all modeset locks.  Otherwise use drm_fb_helper_restore_fbdev_mode_unlocked()
 332  */
 333 static bool drm_fb_helper_restore_fbdev_mode(struct drm_fb_helper *fb_helper)
 334 {
 335         return restore_fbdev_mode(fb_helper);
 336 }
 337
 338 /**
 339  * drm_fb_helper_restore_fbdev_mode_unlocked - restore fbdev configuration
 340  * @fb_helper: fbcon to restore
 341  *
 342  * This should be called from driver's drm ->lastclose callback
 343  * when implementing an fbcon on top of kms using this helper. This ensures that
 344  * the user isn't greeted with a black screen when e.g. X dies.
 345  */
 346 bool drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper)
 347 {
 348         struct drm_device *dev = fb_helper->dev;
 349         bool ret;
 350         bool do_delayed = false;
 351
 352         drm_modeset_lock_all(dev);
 353         ret = restore_fbdev_mode(fb_helper);
 354
 355         do_delayed = fb_helper->delayed_hotplug;
 356         if (do_delayed)
 357                 fb_helper->delayed_hotplug = false;
 358         drm_modeset_unlock_all(dev);
 359
 360         if (do_delayed)
 361                 drm_fb_helper_hotplug_event(fb_helper);
 362         return ret;
 363 }
 364 EXPORT_SYMBOL(drm_fb_helper_restore_fbdev_mode_unlocked);
 365
 366 /*
 367  * restore fbcon display for all kms driver's using this helper, used for sysrq
 368  * and panic handling.
 369  */
 370 static bool drm_fb_helper_force_kernel_mode(void)
 371 {
 372         bool ret, error = false;
 373         struct drm_fb_helper *helper;
 374
 375         if (list_empty(&kernel_fb_helper_list))
 376                 return false;
 377
 378         list_for_each_entry(helper, &kernel_fb_helper_list, kernel_fb_list) {
 379                 struct drm_device *dev = helper->dev;
 380
 381                 if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 382                         continue;
 383
 384                 /*
 385                  * NOTE: Use trylock mode to avoid deadlocks and sleeping in
 386                  * panic context.
 387                  */
 388                 if (__drm_modeset_lock_all(dev, true) != 0) {
 389                         error = true;
 390                         continue;
 391                 }
 392
 393                 ret = drm_fb_helper_restore_fbdev_mode(helper);
 394                 if (ret)
 395                         error = true;
 396
 397                 drm_modeset_unlock_all(dev);
 398         }
 399         return error;
 400 }
 401
 402 static int drm_fb_helper_panic(struct notifier_block *n, unsigned long ununsed,
 403                         void *panic_str)
 404 {
 405         /*
 406          * It's a waste of time and effort to switch back to text console
 407          * if the kernel should reboot before panic messages can be seen.
 408          */
 409         if (panic_timeout < 0)
 410                 return 0;
 411
 412         pr_err("panic occurred, switching back to text console\n");
 413         return drm_fb_helper_force_kernel_mode();
 414 }
 415
 416 static struct notifier_block paniced = {
 417         .notifier_call = drm_fb_helper_panic,
 418 };
 419
 420 static bool drm_fb_helper_is_bound(struct drm_fb_helper *fb_helper)
 421 {
 422         struct drm_device *dev = fb_helper->dev;
 423         struct drm_crtc *crtc;
 424         int bound = 0, crtcs_bound = 0;
 425
 426         /* Sometimes user space wants everything disabled, so don't steal the
 427          * display if there's a master. */
 428         if (dev->primary->master)
 429                 return false;
 430
 431         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 432                 if (crtc->primary->fb)
 433                         crtcs_bound++;
 434                 if (crtc->primary->fb == fb_helper->fb)
 435                         bound++;
 436         }
 437
 438         if (bound < crtcs_bound)
 439                 return false;
 440
 441         return true;
 442 }
 443
 444 #ifdef CONFIG_MAGIC_SYSRQ
 445 static void drm_fb_helper_restore_work_fn(struct work_struct *ignored)
 446 {
 447         bool ret;
 448         ret = drm_fb_helper_force_kernel_mode();
 449         if (ret == true)
 450                 DRM_ERROR("Failed to restore crtc configuration\n");
 451 }
 452 static DECLARE_WORK(drm_fb_helper_restore_work, drm_fb_helper_restore_work_fn);
 453
 454 static void drm_fb_helper_sysrq(int dummy1)
 455 {
 456         schedule_work(&drm_fb_helper_restore_work);
 457 }
 458
 459 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = {
 460         .handler = drm_fb_helper_sysrq,
 461         .help_msg = "force-fb(V)",
 462         .action_msg = "Restore framebuffer console",
 463 };
 464 #else
 465 static struct sysrq_key_op sysrq_drm_fb_helper_restore_op = { };
 466 #endif
 467
 468 static void drm_fb_helper_dpms(struct fb_info *info, int dpms_mode)
 469 {
 470         struct drm_fb_helper *fb_helper = info->par;
 471         struct drm_device *dev = fb_helper->dev;
 472         struct drm_crtc *crtc;
 473         struct drm_connector *connector;
 474         int i, j;
 475
 476         /*
 477          * fbdev->blank can be called from irq context in case of a panic.
 478          * Since we already have our own special panic handler which will
 479          * restore the fbdev console mode completely, just bail out early.
 480          */
 481         if (oops_in_progress)
 482                 return;
 483
 484         /*
 485          * For each CRTC in this fb, turn the connectors on/off.
 486          */
 487         drm_modeset_lock_all(dev);
 488         if (!drm_fb_helper_is_bound(fb_helper)) {
 489                 drm_modeset_unlock_all(dev);
 490                 return;
 491         }
 492
 493         for (i = 0; i < fb_helper->crtc_count; i++) {
 494                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 495
 496                 if (!crtc->enabled)
 497                         continue;
 498
 499                 /* Walk the connectors & encoders on this fb turning them on/off */
 500                 for (j = 0; j < fb_helper->connector_count; j++) {
 501                         connector = fb_helper->connector_info[j]->connector;
 502                         connector->funcs->dpms(connector, dpms_mode);
 503                         drm_object_property_set_value(&connector->base,
 504                                 dev->mode_config.dpms_property, dpms_mode);
 505                 }
 506         }
 507         drm_modeset_unlock_all(dev);
 508 }
 509
 510 /**
 511  * drm_fb_helper_blank - implementation for ->fb_blank
 512  * @blank: desired blanking state
 513  * @info: fbdev registered by the helper
 514  */
 515 int drm_fb_helper_blank(int blank, struct fb_info *info)
 516 {
 517         switch (blank) {
 518         /* Display: On; HSync: On, VSync: On */
 519         case FB_BLANK_UNBLANK:
 520                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_ON);
 521                 break;
 522         /* Display: Off; HSync: On, VSync: On */
 523         case FB_BLANK_NORMAL:
 524                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 525                 break;
 526         /* Display: Off; HSync: Off, VSync: On */
 527         case FB_BLANK_HSYNC_SUSPEND:
 528                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_STANDBY);
 529                 break;
 530         /* Display: Off; HSync: On, VSync: Off */
 531         case FB_BLANK_VSYNC_SUSPEND:
 532                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_SUSPEND);
 533                 break;
 534         /* Display: Off; HSync: Off, VSync: Off */
 535         case FB_BLANK_POWERDOWN:
 536                 drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF);
 537                 break;
 538         }
 539         return 0;
 540 }
 541 EXPORT_SYMBOL(drm_fb_helper_blank);
 542
 543 static void drm_fb_helper_crtc_free(struct drm_fb_helper *helper)
 544 {
 545         int i;
 546
 547         for (i = 0; i < helper->connector_count; i++)
 548                 kfree(helper->connector_info[i]);
 549         kfree(helper->connector_info);
 550         for (i = 0; i < helper->crtc_count; i++) {
 551                 kfree(helper->crtc_info[i].mode_set.connectors);
 552                 if (helper->crtc_info[i].mode_set.mode)
 553                         drm_mode_destroy(helper->dev, helper->crtc_info[i].mode_set.mode);
 554         }
 555         kfree(helper->crtc_info);
 556 }
 557
 558 /**
 559  * drm_fb_helper_prepare - setup a drm_fb_helper structure
 560  * @dev: DRM device
 561  * @helper: driver-allocated fbdev helper structure to set up
 562  * @funcs: pointer to structure of functions associate with this helper
 563  *
 564  * Sets up the bare minimum to make the framebuffer helper usable. This is
 565  * useful to implement race-free initialization of the polling helpers.
 566  */
 567 void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper,
 568                            const struct drm_fb_helper_funcs *funcs)
 569 {
 570         INIT_LIST_HEAD(&helper->kernel_fb_list);
 571         helper->funcs = funcs;
 572         helper->dev = dev;
 573 }
 574 EXPORT_SYMBOL(drm_fb_helper_prepare);
 575
 576 /**
 577  * drm_fb_helper_init - initialize a drm_fb_helper structure
 578  * @dev: drm device
 579  * @fb_helper: driver-allocated fbdev helper structure to initialize
 580  * @crtc_count: maximum number of crtcs to support in this fbdev emulation
 581  * @max_conn_count: max connector count
 582  *
 583  * This allocates the structures for the fbdev helper with the given limits.
 584  * Note that this won't yet touch the hardware (through the driver interfaces)
 585  * nor register the fbdev. This is only done in drm_fb_helper_initial_config()
 586  * to allow driver writes more control over the exact init sequence.
 587  *
 588  * Drivers must call drm_fb_helper_prepare() before calling this function.
 589  *
 590  * RETURNS:
 591  * Zero if everything went ok, nonzero otherwise.
 592  */
 593 int drm_fb_helper_init(struct drm_device *dev,
 594                        struct drm_fb_helper *fb_helper,
 595                        int crtc_count, int max_conn_count)
 596 {
 597         struct drm_crtc *crtc;
 598         int i;
 599
 600         if (!max_conn_count)
 601                 return -EINVAL;
 602
 603         fb_helper->crtc_info = kcalloc(crtc_count, sizeof(struct drm_fb_helper_crtc), GFP_KERNEL);
 604         if (!fb_helper->crtc_info)
 605                 return -ENOMEM;
 606
 607         fb_helper->crtc_count = crtc_count;
 608         fb_helper->connector_info = kcalloc(dev->mode_config.num_connector, sizeof(struct drm_fb_helper_connector *), GFP_KERNEL);
 609         if (!fb_helper->connector_info) {
 610                 kfree(fb_helper->crtc_info);
 611                 return -ENOMEM;
 612         }
 613         fb_helper->connector_info_alloc_count = dev->mode_config.num_connector;
 614         fb_helper->connector_count = 0;
 615
 616         for (i = 0; i < crtc_count; i++) {
 617                 fb_helper->crtc_info[i].mode_set.connectors =
 618                         kcalloc(max_conn_count,
 619                                 sizeof(struct drm_connector *),
 620                                 GFP_KERNEL);
 621
 622                 if (!fb_helper->crtc_info[i].mode_set.connectors)
 623                         goto out_free;
 624                 fb_helper->crtc_info[i].mode_set.num_connectors = 0;
 625         }
 626
 627         i = 0;
 628         list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 629                 fb_helper->crtc_info[i].mode_set.crtc = crtc;
 630                 i++;
 631         }
 632
 633         return 0;
 634 out_free:
 635         drm_fb_helper_crtc_free(fb_helper);
 636         return -ENOMEM;
 637 }
 638 EXPORT_SYMBOL(drm_fb_helper_init);
 639
 640 void drm_fb_helper_fini(struct drm_fb_helper *fb_helper)
 641 {
 642         if (!list_empty(&fb_helper->kernel_fb_list)) {
 643                 list_del(&fb_helper->kernel_fb_list);
 644                 if (list_empty(&kernel_fb_helper_list)) {
 645                         pr_info("drm: unregistered panic notifier\n");
 646                         atomic_notifier_chain_unregister(&panic_notifier_list,
 647                                                          &paniced);
 648                         unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 649                 }
 650         }
 651
 652         drm_fb_helper_crtc_free(fb_helper);
 653
 654 }
 655 EXPORT_SYMBOL(drm_fb_helper_fini);
 656
 657 static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green,
 658                      u16 blue, u16 regno, struct fb_info *info)
 659 {
 660         struct drm_fb_helper *fb_helper = info->par;
 661         struct drm_framebuffer *fb = fb_helper->fb;
 662         int pindex;
 663
 664         if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
 665                 u32 *palette;
 666                 u32 value;
 667                 /* place color in psuedopalette */
 668                 if (regno > 16)
 669                         return -EINVAL;
 670                 palette = (u32 *)info->pseudo_palette;
 671                 red >>= (16 - info->var.red.length);
 672                 green >>= (16 - info->var.green.length);
 673                 blue >>= (16 - info->var.blue.length);
 674                 value = (red << info->var.red.offset) |
 675                         (green << info->var.green.offset) |
 676                         (blue << info->var.blue.offset);
 677                 if (info->var.transp.length > 0) {
 678                         u32 mask = (1 << info->var.transp.length) - 1;
 679                         mask <<= info->var.transp.offset;
 680                         value |= mask;
 681                 }
 682                 palette[regno] = value;
 683                 return 0;
 684         }
 685
 686         /*
 687          * The driver really shouldn't advertise pseudo/directcolor
 688          * visuals if it can't deal with the palette.
 689          */
 690         if (WARN_ON(!fb_helper->funcs->gamma_set ||
 691                     !fb_helper->funcs->gamma_get))
 692                 return -EINVAL;
 693
 694         pindex = regno;
 695
 696         if (fb->bits_per_pixel == 16) {
 697                 pindex = regno << 3;
 698
 699                 if (fb->depth == 16 && regno > 63)
 700                         return -EINVAL;
 701                 if (fb->depth == 15 && regno > 31)
 702                         return -EINVAL;
 703
 704                 if (fb->depth == 16) {
 705                         u16 r, g, b;
 706                         int i;
 707                         if (regno < 32) {
 708                                 for (i = 0; i < 8; i++)
 709                                         fb_helper->funcs->gamma_set(crtc, red,
 710                                                 green, blue, pindex + i);
 711                         }
 712
 713                         fb_helper->funcs->gamma_get(crtc, &r,
 714                                                     &g, &b,
 715                                                     pindex >> 1);
 716
 717                         for (i = 0; i < 4; i++)
 718                                 fb_helper->funcs->gamma_set(crtc, r,
 719                                                             green, b,
 720                                                             (pindex >> 1) + i);
 721                 }
 722         }
 723
 724         if (fb->depth != 16)
 725                 fb_helper->funcs->gamma_set(crtc, red, green, blue, pindex);
 726         return 0;
 727 }
 728
 729 /**
 730  * drm_fb_helper_setcmap - implementation for ->fb_setcmap
 731  * @cmap: cmap to set
 732  * @info: fbdev registered by the helper
 733  */
 734 int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
 735 {
 736         struct drm_fb_helper *fb_helper = info->par;
 737         struct drm_device *dev = fb_helper->dev;
 738         struct drm_crtc_helper_funcs *crtc_funcs;
 739         u16 *red, *green, *blue, *transp;
 740         struct drm_crtc *crtc;
 741         int i, j, rc = 0;
 742         int start;
 743
 744         drm_modeset_lock_all(dev);
 745         if (!drm_fb_helper_is_bound(fb_helper)) {
 746                 drm_modeset_unlock_all(dev);
 747                 return -EBUSY;
 748         }
 749
 750         for (i = 0; i < fb_helper->crtc_count; i++) {
 751                 crtc = fb_helper->crtc_info[i].mode_set.crtc;
 752                 crtc_funcs = crtc->helper_private;
 753
 754                 red = cmap->red;
 755                 green = cmap->green;
 756                 blue = cmap->blue;
 757                 transp = cmap->transp;
 758                 start = cmap->start;
 759
 760                 for (j = 0; j < cmap->len; j++) {
 761                         u16 hred, hgreen, hblue, htransp = 0xffff;
 762
 763                         hred = *red++;
 764                         hgreen = *green++;
 765                         hblue = *blue++;
 766
 767                         if (transp)
 768                                 htransp = *transp++;
 769
 770                         rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
 771                         if (rc)
 772                                 goto out;
 773                 }
 774                 if (crtc_funcs->load_lut)
 775                         crtc_funcs->load_lut(crtc);
 776         }
 777  out:
 778         drm_modeset_unlock_all(dev);
 779         return rc;
 780 }
 781 EXPORT_SYMBOL(drm_fb_helper_setcmap);
 782
 783 /**
 784  * drm_fb_helper_check_var - implementation for ->fb_check_var
 785  * @var: screeninfo to check
 786  * @info: fbdev registered by the helper
 787  */
 788 int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
 789                             struct fb_info *info)
 790 {
 791         struct drm_fb_helper *fb_helper = info->par;
 792         struct drm_framebuffer *fb = fb_helper->fb;
 793         int depth;
 794
 795         if (var->pixclock != 0 || in_dbg_master())
 796                 return -EINVAL;
 797
 798         /* Need to resize the fb object !!! */
 799         if (var->bits_per_pixel > fb->bits_per_pixel ||
 800             var->xres > fb->width || var->yres > fb->height ||
 801             var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
 802                 DRM_DEBUG("fb userspace requested width/height/bpp is greater than current fb "
 803                           "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
 804                           var->xres, var->yres, var->bits_per_pixel,
 805                           var->xres_virtual, var->yres_virtual,
 806                           fb->width, fb->height, fb->bits_per_pixel);
 807                 return -EINVAL;
 808         }
 809
 810         switch (var->bits_per_pixel) {
 811         case 16:
 812                 depth = (var->green.length == 6) ? 16 : 15;
 813                 break;
 814         case 32:
 815                 depth = (var->transp.length > 0) ? 32 : 24;
 816                 break;
 817         default:
 818                 depth = var->bits_per_pixel;
 819                 break;
 820         }
 821
 822         switch (depth) {
 823         case 8:
 824                 var->red.offset = 0;
 825                 var->green.offset = 0;
 826                 var->blue.offset = 0;
 827                 var->red.length = 8;
 828                 var->green.length = 8;
 829                 var->blue.length = 8;
 830                 var->transp.length = 0;
 831                 var->transp.offset = 0;
 832                 break;
 833         case 15:
 834                 var->red.offset = 10;
 835                 var->green.offset = 5;
 836                 var->blue.offset = 0;
 837                 var->red.length = 5;
 838                 var->green.length = 5;
 839                 var->blue.length = 5;
 840                 var->transp.length = 1;
 841                 var->transp.offset = 15;
 842                 break;
 843         case 16:
 844                 var->red.offset = 11;
 845                 var->green.offset = 5;
 846                 var->blue.offset = 0;
 847                 var->red.length = 5;
 848                 var->green.length = 6;
 849                 var->blue.length = 5;
 850                 var->transp.length = 0;
 851                 var->transp.offset = 0;
 852                 break;
 853         case 24:
 854                 var->red.offset = 16;
 855                 var->green.offset = 8;
 856                 var->blue.offset = 0;
 857                 var->red.length = 8;
 858                 var->green.length = 8;
 859                 var->blue.length = 8;
 860                 var->transp.length = 0;
 861                 var->transp.offset = 0;
 862                 break;
 863         case 32:
 864                 var->red.offset = 16;
 865                 var->green.offset = 8;
 866                 var->blue.offset = 0;
 867                 var->red.length = 8;
 868                 var->green.length = 8;
 869                 var->blue.length = 8;
 870                 var->transp.length = 8;
 871                 var->transp.offset = 24;
 872                 break;
 873         default:
 874                 return -EINVAL;
 875         }
 876         return 0;
 877 }
 878 EXPORT_SYMBOL(drm_fb_helper_check_var);
 879
 880 /**
 881  * drm_fb_helper_set_par - implementation for ->fb_set_par
 882  * @info: fbdev registered by the helper
 883  *
 884  * This will let fbcon do the mode init and is called at initialization time by
 885  * the fbdev core when registering the driver, and later on through the hotplug
 886  * callback.
 887  */
 888 int drm_fb_helper_set_par(struct fb_info *info)
 889 {
 890         struct drm_fb_helper *fb_helper = info->par;
 891         struct fb_var_screeninfo *var = &info->var;
 892
 893         if (var->pixclock != 0) {
 894                 DRM_ERROR("PIXEL CLOCK SET\n");
 895                 return -EINVAL;
 896         }
 897
 898         drm_fb_helper_restore_fbdev_mode_unlocked(fb_helper);
 899
 900         return 0;
 901 }
 902 EXPORT_SYMBOL(drm_fb_helper_set_par);
 903
 904 /**
 905  * drm_fb_helper_pan_display - implementation for ->fb_pan_display
 906  * @var: updated screen information
 907  * @info: fbdev registered by the helper
 908  */
 909 int drm_fb_helper_pan_display(struct fb_var_screeninfo *var,
 910                               struct fb_info *info)
 911 {
 912         struct drm_fb_helper *fb_helper = info->par;
 913         struct drm_device *dev = fb_helper->dev;
 914         struct drm_mode_set *modeset;
 915         int ret = 0;
 916         int i;
 917
 918         drm_modeset_lock_all(dev);
 919         if (!drm_fb_helper_is_bound(fb_helper)) {
 920                 drm_modeset_unlock_all(dev);
 921                 return -EBUSY;
 922         }
 923
 924         for (i = 0; i < fb_helper->crtc_count; i++) {
 925                 modeset = &fb_helper->crtc_info[i].mode_set;
 926
 927                 modeset->x = var->xoffset;
 928                 modeset->y = var->yoffset;
 929
 930                 if (modeset->num_connectors) {
 931                         ret = drm_mode_set_config_internal(modeset);
 932                         if (!ret) {
 933                                 info->var.xoffset = var->xoffset;
 934                                 info->var.yoffset = var->yoffset;
 935                         }
 936                 }
 937         }
 938         drm_modeset_unlock_all(dev);
 939         return ret;
 940 }
 941 EXPORT_SYMBOL(drm_fb_helper_pan_display);
 942
 943 /*
 944  * Allocates the backing storage and sets up the fbdev info structure through
 945  * the ->fb_probe callback and then registers the fbdev and sets up the panic
 946  * notifier.
 947  */
 948 static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
 949                                          int preferred_bpp)
 950 {
 951         int ret = 0;
 952         int crtc_count = 0;
 953         int i;
 954         struct fb_info *info;
 955         struct drm_fb_helper_surface_size sizes;
 956         int gamma_size = 0;
 957
 958         memset(&sizes, 0, sizeof(struct drm_fb_helper_surface_size));
 959         sizes.surface_depth = 24;
 960         sizes.surface_bpp = 32;
 961         sizes.fb_width = (unsigned)-1;
 962         sizes.fb_height = (unsigned)-1;
 963
 964         /* if driver picks 8 or 16 by default use that
 965            for both depth/bpp */
 966         if (preferred_bpp != sizes.surface_bpp)
 967                 sizes.surface_depth = sizes.surface_bpp = preferred_bpp;
 968
 969         /* first up get a count of crtcs now in use and new min/maxes width/heights */
 970         for (i = 0; i < fb_helper->connector_count; i++) {
 971                 struct drm_fb_helper_connector *fb_helper_conn = fb_helper->connector_info[i];
 972                 struct drm_cmdline_mode *cmdline_mode;
 973
 974                 cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
 975
 976                 if (cmdline_mode->bpp_specified) {
 977                         switch (cmdline_mode->bpp) {
 978                         case 8:
 979                                 sizes.surface_depth = sizes.surface_bpp = 8;
 980                                 break;
 981                         case 15:
 982                                 sizes.surface_depth = 15;
 983                                 sizes.surface_bpp = 16;
 984                                 break;
 985                         case 16:
 986                                 sizes.surface_depth = sizes.surface_bpp = 16;
 987                                 break;
 988                         case 24:
 989                                 sizes.surface_depth = sizes.surface_bpp = 24;
 990                                 break;
 991                         case 32:
 992                                 sizes.surface_depth = 24;
 993                                 sizes.surface_bpp = 32;
 994                                 break;
 995                         }
 996                         break;
 997                 }
 998         }
 999
1000         crtc_count = 0;
1001         for (i = 0; i < fb_helper->crtc_count; i++) {
1002                 struct drm_display_mode *desired_mode;
1003                 desired_mode = fb_helper->crtc_info[i].desired_mode;
1004
1005                 if (desired_mode) {
1006                         if (gamma_size == 0)
1007                                 gamma_size = fb_helper->crtc_info[i].mode_set.crtc->gamma_size;
1008                         if (desired_mode->hdisplay < sizes.fb_width)
1009                                 sizes.fb_width = desired_mode->hdisplay;
1010                         if (desired_mode->vdisplay < sizes.fb_height)
1011                                 sizes.fb_height = desired_mode->vdisplay;
1012                         if (desired_mode->hdisplay > sizes.surface_width)
1013                                 sizes.surface_width = desired_mode->hdisplay;
1014                         if (desired_mode->vdisplay > sizes.surface_height)
1015                                 sizes.surface_height = desired_mode->vdisplay;
1016                         crtc_count++;
1017                 }
1018         }
1019
1020         if (crtc_count == 0 || sizes.fb_width == -1 || sizes.fb_height == -1) {
1021                 /* hmm everyone went away - assume VGA cable just fell out
1022                    and will come back later. */
1023                 DRM_INFO("Cannot find any crtc or sizes - going 1024x768\n");
1024                 sizes.fb_width = sizes.surface_width = 1024;
1025                 sizes.fb_height = sizes.surface_height = 768;
1026         }
1027
1028         /* push down into drivers */
1029         ret = (*fb_helper->funcs->fb_probe)(fb_helper, &sizes);
1030         if (ret < 0)
1031                 return ret;
1032
1033         info = fb_helper->fbdev;
1034
1035         /*
1036          * Set the fb pointer - usually drm_setup_crtcs does this for hotplug
1037          * events, but at init time drm_setup_crtcs needs to be called before
1038          * the fb is allocated (since we need to figure out the desired size of
1039          * the fb before we can allocate it ...). Hence we need to fix things up
1040          * here again.
1041          */
1042         for (i = 0; i < fb_helper->crtc_count; i++)
1043                 if (fb_helper->crtc_info[i].mode_set.num_connectors)
1044                         fb_helper->crtc_info[i].mode_set.fb = fb_helper->fb;
1045
1046
1047         info->var.pixclock = 0;
1048         if (register_framebuffer(info) < 0)
1049                 return -EINVAL;
1050
1051         dev_info(fb_helper->dev->dev, "fb%d: %s frame buffer device\n",
1052                         info->node, info->fix.id);
1053
1054         /* Switch back to kernel console on panic */
1055         /* multi card linked list maybe */
1056         if (list_empty(&kernel_fb_helper_list)) {
1057                 dev_info(fb_helper->dev->dev, "registered panic notifier\n");
1058                 atomic_notifier_chain_register(&panic_notifier_list,
1059                                                &paniced);
1060                 register_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
1061         }
1062
1063         list_add(&fb_helper->kernel_fb_list, &kernel_fb_helper_list);
1064
1065         return 0;
1066 }
1067
1068 /**
1069  * drm_fb_helper_fill_fix - initializes fixed fbdev information
1070  * @info: fbdev registered by the helper
1071  * @pitch: desired pitch
1072  * @depth: desired depth
1073  *
1074  * Helper to fill in the fixed fbdev information useful for a non-accelerated
1075  * fbdev emulations. Drivers which support acceleration methods which impose
1076  * additional constraints need to set up their own limits.
1077  *
1078  * Drivers should call this (or their equivalent setup code) from their
1079  * ->fb_probe callback.
1080  */
1081 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
1082                             uint32_t depth)
1083 {
1084         info->fix.type = FB_TYPE_PACKED_PIXELS;
1085         info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
1086                 FB_VISUAL_TRUECOLOR;
1087         info->fix.mmio_start = 0;
1088         info->fix.mmio_len = 0;
1089         info->fix.type_aux = 0;
1090         info->fix.xpanstep = 1; /* doing it in hw */
1091         info->fix.ypanstep = 1; /* doing it in hw */
1092         info->fix.ywrapstep = 0;
1093         info->fix.accel = FB_ACCEL_NONE;
1094
1095         info->fix.line_length = pitch;
1096         return;
1097 }
1098 EXPORT_SYMBOL(drm_fb_helper_fill_fix);
1099
1100 /**
1101  * drm_fb_helper_fill_var - initalizes variable fbdev information
1102  * @info: fbdev instance to set up
1103  * @fb_helper: fb helper instance to use as template
1104  * @fb_width: desired fb width
1105  * @fb_height: desired fb height
1106  *
1107  * Sets up the variable fbdev metainformation from the given fb helper instance
1108  * and the drm framebuffer allocated in fb_helper->fb.
1109  *
1110  * Drivers should call this (or their equivalent setup code) from their
1111  * ->fb_probe callback after having allocated the fbdev backing
1112  * storage framebuffer.
1113  */
1114 void drm_fb_helper_fill_var(struct fb_info *info, struct drm_fb_helper *fb_helper,
1115                             uint32_t fb_width, uint32_t fb_height)
1116 {
1117         struct drm_framebuffer *fb = fb_helper->fb;
1118         info->pseudo_palette = fb_helper->pseudo_palette;
1119         info->var.xres_virtual = fb->width;
1120         info->var.yres_virtual = fb->height;
1121         info->var.bits_per_pixel = fb->bits_per_pixel;
1122         info->var.accel_flags = FB_ACCELF_TEXT;
1123         info->var.xoffset = 0;
1124         info->var.yoffset = 0;
1125         info->var.activate = FB_ACTIVATE_NOW;
1126         info->var.height = -1;
1127         info->var.width = -1;
1128
1129         switch (fb->depth) {
1130         case 8:
1131                 info->var.red.offset = 0;
1132                 info->var.green.offset = 0;
1133                 info->var.blue.offset = 0;
1134                 info->var.red.length = 8; /* 8bit DAC */
1135                 info->var.green.length = 8;
1136                 info->var.blue.length = 8;
1137                 info->var.transp.offset = 0;
1138                 info->var.transp.length = 0;
1139                 break;
1140         case 15:
1141                 info->var.red.offset = 10;
1142                 info->var.green.offset = 5;
1143                 info->var.blue.offset = 0;
1144                 info->var.red.length = 5;
1145                 info->var.green.length = 5;
1146                 info->var.blue.length = 5;
1147                 info->var.transp.offset = 15;
1148                 info->var.transp.length = 1;
1149                 break;
1150         case 16:
1151                 info->var.red.offset = 11;
1152                 info->var.green.offset = 5;
1153                 info->var.blue.offset = 0;
1154                 info->var.red.length = 5;
1155                 info->var.green.length = 6;
1156                 info->var.blue.length = 5;
1157                 info->var.transp.offset = 0;
1158                 break;
1159         case 24:
1160                 info->var.red.offset = 16;
1161                 info->var.green.offset = 8;
1162                 info->var.blue.offset = 0;
1163                 info->var.red.length = 8;
1164                 info->var.green.length = 8;
1165                 info->var.blue.length = 8;
1166                 info->var.transp.offset = 0;
1167                 info->var.transp.length = 0;
1168                 break;
1169         case 32:
1170                 info->var.red.offset = 16;
1171                 info->var.green.offset = 8;
1172                 info->var.blue.offset = 0;
1173                 info->var.red.length = 8;
1174                 info->var.green.length = 8;
1175                 info->var.blue.length = 8;
1176                 info->var.transp.offset = 24;
1177                 info->var.transp.length = 8;
1178                 break;
1179         default:
1180                 break;
1181         }
1182
1183         info->var.xres = fb_width;
1184         info->var.yres = fb_height;
1185 }
1186 EXPORT_SYMBOL(drm_fb_helper_fill_var);
1187
1188 static int drm_fb_helper_probe_connector_modes(struct drm_fb_helper *fb_helper,
1189                                                uint32_t maxX,
1190                                                uint32_t maxY)
1191 {
1192         struct drm_connector *connector;
1193         int count = 0;
1194         int i;
1195
1196         for (i = 0; i < fb_helper->connector_count; i++) {
1197                 connector = fb_helper->connector_info[i]->connector;
1198                 count += connector->funcs->fill_modes(connector, maxX, maxY);
1199         }
1200
1201         return count;
1202 }
1203
1204 struct drm_display_mode *drm_has_preferred_mode(struct drm_fb_helper_connector *fb_connector, int width, int height)
1205 {
1206         struct drm_display_mode *mode;
1207
1208         list_for_each_entry(mode, &fb_connector->connector->modes, head) {
1209                 if (mode->hdisplay > width ||
1210                     mode->vdisplay > height)
1211                         continue;
1212                 if (mode->type & DRM_MODE_TYPE_PREFERRED)
1213                         return mode;
1214         }
1215         return NULL;
1216 }
1217 EXPORT_SYMBOL(drm_has_preferred_mode);
1218
1219 static bool drm_has_cmdline_mode(struct drm_fb_helper_connector *fb_connector)
1220 {
1221         return fb_connector->connector->cmdline_mode.specified;
1222 }
1223
1224 struct drm_display_mode *drm_pick_cmdline_mode(struct drm_fb_helper_connector *fb_helper_conn,
1225                                                       int width, int height)
1226 {
1227         struct drm_cmdline_mode *cmdline_mode;
1228         struct drm_display_mode *mode = NULL;
1229         bool prefer_non_interlace;
1230
1231         cmdline_mode = &fb_helper_conn->connector->cmdline_mode;
1232         if (cmdline_mode->specified == false)
1233                 return mode;
1234
1235         /* attempt to find a matching mode in the list of modes
1236          *  we have gotten so far, if not add a CVT mode that conforms
1237          */
1238         if (cmdline_mode->rb || cmdline_mode->margins)
1239                 goto create_mode;
1240
1241         prefer_non_interlace = !cmdline_mode->interlace;
1242  again:
1243         list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1244                 /* check width/height */
1245                 if (mode->hdisplay != cmdline_mode->xres ||
1246                     mode->vdisplay != cmdline_mode->yres)
1247                         continue;
1248
1249                 if (cmdline_mode->refresh_specified) {
1250                         if (mode->vrefresh != cmdline_mode->refresh)
1251                                 continue;
1252                 }
1253
1254                 if (cmdline_mode->interlace) {
1255                         if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
1256                                 continue;
1257                 } else if (prefer_non_interlace) {
1258                         if (mode->flags & DRM_MODE_FLAG_INTERLACE)
1259                                 continue;
1260                 }
1261                 return mode;
1262         }
1263
1264         if (prefer_non_interlace) {
1265                 prefer_non_interlace = false;
1266                 goto again;
1267         }
1268
1269 create_mode:
1270         mode = drm_mode_create_from_cmdline_mode(fb_helper_conn->connector->dev,
1271                                                  cmdline_mode);
1272         list_add(&mode->head, &fb_helper_conn->connector->modes);
1273         return mode;
1274 }
1275 EXPORT_SYMBOL(drm_pick_cmdline_mode);
1276
1277 static bool drm_connector_enabled(struct drm_connector *connector, bool strict)
1278 {
1279         bool enable;
1280
1281         if (strict)
1282                 enable = connector->status == connector_status_connected;
1283         else
1284                 enable = connector->status != connector_status_disconnected;
1285
1286         return enable;
1287 }
1288
1289 static void drm_enable_connectors(struct drm_fb_helper *fb_helper,
1290                                   bool *enabled)
1291 {
1292         bool any_enabled = false;
1293         struct drm_connector *connector;
1294         int i = 0;
1295
1296         for (i = 0; i < fb_helper->connector_count; i++) {
1297                 connector = fb_helper->connector_info[i]->connector;
1298                 enabled[i] = drm_connector_enabled(connector, true);
1299                 DRM_DEBUG_KMS("connector %d enabled? %s\n", connector->base.id,
1300                           enabled[i] ? "yes" : "no");
1301                 any_enabled |= enabled[i];
1302         }
1303
1304         if (any_enabled)
1305                 return;
1306
1307         for (i = 0; i < fb_helper->connector_count; i++) {
1308                 connector = fb_helper->connector_info[i]->connector;
1309                 enabled[i] = drm_connector_enabled(connector, false);
1310         }
1311 }
1312
1313 static bool drm_target_cloned(struct drm_fb_helper *fb_helper,
1314                               struct drm_display_mode **modes,
1315                               bool *enabled, int width, int height)
1316 {
1317         int count, i, j;
1318         bool can_clone = false;
1319         struct drm_fb_helper_connector *fb_helper_conn;
1320         struct drm_display_mode *dmt_mode, *mode;
1321
1322         /* only contemplate cloning in the single crtc case */
1323         if (fb_helper->crtc_count > 1)
1324                 return false;
1325
1326         count = 0;
1327         for (i = 0; i < fb_helper->connector_count; i++) {
1328                 if (enabled[i])
1329                         count++;
1330         }
1331
1332         /* only contemplate cloning if more than one connector is enabled */
1333         if (count <= 1)
1334                 return false;
1335
1336         /* check the command line or if nothing common pick 1024x768 */
1337         can_clone = true;
1338         for (i = 0; i < fb_helper->connector_count; i++) {
1339                 if (!enabled[i])
1340                         continue;
1341                 fb_helper_conn = fb_helper->connector_info[i];
1342                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1343                 if (!modes[i]) {
1344                         can_clone = false;
1345                         break;
1346                 }
1347                 for (j = 0; j < i; j++) {
1348                         if (!enabled[j])
1349                                 continue;
1350                         if (!drm_mode_equal(modes[j], modes[i]))
1351                                 can_clone = false;
1352                 }
1353         }
1354
1355         if (can_clone) {
1356                 DRM_DEBUG_KMS("can clone using command line\n");
1357                 return true;
1358         }
1359
1360         /* try and find a 1024x768 mode on each connector */
1361         can_clone = true;
1362         dmt_mode = drm_mode_find_dmt(fb_helper->dev, 1024, 768, 60, false);
1363
1364         for (i = 0; i < fb_helper->connector_count; i++) {
1365
1366                 if (!enabled[i])
1367                         continue;
1368
1369                 fb_helper_conn = fb_helper->connector_info[i];
1370                 list_for_each_entry(mode, &fb_helper_conn->connector->modes, head) {
1371                         if (drm_mode_equal(mode, dmt_mode))
1372                                 modes[i] = mode;
1373                 }
1374                 if (!modes[i])
1375                         can_clone = false;
1376         }
1377
1378         if (can_clone) {
1379                 DRM_DEBUG_KMS("can clone using 1024x768\n");
1380                 return true;
1381         }
1382         DRM_INFO("kms: can't enable cloning when we probably wanted to.\n");
1383         return false;
1384 }
1385
1386 static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
1387                                  struct drm_display_mode **modes,
1388                                  bool *enabled, int width, int height)
1389 {
1390         struct drm_fb_helper_connector *fb_helper_conn;
1391         int i;
1392
1393         for (i = 0; i < fb_helper->connector_count; i++) {
1394                 fb_helper_conn = fb_helper->connector_info[i];
1395
1396                 if (enabled[i] == false)
1397                         continue;
1398
1399                 DRM_DEBUG_KMS("looking for cmdline mode on connector %d\n",
1400                               fb_helper_conn->connector->base.id);
1401
1402                 /* got for command line mode first */
1403                 modes[i] = drm_pick_cmdline_mode(fb_helper_conn, width, height);
1404                 if (!modes[i]) {
1405                         DRM_DEBUG_KMS("looking for preferred mode on connector %d\n",
1406                                       fb_helper_conn->connector->base.id);
1407                         modes[i] = drm_has_preferred_mode(fb_helper_conn, width, height);
1408                 }
1409                 /* No preferred modes, pick one off the list */
1410                 if (!modes[i] && !list_empty(&fb_helper_conn->connector->modes)) {
1411                         list_for_each_entry(modes[i], &fb_helper_conn->connector->modes, head)
1412                                 break;
1413                 }
1414                 DRM_DEBUG_KMS("found mode %s\n", modes[i] ? modes[i]->name :
1415                           "none");
1416         }
1417         return true;
1418 }
1419
1420 static int drm_pick_crtcs(struct drm_fb_helper *fb_helper,
1421                           struct drm_fb_helper_crtc **best_crtcs,
1422                           struct drm_display_mode **modes,
1423                           int n, int width, int height)
1424 {
1425         int c, o;
1426         struct drm_device *dev = fb_helper->dev;
1427         struct drm_connector *connector;
1428         struct drm_connector_helper_funcs *connector_funcs;
1429         struct drm_encoder *encoder;
1430         int my_score, best_score, score;
1431         struct drm_fb_helper_crtc **crtcs, *crtc;
1432         struct drm_fb_helper_connector *fb_helper_conn;
1433
1434         if (n == fb_helper->connector_count)
1435                 return 0;
1436
1437         fb_helper_conn = fb_helper->connector_info[n];
1438         connector = fb_helper_conn->connector;
1439
1440         best_crtcs[n] = NULL;
1441         best_score = drm_pick_crtcs(fb_helper, best_crtcs, modes, n+1, width, height);
1442         if (modes[n] == NULL)
1443                 return best_score;
1444
1445         crtcs = kzalloc(dev->mode_config.num_connector *
1446                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1447         if (!crtcs)
1448                 return best_score;
1449
1450         my_score = 1;
1451         if (connector->status == connector_status_connected)
1452                 my_score++;
1453         if (drm_has_cmdline_mode(fb_helper_conn))
1454                 my_score++;
1455         if (drm_has_preferred_mode(fb_helper_conn, width, height))
1456                 my_score++;
1457
1458         connector_funcs = connector->helper_private;
1459         encoder = connector_funcs->best_encoder(connector);
1460         if (!encoder)
1461                 goto out;
1462
1463         /* select a crtc for this connector and then attempt to configure
1464            remaining connectors */
1465         for (c = 0; c < fb_helper->crtc_count; c++) {
1466                 crtc = &fb_helper->crtc_info[c];
1467
1468                 if ((encoder->possible_crtcs & (1 << c)) == 0)
1469                         continue;
1470
1471                 for (o = 0; o < n; o++)
1472                         if (best_crtcs[o] == crtc)
1473                                 break;
1474
1475                 if (o < n) {
1476                         /* ignore cloning unless only a single crtc */
1477                         if (fb_helper->crtc_count > 1)
1478                                 continue;
1479
1480                         if (!drm_mode_equal(modes[o], modes[n]))
1481                                 continue;
1482                 }
1483
1484                 crtcs[n] = crtc;
1485                 memcpy(crtcs, best_crtcs, n * sizeof(struct drm_fb_helper_crtc *));
1486                 score = my_score + drm_pick_crtcs(fb_helper, crtcs, modes, n + 1,
1487                                                   width, height);
1488                 if (score > best_score) {
1489                         best_score = score;
1490                         memcpy(best_crtcs, crtcs,
1491                                dev->mode_config.num_connector *
1492                                sizeof(struct drm_fb_helper_crtc *));
1493                 }
1494         }
1495 out:
1496         kfree(crtcs);
1497         return best_score;
1498 }
1499
1500 static void drm_setup_crtcs(struct drm_fb_helper *fb_helper)
1501 {
1502         struct drm_device *dev = fb_helper->dev;
1503         struct drm_fb_helper_crtc **crtcs;
1504         struct drm_display_mode **modes;
1505         struct drm_mode_set *modeset;
1506         bool *enabled;
1507         int width, height;
1508         int i;
1509
1510         DRM_DEBUG_KMS("\n");
1511
1512         width = dev->mode_config.max_width;
1513         height = dev->mode_config.max_height;
1514
1515         crtcs = kcalloc(dev->mode_config.num_connector,
1516                         sizeof(struct drm_fb_helper_crtc *), GFP_KERNEL);
1517         modes = kcalloc(dev->mode_config.num_connector,
1518                         sizeof(struct drm_display_mode *), GFP_KERNEL);
1519         enabled = kcalloc(dev->mode_config.num_connector,
1520                           sizeof(bool), GFP_KERNEL);
1521         if (!crtcs || !modes || !enabled) {
1522                 DRM_ERROR("Memory allocation failed\n");
1523                 goto out;
1524         }
1525
1526
1527         drm_enable_connectors(fb_helper, enabled);
1528
1529         if (!(fb_helper->funcs->initial_config &&
1530               fb_helper->funcs->initial_config(fb_helper, crtcs, modes,
1531                                                enabled, width, height))) {
1532                 memset(modes, 0, dev->mode_config.num_connector*sizeof(modes[0]));
1533                 memset(crtcs, 0, dev->mode_config.num_connector*sizeof(crtcs[0]));
1534
1535                 if (!drm_target_cloned(fb_helper,
1536                                        modes, enabled, width, height) &&
1537                     !drm_target_preferred(fb_helper,
1538                                           modes, enabled, width, height))
1539                         DRM_ERROR("Unable to find initial modes\n");
1540
1541                 DRM_DEBUG_KMS("picking CRTCs for %dx%d config\n",
1542                               width, height);
1543
1544                 drm_pick_crtcs(fb_helper, crtcs, modes, 0, width, height);
1545         }
1546
1547         /* need to set the modesets up here for use later */
1548         /* fill out the connector<->crtc mappings into the modesets */
1549         for (i = 0; i < fb_helper->crtc_count; i++) {
1550                 modeset = &fb_helper->crtc_info[i].mode_set;
1551                 modeset->num_connectors = 0;
1552                 modeset->fb = NULL;
1553         }
1554
1555         for (i = 0; i < fb_helper->connector_count; i++) {
1556                 struct drm_display_mode *mode = modes[i];
1557                 struct drm_fb_helper_crtc *fb_crtc = crtcs[i];
1558                 modeset = &fb_crtc->mode_set;
1559
1560                 if (mode && fb_crtc) {
1561                         DRM_DEBUG_KMS("desired mode %s set on crtc %d\n",
1562                                       mode->name, fb_crtc->mode_set.crtc->base.id);
1563                         fb_crtc->desired_mode = mode;
1564                         if (modeset->mode)
1565                                 drm_mode_destroy(dev, modeset->mode);
1566                         modeset->mode = drm_mode_duplicate(dev,
1567                                                            fb_crtc->desired_mode);
1568                         modeset->connectors[modeset->num_connectors++] = fb_helper->connector_info[i]->connector;
1569                         modeset->fb = fb_helper->fb;
1570                 }
1571         }
1572
1573         /* Clear out any old modes if there are no more connected outputs. */
1574         for (i = 0; i < fb_helper->crtc_count; i++) {
1575                 modeset = &fb_helper->crtc_info[i].mode_set;
1576                 if (modeset->num_connectors == 0) {
1577                         BUG_ON(modeset->fb);
1578                         if (modeset->mode)
1579                                 drm_mode_destroy(dev, modeset->mode);
1580                         modeset->mode = NULL;
1581                 }
1582         }
1583 out:
1584         kfree(crtcs);
1585         kfree(modes);
1586         kfree(enabled);
1587 }
1588
1589 /**
1590  * drm_fb_helper_initial_config - setup a sane initial connector configuration
1591  * @fb_helper: fb_helper device struct
1592  * @bpp_sel: bpp value to use for the framebuffer configuration
1593  *
1594  * Scans the CRTCs and connectors and tries to put together an initial setup.
1595  * At the moment, this is a cloned configuration across all heads with
1596  * a new framebuffer object as the backing store.
1597  *
1598  * Note that this also registers the fbdev and so allows userspace to call into
1599  * the driver through the fbdev interfaces.
1600  *
1601  * This function will call down into the ->fb_probe callback to let
1602  * the driver allocate and initialize the fbdev info structure and the drm
1603  * framebuffer used to back the fbdev. drm_fb_helper_fill_var() and
1604  * drm_fb_helper_fill_fix() are provided as helpers to setup simple default
1605  * values for the fbdev info structure.
1606  *
1607  * RETURNS:
1608  * Zero if everything went ok, nonzero otherwise.
1609  */
1610 bool drm_fb_helper_initial_config(struct drm_fb_helper *fb_helper, int bpp_sel)
1611 {
1612         struct drm_device *dev = fb_helper->dev;
1613         int count = 0;
1614
1615         mutex_lock(&dev->mode_config.mutex);
1616         count = drm_fb_helper_probe_connector_modes(fb_helper,
1617                                                     dev->mode_config.max_width,
1618                                                     dev->mode_config.max_height);
1619         mutex_unlock(&dev->mode_config.mutex);
1620         /*
1621          * we shouldn't end up with no modes here.
1622          */
1623         if (count == 0)
1624                 dev_info(fb_helper->dev->dev, "No connectors reported connected with modes\n");
1625
1626         drm_setup_crtcs(fb_helper);
1627
1628         return drm_fb_helper_single_fb_probe(fb_helper, bpp_sel);
1629 }
1630 EXPORT_SYMBOL(drm_fb_helper_initial_config);
1631
1632 /**
1633  * drm_fb_helper_hotplug_event - respond to a hotplug notification by
1634  *                               probing all the outputs attached to the fb
1635  * @fb_helper: the drm_fb_helper
1636  *
1637  * Scan the connectors attached to the fb_helper and try to put together a
1638  * setup after *notification of a change in output configuration.
1639  *
1640  * Called at runtime, takes the mode config locks to be able to check/change the
1641  * modeset configuration. Must be run from process context (which usually means
1642  * either the output polling work or a work item launched from the driver's
1643  * hotplug interrupt).
1644  *
1645  * Note that drivers may call this even before calling
1646  * drm_fb_helper_initial_config but only aftert drm_fb_helper_init. This allows
1647  * for a race-free fbcon setup and will make sure that the fbdev emulation will
1648  * not miss any hotplug events.
1649  *
1650  * RETURNS:
1651  * 0 on success and a non-zero error code otherwise.
1652  */
1653 int drm_fb_helper_hotplug_event(struct drm_fb_helper *fb_helper)
1654 {
1655         struct drm_device *dev = fb_helper->dev;
1656         u32 max_width, max_height;
1657
1658         mutex_lock(&fb_helper->dev->mode_config.mutex);
1659         if (!fb_helper->fb || !drm_fb_helper_is_bound(fb_helper)) {
1660                 fb_helper->delayed_hotplug = true;
1661                 mutex_unlock(&fb_helper->dev->mode_config.mutex);
1662                 return 0;
1663         }
1664         DRM_DEBUG_KMS("\n");
1665
1666         max_width = fb_helper->fb->width;
1667         max_height = fb_helper->fb->height;
1668
1669         drm_fb_helper_probe_connector_modes(fb_helper, max_width, max_height);
1670         mutex_unlock(&fb_helper->dev->mode_config.mutex);
1671
1672         drm_modeset_lock_all(dev);
1673         drm_setup_crtcs(fb_helper);
1674         drm_modeset_unlock_all(dev);
1675         drm_fb_helper_set_par(fb_helper->fbdev);
1676
1677         return 0;
1678 }
1679 EXPORT_SYMBOL(drm_fb_helper_hotplug_event);
1680
1681 /* The Kconfig DRM_KMS_HELPER selects FRAMEBUFFER_CONSOLE (if !EXPERT)
1682  * but the module doesn't depend on any fb console symbols.  At least
1683  * attempt to load fbcon to avoid leaving the system without a usable console.
1684  */
1685 #if defined(CONFIG_FRAMEBUFFER_CONSOLE_MODULE) && !defined(CONFIG_EXPERT)
1686 static int __init drm_fb_helper_modinit(void)
1687 {
1688         const char *name = "fbcon";
1689         struct module *fbcon;
1690
1691         mutex_lock(&module_mutex);
1692         fbcon = find_module(name);
1693         mutex_unlock(&module_mutex);
1694
1695         if (!fbcon)
1696                 request_module_nowait(name);
1697         return 0;
1698 }
1699
1700 module_init(drm_fb_helper_modinit);
1701 #endif