drivers/usb/gadget/uvc_v4l2.c

   1 /*
   2  *      uvc_v4l2.c  --  USB Video Class Gadget driver
   3  *
   4  *      Copyright (C) 2009-2010
   5  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   6  *
   7  *      This program is free software; you can redistribute it and/or modify
   8  *      it under the terms of the GNU General Public License as published by
   9  *      the Free Software Foundation; either version 2 of the License, or
  10  *      (at your option) any later version.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/device.h>
  15 #include <linux/errno.h>
  16 #include <linux/list.h>
  17 #include <linux/mutex.h>
  18 #include <linux/videodev2.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/wait.h>
  21
  22 #include <media/v4l2-dev.h>
  23 #include <media/v4l2-event.h>
  24 #include <media/v4l2-ioctl.h>
  25
  26 #include "uvc.h"
  27 #include "uvc_queue.h"
  28
  29 /* --------------------------------------------------------------------------
  30  * Requests handling
  31  */
  32
  33 static int
  34 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
  35 {
  36         struct usb_composite_dev *cdev = uvc->func.config->cdev;
  37         struct usb_request *req = uvc->control_req;
  38
  39         if (data->length < 0)
  40                 return usb_ep_set_halt(cdev->gadget->ep0);
  41
  42         req->length = min_t(unsigned int, uvc->event_length, data->length);
  43         req->zero = data->length < uvc->event_length;
  44
  45         memcpy(req->buf, data->data, req->length);
  46
  47         return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
  48 }
  49
  50 /* --------------------------------------------------------------------------
  51  * V4L2
  52  */
  53
  54 struct uvc_format
  55 {
  56         u8 bpp;
  57         u32 fcc;
  58 };
  59
  60 static struct uvc_format uvc_formats[] = {
  61         { 16, V4L2_PIX_FMT_YUYV  },
  62         { 0,  V4L2_PIX_FMT_MJPEG },
  63 };
  64
  65 static int
  66 uvc_v4l2_get_format(struct uvc_video *video, struct v4l2_format *fmt)
  67 {
  68         fmt->fmt.pix.pixelformat = video->fcc;
  69         fmt->fmt.pix.width = video->width;
  70         fmt->fmt.pix.height = video->height;
  71         fmt->fmt.pix.field = V4L2_FIELD_NONE;
  72         fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
  73         fmt->fmt.pix.sizeimage = video->imagesize;
  74         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
  75         fmt->fmt.pix.priv = 0;
  76
  77         return 0;
  78 }
  79
  80 static int
  81 uvc_v4l2_set_format(struct uvc_video *video, struct v4l2_format *fmt)
  82 {
  83         struct uvc_format *format;
  84         unsigned int imagesize;
  85         unsigned int bpl;
  86         unsigned int i;
  87
  88         for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
  89                 format = &uvc_formats[i];
  90                 if (format->fcc == fmt->fmt.pix.pixelformat)
  91                         break;
  92         }
  93
  94         if (i == ARRAY_SIZE(uvc_formats)) {
  95                 printk(KERN_INFO "Unsupported format 0x%08x.\n",
  96                         fmt->fmt.pix.pixelformat);
  97                 return -EINVAL;
  98         }
  99
 100         bpl = format->bpp * fmt->fmt.pix.width / 8;
 101         imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
 102
 103         video->fcc = format->fcc;
 104         video->bpp = format->bpp;
 105         video->width = fmt->fmt.pix.width;
 106         video->height = fmt->fmt.pix.height;
 107         video->imagesize = imagesize;
 108
 109         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 110         fmt->fmt.pix.bytesperline = bpl;
 111         fmt->fmt.pix.sizeimage = imagesize;
 112         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
 113         fmt->fmt.pix.priv = 0;
 114
 115         return 0;
 116 }
 117
 118 static int
 119 uvc_v4l2_open(struct file *file)
 120 {
 121         struct video_device *vdev = video_devdata(file);
 122         struct uvc_device *uvc = video_get_drvdata(vdev);
 123         struct uvc_file_handle *handle;
 124
 125         handle = kzalloc(sizeof(*handle), GFP_KERNEL);
 126         if (handle == NULL)
 127                 return -ENOMEM;
 128
 129         v4l2_fh_init(&handle->vfh, vdev);
 130         v4l2_fh_add(&handle->vfh);
 131
 132         handle->device = &uvc->video;
 133         file->private_data = &handle->vfh;
 134
 135         uvc_function_connect(uvc);
 136         return 0;
 137 }
 138
 139 static int
 140 uvc_v4l2_release(struct file *file)
 141 {
 142         struct video_device *vdev = video_devdata(file);
 143         struct uvc_device *uvc = video_get_drvdata(vdev);
 144         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 145         struct uvc_video *video = handle->device;
 146
 147         uvc_function_disconnect(uvc);
 148
 149         uvc_video_enable(video, 0);
 150         uvc_free_buffers(&video->queue);
 151
 152         file->private_data = NULL;
 153         v4l2_fh_del(&handle->vfh);
 154         v4l2_fh_exit(&handle->vfh);
 155         kfree(handle);
 156
 157         return 0;
 158 }
 159
 160 static long
 161 uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 162 {
 163         struct video_device *vdev = video_devdata(file);
 164         struct uvc_device *uvc = video_get_drvdata(vdev);
 165         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 166         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 167         struct uvc_video *video = &uvc->video;
 168         int ret = 0;
 169
 170         switch (cmd) {
 171         /* Query capabilities */
 172         case VIDIOC_QUERYCAP:
 173         {
 174                 struct v4l2_capability *cap = arg;
 175
 176                 memset(cap, 0, sizeof *cap);
 177                 strlcpy(cap->driver, "g_uvc", sizeof(cap->driver));
 178                 strlcpy(cap->card, cdev->gadget->name, sizeof(cap->card));
 179                 strlcpy(cap->bus_info, dev_name(&cdev->gadget->dev),
 180                         sizeof cap->bus_info);
 181                 cap->version = DRIVER_VERSION_NUMBER;
 182                 cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 183                 break;
 184         }
 185
 186         /* Get & Set format */
 187         case VIDIOC_G_FMT:
 188         {
 189                 struct v4l2_format *fmt = arg;
 190
 191                 if (fmt->type != video->queue.queue.type)
 192                         return -EINVAL;
 193
 194                 return uvc_v4l2_get_format(video, fmt);
 195         }
 196
 197         case VIDIOC_S_FMT:
 198         {
 199                 struct v4l2_format *fmt = arg;
 200
 201                 if (fmt->type != video->queue.queue.type)
 202                         return -EINVAL;
 203
 204                 return uvc_v4l2_set_format(video, fmt);
 205         }
 206
 207         /* Buffers & streaming */
 208         case VIDIOC_REQBUFS:
 209         {
 210                 struct v4l2_requestbuffers *rb = arg;
 211
 212                 if (rb->type != video->queue.queue.type)
 213                         return -EINVAL;
 214
 215                 ret = uvc_alloc_buffers(&video->queue, rb);
 216                 if (ret < 0)
 217                         return ret;
 218
 219                 ret = 0;
 220                 break;
 221         }
 222
 223         case VIDIOC_QUERYBUF:
 224         {
 225                 struct v4l2_buffer *buf = arg;
 226
 227                 return uvc_query_buffer(&video->queue, buf);
 228         }
 229
 230         case VIDIOC_QBUF:
 231                 if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
 232                         return ret;
 233
 234                 return uvc_video_pump(video);
 235
 236         case VIDIOC_DQBUF:
 237                 return uvc_dequeue_buffer(&video->queue, arg,
 238                         file->f_flags & O_NONBLOCK);
 239
 240         case VIDIOC_STREAMON:
 241         {
 242                 int *type = arg;
 243
 244                 if (*type != video->queue.queue.type)
 245                         return -EINVAL;
 246
 247                 /* Enable UVC video. */
 248                 ret = uvc_video_enable(video, 1);
 249                 if (ret < 0)
 250                         return ret;
 251
 252                 /*
 253                  * Complete the alternate setting selection setup phase now that
 254                  * userspace is ready to provide video frames.
 255                  */
 256                 uvc_function_setup_continue(uvc);
 257                 uvc->state = UVC_STATE_STREAMING;
 258
 259                 return 0;
 260         }
 261
 262         case VIDIOC_STREAMOFF:
 263         {
 264                 int *type = arg;
 265
 266                 if (*type != video->queue.queue.type)
 267                         return -EINVAL;
 268
 269                 return uvc_video_enable(video, 0);
 270         }
 271
 272         /* Events */
 273         case VIDIOC_DQEVENT:
 274         {
 275                 struct v4l2_event *event = arg;
 276
 277                 ret = v4l2_event_dequeue(&handle->vfh, event,
 278                                          file->f_flags & O_NONBLOCK);
 279                 if (ret == 0 && event->type == UVC_EVENT_SETUP) {
 280                         struct uvc_event *uvc_event = (void *)&event->u.data;
 281
 282                         /* Tell the complete callback to generate an event for
 283                          * the next request that will be enqueued by
 284                          * uvc_event_write.
 285                          */
 286                         uvc->event_setup_out =
 287                                 !(uvc_event->req.bRequestType & USB_DIR_IN);
 288                         uvc->event_length = uvc_event->req.wLength;
 289                 }
 290
 291                 return ret;
 292         }
 293
 294         case VIDIOC_SUBSCRIBE_EVENT:
 295         {
 296                 struct v4l2_event_subscription *sub = arg;
 297
 298                 if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
 299                         return -EINVAL;
 300
 301                 return v4l2_event_subscribe(&handle->vfh, arg, 2, NULL);
 302         }
 303
 304         case VIDIOC_UNSUBSCRIBE_EVENT:
 305                 return v4l2_event_unsubscribe(&handle->vfh, arg);
 306
 307         case UVCIOC_SEND_RESPONSE:
 308                 ret = uvc_send_response(uvc, arg);
 309                 break;
 310
 311         default:
 312                 return -ENOIOCTLCMD;
 313         }
 314
 315         return ret;
 316 }
 317
 318 static long
 319 uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 320 {
 321         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
 322 }
 323
 324 static int
 325 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 326 {
 327         struct video_device *vdev = video_devdata(file);
 328         struct uvc_device *uvc = video_get_drvdata(vdev);
 329
 330         return uvc_queue_mmap(&uvc->video.queue, vma);
 331 }
 332
 333 static unsigned int
 334 uvc_v4l2_poll(struct file *file, poll_table *wait)
 335 {
 336         struct video_device *vdev = video_devdata(file);
 337         struct uvc_device *uvc = video_get_drvdata(vdev);
 338
 339         return uvc_queue_poll(&uvc->video.queue, file, wait);
 340 }
 341
 342 #ifndef CONFIG_MMU
 343 static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
 344                 unsigned long addr, unsigned long len, unsigned long pgoff,
 345                 unsigned long flags)
 346 {
 347         struct video_device *vdev = video_devdata(file);
 348         struct uvc_device *uvc = video_get_drvdata(vdev);
 349
 350         return uvc_queue_get_unmapped_area(&uvc->video.queue, pgoff);
 351 }
 352 #endif
 353
 354 static struct v4l2_file_operations uvc_v4l2_fops = {
 355         .owner          = THIS_MODULE,
 356         .open           = uvc_v4l2_open,
 357         .release        = uvc_v4l2_release,
 358         .ioctl          = uvc_v4l2_ioctl,
 359         .mmap           = uvc_v4l2_mmap,
 360         .poll           = uvc_v4l2_poll,
 361 #ifndef CONFIG_MMU
 362         .get_unmapped_area = uvc_v4l2_get_unmapped_area,
 363 #endif
 364 };
 365