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
  14 #include <linux/kernel.h>
  15 #include <linux/device.h>
  16 #include <linux/errno.h>
  17 #include <linux/list.h>
  18 #include <linux/mutex.h>
  19 #include <linux/version.h>
  20 #include <linux/videodev2.h>
  21 #include <linux/vmalloc.h>
  22 #include <linux/wait.h>
  23
  24 #include <media/v4l2-dev.h>
  25 #include <media/v4l2-event.h>
  26 #include <media/v4l2-ioctl.h>
  27
  28 #include "uvc.h"
  29 #include "uvc_queue.h"
  30
  31 /* --------------------------------------------------------------------------
  32  * Requests handling
  33  */
  34
  35 static int
  36 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
  37 {
  38         struct usb_composite_dev *cdev = uvc->func.config->cdev;
  39         struct usb_request *req = uvc->control_req;
  40
  41         if (data->length < 0)
  42                 return usb_ep_set_halt(cdev->gadget->ep0);
  43
  44         req->length = min(uvc->event_length, data->length);
  45         req->zero = data->length < uvc->event_length;
  46         req->dma = DMA_ADDR_INVALID;
  47
  48         memcpy(req->buf, data->data, data->length);
  49
  50         return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
  51 }
  52
  53 /* --------------------------------------------------------------------------
  54  * V4L2
  55  */
  56
  57 struct uvc_format
  58 {
  59         u8 bpp;
  60         u32 fcc;
  61 };
  62
  63 static struct uvc_format uvc_formats[] = {
  64         { 16, V4L2_PIX_FMT_YUYV  },
  65         { 0,  V4L2_PIX_FMT_MJPEG },
  66 };
  67
  68 static int
  69 uvc_v4l2_get_format(struct uvc_video *video, struct v4l2_format *fmt)
  70 {
  71         fmt->fmt.pix.pixelformat = video->fcc;
  72         fmt->fmt.pix.width = video->width;
  73         fmt->fmt.pix.height = video->height;
  74         fmt->fmt.pix.field = V4L2_FIELD_NONE;
  75         fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
  76         fmt->fmt.pix.sizeimage = video->imagesize;
  77         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
  78         fmt->fmt.pix.priv = 0;
  79
  80         return 0;
  81 }
  82
  83 static int
  84 uvc_v4l2_set_format(struct uvc_video *video, struct v4l2_format *fmt)
  85 {
  86         struct uvc_format *format;
  87         unsigned int imagesize;
  88         unsigned int bpl;
  89         unsigned int i;
  90
  91         for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
  92                 format = &uvc_formats[i];
  93                 if (format->fcc == fmt->fmt.pix.pixelformat)
  94                         break;
  95         }
  96
  97         if (i == ARRAY_SIZE(uvc_formats)) {
  98                 printk(KERN_INFO "Unsupported format 0x%08x.\n",
  99                         fmt->fmt.pix.pixelformat);
 100                 return -EINVAL;
 101         }
 102
 103         bpl = format->bpp * fmt->fmt.pix.width / 8;
 104         imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
 105
 106         video->fcc = format->fcc;
 107         video->bpp = format->bpp;
 108         video->width = fmt->fmt.pix.width;
 109         video->height = fmt->fmt.pix.height;
 110         video->imagesize = imagesize;
 111
 112         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 113         fmt->fmt.pix.bytesperline = bpl;
 114         fmt->fmt.pix.sizeimage = imagesize;
 115         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
 116         fmt->fmt.pix.priv = 0;
 117
 118         return 0;
 119 }
 120
 121 static int
 122 uvc_v4l2_open(struct file *file)
 123 {
 124         struct video_device *vdev = video_devdata(file);
 125         struct uvc_device *uvc = video_get_drvdata(vdev);
 126         struct uvc_file_handle *handle;
 127         int ret;
 128
 129         handle = kzalloc(sizeof(*handle), GFP_KERNEL);
 130         if (handle == NULL)
 131                 return -ENOMEM;
 132
 133         ret = v4l2_fh_init(&handle->vfh, vdev);
 134         if (ret < 0)
 135                 goto error;
 136
 137         ret = v4l2_event_init(&handle->vfh);
 138         if (ret < 0)
 139                 goto error;
 140
 141         ret = v4l2_event_alloc(&handle->vfh, 8);
 142         if (ret < 0)
 143                 goto error;
 144
 145         v4l2_fh_add(&handle->vfh);
 146
 147         handle->device = &uvc->video;
 148         file->private_data = &handle->vfh;
 149
 150         uvc_function_connect(uvc);
 151         return 0;
 152
 153 error:
 154         v4l2_fh_exit(&handle->vfh);
 155         return ret;
 156 }
 157
 158 static int
 159 uvc_v4l2_release(struct file *file)
 160 {
 161         struct video_device *vdev = video_devdata(file);
 162         struct uvc_device *uvc = video_get_drvdata(vdev);
 163         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 164         struct uvc_video *video = handle->device;
 165
 166         uvc_function_disconnect(uvc);
 167
 168         uvc_video_enable(video, 0);
 169         mutex_lock(&video->queue.mutex);
 170         if (uvc_free_buffers(&video->queue) < 0)
 171                 printk(KERN_ERR "uvc_v4l2_release: Unable to free "
 172                                 "buffers.\n");
 173         mutex_unlock(&video->queue.mutex);
 174
 175         file->private_data = NULL;
 176         v4l2_fh_del(&handle->vfh);
 177         v4l2_fh_exit(&handle->vfh);
 178         kfree(handle);
 179         return 0;
 180 }
 181
 182 static long
 183 uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 184 {
 185         struct video_device *vdev = video_devdata(file);
 186         struct uvc_device *uvc = video_get_drvdata(vdev);
 187         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 188         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 189         struct uvc_video *video = &uvc->video;
 190         int ret = 0;
 191
 192         switch (cmd) {
 193         /* Query capabilities */
 194         case VIDIOC_QUERYCAP:
 195         {
 196                 struct v4l2_capability *cap = arg;
 197
 198                 memset(cap, 0, sizeof *cap);
 199                 strncpy(cap->driver, "g_uvc", sizeof(cap->driver));
 200                 strncpy(cap->card, cdev->gadget->name, sizeof(cap->card));
 201                 strncpy(cap->bus_info, dev_name(&cdev->gadget->dev),
 202                         sizeof cap->bus_info);
 203                 cap->version = DRIVER_VERSION_NUMBER;
 204                 cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 205                 break;
 206         }
 207
 208         /* Get & Set format */
 209         case VIDIOC_G_FMT:
 210         {
 211                 struct v4l2_format *fmt = arg;
 212
 213                 if (fmt->type != video->queue.type)
 214                         return -EINVAL;
 215
 216                 return uvc_v4l2_get_format(video, fmt);
 217         }
 218
 219         case VIDIOC_S_FMT:
 220         {
 221                 struct v4l2_format *fmt = arg;
 222
 223                 if (fmt->type != video->queue.type)
 224                         return -EINVAL;
 225
 226                 return uvc_v4l2_set_format(video, fmt);
 227         }
 228
 229         /* Buffers & streaming */
 230         case VIDIOC_REQBUFS:
 231         {
 232                 struct v4l2_requestbuffers *rb = arg;
 233
 234                 if (rb->type != video->queue.type ||
 235                     rb->memory != V4L2_MEMORY_MMAP)
 236                         return -EINVAL;
 237
 238                 ret = uvc_alloc_buffers(&video->queue, rb->count,
 239                                         video->imagesize);
 240                 if (ret < 0)
 241                         return ret;
 242
 243                 rb->count = ret;
 244                 ret = 0;
 245                 break;
 246         }
 247
 248         case VIDIOC_QUERYBUF:
 249         {
 250                 struct v4l2_buffer *buf = arg;
 251
 252                 if (buf->type != video->queue.type)
 253                         return -EINVAL;
 254
 255                 return uvc_query_buffer(&video->queue, buf);
 256         }
 257
 258         case VIDIOC_QBUF:
 259                 if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
 260                         return ret;
 261
 262                 return uvc_video_pump(video);
 263
 264         case VIDIOC_DQBUF:
 265                 return uvc_dequeue_buffer(&video->queue, arg,
 266                         file->f_flags & O_NONBLOCK);
 267
 268         case VIDIOC_STREAMON:
 269         {
 270                 int *type = arg;
 271
 272                 if (*type != video->queue.type)
 273                         return -EINVAL;
 274
 275                 return uvc_video_enable(video, 1);
 276         }
 277
 278         case VIDIOC_STREAMOFF:
 279         {
 280                 int *type = arg;
 281
 282                 if (*type != video->queue.type)
 283                         return -EINVAL;
 284
 285                 return uvc_video_enable(video, 0);
 286         }
 287
 288         /* Events */
 289         case VIDIOC_DQEVENT:
 290         {
 291                 struct v4l2_event *event = arg;
 292
 293                 ret = v4l2_event_dequeue(&handle->vfh, event,
 294                                          file->f_flags & O_NONBLOCK);
 295                 if (ret == 0 && event->type == UVC_EVENT_SETUP) {
 296                         struct uvc_event *uvc_event = (void *)&event->u.data;
 297
 298                         /* Tell the complete callback to generate an event for
 299                          * the next request that will be enqueued by
 300                          * uvc_event_write.
 301                          */
 302                         uvc->event_setup_out =
 303                                 !(uvc_event->req.bRequestType & USB_DIR_IN);
 304                         uvc->event_length = uvc_event->req.wLength;
 305                 }
 306
 307                 return ret;
 308         }
 309
 310         case VIDIOC_SUBSCRIBE_EVENT:
 311         {
 312                 struct v4l2_event_subscription *sub = arg;
 313
 314                 if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
 315                         return -EINVAL;
 316
 317                 return v4l2_event_subscribe(&handle->vfh, arg);
 318         }
 319
 320         case VIDIOC_UNSUBSCRIBE_EVENT:
 321                 return v4l2_event_unsubscribe(&handle->vfh, arg);
 322
 323         case UVCIOC_SEND_RESPONSE:
 324                 ret = uvc_send_response(uvc, arg);
 325                 break;
 326
 327         default:
 328                 return -ENOIOCTLCMD;
 329         }
 330
 331         return ret;
 332 }
 333
 334 static long
 335 uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 336 {
 337         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
 338 }
 339
 340 static int
 341 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 342 {
 343         struct video_device *vdev = video_devdata(file);
 344         struct uvc_device *uvc = video_get_drvdata(vdev);
 345
 346         return uvc_queue_mmap(&uvc->video.queue, vma);
 347 }
 348
 349 static unsigned int
 350 uvc_v4l2_poll(struct file *file, poll_table *wait)
 351 {
 352         struct video_device *vdev = video_devdata(file);
 353         struct uvc_device *uvc = video_get_drvdata(vdev);
 354         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 355         unsigned int mask = 0;
 356
 357         poll_wait(file, &handle->vfh.events->wait, wait);
 358         if (v4l2_event_pending(&handle->vfh))
 359                 mask |= POLLPRI;
 360
 361         mask |= uvc_queue_poll(&uvc->video.queue, file, wait);
 362
 363         return mask;
 364 }
 365
 366 static struct v4l2_file_operations uvc_v4l2_fops = {
 367         .owner          = THIS_MODULE,
 368         .open           = uvc_v4l2_open,
 369         .release        = uvc_v4l2_release,
 370         .ioctl          = uvc_v4l2_ioctl,
 371         .mmap           = uvc_v4l2_mmap,
 372         .poll           = uvc_v4l2_poll,
 373 };
 374