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         v4l2_fh_init(&handle->vfh, vdev);
 134
 135         ret = v4l2_event_alloc(&handle->vfh, 8);
 136         if (ret < 0)
 137                 goto error;
 138
 139         v4l2_fh_add(&handle->vfh);
 140
 141         handle->device = &uvc->video;
 142         file->private_data = &handle->vfh;
 143
 144         uvc_function_connect(uvc);
 145         return 0;
 146
 147 error:
 148         v4l2_fh_exit(&handle->vfh);
 149         return ret;
 150 }
 151
 152 static int
 153 uvc_v4l2_release(struct file *file)
 154 {
 155         struct video_device *vdev = video_devdata(file);
 156         struct uvc_device *uvc = video_get_drvdata(vdev);
 157         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 158         struct uvc_video *video = handle->device;
 159
 160         uvc_function_disconnect(uvc);
 161
 162         uvc_video_enable(video, 0);
 163         mutex_lock(&video->queue.mutex);
 164         if (uvc_free_buffers(&video->queue) < 0)
 165                 printk(KERN_ERR "uvc_v4l2_release: Unable to free "
 166                                 "buffers.\n");
 167         mutex_unlock(&video->queue.mutex);
 168
 169         file->private_data = NULL;
 170         v4l2_fh_del(&handle->vfh);
 171         v4l2_fh_exit(&handle->vfh);
 172         kfree(handle);
 173         return 0;
 174 }
 175
 176 static long
 177 uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 178 {
 179         struct video_device *vdev = video_devdata(file);
 180         struct uvc_device *uvc = video_get_drvdata(vdev);
 181         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 182         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 183         struct uvc_video *video = &uvc->video;
 184         int ret = 0;
 185
 186         switch (cmd) {
 187         /* Query capabilities */
 188         case VIDIOC_QUERYCAP:
 189         {
 190                 struct v4l2_capability *cap = arg;
 191
 192                 memset(cap, 0, sizeof *cap);
 193                 strncpy(cap->driver, "g_uvc", sizeof(cap->driver));
 194                 strncpy(cap->card, cdev->gadget->name, sizeof(cap->card));
 195                 strncpy(cap->bus_info, dev_name(&cdev->gadget->dev),
 196                         sizeof cap->bus_info);
 197                 cap->version = DRIVER_VERSION_NUMBER;
 198                 cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 199                 break;
 200         }
 201
 202         /* Get & Set format */
 203         case VIDIOC_G_FMT:
 204         {
 205                 struct v4l2_format *fmt = arg;
 206
 207                 if (fmt->type != video->queue.type)
 208                         return -EINVAL;
 209
 210                 return uvc_v4l2_get_format(video, fmt);
 211         }
 212
 213         case VIDIOC_S_FMT:
 214         {
 215                 struct v4l2_format *fmt = arg;
 216
 217                 if (fmt->type != video->queue.type)
 218                         return -EINVAL;
 219
 220                 return uvc_v4l2_set_format(video, fmt);
 221         }
 222
 223         /* Buffers & streaming */
 224         case VIDIOC_REQBUFS:
 225         {
 226                 struct v4l2_requestbuffers *rb = arg;
 227
 228                 if (rb->type != video->queue.type ||
 229                     rb->memory != V4L2_MEMORY_MMAP)
 230                         return -EINVAL;
 231
 232                 ret = uvc_alloc_buffers(&video->queue, rb->count,
 233                                         video->imagesize);
 234                 if (ret < 0)
 235                         return ret;
 236
 237                 rb->count = ret;
 238                 ret = 0;
 239                 break;
 240         }
 241
 242         case VIDIOC_QUERYBUF:
 243         {
 244                 struct v4l2_buffer *buf = arg;
 245
 246                 if (buf->type != video->queue.type)
 247                         return -EINVAL;
 248
 249                 return uvc_query_buffer(&video->queue, buf);
 250         }
 251
 252         case VIDIOC_QBUF:
 253                 if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
 254                         return ret;
 255
 256                 return uvc_video_pump(video);
 257
 258         case VIDIOC_DQBUF:
 259                 return uvc_dequeue_buffer(&video->queue, arg,
 260                         file->f_flags & O_NONBLOCK);
 261
 262         case VIDIOC_STREAMON:
 263         {
 264                 int *type = arg;
 265
 266                 if (*type != video->queue.type)
 267                         return -EINVAL;
 268
 269                 return uvc_video_enable(video, 1);
 270         }
 271
 272         case VIDIOC_STREAMOFF:
 273         {
 274                 int *type = arg;
 275
 276                 if (*type != video->queue.type)
 277                         return -EINVAL;
 278
 279                 return uvc_video_enable(video, 0);
 280         }
 281
 282         /* Events */
 283         case VIDIOC_DQEVENT:
 284         {
 285                 struct v4l2_event *event = arg;
 286
 287                 ret = v4l2_event_dequeue(&handle->vfh, event,
 288                                          file->f_flags & O_NONBLOCK);
 289                 if (ret == 0 && event->type == UVC_EVENT_SETUP) {
 290                         struct uvc_event *uvc_event = (void *)&event->u.data;
 291
 292                         /* Tell the complete callback to generate an event for
 293                          * the next request that will be enqueued by
 294                          * uvc_event_write.
 295                          */
 296                         uvc->event_setup_out =
 297                                 !(uvc_event->req.bRequestType & USB_DIR_IN);
 298                         uvc->event_length = uvc_event->req.wLength;
 299                 }
 300
 301                 return ret;
 302         }
 303
 304         case VIDIOC_SUBSCRIBE_EVENT:
 305         {
 306                 struct v4l2_event_subscription *sub = arg;
 307
 308                 if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
 309                         return -EINVAL;
 310
 311                 return v4l2_event_subscribe(&handle->vfh, arg);
 312         }
 313
 314         case VIDIOC_UNSUBSCRIBE_EVENT:
 315                 return v4l2_event_unsubscribe(&handle->vfh, arg);
 316
 317         case UVCIOC_SEND_RESPONSE:
 318                 ret = uvc_send_response(uvc, arg);
 319                 break;
 320
 321         default:
 322                 return -ENOIOCTLCMD;
 323         }
 324
 325         return ret;
 326 }
 327
 328 static long
 329 uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 330 {
 331         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
 332 }
 333
 334 static int
 335 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 336 {
 337         struct video_device *vdev = video_devdata(file);
 338         struct uvc_device *uvc = video_get_drvdata(vdev);
 339
 340         return uvc_queue_mmap(&uvc->video.queue, vma);
 341 }
 342
 343 static unsigned int
 344 uvc_v4l2_poll(struct file *file, poll_table *wait)
 345 {
 346         struct video_device *vdev = video_devdata(file);
 347         struct uvc_device *uvc = video_get_drvdata(vdev);
 348         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 349         unsigned int mask = 0;
 350
 351         poll_wait(file, &handle->vfh.wait, wait);
 352         if (v4l2_event_pending(&handle->vfh))
 353                 mask |= POLLPRI;
 354
 355         mask |= uvc_queue_poll(&uvc->video.queue, file, wait);
 356
 357         return mask;
 358 }
 359
 360 static struct v4l2_file_operations uvc_v4l2_fops = {
 361         .owner          = THIS_MODULE,
 362         .open           = uvc_v4l2_open,
 363         .release        = uvc_v4l2_release,
 364         .ioctl          = uvc_v4l2_ioctl,
 365         .mmap           = uvc_v4l2_mmap,
 366         .poll           = uvc_v4l2_poll,
 367 };
 368