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/version.h>
  19 #include <linux/videodev2.h>
  20 #include <linux/vmalloc.h>
  21 #include <linux/wait.h>
  22
  23 #include <media/v4l2-dev.h>
  24 #include <media/v4l2-event.h>
  25 #include <media/v4l2-ioctl.h>
  26
  27 #include "uvc.h"
  28 #include "uvc_queue.h"
  29
  30 /* --------------------------------------------------------------------------
  31  * Requests handling
  32  */
  33
  34 static int
  35 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
  36 {
  37         struct usb_composite_dev *cdev = uvc->func.config->cdev;
  38         struct usb_request *req = uvc->control_req;
  39
  40         if (data->length < 0)
  41                 return usb_ep_set_halt(cdev->gadget->ep0);
  42
  43         req->length = min(uvc->event_length, data->length);
  44         req->zero = data->length < uvc->event_length;
  45         req->dma = DMA_ADDR_INVALID;
  46
  47         memcpy(req->buf, data->data, data->length);
  48
  49         return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
  50 }
  51
  52 /* --------------------------------------------------------------------------
  53  * V4L2
  54  */
  55
  56 struct uvc_format
  57 {
  58         u8 bpp;
  59         u32 fcc;
  60 };
  61
  62 static struct uvc_format uvc_formats[] = {
  63         { 16, V4L2_PIX_FMT_YUYV  },
  64         { 0,  V4L2_PIX_FMT_MJPEG },
  65 };
  66
  67 static int
  68 uvc_v4l2_get_format(struct uvc_video *video, struct v4l2_format *fmt)
  69 {
  70         fmt->fmt.pix.pixelformat = video->fcc;
  71         fmt->fmt.pix.width = video->width;
  72         fmt->fmt.pix.height = video->height;
  73         fmt->fmt.pix.field = V4L2_FIELD_NONE;
  74         fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
  75         fmt->fmt.pix.sizeimage = video->imagesize;
  76         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
  77         fmt->fmt.pix.priv = 0;
  78
  79         return 0;
  80 }
  81
  82 static int
  83 uvc_v4l2_set_format(struct uvc_video *video, struct v4l2_format *fmt)
  84 {
  85         struct uvc_format *format;
  86         unsigned int imagesize;
  87         unsigned int bpl;
  88         unsigned int i;
  89
  90         for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
  91                 format = &uvc_formats[i];
  92                 if (format->fcc == fmt->fmt.pix.pixelformat)
  93                         break;
  94         }
  95
  96         if (i == ARRAY_SIZE(uvc_formats)) {
  97                 printk(KERN_INFO "Unsupported format 0x%08x.\n",
  98                         fmt->fmt.pix.pixelformat);
  99                 return -EINVAL;
 100         }
 101
 102         bpl = format->bpp * fmt->fmt.pix.width / 8;
 103         imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
 104
 105         video->fcc = format->fcc;
 106         video->bpp = format->bpp;
 107         video->width = fmt->fmt.pix.width;
 108         video->height = fmt->fmt.pix.height;
 109         video->imagesize = imagesize;
 110
 111         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 112         fmt->fmt.pix.bytesperline = bpl;
 113         fmt->fmt.pix.sizeimage = imagesize;
 114         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
 115         fmt->fmt.pix.priv = 0;
 116
 117         return 0;
 118 }
 119
 120 static int
 121 uvc_v4l2_open(struct file *file)
 122 {
 123         struct video_device *vdev = video_devdata(file);
 124         struct uvc_device *uvc = video_get_drvdata(vdev);
 125         struct uvc_file_handle *handle;
 126
 127         handle = kzalloc(sizeof(*handle), GFP_KERNEL);
 128         if (handle == NULL)
 129                 return -ENOMEM;
 130
 131         v4l2_fh_init(&handle->vfh, vdev);
 132         v4l2_fh_add(&handle->vfh);
 133
 134         handle->device = &uvc->video;
 135         file->private_data = &handle->vfh;
 136
 137         uvc_function_connect(uvc);
 138         return 0;
 139 }
 140
 141 static int
 142 uvc_v4l2_release(struct file *file)
 143 {
 144         struct video_device *vdev = video_devdata(file);
 145         struct uvc_device *uvc = video_get_drvdata(vdev);
 146         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 147         struct uvc_video *video = handle->device;
 148
 149         uvc_function_disconnect(uvc);
 150
 151         uvc_video_enable(video, 0);
 152         mutex_lock(&video->queue.mutex);
 153         if (uvc_free_buffers(&video->queue) < 0)
 154                 printk(KERN_ERR "uvc_v4l2_release: Unable to free "
 155                                 "buffers.\n");
 156         mutex_unlock(&video->queue.mutex);
 157
 158         file->private_data = NULL;
 159         v4l2_fh_del(&handle->vfh);
 160         v4l2_fh_exit(&handle->vfh);
 161         kfree(handle);
 162         return 0;
 163 }
 164
 165 static long
 166 uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 167 {
 168         struct video_device *vdev = video_devdata(file);
 169         struct uvc_device *uvc = video_get_drvdata(vdev);
 170         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 171         struct usb_composite_dev *cdev = uvc->func.config->cdev;
 172         struct uvc_video *video = &uvc->video;
 173         int ret = 0;
 174
 175         switch (cmd) {
 176         /* Query capabilities */
 177         case VIDIOC_QUERYCAP:
 178         {
 179                 struct v4l2_capability *cap = arg;
 180
 181                 memset(cap, 0, sizeof *cap);
 182                 strncpy(cap->driver, "g_uvc", sizeof(cap->driver));
 183                 strncpy(cap->card, cdev->gadget->name, sizeof(cap->card));
 184                 strncpy(cap->bus_info, dev_name(&cdev->gadget->dev),
 185                         sizeof cap->bus_info);
 186                 cap->version = DRIVER_VERSION_NUMBER;
 187                 cap->capabilities = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
 188                 break;
 189         }
 190
 191         /* Get & Set format */
 192         case VIDIOC_G_FMT:
 193         {
 194                 struct v4l2_format *fmt = arg;
 195
 196                 if (fmt->type != video->queue.type)
 197                         return -EINVAL;
 198
 199                 return uvc_v4l2_get_format(video, fmt);
 200         }
 201
 202         case VIDIOC_S_FMT:
 203         {
 204                 struct v4l2_format *fmt = arg;
 205
 206                 if (fmt->type != video->queue.type)
 207                         return -EINVAL;
 208
 209                 return uvc_v4l2_set_format(video, fmt);
 210         }
 211
 212         /* Buffers & streaming */
 213         case VIDIOC_REQBUFS:
 214         {
 215                 struct v4l2_requestbuffers *rb = arg;
 216
 217                 if (rb->type != video->queue.type ||
 218                     rb->memory != V4L2_MEMORY_MMAP)
 219                         return -EINVAL;
 220
 221                 ret = uvc_alloc_buffers(&video->queue, rb->count,
 222                                         video->imagesize);
 223                 if (ret < 0)
 224                         return ret;
 225
 226                 rb->count = ret;
 227                 ret = 0;
 228                 break;
 229         }
 230
 231         case VIDIOC_QUERYBUF:
 232         {
 233                 struct v4l2_buffer *buf = arg;
 234
 235                 if (buf->type != video->queue.type)
 236                         return -EINVAL;
 237
 238                 return uvc_query_buffer(&video->queue, buf);
 239         }
 240
 241         case VIDIOC_QBUF:
 242                 if ((ret = uvc_queue_buffer(&video->queue, arg)) < 0)
 243                         return ret;
 244
 245                 return uvc_video_pump(video);
 246
 247         case VIDIOC_DQBUF:
 248                 return uvc_dequeue_buffer(&video->queue, arg,
 249                         file->f_flags & O_NONBLOCK);
 250
 251         case VIDIOC_STREAMON:
 252         {
 253                 int *type = arg;
 254
 255                 if (*type != video->queue.type)
 256                         return -EINVAL;
 257
 258                 return uvc_video_enable(video, 1);
 259         }
 260
 261         case VIDIOC_STREAMOFF:
 262         {
 263                 int *type = arg;
 264
 265                 if (*type != video->queue.type)
 266                         return -EINVAL;
 267
 268                 return uvc_video_enable(video, 0);
 269         }
 270
 271         /* Events */
 272         case VIDIOC_DQEVENT:
 273         {
 274                 struct v4l2_event *event = arg;
 275
 276                 ret = v4l2_event_dequeue(&handle->vfh, event,
 277                                          file->f_flags & O_NONBLOCK);
 278                 if (ret == 0 && event->type == UVC_EVENT_SETUP) {
 279                         struct uvc_event *uvc_event = (void *)&event->u.data;
 280
 281                         /* Tell the complete callback to generate an event for
 282                          * the next request that will be enqueued by
 283                          * uvc_event_write.
 284                          */
 285                         uvc->event_setup_out =
 286                                 !(uvc_event->req.bRequestType & USB_DIR_IN);
 287                         uvc->event_length = uvc_event->req.wLength;
 288                 }
 289
 290                 return ret;
 291         }
 292
 293         case VIDIOC_SUBSCRIBE_EVENT:
 294         {
 295                 struct v4l2_event_subscription *sub = arg;
 296
 297                 if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
 298                         return -EINVAL;
 299
 300                 return v4l2_event_subscribe(&handle->vfh, arg, 2);
 301         }
 302
 303         case VIDIOC_UNSUBSCRIBE_EVENT:
 304                 return v4l2_event_unsubscribe(&handle->vfh, arg);
 305
 306         case UVCIOC_SEND_RESPONSE:
 307                 ret = uvc_send_response(uvc, arg);
 308                 break;
 309
 310         default:
 311                 return -ENOIOCTLCMD;
 312         }
 313
 314         return ret;
 315 }
 316
 317 static long
 318 uvc_v4l2_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 319 {
 320         return video_usercopy(file, cmd, arg, uvc_v4l2_do_ioctl);
 321 }
 322
 323 static int
 324 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 325 {
 326         struct video_device *vdev = video_devdata(file);
 327         struct uvc_device *uvc = video_get_drvdata(vdev);
 328
 329         return uvc_queue_mmap(&uvc->video.queue, vma);
 330 }
 331
 332 static unsigned int
 333 uvc_v4l2_poll(struct file *file, poll_table *wait)
 334 {
 335         struct video_device *vdev = video_devdata(file);
 336         struct uvc_device *uvc = video_get_drvdata(vdev);
 337         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 338         unsigned int mask = 0;
 339
 340         poll_wait(file, &handle->vfh.wait, wait);
 341         if (v4l2_event_pending(&handle->vfh))
 342                 mask |= POLLPRI;
 343
 344         mask |= uvc_queue_poll(&uvc->video.queue, file, wait);
 345
 346         return mask;
 347 }
 348
 349 static struct v4l2_file_operations uvc_v4l2_fops = {
 350         .owner          = THIS_MODULE,
 351         .open           = uvc_v4l2_open,
 352         .release        = uvc_v4l2_release,
 353         .ioctl          = uvc_v4l2_ioctl,
 354         .mmap           = uvc_v4l2_mmap,
 355         .poll           = uvc_v4l2_poll,
 356 };
 357