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