V4L/DVB (10104): uvcvideo: Add support for video output devices

Extend the range of supported UVC devices by allowing video output devices
matching the following structure:

TT_STREAMING -> VC_PROCESSING_UNIT -> VC_EXTENSION_UNIT{0,n} -> OTT_*

Video output devices are reported with the V4L2_CAP_VIDEO_OUTPUT capability
flag and are subject to the same restrictions as video input devices.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 18 insertions, 5 deletions

diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c
index 5646a6a32939..42546342e97d 100644
--- a/drivers/media/video/uvc/uvc_queue.c
+++ b/drivers/media/video/uvc/uvc_queue.c
@@ -79,12 +79,13 @@
  *
  */
 
-void uvc_queue_init(struct uvc_video_queue *queue)
+void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
         mutex_init(&queue->mutex);
         spin_lock_init(&queue->irqlock);
         INIT_LIST_HEAD(&queue->mainqueue);
         INIT_LIST_HEAD(&queue->irqqueue);
+        queue->type = type;
 }
 
 /*
@@ -132,7 +133,7 @@ int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
                 queue->buffer[i].buf.index = i;
                 queue->buffer[i].buf.m.offset = i * bufsize;
                 queue->buffer[i].buf.length = buflength;
-                queue->buffer[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+                queue->buffer[i].buf.type = queue->type;
                 queue->buffer[i].buf.sequence = 0;
                 queue->buffer[i].buf.field = V4L2_FIELD_NONE;
                 queue->buffer[i].buf.memory = V4L2_MEMORY_MMAP;
@@ -226,7 +227,7 @@ int uvc_queue_buffer(struct uvc_video_queue *queue,
 
         uvc_trace(UVC_TRACE_CAPTURE, "Queuing buffer %u.\n", v4l2_buf->index);
 
-        if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
+        if (v4l2_buf->type != queue->type ||
             v4l2_buf->memory != V4L2_MEMORY_MMAP) {
                 uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) "
                         "and/or memory (%u).\n", v4l2_buf->type,
@@ -249,6 +250,13 @@ int uvc_queue_buffer(struct uvc_video_queue *queue,
                 goto done;
         }
 
+        if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
+            v4l2_buf->bytesused > buf->buf.length) {
+                uvc_trace(UVC_TRACE_CAPTURE, "[E] Bytes used out of bounds.\n");
+                ret = -EINVAL;
+                goto done;
+        }
+
         spin_lock_irqsave(&queue->irqlock, flags);
         if (queue->flags & UVC_QUEUE_DISCONNECTED) {
                 spin_unlock_irqrestore(&queue->irqlock, flags);
@@ -256,7 +264,11 @@ int uvc_queue_buffer(struct uvc_video_queue *queue,
                 goto done;
         }
         buf->state = UVC_BUF_STATE_QUEUED;
-        buf->buf.bytesused = 0;
+        if (v4l2_buf->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+                buf->buf.bytesused = 0;
+        else
+                buf->buf.bytesused = v4l2_buf->bytesused;
+
         list_add_tail(&buf->stream, &queue->mainqueue);
         list_add_tail(&buf->queue, &queue->irqqueue);
         spin_unlock_irqrestore(&queue->irqlock, flags);
@@ -289,7 +301,7 @@ int uvc_dequeue_buffer(struct uvc_video_queue *queue,
         struct uvc_buffer *buf;
         int ret = 0;
 
-        if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
+        if (v4l2_buf->type != queue->type ||
             v4l2_buf->memory != V4L2_MEMORY_MMAP) {
                 uvc_trace(UVC_TRACE_CAPTURE, "[E] Invalid buffer type (%u) "
                         "and/or memory (%u).\n", v4l2_buf->type,
@@ -397,6 +409,7 @@ int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
                 }
                 queue->sequence = 0;
                 queue->flags |= UVC_QUEUE_STREAMING;
+                queue->buf_used = 0;
         } else {
                 uvc_queue_cancel(queue, 0);
                 INIT_LIST_HEAD(&queue->mainqueue);