diff options
Diffstat (limited to 'drivers/media/usb/uvc/uvc_queue.c')
-rw-r--r-- | drivers/media/usb/uvc/uvc_queue.c | 110 |
1 files changed, 87 insertions, 23 deletions
diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c index 8964e16f2b22..682698ec1118 100644 --- a/drivers/media/usb/uvc/uvc_queue.c +++ b/drivers/media/usb/uvc/uvc_queue.c @@ -142,6 +142,7 @@ static void uvc_buffer_queue(struct vb2_buffer *vb) spin_lock_irqsave(&queue->irqlock, flags); if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) { + kref_init(&buf->ref); list_add_tail(&buf->queue, &queue->irqqueue); } else { /* If the device is disconnected return the buffer to userspace @@ -169,18 +170,19 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count) { struct uvc_video_queue *queue = vb2_get_drv_priv(vq); struct uvc_streaming *stream = uvc_queue_to_stream(queue); - unsigned long flags; int ret; + lockdep_assert_irqs_enabled(); + queue->buf_used = 0; - ret = uvc_video_enable(stream, 1); + ret = uvc_video_start_streaming(stream); if (ret == 0) return 0; - spin_lock_irqsave(&queue->irqlock, flags); + spin_lock_irq(&queue->irqlock); uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED); - spin_unlock_irqrestore(&queue->irqlock, flags); + spin_unlock_irq(&queue->irqlock); return ret; } @@ -188,14 +190,15 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count) static void uvc_stop_streaming(struct vb2_queue *vq) { struct uvc_video_queue *queue = vb2_get_drv_priv(vq); - unsigned long flags; + + lockdep_assert_irqs_enabled(); if (vq->type != V4L2_BUF_TYPE_META_CAPTURE) - uvc_video_enable(uvc_queue_to_stream(queue), 0); + uvc_video_stop_streaming(uvc_queue_to_stream(queue)); - spin_lock_irqsave(&queue->irqlock, flags); + spin_lock_irq(&queue->irqlock); uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR); - spin_unlock_irqrestore(&queue->irqlock, flags); + spin_unlock_irq(&queue->irqlock); } static const struct vb2_ops uvc_queue_qops = { @@ -430,32 +433,93 @@ void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect) spin_unlock_irqrestore(&queue->irqlock, flags); } -struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, - struct uvc_buffer *buf) +/* + * uvc_queue_get_current_buffer: Obtain the current working output buffer + * + * Buffers may span multiple packets, and even URBs, therefore the active buffer + * remains on the queue until the EOF marker. + */ +static struct uvc_buffer * +__uvc_queue_get_current_buffer(struct uvc_video_queue *queue) +{ + if (list_empty(&queue->irqqueue)) + return NULL; + + return list_first_entry(&queue->irqqueue, struct uvc_buffer, queue); +} + +struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue) { struct uvc_buffer *nextbuf; unsigned long flags; + spin_lock_irqsave(&queue->irqlock, flags); + nextbuf = __uvc_queue_get_current_buffer(queue); + spin_unlock_irqrestore(&queue->irqlock, flags); + + return nextbuf; +} + +/* + * uvc_queue_buffer_requeue: Requeue a buffer on our internal irqqueue + * + * Reuse a buffer through our internal queue without the need to 'prepare'. + * The buffer will be returned to userspace through the uvc_buffer_queue call if + * the device has been disconnected. + */ +static void uvc_queue_buffer_requeue(struct uvc_video_queue *queue, + struct uvc_buffer *buf) +{ + buf->error = 0; + buf->state = UVC_BUF_STATE_QUEUED; + buf->bytesused = 0; + vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0); + + uvc_buffer_queue(&buf->buf.vb2_buf); +} + +static void uvc_queue_buffer_complete(struct kref *ref) +{ + struct uvc_buffer *buf = container_of(ref, struct uvc_buffer, ref); + struct vb2_buffer *vb = &buf->buf.vb2_buf; + struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue); + if ((queue->flags & UVC_QUEUE_DROP_CORRUPTED) && buf->error) { - buf->error = 0; - buf->state = UVC_BUF_STATE_QUEUED; - buf->bytesused = 0; - vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0); - return buf; + uvc_queue_buffer_requeue(queue, buf); + return; } + buf->state = buf->error ? UVC_BUF_STATE_ERROR : UVC_BUF_STATE_DONE; + vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused); + vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE); +} + +/* + * Release a reference on the buffer. Complete the buffer when the last + * reference is released. + */ +void uvc_queue_buffer_release(struct uvc_buffer *buf) +{ + kref_put(&buf->ref, uvc_queue_buffer_complete); +} + +/* + * Remove this buffer from the queue. Lifetime will persist while async actions + * are still running (if any), and uvc_queue_buffer_release will give the buffer + * back to VB2 when all users have completed. + */ +struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue, + struct uvc_buffer *buf) +{ + struct uvc_buffer *nextbuf; + unsigned long flags; + spin_lock_irqsave(&queue->irqlock, flags); list_del(&buf->queue); - if (!list_empty(&queue->irqqueue)) - nextbuf = list_first_entry(&queue->irqqueue, struct uvc_buffer, - queue); - else - nextbuf = NULL; + nextbuf = __uvc_queue_get_current_buffer(queue); spin_unlock_irqrestore(&queue->irqlock, flags); - buf->state = buf->error ? UVC_BUF_STATE_ERROR : UVC_BUF_STATE_DONE; - vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused); - vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE); + uvc_queue_buffer_release(buf); return nextbuf; } |