[PATCH v4 3/7] media: uvcvideo: Split uvc_stop_streaming()

From: Ricardo Ribalda
Date: Tue Jul 01 2025 - 02:45:53 EST


uvc_stop_streaming() is used for meta and video nodes. Split the function
in two to avoid confusion.

Use this opportunity to rename uvc_start_streaming() to
uvc_start_streaming_video(), as it is only called by the video nodes.

Reviewed-by: Hans de Goede <hansg@xxxxxxxxxx>
Signed-off-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20250616-uvc-fop-v4-3-250286570ee7@xxxxxxxxxxxx
Reviewed-by: Hans Verkuil <hverkuil@xxxxxxxxx>
Signed-off-by: Hans de Goede <hansg@xxxxxxxxxx>
---
drivers/media/usb/uvc/uvc_queue.c | 27 ++++++++++++++++++++-------
1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
index 8f9737ac729546683ca48f5e71ce3dfacbae2926..b11f56d62ec0495a8610580367486dfaa31c450d 100644
--- a/drivers/media/usb/uvc/uvc_queue.c
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -167,7 +167,7 @@ static void uvc_buffer_finish(struct vb2_buffer *vb)
uvc_video_clock_update(stream, vbuf, buf);
}

-static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
+static int uvc_start_streaming_video(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);
@@ -186,14 +186,22 @@ static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
return ret;
}

-static void uvc_stop_streaming(struct vb2_queue *vq)
+static void uvc_stop_streaming_video(struct vb2_queue *vq)
{
struct uvc_video_queue *queue = vb2_get_drv_priv(vq);

lockdep_assert_irqs_enabled();

- if (vq->type != V4L2_BUF_TYPE_META_CAPTURE)
- uvc_video_stop_streaming(uvc_queue_to_stream(queue));
+ uvc_video_stop_streaming(uvc_queue_to_stream(queue));
+
+ uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
+}
+
+static void uvc_stop_streaming_meta(struct vb2_queue *vq)
+{
+ struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
+
+ lockdep_assert_irqs_enabled();

uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
}
@@ -203,15 +211,20 @@ static const struct vb2_ops uvc_queue_qops = {
.buf_prepare = uvc_buffer_prepare,
.buf_queue = uvc_buffer_queue,
.buf_finish = uvc_buffer_finish,
- .start_streaming = uvc_start_streaming,
- .stop_streaming = uvc_stop_streaming,
+ .start_streaming = uvc_start_streaming_video,
+ .stop_streaming = uvc_stop_streaming_video,
};

static const struct vb2_ops uvc_meta_queue_qops = {
.queue_setup = uvc_queue_setup,
.buf_prepare = uvc_buffer_prepare,
.buf_queue = uvc_buffer_queue,
- .stop_streaming = uvc_stop_streaming,
+ /*
+ * .start_streaming is not provided here. Metadata relies on video
+ * streaming being active. If video isn't streaming, then no metadata
+ * will arrive either.
+ */
+ .stop_streaming = uvc_stop_streaming_meta,
};

int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)

--
2.50.0.727.gbf7dc18ff4-goog