2021-09-15 20:07:49

by Ricardo Ribalda

[permalink] [raw]
Subject: [PATCH 1/3] media: uvc: Extend documentation of uvc_video_clock_decode()

Make a explicit reference to uvc 1.5, explaining how the algorithm
supports the different behaviour of uvc 1.1 and 1.5.

Signed-off-by: Ricardo Ribalda <[email protected]>
---
drivers/media/usb/uvc/uvc_video.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index e16464606b14..77f4090f27d2 100644
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -505,6 +505,9 @@ uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf,

/* To limit the amount of data, drop SCRs with an SOF identical to the
* previous one.
+ * This filtering is also needed for supporting UVC 1.5. Where all the
+ * data packages of the same frame contains the same sof. In that case
+ * only the first one will match the host_sof.
*/
dev_sof = get_unaligned_le16(&data[header_size - 2]);
if (dev_sof == stream->clock.last_sof)
--
2.33.0.309.g3052b89438-goog