[PATCH v8 12/19] media: uvcvideo: Increase the size of UVC_METADATA_BUF_SIZE

[Ricardo Ribalda]

Hans has discovered that in his test device, for the H264 format
bytesused goes up to about 570, for YUYV it will actually go up
to a bit over 5000 bytes, and for MJPG up to about 2706 bytes.

We should also, according to V4L2_META_FMT_UVC docs, drop headers when
the buffer is full.

Credit-to: Hans Verkuil <hverk...@xs4all.nl>
Reviewed-by: Hans Verkuil <hverkuil-ci...@xs4all.nl>
Signed-off-by: Ricardo Ribalda <riba...@chromium.org>
---
 drivers/media/usb/uvc/uvc_video.c | 8 +++++---
 drivers/media/usb/uvc/uvcvideo.h  | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/media/usb/uvc/uvc_video.c 
b/drivers/media/usb/uvc/uvc_video.c
index 25fd8aa23529..ea2903dc3252 100644
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -1244,11 +1244,13 @@ static void uvc_video_decode_meta(struct uvc_streaming 
*stream,
        if (!meta_buf || length == 2)
                return;
 
+       /*
+        * According to V4L2_META_FMT_UVC docs, we should drop headers when
+        * the buffer is full.
+        */
        if (meta_buf->length - meta_buf->bytesused <
-           length + sizeof(meta->ns) + sizeof(meta->sof)) {
-               meta_buf->error = 1;
+           length + sizeof(meta->ns) + sizeof(meta->sof))
                return;
-       }
 
        has_pts = mem[1] & UVC_STREAM_PTS;
        has_scr = mem[1] & UVC_STREAM_SCR;
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index b81d3f65e52e..a26bbec8d37b 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -527,7 +527,7 @@ struct uvc_stats_stream {
        unsigned int max_sof;           /* Maximum STC.SOF value */
 };
 
-#define UVC_METADATA_BUF_SIZE 1024
+#define UVC_METADATA_BUF_SIZE 10240
 
 /**
  * struct uvc_copy_op: Context structure to schedule asynchronous memcpy
-- 
2.31.0.rc2.261.g7f71774620-goog