On Thu Nov 28 14:51:43 2024 +0000, Isaac Scott wrote:
> Some cameras, such as the Sonix Technology Co. 292A, exhibit issues when
> running two parallel streams, causing USB packets to be dropped when an
> H.264 stream posts a keyframe while an MJPEG stream is running
> simultaneously. This occasionally causes the driver to erroneously
> output two consecutive JPEG images as a single frame.
>
> To fix this, we inspect the buffer, and trigger a new frame when we
> find an SOI.
>
> Signed-off-by: Isaac Scott <isaac.sc...@ideasonboard.com>
> Reviewed-by: Ricardo Ribalda <riba...@chromium.org>
> Link:
> https://lore.kernel.org/r/20241128145144.61475-2-isaac.sc...@ideasonboard.com
> Signed-off-by: Laurent Pinchart <laurent.pinch...@ideasonboard.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab+hua...@kernel.org>
Patch committed.
Thanks,
Mauro Carvalho Chehab
drivers/media/usb/uvc/uvc_video.c | 27 ++++++++++++++++++++++++++-
drivers/media/usb/uvc/uvcvideo.h | 1 +
2 files changed, 27 insertions(+), 1 deletion(-)
---
diff --git a/drivers/media/usb/uvc/uvc_video.c
b/drivers/media/usb/uvc/uvc_video.c
index 7efed64b81a2..e3567aeb0007 100644
--- a/drivers/media/usb/uvc/uvc_video.c
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -20,6 +20,7 @@
#include <linux/atomic.h>
#include <linux/unaligned.h>
+#include <media/jpeg.h>
#include <media/v4l2-common.h>
#include "uvcvideo.h"
@@ -1142,6 +1143,7 @@ static void uvc_video_stats_stop(struct uvc_streaming
*stream)
static int uvc_video_decode_start(struct uvc_streaming *stream,
struct uvc_buffer *buf, const u8 *data, int len)
{
+ u8 header_len;
u8 fid;
/*
@@ -1155,6 +1157,7 @@ static int uvc_video_decode_start(struct uvc_streaming
*stream,
return -EINVAL;
}
+ header_len = data[0];
fid = data[1] & UVC_STREAM_FID;
/*
@@ -1236,9 +1239,31 @@ static int uvc_video_decode_start(struct uvc_streaming
*stream,
return -EAGAIN;
}
+ /*
+ * Some cameras, when running two parallel streams (one MJPEG alongside
+ * another non-MJPEG stream), are known to lose the EOF packet for a
frame.
+ * We can detect the end of a frame by checking for a new SOI marker, as
+ * the SOI always lies on the packet boundary between two frames for
+ * these devices.
+ */
+ if (stream->dev->quirks & UVC_QUIRK_MJPEG_NO_EOF &&
+ (stream->cur_format->fcc == V4L2_PIX_FMT_MJPEG ||
+ stream->cur_format->fcc == V4L2_PIX_FMT_JPEG)) {
+ const u8 *packet = data + header_len;
+
+ if (len >= header_len + 2 &&
+ packet[0] == 0xff && packet[1] == JPEG_MARKER_SOI &&
+ buf->bytesused != 0) {
+ buf->state = UVC_BUF_STATE_READY;
+ buf->error = 1;
+ stream->last_fid ^= UVC_STREAM_FID;
+ return -EAGAIN;
+ }
+ }
+
stream->last_fid = fid;
- return data[0];
+ return header_len;
}
static inline enum dma_data_direction uvc_stream_dir(
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
index 3d196a696f46..5e388f05f3fc 100644
--- a/drivers/media/usb/uvc/uvcvideo.h
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -76,6 +76,7 @@
#define UVC_QUIRK_NO_RESET_RESUME 0x00004000
#define UVC_QUIRK_DISABLE_AUTOSUSPEND 0x00008000
#define UVC_QUIRK_INVALID_DEVICE_SOF 0x00010000
+#define UVC_QUIRK_MJPEG_NO_EOF 0x00020000
/* Format flags */
#define UVC_FMT_FLAG_COMPRESSED 0x00000001
