diff mbox series

[v7,1/2] media: uvcvideo: Implement dual stream quirk to fix loss of usb packets

Message ID 20241112112926.17848-2-isaac.scott@ideasonboard.com (mailing list archive)
State New
Headers show
Series Fix Sonix Technology MJPEG streams | expand

Commit Message

Isaac Scott Nov. 12, 2024, 11:29 a.m. UTC
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.scott@ideasonboard.com>
---
 drivers/media/usb/uvc/uvc_video.c | 27 ++++++++++++++++++++++++++-
 drivers/media/usb/uvc/uvcvideo.h  |  1 +
 2 files changed, 27 insertions(+), 1 deletion(-)

Comments

Ricardo Ribalda Nov. 14, 2024, 7:47 p.m. UTC | #1
Hi Isaac

I am curious... How is this v7?

Remember to run
 scripts/checkpatch.pl --strict -g HEAD

It is complaining about an open parenthesis match here. Not the end of
the world, but rather fix it locally than discussing :)

Totally optional... maybe you can add to the cover-letter a run of
yavta -c /dev/videoX
with and without the patch. So people can see practically what changes.

Regards!

On Tue, 12 Nov 2024 at 12:33, Isaac Scott <isaac.scott@ideasonboard.com> 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.scott@ideasonboard.com>
> ---
>  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 e00f38dd07d9..9bb41362c48d 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"
> @@ -1116,6 +1117,7 @@ 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;
>
>         /*
> @@ -1129,6 +1131,7 @@ static int uvc_video_decode_start(struct uvc_streaming *stream,
>                 return -EINVAL;
>         }
>
> +       header_len = data[0];
>         fid = data[1] & UVC_STREAM_FID;
>
>         /*
> @@ -1210,9 +1213,31 @@ 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 = ((const u8 *)data) + header_len;
Do you need the (const u8 *) casting here? . I believe data has
exactly that datatype
> +
> +               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 b7d24a853ce4..040073326a24 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
> --
> 2.43.0
>
>
diff mbox series

Patch

diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
index e00f38dd07d9..9bb41362c48d 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"
@@ -1116,6 +1117,7 @@  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;
 
 	/*
@@ -1129,6 +1131,7 @@  static int uvc_video_decode_start(struct uvc_streaming *stream,
 		return -EINVAL;
 	}
 
+	header_len = data[0];
 	fid = data[1] & UVC_STREAM_FID;
 
 	/*
@@ -1210,9 +1213,31 @@  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 = ((const u8 *)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 b7d24a853ce4..040073326a24 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