Patch "media: uvcvideo: Accept invalid bFormatIndex and bFrameIndex values" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    media: uvcvideo: Accept invalid bFormatIndex and bFrameIndex values

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     media-uvcvideo-accept-invalid-bformatindex-and-bfram.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b18bc1e88e18b027ec62d69d3f1fab5d7e32d371
Author: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Date:   Sun Dec 20 15:11:13 2020 +0100

    media: uvcvideo: Accept invalid bFormatIndex and bFrameIndex values
    
    [ Upstream commit dc9455ffae02d7b7fb51ba1e007fffcb9dc5d890 ]
    
    The Renkforce RF AC4K 300 Action Cam 4K reports invalid bFormatIndex and
    bFrameIndex values when negotiating the video probe and commit controls.
    The UVC descriptors report a single supported format and frame size,
    with bFormatIndex and bFrameIndex both equal to 2, but the video probe
    and commit controls report bFormatIndex and bFrameIndex set to 1.
    
    The device otherwise operates correctly, but the driver rejects the
    values and fails the format try operation. Fix it by ignoring the
    invalid indices, and assuming that the format and frame requested by the
    driver are accepted by the device.
    
    Link: https://bugzilla.kernel.org/show_bug.cgi?id=210767
    
    Fixes: 8a652a17e3c0 ("media: uvcvideo: Ensure all probed info is returned to v4l2")
    Reported-by: Till Dörges <doerges@xxxxxxxxxxxx>
    Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
    Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 5e6f3153b5ff8..7d60dd3b0bd85 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -248,7 +248,9 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 		goto done;
 
 	/* After the probe, update fmt with the values returned from
-	 * negotiation with the device.
+	 * negotiation with the device. Some devices return invalid bFormatIndex
+	 * and bFrameIndex values, in which case we can only assume they have
+	 * accepted the requested format as-is.
 	 */
 	for (i = 0; i < stream->nformats; ++i) {
 		if (probe->bFormatIndex == stream->format[i].index) {
@@ -257,11 +259,10 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 		}
 	}
 
-	if (i == stream->nformats) {
-		uvc_trace(UVC_TRACE_FORMAT, "Unknown bFormatIndex %u\n",
+	if (i == stream->nformats)
+		uvc_trace(UVC_TRACE_FORMAT,
+			  "Unknown bFormatIndex %u, using default\n",
 			  probe->bFormatIndex);
-		return -EINVAL;
-	}
 
 	for (i = 0; i < format->nframes; ++i) {
 		if (probe->bFrameIndex == format->frame[i].bFrameIndex) {
@@ -270,11 +271,10 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 		}
 	}
 
-	if (i == format->nframes) {
-		uvc_trace(UVC_TRACE_FORMAT, "Unknown bFrameIndex %u\n",
+	if (i == format->nframes)
+		uvc_trace(UVC_TRACE_FORMAT,
+			  "Unknown bFrameIndex %u, using default\n",
 			  probe->bFrameIndex);
-		return -EINVAL;
-	}
 
 	fmt->fmt.pix.width = frame->wWidth;
 	fmt->fmt.pix.height = frame->wHeight;