tech@,

Some V4L consumers, for example libwebrtc which is used by firefox, uses
bus_info to find the desired webcam.

Our logic with hardcoded string leads that firefox uses /dev/video0, and
switch to another webcam simple doesn't work.

This behaviour of Linux uvc_meta_v4l2_querycap which uses constant as
driver name, and device as bus_info.

Ok?

Index: sys/dev/usb/uvideo.c
===================================================================
RCS file: /home/cvs/src/sys/dev/usb/uvideo.c,v
diff -u -p -u -p -r1.231 uvideo.c
--- sys/dev/usb/uvideo.c	22 Dec 2024 20:30:04 -0000	1.231
+++ sys/dev/usb/uvideo.c	28 Dec 2024 15:08:42 -0000
@@ -2931,9 +2931,9 @@ uvideo_querycap(void *v, struct v4l2_cap
 	struct uvideo_softc *sc = v;

 	bzero(caps, sizeof(*caps));
-	strlcpy(caps->driver, DEVNAME(sc), sizeof(caps->driver));
+	strlcpy(caps->driver, "uvideo", sizeof(caps->driver));
 	strlcpy(caps->card, sc->sc_udev->product, sizeof(caps->card));
-	strlcpy(caps->bus_info, "usb", sizeof(caps->bus_info));
+	strlcpy(caps->bus_info, DEVNAME(sc), sizeof(caps->bus_info));

 	caps->version = 1;
 	caps->device_caps = V4L2_CAP_VIDEO_CAPTURE


--
wbr, Kirill