Em 20/07/2026 12:35, Baptiste Daroussin escreveu:
On Mon 20 Jul 14:24, Baptiste Daroussin wrote:
On Sun 19 Jul 14:03, Nilton Jose Rizzo wrote:
Em 19/07/2026 13:49, Baptiste Daroussin escreveu:
Le 18 juillet 2026 23:45:58 GMT+02:00, Nilton Jose Rizzo<[email protected]> a
écrit :
Em 18/07/2026 02:36, Baptiste Daroussin escreveu:
Le 14 juillet 2026 01:42:07 GMT+02:00, Nilton Jose Rizzo<[email protected]> a
écrit :
Hi all,
I upgraded my desktop last weekend and decided to try the new *uvideo*driver
from OpenBSD.
When I run |pwcview|, the image is displayed incorrectly: it is horizontally
duplicated and shows interlaced lines.
If I switch back to |webcamd|, the webcam works normally.
I also tested it with *Google Meet*and *Jitsi Meet*in Firefox.
On Google Meet, I receive a warning indicating that my webcam is not
functioning properly.
Has anyone experienced this issue or have any suggestions on how to
troubleshoot it?
My web cam is HD Pro C920 USB
ugen0.2: <HD Pro Webcam C920 Logitech, Inc.> at usbus0, cfg=0 md=HOST spd=HIGH
(480Mbps) pwr=ON (500mA)
$ usbconfig -v -d ugen0.2
ugen0.2: <HD Pro Webcam C920 Logitech, Inc.> at usbus0, cfg=0 md=HOST spd=HIGH
(480Mbps) pwr=ON (500mA)
ugen0.2.2: uaudio0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11,
addr 3>
bLength = 0x0012
bDescriptorType = 0x0001
bcdUSB = 0x0200
bDeviceClass = 0x00ef <Miscellaneous device>
bDeviceSubClass = 0x0002
bDeviceProtocol = 0x0001
bMaxPacketSize0 = 0x0040
idVendor = 0x046d
idProduct = 0x082d
bcdDevice = 0x0011
iManufacturer = 0x0000 <no string>
iProduct = 0x0002 <HD Pro Webcam C920>
iSerialNumber = 0x0001 <1BC69C1F>
bNumConfigurations = 0x0001
When uvideo load, show this message
uvideo0 on uhub1
uvideo0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11, addr 3>
on usbus0
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: too many PU descriptors found!
uvideo0: 3 format(s), iface_index=1, endpoint=0x81, psize=3060, isoc
uvideo0: default format: pixfmt=0x56595559, 640x480, max_fbuf=4147200
uvideo0: UVC camera on /dev/video0
try updating UVIDEO_MAX_PU and UVIDEO_MAX_CT from 8 to 32.
in sys/dev/usb/video/uvideo.c
best regards,
Bapt
I change these values, PU warnings was gone.
My Webcam not work fine yet.
See this jpeg screenshot from pwcview using default values to fps and
resolution (sif).
https://imgur.com/a/YG89hK5
ugen0.2: <vendor 0x046d HD Pro Webcam C920> at usbus0
uvideo0 on uhub1
uvideo0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11, addr 3>
on usbus0
uvideo0: 3 format(s), iface_index=1, endpoint=0x81, psize=3060, isoc
uvideo0: default format: pixfmt=0x56595559, 640x480, max_fbuf=4147200
uvideo0: UVC camera on /dev/video0
uaudio0 on uhub1
uaudio0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11, addr 3>
on usbus0
uaudio0: No playback.
uaudio0: Record[0]: 32000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms buffer.
(selected)
uaudio0: Record[0]: 24000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms buffer.
uaudio0: Record[0]: 16000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms buffer.
uaudio0: No MIDI sequencer.
pcm6 on uaudio0
uaudio0: No HID volume keys found.
uvideo0: stream open: nframes=51, psize=3060, maxVideoFrameSize=153600,
maxPayloadSize=800, alt=11, isoc
uvideo0: stream open: nframes=51, psize=3060, maxVideoFrameSize=153600,
maxPayloadSize=800, alt=11, isoc
on linux it has quirks for this model, I need to implement some. I ll come back
with a patch soon
bapt
I'd be happy to help improve this driver by providing more information about
this camera. Let me know what information would be useful.
Thank you Baptiste.
--
**************************
* Dr. Nilton Jose Rizzo *
* Engenheiro Eletrônico *
* Doutor pela COPPE/UFRJ *
* Telegram: @njrizzo *
**************************
I have pushed the quirks infrastructure from openbsd, can you try the following
patch on top of it? this is quirks I found for your model in linux uvc driver:
https://people.freebsd.org/~bapt/0001-uvideo-add-quirks-for-Logitech-C920-webcams.patch
Best regards,
Bapt
Actually try this version of the patch:
https://bapt.nours.eu/0001-uvideo-add-quirks-for-Logitech-C920-webcams.patch
Best regards,
Bapt
Hi Baptiste,
Sorry for the late reply.
I applied the patch, but unfortunately it didn't solve the problem.
After recompiling the kernel and rebooting the system, the webcam still
doesn't work properly.
I have to reset the USB bus manually using the following command:
|usbconfig reset|
After doing that, the webcam is detected again, but the image in
|pwcview|remains unchanged and still has the same duplicated/interlaced
appearance.
Google Meet and Jitsi Meet in Firefox also behave the same way as before.
The webcam's microphone works fine, but I still can't get any video from
the camera in |pwcview|, Google Meet, or Jitsi Meet.
Please let me know if you'd like me to test anything else or provide
additional debugging information.
More info about my system:
dmesg:
uvideo0 on uhub0
uvideo0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11,
addr 1> on usbus0
uvideo0: 3 format(s), iface_index=1, endpoint=0x81, psize=3060, isoc
uvideo0: default format: pixfmt=0x56595559, 640x480, max_fbuf=4147200
uvideo0: UVC camera on /dev/video0
uaudio0 on uhub0
uaudio0: <vendor 0x046d HD Pro Webcam C920, class 239/2, rev 2.00/0.11,
addr 1> on usbus0
uaudio0: No playback.
uaudio0: Record[0]: 32000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms
buffer. (selected)
uaudio0: Record[0]: 24000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms buffer.
uaudio0: Record[0]: 16000 Hz, 2 ch, 16-bit S-LE PCM format, 2x4ms buffer.
uaudio0: No MIDI sequencer.
pcm6 on uaudio0
uaudio0: No HID volume keys found.
umodem0 on uhub2
umodem0: <STMicroelectronics STM32 Virtual ComPort, class 2/2, rev
2.00/2.00, addr 4> on usbus1
umodem0: data interface 1, has no CM over data, has no break
em0: link state changed to UP
Security policy loaded: MAC/ntpd (mac_ntpd)
WARNING: sysctl vfs.zfs.min_auto_ashift is deprecated. Use
vfs.zfs.vdev.min_auto_ashift instead.
uvideo0: stream open: nframes=51, psize=3060, maxVideoFrameSize=153600,
maxPayloadSize=800, alt=11, isoc
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
uvideo0: could not SET probe: USB_ERR_TIMEOUT
$ uname -a
FreeBSD valfenda 16.0-CURRENT FreeBSD 16.0-CURRENT #19
main-4db3872aabc3-dirty: Thu Jul 23 01:07:56 -03 2026
rizzo@valfenda:/usr/obj/usr/src/amd64.amd64/sys/GENERIC-NODEBUG amd64
--
**************************
* Dr. Nilton Jose Rizzo *
* Engenheiro Eletrônico *
* Doutor pela COPPE/UFRJ *
* Telegram: @njrizzo *
**************************
