Hi Laurent, Not sure whether that's a kernel or a user-space problem, but UVC related anyway. I've got a UVC 1.5 (!) Logitech camera, that used to work fine with earlier kernels. I now installed "media 4.16" and saw, that the kernel log was filling with messages like uvcvideo: Failed to query (GET_MIN) UVC control 2 on unit 1: -32 (exp. 1). The expected /dev/video[01] nodes were not created correctly, and the hard-drive was getting full very quickly. The latter was happening because the the /var/log/uvcdynctrl-udev.log file was growing. A truncated sample is attached. At its bottom you see messages [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. repeating, which continues even if the camera is unplugged. The kernel is the head of the master branch of git://linuxtv.org/media_tree.git Just figured out this commit From: Edgar Thier <info@xxxxxxxxxxxxxx> Date: Thu, 12 Oct 2017 03:54:17 -0400 Subject: [PATCH] media: uvcvideo: Apply flags from device to actual properties as the culprit. Without it everything is back to normal. Thanks Guennadi
============================================================================== uvcdynctrl script version 0.3 running from '/lib/udev/uvcdynctrl' ============================================================================== uvcdynctrl script version 0.3 running from '/lib/udev/uvcdynctrl' Triggered at Wed Apr 11 09:08:26 CEST 2018 ACTION='add' DEVLINKS='/dev/v4l/by-path/pci-0000:00:14.0-usb-0:1:1.0-video-index0 /dev/v4l/by-id/usb-046d_Logitech_Webcam_C930e_816415EE-video-index0' DEVNAME='/dev/video0' DEVPATH='/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/video4linux/video0' ID_BUS='usb' ID_FOR_SEAT='video4linux-pci-0000_00_14_0-usb-0_1_1_0' ID_MODEL='Logitech_Webcam_C930e' ID_MODEL_ENC='Logitech\x20Webcam\x20C930e' ID_MODEL_ID='0843' ID_PATH='pci-0000:00:14.0-usb-0:1:1.0' ID_PATH_TAG='pci-0000_00_14_0-usb-0_1_1_0' ID_REVISION='0013' ID_SERIAL='046d_Logitech_Webcam_C930e_816415EE' ID_SERIAL_SHORT='816415EE' ID_TYPE='video' ID_USB_DRIVER='uvcvideo' ID_USB_INTERFACES=':0e0100:0e0200:010100:010200:' ID_USB_INTERFACE_NUM='00' ID_V4L_CAPABILITIES=':capture:' ID_V4L_PRODUCT='Logitech Webcam C930e' ID_V4L_VERSION='2' ID_VENDOR='046d' ID_VENDOR_ENC='046d' ID_VENDOR_ID='046d' IFS=' ' MAJOR='81' MINOR='0' OPTIND='1' PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' PPID='853' PS1='# ' PS2='> ' PS4='+ ' PWD='/' SEQNUM='1895' SUBSYSTEM='video4linux' TAGS=':uaccess:seat:' USEC_INITIALIZED='175470181' debug='1' logfile='/var/log/uvcdynctrl-udev.log' uvcdynctrlpath='uvcdynctrl' version='0.3' Triggered at Wed Apr 11 09:08:26 CEST 2018 VID of new device: '046d' PID of new device: '0843' Executing command: 'uvcdynctrl -d /dev/video0 --addctrl=046d:0843' ACTION='add' DEVLINKS='/dev/v4l/by-id/usb-046d_Logitech_Webcam_C930e_816415EE-video-index1 /dev/v4l/by-path/pci-0000:00:14.0-usb-0:1:1.0-video-index1' DEVNAME='/dev/video1' DEVPATH='/devices/pci0000:00/0000:00:14.0/usb2/2-1/2-1:1.0/video4linux/video1' ID_BUS='usb' ID_FOR_SEAT='video4linux-pci-0000_00_14_0-usb-0_1_1_0' ID_MODEL='Logitech_Webcam_C930e' ID_MODEL_ENC='Logitech\x20Webcam\x20C930e' ID_MODEL_ID='0843' ID_PATH='pci-0000:00:14.0-usb-0:1:1.0' ID_PATH_TAG='pci-0000_00_14_0-usb-0_1_1_0' ID_REVISION='0013' ID_SERIAL='046d_Logitech_Webcam_C930e_816415EE' ID_SERIAL_SHORT='816415EE' ID_TYPE='video' ID_USB_DRIVER='uvcvideo' ID_USB_INTERFACES=':0e0100:0e0200:010100:010200:' ID_USB_INTERFACE_NUM='00' ID_V4L_CAPABILITIES=':capture:' ID_V4L_PRODUCT='Logitech Webcam C930e' ID_V4L_VERSION='2' ID_VENDOR='046d' ID_VENDOR_ENC='046d' ID_VENDOR_ID='046d' IFS=' ' MAJOR='81' MINOR='1' OPTIND='1' PATH='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin' PPID='858' PS1='# ' PS2='> ' PS4='+ ' PWD='/' SEQNUM='1896' SUBSYSTEM='video4linux' TAGS=':uaccess:seat:' USEC_INITIALIZED='175470183' debug='1' logfile='/var/log/uvcdynctrl-udev.log' uvcdynctrlpath='uvcdynctrl' version='0.3' VID of new device: '046d' PID of new device: '0843' Executing command: 'uvcdynctrl -d /dev/video1 --addctrl=046d:0843' [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher control ID if a control query fails. A workaround has been enabled. [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher
