Created attachment 531884 [details] .config I have recently updated from kernel 4.15.9 to 4.16.8 and discovered that some change in v4l2 caused that my USB microscope is not working any more, see below. The only change was in the gentoo kernel and matching nvidia proprietary drivers. The builtin laptop camera /dev/video0 surprisingly works with both kernels, but the microscope /dev/video1 only with the old one. I am attaching .config mplayer -zoom tv:// -tv driver=v4l2:width=640:height=480:device=/dev/video1:input=0:noaudio:outfmt=yuy2:fps=30 MPlayer 1.3.0-6.4.0 (C) 2000-2016 MPlayer Team Playing tv://. TV file format detected. Selected driver: v4l2 name: Video 4 Linux 2 input author: Martin Olschewski <olschewski@zpr.uni-koeln.de> comment: first try, more to come ;-) v4l2: ioctl get format failed: Invalid argument v4l2: ioctl set mute failed: Inappropriate ioctl for device v4l2: 0 frames successfully processed, 0 frames dropped. Exiting... (End of file) dmesg [13170.545177] usb 2-1.6: new high-speed USB device number 17 using ehci-pci [13170.655798] usb 2-1.6: New USB device found, idVendor=0ac8, idProduct=3610 [13170.655800] usb 2-1.6: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [13170.655801] usb 2-1.6: Product: Vimicro USB2.0 UVC PC Camera [13170.655802] usb 2-1.6: Manufacturer: Vimicro Co.,ltd [13170.669550] uvcvideo: Found UVC 1.00 device Vimicro USB2.0 UVC PC Camera (0ac8:3610) [13170.671248] uvcvideo 2-1.6:1.0: Entity type for entity Processing 2 was not initialized! [13170.671249] uvcvideo 2-1.6:1.0: Entity type for entity Camera 1 was not initialized! [13170.671250] uvcvideo 2-1.6:1.0: Entity type for entity Extension 4 was not initialized! [13170.671301] input: Vimicro USB2.0 UVC PC Camera: V as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.6/2-1.6:1.0/input/input25 [13622.726417] usb 2-1.6: USB disconnect, device number 17 dmesg with the old kernel Bus 002 Device 012: ID 0ac8:3610 Z-Star Microelectronics Corp. [ 224.606680] usb 2-1.5: new high-speed USB device number 13 using ehci-pci [ 224.717416] usb 2-1.5: New USB device found, idVendor=0ac8, idProduct=3610 [ 224.717418] usb 2-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 224.717419] usb 2-1.5: Product: Vimicro USB2.0 UVC PC Camera [ 224.717420] usb 2-1.5: Manufacturer: Vimicro Co.,ltd [ 224.731165] uvcvideo: Found UVC 1.00 device Vimicro USB2.0 UVC PC Camera (0ac8:3610) [ 224.732872] uvcvideo 2-1.5:1.0: Entity type for entity Processing 2 was not initialized! [ 224.732875] uvcvideo 2-1.5:1.0: Entity type for entity Camera 1 was not initialized! [ 224.732876] uvcvideo 2-1.5:1.0: Entity type for entity Extension 4 was not initialized! [ 224.732965] input: Vimicro USB2.0 UVC PC Camera: V as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.0/input/input24 emerge --info Portage 2.3.24 (python 3.4.8-final-0, default/linux/amd64/17.0, gcc-6.4.0, glibc-2.25-r11, 4.15.9-gentoo x86_64) ================================================================= System uname: Linux-4.15.9-gentoo-x86_64-Intel-R-_Core-TM-_i7-4810MQ_CPU_@_2.80GHz-with-gentoo-2.4.1 KiB Mem: 16337456 total, 14958316 free KiB Swap: 8388604 total, 8388604 free Timestamp of repository gentoo: Wed, 16 May 2018 10:30:02 +0000 Head commit of repository gentoo: 688da4db0a7e233f95f2c292c8c8d7b8fa439274 sh bash 4.4_p12 ld GNU ld (Gentoo 2.29.1 p3) 2.29.1 app-shells/bash: 4.4_p12::gentoo dev-java/java-config: 2.2.0-r4::gentoo dev-lang/perl: 5.24.3-r1::gentoo dev-lang/python: 2.7.14-r1::gentoo, 3.4.8::gentoo, 3.5.5::gentoo, 3.6.5::gentoo dev-util/cmake: 3.9.6::gentoo dev-util/pkgconfig: 0.29.2::gentoo sys-apps/baselayout: 2.4.1-r2::gentoo sys-apps/openrc: 0.34.11::gentoo sys-apps/sandbox: 2.13::gentoo sys-devel/autoconf: 2.13::gentoo, 2.69-r4::gentoo sys-devel/automake: 1.11.6-r3::gentoo, 1.14.1-r2::gentoo, 1.15.1-r2::gentoo, 1.16.1-r1::gentoo sys-devel/binutils: 2.25.1-r1::gentoo, 2.26.1::gentoo, 2.28-r2::gentoo, 2.28.1::gentoo, 2.29.1-r1::gentoo sys-devel/gcc: 4.5.4::gentoo, 4.8.5::gentoo, 4.9.3::gentoo, 4.9.4::gentoo, 5.4.0-r3::gentoo, 6.4.0-r1::gentoo, 7.2.0-r1::gentoo, 7.3.0-r1::gentoo sys-devel/gcc-config: 1.8-r1::gentoo sys-devel/libtool: 2.4.6-r3::gentoo sys-devel/make: 4.2.1::gentoo sys-kernel/linux-headers: 4.13::gentoo (virtual/os-headers) sys-libs/glibc: 2.25-r11::gentoo Repositories: gentoo location: /usr/portage sync-type: rsync sync-uri: rsync://rsync.gentoo.org/gentoo-portage priority: -1000 sync-rsync-verify-metamanifest: no sync-rsync-extra-opts: science location: /var/lib/layman/science masters: gentoo priority: 1 crossdev location: /opt/portage masters: gentoo science priority: 2 ACCEPT_KEYWORDS="amd64" ACCEPT_LICENSE="*" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-O2 -march=native -mtune=native -fno-omit-frame-pointer -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc /etc/stunnel/stunnel.conf /usr/share/config /usr/share/gnupg/qualified.txt /var/bind /var/lib/hsqldb /var/lib/i2pd/certificates" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/dconf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/gentoo-release /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c" CXXFLAGS="-O2 -march=native -mtune=native -fno-omit-frame-pointer -pipe" DISTDIR="/usr/portage/distfiles" FCFLAGS="-O2 -pipe" FEATURES="assume-digests binpkg-logs config-protect-if-modified distlocks ebuild-locks fixlafiles merge-sync multilib-strict news parallel-fetch preserve-libs protect-owned sandbox sfperms splitdebug strict unknown-features-warn unmerge-logs unmerge-orphans userfetch userpriv usersandbox usersync xattr" FFLAGS="-O2 -pipe" GENTOO_MIRRORS="http://gentoo.supp.name/ http://ftp.fi.muni.cz/pub/linux/gentoo/ http://147.251.48.205/pub/linux/gentoo/ http://gentoo.mirror.dkm.cz/pub/gentoo/ http://86.49.49.49/pub/gentoo/ ftp://gentoo.mirror.dkm.cz/pub/gentoo/ ftp://ftp.wh2.tu-dresden.de/pub/mirrors/gentoo ftp://141.76.119.131/pub/mirrors/gentoo ftp://ftp.sh.cvut.cz/MIRRORS/gentoo ftp://mirror.switch.ch/mirror/gentoo/ http://gentoo.supp.name/ rsync://gentoo.mirror.dkm.cz/gentoo/ http://gentoo.mirror.web4u.cz/" LANG="C" LDFLAGS="-Wl,-O1 -Wl,--as-needed" MAKEOPTS="-j8" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --omit-dir-times --compress --force --whole-file --delete --stats --human-readable --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages --exclude=/.git" PORTAGE_TMPDIR="/scratch/tmp" USE="X acl aes alsa amd64 berkdb bzip2 cli crypt cxx dri fortran gcj gdbm hal iconv ipv6 lapack latex linguas_cs linguas_de linguas_en linguas_nl linguas_sk mbox mmx modules multilib multislot ncurses nls nptl openmp pam pcre readline seccomp sse sse2 sse3 sse4 ssl static-libs systemtap tcpd tetex unicode xattr zlib" ABI_X86="64 32" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" APACHE2_MODULES="authn_core authz_core socache_shmcb unixd actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache cgi cgid dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" CALLIGRA_FEATURES="karbon plan sheets stage words" COLLECTD_PLUGINS="df interface irq load memory rrdtool swap syslog" CPU_FLAGS_X86="mmx mmxext sse sse2" ELIBC="glibc" GPSD_PROTOCOLS="ashtech aivdm earthmate evermore fv18 garmin garmintxt gpsclock isync itrax mtk3301 nmea ntrip navcom oceanserver oldstyle oncore rtcm104v2 rtcm104v3 sirf skytraq superstar2 timing tsip tripmate tnt ublox ubx" INPUT_DEVICES="keyboard mouse evdev synaptics" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" LIBREOFFICE_EXTENSIONS="presenter-console presenter-minimizer" OFFICE_IMPLEMENTATION="libreoffice" PHP_TARGETS="php5-6 php7-0" POSTGRES_TARGETS="postgres9_5" PYTHON_SINGLE_TARGET="python3_5" PYTHON_TARGETS="python2_7 python3_4 python3_5" RUBY_TARGETS="ruby22 ruby23" USERLAND="GNU" VIDEO_CARDS="nvidia nouveau vesa nv fbdev v4l vga" XTABLES_ADDONS="quota2 psd pknock lscan length2 ipv4options ipset ipp2p iface geoip fuzzy condition tee tarpit sysrq steal rawnat logmark ipmark dhcpmac delude chaos account" Unset: CC, CPPFLAGS, CTARGET, CXX, EMERGE_DEFAULT_OPTS, INSTALL_MASK, LC_ALL, LINGUAS, PORTAGE_BUNZIP2_COMMAND, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS
The problem disappeared in 4.17.0. Just as a note, with two real devices, I get /dev/video0 .. /dev/video3, video0 and video2 work, the other two are spurious.
