Udev Webcam Regel gelesen, aber nicht respektiert?


8

Ich habe zwei USB-Webcams auf dem Computer, aber beim Booten wechseln sie manchmal die /dev/videoNummer. Die Lösung für dieses Problem scheint darin zu bestehen, eine neue udevRegel zu erstellen . Ich habe diese Regel hinzugefügt
/etc/udev/rules.d/jj-video.rules:

Fix Webcam 1

KERNEL=="video1", SUBSYSTEM=="video4linux", SUBSYSTEMS=="usb", ATTRS{idVendor}=="1d6b", ATTRS{idProduct}=="0001", SYMLINK+="webcam1"

Fix Webcam 2

KERNEL=="video2", SUBSYSTEM=="video4linux", ATTR{name}=="Logitech QuickCam Pro 3000", KERNELS=="0000:00:1d.0", SUBSYSTEMS=="pci", DRIVERS=="uhci_hcd", ATTRS{vendor}=="0x8086", ATTRS##{device}=="0x2658", SYMLINK+="webcam2"

Die webcamSymlinks werden jedoch nicht erstellt. Ich habe viele verschiedene Kombinationen in dieser Datei ausprobiert. Die vorliegenden sind nur meine letzten Versuche.

Ich fand die Parameter in:

jjk@eee-old:~$ udevadm info -a -p $(udevadm info -q path -p /class/video4linux/video1)  

Udevadm-Informationen beginnen mit dem vom Devpath angegebenen Gerät und gehen dann die Kette der übergeordneten Geräte entlang. Es druckt für jedes gefundene Gerät alle möglichen Attribute im Schlüsselformat der udev-Regeln. Eine übereinstimmende Regel kann aus den Attributen des Geräts und den Attributen eines einzelnen übergeordneten Geräts bestehen.

 looking at device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1':
    KERNEL=="video1"
    SUBSYSTEM=="video4linux"
    DRIVER==""
    ATTR{name}=="Logitech QuickCam Pro 3000"
    ATTR{index}=="0"
    ATTR{button}=="0"

  looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0':
    KERNELS=="2-2:1.0"
    SUBSYSTEMS=="usb"
    DRIVERS=="Philips webcam"
    ATTRS{bInterfaceNumber}=="00"
    ATTRS{bAlternateSetting}==" 9"
    ATTRS{bNumEndpoints}=="02"
    ATTRS{bInterfaceClass}=="0a"
    ATTRS{bInterfaceSubClass}=="ff"
    ATTRS{bInterfaceProtocol}=="00"
    ATTRS{supports_autosuspend}=="0"

  looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2/2-2':
    KERNELS=="2-2"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{configuration}==""
    ATTRS{bNumInterfaces}==" 3"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bmAttributes}=="a0"
    ATTRS{bMaxPower}=="500mA"
    ATTRS{urbnum}=="371076"
    ATTRS{idVendor}=="046d"
    ATTRS{idProduct}=="08b0"
    ATTRS{bcdDevice}=="0002"
    ATTRS{bDeviceClass}=="00"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{bMaxPacketSize0}=="8"
    ATTRS{speed}=="12"
    ATTRS{busnum}=="2"
    ATTRS{devnum}=="2"
    ATTRS{devpath}=="2"
    ATTRS{version}==" 1.10"
    ATTRS{maxchild}=="0"
    ATTRS{quirks}=="0x0"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{authorized}=="1"
    ATTRS{serial}=="01402100A5000000"

  looking at parent device '/devices/pci0000:00/0000:00:1d.0/usb2':
    KERNELS=="usb2"
    SUBSYSTEMS=="usb"
    DRIVERS=="usb"
    ATTRS{configuration}==""
    ATTRS{bNumInterfaces}==" 1"
    ATTRS{bConfigurationValue}=="1"
    ATTRS{bmAttributes}=="e0"
    ATTRS{bMaxPower}=="  0mA"
    ATTRS{urbnum}=="34"
    ATTRS{idVendor}=="1d6b"
    ATTRS{idProduct}=="0001"
    ATTRS{bcdDevice}=="0302"
    ATTRS{bDeviceClass}=="09"
    ATTRS{bDeviceSubClass}=="00"
    ATTRS{bDeviceProtocol}=="00"
    ATTRS{bNumConfigurations}=="1"
    ATTRS{bMaxPacketSize0}=="64"
    ATTRS{speed}=="12"
    ATTRS{busnum}=="2"
    ATTRS{devnum}=="1"
    ATTRS{devpath}=="0"
    ATTRS{version}==" 1.10"
    ATTRS{maxchild}=="2"
    ATTRS{quirks}=="0x0"
    ATTRS{avoid_reset_quirk}=="0"
    ATTRS{authorized}=="1"
    ATTRS{manufacturer}=="Linux 3.2.0-29-generic uhci_hcd"
    ATTRS{product}=="UHCI Host Controller"
    ATTRS{serial}=="0000:00:1d.0"
    ATTRS{authorized_default}=="1"

  looking at parent device '/devices/pci0000:00/0000:00:1d.0':
    KERNELS=="0000:00:1d.0"
    SUBSYSTEMS=="pci"
    DRIVERS=="uhci_hcd"
    ATTRS{vendor}=="0x8086"
    ATTRS{device}=="0x2658"
    ATTRS{subsystem_vendor}=="0x1043"
    ATTRS{subsystem_device}=="0x82d8"
    ATTRS{class}=="0x0c0300"
    ATTRS{irq}=="23"
    ATTRS{local_cpus}=="ff"
    ATTRS{local_cpulist}=="0-7"
    ATTRS{dma_mask_bits}=="32"
    ATTRS{consistent_dma_mask_bits}=="32"
    ATTRS{broken_parity_status}=="0"
    ATTRS{msi_bus}==""

  looking at parent device '/devices/pci0000:00':
    KERNELS=="pci0000:00"
    SUBSYSTEMS==""
    DRIVERS==""

jjk@eee-old:~$ 

Und das Setup getestet:

sudo udevadm --debug test /sys/class/video4linux/video1

main: runtime dir '/run/udev'
run_command: calling: test
adm_test: version 175
This program is for debugging only, it does not run any program,
specified by a RUN key. It may show incorrect results, because
some values may be different, or not available at a simulation run.

parse_file: reading '/lib/udev/rules.d/40-crda.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-fuse.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-gnupg.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-hplip.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-ia64.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-inputattach.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-libgphoto2-2.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-libsane.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-ppc.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-usb_modeswitch.rules' as rules file
parse_file: reading '/lib/udev/rules.d/40-xserver-xorg-video-intel.rules' as rules file
parse_file: reading '/lib/udev/rules.d/42-qemu-usb.rules' as rules file
parse_file: reading '/lib/udev/rules.d/50-firmware.rules' as rules file
parse_file: reading '/lib/udev/rules.d/50-udev-default.rules' as rules file
parse_file: reading '/lib/udev/rules.d/55-dm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/56-hpmud_support.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-cdrom_id.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-pcmcia.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-alsa.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-input.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-serial.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-storage-dm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-storage-tape.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-storage.rules' as rules file
parse_file: reading '/lib/udev/rules.d/60-persistent-v4l.rules' as rules file
parse_file: reading '/lib/udev/rules.d/61-accelerometer.rules' as rules file
parse_file: reading '/lib/udev/rules.d/64-xorg-xkb.rules' as rules file
parse_file: reading '/lib/udev/rules.d/66-xorg-synaptics-quirks.rules' as rules file
parse_file: reading '/lib/udev/rules.d/69-cd-sensors.rules' as rules file
add_rule: IMPORT found builtin 'usb_id', replacing /lib/udev/rules.d/69-cd-sensors.rules:76
parse_file: reading '/lib/udev/rules.d/69-libmtp.rules' as rules file
parse_file: reading '/lib/udev/rules.d/69-xorg-vmmouse.rules' as rules file
parse_file: reading '/lib/udev/rules.d/69-xserver-xorg-input-wacom.rules' as rules file
parse_file: reading '/etc/udev/rules.d/70-persistent-cd.rules' as rules file
parse_file: reading '/etc/udev/rules.d/70-persistent-net.rules' as rules file
parse_file: reading '/lib/udev/rules.d/70-printers.rules' as rules file
parse_file: reading '/lib/udev/rules.d/70-udev-acl.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-cd-aliases-generator.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-net-description.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-persistent-net-generator.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-probe_mtd.rules' as rules file
parse_file: reading '/lib/udev/rules.d/75-tty-description.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-ericsson-mbm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-longcheer-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-nokia-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-pcmcia-device-blacklist.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-platform-serial-whitelist.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-qdl-device-blacklist.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-simtech-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-usb-device-blacklist.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-x22x-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-mm-zte-port-types.rules' as rules file
parse_file: reading '/lib/udev/rules.d/77-nm-olpc-mesh.rules' as rules file
parse_file: reading '/lib/udev/rules.d/78-graphics-card.rules' as rules file
parse_file: reading '/lib/udev/rules.d/78-sound-card.rules' as rules file
parse_file: reading '/lib/udev/rules.d/80-drivers.rules' as rules file
parse_file: reading '/lib/udev/rules.d/80-mm-candidate.rules' as rules file
parse_file: reading '/lib/udev/rules.d/80-udisks.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-brltty.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-hdparm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-hplj10xx.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-keyboard-configuration.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-regulatory.rules' as rules file
parse_file: reading '/lib/udev/rules.d/85-usbmuxd.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-alsa-restore.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-alsa-ucm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-libgpod.rules' as rules file
parse_file: reading '/lib/udev/rules.d/90-pulseaudio.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-cd-devices.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-keyboard-force-release.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-keymap.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-udev-late.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-dell.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-fujitsu.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-gateway.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-ibm.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-lenovo.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-battery-recall-toshiba.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-csr.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-hid.rules' as rules file
parse_file: reading '/lib/udev/rules.d/95-upower-wup.rules' as rules file
parse_file: reading '/lib/udev/rules.d/97-bluetooth-hid2hci.rules' as rules file
parse_file: reading '/etc/udev/rules.d/jj-video.rules' as rules file
udev_rules_new: rules use 259284 bytes tokens (21607 * 12 bytes), 37913 bytes buffer
udev_rules_new: temporary index used 67520 bytes (3376 * 20 bytes)
udev_device_new_from_syspath: device 0x215103e0 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1'
udev_device_new_from_syspath: device 0x21510758 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1'
udev_device_read_db: device 0x21510758 filled with db file data
udev_device_new_from_syspath: device 0x21510e10 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0'
udev_device_new_from_syspath: device 0x21511b10 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2/2-2'
udev_device_new_from_syspath: device 0x215132f8 has devpath '/devices/pci0000:00/0000:00:1d.0/usb2'
udev_device_new_from_syspath: device 0x21513650 has devpath '/devices/pci0000:00/0000:00:1d.0'
udev_device_new_from_syspath: device 0x21513980 has devpath '/devices/pci0000:00'
udev_rules_apply_to_event: GROUP 44 /lib/udev/rules.d/50-udev-default.rules:29
udev_rules_apply_to_event: IMPORT 'v4l_id /dev/video1' /lib/udev/rules.d/60-persistent-v4l.rules:7
udev_event_spawn: starting 'v4l_id /dev/video1'
spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_VERSION=2'
spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_PRODUCT=Logitech QuickCam Pro 3000'
spawn_read: 'v4l_id /dev/video1'(out) 'ID_V4L_CAPABILITIES=:capture:'
spawn_wait: 'v4l_id /dev/video1' [2609] exit with return code 0
udev_rules_apply_to_event: IMPORT builtin 'usb_id' /lib/udev/rules.d/60-persistent-v4l.rules:9
builtin_usb_id: /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0: if_class 10 protocol 0
udev_builtin_add_property: ID_VENDOR=046d
udev_builtin_add_property: ID_VENDOR_ENC=046d
udev_builtin_add_property: ID_VENDOR_ID=046d
udev_builtin_add_property: ID_MODEL=08b0
udev_builtin_add_property: ID_MODEL_ENC=08b0
udev_builtin_add_property: ID_MODEL_ID=08b0
udev_builtin_add_property: ID_REVISION=0002
udev_builtin_add_property: ID_SERIAL=046d_08b0_01402100A5000000
udev_builtin_add_property: ID_SERIAL_SHORT=01402100A5000000
udev_builtin_add_property: ID_TYPE=generic
udev_builtin_add_property: ID_BUS=usb
udev_builtin_add_property: ID_USB_INTERFACES=:0aff00:010100:010200:
udev_builtin_add_property: ID_USB_INTERFACE_NUM=00
udev_builtin_add_property: ID_USB_DRIVER=Philips webcam
udev_rules_apply_to_event: LINK 'v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0' /lib/udev/rules.d/60-persistent-v4l.rules:10
udev_rules_apply_to_event: IMPORT builtin 'path_id' /lib/udev/rules.d/60-persistent-v4l.rules:16
udev_builtin_add_property: ID_PATH=pci-0000:00:1d.0-usb-0:2:1.0
udev_builtin_add_property: ID_PATH_TAG=pci-0000_00_1d_0-usb-0_2_1_0
udev_rules_apply_to_event: LINK 'v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' /lib/udev/rules.d/60-persistent-v4l.rules:17
udev_rules_apply_to_event: RUN 'udev-acl --action=$env{ACTION} --device=$env{DEVNAME}' /lib/udev/rules.d/70-udev-acl.rules:74
udev_rules_apply_to_event: LINK 'webcam1' /etc/udev/rules.d/jj-video.rules:2
udev_event_execute_rules: no node name set, will use kernel supplied name 'video1'
udev_node_add: creating device node '/dev/video1', devnum=81:1, mode=0660, uid=0, gid=44
udev_node_mknod: preserve file '/dev/video1', because it has correct dev_t
udev_node_mknod: preserve permissions /dev/video1, 020660, uid=0, gid=44
node_symlink: preserve already existing symlink '/dev/char/81:1' to '../video1'
link_find_prioritized: found 'c81:2' claiming '/run/udev/links/v4l\x2fby-id\x2fusb-046d_08b0_01402100A5000000-video-index0'
udev_device_new_from_syspath: device 0x21516748 has devpath '/devices/pci0000:00/0000:00:1d.1/usb3/3-2/3-2:1.0/video4linux/video2'
udev_device_read_db: device 0x21516748 filled with db file data
link_find_prioritized: found 'c81:1' claiming '/run/udev/links/v4l\x2fby-id\x2fusb-046d_08b0_01402100A5000000-video-index0'
link_update: creating link '/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0' to '/dev/video1'
node_symlink: atomically replace '/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0'
link_find_prioritized: found 'c81:1' claiming '/run/udev/links/v4l\x2fby-path\x2fpci-0000:00:1d.0-usb-0:2:1.0-video-index0'
link_update: creating link '/dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' to '/dev/video1'
node_symlink: preserve already existing symlink '/dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0' to '../../video1'
link_find_prioritized: found 'c81:1' claiming '/run/udev/links/webcam1'
link_update: creating link '/dev/webcam1' to '/dev/video1'
node_symlink: preserve already existing symlink '/dev/webcam1' to 'video1'
udev_device_update_db: created db file '/run/udev/data/c81:1' for '/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1'
ACTION=add
COLORD_DEVICE=1
COLORD_KIND=camera
DEVLINKS=/dev/v4l/by-id/usb-046d_08b0_01402100A5000000-video-index0 /dev/v4l/by-path/pci-0000:00:1d.0-usb-0:2:1.0-video-index0 /dev/webcam1
DEVNAME=/dev/video1
DEVPATH=/devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2:1.0/video4linux/video1
ID_BUS=usb
ID_MODEL=08b0
ID_MODEL_ENC=08b0
ID_MODEL_ID=08b0
ID_PATH=pci-0000:00:1d.0-usb-0:2:1.0
ID_PATH_TAG=pci-0000_00_1d_0-usb-0_2_1_0
ID_REVISION=0002
ID_SERIAL=046d_08b0_01402100A5000000
ID_SERIAL_SHORT=01402100A5000000
ID_TYPE=generic
ID_USB_DRIVER=Philips webcam
ID_USB_INTERFACES=:0aff00:010100:010200:
ID_USB_INTERFACE_NUM=00
ID_V4L_CAPABILITIES=:capture:
ID_V4L_PRODUCT=Logitech QuickCam Pro 3000
ID_V4L_VERSION=2
ID_VENDOR=046d
ID_VENDOR_ENC=046d
ID_VENDOR_ID=046d
MAJOR=81
MINOR=1
SUBSYSTEM=video4linux
TAGS=:udev-acl:
UDEV_LOG=6
USEC_INITIALIZED=18213768
run: 'udev-acl --action=add --device=/dev/video1'
jjk@eee-old:~$ 

(und entsprechend für video2)

Es sieht für mich so aus, als würden meine Regeln gelesen, aber nicht respektiert. Was mache ich falsch?

Antworten:


10

Es sieht so aus, als hätten Sie zwei Probleme.

Das erste ist ein Bestellproblem. Beim Lesen der Manpage kernel.org auf udev wird Folgendes erwähnt:

Alle Regeldateien werden ... in lexikalischer Reihenfolge verarbeitet

Bedeutungsregeln werden in alphabetischer Reihenfolge verarbeitet. Die erste Regel, die für ein Gerät ausgelöst wird, erstellt die Gerätedatei. Es sieht so aus, als hätten Sie Ihre Regeldatei benannt jj-video.rules. Wenn Sie sich die von Ihnen bereitgestellte Ausgabe udevadm --debug testansehen, wird angezeigt, dass diese Datei LETZT von allen Regeldateien auf Ihrem System analysiert wird.

Versuchen Sie, Ihre Datei umzubenennen 00-jj-video.rules. Das sollte es an erster Stelle in der udev-Regelliste setzen und es vor den anderen Regeln auslösen lassen.

Das zweite Problem betrifft die Regeln selbst. Die Regeln lauten, dass Sie versuchen zu erstellen, /dev/webcam2wenn die Logitech QuickCam Pro 3000 angeschlossen ist und wenn der Kernel sie aktiviert /dev/video2. Nach dem, was Sie gesagt haben, möchten Sie nicht mit dem Gerätenamen übereinstimmen. Ein weiteres Problem ist, dass Sie in Ihrem ATTRS nicht immer die hexadezimale Notation verwenden.

Diese Regel sollte für die Logitech QuickCam Pro 3000 funktionieren, basierend auf den Informationen, die Sie in der Frage angegeben haben:

SUBSYSTEM=="video4linux", ATTRS{idVendor}=="0x046d", ATTRS{idProduct}=="0x08b0", SYMLINK+="webcam2"

Folgendes kann für die andere Webcam funktionieren. Ich kann nicht sicher sein, weil Sie nicht alle Informationen dazu angegeben haben:

SUBSYSTEM=="video4linux", SUBSYSTEMS=="usb", ATTRS{idVendor}=="0x1d6b", ATTRS{idProduct}=="0x0001", SYMLINK+="webcam1"

Das nützlichste Tutorial, das ich zum Schreiben von udev-Regeln gefunden habe, ist http://www.reactivated.net/writing_udev_rules.html .

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