mirror of https://gitee.com/openkylin/linux.git
539a7555b3
A number of V4L drivers have a mod param to specify their preferred minors. This is because it is often desirable for applications to have a static /dev name for a particular device. However, using minors has several disadvantages: 1) the requested minor may already be taken 2) using a mod param is driver specific 3) it requires every driver to add a param 4) requires configuration by hand This patch introduces an "index" attribute that when combined with udev rules can create static device paths like this: /dev/v4l/by-path/pci-0000\:00\:1d.2-usb-0\:1\:1.0-video0 /dev/v4l/by-path/pci-0000\:00\:1d.2-usb-0\:1\:1.0-video1 /dev/v4l/by-path/pci-0000\:00\:1d.2-usb-0\:1\:1.0-video2 $ ls -la /dev/v4l/by-path/pci-0000\:00\:1d.2-usb-0\:1\:1.0-video0 lrwxrwxrwx 1 root root 12 2008-04-28 00:02 /dev/v4l/by-path/pci-0000:00:1d.2-usb-0:1:1.0-video0 -> ../../video1 These paths are steady across reboots and should be resistant to rearranging across Kernel versions. video_register_device_index is available to drivers to request a specific index number. Signed-off-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Kees Cook <kees@outflux.net> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> |
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| acpi | ||
| asm-alpha | ||
| asm-arm | ||
| asm-avr32 | ||
| asm-blackfin | ||
| asm-cris | ||
| asm-frv | ||
| asm-generic | ||
| asm-h8300 | ||
| asm-ia64 | ||
| asm-m32r | ||
| asm-m68k | ||
| asm-m68knommu | ||
| asm-mips | ||
| asm-mn10300 | ||
| asm-parisc | ||
| asm-powerpc | ||
| asm-s390 | ||
| asm-sh | ||
| asm-sparc | ||
| asm-sparc64 | ||
| asm-um | ||
| asm-v850 | ||
| asm-x86 | ||
| asm-xtensa | ||
| crypto | ||
| drm | ||
| keys | ||
| linux | ||
| math-emu | ||
| media | ||
| mtd | ||
| net | ||
| pcmcia | ||
| rdma | ||
| rxrpc | ||
| scsi | ||
| sound | ||
| video | ||
| xen | ||
| Kbuild | ||