[mythtv-users] "Moving" /dev nodes

[Sam Hathaway]

On Oct 7, 2006, at 7:33 PM, lkidd at bigpond.net.au wrote:

> Hi Everyone,
> Has anyone encountered the following ?
> I have a Myth FE/BE system running FC5 with a Dvico Dual Digital  
> tuner and a Hauppage PVR-350. When I reboot the system, the  
> Hauppage card moves from /dev/video0 to /dev/video1. If I reboot  
> again, it will move back. It doesn't happen every time but enough  
> to be a pain in the butt. Is there anyway to lock the card to a  
> certain /dev node ?
> Thanks...
> LK

You can accomplish this by writing udev rules for the two devices.  
Take a look at <http://reactivated.net/writing_udev_rules.html>. Here  
are my udev rules, for persistent naming of my bttv and cx8800 cards.

sam at spider:~$ cat /etc/udev/rules.d/video4linux.rules
KERNEL=="radio[0-9]*" SYSFS{device}=="0x036e" SYSFS{vendor}=="0x109e"  
SYMLINK="bttv-radio"
KERNEL=="vbi[0-9]*"   SYSFS{device}=="0x036e" SYSFS{vendor}=="0x109e"  
SYMLINK="bttv-vbi"
KERNEL=="video[0-9]*" SYSFS{device}=="0x036e" SYSFS{vendor}=="0x109e"  
SYMLINK="bttv-video"

KERNEL=="radio[0-9]*" SYSFS{device}=="0x8800" SYSFS{vendor}=="0x14f1"  
SYMLINK="cx8800-radio"
KERNEL=="vbi[0-9]*"   SYSFS{device}=="0x8800" SYSFS{vendor}=="0x14f1"  
SYMLINK="cx8800-vbi"
KERNEL=="video[0-9]*" SYSFS{device}=="0x8800" SYSFS{vendor}=="0x14f1"  
SYMLINK="cx8800-video"

I used the "device" and "vendor" attributes, which I got from running:
	udevinfo -a -p $(udevinfo -q path -n /dev/video0)

Hope this helps.
-sam