Re: Udev. Problems with ordering hardware using /dev/video

On Tue, Jul 31, 2007 at 19:47:51 +0200, Nigel Henry wrote:
I've managed to resolve most of my problems on my own, but Udev has beaten me.

Sarge is not a problem, as it's using the 2.4.27, or 2.6.8 kernel, and Udev is
not in the equation. Etch has a 2.6.8, and a 2.6.17 kernel, and Lenny has a
2.6.11, and a 2.6.17 kernel. The problem is with the 2.6.17 kernel that uses
Udev.

My TV card was set as /dev/video0, and some time later the webcam was set
as /dev/video1. this works fine with the pre 2.6.17 kernels (no Udev), and
the TV card consistently is /dev/video0, and the webcam /dev/video1. Booting
with the 2.6.17 kernel is a different scenario. Very hit and miss. Sometimes
I boot up and starting Xawtv, I get the TV /dev/video0. Othertimes I bootup
and start Xawtv, and get my webcam /dev/video1.

This flip-flopping is, AFAIK, more the fault of the newer kernel then
the fault of udev. If the kernel would always load the modules in the
same order then udev would probably assign the device nodes in a
consistent manner.

I've worked with ordering my soundcards, and the lines are quite simple, and
have seen that something similar is possible with Udev, although the lines a
re a bit more complex. Could someone give me a couple of lines so that my TV
card is always /dev/video0, and the webcam is always /dev/video1?

Any help gratefully appreciated for fixing this annoying problem.

Post the output of:

udevinfo -a -p $(udevinfo -q path -n /dev/video0)

udevinfo -a -p $(udevinfo -q path -n /dev/video1)

(Only the blocks that have things like "ATTRS{model}" or "ATTRS{vendor}"
are important.)

--
Regards, | http://users.icfo.es/Florian.Kulzer
Florian |


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