udev problems - missing cdrom, and lircd instead of lirc/0

Message

dsegel · Post by **dsegel** » Sun Feb 26, 2006 6:01 am

I somehow managed to muck things up on one of my systems, and I don't know how to fix it.

First, I have no device entry for my CD/DVD drive. There is no /dev/cdrom, /dev/dvd, or /dev/cdroms/0. My dvd drive is /dev/hdd. I tried making a symlink to it, but it disappears when I reboot. How do I fix this?

Second, lirc keeps coming back as /dev/lircd even though it's supposed to be /dev/lirc/0. I once got the /dev/lirc/0 device created by unloading/reloading the lirc_i2c module, but it disapeared on reboot and now I can't make it come back at all.

udev version is 079-r1

lirc is 0.8.0

Anything else I can provide to help figure this out?

jomen · Post by **jomen** » Sun Feb 26, 2006 9:10 am

Have a look at the file /etc/udev/cdsymlinks.conf - and uncomment the appropriate lines to have /dev/hdd also show up as /dev/cdrom ...
I don't have lirc - but: you could change some config-file to reflect the new name for the device-file?
Or write a custom udev-rule to still get the old one...

dsegel · Post by **dsegel** » Sun Feb 26, 2006 3:35 pm

I made a line that says 'OUTPUT="CD DVD"' and rebooted but the device is still missing. I even tried running the cdsymlinks.sh script manually and it correctly identifies "cdrom dvd" if I give it the proper device name (hdd).

Any other ideas? I'll keep plugging away at it myself too.

jomen · Post by **jomen** » Sun Feb 26, 2006 4:10 pm

I looked at the script - it takes its values from /proc/sys/dev/cdrom/info
Depending on what is there - and compared with what you give in the config-file - it will create the links.
I did just nothing but to uncomment the line - maybe that is what you should do too?
my line reads:
OUTPUT="CD CDRW DVD DVDRW DVDRAM"
...basically just everything imaginable...some of which are created and some are not - because the drive is not an DVDRAM for instance

dsegel · Post by **dsegel** » Sun Feb 26, 2006 4:34 pm

I don't think it actually creates the links, it just outputs what they should be for a given device. For example, if you run:

./cdsymlinks.dh hdd

it will output (in my case) 'cdrom dvd'. I presume some other part of udev then takes this and creates the actual links, but that's not working for me.

jomen · Post by **jomen** » Sun Feb 26, 2006 5:23 pm

...no, it doesn't...
In the top few lines there is a usage description - it is supposed to be called by udev as it goes over the devices - which then creates the links.
...thats what I thought it was working anyway - but if I can read but not understand the file - which is quite possible - it seems that it does nothing, because it is not called anywhere (that is to say - I haven't found anything)
Instead I have these lines in /etc/udev/rules.d/50-udev-rules - which obviously take care of creating the symlinks without the cdsymlinks.sh

Code: Select all

# cdrom symlinks and other good cdrom naming
BUS=="ide",     KERNEL=="hd[a-z]", ACTION=="add", IMPORT="/sbin/cdrom_id --export $tempnode"
BUS=="scsi",    KERNEL="sr[0-9]*", ACTION=="add", IMPORT="/sbin/cdrom_id --export $tempnode"
BUS=="scsi",    KERNEL="scd[a-z]", ACTION=="add", IMPORT="/sbin/cdrom_id --export $tempnode"
BUS=="scsi",    KERNEL="sg[0-9]*", ACTION=="add", DRIVER=="sr", GROUP="cdrom"
ENV{ID_CDROM}=="?*",            SYMLINK+="cdrom%e", GROUP="cdrom"
ENV{ID_CDROM_CD_RW}=="?*",      SYMLINK+="cdrw%e"
ENV{ID_CDROM_DVD}=="?*",        SYMLINK+="dvd%e"
ENV{ID_CDROM_DVD_R}=="?*",      SYMLINK+="dvdrw%e"

maybe that helps?

dsegel · Post by **dsegel** » Sun Feb 26, 2006 8:45 pm

Well, I got the cdrom and dvd entries by adding these lines to a new rules file:

KERNEL="hdd", SYMLINK="dvd"
KERNEL="hdd", SYMLINK="cdrom"

I think they worked before because of leftover devcie entries from when I was using devfs, and removing them (accidently) was what messed things up. Whatever the reason, that part works now.

I also fixed the missing lirc/0 device by just loading the lirc_i2c module explicitly at boot time. It was being loaded by something else previously, and that wasn't creating the devices properly.

Thanks for the help - I've learned something new about udev, so I guess this wasn't a total waste of time.

linuxtuxhellsinki · Post by **linuxtuxhellsinki** » Sun Feb 26, 2006 9:38 pm

I've also some problems with lirc and in lirc.org there was something about that you've to make udev-rules by yourself (or copy them from lirc source's contrib/ directory). But now I've that file made automatically, so maybe gentoo-devs fixed it ?

Code: Select all

drake ~ # cat /etc/udev/rules.d/10-lirc.rules
KERNEL="lirc[0-9]*",    NAME="lirc/%n"