Slackware 11, udev, and card readers

I spent the better part of last night trying to convert my udev rules that I wrote for Slackware 10.2 to work with the new udev in Slackware 11/-current. The udev developers were "kind" enough to make some significant changes to the way that rules are written. Hopefully that has stabilized now. At any rate, here are the rules that I have for my 8-in-1 card reader and my USB drive, using the huge26.s kernel:

# Card reader
BUS=="scsi", ID=="*:0", SYSFS{model}=="STORAGE DEVICE ", NAME="compactflash", OPTIONS+="all_partitions"
BUS=="scsi", ID=="*:2", SYSFS{model}=="STORAGE DEVICE ", NAME="securedigital", OPTIONS+="all_partitions"

# USB drive
BUS=="scsi", KERNEL=="sd*", SYSFS{vendor}=="OTi", SYSFS{model}=="Flash Disk", NAME="%k", SYMLINK+="usbdrive"

Now some brief explanation. I only use the compact flash and secure digital slots on my reader, so those are the only rules I set up. The kernel treats each slot as if it were a SCSI drive. I obtained the information on the SCSI ID and model name by using "udevinfo -a -p /sys/block/sda" (sdc for the secure digital slot). The NAME creates a /dev/ node. The OPTIONS makes sure it creates /dev/compactflash[1-15] since the data is actually on the first "partition" for some reason.

Re: the USB drive, in the old udev I just looked for the vendor and model and then used NAME to create the node. That didn't work with the new udev. Instead of basically creating what would normally be /dev/sde, it created /dev/sg4 which wouldn't allow me to mount the drive. So now /dev/sde is still created but with a symbolic link pointing to it at /dev/usbdrive.

True, I could just add /dev/sde to my fstab, but if I would add or remove SCSI devices (or some future udev change would set things up in a different order), it would break. With that rule, /dev/usbdrive will always point to the right place.

I hope somebody might find this useful. Hours of Googling turned up only older rules for older versions of udev. Check out Writing udev Rules for more information. That page is up-to-date for the latest udev.

I should add that even though the huge26.s kernel does not automatically search for multiple LUNs, adding this line to lilo.conf allows things to work anyway:

append="max_scsi_luns=5"

I didn't need to make a rule for my usb pen drive - it works fine with whatever the default rule is. That's with udev 097 in slack-current.

Originally Posted by dive I didn't need to make a rule for my usb pen drive - it works fine with whatever the default rule is. That's with udev 097 in slack-current.

It worked fine with mine too. udev created /dev/sde when I inserted it and I would have been good to go. The only reason I have the rule now is if I add or remove SCSI devices, it would no longer be /dev/sde. For example if I unplugged my card reader, udev would put it as /dev/sda which would then break my fstab entry.

Ah mine was made sda1 and I have no other usb/scsi devices. I guess that my situation is simpler.