Re: [RFC] EDAC and the sysfs

[Kay Sievers <kay.sievers@vrfy.org>]

On Thu, Nov 17, 2005 at 09:18:56AM -0800, Greg KH wrote:
> On Thu, Nov 17, 2005 at 09:20:53AM -0800, Doug Thompson wrote:
> > > But you can just probably use a udev rule to
> > > initialize your things
> > > properly, that's what all of the distros are now
> > > using.
> > 
> > Ok. That's another area for me to research. edac does
> > not have any /dev/ entries, just the files and
> > controls previous mentioned. 
> > 
> > So, from your comment then, udev has some mechanism to
> > set controls in sysfs?
> 
> udev gets called whenever you add a kobject to the system.  You can then
> do whatever you want in udev when this happens.  As an example, on one
> distro, when a bluetooth device is created by the kernel, a bluetooth
> startup script is run by udev.

We do things like this:
  ACTION=="add", SUBSYSTEM="scsi", SYSFS{type}=="1", RUN+="/bin/sh -c 'echo 900 > /sys/$DEVPATH/timeout'"

There are only very few users now, that set values in sysfs. If that is
a common need to change values with udev rules we may integrate that into
udev itself, instead of calling a shell, but that works fine so far.

Kay