udev bug? (I don't think so)

udev bug? (I don't think so)

[Ian Pilcher]

There's a sporadic discussion over on the pilot-link mailing lists about
writing udev rules for Palm Treos (and similar multi-port devices).

When one of these devices is plugged in, the visor driver creates two
USB serial devices; a udev rule which matches the SYSFS{idVendor} and
SYSFS{idProduct} will match both serial devices, and /dev/pilot will end
up linked to whichever USB serial port is processed *last*.  The last
serial port processed is not necessarily the device with the higher
kernel number.

Several people on the pilot-link list have stated that this is a udev
bug, but I don't agree.  AFAIK, udev provides no assurance as to the
order in which events are processed -- regardless of the order in which
they are generated.

Am I correct?

Thanks!

-- 
====================================
Ian Pilcher                                        i.pilcher@comcast.net
====================================



-------------------------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid\x120709&bid&3057&dat\x121642
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: udev bug? (I don't think so)

[Greg KH]

On Fri, Jul 14, 2006 at 02:12:35PM -0500, Ian Pilcher wrote:
> There's a sporadic discussion over on the pilot-link mailing lists about
> writing udev rules for Palm Treos (and similar multi-port devices).
> 
> When one of these devices is plugged in, the visor driver creates two
> USB serial devices; a udev rule which matches the SYSFS{idVendor} and
> SYSFS{idProduct} will match both serial devices, and /dev/pilot will end
> up linked to whichever USB serial port is processed *last*.  The last
> serial port processed is not necessarily the device with the higher
> kernel number.
> 
> Several people on the pilot-link list have stated that this is a udev
> bug, but I don't agree.  AFAIK, udev provides no assurance as to the
> order in which events are processed -- regardless of the order in which
> they are generated.
> 
> Am I correct?

Yes you are.  See the archives of this list for how difficult it is to
write a generic rule for the visor/clie/palm devices that will always
work properly.

thanks,

greg k-h


-------------------------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid\x120709&bid&3057&dat\x121642
_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel

Re: udev bug? (I don't think so)

[Scott James Remnant]

[-- Attachment #1.1: Type: text/plain, Size: 688 bytes --]

On Fri, 2006-07-14 at 14:12 -0500, Ian Pilcher wrote:

> Several people on the pilot-link list have stated that this is a udev
> bug, but I don't agree.  AFAIK, udev provides no assurance as to the
> order in which events are processed -- regardless of the order in which
> they are generated.
> 
I've expressed (via the equivalent Ubuntu bugs for this) that the right
thing for the GNOME Pilot stuff to do is to use HAL to find the Palm
Pilots and then pick the serial port that it knows is correct.

That way no symlink is required, and the user can be presented with a
"humanised" list of connected Pilot-like devices.

Scott
-- 
Scott James Remnant
scott@ubuntu.com

[-- Attachment #1.2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 191 bytes --]

[-- Attachment #2: Type: text/plain, Size: 375 bytes --]


-------------------------------------------------------------------------
Using Tomcat but need to do more? Need to support web services, security?
Get stuff done quickly with pre-integrated technology to make your job easier
Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo
http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642

[-- Attachment #3: Type: text/plain, Size: 226 bytes --]

_______________________________________________
Linux-hotplug-devel mailing list  http://linux-hotplug.sourceforge.net
Linux-hotplug-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linux-hotplug-devel