Re: Possible regression 3.8.7 -> 3.9 with Dell touchpad

["Tibor Billes" <tbilles@gmx.com>]

From: Dmitry Torokhov Sent: 05/10/13 12:54 AM
> 
> On Thu, May 09, 2013 at 10:59:58PM +0200, Tibor Billes wrote:
> > Hi,
> > 
> > I found that after upgrading my kernel from 3.8.7 to 3.9 my touchpad only
> > works partly. By that I mean I can use the touchpad to move the cursor
> > around, but I cannot click with it by tapping.
> 
> Is the touchpad recognized as ALPS or PS/2 mouse in 3.8.7? Also, can you
> check that touchpad tapping is enabled in your desktop environment?

In 3.8.7 it is recognized as PS/2 mouse and the desktop environment doesn't even offer any touchpad settings. In 3.9.1 the touchpad is recognized as 'AlpsPS/2 ALPS DualPoint TouchPad' and yes, the touchpad settings appeared, and yes, clicking was disabled. Enabled it, works like a charm :)

So what happened is that the 3.8.7 kernel did not recognize my touchpad, so it fell back to PS/2 which worked well for me. The 3.9 kernel recongizes my touchpad correctly because Kevin updated the driver, and my system started using a different configuration as it knew it was a touchpad and not some PS/2 device. Am I right? I recall looking for touchpad settings in one of the 3.8.x kernels and I didn't find any so I didn't bother looking for it again in 3.9...

In this case I'm sorry for the false report, and thank you guys for the driver update :)

> Thanks.
> 
> > My machine is a Dell
> > Latitude E5530. Since it is 100% reproducible on my machine, I bisected it,
> > and found this commit:
> > 
> > commit 1302bac33d9e88cd43e482191a806998f3ed43cc
> > Author: Kevin Cernekee <cernekee@gmail.com>
> > Date:   Wed Feb 13 22:27:08 2013 -0800
> > 
> >    Input: ALPS - add support for "Rushmore" touchpads
> >    
> >    Rushmore touchpads are found on Dell E6230/E6430/E6530.  They use the V3
> >    protocol with slightly tweaked init sequences and report formats.
> >    
> >    The E7 report is 73 03 0a, and the EC report is 88 08 1d
> >    
> >    Credits: Emmanuel Thome reported the MT bitmap changes.
> >    
> >    Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
> >    Tested-by: Dave Turvene <dturvene@dahetral.com>
> >    Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
> > 
> > I did the bisection between 3.8.7 and 3.9, but also tried 3.9.1, it is bad
> > too. I also tried reverting that commit to make sure that it really is
> > what made my touchpad not working. The revert did fix my problem.
> > 
> > That's all I gathered so far, but I'd be happy to help further in any way
> > I can, just let me know.
> > 
> > Thanks,
> > Tibor
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-input" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> 
> -- 
> Dmitry
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html