RE: keyboard backlight max_brightness bug on Dell Latitude E6410

Gabriel M. Elder
2017-10-02T19:10:36Z

-------- Original Message --------
Subject: Re: keyboard backlight max_brightness bug on Dell Latitude
E6410
From: Pali Rohár <pali.rohar@gmail.com>
Date: Mon, October 02, 2017 8:15 am
To: gabriel@tekgnowsys.com
Cc: andy.shevchenko@gmail.com, gabriel@tekgnowsys.com,
gabriele.mzt@gmail.com, dvhart@infradead.org, andy@infradead.org,
platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org,
Mario.Limonciello@dell.com

On Monday 02 October 2017 13:06:46 Mario.Limonciello@dell.com wrote:
> > -----Original Message-----
> > From: Pali Rohár [mailto:pali.rohar@gmail.com]
> > Sent: Monday, October 2, 2017 6:53 AM
> > To: Andy Shevchenko <andy.shevchenko@gmail.com>
> > Cc: Gabriel M. Elder <gabriel@tekgnowsys.com>; Gabriele Mazzotta
> > <gabriele.mzt@gmail.com>; Limonciello, Mario <Mario_Limonciello@Dell.com>;
> > Darren Hart <dvhart@infradead.org>; Andy Shevchenko <andy@infradead.org>;
> > platform-driver-x86@vger.kernel.org; linux-kernel@vger.kernel.org
> > Subject: Re: keyboard backlight max_brightness bug on Dell Latitude E6410
> >
> > On Friday 29 September 2017 18:19:59 Andy Shevchenko wrote:
> > > >> FYI, latest update and info relating to
> > > >> https://bugzilla.kernel.org/show_bug.cgi?id=196913
> > >
> > > Quick solution is to apply DMI to that.
> >
> > It is only the Dell Latitude E6410 affected?
> >
> > Mario, do you have any information about that API from Dell?
> >
> > --
> > Pali Rohár
> > pali.rohar@gmail.com
>
> Pali,
>
> I believe this particular API shouldn't have changed over generations, so it's
> likely something that needs to be quirked for that generation.
> I haven't had a chance to check on this yet in detail though.
> For now could you guys quirk this one and if I find out there was something
> more systemic we can undo the quirk and do something more broad.
>
> Thanks,

Ok! Gabriel, can you provide us your DMI information about your machine?

They are included in following files:
/sys/class/dmi/id/sys_vendor
/sys/class/dmi/id/product_name

Beware that they may contain whitespace characters and it is important.

--
Pali Rohár
pali.rohar@gmail.com

-------------------------------------------------------------------------------
# cat -v /sys/class/dmi/id/sys_vendor
Dell Inc.
# cat -v /sys/class/dmi/id/product_name
Latitude E6410
# cat -v /sys/class/dmi/id/sys_vendor | hexdump
0000000 6544 6c6c 4920 636e 0a2e
000000a
# cat -v /sys/class/dmi/id/product_name | hexdump
0000000 614c 6974 7574 6564 4520 3436 3031 000a
000000f

Also updated https://bugzilla.kernel.org/show_bug.cgi?id=196913 with
this info

- Gabriel
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