[Intel-gfx] i915 backlight

[Felipe Contreras]

On Fri, Aug 2, 2013 at 9:03 AM, Rafael J. Wysocki <rjw at sisk.pl> wrote:
> On Friday, August 02, 2013 01:48:37 AM Felipe Contreras wrote:
>> On Fri, Aug 2, 2013 at 1:25 AM, Josep Lladonosa <jlladono at gmail.com> wrote:
>> > Hello,
>> >
>> > I am using a Lenovo Edge E530 and, with kernel 3.11.0-rc3, I had to
>> > change to this parameter to the kernel boot:
>> >
>> >
>> > GRUB_CMDLINE_LINUX="acpi_osi=\"!Windows 2012\""
>>
>> I think it's pretty obvious that for the time being we need to
>> blacklist a ton of machines so they boot without this OSI. In fact, in
>> might make sense to simply remove the OSI completely for all machines
>> (for now).
>
> That would have made sense 6 months ago, but not today.

Today, like 6 months ago these machines remain broken, and it will be
the same tomorrow, presumably on v3.11, and at least v3.12 as well.

> The reason is that you don't really know what's affected by that and I'm
> pretty sure it's not only backlight.

I haven't heard a single comment that says acpi_osi="!Windows 2012"
breaks other things. OTOH everybody is saying it fixes the backlight
problem (if indeed it's the same problem).

Are you claiming that those users are wrong?

> So no, we won't do that.

Yeah, because that would fix the backlight problems, not tomorrow, or
several months from now, *today*. Geez, who would want that?

Here is the patch to fix the problem, *today*.

https://bugzilla.kernel.org/show_bug.cgi?id=60682

This is what we should do:

1) Improve that blacklist list
2) Fix the Intel driver issues
3) Enable your patch that uses the Intel driver instead
4) Remove that patch

Anything else is not be good for the users.

-- 
Felipe Contreras