Re: [REGRESSION/PATCH] acpi: blacklist win8 OSI for ASUS Zenbok Prime UX31A

From: Felipe Contreras
Date: Mon Jul 29 2013 - 16:23:03 EST

On Mon, Jul 29, 2013 at 3:17 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote:
> On Monday, July 29, 2013 02:20:58 PM Felipe Contreras wrote:
>> Since v3.7 the acpi backlight driver doesn't work at all on this machine
>> because presumably the ACPI code contains stub code when Windows 8 OSI is
>> reported.
>> The commit ea45ea7 (in v3.11-rc2) tried to fix this problem by using the intel
>> backlight driver, however, on this machine it turns the backlight completely
>> off when it reaches level 0%, after which the user might have a lot trouble
>> trying to bring it back.
>> This patch fixes both regressions by blacklisting the win8 OSI, so we are back
>> to v3.6 behavior, and it should remain that way until the intel backlight
>> driver is fixed.
> Well, it really is a workaround, so perhaps it would be fair to call it this
> way?

Maybe, but to me, and to most users, the important thing is that it
fixes a regression.

>> Since v3.7, users have been forced to fix the initial regression by modifying
>> the boot arguments [1].
>> [1]
>> Signed-off-by: Felipe Contreras <felipe.contreras@xxxxxxxxx>
> I don't really feel this is the right approach, but then I don't care enough
> to fight with you. :-)

It's not the right approach, I don't think I (or anybody) argued
otherwise, but unless the Intel driver is fixed before 3.11, it's the
only sane approach.

Felipe Contreras
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