Re: i915 backlight

From: Josep Lladonosa
Date: Fri Aug 02 2013 - 16:03:12 EST


With this setup, something has happened: in xorg, when screen goes to
screensaver and after, enters into Standby mode, when I press a key,
it keeps black and, to recover screen, I have to adjust brightness
manually (by increasing), as if it didn't remember previous value to
standby mode.

This was something that before didn't happen.


On 2 August 2013 20:58, Felipe Contreras <felipe.contreras@xxxxxxxxx> wrote:
> On Fri, Aug 2, 2013 at 9:03 AM, Rafael J. Wysocki <rjw@xxxxxxx> 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@xxxxxxxxx> 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*.
> 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

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