Re: [PATCH] acpi-video: Put the Acer Aspire V5-471G on the use_native_backlight dmi list

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 05/01/2014 10:10 PM, Rafael J. Wysocki wrote:
> On Thursday, May 01, 2014 12:38:28 PM Hans de Goede wrote:
>> Hi,
>>
>> On 04/30/2014 09:52 PM, Rafael J. Wysocki wrote:
>>> On Wednesday, April 30, 2014 03:37:21 PM Hans de Goede wrote:
>>>> This fixes the backlight control not working.
>>>>
>>>> Cc: stable@vger.kernel.org
>>>> Reported-and-tested-by: Vincent Gerris <vgerris@gmail.com>
>>>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>>>
>>> Sorry, this conflicts with commit 170269a9d3c0 (ACPI / video: Default to using
>>> native backlight control on Windows 8 systems) in linux-next, so I'm not going
>>> to apply it.
>>
>> I strongly disagree, rejecting bug-fixes which conflict with more rigorous
>> (and dangerous) fixes -next, purely because the conflict with something -next
>> is not a good reason. TBH I find it a complete non reason to reject these fixes.
>>
>>> If you wanted to have this stuff in 3.15, there was a plenty of time to submit
>>> it earlier.
>>
>> Heh, that assumes I was aware of this particular model needing this quirk earlier,
>> while I actually got the first report of it not working from Vincent on April 26th,
>> and got confirmation that the quirk fixes it on April 29th. I would say that 1 day
>> turn around time between getting the confirmation and sending the patch is not bad
>> at all.
>>
>> I really believe it is important to get the quirk for this model (and others) into
>> 3.15, here us my decision tree leading to this:
>>
>> -Do we want to fix these brightness issues -> Yes
>> -Do we expect our users to wait for 6 months for an upstream fix + many more months
>>  for the fixed kernel to hit distros -> No
>> -So we want to backport these fixes to stable -> Yes
>> -Is the proposed fix for 3.16 acceptable for stable -> No (too high change of
>>  regressions)
> 
> OK, this is a good argument.
> 
>> Conclusion: we want quirks for models known to need quirks added to 3.15 and
>> backported to the various stable series.
>>
>> I actually want to go as far as to claim that once 3.15 is released we will want
>> to add quirks to 3.15.x, breaking the every fix must be upstream rule for the stable
>> series. But lets safe that discussion for later.
> 
> Well, there's a way out of this.  Instead of doing commit 170269a9d3c0 as is, we
> can just switch the default without removing the blacklist just yet.  And remove
> the blacklist one we are reasonably confident that the new default actually works.
> 
> In which case I'd go for your original series (along with the RFC moving stuff
> out of blacklist.c to the video.c blacklist) with a replacement of commit
> 170269a9d3c0 that will simply flip the default.
> 
> Does this make sense to you?

Yes that seems like a good solution, thanks!

I'll rebase and resend my RFC for moving the models from blacklist.c to video.c as non
RFC.

Who is going to do the only flip the default version of 170269a9d3c0 ?

Regards,

Hans