[PATCH AUTOSEL 4.9 03/13] ALSA: hda: Keep the controller initialization even if no codecs found

[Sasha Levin]

On Fri, Apr 24, 2020 at 02:45:55PM +0200, Takashi Iwai wrote:
>On Fri, 24 Apr 2020 14:24:36 +0200,
>Sasha Levin wrote:
>>
>> From: Takashi Iwai <tiwai at suse.de>
>>
>> [ Upstream commit 9479e75fca370a5220784f7596bf598c4dad0b9b ]
>>
>> Currently, when the HD-audio controller driver doesn't detect any
>> codecs, it tries to abort the probe.  But this abort happens at the
>> delayed probe, i.e. the primary probe call already returned success,
>> hence the driver is never unbound until user does so explicitly.
>> As a result, it may leave the HD-audio device in the running state
>> without the runtime PM.  More badly, if the device is a HD-audio bus
>> that is tied with a GPU, GPU cannot reach to the full power down and
>> consumes unnecessarily much power.
>>
>> This patch changes the logic after no-codec situation; it continues
>> probing without the further codec initialization but keep the
>> controller driver running normally.
>>
>> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207043
>> Tested-by: Roy Spliet <nouveau at spliet.org>
>> Link: https://lore.kernel.org/r/20200413082034.25166-5-tiwai@suse.de
>> Signed-off-by: Takashi Iwai <tiwai at suse.de>
>> Signed-off-by: Sasha Levin <sashal at kernel.org>
>
>Applying this without other commits isn't recommended, especially for
>the older branches.  Maybe OK up from 4.19, but I'd avoid applying for
>the older.

Okay, I've dropped it from branches older than 4.19. Thanks!

-- 
Thanks,
Sasha