Re: [PATCH] ALSA: hda: Enable runtime PM when codec probe fails

[Kai-Heng Feng <kai.heng.feng@canonical.com>]

On Mon, Dec 14, 2020 at 08:58, Takashi Iwai <tiwai@suse.de> wrote:
> On Mon, 14 Dec 2020 07:06:20 +0100,
> Kai-Heng Feng wrote:
>> 
>>  When codec probe fails, it doesn't enable runtime suspend, and can
>>  prevent graphics card from getting powered down:
>>  [    4.280991] snd_hda_intel 0000:01:00.1: no codecs initialized
>> 
>>  $ cat /sys/bus/pci/devices/0000:01:00.1/power/runtime_status
>>  active
>> 
>>  So enable runtime PM when codec probe fails, to let graphics card be
>>  able to runtime suspend again.
> 
> Well, the runtime status is also active if the driver isn't probed at
> all.  In that sense, keeping the status active at the driver load
> failure is rather consistent, IMO.  If the driver fails or unloaded,
> it should restore the status as if it were beforehand.

Ok, let me find a better way to handle it.

Kai-Heng

> 
> 
> thanks,
> 
> Takashi
> 
>> 
>>  Merge azx_probe_continue() into azx_probe() and just let probe fail 
>> for
>>  this case could be a better approach. However that's a much bigger 
>> task
>>  so let's settle with a quirk workaround.
>> 
>>  BugLink: <https://bugs.launchpad.net/bugs/1907212>
>>  Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com 
>> <mailto:kai.heng.feng@canonical.com>>
>>  ---
>>   sound/pci/hda/hda_intel.c | 3 ++-
>>   1 file changed, 2 insertions(+), 1 deletion(-)
>> 
>>  diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
>>  index 6852668f1bcb..3fd920069268 100644
>>  --- a/sound/pci/hda/hda_intel.c
>>  +++ b/sound/pci/hda/hda_intel.c
>>  @@ -2328,7 +2328,7 @@ static int azx_probe_continue(struct azx 
>> *chip)
>>   	if (bus->codec_mask) {
>>   		err = azx_probe_codecs(chip, azx_max_codecs[chip->driver_type]);
>>   		if (err < 0)
>>  -			goto out_free;
>>  +			goto out_enable_rpm;
>>   	}
>> 
>>   #ifdef CONFIG_SND_HDA_PATCH_LOADER
>>  @@ -2360,6 +2360,7 @@ static int azx_probe_continue(struct azx 
>> *chip)
>> 
>>   	set_default_power_save(chip);
>> 
>>  +out_enable_rpm:
>>   	if (azx_has_pm_runtime(chip)) {
>>   		pm_runtime_use_autosuspend(&pci->dev);
>>   		pm_runtime_allow(&pci->dev);
>>  --
>>  2.29.2
>>