[PATCH 2/2] ALSA: hda/cs8409: Prevent pops and clicks during reboot

[Vitaly Rodionov]

On 26/08/2021 1:20 pm, Takashi Iwai wrote:
> On Thu, 26 Aug 2021 13:49:32 +0200,
> Vitaly Rodionov wrote:
>> On 26/08/2021 11:49 am, Takashi Iwai wrote:
>>> On Thu, 26 Aug 2021 08:03:45 +0200,
>>> Takashi Iwai wrote:
>>>> On Wed, 25 Aug 2021 20:04:05 +0200,
>>>> Vitaly Rodionov wrote:
>>>>> Actually when codec is suspended and we do reboot from UI, then sometimes we
>>>>> see suspend() calls in kernel log and no pops, but sometimes
>>>>>
>>>>> we still have no suspend() on reboot and we hear pops. But when we do reboot
>>>>> from command line: > sudo reboot  then we always have pops and no suspend()
>>>>> called.
>>>>>
>>>>> Then we have added extra logging and we can see that on reboot codec somehow
>>>>> getting resume() call and we run jack detect on resume that causing pops.
>>>> Hm, it's interesting who triggers the runtime resume.
>>>>
>>>>> We were thinking about possible solution for that and we would propose some
>>>>> changes in generic code hda_bind.c:
>>>>>
>>>>> static void hda_codec_driver_shutdown(struct device *dev) { +   if (codec->
>>>>> patch_ops.suspend) +      codec->patch_ops.suspend(codec);
>>>>> snd_hda_codec_shutdown(dev_to_hda_codec(dev)); +  hda_codec_driver_remove
>>>>> (dev_to_hda_codec(dev)); }
>>>> Sorry, it's no-no.  The suspend can't be called unconditionally, and
>>>> the driver unbind must not be called in the callback itself.
>>>>
>>>> Does the patch below work instead?
>>> Sorry there was a typo.  A bit more revised patch is below.
>>>
>>>
>>> Takashi
>>>
>>> --- a/sound/pci/hda/hda_intel.c
>>> +++ b/sound/pci/hda/hda_intel.c
>>> @@ -1383,14 +1383,17 @@ static void azx_free(struct azx *chip)
>>>    	hda->freed = 1;
>>>    }
>>>    -static int azx_dev_disconnect(struct snd_device *device)
>>> +static void __azx_disconnect(struct azx *chip)
>>>    {
>>> -	struct azx *chip = device->device_data;
>>>    	struct hdac_bus *bus = azx_bus(chip);
>>>      	chip->bus.shutdown = 1;
>>>    	cancel_work_sync(&bus->unsol_work);
>>> +}
>>>    +static int azx_dev_disconnect(struct snd_device *device)
>>> +{
>>> +	__azx_disconnect(device->device_data);
>>>    	return 0;
>>>    }
>>>    @@ -2356,8 +2359,10 @@ static void azx_shutdown(struct pci_dev
>>> *pci)
>>>    	if (!card)
>>>    		return;
>>>    	chip = card->private_data;
>>> -	if (chip && chip->running)
>>> +	if (chip && chip->running) {
>>> +		__azx_disconnect(chip);
>>>    		azx_shutdown_chip(chip);
>>> +	}
>>>    }
>>>      /* PCI IDs */
>> Hi Takashi,
>>
>> Applied fix and tested on dolphin HW. Issue still there, here is
>> captured screen on reboot from command line:
>>
>> reboot capture
>>
>> Reboot from UI works differently, no resume() call in this case.
> Thanks for quick testing.
>
> After reconsideration, I believe we can even take a simpler path.
> Use pm_runtime_force_suspend(), and keep suspended by
> pm_runtime_disable() call afterwards.
>
> Below is another test patch.  Could you check whether this works
> better?
>
>
> Takashi
>
> --- a/sound/pci/hda/hda_codec.c
> +++ b/sound/pci/hda/hda_codec.c
> @@ -2986,13 +2986,11 @@ void snd_hda_codec_shutdown(struct hda_codec *codec)
>   {
>   	struct hda_pcm *cpcm;
>   
> -	if (pm_runtime_suspended(hda_codec_dev(codec)))
> -		return;
> -
>   	list_for_each_entry(cpcm, &codec->pcm_list_head, list)
>   		snd_pcm_suspend_all(cpcm->pcm);
>   
> -	pm_runtime_suspend(hda_codec_dev(codec));
> +	pm_runtime_force_suspend(hda_codec_dev(codec));
> +	pm_runtime_disable(hda_codec_dev(codec));
>   }
>   
>   /*

Hi Takashi,

Thank you very much! Yes, that works fine.  suspend() has been called on 
reboot and no pops.

I still have previous patch in the code, so let me remove it and test it 
again with only snd_hda_codec_shutdown() changes.

Thanks,

Vitaly