[alsa-devel] [PATCH v2 12/15] ASoC: soc-core: add missing return value check for soc_link_init()

[Pierre-Louis Bossart]

On 11/27/19 12:48 AM, Kuninori Morimoto wrote:
> 
> Hi Pierre-Louis
> 
>>> diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
>>> index 79a4753..bdae48e 100644
>>> --- a/sound/soc/soc-core.c
>>> +++ b/sound/soc/soc-core.c
>>> @@ -1983,8 +1983,11 @@ static int snd_soc_bind_card(struct snd_soc_card *card)
>>>    		goto probe_end;
>>>    	}
>>>    -	for_each_card_rtds(card, rtd)
>>> -		soc_link_init(card, rtd);
>>> +	for_each_card_rtds(card, rtd) {
>>> +		ret = soc_link_init(card, rtd);
>>> +		if (ret < 0)
>>> +			goto probe_end;
>>> +	}
>>
>> Morimoto-san, this patch proves very useful to avoid a kernel oops
>> when a dailink init fails, but I still see a warning when cleaning-up.
>>
>> I was experimenting with a topology file that wasn't complete and came
>> across the warning below, would you have any ideas/recommendations on
>> what might be missing? I am running out of time this week so thought I
>> would ask, in case this rings a bell.
>>
>> Thanks!
>>
>> [   21.098662] bytcr_rt5640 bytcr_rt5640: ASoC: no source widget found
>> for modem_out
>> [   21.098677] bytcr_rt5640 bytcr_rt5640: ASoC: Failed to add route
>> modem_out -> direct -> ssp0 Tx
>> [   21.098694] bytcr_rt5640 bytcr_rt5640: ASoC: no sink widget found
>> for modem_in
>> [   21.098703] bytcr_rt5640 bytcr_rt5640: ASoC: Failed to add route
>> ssp0 Rx -> direct -> modem_in
>> [   21.098732] bytcr_rt5640 bytcr_rt5640: ASoC: failed to init
>> SSP2-Codec: -19
> 
> Do you mean, it could save you from Oops, but you still have warning ?

Correct.

> 
> It seems soc-dapm::snd_soc_dapm_add_routes() failed.
> Your kernel is missing widget route/path ?
> Or, sound card driver has some issue ?
> 
> I have been faced this error many times.
> I don't remember detail, but, if my memory was correct,
> it was always card driver setup timing, or missing something, in my case.

In this case it's a bad topology that does not contain widgets that the 
machine driver uses. Still that should be handled gracefully without 
warnings.