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Message-ID: <8a91822c-d68a-a2d8-6865-3985f2f85c0b@linaro.org>
Date:   Thu, 21 Apr 2022 10:31:23 +0100
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Subject: Re: [PATCH v4] ASoC: codecs: wsa881x: add runtime pm support
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To:     Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        broonie@kernel.org
Cc:     alsa-devel@alsa-project.org, lgirdwood@gmail.com,
        linux-kernel@vger.kernel.org, tiwai@suse.com,
        quic_srivasam@quicinc.com
References: <20220228144235.24208-1-srinivas.kandagatla@linaro.org>
 <b1b0a8b9-5fc2-bfe1-dfde-692a0a7ac34a@linux.intel.com>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
In-Reply-To: <b1b0a8b9-5fc2-bfe1-dfde-692a0a7ac34a@linux.intel.com>
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On 20/04/2022 18:59, Pierre-Louis Bossart wrote:
> Hi Srini,
> 
>> +static int __maybe_unused wsa881x_runtime_resume(struct device *dev)
>> +{
>> +	struct sdw_slave *slave = dev_to_sdw_dev(dev);
>> +	struct regmap *regmap = dev_get_regmap(dev, NULL);
>> +	struct wsa881x_priv *wsa881x = dev_get_drvdata(dev);
>> +
>> +	gpiod_direction_output(wsa881x->sd_n, 1);
>> +
>> +	wait_for_completion_timeout(&slave->initialization_complete,
>> +				    msecs_to_jiffies(WSA881X_PROBE_TIMEOUT));
> 
> while I was revisiting pm_runtime support, I also saw that this codec driver is the only one that doesn't check for errors
> 
> max98373-sdw.c: time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt1308-sdw.c:   time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt1316-sdw.c:   time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt5682-sdw.c:   time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt5682.c:                       &slave->initialization_complete,
> 
> rt700-sdw.c:    time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt711-sdca-sdw.c:       time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt711-sdw.c:    time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> rt715-sdw.c:    time = wait_for_completion_timeout(&slave->initialization_complete,
> 
> wsa881x.c:      wait_for_completion_timeout(&slave->initialization_complete,
> 
> 
> If the attachment fails for some reason, you probably want to avoid starting regmap syncs that will fail by construction, no?

Thanks Pierre for auditing the calls.

Yes syncs would fail on reg writes if initialization timeout.
Do you already have fix patch to this or do you want me to send one?

Am also trying to understand what is the expected behavior in the resume 
failure cases, should pm attempt to resume the codec after some time, if 
so returning -ETIMEOUT is the right error code?


--srini
> 
>> +
>> +	regcache_cache_only(regmap, false);
>> +	regcache_sync(regmap);
>> +
>> +	return 0;
>> +}