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Message-ID: <a913df90-174c-7132-bbfa-bf30f0664d9c@linux.intel.com>
Date:   Wed, 19 Jul 2023 17:54:34 +0200
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Subject: Re: [PATCH 3/7] ASoC: Intel: avs: Move snd_hdac_i915_init to before
 probe_work.
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To:     Cezary Rojewski <cezary.rojewski@intel.com>,
        alsa-devel@alsa-project.org
Cc:     sound-open-firmware@alsa-project.org, linux-kernel@vger.kernel.org,
        Jaroslav Kysela <perex@perex.cz>,
        Takashi Iwai <tiwai@suse.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        Liam Girdwood <liam.r.girdwood@linux.intel.com>,
        Peter Ujfalusi <peter.ujfalusi@linux.intel.com>,
        Bard Liao <yung-chuan.liao@linux.intel.com>,
        Ranjani Sridharan <ranjani.sridharan@linux.intel.com>,
        Kai Vehmanen <kai.vehmanen@linux.intel.com>,
        Mark Brown <broonie@kernel.org>,
        Daniel Baluta <daniel.baluta@nxp.com>
References: <20230718084522.116952-1-maarten.lankhorst@linux.intel.com>
 <20230718084522.116952-4-maarten.lankhorst@linux.intel.com>
 <18fb40b9-f5b4-60d8-79df-e0719cf48231@intel.com>
From:   Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
In-Reply-To: <18fb40b9-f5b4-60d8-79df-e0719cf48231@intel.com>
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Precedence: bulk

Hey,

On 2023-07-19 17:26, Cezary Rojewski wrote:
> On 2023-07-18 10:45 AM, Maarten Lankhorst wrote:
>> Now that we can use -EPROBE_DEFER, it's no longer required to spin off
>> the snd_hdac_i915_init into a workqueue. It's likely the whole workqueue
>> can be destroyed, but I don't have the means to test this.
>>
>> Removing the workqueue would simplify init even further, but is left
>> as exercise for the reviewer.
>>
>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
>> ---
>>   sound/soc/intel/avs/core.c | 13 +++++++++----
>>   1 file changed, 9 insertions(+), 4 deletions(-)
>>
>> diff --git a/sound/soc/intel/avs/core.c b/sound/soc/intel/avs/core.c
>> index 3311a6f142001..d3a7f42387e9b 100644
>> --- a/sound/soc/intel/avs/core.c
>> +++ b/sound/soc/intel/avs/core.c
>> @@ -191,10 +191,6 @@ static void avs_hda_probe_work(struct work_struct 
>> *work)
>>       pm_runtime_set_active(bus->dev); /* clear runtime_error flag */
>> -    ret = snd_hdac_i915_init(bus, true);
>> -    if (ret < 0)
>> -        dev_info(bus->dev, "i915 init unsuccessful: %d\n", ret);
>> -
>>       snd_hdac_display_power(bus, HDA_CODEC_IDX_CONTROLLER, true);
>>       avs_hdac_bus_init_chip(bus, true);
>>       avs_hdac_bus_probe_codecs(bus);
>> @@ -465,10 +461,19 @@ static int avs_pci_probe(struct pci_dev *pci, 
>> const struct pci_device_id *id)
>>       pci_set_drvdata(pci, bus);
>>       device_disable_async_suspend(dev);
>> +    ret = snd_hdac_i915_init(bus, false);
>> +    if (ret == -EPROBE_DEFER)
>> +        goto err_unmaster;
>> +    else if (ret < 0)
>> +        dev_info(bus->dev, "i915 init unsuccessful: %d\n", ret);
>> +
> 
> While our tests are currently passing I have my doubts about 
> EPROBE_DEFER. We do want to have audio functionality there even if some 
> problems with HDMI arise along the way - some audio is better than no 
> audio. Here, i915 may ruin the day for a platform equipped with 
> hda/hdmi/i2c/dmic chips simultaneously.
> 
> Also, why call snd_hdac_i915_init() _after_ setting drvdata?

I wanted to make the most cautious change. The previous flow called the 
function immediately from probe_work, so I moved it to right before the 
scheduling of probe_work

>>       schedule_work(&adev->probe_work);
>>       return 0;
>> +err_unmaster:
>> +    pci_clear_master(pci);
>> +    pci_set_drvdata(pci, NULL);
> 
> Not a fan. It's hard to grasp entire error-step within name of a single 
> label. Thus I'd suggest "err_<cause>" naming pattern instead. Even here, 
> under "unmaster" you hid clearing master and drvdata both. Let's do 
> "err_i915_init" instead.
> 
Ok, will rename.

~Maarten