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Date:   Wed, 19 Jul 2023 17:31:28 +0200
Message-ID: <87edl3lxyn.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Cezary Rojewski <cezary.rojewski@intel.com>
Cc:     Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        <alsa-devel@alsa-project.org>,
        <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>
Subject: Re: [PATCH 3/7] ASoC: Intel: avs: Move snd_hdac_i915_init to before probe_work.
In-Reply-To: <18fb40b9-f5b4-60d8-79df-e0719cf48231@intel.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>
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On Wed, 19 Jul 2023 17:26:24 +0200,
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.

Yeah, we need some workaround to let user to skip the i915 binding, as
discussed in the thread.  I guess an option for hdac_i915 (that will
be in snd-hda-core module) should suffice.


thanks,

Takashi