-----Original Message----- From: Takashi Iwai [mailto:tiwai@suse.de] Sent: Thursday, March 28, 2019 3:15 PM To: Yang, Libin libin.yang@intel.com Cc: 'alsa-devel@alsa-project.org' alsa-devel@alsa-project.org; 'broonie@kernel.org' broonie@kernel.org Subject: Re: [alsa-devel] [PATCH V2] ASoC: fix hdmi codec driver contest in S3
On Thu, 28 Mar 2019 08:10:34 +0100, Yang, Libin wrote:
Hi Takashi,
> >In the case of legacy HD-audio, we "fixed" the problem by > >avoiding the trigger of async work at resume, but let it be > >triggered from runtime resume. In ASoC case, however, it's no
option.
> > > >Maybe a possible solution in the sound driver side would be to > >move from system suspend/resume to ASoC component
suspend/resume.
> >The runtime suspend/resume can be kept as is, and call > >pm_runtime_force_suspend and resume from the component suspend/resume > >callbacks. Since the component callbacks are certainly > >processed before DAPM events, this should assure the order. > > I tried to move display power setting from runtime > suspend/resume to component suspend/resume. I found there may
be another issue:
> playback will NOT call component suspend/resume. > This means we will never have chance to set the display power > if we don't do the S3.
The runtime suspend/resume are fine and need to be kept, I suppose. The only problem is the system suspend/resume callbacks that call pm_runtime_force_*(). Just moving these two to component would
work?
Let's see the flow of the suspend:
- Component suspend is called. It will call
snd_hdac_display_power() to turn off the display power.
No, what I meant was to make the component suspend calling pm_runtime_force_suspend() instead of the system suspend. Ditto for the component resume calling pm_runtime_force_resume().
It seems this component suspend/resume method works well. I will do more test and send out the patch later.
I did some stress test. And I found if I remove the debug message, the issue can still be reproduced with component suspend/resume added. If I add the debug message, it will be much better. I'm not sure whether my patch is wrong or not. I've set the bus_control = 1 in the dai driver.
I guess you forgot to remove the suspend/resume call from the codec device PM? Otherwise the codec device resume is still executed concurrently.
... Yes, I forgot it. Thanks for reminder. By the way, do you think it is better to use pm_runtime_force_resume() or pm_runtime_get_sync()?
Regards, Libin
Takashi
diff --git a/sound/soc/codecs/hdac_hdmi.c b/sound/soc/codecs/hdac_hdmi.c index 5eeb0fe..505efd9 100644 --- a/sound/soc/codecs/hdac_hdmi.c +++ b/sound/soc/codecs/hdac_hdmi.c @@ -1900,9 +1900,31 @@ static int hdmi_codec_resume(struct device *dev) #define hdmi_codec_resume NULL #endif
+static int hdmi_component_suspend(struct snd_soc_component +*component) {
struct hdac_hdmi_priv *hdmi =snd_soc_component_get_drvdata(component);
struct hdac_device *hdev = hdmi->hdev;pm_runtime_force_suspend(&hdev->dev);return 0;+}
+static int hdmi_component_resume(struct snd_soc_component
*component)
+{
struct hdac_hdmi_priv *hdmi =snd_soc_component_get_drvdata(component);
struct hdac_device *hdev = hdmi->hdev;pm_runtime_force_resume(&hdev->dev);return 0;+}
static const struct snd_soc_component_driver hdmi_hda_codec = { .probe = hdmi_codec_probe, .remove = hdmi_codec_remove,
.suspend = hdmi_component_suspend,.resume = hdmi_component_resume, .use_pmdown_time = 1, .endianness = 1, .non_legacy_dai_naming = 1,Regards, Libin