On Wed, 03 Jun 2020 14:39:24 +0200, Macpaul Lin wrote:

On Wed, 2020-06-03 at 10:45 +0200, Takashi Iwai wrote:

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On Wed, 03 Jun 2020 08:54:51 +0200, Takashi Iwai wrote:

...

On Wed, 03 Jun 2020 08:28:09 +0200, Takashi Iwai wrote:

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And, the most suspicious case is the last one, chip->num_suspended-intf. It means that the device has multiple USB interfaces and they went to suspend, while the resume isn't performed for the all suspended interfaces in return.

If this is the cause, a patch like below might help. It gets/puts the all assigned interfaced instead of only the primary one.

... and considering of the problem again, rather the patch below might be the right answer. Now the driver tries to remember at which state it entered into the system-suspend. Upon resume, in return, when the state reaches back to that point, set the card state to D0.

The previous patch can be applied on the top, too, and it might be worth to apply both.

Let me know if any of those actually helps.

Takashi

Thanks for your response so quickly. I've just test this patch since it looks like enough for the issue.

Good to hear!

This patch worked since the flag system_suspend will be set at the same time when power state has been changed. I have 2 interface with the head set. But actually the problem happened when primary one is suspended.

Currently the autosuspend is set only to the primary interface; IOW, the other interfaces will never get autosuspend, and the another suspend-all-intf patch should improve that situation. But it won't fix your actual bug, obviously :)

So I didn't test the earlier patch "suspend all interface instead of only the primary one."

Could you try it one on top of the last patch? At least I'd like to see whether it causes any regression.

Will you resend this patch officially later? I think this solution is required to send to stable, too. It's better to have it for other stable kernel versions include android's.

Yes, that's a general bug and worth to be merged quickly. I'm going to submit a proper patch soon later.

thanks,

Takashi

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diff --git a/sound/usb/card.c b/sound/usb/card.c --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -843,9 +843,6 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message) if (chip == (void *)-1L) return 0;

• chip->autosuspended = !!PMSG_IS_AUTO(message);
• if (!chip->autosuspended)

• snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
  

  if (!chip->num_suspended_intf++) { list_for_each_entry(as, &chip->pcm_list, list) { snd_usb_pcm_suspend(as);

@@ -858,6 +855,11 @@ static int usb_audio_suspend(struct usb_interface *intf, pm_message_t message) snd_usb_mixer_suspend(mixer); }

• if (!PMSG_IS_AUTO(message) && !chip->system_suspend) {

• snd_power_change_state(chip->card, SNDRV_CTL_POWER_D3hot);
  

• chip->system_suspend = chip->num_suspended_intf;
  

• }
• return 0;

} @@ -871,10 +873,10 @@ static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume) if (chip == (void *)-1L) return 0;

• if (--chip->num_suspended_intf)

• return 0;
  

atomic_inc(&chip->active); /* avoid autopm */

• if (chip->num_suspended_intf > 1)

• goto out;
  

list_for_each_entry(as, &chip->pcm_list, list) { err = snd_usb_pcm_resume(as); @@ -896,9 +898,12 @@ static int __usb_audio_resume(struct usb_interface *intf, bool reset_resume) snd_usbmidi_resume(p); }

• if (!chip->autosuspended)

• out:
• if (chip->num_suspended_intf == chip->system_suspend) { snd_power_change_state(chip->card, SNDRV_CTL_POWER_D0);

• chip->autosuspended = 0;

• chip->system_suspend = 0;
  

• }
• chip->num_suspended_intf--;

err_out: atomic_dec(&chip->active); /* allow autopm after this point */ diff --git a/sound/usb/usbaudio.h b/sound/usb/usbaudio.h index 1c892c7f14d7..e0ebfb25fbd5 100644 --- a/sound/usb/usbaudio.h +++ b/sound/usb/usbaudio.h @@ -26,7 +26,7 @@ struct snd_usb_audio { struct usb_interface *pm_intf; u32 usb_id; struct mutex mutex;

• unsigned int autosuspended:1;

• unsigned int system_suspend; atomic_t active; atomic_t shutdown; atomic_t usage_count;

---

Thank you very much!

Best regards, Macpaul Lin