Re: [PATCH 2/2] ALSA: hda/cs8409: Prevent pops and clicks during reboot

From: Takashi Iwai
Date: Thu Aug 26 2021 - 06:49:18 EST


On Thu, 26 Aug 2021 08:03:45 +0200,
Takashi Iwai wrote:
>
> On Wed, 25 Aug 2021 20:04:05 +0200,
> Vitaly Rodionov wrote:
> > Actually when codec is suspended and we do reboot from UI, then sometimes we
> > see suspend() calls in kernel log and no pops, but sometimes
> >
> > we still have no suspend() on reboot and we hear pops. But when we do reboot
> > from command line: > sudo reboot  then we always have pops and no suspend()
> > called.
> >
> > Then we have added extra logging and we can see that on reboot codec somehow
> > getting resume() call and we run jack detect on resume that causing pops.
>
> Hm, it's interesting who triggers the runtime resume.
>
> > We were thinking about possible solution for that and we would propose some
> > changes in generic code hda_bind.c:
> >
> > static void hda_codec_driver_shutdown(struct device *dev) { +   if (codec->
> > patch_ops.suspend) +      codec->patch_ops.suspend(codec);   
> > snd_hda_codec_shutdown(dev_to_hda_codec(dev)); +  hda_codec_driver_remove
> > (dev_to_hda_codec(dev)); }
>
> Sorry, it's no-no. The suspend can't be called unconditionally, and
> the driver unbind must not be called in the callback itself.
>
> Does the patch below work instead?

Sorry there was a typo. A bit more revised patch is below.


Takashi

--- a/sound/pci/hda/hda_intel.c
+++ b/sound/pci/hda/hda_intel.c
@@ -1383,14 +1383,17 @@ static void azx_free(struct azx *chip)
hda->freed = 1;
}

-static int azx_dev_disconnect(struct snd_device *device)
+static void __azx_disconnect(struct azx *chip)
{
- struct azx *chip = device->device_data;
struct hdac_bus *bus = azx_bus(chip);

chip->bus.shutdown = 1;
cancel_work_sync(&bus->unsol_work);
+}

+static int azx_dev_disconnect(struct snd_device *device)
+{
+ __azx_disconnect(device->device_data);
return 0;
}

@@ -2356,8 +2359,10 @@ static void azx_shutdown(struct pci_dev *pci)
if (!card)
return;
chip = card->private_data;
- if (chip && chip->running)
+ if (chip && chip->running) {
+ __azx_disconnect(chip);
azx_shutdown_chip(chip);
+ }
}

/* PCI IDs */