Re: [PATCH 2/3] ALSA: hda - WAKEEN feature enabling for runtime pm

[David Henningsson <david.henningsson@canonical.com>]

On 07/22/2013 09:19 AM, Wang Xingchao wrote:
> With runtime power save feature enabled, Headphone hotplug
> event will not be detected while controller/codec in D3. HDA has
> feature WAKEEN to let codec wake up system if controller is in D3 or
> system in S3.(HDA Spec 4.5.9.2/3). Codec can send out INT or wake up
> controller depending on whether CIE or GIE enabled.(Figure 4, Interupt
> structure).

Oh, so you actually got it working? Nice! :-)

> The controller must be in RESET mode after enter runtime-suspend, otherwise
> it will not be waken up even if codec send out wake-up event. And STATESTS
> will be cleared after controller brought out of RESET mode.

There seems to be nothing in this patch that sets the controller in 
RESET mode, is this something done in a later patch, or is that code 
already present today, or...?

> This patch only enable WAKEEN for runtime-suspend(Controller D3) mode,
> not for system S3 mode. with tool "evtest", Headphone hotplug events
> could be cought and reported successfully.

>
> Signed-off-by: Wang Xingchao <xingchao.wang@linux.intel.com>
> ---
>   sound/pci/hda/hda_intel.c | 25 +++++++++++++++++++++++++
>   1 file changed, 25 insertions(+)
>
> diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c
> index 8860dd5..a7ac7fd 100644
> --- a/sound/pci/hda/hda_intel.c
> +++ b/sound/pci/hda/hda_intel.c
> @@ -2970,6 +2970,11 @@ static int azx_runtime_suspend(struct device *dev)
>   {
>   	struct snd_card *card = dev_get_drvdata(dev);
>   	struct azx *chip = card->private_data;
> +	int status;
> +
> +	/* enable controller wake up event */
> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) |
> +		  STATESTS_INT_MASK);
>
>   	azx_stop_chip(chip);
>   	azx_enter_link_reset(chip);
> @@ -2983,11 +2988,31 @@ static int azx_runtime_resume(struct device *dev)
>   {
>   	struct snd_card *card = dev_get_drvdata(dev);
>   	struct azx *chip = card->private_data;
> +	struct hda_bus *bus;
> +	struct hda_codec *codec;
> +	int status;
>
>   	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
>   		hda_display_power(true);
> +
> +	/* Read STATESTS before controller reset */
> +	status = azx_readw(chip, STATESTS);
> +
>   	azx_init_pci(chip);
>   	azx_init_chip(chip, 1);
> +
> +	bus = chip->bus;
> +	if (status && bus) {
> +		list_for_each_entry(codec, &bus->codec_list, list)
> +			if (status & (1 << codec->addr))
> +				queue_delayed_work(codec->bus->workq,
> +						   &codec->jackpoll_work, codec->jackpoll_interval);

Is there a reason you want to move the jack detection to a delayed work, 
i e, why can't we just call:

  	snd_hda_jack_set_dirty_all(codec);
  	snd_hda_jack_poll_all(codec);

...from here?

> +	}
> +
> +	/* disable controller Wake Up event*/
> +	azx_writew(chip, WAKEEN, azx_readw(chip, WAKEEN) &
> +			~STATESTS_INT_MASK);
> +
>   	return 0;
>   }
>
>



-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic