Re: [PATCH 1/3] ASoC: mediatek: mt8188-mt6359: support dynamic pinctrl

[AngeloGioacchino Del Regno]

Il 25/07/23 05:53, Trevor Wu ha scritto:
> To avoid power leakage, it is recommended to replace the default pinctrl
> state with dynamic pinctrl since certain audio pinmux functions can
> remain in a HIGH state even when audio is disabled. Linking pinctrl with
> DAPM using SND_SOC_DAPM_PINCTRL will ensure that audio pins remain in
> GPIO mode by default and only switch to an audio function when necessary.
>
> Signed-off-by: Trevor Wu <trevor.wu@xxxxxxxxxxxx>
> ---
>   sound/soc/mediatek/mt8188/mt8188-mt6359.c | 21 +++++++++++++++++++++
>   1 file changed, 21 insertions(+)
>
> diff --git a/sound/soc/mediatek/mt8188/mt8188-mt6359.c b/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> index 7c9e08e6a4f5..667d79f33bf2 100644
> --- a/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> +++ b/sound/soc/mediatek/mt8188/mt8188-mt6359.c
> @@ -246,6 +246,11 @@ static const struct snd_soc_dapm_widget mt8188_mt6359_widgets[] = {
>   	SND_SOC_DAPM_MIC("Headset Mic", NULL),
>   	SND_SOC_DAPM_SINK("HDMI"),
>   	SND_SOC_DAPM_SINK("DP"),
> +
> +	/* dynamic pinctrl */
> +	SND_SOC_DAPM_PINCTRL("ETDM_SPK_PIN", "aud_etdm_spk_on", "aud_etdm_spk_off"),
> +	SND_SOC_DAPM_PINCTRL("ETDM_HP_PIN", "aud_etdm_hp_on", "aud_etdm_hp_off"),
> +	SND_SOC_DAPM_PINCTRL("MTKAIF_PIN", "aud_mtkaif_on", "aud_mtkaif_off"),
>   };
>   
>   static const struct snd_kcontrol_new mt8188_mt6359_controls[] = {
> @@ -267,6 +272,7 @@ static int mt8188_mt6359_mtkaif_calibration(struct snd_soc_pcm_runtime *rtd)
>   		snd_soc_rtdcom_lookup(rtd, AFE_PCM_NAME);
>   	struct snd_soc_component *cmpnt_codec =
>   		asoc_rtd_to_codec(rtd, 0)->component;
> +	struct snd_soc_dapm_widget *pin_w = NULL, *w;
>   	struct mtk_base_afe *afe;
>   	struct mt8188_afe_private *afe_priv;
>   	struct mtkaif_param *param;
> @@ -306,6 +312,18 @@ static int mt8188_mt6359_mtkaif_calibration(struct snd_soc_pcm_runtime *rtd)
>   		return 0;
>   	}
>   
> +	for_each_card_widgets(rtd->card, w) {
> +		if (!strcmp(w->name, "MTKAIF_PIN")) {

if (strncmp(w->name, "MTKAIF_PIN", strlen(w->name) == 0) {
	pin_w = w;
	break;
}

That's safer.

> +			pin_w = w;
> +			break;
> +		}
> +	}
> +
> +	if (!pin_w)

Just a nitpick: you're checking for `if (pin_w)` later in this function, so
to increase readability please do the same here.

if (pin_w)
	dapm_pinctrl_event(...)
else
	dev_dbg(...)

Regards,
Angelo