Partially reverts commit 128f825aeab7 ("ASoC: max98357a: move control of SD_MODE to DAPM").

In order to have mute control of max98357 from machine drivers, commit 128f825aeab7 ("ASoC: max98357a: move control of SD_MODE to DAPM") moves the control of SD_MODE from DAI ops to DAPM events. However, pop noise has been observed on rk3399-gru-kevin boards due to this commit.

The commit 128f825aeab7 caused sequence of DAI clocks and SD_MODE changed on rk3399-gru-kevin boards.

With the commit 128f825aeab7: - SD_MODE will be set to 1 before DAI clocks start. - SD_MODE will be set to 0 after DAI clocks stop. As a result, pop noise.

Moves the control of SD_MODE back to DAI ops. In the meantime, uses an additional flag in DAPM event to provide chance of mute control for machine drivers.

Signed-off-by: Tzung-Bi Shih tzungbi@google.com ---

This patch addresses the reported issue in the thread https://lkml.org/lkml/2020/7/16/427

sound/soc/codecs/max98357a.c | 50 ++++++++++++++++++++++++++++-------- 1 file changed, 40 insertions(+), 10 deletions(-)

diff --git a/sound/soc/codecs/max98357a.c b/sound/soc/codecs/max98357a.c index 4f431133d0bb..918812763884 100644 --- a/sound/soc/codecs/max98357a.c +++ b/sound/soc/codecs/max98357a.c @@ -23,36 +23,61 @@ struct max98357a_priv { struct gpio_desc *sdmode; unsigned int sdmode_delay; + int sdmode_switch; };

-static int max98357a_sdmode_event(struct snd_soc_dapm_widget *w, - struct snd_kcontrol *kcontrol, int event) +static int max98357a_daiops_trigger(struct snd_pcm_substream *substream, + int cmd, struct snd_soc_dai *dai) { - struct snd_soc_component *component = - snd_soc_dapm_to_component(w->dapm); + struct snd_soc_component *component = dai->component; struct max98357a_priv *max98357a = snd_soc_component_get_drvdata(component);

if (!max98357a->sdmode) return 0;

- if (event & SND_SOC_DAPM_POST_PMU) { - msleep(max98357a->sdmode_delay); - gpiod_set_value(max98357a->sdmode, 1); - dev_dbg(component->dev, "set sdmode to 1"); - } else if (event & SND_SOC_DAPM_PRE_PMD) { + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: + mdelay(max98357a->sdmode_delay); + if (max98357a->sdmode_switch) { + gpiod_set_value(max98357a->sdmode, 1); + dev_dbg(component->dev, "set sdmode to 1"); + } + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: gpiod_set_value(max98357a->sdmode, 0); dev_dbg(component->dev, "set sdmode to 0"); + break; }

return 0; }

+static int max98357a_sdmode_event(struct snd_soc_dapm_widget *w, + struct snd_kcontrol *kcontrol, int event) +{ + struct snd_soc_component *component = + snd_soc_dapm_to_component(w->dapm); + struct max98357a_priv *max98357a = + snd_soc_component_get_drvdata(component); + + if (event & SND_SOC_DAPM_POST_PMU) + max98357a->sdmode_switch = 1; + else if (event & SND_SOC_DAPM_POST_PMD) + max98357a->sdmode_switch = 0; + + return 0; +} + static const struct snd_soc_dapm_widget max98357a_dapm_widgets[] = { SND_SOC_DAPM_OUTPUT("Speaker"), SND_SOC_DAPM_OUT_DRV_E("SD_MODE", SND_SOC_NOPM, 0, 0, NULL, 0, max98357a_sdmode_event, - SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_PRE_PMD), + SND_SOC_DAPM_POST_PMU | SND_SOC_DAPM_POST_PMD), };

static const struct snd_soc_dapm_route max98357a_dapm_routes[] = { @@ -71,6 +96,10 @@ static const struct snd_soc_component_driver max98357a_component_driver = { .non_legacy_dai_naming = 1, };

+static const struct snd_soc_dai_ops max98357a_dai_ops = { + .trigger = max98357a_daiops_trigger, +}; + static struct snd_soc_dai_driver max98357a_dai_driver = { .name = "HiFi", .playback = { @@ -90,6 +119,7 @@ static struct snd_soc_dai_driver max98357a_dai_driver = { .channels_min = 1, .channels_max = 2, }, + .ops = &max98357a_dai_ops, };

static int max98357a_platform_probe(struct platform_device *pdev)