ASoC: max98357a: move control of SD_MODE back to DAI ops

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>
Tested-By: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Link: https://lore.kernel.org/r/20200721114232.2812254-1-tzungbi@google.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/max98357a.c b/sound/soc/codecs/max98357a.c
index a8bd793..151f05a 100644 (file)
--- 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)