ASoC: dapm: add support to pinctrl dapm

Purpose of having pinctrl dapm is to dynamically put the pins in
low power state when they are not actively used by the audio and
saving power.

Without this each driver has to set the pinctrl states, either
during probe or dynamically depending on the callbacks received
from ASoC core.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/soc-dapm.c

@@ -35,6 +35,7 @@
 #include <linux/debugfs.h>
 #include <linux/pm_runtime.h>
 #include <linux/regulator/consumer.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
 #include <sound/core.h>
@@ -72,6 +73,7 @@ snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 static int dapm_up_seq[] = {
 	[snd_soc_dapm_pre] = 0,
 	[snd_soc_dapm_regulator_supply] = 1,
+	[snd_soc_dapm_pinctrl] = 1,
 	[snd_soc_dapm_clock_supply] = 1,
 	[snd_soc_dapm_supply] = 2,
 	[snd_soc_dapm_micbias] = 3,
@@ -121,6 +123,7 @@ static int dapm_down_seq[] = {
 	[snd_soc_dapm_dai_link] = 11,
 	[snd_soc_dapm_supply] = 12,
 	[snd_soc_dapm_clock_supply] = 13,
+	[snd_soc_dapm_pinctrl] = 13,
 	[snd_soc_dapm_regulator_supply] = 13,
 	[snd_soc_dapm_post] = 14,
 };
@@ -1289,6 +1292,31 @@ int dapm_regulator_event(struct snd_soc_dapm_widget *w,
 }
 EXPORT_SYMBOL_GPL(dapm_regulator_event);
 
+/*
+ * Handler for pinctrl widget.
+ */
+int dapm_pinctrl_event(struct snd_soc_dapm_widget *w,
+		       struct snd_kcontrol *kcontrol, int event)
+{
+	struct snd_soc_dapm_pinctrl_priv *priv = w->priv;
+	struct pinctrl *p = w->pinctrl;
+	struct pinctrl_state *s;
+
+	if (!p || !priv)
+		return -EIO;
+
+	if (SND_SOC_DAPM_EVENT_ON(event))
+		s = pinctrl_lookup_state(p, priv->active_state);
+	else
+		s = pinctrl_lookup_state(p, priv->sleep_state);
+
+	if (IS_ERR(s))
+		return PTR_ERR(s);
+
+	return pinctrl_select_state(p, s);
+}
+EXPORT_SYMBOL_GPL(dapm_pinctrl_event);
+
 /*
  * Handler for clock supply widget.
  */
@@ -1902,6 +1930,7 @@ static int dapm_power_widgets(struct snd_soc_card *card, int event)
 				break;
 			case snd_soc_dapm_supply:
 			case snd_soc_dapm_regulator_supply:
+			case snd_soc_dapm_pinctrl:
 			case snd_soc_dapm_clock_supply:
 			case snd_soc_dapm_micbias:
 				if (d->target_bias_level < SND_SOC_BIAS_STANDBY)
@@ -2315,6 +2344,7 @@ static ssize_t dapm_widget_show_component(struct snd_soc_component *cmpnt,
 		case snd_soc_dapm_mixer_named_ctl:
 		case snd_soc_dapm_supply:
 		case snd_soc_dapm_regulator_supply:
+		case snd_soc_dapm_pinctrl:
 		case snd_soc_dapm_clock_supply:
 			if (w->name)
 				count += sprintf(buf + count, "%s: %s\n",
@@ -3464,6 +3494,17 @@ snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 					 w->name, ret);
 		}
 		break;
+	case snd_soc_dapm_pinctrl:
+		w->pinctrl = devm_pinctrl_get(dapm->dev);
+		if (IS_ERR_OR_NULL(w->pinctrl)) {
+			ret = PTR_ERR(w->pinctrl);
+			if (ret == -EPROBE_DEFER)
+				return ERR_PTR(ret);
+			dev_err(dapm->dev, "ASoC: Failed to request %s: %d\n",
+				w->name, ret);
+			return NULL;
+		}
+		break;
 	case snd_soc_dapm_clock_supply:
 #ifdef CONFIG_CLKDEV_LOOKUP
 		w->clk = devm_clk_get(dapm->dev, w->name);
@@ -3543,6 +3584,7 @@ snd_soc_dapm_new_control_unlocked(struct snd_soc_dapm_context *dapm,
 		break;
 	case snd_soc_dapm_supply:
 	case snd_soc_dapm_regulator_supply:
+	case snd_soc_dapm_pinctrl:
 	case snd_soc_dapm_clock_supply:
 	case snd_soc_dapm_kcontrol:
 		w->is_supply = 1;