ASoC: Specify target bias state directly as a bias state

Rather than a simple flag to say if we want the DAPM context to be at full
power specify the target bias state. This should have no current effect
but is a bit more direct and so makes it easier to change our decisions
about the which bias state to go into in future.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>

include/sound/soc-dapm.h

@@ -510,7 +510,7 @@ struct snd_soc_dapm_context {
 	struct snd_soc_card *card; /* parent card */
 
 	/* used during DAPM updates */
-	int dev_power;
+	enum snd_soc_bias_level target_bias_level;
 	struct list_head list;
 
 #ifdef CONFIG_DEBUG_FS

include/sound/soc.h

@@ -214,10 +214,10 @@
  * @OFF:     Power Off. No restrictions on transition times.
  */
 enum snd_soc_bias_level {
-	SND_SOC_BIAS_OFF,
-	SND_SOC_BIAS_STANDBY,
-	SND_SOC_BIAS_PREPARE,
-	SND_SOC_BIAS_ON,
+	SND_SOC_BIAS_OFF = 0,
+	SND_SOC_BIAS_STANDBY = 1,
+	SND_SOC_BIAS_PREPARE = 2,
+	SND_SOC_BIAS_ON = 3,
 };
 
 struct snd_jack;

sound/soc/soc-dapm.c

@@ -1042,16 +1042,17 @@ static void dapm_pre_sequence_async(void *data, async_cookie_t cookie)
 	struct snd_soc_dapm_context *d = data;
 	int ret;
 
-	if (d->dev_power && d->bias_level == SND_SOC_BIAS_OFF) {
+	/* If we're off and we're not supposed to be go into STANDBY */
+	if (d->bias_level == SND_SOC_BIAS_OFF &&
+	    d->target_bias_level != SND_SOC_BIAS_OFF) {
 		ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_STANDBY);
 		if (ret != 0)
 			dev_err(d->dev,
 				"Failed to turn on bias: %d\n", ret);
 	}
 
-	/* If we're changing to all on or all off then prepare */
-	if ((d->dev_power && d->bias_level == SND_SOC_BIAS_STANDBY) ||
-	    (!d->dev_power && d->bias_level == SND_SOC_BIAS_ON)) {
+	/* Prepare for a STADDBY->ON or ON->STANDBY transition */
+	if (d->bias_level != d->target_bias_level) {
 		ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_PREPARE);
 		if (ret != 0)
 			dev_err(d->dev,
@@ -1068,7 +1069,9 @@ static void dapm_post_sequence_async(void *data, async_cookie_t cookie)
 	int ret;
 
 	/* If we just powered the last thing off drop to standby bias */
-	if (d->bias_level == SND_SOC_BIAS_PREPARE && !d->dev_power) {
+	if (d->bias_level == SND_SOC_BIAS_PREPARE &&
+	    (d->target_bias_level == SND_SOC_BIAS_STANDBY ||
+	     d->target_bias_level == SND_SOC_BIAS_OFF)) {
 		ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_STANDBY);
 		if (ret != 0)
 			dev_err(d->dev, "Failed to apply standby bias: %d\n",
@@ -1076,14 +1079,16 @@ static void dapm_post_sequence_async(void *data, async_cookie_t cookie)
 	}
 
 	/* If we're in standby and can support bias off then do that */
-	if (d->bias_level == SND_SOC_BIAS_STANDBY && d->idle_bias_off) {
+	if (d->bias_level == SND_SOC_BIAS_STANDBY &&
+	    d->target_bias_level == SND_SOC_BIAS_OFF) {
 		ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_OFF);
 		if (ret != 0)
 			dev_err(d->dev, "Failed to turn off bias: %d\n", ret);
 	}
 
 	/* If we just powered up then move to active bias */
-	if (d->bias_level == SND_SOC_BIAS_PREPARE && d->dev_power) {
+	if (d->bias_level == SND_SOC_BIAS_PREPARE &&
+	    d->target_bias_level == SND_SOC_BIAS_ON) {
 		ret = snd_soc_dapm_set_bias_level(d, SND_SOC_BIAS_ON);
 		if (ret != 0)
 			dev_err(d->dev, "Failed to apply active bias: %d\n",
@@ -1108,13 +1113,19 @@ static int dapm_power_widgets(struct snd_soc_dapm_context *dapm, int event)
 	LIST_HEAD(up_list);
 	LIST_HEAD(down_list);
 	LIST_HEAD(async_domain);
+	enum snd_soc_bias_level bias;
 	int power;
 
 	trace_snd_soc_dapm_start(card);
 
-	list_for_each_entry(d, &card->dapm_list, list)
-		if (d->n_widgets || d->codec == NULL)
-			d->dev_power = 0;
+	list_for_each_entry(d, &card->dapm_list, list) {
+		if (d->n_widgets || d->codec == NULL) {
+			if (d->idle_bias_off)
+				d->target_bias_level = SND_SOC_BIAS_OFF;
+			else
+				d->target_bias_level = SND_SOC_BIAS_STANDBY;
+		}
+	}
 
 	/* Check which widgets we need to power and store them in
 	 * lists indicating if they should be powered up or down.
@@ -1137,7 +1148,7 @@ static int dapm_power_widgets(struct snd_soc_dapm_context *dapm, int event)
 			else
 				power = 1;
 			if (power)
-				w->dapm->dev_power = 1;
+				w->dapm->target_bias_level = SND_SOC_BIAS_ON;
 
 			if (w->power == power)
 				continue;
@@ -1161,24 +1172,19 @@ static int dapm_power_widgets(struct snd_soc_dapm_context *dapm, int event)
 		switch (event) {
 		case SND_SOC_DAPM_STREAM_START:
 		case SND_SOC_DAPM_STREAM_RESUME:
-			dapm->dev_power = 1;
+			dapm->target_bias_level = SND_SOC_BIAS_ON;
 			break;
 		case SND_SOC_DAPM_STREAM_STOP:
-			dapm->dev_power = !!dapm->codec->active;
+			if (dapm->codec->active)
+				dapm->target_bias_level = SND_SOC_BIAS_ON;
+			else
+				dapm->target_bias_level = SND_SOC_BIAS_STANDBY;
 			break;
 		case SND_SOC_DAPM_STREAM_SUSPEND:
-			dapm->dev_power = 0;
+			dapm->target_bias_level = SND_SOC_BIAS_STANDBY;
 			break;
 		case SND_SOC_DAPM_STREAM_NOP:
-			switch (dapm->bias_level) {
-				case SND_SOC_BIAS_STANDBY:
-				case SND_SOC_BIAS_OFF:
-					dapm->dev_power = 0;
-					break;
-				default:
-					dapm->dev_power = 1;
-					break;
-			}
+			dapm->target_bias_level = dapm->bias_level;
 			break;
 		default:
 			break;
@@ -1186,12 +1192,12 @@ static int dapm_power_widgets(struct snd_soc_dapm_context *dapm, int event)
 	}
 
 	/* Force all contexts in the card to the same bias state */
-	power = 0;
+	bias = SND_SOC_BIAS_OFF;
 	list_for_each_entry(d, &card->dapm_list, list)
-		if (d->dev_power)
-			power = 1;
+		if (d->target_bias_level > bias)
+			bias = d->target_bias_level;
 	list_for_each_entry(d, &card->dapm_list, list)
-		d->dev_power = power;
+		d->target_bias_level = bias;
 
 
 	/* Run all the bias changes in parallel */