ASoC: dapm: Add a update parameter to snd_soc_dapm_{mux,mixer}_update_power

In order to avoid race conditions the assignment of dapm->update should happen
while card->dapm_mutex is being held. To allow CODEC drivers to run a register
update when using snd_soc_dapm_mux_update_power() or
snd_soc_dapm_mixer_update_power() add a update parameter to these two functions.
The update parameter will be assigned to dapm->update while card->dapm_mutex is
locked.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 6f8a01b..7587611 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -1982,13 +1982,16 @@
 }
 
 int snd_soc_dapm_mux_update_power(struct snd_soc_dapm_context *dapm,
-	struct snd_kcontrol *kcontrol, int mux, struct soc_enum *e)
+	struct snd_kcontrol *kcontrol, int mux, struct soc_enum *e,
+	struct snd_soc_dapm_update *update)
 {
 	struct snd_soc_card *card = dapm->card;
 	int ret;
 
 	mutex_lock_nested(&card->dapm_mutex, SND_SOC_DAPM_CLASS_RUNTIME);
+	dapm->update = update;
 	ret = soc_dapm_mux_update_power(dapm, kcontrol, mux, e);
+	dapm->update = NULL;
 	mutex_unlock(&card->dapm_mutex);
 	if (ret > 0)
 		soc_dpcm_runtime_update(card);
@@ -2022,13 +2025,16 @@
 }
 
 int snd_soc_dapm_mixer_update_power(struct snd_soc_dapm_context *dapm,
-	struct snd_kcontrol *kcontrol, int connect)
+	struct snd_kcontrol *kcontrol, int connect,
+	struct snd_soc_dapm_update *update)
 {
 	struct snd_soc_card *card = dapm->card;
 	int ret;
 
 	mutex_lock_nested(&card->dapm_mutex, SND_SOC_DAPM_CLASS_RUNTIME);
+	dapm->update = update;
 	ret = soc_dapm_mixer_update_power(dapm, kcontrol, connect);
+	dapm->update = NULL;
 	mutex_unlock(&card->dapm_mutex);
 	if (ret > 0)
 		soc_dpcm_runtime_update(card);