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>

2 files changed, 13 insertions, 4 deletions

diff --git a/include/sound/soc-dapm.h b/include/sound/soc-dapm.h
index 3717ad089486..e77c6f5a8390 100644
--- a/include/sound/soc-dapm.h
+++ b/include/sound/soc-dapm.h
@@ -333,6 +333,7 @@ struct snd_soc_dapm_route;
 struct snd_soc_dapm_context;
 struct regulator;
 struct snd_soc_dapm_widget_list;
+struct snd_soc_dapm_update;
 
 int dapm_reg_event(struct snd_soc_dapm_widget *w,
                    struct snd_kcontrol *kcontrol, int event);
@@ -392,9 +393,11 @@ void snd_soc_dapm_shutdown(struct snd_soc_card *card);
 
 /* external DAPM widget events */
 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);
 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);
 
 /* dapm sys fs - used by the core */
 int snd_soc_dapm_sys_add(struct device *dev);
diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index 6f8a01bf6ca8..758761146a42 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -1982,13 +1982,16 @@ static int soc_dapm_mux_update_power(struct snd_soc_dapm_context *dapm,
 }
 
 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 @@ static int soc_dapm_mixer_update_power(struct snd_soc_dapm_context *dapm,
 }
 
 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);