2 files changed, 44 insertions, 0 deletions

diff --git a/include/sound/soc.h b/include/sound/soc.h
index b8bac6ae6244..80dfac162723 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -15,6 +15,7 @@
 
 #include <linux/platform_device.h>
 #include <linux/types.h>
+#include <linux/notifier.h>
 #include <linux/workqueue.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
@@ -261,6 +262,10 @@ int snd_soc_jack_new(struct snd_soc_card *card, const char *id, int type,
 void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask);
 int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
                           struct snd_soc_jack_pin *pins);
+void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
+                                    struct notifier_block *nb);
+void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
+                                      struct notifier_block *nb);
 #ifdef CONFIG_GPIOLIB
 int snd_soc_jack_add_gpios(struct snd_soc_jack *jack, int count,
                         struct snd_soc_jack_gpio *gpios);
@@ -364,6 +369,7 @@ struct snd_soc_jack {
         struct snd_soc_card *card;
         struct list_head pins;
         int status;
+        struct blocking_notifier_head notifier;
 };
 
 /* SoC PCM stream information */
diff --git a/sound/soc/soc-jack.c b/sound/soc/soc-jack.c
index 3c07a94c2e30..f8fd22cc70bc 100644
--- a/sound/soc/soc-jack.c
+++ b/sound/soc/soc-jack.c
@@ -37,6 +37,7 @@ int snd_soc_jack_new(struct snd_soc_card *card, const char *id, int type,
 {
         jack->card = card;
         INIT_LIST_HEAD(&jack->pins);
+        BLOCKING_INIT_NOTIFIER_HEAD(&jack->notifier);
 
         return snd_jack_new(card->codec->card, id, type, &jack->jack);
 }
@@ -93,6 +94,9 @@ void snd_soc_jack_report(struct snd_soc_jack *jack, int status, int mask)
                         snd_soc_dapm_disable_pin(codec, pin->pin);
         }
 
+        /* Report before the DAPM sync to help users updating micbias status */
+        blocking_notifier_call_chain(&jack->notifier, status, NULL);
+
         snd_soc_dapm_sync(codec);
 
         snd_jack_report(jack->jack, status);
@@ -143,6 +147,40 @@ int snd_soc_jack_add_pins(struct snd_soc_jack *jack, int count,
 }
 EXPORT_SYMBOL_GPL(snd_soc_jack_add_pins);
 
+/**
+ * snd_soc_jack_notifier_register - Register a notifier for jack status
+ *
+ * @jack:  ASoC jack
+ * @nb:    Notifier block to register
+ *
+ * Register for notification of the current status of the jack.  Note
+ * that it is not possible to report additional jack events in the
+ * callback from the notifier, this is intended to support
+ * applications such as enabling electrical detection only when a
+ * mechanical detection event has occurred.
+ */
+void snd_soc_jack_notifier_register(struct snd_soc_jack *jack,
+                                    struct notifier_block *nb)
+{
+        blocking_notifier_chain_register(&jack->notifier, nb);
+}
+EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_register);
+
+/**
+ * snd_soc_jack_notifier_unregister - Unregister a notifier for jack status
+ *
+ * @jack:  ASoC jack
+ * @nb:    Notifier block to unregister
+ *
+ * Stop notifying for status changes.
+ */
+void snd_soc_jack_notifier_unregister(struct snd_soc_jack *jack,
+                                      struct notifier_block *nb)
+{
+        blocking_notifier_chain_unregister(&jack->notifier, nb);
+}
+EXPORT_SYMBOL_GPL(snd_soc_jack_notifier_unregister);
+
 #ifdef CONFIG_GPIOLIB
 /* gpio detect */
 static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)