ASoC: jack - check status of GPIO-based pins on resume

For GPIO-backed pins that are not configured as wakeup sources, we may
miss change in their state that happens while system is suspended. Let's
use PM notifier to refresh their state upon resume.

Signed-off-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 2b502f6cc6d036be6e25c6834671be1cde2fd8da..1d20abec499579de91c716f348ab269845e55d12 100644 (file)
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -722,6 +722,7 @@ struct snd_soc_jack_gpio {
        /* private: */
        struct snd_soc_jack *jack;
        struct delayed_work work;
+       struct notifier_block pm_notifier;
        struct gpio_desc *desc;
 
        void *data;

diff --git a/sound/soc/soc-jack.c b/sound/soc/soc-jack.c
index fbaa1bb41102f45920f478008070ee53cdbbb6b4..a03dcbb94baf86ba37c22e9dde52b80a16de725b 100644 (file)
--- a/sound/soc/soc-jack.c
+++ b/sound/soc/soc-jack.c
@@ -19,6 +19,7 @@
 #include <linux/workqueue.h>
 #include <linux/delay.h>
 #include <linux/export.h>
+#include <linux/suspend.h>
 #include <trace/events/asoc.h>
 
 /**
@@ -293,6 +294,27 @@ static void gpio_work(struct work_struct *work)
        snd_soc_jack_gpio_detect(gpio);
 }
 
+static int snd_soc_jack_pm_notifier(struct notifier_block *nb,
+                                   unsigned long action, void *data)
+{
+       struct snd_soc_jack_gpio *gpio =
+                       container_of(nb, struct snd_soc_jack_gpio, pm_notifier);
+
+       switch (action) {
+       case PM_POST_SUSPEND:
+       case PM_POST_HIBERNATION:
+       case PM_POST_RESTORE:
+               /*
+                * Use workqueue so we do not have to care about running
+                * concurrently with work triggered by the interrupt handler.
+                */
+               queue_delayed_work(system_power_efficient_wq, &gpio->work, 0);
+               break;
+       }
+
+       return NOTIFY_DONE;
+}
+
 /**
  * snd_soc_jack_add_gpios - Associate GPIO pins with an ASoC jack
  *
@@ -369,6 +391,13 @@ got_gpio:
                                        i, ret);
                }
 
+               /*
+                * Register PM notifier so we do not miss state transitions
+                * happening while system is asleep.
+                */
+               gpios[i].pm_notifier.notifier_call = snd_soc_jack_pm_notifier;
+               register_pm_notifier(&gpios[i].pm_notifier);
+
                /* Expose GPIO value over sysfs for diagnostic purposes */
                gpiod_export(gpios[i].desc, false);
 
@@ -428,6 +457,7 @@ void snd_soc_jack_free_gpios(struct snd_soc_jack *jack, int count,
 
        for (i = 0; i < count; i++) {
                gpiod_unexport(gpios[i].desc);
+               unregister_pm_notifier(&gpios[i].pm_notifier);
                free_irq(gpiod_to_irq(gpios[i].desc), &gpios[i]);
                cancel_delayed_work_sync(&gpios[i].work);
                gpiod_put(gpios[i].desc);