Input: add generic suspend and resume for input devices

Automatically turn off leds and sound effects as part of suspend
process and restore led state, sounds and repeat rate at resume.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

2 files changed, 64 insertions, 2 deletions

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 7c237e6ac711..b8ed4294fccd 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -11,6 +11,7 @@
  */
 
 #include <linux/init.h>
+#include <linux/types.h>
 #include <linux/input.h>
 #include <linux/module.h>
 #include <linux/random.h>
@@ -514,7 +515,7 @@ static void input_disconnect_device(struct input_dev *dev)
          * that there are no threads in the middle of input_open_device()
          */
         mutex_lock(&dev->mutex);
-        dev->going_away = 1;
+        dev->going_away = true;
         mutex_unlock(&dev->mutex);
 
         spin_lock_irq(&dev->event_lock);
@@ -1259,10 +1260,71 @@ static int input_dev_uevent(struct device *device, struct kobj_uevent_env *env)
         return 0;
 }
 
+#define INPUT_DO_TOGGLE(dev, type, bits, on)                    \
+        do {                                                    \
+                int i;                                          \
+                if (!test_bit(EV_##type, dev->evbit))           \
+                        break;                                  \
+                for (i = 0; i < type##_MAX; i++) {              \
+                        if (!test_bit(i, dev->bits##bit) ||     \
+                            !test_bit(i, dev->bits))            \
+                                continue;                       \
+                        dev->event(dev, EV_##type, i, on);      \
+                }                                               \
+        } while (0)
+
+static void input_dev_reset(struct input_dev *dev, bool activate)
+{
+        if (!dev->event)
+                return;
+
+        INPUT_DO_TOGGLE(dev, LED, led, activate);
+        INPUT_DO_TOGGLE(dev, SND, snd, activate);
+
+        if (activate && test_bit(EV_REP, dev->evbit)) {
+                dev->event(dev, EV_REP, REP_PERIOD, dev->rep[REP_PERIOD]);
+                dev->event(dev, EV_REP, REP_DELAY, dev->rep[REP_DELAY]);
+        }
+}
+
+#ifdef CONFIG_PM
+static int input_dev_suspend(struct device *dev)
+{
+        struct input_dev *input_dev = to_input_dev(dev);
+
+        mutex_lock(&input_dev->mutex);
+        input_dev_reset(input_dev, false);
+        mutex_unlock(&input_dev->mutex);
+
+        return 0;
+}
+
+static int input_dev_resume(struct device *dev)
+{
+        struct input_dev *input_dev = to_input_dev(dev);
+
+        mutex_lock(&input_dev->mutex);
+        input_dev_reset(input_dev, true);
+        mutex_unlock(&input_dev->mutex);
+
+        return 0;
+}
+
+static const struct dev_pm_ops input_dev_pm_ops = {
+        .suspend        = input_dev_suspend,
+        .resume         = input_dev_resume,
+        .poweroff       = input_dev_suspend,
+        .restore        = input_dev_resume,
+};
+#endif /* CONFIG_PM */
+
 static struct device_type input_dev_type = {
         .groups         = input_dev_attr_groups,
         .release        = input_dev_release,
         .uevent         = input_dev_uevent,
+#ifdef CONFIG_PM
+        .pm             = &input_dev_pm_ops,
+#endif
 };
 
 static char *input_nodename(struct device *dev)
diff --git a/include/linux/input.h b/include/linux/input.h
index 8b3bc3e0d146..0ccfc30cd40f 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -1123,7 +1123,7 @@ struct input_dev {
         struct mutex mutex;
 
         unsigned int users;
-        int going_away;
+        bool going_away;
 
         struct device dev;