Input: release pressed keys when resuming device

As the kernel has no way to know whether a key was released
while the system was asleep, keys need to be reported released
as the system is resumed, lest autorepeat set in.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/input.c b/drivers/input/input.c
index 9c79bd5..240ad39 100644 (file)
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -528,12 +528,30 @@ void input_close_device(struct input_handle *handle)
 EXPORT_SYMBOL(input_close_device);
 
 /*
+ * Simulate keyup events for all keys that are marked as pressed.
+ * The function must be called with dev->event_lock held.
+ */
+static void input_dev_release_keys(struct input_dev *dev)
+{
+       int code;
+
+       if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
+               for (code = 0; code <= KEY_MAX; code++) {
+                       if (is_event_supported(code, dev->keybit, KEY_MAX) &&
+                           __test_and_clear_bit(code, dev->key)) {
+                               input_pass_event(dev, EV_KEY, code, 0);
+                       }
+               }
+               input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
+       }
+}
+
+/*
  * Prepare device for unregistering
  */
 static void input_disconnect_device(struct input_dev *dev)
 {
        struct input_handle *handle;
-       int code;
 
        /*
         * Mark device as going away. Note that we take dev->mutex here
@@ -552,15 +570,7 @@ static void input_disconnect_device(struct input_dev *dev)
         * generate events even after we done here but they will not
         * reach any handlers.
         */
-       if (is_event_supported(EV_KEY, dev->evbit, EV_MAX)) {
-               for (code = 0; code <= KEY_MAX; code++) {
-                       if (is_event_supported(code, dev->keybit, KEY_MAX) &&
-                           __test_and_clear_bit(code, dev->key)) {
-                               input_pass_event(dev, EV_KEY, code, 0);
-                       }
-               }
-               input_pass_event(dev, EV_SYN, SYN_REPORT, 1);
-       }
+       input_dev_release_keys(dev);
 
        list_for_each_entry(handle, &dev->h_list, d_node)
                handle->open = 0;
@@ -1433,6 +1443,15 @@ static int input_dev_resume(struct device *dev)
 
        mutex_lock(&input_dev->mutex);
        input_dev_reset(input_dev, true);
+
+       /*
+        * Keys that have been pressed at suspend time are unlikely
+        * to be still pressed when we resume.
+        */
+       spin_lock_irq(&input_dev->event_lock);
+       input_dev_release_keys(input_dev);
+       spin_unlock_irq(&input_dev->event_lock);
+
        mutex_unlock(&input_dev->mutex);
 
        return 0;