Input: Hold wake lock while event queue is not empty.
Allows userspace code to process input events while
the device appears to be asleep.
Signed-off-by: Arve Hjønnevåg <arve@android.com>
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index be0921e..1f571d7 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -23,6 +23,7 @@
#include <linux/input.h>
#include <linux/major.h>
#include <linux/device.h>
+#include <linux/wakelock.h>
#include "input-compat.h"
struct evdev {
@@ -43,6 +44,7 @@
unsigned int tail;
unsigned int packet_head; /* [future] position of the first element of next packet */
spinlock_t buffer_lock; /* protects access to buffer, head and tail */
+ struct wake_lock wake_lock;
struct fasync_struct *fasync;
struct evdev *evdev;
struct list_head node;
@@ -59,6 +61,7 @@
/* Interrupts are disabled, just acquire the lock. */
spin_lock(&client->buffer_lock);
+ wake_lock_timeout(&client->wake_lock, 5 * HZ);
client->buffer[client->head++] = *event;
client->head &= client->bufsize - 1;
@@ -254,6 +257,7 @@
mutex_unlock(&evdev->mutex);
evdev_detach_client(evdev, client);
+ wake_lock_destroy(&client->wake_lock);
kfree(client);
evdev_close_device(evdev);
@@ -305,6 +309,7 @@
client->bufsize = bufsize;
spin_lock_init(&client->buffer_lock);
+ wake_lock_init(&client->wake_lock, WAKE_LOCK_SUSPEND, "evdev");
client->evdev = evdev;
evdev_attach_client(evdev, client);
@@ -372,6 +377,8 @@
if (have_event) {
*event = client->buffer[client->tail++];
client->tail &= client->bufsize - 1;
+ if (client->head == client->tail)
+ wake_unlock(&client->wake_lock);
}
spin_unlock_irq(&client->buffer_lock);