rtc: DS1374 wakeup support

Wakeup support implementation.

Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c
index a150418..a5b0fc0 100644
--- a/drivers/rtc/rtc-ds1374.c
+++ b/drivers/rtc/rtc-ds1374.c
@@ -429,12 +429,33 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int ds1374_suspend(struct i2c_client *client, pm_message_t state)
+{
+	if (client->irq >= 0 && device_may_wakeup(&client->dev))
+		enable_irq_wake(client->irq);
+	return 0;
+}
+
+static int ds1374_resume(struct i2c_client *client)
+{
+	if (client->irq >= 0 && device_may_wakeup(&client->dev))
+		disable_irq_wake(client->irq);
+	return 0;
+}
+#else
+#define ds1374_suspend	NULL
+#define ds1374_resume	NULL
+#endif
+
 static struct i2c_driver ds1374_driver = {
 	.driver = {
 		.name = "rtc-ds1374",
 		.owner = THIS_MODULE,
 	},
 	.probe = ds1374_probe,
+	.suspend = ds1374_suspend,
+	.resume = ds1374_resume,
 	.remove = __devexit_p(ds1374_remove),
 	.id_table = ds1374_id,
 };