mfd: Add ability to wake the system for 88pm860x

For 88pm860x pmic, it can wake the system from low power mode by irq,
its sub-devs like RTC and onkey can be enabled for this usage.

Signed-off-by: Jett.Zhou <jtzhou@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/rtc/rtc-88pm860x.c b/drivers/rtc/rtc-88pm860x.c
index f04761e..afee0e8 100644
--- a/drivers/rtc/rtc-88pm860x.c
+++ b/drivers/rtc/rtc-88pm860x.c
@@ -376,6 +376,9 @@
 	INIT_DELAYED_WORK(&info->calib_work, calibrate_vrtc_work);
 	schedule_delayed_work(&info->calib_work, VRTC_CALIB_INTERVAL);
 #endif	/* VRTC_CALIBRATION */
+
+	device_init_wakeup(&pdev->dev, 1);
+
 	return 0;
 out_rtc:
 	free_irq(info->irq, info);
@@ -401,10 +404,34 @@
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int pm860x_rtc_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
+
+	if (device_may_wakeup(dev))
+		chip->wakeup_flag |= 1 << PM8607_IRQ_RTC;
+	return 0;
+}
+static int pm860x_rtc_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
+
+	if (device_may_wakeup(dev))
+		chip->wakeup_flag &= ~(1 << PM8607_IRQ_RTC);
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(pm860x_rtc_pm_ops, pm860x_rtc_suspend, pm860x_rtc_resume);
+
 static struct platform_driver pm860x_rtc_driver = {
 	.driver		= {
 		.name	= "88pm860x-rtc",
 		.owner	= THIS_MODULE,
+		.pm	= &pm860x_rtc_pm_ops,
 	},
 	.probe		= pm860x_rtc_probe,
 	.remove		= __devexit_p(pm860x_rtc_remove),