From fc9bd9022e8d5863f3efce34cc38cb0c6187271c Mon Sep 17 00:00:00 2001
From: Vaibhav Hiremath <hvaibhav@ti.com>
Date: Mon, 17 Dec 2012 16:02:18 -0800
Subject: [PATCH] rtc: omap: add runtime pm support

OMAP1 RTC driver is used in multiple devices like, OMAPL138 and AM33XX.
Driver currently doesn't handle any clocks, which may be right for OMAP1
architecture but in case of AM33XX, the clock/module needs to be enabled
in order to access the registers.

So convert this driver to runtime pm, which internally handles rest.

[afzal@ti.com: handle error path]
Signed-off-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Acked-by: Sekhar Nori <nsekhar@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Daniel Mack <zonque@gmail.com>
Cc: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 drivers/rtc/rtc-omap.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index dff9ff476b0d..600971407aac 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -22,6 +22,7 @@
 #include <linux/platform_device.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/pm_runtime.h>
 
 #include <asm/io.h>
 
@@ -364,6 +365,10 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 		goto fail;
 	}
 
+	/* Enable the clock/module so that we can access the registers */
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
 	id_entry = platform_get_device_id(pdev);
 	if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER)) {
 		rtc_writel(KICK0_VALUE, OMAP_RTC_KICK0_REG);
@@ -448,6 +453,8 @@ fail1:
 fail0:
 	if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER))
 		rtc_writel(0, OMAP_RTC_KICK0_REG);
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
 	iounmap(rtc_base);
 fail:
 	release_mem_region(mem->start, resource_size(mem));
@@ -474,6 +481,11 @@ static int __exit omap_rtc_remove(struct platform_device *pdev)
 	rtc_device_unregister(rtc);
 	if (id_entry && (id_entry->driver_data & OMAP_RTC_HAS_KICKER))
 		rtc_writel(0, OMAP_RTC_KICK0_REG);
+
+	/* Disable the clock/module */
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
 	iounmap(rtc_base);
 	release_mem_region(mem->start, resource_size(mem));
 	return 0;
@@ -496,11 +508,17 @@ static int omap_rtc_suspend(struct platform_device *pdev, pm_message_t state)
 	else
 		rtc_write(0, OMAP_RTC_INTERRUPTS_REG);
 
+	/* Disable the clock/module */
+	pm_runtime_put_sync(&pdev->dev);
+
 	return 0;
 }
 
 static int omap_rtc_resume(struct platform_device *pdev)
 {
+	/* Enable the clock/module so that we can access the registers */
+	pm_runtime_get_sync(&pdev->dev);
+
 	if (device_may_wakeup(&pdev->dev))
 		disable_irq_wake(omap_rtc_alarm);
 	else
-- 
2.20.1