[PATCH 4/6] i2c: davinci: Add suspend/resume support

[Kevin Hilman <khilman-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>]

From: Chaithrika U S <chaithrika-l0cyMroinI0@public.gmane.org>

Add suspend and resume callbacks to DaVinci I2C driver.
This has been tested on DA850/OMAP-L138 EVM. The SoC specific
suspend-to-RAM support patch series [1] is needed to test this feature.

[1] http://linux.davincidsp.com/pipermail/davinci-linux-open-source/
2009-November/016958.html

Signed-off-by: Chaithrika U S <chaithrika-l0cyMroinI0@public.gmane.org>
Acked-by: Kevin Hilman <khilman-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
---
 drivers/i2c/busses/i2c-davinci.c |   36 ++++++++++++++++++++++++++++++++++++
 1 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index aacef7b..66b07bf 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -643,6 +643,41 @@ static int davinci_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int davinci_i2c_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+	/* put I2C into reset */
+	davinci_i2c_reset_ctrl(i2c_dev, 0);
+	clk_disable(i2c_dev->clk);
+
+	return 0;
+}
+
+static int davinci_i2c_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct davinci_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+	clk_enable(i2c_dev->clk);
+	/* take I2C out of reset */
+	davinci_i2c_reset_ctrl(i2c_dev, 1);
+
+	return 0;
+}
+
+static struct dev_pm_ops davinci_i2c_pm = {
+	.suspend        = davinci_i2c_suspend,
+	.resume         = davinci_i2c_resume,
+};
+
+#define davinci_i2c_pm_ops (&davinci_i2c_pm)
+#else
+#define davinci_i2c_pm_ops NULL
+#endif
+
 /* work with hotplug and coldplug */
 MODULE_ALIAS("platform:i2c_davinci");
 
@@ -652,6 +687,7 @@ static struct platform_driver davinci_i2c_driver = {
 	.driver		= {
 		.name	= "i2c_davinci",
 		.owner	= THIS_MODULE,
+		.pm	= davinci_i2c_pm_ops,
 	},
 };
 
-- 
1.6.6