Input: mma8450 - add device tree probe support

It adds device tree probe support for mma8450 driver.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Eric Miao <eric.miao@linaro.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

Documentation/devicetree/bindings/input/fsl-mma8450.txt

+* Freescale MMA8450 3-Axis Accelerometer
+
+Required properties:
+- compatible : "fsl,mma8450".
+
+Example:
+
+accelerometer: mma8450@1c {
+	compatible = "fsl,mma8450";
+	reg = <0x1c>;
+};

drivers/input/misc/mma8450.c

@@ -24,6 +24,7 @@
 #include <linux/delay.h>
 #include <linux/i2c.h>
 #include <linux/input-polldev.h>
+#include <linux/of_device.h>
 
 #define MMA8450_DRV_NAME	"mma8450"
 
@@ -229,10 +230,17 @@ static const struct i2c_device_id mma8450_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, mma8450_id);
 
+static const struct of_device_id mma8450_dt_ids[] = {
+	{ .compatible = "fsl,mma8450", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, mma8450_dt_ids);
+
 static struct i2c_driver mma8450_driver = {
 	.driver = {
 		.name	= MMA8450_DRV_NAME,
 		.owner	= THIS_MODULE,
+		.of_match_table = mma8450_dt_ids,
 	},
 	.probe		= mma8450_probe,
 	.remove		= __devexit_p(mma8450_remove),