iio: sx9500: add final devicetree support

This makes sx9500 driver usable on devicetree based platforms too.
Signed-off-by: NChristoph Fritz <chf.fritz@googlemail.com>
Reviewed-by: NFabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: NVlad Dogaru <ddvlad@gmail.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Documentation/devicetree/bindings/iio/proximity/sx9500.txt

+Semtech's SX9500 capacitive proximity button device driver
+
+Required properties:
+	- compatible: must be "semtech,sx9500"
+	- reg: i2c address where to find the device
+	- interrupt-parent : should be the phandle for the interrupt controller
+	- interrupts : the sole interrupt generated by the device
+
+	Refer to interrupt-controller/interrupts.txt for generic
+	interrupt client node bindings.
+
+Optional properties:
+	- reset-gpios: Reference to the GPIO connected to the device's active
+	  low reset pin.
+
+Example:
+
+sx9500@28 {
+	compatible = "semtech,sx9500";
+	reg = <0x28>;
+	interrupt-parent = <&gpio2>;
+	interrupts = <16 IRQ_TYPE_LEVEL_LOW>;
+	reset-gpios = <&gpio2 10 GPIO_ACTIVE_LOW>;
+};

drivers/iio/proximity/sx9500.c

@@ -1025,6 +1025,12 @@ static const struct acpi_device_id sx9500_acpi_match[] = {
 };
 MODULE_DEVICE_TABLE(acpi, sx9500_acpi_match);
 
+static const struct of_device_id sx9500_of_match[] = {
+	{ .compatible = "semtech,sx9500", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sx9500_of_match);
+
 static const struct i2c_device_id sx9500_id[] = {
 	{"sx9500", 0},
 	{ },
@@ -1035,6 +1041,7 @@ static struct i2c_driver sx9500_driver = {
 	.driver = {
 		.name	= SX9500_DRIVER_NAME,
 		.acpi_match_table = ACPI_PTR(sx9500_acpi_match),
+		.of_match_table = of_match_ptr(sx9500_of_match),
 		.pm = &sx9500_pm_ops,
 	},
 	.probe		= sx9500_probe,