Input: twl4030-pwrbutton - add device tree support

Add device tree support for twl4030 power button driver.

Adding device tree support involved converting the
driver to module_platform_driver().
Signed-off-by: Sebastian Reichel <sre@debian.org>
Acked-by: Kumar Gala <galak@codeaurora.org>
Tested-by: Florian Vaussard <florian.vaussard@epfl.ch>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/twl4030-pwrbutton.txt

+Texas Instruments TWL family (twl4030) pwrbutton module
+
+This module is part of the TWL4030. For more details about the whole
+chip see Documentation/devicetree/bindings/mfd/twl-familly.txt.
+
+This module provides a simple power button event via an Interrupt.
+
+Required properties:
+- compatible: should be one of the following
+   - "ti,twl4030-pwrbutton": For controllers compatible with twl4030
+- interrupts: should be one of the following
+   - <8>: For controllers compatible with twl4030
+
+Example:
+
+&twl {
+	twl_pwrbutton: pwrbutton {
+		compatible = "ti,twl4030-pwrbutton";
+		interrupts = <8>;
+	};
+};

drivers/input/misc/twl4030-pwrbutton.c

@@ -52,7 +52,7 @@ static irqreturn_t powerbutton_irq(int irq, void *_pwr)
 	return IRQ_HANDLED;
 }
 
-static int __init twl4030_pwrbutton_probe(struct platform_device *pdev)
+static int twl4030_pwrbutton_probe(struct platform_device *pdev)
 {
 	struct input_dev *pwr;
 	int irq = platform_get_irq(pdev, 0);
@@ -106,16 +106,24 @@ static int __exit twl4030_pwrbutton_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id twl4030_pwrbutton_dt_match_table[] = {
+       { .compatible = "ti,twl4030-pwrbutton" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, twl4030_pwrbutton_dt_match_table);
+#endif
+
 static struct platform_driver twl4030_pwrbutton_driver = {
+	.probe		= twl4030_pwrbutton_probe,
 	.remove		= __exit_p(twl4030_pwrbutton_remove),
 	.driver		= {
 		.name	= "twl4030_pwrbutton",
 		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(twl4030_pwrbutton_dt_match_table),
 	},
 };
-
-module_platform_driver_probe(twl4030_pwrbutton_driver,
-			twl4030_pwrbutton_probe);
+module_platform_driver(twl4030_pwrbutton_driver);
 
 MODULE_ALIAS("platform:twl4030_pwrbutton");
 MODULE_DESCRIPTION("Triton2 Power Button");