gpio/lpc32xx: Add device tree support

This patch adds device tree support for gpio-lpc32xx.c.

To register the various GPIO banks as (struct) gpio_chips via the same DT
gpio-controller, we utilize the adjusted of_xlate API to manipulate the
actually used struct gpio_chip.

Signed-off-by: Roland Stigge <stigge@antcom.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 43 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt b/Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt
new file mode 100644
index 000000000000..49819367a011
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt
@@ -0,0 +1,43 @@
+NXP LPC32xx SoC GPIO controller
+
+Required properties:
+- compatible: must be "nxp,lpc3220-gpio"
+- reg: Physical base address and length of the controller's registers.
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells: Should be 3:
+   1) bank:
+      0: GPIO P0
+      1: GPIO P1
+      2: GPIO P2
+      3: GPIO P3
+      4: GPI P3
+      5: GPO P3
+   2) pin number
+   3) optional parameters:
+      - bit 0 specifies polarity (0 for normal, 1 for inverted)
+- reg: Index of the GPIO group
+
+Example:
+
+	gpio: gpio@40028000 {
+		compatible = "nxp,lpc3220-gpio";
+		reg = <0x40028000 0x1000>;
+		gpio-controller;
+		#gpio-cells = <3>; /* bank, pin, flags */
+	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led0 {
+			gpios = <&gpio 5 1 1>; /* GPO_P3 1, active low */
+			linux,default-trigger = "heartbeat";
+			default-state = "off";
+		};
+
+		led1 {
+			gpios = <&gpio 5 14 1>; /* GPO_P3 14, active low */
+			linux,default-trigger = "timer";
+			default-state = "off";
+		};
+	};