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";
+                };
+        };