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-rw-r--r--Documentation/devicetree/bindings/gpio/gpio_lpc32xx.txt43
-rw-r--r--Documentation/gpio.txt3
2 files changed, 46 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 0000000..4981936
--- /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";
+ };
+ };
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
index 620a078..e08a883 100644
--- a/Documentation/gpio.txt
+++ b/Documentation/gpio.txt
@@ -322,6 +322,9 @@ where 'flags' is currently defined to specify the following properties:
* GPIOF_OPEN_DRAIN - gpio pin is open drain type.
* GPIOF_OPEN_SOURCE - gpio pin is open source type.
+ * GPIOF_EXPORT_DIR_FIXED - export gpio to sysfs, keep direction
+ * GPIOF_EXPORT_DIR_CHANGEABLE - also export, allow changing direction
+
since GPIOF_INIT_* are only valid when configured as output, so group valid
combinations as: