[PATCH v4 2/2] dt-bindings: document gpio-mt7621 bindings

Sergio Paracuellos
2018-07-05T13:43:11Z

Add a devicetree binding documentation for the mt7621 gpio.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: NeilBrown <neil@brown.name>
---
.../bindings/gpio/mediatek,mt7621-gpio.txt | 35 ++++++++++++++++++++++
1 file changed, 35 insertions(+)
create mode 100644 Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.txt

diff --git a/Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.txt b/Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.txt
new file mode 100644
index 0000000..ba45558
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/mediatek,mt7621-gpio.txt
@@ -0,0 +1,35 @@
+Mediatek MT7621 SoC GPIO controller bindings
+
+The IP core used inside these SoCs has 3 banks of 32 GPIOs each.
+The registers of all the banks are interwoven inside one single IO range.
+We load one GPIO controller instance per bank. Also the GPIO controller can receive
+interrupts on any of the GPIOs, either edge or level. It then interrupts the CPU
+using GIC INT12.
+
+Required properties for the top level node:
+- #gpio-cells : Should be two. The first cell is the GPIO pin number and the
+ second cell specifies GPIO flags, as defined in <dt-bindings/gpio/gpio.h>.
+ Only the GPIO_ACTIVE_HIGH and GPIO_ACTIVE_LOW flags are supported.
+- #interrupt-cells : Specifies the number of cells needed to encode an
+ interrupt. Should be 2. The first cell defines the interrupt number,
+ the second encodes the triger flags encoded as described in
+ Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+- compatible:
+ - "mediatek,mt7621-gpio" for Mediatek controllers
+- reg : Physical base address and length of the controller's registers
+- interrupt-parent : phandle of the parent interrupt controller.
+- interrupts : Interrupt specifier for the controllers interrupt.
+- interrupt-controller : Mark the device node as an interrupt controller.
+- gpio-controller : Marks the device node as a GPIO controller.
+
+Example:
+ gpio@600 {
+ #gpio-cells = <2>;
+ #interrupt-cells = <2>;
+ compatible = "mediatek,mt7621-gpio";
+ gpio-controller;
+ interrupt-controller;
+ reg = <0x600 0x100>;
+ interrupt-parent = <&gic>;
+ interrupts = <GIC_SHARED 12 IRQ_TYPE_LEVEL_HIGH>;
+ };
--
2.7.4