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-rw-r--r--Documentation/powerpc/dts-bindings/gpio/gpio.txt50
-rw-r--r--Documentation/powerpc/dts-bindings/gpio/led.txt17
-rw-r--r--Documentation/powerpc/dts-bindings/gpio/mdio.txt19
3 files changed, 85 insertions, 1 deletions
diff --git a/Documentation/powerpc/dts-bindings/gpio/gpio.txt b/Documentation/powerpc/dts-bindings/gpio/gpio.txt
new file mode 100644
index 00000000000..edaa84d288a
--- /dev/null
+++ b/Documentation/powerpc/dts-bindings/gpio/gpio.txt
@@ -0,0 +1,50 @@
+Specifying GPIO information for devices
+============================================
+
+1) gpios property
+-----------------
+
+Nodes that makes use of GPIOs should define them using `gpios' property,
+format of which is: <&gpio-controller1-phandle gpio1-specifier
+ &gpio-controller2-phandle gpio2-specifier
+ 0 /* holes are permitted, means no GPIO 3 */
+ &gpio-controller4-phandle gpio4-specifier
+ ...>;
+
+Note that gpio-specifier length is controller dependent.
+
+gpio-specifier may encode: bank, pin position inside the bank,
+whether pin is open-drain and whether pin is logically inverted.
+
+Example of the node using GPIOs:
+
+ node {
+ gpios = <&qe_pio_e 18 0>;
+ };
+
+In this example gpio-specifier is "18 0" and encodes GPIO pin number,
+and empty GPIO flags as accepted by the "qe_pio_e" gpio-controller.
+
+2) gpio-controller nodes
+------------------------
+
+Every GPIO controller node must have #gpio-cells property defined,
+this information will be used to translate gpio-specifiers.
+
+Example of two SOC GPIO banks defined as gpio-controller nodes:
+
+ qe_pio_a: gpio-controller@1400 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-a", "fsl,qe-pario-bank";
+ reg = <0x1400 0x18>;
+ gpio-controller;
+ };
+
+ qe_pio_e: gpio-controller@1460 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
+ reg = <0x1460 0x18>;
+ gpio-controller;
+ };
+
+
diff --git a/Documentation/powerpc/dts-bindings/gpio/led.txt b/Documentation/powerpc/dts-bindings/gpio/led.txt
index 4fe14deedc0..064db928c3c 100644
--- a/Documentation/powerpc/dts-bindings/gpio/led.txt
+++ b/Documentation/powerpc/dts-bindings/gpio/led.txt
@@ -16,10 +16,17 @@ LED sub-node properties:
string defining the trigger assigned to the LED. Current triggers are:
"backlight" - LED will act as a back-light, controlled by the framebuffer
system
- "default-on" - LED will turn on
+ "default-on" - LED will turn on, but see "default-state" below
"heartbeat" - LED "double" flashes at a load average based rate
"ide-disk" - LED indicates disk activity
"timer" - LED flashes at a fixed, configurable rate
+- default-state: (optional) The initial state of the LED. Valid
+ values are "on", "off", and "keep". If the LED is already on or off
+ and the default-state property is set the to same value, then no
+ glitch should be produced where the LED momentarily turns off (or
+ on). The "keep" setting will keep the LED at whatever its current
+ state is, without producing a glitch. The default is off if this
+ property is not present.
Examples:
@@ -30,14 +37,22 @@ leds {
gpios = <&mcu_pio 0 1>; /* Active low */
linux,default-trigger = "ide-disk";
};
+
+ fault {
+ gpios = <&mcu_pio 1 0>;
+ /* Keep LED on if BIOS detected hardware fault */
+ default-state = "keep";
+ };
};
run-control {
compatible = "gpio-leds";
red {
gpios = <&mpc8572 6 0>;
+ default-state = "off";
};
green {
gpios = <&mpc8572 7 0>;
+ default-state = "on";
};
}
diff --git a/Documentation/powerpc/dts-bindings/gpio/mdio.txt b/Documentation/powerpc/dts-bindings/gpio/mdio.txt
new file mode 100644
index 00000000000..bc954952901
--- /dev/null
+++ b/Documentation/powerpc/dts-bindings/gpio/mdio.txt
@@ -0,0 +1,19 @@
+MDIO on GPIOs
+
+Currently defined compatibles:
+- virtual,gpio-mdio
+
+MDC and MDIO lines connected to GPIO controllers are listed in the
+gpios property as described in section VIII.1 in the following order:
+
+MDC, MDIO.
+
+Example:
+
+mdio {
+ compatible = "virtual,mdio-gpio";
+ #address-cells = <1>;
+ #size-cells = <0>;
+ gpios = <&qe_pio_a 11
+ &qe_pio_c 6>;
+};