pinctrl: dt-bindings: Add documentation for Armada 37xx pin controllers

Document the device tree binding for the pin controllers found on the
Armada 37xx SoCs.

Update the binding documention of the xtal clk which is a subnode of this
syscon node.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
[Fixed gpios node]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/clock/armada3700-xtal-clock.txt

@@ -5,6 +5,7 @@ reading the gpio latch register.
 
 This node must be a subnode of the node exposing the register address
 of the GPIO block where the gpio latch is located.
+See Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
 
 Required properties:
 - compatible : shall be one of the following:
@@ -16,9 +17,9 @@ Optional properties:
 	output names ("xtal")
 
 Example:
-gpio1: gpio@13800 {
-	compatible = "marvell,armada-3700-gpio", "syscon", "simple-mfd";
-	reg = <0x13800 0x1000>;
+pinctrl_nb: pinctrl-nb@13800 {
+	compatible = "armada3710-nb-pinctrl", "syscon", "simple-mfd";
+	reg = <0x13800 0x100>, <0x13C00 0x20>;
 
 	xtalclk: xtal-clk {
 		compatible = "marvell,armada-3700-xtal-clock";

Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt

+* Marvell Armada 37xx SoC pin and gpio controller
+
+Each Armada 37xx SoC come with two pin and gpio controller one for the
+south bridge and the other for the north bridge.
+
+Inside this set of register the gpio latch allows exposing some
+configuration of the SoC and especially the clock frequency of the
+xtal. Hence, this node is a represent as syscon allowing sharing the
+register between multiple hardware block.
+
+GPIO and pin controller:
+------------------------
+
+Main node:
+
+Refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning
+of the phrase "pin configuration node".
+
+Required properties for pinctrl driver:
+
+- compatible:	"marvell,armada3710-sb-pinctrl", "syscon, "simple-mfd"
+		for the south bridge
+		"marvell,armada3710-nb-pinctrl", "syscon, "simple-mfd"
+		for the north bridge
+- reg: The first set of register are for pinctrl/gpio and the second
+  set for the interrupt controller
+- interrupts: list of the interrupt use by the gpio
+
+Available groups and functions for the North bridge:
+
+group: jtag
+ - pins 20-24
+ - functions jtag, gpio
+
+group sdio0
+ - pins 8-10
+ - functions sdio, gpio
+
+group emmc_nb
+ - pins 27-35
+ - functions emmc, gpio
+
+group pwm0
+ - pin 11 (GPIO1-11)
+ - functions pwm, gpio
+
+group pwm1
+ - pin 12
+ - functions pwm, gpio
+
+group pwm2
+ - pin 13
+ - functions pwm, gpio
+
+group pwm3
+ - pin 14
+ - functions pwm, gpio
+
+group pmic1
+ - pin 17
+ - functions pmic, gpio
+
+group pmic0
+ - pin 16
+ - functions pmic, gpio
+
+group i2c2
+ - pins 2-3
+ - functions i2c, gpio
+
+group i2c1
+ - pins 0-1
+ - functions i2c, gpio
+
+group spi_cs1
+ - pin 17
+ - functions spi, gpio
+
+group spi_cs2
+ - pin 18
+ - functions spi, gpio
+
+group spi_cs3
+ - pin 19
+ - functions spi, gpio
+
+group onewire
+ - pin 4
+ - functions onewire, gpio
+
+group uart1
+ - pins 25-26
+ - functions uart, gpio
+
+group spi_quad
+ - pins 15-16
+ - functions spi, gpio
+
+group uart_2
+ - pins 9-10
+ - functions uart, gpio
+
+Available groups and functions for the South bridge:
+
+group usb32_drvvbus0
+ - pin 36
+ - functions drvbus, gpio
+
+group usb2_drvvbus1
+ - pin 37
+ - functions drvbus, gpio
+
+group sdio_sb
+ - pins 60-64
+ - functions sdio, gpio
+
+group rgmii
+ - pins 42-55
+ - functions mii, gpio
+
+group pcie1
+ - pins 39-40
+ - functions pcie, gpio
+
+group ptp
+ - pins 56-58
+ - functions ptp, gpio
+
+group ptp_clk
+ - pin 57
+ - functions ptp, mii
+
+group ptp_trig
+ - pin 58
+ - functions ptp, mii
+
+group mii_col
+ - pin 59
+ - functions mii, mii_err
+
+GPIO subnode:
+
+Please refer to gpio.txt in this directory for details of gpio-ranges property
+and the common GPIO bindings used by client devices.
+
+Required properties for gpio driver under the gpio subnode:
+- interrupts: List of interrupt specifier for the controllers interrupt.
+- gpio-controller: Marks the device node as a gpio controller.
+- #gpio-cells: Should be 2. The first cell is the GPIO 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.
+- gpio-ranges: Range of pins managed by the GPIO controller.
+
+Xtal Clock bindings for Marvell Armada 37xx SoCs
+------------------------------------------------
+
+see Documentation/devicetree/bindings/clock/armada3700-xtal-clock.txt
+
+
+Example:
+pinctrl_sb: pinctrl-sb@18800 {
+	compatible = "marvell,armada3710-sb-pinctrl", "syscon", "simple-mfd";
+	reg = <0x18800 0x100>, <0x18C00 0x20>;
+	gpio {
+		#gpio-cells = <2>;
+		gpio-ranges = <&pinctrl_sb 0 0 29>;
+		gpio-controller;
+		interrupts =
+		<GIC_SPI 160 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 159 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 158 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 157 IRQ_TYPE_LEVEL_HIGH>,
+		<GIC_SPI 156 IRQ_TYPE_LEVEL_HIGH>;
+	};
+
+	rgmii_pins: mii-pins {
+		groups = "rgmii";
+		function = "mii";
+	};
+
+};