doc: a37xx: Introduce pinctrl device tree binding

Reviewed-on: http://vgitil04.il.marvell.com:8080/43289
Tested-by: iSoC Platform CI <ykjenk@marvell.com>
Reviewed-by: Kostya Porotchkin <kostap@marvell.com>
Reviewed-by: Igal Liberman <igall@marvell.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Stefan Roese <sr@denx.de>
Signed-off-by: Ken Ma <make@marvell.com>
Signed-off-by: Stefan Roese <sr@denx.de>

doc/device-tree-bindings/pinctrl/marvell,armada-37xx-pinctrl.txt

@@ -0,0 +1,186 @@
+* Marvell Armada 37xx SoC pin and GPIO controller
+
+Each Armada 37xx SoC comes with two pin and GPIO controllers, one for the
+South Bridge and the other for the North Bridge.
+
+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 registers is for pinctrl/GPIO and the second
+  set is for the interrupt controller
+- interrupts: list of interrupts used 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 7
+ - functions pmic, gpio
+
+group pmic0
+ - pin 6
+ - 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 60-65
+ - functions sdio, gpio
+
+group rgmii
+ - pins 42-53
+ - functions mii, gpio
+
+group pcie1
+ - pins 39-41
+ - functions pcie, gpio
+
+group smi
+ - pins 54-55
+ - functions smi, 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 "gpio" directory for details of gpio-ranges property
+and the common GPIO bindings used by client devices.
+
+Required properties for the GPIO driver under the gpio subnode:
+- interrupts: List of interrupt specifiers 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.
+
+Example:
+pinctrl_sb: pinctrl-sb@18800 {
+	compatible = "marvell,armada3710-sb-pinctrl",
+	"syscon", "simple-mfd";
+	reg = <0x18800 0x100>, <0x18C00 0x20>;
+	gpiosb: gpiosb {
+		#gpio-cells = <2>;
+		gpio-ranges = <&pinctrl_sb 0 0 30>;
+		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";
+	};
+
+	sdio_pins: sdio-pins {
+		groups = "sdio_sb";
+		function = "sdio";
+	};
+
+	pcie_pins: pcie-pins {
+		groups = "pcie1";
+		function = "pcie";
+	};
+};