pinctrl: dt-binding: Add DT binding documentation for MSM8660

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/devicetree/bindings/pinctrl/qcom,msm8660-pinctrl.txt

+Qualcomm MSM8660 TLMM block
+
+Required properties:
+- compatible: "qcom,msm8660-pinctrl"
+- reg: Should be the base address and length of the TLMM block.
+- interrupts: Should be the parent IRQ of the TLMM block.
+- interrupt-controller: Marks the device node as an interrupt controller.
+- #interrupt-cells: Should be two.
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells : Should be two.
+                The first cell is the gpio pin number and the
+                second cell is used for optional parameters.
+
+Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
+a general description of GPIO and interrupt bindings.
+
+Please 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".
+
+Qualcomm's pin configuration nodes act as a container for an arbitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+pin, a group, or a list of pins or groups. This configuration can include the
+mux function to select on those pin(s)/group(s), and various pin configuration
+parameters, such as pull-up, drive strength, etc.
+
+The name of each subnode is not important; all subnodes should be enumerated
+and processed purely based on their content.
+
+Each subnode only affects those parameters that are explicitly listed. In
+other words, a subnode that lists a mux function but no pin configuration
+parameters implies no information about any pin configuration parameters.
+Similarly, a pin subnode that describes a pullup parameter implies no
+information about e.g. the mux function.
+
+
+The following generic properties as defined in pinctrl-bindings.txt are valid
+to specify in a pin configuration subnode:
+
+ pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength,
+ output-low, output-high.
+
+Non-empty subnodes must specify the 'pins' property.
+
+Valid values for pins are:
+  gpio0-gpio172, sdc3_clk, sdc3_cmd, sdc3_data sdc4_clk, sdc4_cmd, sdc4_data
+
+Valid values for function are:
+  gpio, cam_mclk, dsub, ext_gps, gp_clk_0a, gp_clk_0b, gp_clk_1a, gp_clk_1b,
+  gp_clk_2a, gp_clk_2b, gp_mn, gsbi1, gsbi1_spi_cs1_n, gsbi1_spi_cs2a_n,
+  gsbi1_spi_cs2b_n, gsbi1_spi_cs3_n, gsbi2, gsbi2_spi_cs1_n, gsbi2_spi_cs2_n,
+  gsbi2_spi_cs3_n, gsbi3, gsbi3_spi_cs1_n, gsbi3_spi_cs2_n, gsbi3_spi_cs3_n,
+  gsbi4, gsbi5, gsbi6, gsbi7, gsbi8, gsbi9, gsbi10, gsbi11, gsbi12, hdmi, i2s,
+  lcdc, mdp_vsync, mi2s, pcm, ps_hold, sdc1, sdc2, sdc5, tsif1, tsif2, usb_fs1,
+  usb_fs1_oe_n, usb_fs2, usb_fs2_oe_n, vfe, vsens_alarm,
+
+Example:
+
+	msmgpio: pinctrl@800000 {
+		compatible = "qcom,msm8660-pinctrl";
+		reg = <0x800000 0x4000>;
+
+		gpio-controller;
+		#gpio-cells = <2>;
+		interrupt-controller;
+		#interrupt-cells = <2>;
+		interrupts = <0 16 0x4>;
+
+		pinctrl-names = "default";
+		pinctrl-0 = <&gsbi12_uart>;
+
+		gsbi12_uart: gsbi12-uart {
+			mux {
+				pins = "gpio117", "gpio118";
+				function = "gsbi12";
+			};
+
+			tx {
+				pins = "gpio118";
+				drive-strength = <8>;
+				bias-disable;
+			};
+
+			rx {
+				pins = "gpio117";
+				drive-strength = <2>;
+				bias-pull-up;
+			};
+		};
+	};