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+* Freescale IMX27 IOMUX Controller
+
+Required properties:
+- compatible: "fsl,imx27-iomuxc"
+
+The iomuxc driver node should define subnodes containing of pinctrl configuration subnodes.
+
+Required properties for pin configuration node:
+- fsl,pins: three integers array, represents a group of pins mux and config
+ setting. The format is fsl,pins = <PIN MUX_ID CONFIG>.
+
+ PIN is an integer between 0 and 0xbf. imx27 has 6 ports with 32 configurable
+ configurable pins each. PIN is PORT * 32 + PORT_PIN, PORT_PIN is the pin
+ number on the specific port (between 0 and 31).
+
+ MUX_ID is
+ function + (direction << 2) + (gpio_oconf << 4) + (gpio_iconfa << 8) + (gpio_iconfb << 10)
+
+ function value is used to select the pin function.
+ Possible values:
+ 0 - Primary function
+ 1 - Alternate function
+ 2 - GPIO
+ Registers: GIUS (GPIO In Use), GPR (General Purpose Register)
+
+ direction defines the data direction of the pin.
+ Possible values:
+ 0 - Input
+ 1 - Output
+ Register: DDIR
+
+ gpio_oconf configures the gpio submodule output signal. This does not
+ have any effect unless GPIO function is selected. A/B/C_IN are output
+ signals of function blocks A,B and C. Specific function blocks are
+ described in the reference manual.
+ Possible values:
+ 0 - A_IN
+ 1 - B_IN
+ 2 - C_IN
+ 3 - Data Register
+ Registers: OCR1, OCR2
+
+ gpio_iconfa/b configures the gpio submodule input to functionblocks A and
+ B. GPIO function should be selected if this is configured.
+ Possible values:
+ 0 - GPIO_IN
+ 1 - Interrupt Status Register
+ 2 - Pulldown
+ 3 - Pullup
+ Registers ICONFA1, ICONFA2, ICONFB1 and ICONFB2
+
+ CONFIG can be 0 or 1, meaning Pullup disable/enable.
+
+
+The iomux controller has gpio child nodes which are embedded in the iomux
+control registers. They have to be defined as child nodes of the iomux device
+node. If gpio subnodes are defined "#address-cells", "#size-cells" and "ranges"
+properties for the iomux device node are required.
+
+Example:
+
+iomuxc: iomuxc@10015000 {
+ compatible = "fsl,imx27-iomuxc";
+ reg = <0x10015000 0x600>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ gpio1: gpio@10015000 {
+ ...
+ };
+
+ ...
+
+ uart {
+ pinctrl_uart1: uart-1 {
+ fsl,pins = <
+ 0x8c 0x004 0x0 /* UART1_TXD__UART1_TXD */
+ 0x8d 0x000 0x0 /* UART1_RXD__UART1_RXD */
+ 0x8e 0x004 0x0 /* UART1_CTS__UART1_CTS */
+ 0x8f 0x000 0x0 /* UART1_RTS__UART1_RTS */
+ >;
+ };
+
+ ...
+ };
+};
+
+
+For convenience there are macros defined in imx27-pinfunc.h which provide PIN
+and MUX_ID. They are structured as MX27_PAD_<Pad name>__<Signal name>. The names
+are defined in the i.MX27 reference manual.
+
+The above example using macros:
+
+iomuxc: iomuxc@10015000 {
+ compatible = "fsl,imx27-iomuxc";
+ reg = <0x10015000 0x600>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ gpio1: gpio@10015000 {
+ ...
+ };
+
+ ...
+
+ uart {
+ pinctrl_uart1: uart-1 {
+ fsl,pins = <
+ MX27_PAD_UART1_TXD__UART1_TXD 0x0
+ MX27_PAD_UART1_RXD__UART1_RXD 0x0
+ MX27_PAD_UART1_CTS__UART1_CTS 0x0
+ MX27_PAD_UART1_RTS__UART1_RTS 0x0
+ >;
+ };
+
+ ...
+ };
+};