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+Device tree bindings for i.MX Wireless External Interface Module (WEIM)
+
+The term "wireless" does not imply that the WEIM is literally an interface
+without wires. It simply means that this module was originally designed for
+wireless and mobile applications that use low-power technology.
+
+The actual devices are instantiated from the child nodes of a WEIM node.
+
+Required properties:
+
+ - compatible: Should contain one of the following:
+ "fsl,imx1-weim"
+ "fsl,imx27-weim"
+ "fsl,imx51-weim"
+ "fsl,imx50-weim"
+ "fsl,imx6q-weim"
+ - reg: A resource specifier for the register space
+ (see the example below)
+ - clocks: the clock, see the example below.
+ - #address-cells: Must be set to 2 to allow memory address translation
+ - #size-cells: Must be set to 1 to allow CS address passing
+ - ranges: Must be set up to reflect the memory layout with four
+ integer values for each chip-select line in use:
+
+ <cs-number> 0 <physical address of mapping> <size>
+
+Optional properties:
+
+ - fsl,weim-cs-gpr: For "fsl,imx50-weim" and "fsl,imx6q-weim" type of
+ devices, it should be the phandle to the system General
+ Purpose Register controller that contains WEIM CS GPR
+ register, e.g. IOMUXC_GPR1 on i.MX6Q. IOMUXC_GPR1[11:0]
+ should be set up as one of the following 4 possible
+ values depending on the CS space configuration.
+
+ IOMUXC_GPR1[11:0] CS0 CS1 CS2 CS3
+ ---------------------------------------------
+ 05 128M 0M 0M 0M
+ 033 64M 64M 0M 0M
+ 0113 64M 32M 32M 0M
+ 01111 32M 32M 32M 32M
+
+ In case that the property is absent, the reset value or
+ what bootloader sets up in IOMUXC_GPR1[11:0] will be
+ used.
+
+ - fsl,burst-clk-enable For "fsl,imx50-weim" and "fsl,imx6q-weim" type of
+ devices, the presence of this property indicates that
+ the weim bus should operate in Burst Clock Mode.
+
+Timing property for child nodes. It is mandatory, not optional.
+
+ - fsl,weim-cs-timing: The timing array, contains timing values for the
+ child node. We get the CS indexes from the address
+ ranges in the child node's "reg" property.
+ The number of registers depends on the selected chip:
+ For i.MX1, i.MX21 ("fsl,imx1-weim") there are two
+ registers: CSxU, CSxL.
+ For i.MX25, i.MX27, i.MX31 and i.MX35 ("fsl,imx27-weim")
+ there are three registers: CSCRxU, CSCRxL, CSCRxA.
+ For i.MX50, i.MX53 ("fsl,imx50-weim"),
+ i.MX51 ("fsl,imx51-weim") and i.MX6Q ("fsl,imx6q-weim")
+ there are six registers: CSxGCR1, CSxGCR2, CSxRCR1,
+ CSxRCR2, CSxWCR1, CSxWCR2.
+
+Example for an imx6q-sabreauto board, the NOR flash connected to the WEIM:
+
+ weim: weim@21b8000 {
+ compatible = "fsl,imx6q-weim";
+ reg = <0x021b8000 0x4000>;
+ clocks = <&clks 196>;
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges = <0 0 0x08000000 0x08000000>;
+ fsl,weim-cs-gpr = <&gpr>;
+
+ nor@0,0 {
+ compatible = "cfi-flash";
+ reg = <0 0 0x02000000>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ bank-width = <2>;
+ fsl,weim-cs-timing = <0x00620081 0x00000001 0x1c022000
+ 0x0000c000 0x1404a38e 0x00000000>;
+ };
+ };
+
+Example for an imx6q-based board, a multi-chipselect device connected to WEIM:
+
+In this case, both chip select 0 and 1 will be configured with the same timing
+array values.
+
+ weim: weim@21b8000 {
+ compatible = "fsl,imx6q-weim";
+ reg = <0x021b8000 0x4000>;
+ clocks = <&clks 196>;
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges = <0 0 0x08000000 0x02000000
+ 1 0 0x0a000000 0x02000000
+ 2 0 0x0c000000 0x02000000
+ 3 0 0x0e000000 0x02000000>;
+ fsl,weim-cs-gpr = <&gpr>;
+
+ acme@0 {
+ compatible = "acme,whatever";
+ reg = <0 0 0x100>, <0 0x400000 0x800>,
+ <1 0x400000 0x800>;
+ fsl,weim-cs-timing = <0x024400b1 0x00001010 0x20081100
+ 0x00000000 0xa0000240 0x00000000>;
+ };
+ };