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+* Samsung SPI Controller
+
+The Samsung SPI controller is used to interface with various devices such as flash
+and display controllers using the SPI communication interface.
+
+Required SoC Specific Properties:
+
+- compatible: should be one of the following.
+ - samsung,s3c2443-spi: for s3c2443, s3c2416 and s3c2450 platforms
+ - samsung,s3c6410-spi: for s3c6410 platforms
+ - samsung,s5p6440-spi: for s5p6440 and s5p6450 platforms
+ - samsung,s5pv210-spi: for s5pv210 and s5pc110 platforms
+ - samsung,exynos4210-spi: for exynos4 and exynos5 platforms
+
+- reg: physical base address of the controller and length of memory mapped
+ region.
+
+- interrupts: The interrupt number to the cpu. The interrupt specifier format
+ depends on the interrupt controller.
+
+[PRELIMINARY: the dma channel allocation will change once there are
+official DMA bindings]
+
+- tx-dma-channel: The dma channel specifier for tx operations. The format of
+ the dma specifier depends on the dma controller.
+
+- rx-dma-channel: The dma channel specifier for rx operations. The format of
+ the dma specifier depends on the dma controller.
+
+Required Board Specific Properties:
+
+- #address-cells: should be 1.
+- #size-cells: should be 0.
+- gpios: The gpio specifier for clock, mosi and miso interface lines (in the
+ order specified). The format of the gpio specifier depends on the gpio
+ controller.
+
+Optional Board Specific Properties:
+
+- samsung,spi-src-clk: If the spi controller includes a internal clock mux to
+ select the clock source for the spi bus clock, this property can be used to
+ indicate the clock to be used for driving the spi bus clock. If not specified,
+ the clock number 0 is used as default.
+
+- num-cs: Specifies the number of chip select lines supported. If
+ not specified, the default number of chip select lines is set to 1.
+
+SPI Controller specific data in SPI slave nodes:
+
+- The spi slave nodes should provide the following information which is required
+ by the spi controller.
+
+ - cs-gpio: A gpio specifier that specifies the gpio line used as
+ the slave select line by the spi controller. The format of the gpio
+ specifier depends on the gpio controller.
+
+ - samsung,spi-feedback-delay: The sampling phase shift to be applied on the
+ miso line (to account for any lag in the miso line). The following are the
+ valid values.
+
+ - 0: No phase shift.
+ - 1: 90 degree phase shift sampling.
+ - 2: 180 degree phase shift sampling.
+ - 3: 270 degree phase shift sampling.
+
+Aliases:
+
+- All the SPI controller nodes should be represented in the aliases node using
+ the following format 'spi{n}' where n is a unique number for the alias.
+
+
+Example:
+
+- SoC Specific Portion:
+
+ spi_0: spi@12d20000 {
+ compatible = "samsung,exynos4210-spi";
+ reg = <0x12d20000 0x100>;
+ interrupts = <0 66 0>;
+ tx-dma-channel = <&pdma0 5>;
+ rx-dma-channel = <&pdma0 4>;
+ };
+
+- Board Specific Portion:
+
+ spi_0: spi@12d20000 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ gpios = <&gpa2 4 2 3 0>,
+ <&gpa2 6 2 3 0>,
+ <&gpa2 7 2 3 0>;
+
+ w25q80bw@0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "w25x80";
+ reg = <0>;
+ spi-max-frequency = <10000>;
+
+ controller-data {
+ cs-gpio = <&gpa2 5 1 0 3>;
+ samsung,spi-feedback-delay = <0>;
+ };
+
+ partition@0 {
+ label = "U-Boot";
+ reg = <0x0 0x40000>;
+ read-only;
+ };
+
+ partition@40000 {
+ label = "Kernel";
+ reg = <0x40000 0xc0000>;
+ };
+ };
+ };
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