LXR linux/Documentation/devicetree/bindings/spi/spi-samsung.txt

   1* Samsung SPI Controller
   2
   3The Samsung SPI controller is used to interface with various devices such as flash
   4and display controllers using the SPI communication interface.
   5
   6Required SoC Specific Properties:
   7
   8- compatible: should be one of the following.
   9    - samsung,s3c2443-spi: for s3c2443, s3c2416 and s3c2450 platforms
  10    - samsung,s3c6410-spi: for s3c6410 platforms
  11    - samsung,s5p6440-spi: for s5p6440 and s5p6450 platforms
  12    - samsung,s5pv210-spi: for s5pv210 and s5pc110 platforms
  13    - samsung,exynos4210-spi: for exynos4 and exynos5 platforms
  14
  15- reg: physical base address of the controller and length of memory mapped
  16  region.
  17
  18- interrupts: The interrupt number to the cpu. The interrupt specifier format
  19  depends on the interrupt controller.
  20
  21[PRELIMINARY: the dma channel allocation will change once there are
  22official DMA bindings]
  23
  24- tx-dma-channel: The dma channel specifier for tx operations. The format of
  25  the dma specifier depends on the dma controller.
  26
  27- rx-dma-channel: The dma channel specifier for rx operations. The format of
  28  the dma specifier depends on the dma controller.
  29
  30Required Board Specific Properties:
  31
  32- #address-cells: should be 1.
  33- #size-cells: should be 0.
  34
  35Optional Board Specific Properties:
  36
  37- samsung,spi-src-clk: If the spi controller includes a internal clock mux to
  38  select the clock source for the spi bus clock, this property can be used to
  39  indicate the clock to be used for driving the spi bus clock. If not specified,
  40  the clock number 0 is used as default.
  41
  42- num-cs: Specifies the number of chip select lines supported. If
  43  not specified, the default number of chip select lines is set to 1.
  44
  45SPI Controller specific data in SPI slave nodes:
  46
  47- The spi slave nodes should provide the following information which is required
  48  by the spi controller.
  49
  50  - cs-gpio: A gpio specifier that specifies the gpio line used as
  51    the slave select line by the spi controller. The format of the gpio
  52    specifier depends on the gpio controller.
  53
  54  - samsung,spi-feedback-delay: The sampling phase shift to be applied on the
  55    miso line (to account for any lag in the miso line). The following are the
  56    valid values.
  57
  58      - 0: No phase shift.
  59      - 1: 90 degree phase shift sampling.
  60      - 2: 180 degree phase shift sampling.
  61      - 3: 270 degree phase shift sampling.
  62
  63Aliases:
  64
  65- All the SPI controller nodes should be represented in the aliases node using
  66  the following format 'spi{n}' where n is a unique number for the alias.
  67
  68
  69Example:
  70
  71- SoC Specific Portion:
  72
  73        spi_0: spi@12d20000 {
  74                compatible = "samsung,exynos4210-spi";
  75                reg = <0x12d20000 0x100>;
  76                interrupts = <0 66 0>;
  77                tx-dma-channel = <&pdma0 5>;
  78                rx-dma-channel = <&pdma0 4>;
  79        };
  80
  81- Board Specific Portion:
  82
  83        spi_0: spi@12d20000 {
  84                #address-cells = <1>;
  85                #size-cells = <0>;
  86                pinctrl-names = "default";
  87                pinctrl-0 = <&spi0_bus>;
  88
  89                w25q80bw@0 {
  90                        #address-cells = <1>;
  91                        #size-cells = <1>;
  92                        compatible = "w25x80";
  93                        reg = <0>;
  94                        spi-max-frequency = <10000>;
  95
  96                        controller-data {
  97                                cs-gpio = <&gpa2 5 1 0 3>;
  98                                samsung,spi-feedback-delay = <0>;
  99                        };
 100
 101                        partition@0 {
 102                                label = "U-Boot";
 103                                reg = <0x0 0x40000>;
 104                                read-only;
 105                        };
 106
 107                        partition@40000 {
 108                                label = "Kernel";
 109                                reg = <0x40000 0xc0000>;
 110                        };
 111                };
 112        };
 113