| The soft SPI bus implementation allows the use of GPIO pins to simulate a |
| SPI bus. No SPI host is required for this to work. The down-side is that the |
| performance will typically be much lower than a real SPI bus. |
| The soft SPI node requires the following properties: |
| compatible: "u-boot,soft-spi" |
| soft_spi_cs: GPIO number to use for SPI chip select (output) |
| soft_spi_sclk: GPIO number to use for SPI clock (output) |
| soft_spi_mosi: GPIO number to use for SPI MOSI line (output) |
| soft_spi_miso GPIO number to use for SPI MISO line (input) |
| spi-delay-us: Number of microseconds of delay between each CS transition |
| The GPIOs should be specified as required by the GPIO controller referenced. |
| The first cell holds the phandle of the controller and the second cell |
| typically holds the GPIO number. |
| compatible = "u-boot,soft-spi"; |
| cs-gpio = <&gpio 235 0>; /* Y43 */ |
| sclk-gpio = <&gpio 225 0>; /* Y31 */ |
| mosi-gpio = <&gpio 227 0>; /* Y33 */ |
| miso-gpio = <&gpio 224 0>; /* Y30 */ |