--- zzzz-none-000/linux-3.10.107/Documentation/devicetree/bindings/spi/spi-davinci.txt 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/Documentation/devicetree/bindings/spi/spi-davinci.txt 2021-02-04 17:41:59.000000000 +0000 @@ -1,5 +1,10 @@ Davinci SPI controller device bindings +Links on DM: +Keystone 2 - http://www.ti.com/lit/ug/sprugp2a/sprugp2a.pdf +dm644x - http://www.ti.com/lit/ug/sprue32a/sprue32a.pdf +OMAP-L138/da830 - http://www.ti.com/lit/ug/spruh77a/spruh77a.pdf + Required properties: - #address-cells: number of cells required to define a chip select address on the SPI bus. Should be set to 1. @@ -7,8 +12,11 @@ - compatible: - "ti,dm6441-spi" for SPI used similar to that on DM644x SoC family - "ti,da830-spi" for SPI used similar to that on DA8xx SoC family + - "ti,keystone-spi" for SPI used similar to that on Keystone2 SoC + family - reg: Offset and length of SPI controller register space -- num-cs: Number of chip selects +- num-cs: Number of chip selects. This includes internal as well as + GPIO chip selects. - ti,davinci-spi-intr-line: interrupt line used to connect the SPI IP to the interrupt controller within the SoC. Possible values are 0 and 1. Manual says one of the two possible interrupt @@ -17,6 +25,36 @@ - interrupts: interrupt number mapped to CPU. - clocks: spi clk phandle +Optional: +- cs-gpios: gpio chip selects + For example to have 3 internal CS and 2 GPIO CS, user could define + cs-gpios = <0>, <0>, <0>, <&gpio1 30 0>, <&gpio1 31 0>; + where first three are internal CS and last two are GPIO CS. + +Optional properties for slave devices: +SPI slave nodes can contain the following properties. +Not all SPI Peripherals from Texas Instruments support this. +Please check SPI peripheral documentation for a device before using these. + +- ti,spi-wdelay : delay between transmission of words + (SPIFMTn.WDELAY, SPIDAT1.WDEL) must be specified in number of SPI module + clock periods. + + delay = WDELAY * SPI_module_clock_period + 2 * SPI_module_clock_period + +Below is timing diagram which shows functional meaning of +"ti,spi-wdelay" parameter. + + +-+ +-+ +-+ +-+ +-+ +-+ +-+ +-+ +SPI_CLK | | | | | | | | | | | | | | | | + +----------+ +-+ +-+ +-+ +-+ +---------------------------+ +-+ +-+ +- + +SPI_SOMI/SIMO+-----------------+ +----------- + +----------+ word1 +---------------------------+word2 + +-----------------+ +----------- + WDELAY + <--------------------------> + Example of a NOR flash slave device (n25q032) connected to DaVinci SPI controller device over the SPI bus. @@ -36,6 +74,7 @@ compatible = "st,m25p32"; spi-max-frequency = <25000000>; reg = <0>; + ti,spi-wdelay = <8>; partition@0 { label = "u-boot-spl";