diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/devicetree/bindings/spi/spi-davinci.txt | 30 | ||||
-rw-r--r-- | Documentation/spi/spi-summary | 6 |
2 files changed, 33 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/spi/spi-davinci.txt b/Documentation/devicetree/bindings/spi/spi-davinci.txt index f80887bca0d6..12ecfe9e3599 100644 --- a/Documentation/devicetree/bindings/spi/spi-davinci.txt +++ b/Documentation/devicetree/bindings/spi/spi-davinci.txt @@ -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. @@ -24,6 +29,30 @@ Optional: 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. @@ -43,6 +72,7 @@ spi0:spi@20BF0000 { compatible = "st,m25p32"; spi-max-frequency = <25000000>; reg = <0>; + ti,spi-wdelay = <8>; partition@0 { label = "u-boot-spl"; diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary index 7982bcc4d151..d29734bff28c 100644 --- a/Documentation/spi/spi-summary +++ b/Documentation/spi/spi-summary @@ -601,13 +601,13 @@ THANKS TO Contributors to Linux-SPI discussions include (in alphabetical order, by last name): +Mark Brown David Brownell Russell King +Grant Likely Dmitry Pervushin Stephen Street Mark Underwood Andrew Victor -Vitaly Wool -Grant Likely -Mark Brown Linus Walleij +Vitaly Wool |