diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio/spear_spics.txt')
-rw-r--r-- | Documentation/devicetree/bindings/gpio/spear_spics.txt | 49 |
1 files changed, 0 insertions, 49 deletions
diff --git a/Documentation/devicetree/bindings/gpio/spear_spics.txt b/Documentation/devicetree/bindings/gpio/spear_spics.txt deleted file mode 100644 index dd04d96e6ff1..000000000000 --- a/Documentation/devicetree/bindings/gpio/spear_spics.txt +++ /dev/null @@ -1,49 +0,0 @@ -=== ST Microelectronics SPEAr SPI CS Driver === - -SPEAr platform provides a provision to control chipselects of ARM PL022 Prime -Cell spi controller through its system registers, which otherwise remains under -PL022 control. If chipselect remain under PL022 control then they would be -released as soon as transfer is over and TxFIFO becomes empty. This is not -desired by some of the device protocols above spi which expect (multiple) -transfers without releasing their chipselects. - -Chipselects can be controlled by software by turning them as GPIOs. SPEAr -provides another interface through system registers through which software can -directly control each PL022 chipselect. Hence, it is natural for SPEAr to export -the control of this interface as gpio. - -Required properties: - - * compatible: should be defined as "st,spear-spics-gpio" - * reg: mentioning address range of spics controller - * st-spics,peripcfg-reg: peripheral configuration register offset - * st-spics,sw-enable-bit: bit offset to enable sw control - * st-spics,cs-value-bit: bit offset to drive chipselect low or high - * st-spics,cs-enable-mask: chip select number bit mask - * st-spics,cs-enable-shift: chip select number program offset - * gpio-controller: Marks the device node as gpio controller - * #gpio-cells: should be 1 and will mention chip select number - -All the above bit offsets are within peripcfg register. - -Example: -------- -spics: spics@e0700000{ - compatible = "st,spear-spics-gpio"; - reg = <0xe0700000 0x1000>; - st-spics,peripcfg-reg = <0x3b0>; - st-spics,sw-enable-bit = <12>; - st-spics,cs-value-bit = <11>; - st-spics,cs-enable-mask = <3>; - st-spics,cs-enable-shift = <8>; - gpio-controller; - #gpio-cells = <2>; -}; - - -spi0: spi@e0100000 { - num-cs = <3>; - cs-gpios = <&gpio1 7 0>, <&spics 0>, - <&spics 1>; - ... -} |