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Diffstat (limited to 'Documentation/devicetree')
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-stp-xway.txt | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-stp-xway.txt b/Documentation/devicetree/bindings/gpio/gpio-stp-xway.txt new file mode 100644 index 0000000..854de13 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-stp-xway.txt @@ -0,0 +1,42 @@ +Lantiq SoC Serial To Parallel (STP) GPIO controller + +The Serial To Parallel (STP) is found on MIPS based Lantiq socs. It is a +peripheral controller used to drive external shift register cascades. At most +3 groups of 8 bits can be driven. The hardware is able to allow the DSL modem +to drive the 2 LSBs of the cascade automatically. + + +Required properties: +- compatible : Should be "lantiq,gpio-stp-xway" +- reg : Address and length of the register set for the device +- #gpio-cells : Should be two. The first cell is the pin number and + the second cell is used to specify optional parameters (currently + unused). +- gpio-controller : Marks the device node as a gpio controller. + +Optional properties: +- lantiq,shadow : The default value that we shall assume as already set on the + shift register cascade. +- lantiq,groups : Set the 3 bit mask to select which of the 3 groups are enabled + in the shift register cascade. +- lantiq,dsl : The dsl core can control the 2 LSBs of the gpio cascade. This 2 bit + property can enable this feature. +- lantiq,phy1 : The gphy1 core can control 3 bits of the gpio cascade. +- lantiq,phy2 : The gphy2 core can control 3 bits of the gpio cascade. +- lantiq,rising : use rising instead of falling edge for the shift register + +Example: + +gpio1: stp@E100BB0 { + compatible = "lantiq,gpio-stp-xway"; + reg = <0xE100BB0 0x40>; + #gpio-cells = <2>; + gpio-controller; + + lantiq,shadow = <0xffff>; + lantiq,groups = <0x7>; + lantiq,dsl = <0x3>; + lantiq,phy1 = <0x7>; + lantiq,phy2 = <0x7>; + /* lantiq,rising; */ +}; |