From 2be5263c5df45bbd5ad49ea8c394aca6e709d204 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 13 Jun 2018 21:28:38 +1000 Subject: dt-bindings: fsi: Document binding for the fsi-master-ast-cf "device" This isn't per-se a real device, it's a pseudo-device that represents the use of the Aspeed built-in ColdFire to implement the FSI protocol by bitbanging the GPIOs instead of doing it from the ARM core. Thus it's a drop-in replacement for the existing fsi-master-gpio pseudo-device for use on systems based on the Aspeed chips. It has most of the same properties, plus some more needed to operate the coprocessor. Signed-off-by: Benjamin Herrenschmidt Reviewed-by: Rob Herring --- .../devicetree/bindings/fsi/fsi-master-ast-cf.txt | 36 ++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt (limited to 'Documentation/devicetree/bindings/fsi') diff --git a/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt new file mode 100644 index 000000000000..3dc752db748b --- /dev/null +++ b/Documentation/devicetree/bindings/fsi/fsi-master-ast-cf.txt @@ -0,0 +1,36 @@ +Device-tree bindings for ColdFire offloaded gpio-based FSI master driver +------------------------------------------------------------------------ + +Required properties: + - compatible = + "aspeed,ast2400-cf-fsi-master" for an AST2400 based system + or + "aspeed,ast2500-cf-fsi-master" for an AST2500 based system + + - clock-gpios = ; : GPIO for FSI clock + - data-gpios = ; : GPIO for FSI data signal + - enable-gpios = ; : GPIO for enable signal + - trans-gpios = ; : GPIO for voltage translator enable + - mux-gpios = ; : GPIO for pin multiplexing with other + functions (eg, external FSI masters) + - memory-region = ; : Reference to the reserved memory for + the ColdFire. Must be 2M aligned on + AST2400 and 1M aligned on AST2500 + - aspeed,sram = ; : Reference to the SRAM node. + - aspeed,cvic = ; : Reference to the CVIC node. + +Examples: + + fsi-master { + compatible = "aspeed,ast2500-cf-fsi-master", "fsi-master"; + + clock-gpios = <&gpio 0>; + data-gpios = <&gpio 1>; + enable-gpios = <&gpio 2>; + trans-gpios = <&gpio 3>; + mux-gpios = <&gpio 4>; + + memory-region = <&coldfire_memory>; + aspeed,sram = <&sram>; + aspeed,cvic = <&cvic>; + } -- cgit v1.2.3