From 275876e208e28abf4b96ec89030e482b1331ee75 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Tue, 15 Jul 2014 12:23:03 +0800 Subject: regmap: Add the DT binding documentation for endianness Device-Tree binding for device endianness Index Device Endianness properties --------------------------------------------------- 1 BE 'big-endian' 2 LE 'little-endian' For one device driver, which will run in different scenarios above on different SoCs using the devicetree, we need one way to simplify this. Signed-off-by: Xiubo Li Signed-off-by: Mark Brown diff --git a/Documentation/devicetree/bindings/regmap/regmap.txt b/Documentation/devicetree/bindings/regmap/regmap.txt new file mode 100644 index 0000000..b494f8b --- /dev/null +++ b/Documentation/devicetree/bindings/regmap/regmap.txt @@ -0,0 +1,47 @@ +Device-Tree binding for regmap + +The endianness mode of CPU & Device scenarios: +Index Device Endianness properties +--------------------------------------------------- +1 BE 'big-endian' +2 LE 'little-endian' + +For one device driver, which will run in different scenarios above +on different SoCs using the devicetree, we need one way to simplify +this. + +Required properties: +- {big,little}-endian: these are boolean properties, if absent + meaning that the CPU and the Device are in the same endianness mode, + these properties are for register values and all the buffers only. + +Examples: +Scenario 1 : CPU in LE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... +}; + +Scenario 2 : CPU in LE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + big-endian; +}; + +Scenario 3 : CPU in BE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... +}; + +Scenario 4 : CPU in BE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + little-endian; +}; -- cgit v0.10.2