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linux/Documentation/devicetree/bindings/regmap/regmap.txt

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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 <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2014-07-15 12:23:03 +08:00
Device-Tree binding for regmap
The endianness mode of CPU & Device scenarios:
Index Device Endianness properties
---------------------------------------------------
1 BE 'big-endian'
2 LE 'little-endian'
regmap: Add explict native endian flag to DT bindings Currently the binding document says that if no endianness is configured we use native endian but this is not in fact true for all binding types and we do have some devices that really want native endianness such as Broadcom MIPS SoCs where switching the endianness of the CPU also switches the endianness of external IPs. Provide an explicit option for this. Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-27 01:59:30 +08:00
3 Native 'native-endian'
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 <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2014-07-15 12:23:03 +08:00
For one device driver, which will run in different scenarios above
on different SoCs using the devicetree, we need one way to simplify
this.
regmap: Add explict native endian flag to DT bindings Currently the binding document says that if no endianness is configured we use native endian but this is not in fact true for all binding types and we do have some devices that really want native endianness such as Broadcom MIPS SoCs where switching the endianness of the CPU also switches the endianness of external IPs. Provide an explicit option for this. Signed-off-by: Mark Brown <broonie@kernel.org>
2016-01-27 01:59:30 +08:00
Optional properties:
- {big,little,native}-endian: these are boolean properties, if absent
then the implementation will choose a default based on the device
being controlled. These properties are for register values and all
the buffers only. Native endian means that the CPU and device have
the same endianness.
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 <Li.Xiubo@freescale.com> Signed-off-by: Mark Brown <broonie@linaro.org>
2014-07-15 12:23:03 +08:00
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;
};