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  1. 17 8月, 2014 3 次提交
    • X
      regmap: Add the DT binding documentation for endianness · 275876e2
      由 Xiubo Li 提交于 
      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: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
      275876e2
    • X
      regmap: add DT endianness binding support. · d647c199
      由 Xiubo Li 提交于 
      For many drivers which will support rich endianness of Devices
need define DT properties by itself with the binding support.

The endianness using regmap:
Index      Device     Properties if needs bytes-swap,
                      or just ignore it
-------------------------------------------------------------
1          BE         'big-endian'
2          LE         'little-endian'

The properties include all the register values and the buffers.
And these properties are very usful for the MMIO devices:

Such as: a memory-mapped device, on one SoC is in BE mode, while
in another SoC will be in LE mode, and the CPU will always in LE
mode.

For the first case, we must use cpu_to_be32/be32_to_cpu for
32-bit registers accessing, so the 'big-endian' property is needed.

For the second case, we can just ignore the bytes-swap
functions like cpu_to_le32/le32_to_cpu, so the 'little-endian'
property could be abscent.

And vice versa...
Signed-off-by: NXiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: NMark Brown <broonie@linaro.org>
      d647c199
    • L
      Linux 3.17-rc1 · 7d1311b9
      由 Linus Torvalds 提交于
      7d1311b9
  3. 16 8月, 2014 37 次提交