Re: [PATCH v4 02/20] PM / devfreq: exynos: Add documentation for generic exynos bus frequency driver

[MyungJoo Ham <myungjoo.ham@samsung.com>]

>   
>  This patch adds the documentation for generic exynos bus frequency
> driver.
> 
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

A little changes following:

> ---
>  .../devicetree/bindings/devfreq/exynos-bus.txt     | 93 ++++++++++++++++++++++
>  1 file changed, 93 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> 
> diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> new file mode 100644
> index 000000000000..e32daef328da
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt
> @@ -0,0 +1,93 @@
> +* Generic Exynos Bus frequency device
> +
> +The Samsung Exynos SoC have many buses for data transfer between DRAM

+The Samsung Exynos SoC has many buses for data transfer between DRAM

or

+The Samsung Exynos SoCs have many buses for data transfer between DRAM
(because you intend to support mulitple Exynos SoCs)

> +and sub-blocks in SoC. Almost Exynos SoC have the common architecture

+and sub-blocks in SoC. Most Exynos SoCs share the common architecture

> +for buses. Generally, the each bus of Exynos SoC includes the source clock

+for buses. Generally, each bus of Exynos SoC includes a source clock

> +and power line and then is able to change the clock according to the usage

+and a power line, which are able to change the clock frequency 

> +of each buses on runtime. When gathering the usage of each buses on runtime,

+of the bus in runtime. To monitor the usage of each bus in runtime,

> +the driver uses the PPMU (Platform Performance Monitoring Unit) which

+the driver uses the PPMU (Platform Performance Monitoring Unit), which

> +is able to measure the current load of sub-blocks.
> +
> +There are a little different composition among Exynos SoC because each Exynos
> +SoC has the different sub-blocks. So, this difference should be specified

+SoC has different sub-blocks. Therefore, such difference should be specified

> +in devicetree file instead of each device driver. In result, this driver
> +is able to support the bus frequency for all Exynos SoCs.
> +
[]