[PATCH v2 5/9] dt-bindings: add documentation of rk3036 clock controller

[heiko@sntech.de (Heiko Stübner)]

Am Donnerstag, 17. September 2015, 18:32:49 schrieb Xing Zheng:
> Add the devicetree binding for the cru on the rk3036 which quite similar
> structured as previous clock controllers.
> 
> Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
> ---
> 
> Changes in v2: None
> 
>  .../bindings/clock/rockchip,rk3036-cru.txt         |   60
> ++++++++++++++++++++ 1 file changed, 60 insertions(+)
>  create mode 100644
> Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt
> 
> diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt
> b/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt new file
> mode 100644
> index 0000000..ac3037a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt
> @@ -0,0 +1,60 @@
> +* Rockchip RK3036 Clock and Reset Unit
> +
> +The RK3036 clock controller generates and supplies clock to various
> +controllers within the SoC and also implements a reset controller for SoC
> +peripherals.
> +
> +Required Properties:
> +
> +- compatible: should be "rockchip,rk3036-cru"
> +- reg: physical base address of the controller and length of memory mapped
> +  region.
> +- #clock-cells: should be 1.
> +- #reset-cells: should be 1.
> +
> +Optional Properties:
> +
> +- rockchip,grf: phandle to the syscon managing the "general register files"
> +  If missing pll rates are not changable, due to the missing pll lock
> status. +
> +Each clock is assigned an identifier and client nodes can use this
> identifier +to specify the clock which they consume. All available clocks
> are defined as +preprocessor macros in the dt-bindings/clock/rk3036-cru.h
> headers and can be +used in device tree sources. Similar macros exist for
> the reset sources in +these files.
> +
> +External clocks:
> +
> +There are several clocks that are generated outside the SoC. It is expected
> +that they are defined using standard clock bindings with following
> +clock-output-names:
> + - "xin24m" - crystal input - required,
> + - "xin32k" - rtc clock - optional,

The rk3036 does not seem to use a rtc clock, so this should probably go away

> + - "ext_i2s" - external I2S clock - optional,

> + - "ext_hsadc" - external HSADC clock - optional,
> + - "ext_vip" - external VIP clock - optional,
> + - "ext_isp" - external ISP clock - optional,
> + - "ext_jtag" - external JTAG clock - optional
There do not seem to exist external clock sources for hsadc, vip, isp and jtag 
in your clock tree?

missing here:
- ext_gmac

> +
> +Example: Clock controller node:
> +
> +	cru: cru at 20000000 {
> +		compatible = "rockchip,rk3036-cru";
> +		reg = <0x20000000 0x1000>;
> +		rockchip,grf = <&grf>;
> +
> +		#clock-cells = <1>;
> +		#reset-cells = <1>;
> +	};
> +
> +Example: UART controller node that consumes the clock generated by the
> clock +  controller:
> +
> +	uart0: serial at 20060000 {
> +		compatible = "snps,dw-apb-uart";
> +		reg = <0x20060000 0x100>;
> +		interrupts = <GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>;
> +		reg-shift = <2>;
> +		reg-io-width = <4>;
> +		clocks = <&cru SCLK_UART0>;
> +	};