From mboxrd@z Thu Jan 1 00:00:00 1970 From: cw00.choi@samsung.com (Chanwoo Choi) Date: Fri, 24 Oct 2014 19:34:54 +0900 Subject: [PATCH 3/5] clk: samsung: Document binding for Exynos4415 clock controller In-Reply-To: <544A2AA5.3020407@samsung.com> References: <1413775749-17539-1-git-send-email-cw00.choi@samsung.com> <1413775935-17743-3-git-send-email-cw00.choi@samsung.com> <544A2AA5.3020407@samsung.com> Message-ID: <544A2B4E.8090604@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Sylwester, On 10/24/2014 07:32 PM, Sylwester Nawrocki wrote: > On 20/10/14 05:32, Chanwoo Choi wrote: >> The Exynos4415 clocks are statically listed and registered using the >> Samsung specific common clock helper functions. Both device tree based >> clock lookup and clkdev based clock lookups are supported. > > I think the above text is not relevant, DT binding is not supposed > to depend on any OS. Instead I would just put here something like: > > "This patch adds DT binding documentation for Exynos4415 SoC system > clock controllers." OK, I will modify it as your comment. > >> Cc: Sylwester Nawrocki >> Cc: Tomasz Figa >> Signed-off-by: Chanwoo Choi >> Acked-by: Kyungmin Park >> --- >> .../devicetree/bindings/clock/exynos4415-clock.txt | 49 ++++++++++++++++++++++ >> 1 file changed, 49 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/clock/exynos4415-clock.txt >> >> diff --git a/Documentation/devicetree/bindings/clock/exynos4415-clock.txt b/Documentation/devicetree/bindings/clock/exynos4415-clock.txt >> new file mode 100644 >> index 0000000..8aa4f4f >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/clock/exynos4415-clock.txt >> @@ -0,0 +1,49 @@ >> +* Samsung Exynos4415 Clock Controller >> + >> +The Exynos4415 clock controller generates and supplies clock to various >> +controllers within the Exynos4415 SoC. > > s/controllers/consumer devices/ ? > >> + >> +Required Properties: > > s/P/p/ ? I'll fix it. > >> + >> +- compatible: should be one of the following. > > s/./:/ ? I will change it (. -> :) > >> + - "samsung,exynos4415-cmu" - controller compatible with Exynos4415 SoC. > >>>From current description it seems "samsung,exynos4415-cmu-dmc" is compatible > with "samsung,exynos4415-cmu", which is not the case AFAIK. > Perhaps we should change description here to something along the lines of: > > - "samsung,exynos4415-cmu" - for the main system clocks controller > (CMU_LEFTBUS, CMU_RIGHTBUS, CMU_TOP, CMU_CPU clock domains), > >> + - "samsung,exynos4415-cmu-dmc" - controller compatible with >> + Exynos4415 SoC for Dynamic Memory Controller domain. > > This seems unclear, how about > > - "samsung,exynos4415-cmu-dmc" - for the Exynos4415 SoC DRAM Memory > Controller (DMC) domain clock controller. > > ? OK, I'll modify it >> +- reg: physical base address of the controller and length of memory mapped >> + region. >> + >> +- #clock-cells: should be 1. >> + >> +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 >> +dt-bindings/clock/exynos4415.h header and can be used in device >> +tree sources. > >> +Example 1: An example of a clock controller node is listed below. >> + >> + cmu: clock-controller at 10030000 { >> + compatible = "samsung,exynos4415-cmu"; >> + reg = <0x10030000 0x18000>; >> + #clock-cells = <1>; >> + }; >> + >> + cmu-dmc: clock-controller at 105C0000 { >> + compatible = "samsung,exynos4415-cmu-dmc"; >> + reg = <0x105C0000 0x3000>; >> + #clock-cells = <1>; >> + }; >> + >> +Example 2: UART controller node that consumes the clock generated by the clock >> + controller. Refer to the standard clock bindings for information >> + about 'clocks' and 'clock-names' property. >> + >> + serial_0: serial at 13800000 { >> + compatible = "samsung,exynos4210-uart"; >> + reg = <0x13800000 0x100>; >> + interrupts = <0 109 0>; >> + clocks = <&cmu CLK_UART0>, <&cmu CLK_SCLK_UART0>; >> + clock-names = "uart", "clk_uart_baud0"; >> + }; > > I think we could omit those example snippets, it's all generic stuff and > there is already plenty examples in descriptions of the DT binding for > other SoCs. OK, I'll drop this example. Thanks for your review. Best Regards, Chanwoo Choi > > -- > Regards, > Sylwester >