Re: [PATCH 2/3] dt-bindings: rtc: update stm32-rtc documentation for stm32mp1 rtc

[Rob Herring <robh@kernel.org>]

On Thu, Apr 19, 2018 at 03:34:04PM +0200, Amelie Delaunay wrote:
> RTC embedded in stm32mp1 SoC is slightly different from stm32h7 one, it
> doesn't require to disable backup domain write protection, and rtc_ck
> parent clock assignment isn't allowed.
> To sum up, stm32mp1 RTC requires 2 clocks, pclk and rtc_ck, and an RTC
> alarm interrupt.
> 
> Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
> ---
>  .../devicetree/bindings/rtc/st,stm32-rtc.txt       | 27 +++++++++++++++++-----
>  1 file changed, 21 insertions(+), 6 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> index 00f8b5d..f1c2080 100644
> --- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> +++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.txt
> @@ -1,25 +1,31 @@
>  STM32 Real Time Clock
>  
>  Required properties:
> -- compatible: can be either "st,stm32-rtc" or "st,stm32h7-rtc", depending on
> -  the device is compatible with stm32(f4/f7) or stm32h7.
> +- compatible: can be "st,stm32-rtc", "st,stm32h7-rtc" or "st,stm32mp1-rtc",
> +	      depending on the device is compatible with stm32(f4/f7), stm32h7
> +	      or stm32mp1.

One compatible per line please.

>  - reg: address range of rtc register set.
>  - clocks: can use up to two clocks, depending on part used:
>    - "rtc_ck": RTC clock source.
> -    It is required on stm32(f4/f7) and stm32h7.
> +    It is required on stm32(f4/f7/h7/mp1).

IOW, required for all?

>    - "pclk": RTC APB interface clock.
>      It is not present on stm32(f4/f7).
> -    It is required on stm32h7.
> +    It is required on stm32(h7/mp1).
>  - clock-names: must be "rtc_ck" and "pclk".
> -    It is required only on stm32h7.
> +    It is required on stm32(h7/mp1).
>  - interrupt-parent: phandle for the interrupt controller.
> +    It is required on stm32(f4/f7/h7).
>  - interrupts: rtc alarm interrupt.
> +- interrupts-extended: replace interrupts property on stm32mp1, to specify rtc
> +  alarm wakeup interrupt, which is on exti interrupt controller instead of gic.
> +    It is required on stm32mp1.

Just document 'interrupts'. interrupts-extended is implicitly supported 
and what the interrupts are connected to is outside the scope of this 
binding.

>  - st,syscfg: phandle/offset/mask triplet. The phandle to pwrcfg used to
>    access control register at offset, and change the dbp (Disable Backup
>    Protection) bit represented by the mask, mandatory to disable/enable backup
>    domain (RTC registers) write protection.
> +    It is required on stm32(f4/f7/h7).
>  
> -Optional properties (to override default rtc_ck parent clock):
> +Optional properties (to override default rtc_ck parent clock on stm32(f4/f7/h7):
>  - assigned-clocks: reference to the rtc_ck clock entry.
>  - assigned-clock-parents: phandle of the new parent clock of rtc_ck.
>  
> @@ -48,3 +54,12 @@ Example:
>  		interrupt-names = "alarm";
>  		st,syscfg = <&pwrcfg 0x00 0x100>;
>  	};
> +
> +	rtc: rtc@5c004000 {
> +		compatible = "st,stm32mp1-rtc";
> +		reg = <0x5c004000 0x400>;
> +		clocks = <&rcc RTCAPB>, <&rcc RTC>;
> +		clock-names = "pclk", "rtc_ck";
> +		interrupts-extended = <&intc GIC_SPI 3 IRQ_TYPE_NONE>,
> +				      <&exti 19 1>;
> +	};
> -- 
> 2.7.4
>