Re: [PATCH 4/4] Documentation: atmel-at91: add DT bindings for fast startup

[Rob Herring]

On Thu, Jan 28, 2016 at 06:19:16PM +0800, Wenyou Yang wrote:
> Add DT bindings to configurate the PMC_FSMR and PMC_FSPR registers
> to trigger a fast restart signal to PMC.
> 
> Signed-off-by: Wenyou Yang <wenyou.yang@xxxxxxxxx>
> ---
> 
>  .../devicetree/bindings/arm/atmel-pmc.txt          |   74 ++++++++++++++++++++
>  1 file changed, 74 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/atmel-pmc.txt b/Documentation/devicetree/bindings/arm/atmel-pmc.txt
> index 795cc78..8d45ff9f 100644
> --- a/Documentation/devicetree/bindings/arm/atmel-pmc.txt
> +++ b/Documentation/devicetree/bindings/arm/atmel-pmc.txt
> @@ -12,3 +12,77 @@ Examples:
>  		compatible = "atmel,at91rm9200-pmc";
>  		reg = <0xfffffc00 0x100>;
>  	};
> +
> +PMC Fast Startup Signals
> +
> +The PMC Fast Start Signals are used as the wake up source to trigger the PMC
> +to wake up the system from the ULP1 mode.
> +
> +required properties:
> +- compatible: Should be "atmel,sama5d2-pmc-fast-startup".

Why the compatible? Does this correspond to some h/w block rather than 
features of the PMC? If it is simply because you want to have a separate 
driver, that is not a good reason.

> +
> +optional properties:
> +- atmel,fast-startup-wake-up: boolean to enable the WKUP pin to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-secumod: boolean to enable the Security Mode to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu0: boolean to enable the PIOBU0 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu1: boolean to enable the PIOBU1 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu2: boolean to enable the PIOBU2 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu3: boolean to enable the PIOBU3 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu4: boolean to enable the PIOBU4 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu5: boolean to enable the PIOBU5 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu6: boolean to enable the PIOBU6 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-piobu7: boolean to enable the PIOBU7 Input to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-gmac-wol: boolean to enable the GMAC Wake-up On LAN
> +  to trigger a fast restart signal to the PMC.
> +- atmel,fast-startup-rtc-alarm: boolean to enable the RTC Alarm to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-usb-resume: boolean to enable the USB Resume to trigger
> +  a fast restart signal to the PMC.
> +- atmel,fast-startup-sdmmc-cd: boolean to enable the SDMMC Card Detect
> +  to trigger a fast restart signal to the PMC.
> +- atmel,fast-startup-rxlp-match: boolean to enable the Backuo UART Receive
> +  Match Condition to trigger a fast restart signal to the PMC.
> +- atmel,fast-startup-acc-comparison: boolean to enable the Analog Comparator
> +  Controller (ACC) Comparison to to trigger a fast restart signal to the PMC.
> +
> +- atmel,fast-startup-wkup-pin-high: boolean to indicate if the WKUP Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.

Perhaps just make the above bool properties take a value to indicate 
high or low triggered.

> +- atmel,fast-startup-piobu0-high: boolean to indicate if the PIOBU0 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu1-high: boolean to indicate if the PIOBU1 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu2-high: boolean to indicate if the PIOBU2 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu3-high: boolean to indicate if the PIOBU3 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu4-high: boolean to indicate if the PIOBU4 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu5-high: boolean to indicate if the PIOBU5 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu6-high: boolean to indicate if the PIOBU6 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.
> +- atmel,fast-startup-piobu7-high: boolean to indicate if the PIOBU7 Pin is
> +  in the high level to trigger fast restart signal, otherwise low level.

This would be a long list in the DT if you set all these properties. 
Perhaps this should all be expressed in a more compact form.

> +
> +Example:
> +
> +	pmc: pmc@f0014000 {
> +		compatible = "atmel,sama5d2-pmc";
> +		reg = <0xf0014000 0x160>;
> +
> +		pmc_fast_restart {
> +			compatible = "atmel,sama5d2-pmc-fast-startup";
> +			atmel,fast-startup-wake-up;
> +			atmel,fast-startup-rtc-alarm;
> +		};
> +	};
> -- 
> 1.7.9.5
>