Re: [PATCH 1/2] dt-bindings: rtc: add battery-low-hw-alarm property

[Rob Herring <robh@kernel.org>]

On Wed, Apr 03, 2019 at 04:52:44PM +0200, Flavio Suligoi wrote:
> Some RTC devices have a battery-low automatic detection circuit.
> The battery-low event is usually reported with:
> 
> - a bit change in a RTC status register
> - a hw signaling (generally using an interrupt generation), changing
>   the hw level of a specific pin;
> 
> The new property "battery-low-hw-alarm" enable the RTC to generate the
> hw signaling in case of battery-low event.
> 
> Signed-off-by: Flavio Suligoi <f.suligoi@asem.it>
> ---
>  Documentation/devicetree/bindings/rtc/rtc.txt | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/rtc/rtc.txt b/Documentation/devicetree/bindings/rtc/rtc.txt
> index a97fc6a..f93a44d 100644
> --- a/Documentation/devicetree/bindings/rtc/rtc.txt
> +++ b/Documentation/devicetree/bindings/rtc/rtc.txt
> @@ -31,6 +31,9 @@ below.
>                              expressed in femto Farad (fF).
>                              The default value shall be listed (if optional),
>                              and likewise all valid values.
> +- battery-low-hw-alarm :    Enable the "battery-low" output pin. This function
> +                            is available on the following devices:
> +                            - pcf2127 - pin used for alarm: INTn

Boolean? If there's cases where which pin is selectable, then we'd need 
this to take a value. Not sure how likely that is?

Rob