[1/3] dt-bindings: mfd: axp20x: Document backup battery charging property

This adds documentation for the "backup" property of the axp20x driver,
that controls the charging mechanism for the backup battery on axp20x.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>

On Sat, 30 Dec 2017, Paul Kocialkowski wrote:

> This adds documentation for the "backup" property of the axp20x driver,
> that controls the charging mechanism for the backup battery on axp20x.
> 
> Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> 
> diff --git a/Documentation/devicetree/bindings/mfd/axp20x.txt b/Documentation/devicetree/bindings/mfd/axp20x.txt
> index 9455503b0299..382776b29932 100644
> --- a/Documentation/devicetree/bindings/mfd/axp20x.txt
> +++ b/Documentation/devicetree/bindings/mfd/axp20x.txt
> @@ -58,6 +58,11 @@ Optional properties:
>  	      See Documentation/devicetree/bindings/regulator/regulator.txt
>  	      for more information on standard regulator bindings.
>  
> +- backup: An array of two integers for backup battery charging (axp20x-only),
> +	  describing the charging voltage in mV first and the charging current
> +	  in uA second. Backup battery charging is only enabled when these two
> +	  fields are filled.
> +
>  Optional properties for DCDC regulators:
>  - x-powers,dcdc-workmode: 1 for PWM mode, 0 for AUTO (PWM/PFM) mode
>  			  Default: Current hardware setting
> @@ -256,4 +261,6 @@ axp209: pmic@34 {
>  			/* unused but preferred to be managed by OS */
>  		};
>  	};
> +
> +	backup = <3000 200>;

It's unlikely that this will become a generic property, so you should
prefix it with your vendor ID.

>  };

Hi!

> This adds documentation for the "backup" property of the axp20x driver,
> that controls the charging mechanism for the backup battery on axp20x.
> 
> Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> 
> diff --git a/Documentation/devicetree/bindings/mfd/axp20x.txt b/Documentation/devicetree/bindings/mfd/axp20x.txt
> index 9455503b0299..382776b29932 100644
> --- a/Documentation/devicetree/bindings/mfd/axp20x.txt
> +++ b/Documentation/devicetree/bindings/mfd/axp20x.txt
> @@ -58,6 +58,11 @@ Optional properties:
>  	      See Documentation/devicetree/bindings/regulator/regulator.txt
>  	      for more information on standard regulator bindings.
>  
> +- backup: An array of two integers for backup battery charging (axp20x-only),
> +	  describing the charging voltage in mV first and the charging current
> +	  in uA second. Backup battery charging is only enabled when these two
> +	  fields are filled.

Well...

We do want to charge batteries other than your backup
battery. Probably this should get separate "backup battery" node with
properties explaining how it is charged?
									Pavel