Re: [PATCH 1/3] dt-bindings: iio: adc: stm32: add analog switches supply control

[Jonathan Cameron <jic23@kernel.org>]

On Wed, 12 Jun 2019 09:24:34 +0200
Fabrice Gasnier <fabrice.gasnier@st.com> wrote:

> On stm32h7 and stm32mp1, the ADC inputs are multiplexed with analog
> switches which have reduced performances when their supply is below 2.7V
> (vdda by default).
> 
> Add documentation for optional vdda-supply & vdd-supply that can be used
> to supply analog circuitry (controlled by syscfg bits).
> 
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
> ---
>  Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
> index 8346bcb..3af48b9 100644
> --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
> @@ -46,6 +46,12 @@ Required properties:
>  Optional properties:
>  - A pinctrl state named "default" for each ADC channel may be defined to set
>    inX ADC pins in mode of operation for analog input on external pin.
> +- vdda-supply: Phandle to the vdda input voltage. It can be used to supply ADC
> +  analog inputs switches on stm32h7 and stm32mp1.

input switches

> +- vdd-supply: Phandle to the vdd input voltage. It can be used to supply ADC
> +  analog inputs switches on stm32mp1.
> +- st,syscfg: Phandle to system configuration controller. It can be used to
> +  control the analog circuitry on stm32h7 and stm32mp1.
>  
>  Contents of a stm32 adc child node:
>  -----------------------------------