Re: [PATCH v3 5/8] ARM: dts: microchip: sama5d27_wlsom1_ek: Add power-supply property for sdmmc0 node

From: claudiu beznea
Date: Sun Feb 18 2024 - 09:45:48 EST




On 06.02.2024 14:03, Mihai Sain wrote:
> The sdmmc0 controller is powered from 3.3V regulator.

Same here. SDMMC0 data lines are powered by VDDSDHC which could be 1v8/3v3.

[1]
https://ww1.microchip.com/downloads/aemDocuments/documents/MPU32/ProductDocuments/UserGuides/SAMA5D2-Wireless-SOM1-Kit-User%27s-Guide-50002931d.pdf

> Add vmmc-supply and vqmmc-supply properties to sdmmc0 node.
> The sdmmc controller from SAMA5D2 MPU has support for
> IO voltage signaling/switching required by the UHS sd-card.
> In order to avoid the issues from the tuning procedure required by
> the UHS cards, keep the vqmmc at 3V3 to use the sd high-speed mode.
>
> Signed-off-by: Mihai Sain <mihai.sain@xxxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
> index 15239834d886..7b36e1970bb7 100644
> --- a/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
> +++ b/arch/arm/boot/dts/microchip/at91-sama5d27_wlsom1_ek.dts
> @@ -199,6 +199,8 @@ &sdmmc0 {
> bus-width = <4>;
> pinctrl-names = "default";
> pinctrl-0 = <&pinctrl_sdmmc0_default>;
> + vmmc-supply = <&vdd_3v3>;
> + vqmmc-supply = <&vdd_3v3>;
> status = "okay";
> };
>