Re: [PATCH v3 2/5] ARM: dts: aspeed: ast2600evb: Add comment for gpio regulator of sdhci

[Andrew Jeffery]

On Thu, 6 May 2021, at 19:33, Steven Lee wrote:
> Add the description for describing the AST2600-A2 EVB reference design of
> GPIO regulators.
> 
> Signed-off-by: Steven Lee <steven_lee at aspeedtech.com>
> ---
>  arch/arm/boot/dts/aspeed-ast2600-evb.dts | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/aspeed-ast2600-evb.dts 
> b/arch/arm/boot/dts/aspeed-ast2600-evb.dts
> index 2772796e215e..1ae0facc3d5f 100644
> --- a/arch/arm/boot/dts/aspeed-ast2600-evb.dts
> +++ b/arch/arm/boot/dts/aspeed-ast2600-evb.dts
> @@ -104,6 +104,21 @@
>  	status = "okay";
>  };
>  
> +/*
> + * The signal voltage of sdhci0 and sdhci1 on AST2600-A2 EVB is able to be
> + * toggled by GPIO pins.
> + * In the reference design, GPIOV0 of AST2600-A2 EVB is connected to the
> + * power load switch that providing 3.3v to sdhci0 vdd, GPIOV1 is connected to
> + * a 1.8v and a 3.3v power load switch that providing signal voltage to
> + * sdhci0 bus.
> + * If GPIOV0 is active high, sdhci0 is enabled, otherwise, sdhci0 is disabled.
> + * If GPIOV1 is active high, 3.3v power load switch is enabled, sdhci0 signal
> + * voltage is 3.3v, otherwise, 1.8v power load switch will be enabled,
> + * sdhci0 signal voltage becomes 1.8v.
> + * AST2600-A2 EVB also support toggling signal voltage for sdhci1.
> + * The design is the same as sdhci0, it uses GPIOV2 as power-gpio and GPIOV3
> + * as power-switch-gpio.
> + */

Okay, I think the comment is in the right place, but I feel this patch 
should also add the regulator nodes and hook them up to the SDHCIs.

Given Rob isn't super keen on a second example in the binding document 
I think you can just cut the example out and paste it in here.

Andrew