The 04/12/2021 15:38, Ulf Hansson wrote:
> On Thu, 8 Apr 2021 at 03:52, Steven Lee <steven_lee@xxxxxxxxxxxxxx> wrote:
> >
> > AST2600-A2 EVB provides the reference design for enabling SD bus power
> > and toggling SD bus signal voltage by GPIO pins.
> > Add the definition and example for power-gpio and power-switch-gpio
> > properties.
> >
> > In the reference design, GPIOV0 of AST2600-A2 EVB is connected to power
> > load switch that providing 3.3v to SD1 bus vdd. GPIOV1 is connected to
> > a 1.8v and a 3.3v power load switch that providing signal voltage to
> > SD1 bus.
> > If GPIOV0 is active high, SD1 bus is enabled. Otherwise, SD1 bus is
> > disabled.
> > If GPIOV1 is active high, 3.3v power load switch is enabled, SD1 signal
> > voltage is 3.3v. Otherwise, 1.8v power load switch will be enabled, SD1
> > signal voltage becomes 1.8v.
> >
> > AST2600-A2 EVB also support toggling signal voltage for SD2 bus.
> > The design is the same as SD1 bus. It uses GPIOV2 as power-gpio and GPIOV3
> > as power-switch-gpio.
>
> Thanks for sharing the details, it certainly helps while reviewing.
>
> >
> > Signed-off-by: Steven Lee <steven_lee@xxxxxxxxxxxxxx>
> > ---
> > .../devicetree/bindings/mmc/aspeed,sdhci.yaml | 25 +++++++++++++++++++
> > 1 file changed, 25 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/mmc/aspeed,sdhci.yaml b/Documentation/devicetree/bindings/mmc/aspeed,sdhci.yaml
> > index 987b287f3bff..515a74614f3c 100644
> > --- a/Documentation/devicetree/bindings/mmc/aspeed,sdhci.yaml
> > +++ b/Documentation/devicetree/bindings/mmc/aspeed,sdhci.yaml
> > @@ -37,6 +37,14 @@ properties:
> > clocks:
> > maxItems: 1
> > description: The SD/SDIO controller clock gate
> > + power-gpio:
> > + description:
> > + The GPIO for enabling/disabling SD bus power.
> > + maxItems: 1
> > + power-switch-gpio:
> > + description:
> > + The GPIO for toggling the signal voltage between 3.3v and 1.8v.
> > + maxItems: 1
>
>
> >
> > patternProperties:
> > "^sdhci@[0-9a-f]+$":
> > @@ -61,6 +69,14 @@ patternProperties:
> > sdhci,auto-cmd12:
> > type: boolean
> > description: Specifies that controller should use auto CMD12
> > + power-gpio:
> > + description:
> > + The GPIO for enabling/disabling SD bus power.
> > + maxItems: 1
> > + power-switch-gpio:
> > + description:
> > + The GPIO for toggling the signal voltage between 3.3v and 1.8v.
> > + maxItems: 1
> > required:
>
> Please do not model these as GPIO pins like this. Instead, it's better
> to model them as gpio regulators, since the mmc core manages them as
> regulators.
>
> We have a vmmc regulator (corresponding to vdd) and a vqmmc regulator
> (corresponding the signal-voltage level). These are also described in
> the common mmc DT bindings, see
> Documentation/devicetree/bindings/mmc/mmc-controller.yaml.
>
Thanks for the information. I will modify it.
> > - compatible
> > - reg
> > @@ -80,6 +96,7 @@ required:
> > examples:
> > - |
> > #include <dt-bindings/clock/aspeed-clock.h>
> > + #include <dt-bindings/gpio/aspeed-gpio.h>
> > sdc@1e740000 {
> > compatible = "aspeed,ast2500-sd-controller";
> > reg = <0x1e740000 0x100>;
> > @@ -94,6 +111,10 @@ examples:
> > interrupts = <26>;
> > sdhci,auto-cmd12;
> > clocks = <&syscon ASPEED_CLK_SDIO>;
> > + power-gpio = <&gpio0 ASPEED_GPIO(V, 0)
> > + GPIO_ACTIVE_HIGH>;
> > + power-switch-gpio = <&gpio0 ASPEED_GPIO(V, 1)
> > + GPIO_ACTIVE_HIGH>;
> > };
> >
> > sdhci1: sdhci@200 {
> > @@ -102,5 +123,9 @@ examples:
> > interrupts = <26>;
> > sdhci,auto-cmd12;
> > clocks = <&syscon ASPEED_CLK_SDIO>;
> > + power-gpio = <&gpio0 ASPEED_GPIO(V, 2)
> > + GPIO_ACTIVE_HIGH>;
> > + power-switch-gpio = <&gpio0 ASPEED_GPIO(V, 3)
> > + GPIO_ACTIVE_HIGH>;
> > };
> > };
>
> Kind regards
> Uffe
