Re: arm64: dts: rockchip: Add SDR104 mode to SD-card I/F on rk3399-roc-pc

[Ulf Hansson <ulf.hansson@linaro.org>]

On Mon, 11 Nov 2019 at 20:32, Markus Reichl <m.reichl@fivetechno.de> wrote:
>
> Hi Ulf,
>
> Am 11.11.19 um 18:27 schrieb Ulf Hansson:
> > On Mon, 11 Nov 2019 at 15:13, Markus Reichl <m.reichl@fivetechno.de> wrote:
> >>
> >> Add SDR104 capability and regulators to SD card node.
> >> While at it, fix a typo in lcd pinctrl and remove two
> >> undocumented bindings from pmic.
> >>
> >> Signed-off-by: Markus Reichl <m.reichl@fivetechno.de>
> >> ---
> >>  .../boot/dts/rockchip/rk3399-roc-pc.dtsi      | 31 +++++++++++++++----
> >>  1 file changed, 25 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> >> index 33df95e384b4..e86a6db54499 100644
> >> --- a/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> >> +++ b/arch/arm64/boot/dts/rockchip/rk3399-roc-pc.dtsi
> >> @@ -135,6 +135,20 @@
> >>                 vin-supply = <&vcc_1v8>;
> >>         };
> >>
> >> +       vcc3v0_sd: vcc3v0-sd {
> >> +               compatible = "regulator-fixed";
> >> +               enable-active-high;
> >> +               gpio = <&gpio4 RK_PD6 GPIO_ACTIVE_HIGH>;
> >> +               pinctrl-names = "default";
> >> +               pinctrl-0 = <&vcc3v0_sd_en>;
> >> +               regulator-name = "vcc3v0_sd";
> >> +               regulator-always-on;
> >
> > This looks odd. A GPIO regulator being always on?
>
> This is a standard micro SD card socket that can also be used for
> booting the board. I wanted to be cautious and start
> working with it and several SD cards and explore the capabilities.
>
> On this board nearly all regulators are still continously
> switched on. I plan to remove the always-on properties step
> by step from the regulators when the board runs stable with it's
> components all enbled.
>
> >
> >> +               regulator-boot-on;
> >> +               regulator-min-microvolt = <3000000>;
> >> +               regulator-max-microvolt = <3000000>;
> >> +               vin-supply = <&vcc3v3_sys>;
> >> +       };
> >
> > Assumes this powers an SDIO embedded card. Often those have a specific
> > power sequence, just wanted to make sure the above are really
> > sufficient? No delays or external clock needed?
>
> It's not embedded, just a standard µSD plug. It is already enabled
> by mainline U-Boot and ejecting and inserting the card works fine.

Ah, thanks for confirming.

Kind regards
Uffe