Re: [PATCH] ARM: dts: rockchip: correct regular setting for act8846

Heiko Stuebner
2017-05-24T11:35:42Z

Am Mittwoch, 24. Mai 2017, 11:26:10 CEST schrieb Robin Murphy:
> On 24/05/17 09:17, Heiko Stuebner wrote:
> > Hi Eddie,
> >
> > Am Mittwoch, 24. Mai 2017, 15:33:41 CEST schrieb Eddie Cai:
> >> the previous setting of act8846 is just copy from firefly board. but
> >> the reload board is a little different from firefly board. let's correct
> >> it.
> >>
> >> Signed-off-by: Eddie Cai <eddie.cai.linux@gmail.com>
> >> ---
> >> arch/arm/boot/dts/rk3288-firefly-reload-core.dtsi | 21 +++++++++++----------
> >> 1 file changed, 11 insertions(+), 10 deletions(-)
> >>
> >> diff --git a/arch/arm/boot/dts/rk3288-firefly-reload-core.dtsi b/arch/arm/boot/dts/rk3288-firefly-reload-core.dtsi
> >> index 8134966..4cfa109 100644
> >> --- a/arch/arm/boot/dts/rk3288-firefly-reload-core.dtsi
> >> +++ b/arch/arm/boot/dts/rk3288-firefly-reload-core.dtsi
> >> @@ -179,6 +179,7 @@
> >> regulator-name = "vccio_sd";
> >> regulator-min-microvolt = <3300000>;
> >> regulator-max-microvolt = <3300000>;
> >> + regulator-always-on;
> >
> > the rest below looks pretty straight forward, but why does vccio_sd
> > need to be always on?
> >
> > I've checked the reload's schematics but did not find any further users
> > of vccio_sd that may warant this attribute.
>
> It looks like the card detect line is pulled up externally to vcc_sd,
> which isn't always-on either, so you probably do want this - on the
> (unrelated) rk3288 TV box I've been hacking on, I discovered that
> powering off the sdmmc-supply domain also kills the internal pull-up and
> leaves sdmmc_cd floating. The resulting stochastic card polling
> mechanism is amusing, but probably undesirable ;)

Hmm, are you mixing up vcc_sd and vccio_sd?

vccio_sd is the io supply (vqmmc in mmc-terms) to the mmc-host itself
while vcc_sd is the actual card supply (vmmc in mmc-terms).

After looking through some schematics, the pull-up to vcc_sd seems to be
the common pattern for rk3288 devices. So I guess this means the fixed
regulator vcc_sd should get an regulator-always-on instead to stabilize
the card-detect?

Heiko

> >
> >
> > Heiko
> >
> >
> >> };
> >>
> >> vdd10_lcd: REG6 {
> >> @@ -187,24 +188,23 @@
> >> regulator-max-microvolt = <1000000>;
> >> };
> >>
> >> - vcca_18: REG7 {
> >> - regulator-name = "vcca_18";
> >> - regulator-min-microvolt = <1800000>;
> >> - regulator-max-microvolt = <1800000>;
> >> - regulator-always-on;
> >> + vcca_33: REG7 {
> >> + regulator-name = "vcca_33";
> >> + regulator-min-microvolt = <3300000>;
> >> + regulator-max-microvolt = <3300000>;
> >> };
> >>
> >> - vcca_33: REG8 {
> >> - regulator-name = "vcca_33";
> >> + vcc_lan: REG8 {
> >> + regulator-name = "vcc_lan";
> >> regulator-min-microvolt = <3300000>;
> >> regulator-max-microvolt = <3300000>;
> >> - regulator-always-on;
> >> };
> >>
> >> - vcc_lan: REG9 {
> >> - regulator-name = "vcca_lan";
> >> + vccio_pmu: REG9 {
> >> + regulator-name = "vccio_pmu";
> >> regulator-min-microvolt = <3300000>;
> >> regulator-max-microvolt = <3300000>;
> >> + regulator-always-on;
> >> };
> >>
> >> vdd_10: REG10 {
> >> @@ -218,6 +218,7 @@
> >> regulator-name = "vcc_18";
> >> regulator-min-microvolt = <1800000>;
> >> regulator-max-microvolt = <1800000>;
> >> + regulator-always-on;
> >> };
> >>
> >> vcc18_lcd: REG12 {
> >>
> >
> >
> >
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> >
>
>
>