[PATCH v2 1/4] riscv: dts: spacemit: k1-bananapi-f3: Add vcc5v0_sys regulator for Banana Pi F3

[Anand Moon]

Hi Yixun,

Thanks for your review comments.

On Thu, 7 May 2026 at 08:15, Yixun Lan <dlan at kernel.org> wrote:
>
> Hi Anand,
>
> On 10:48 Sat 02 May     , Anand Moon wrote:
> > Define the system 5V fixed regulator (vcc5v0_sys) supplied by the
> > DC input. As per the schematics, vcc5v0_sys is the input power source
> > for the VCC5V0_HUB and 5V_VBUS reglators. Update these regulators
> > to correctly reference vcc5v0_sys as their parent (vin-supply).
> >
> > Cc: Han Gao <gaohan at iscas.ac.cn>
> > Cc: Ze Huang <huang.ze at linux.dev>
> > Cc: Chukun Pan <amadeus at jmu.edu.cn>
> > Signed-off-by: Anand Moon <linux.amoon at gmail.com>
> > ---
> >  arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> >
> > diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> > index 5790d927b93d..9727ecdd9f6b 100644
> > --- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> > +++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> > @@ -50,6 +50,16 @@ reg_dc_in: regulator-dc-in-12v {
> >               regulator-always-on;
> >       };
> >
> > +     reg_vcc5v0_sys: regulator-vcc5v0-sys {
> This will fall into the catogery of "non-controllable & serve no devices"
> see similar comment for 'reg_dc_in' which raised by Krzysztof
>
> https://lore.kernel.org/all/6530526f-59ca-4753-a068-46c62a1a1fed@kernel.org/
>
> or should I ask, what's the real problem if regulator has no vin-supply?

If the device tree is not configured with the correct power source it
will affect performance.

> Any probe failure or something bad happen? (besides /sys/../regulator_summay)

Not really; the regulator summary just confirms the PMIC used the
correct power source.
with te device ip blocks.

Bananapi F3 schematics.
[1] https://drive.google.com/file/d/19iLJ5xnCB_oK8VeQjkPGjzAn39WYyylv/view
(page 24)

Please check the shematics VCC5V0_SYS page 4
VCC5V0_SYS->USB_VCC5V0->HDMI_VCC5V0->FAN_VCC5V0->VCC3V3_SYS

Please check the shematics VCC5V0_SYS page 24
VCC5V0_SYS input for VCC5V0_HUB and 5V_VBUS give the USB hub,
which is enabled by USB3_PWREN (gpio pin)>

Plese check power tree page 4
USBVBUS->SY8386J UXXX -> PCIE_VCC3V3 for pcie vin source

So, this series tries to fix the vin source for USB 3.0 and PCIe nodes.

Thanks
-Anand
>
> > +             compatible = "regulator-fixed";
> > +             regulator-name = "vcc5v0_sys";
> > +             regulator-min-microvolt = <5000000>;
> > +             regulator-max-microvolt = <5000000>;
> > +             regulator-boot-on;
> > +             regulator-always-on;
> > +             vin-supply = <&reg_dc_in>;
> > +     };
> > +
> >       reg_vcc_4v: regulator-vcc-4v {
> >               compatible = "regulator-fixed";
> >               regulator-name = "vcc_4v";
> > @@ -66,6 +76,7 @@ regulator-usb3-vbus-5v {
> >               regulator-min-microvolt = <5000000>;
> >               regulator-max-microvolt = <5000000>;
> >               regulator-always-on;
> > +             vin-supply = <&reg_vcc5v0_sys>;
> >               gpio = <&gpio K1_GPIO(97) GPIO_ACTIVE_HIGH>;
> >               enable-active-high;
> >       };
> > @@ -75,6 +86,7 @@ usb3_hub_5v: regulator-usb3-hub-5v {
> >               regulator-name = "USB30_HUB";
> >               regulator-min-microvolt = <5000000>;
> >               regulator-max-microvolt = <5000000>;
> > +             vin-supply = <&reg_vcc5v0_sys>;
> >               gpio = <&gpio K1_GPIO(123) GPIO_ACTIVE_HIGH>;
> >               enable-active-high;
> >       };
> > --
> > 2.50.1
> >
>
> --
> Yixun Lan (dlan)