[PATCH v2 3/3] riscv: dts: spacemit: Enable USB3.0 on BananaPi-F3

[Samuel Holland]

Hi Ze,

On 2026-01-08 10:07 PM, Ze Huang wrote:
> On Thu, Jan 08, 2026 at 07:36:05PM +0800, Yixun Lan wrote:
>> Hi Ze,
>>
>> I've done a quick check of the "regulator-always-on" issue, 
>> it's ok to drop the one from hub, but not the vbus one..
>>
> 
> Thanks for your double check
> 
>> On 09:21 Thu 08 Jan     , Yixun Lan wrote:
>>> Hi Ze,
>>>
>>>   thanks for your patch, I have few comments, see below..
>>>
>>> On 20:05 Wed 07 Jan     , Ze Huang wrote:
>>>> Enable the DWC3 USB 3.0 controller and its associated usbphy2 on the
>>>> Banana Pi F3 board.
>>>>
>>>> The board utilizes a VLI VL817 hub, which requires two separate power
>>>> supplies: one VBUS and one for hub itself. Add two GPIO-controlled
>>>> fixed-regulators to manage this.
>>>>
>>>> Tested-by: Aurelien Jarno <aurelien at aurel32.net>
>>>> Signed-off-by: Ze Huang <huang.ze at linux.dev>
>>>> ---
>>>>  arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts | 48 +++++++++++++++++++++++++
>>>>  1 file changed, 48 insertions(+)
>>>>
>>>> diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
>>>> index 3f10efd925dc..013df91c6a4c 100644
>>>> --- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
>>>> +++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
>>>> @@ -59,6 +59,26 @@ reg_vcc_4v: vcc-4v {
>>>>  		regulator-always-on;
>>>>  		vin-supply = <&reg_dc_in>;
>>>>  	};
>>>> +
>>>> +	usb3_vbus: regulator-vbus-5v {
>>> I've checked the schematics, the name is 5V_VBUS there, so for the consistency
>>> with previous naming convention, let's change to:
>>> 	usb3_vbus_5v: usb3-vbus-5v 
>>>
>>>> +		compatible = "regulator-fixed";
>>>> +		regulator-name = "USB30_VBUS";
>>>> +		regulator-min-microvolt = <5000000>;
>>>> +		regulator-max-microvolt = <5000000>;
>>> ..
>>>> +		regulator-always-on;
>>> do you think the "always-on" property really necessary? it indicate the
>>> power regulator is critical, and should never been disabled even during
>>> suspend/resume state, for the case of USB, I think it should be totally
>>> fine to poweroff once the device is not used(suspended) or even disabled
>>>
>>> besides, the regulator is designed with a gpio enabling/disabling control
>>> which means it can be powered to on/off state?
>>>
> 
> 
>> not ok to drop, see comment below at &usb_dwc3 
> 
>>
>>>> +		gpio = <&gpio K1_GPIO(97) GPIO_ACTIVE_HIGH>;
>>>> +		enable-active-high;
>>>> +	};
>>>> +
>>>> +	usb3_vhub: regulator-vhub-5v {
>>> why use vhub, but not hub? where does this name come from?
>>>
>>> and for same reason, the name in schematics is VCC5V0_HUB, so how about
>>> change it to:
>>> 	usb3_hub_5v: usb3-hub-5v 
>>>
>>>> +		compatible = "regulator-fixed";
>>>> +		regulator-name = "USB30_VHUB";
>>>                                     ~~~need to fix too, if above is valid
>>>> +		regulator-min-microvolt = <5000000>;
>>>> +		regulator-max-microvolt = <5000000>;
>>> ..
>>>> +		regulator-always-on;
>>> ditto
> 
>> ok to drop, as it's already handled at drivers/usb/misc/onboard_usb_dev.c
>> which will explicitly request the regulator and enable it
> 
>>
>>>> +		gpio = <&gpio K1_GPIO(123) GPIO_ACTIVE_HIGH>;
>>>> +		enable-active-high;
>>>> +	};
>>>>  };
>>>>  
>>>>  &combo_phy {
>>>> @@ -67,6 +87,34 @@ &combo_phy {
>>>>  	status = "okay";
>>>>  };
>>>>  
>>> ..
>>>> +&usbphy2 {
>>>> +	status = "okay";
>>>> +};
>>>> +
>>>> +&usb_dwc3 {
>>>> +	dr_mode = "host";
>>>> +	vbus-supply = <&usb3_vbus>;
>> due to drivers/usb/dwc3/dwc3-generic-plat.c has no handler to request regulator
>> there will be problem if "regulator-always-on" property is removed..
> 
> On the BananaPi-F3 and to Jupiter, the VL817 hub setup uses two distinct controls:
> 
> GPIO97  controls the physical VBUS supply.
> GPIO123 controls the VCC5V0_HUB supply for the hub logic.
> 
> (Note: This differs from the Orange Pi RV2, where only GPIO123 is used to
> control the VBUS supply).
> 
> dwc3-generic-plat can not currently handle the regulator request explicitly,
> keeping "regulator-always-on" forces the VBUS to remain active even when
> suspended, which consumes unnecessary power.
> 
> I prefer to drop regulator-always-on in the DTS to accurately describe the
> hardware capability, and let the driver manage the VBUS state. This ensures
> better power management.
> 
> If anyone have other ideas, please let me know.

If a USB device requires board-level resources to function, then the USB device
itself (not the controller) needs a DT node that references these resources.
This is the purpose of the usb-device.yaml binding. For the VL817 hub, there is
a specific binding that links the highspeed and superspeed hubs together. See
Documentation/devicetree/bindings/usb/vialab,vl817.yaml. These nodes are matched
with the Linux usb-onboard-hub driver.

Regards,
Samuel