Re: [PATCH v2 1/1] usb: dwc3: Add optional VBUS regulator support to SpacemiT K1

From: Thinh Nguyen

Date: Mon Mar 23 2026 - 21:43:16 EST


On Fri, Mar 20, 2026, Chukun Pan wrote:
> Some SpacemiT K1 boards (like OrangePi R2S) provide USB VBUS
> through a controllable regulator. Add support for the optional
> vbus-supply property so the regulator can be properly managed
> in host mode instead of left always-on. Note that this doesn't
> apply to USB Hub downstream ports with different VBUS supplies.
>
> The enabled and disabled actions of the regulator are handled
> automatically by devm_regulator_get_enable_optional().
>
> Signed-off-by: Chukun Pan <amadeus@xxxxxxxxxx>
> ---
> drivers/usb/dwc3/dwc3-generic-plat.c | 22 +++++++++++++++++++++-
> 1 file changed, 21 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc3/dwc3-generic-plat.c b/drivers/usb/dwc3/dwc3-generic-plat.c
> index e846844e0023..bd281fde5ce0 100644
> --- a/drivers/usb/dwc3/dwc3-generic-plat.c
> +++ b/drivers/usb/dwc3/dwc3-generic-plat.c
> @@ -12,6 +12,8 @@
> #include <linux/reset.h>
> #include <linux/regmap.h>
> #include <linux/mfd/syscon.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/usb/otg.h>
> #include "glue.h"
>
> #define EIC7700_HSP_BUS_FILTER_EN BIT(0)
> @@ -69,6 +71,20 @@ static int dwc3_eic7700_init(struct dwc3_generic *dwc3g)
> return 0;
> }
>
> +static int dwc3_spacemit_k1_init(struct dwc3_generic *dwc3g)
> +{
> + struct device *dev = dwc3g->dev;
> +
> + if (usb_get_dr_mode(dev) == USB_DR_MODE_HOST) {
> + int ret = devm_regulator_get_enable_optional(dev, "vbus");
> +
> + if (ret && ret != -ENODEV)
> + return dev_err_probe(dev, ret, "failed to enable VBUS\n");
> + }
> +
> + return 0;
> +}
> +
> static int dwc3_generic_probe(struct platform_device *pdev)
> {
> const struct dwc3_generic_config *plat_config;
> @@ -210,10 +226,14 @@ static const struct dwc3_generic_config eic7700_dwc3 = {
> .properties = DWC3_DEFAULT_PROPERTIES,
> };
>
> +static const struct dwc3_generic_config spacemit_k1_dwc3 = {
> + .init = dwc3_spacemit_k1_init,

Set .properties = DWC3_DEFAULT_PROPERTIES,

> +};
> +
> static const struct of_device_id dwc3_generic_of_match[] = {
> - { .compatible = "spacemit,k1-dwc3", },
> { .compatible = "fsl,ls1028a-dwc3", &fsl_ls1028_dwc3},
> { .compatible = "eswin,eic7700-dwc3", &eic7700_dwc3},
> + { .compatible = "spacemit,k1-dwc3", &spacemit_k1_dwc3},

Any reason for moving this to the bottom? To avoid cherry-pick/rebase
conflict in the future, can we place this where it was before?

The rest looks good.

Thanks,
Thinh

> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
> --
> 2.34.1
>