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

[Thinh Nguyen]

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 at jmu.edu.cn>
> ---
>  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
>