Re: [PATCH RFC 2/2] usb: typec: qcom: Add support for shared USBIN VBUS detection

[Konrad Dybcio]

On 3/9/26 12:20 AM, Alexander Koskovich wrote:
> On devices with multiple USB-C ports whose VBUS lines are wired to a
> single shared USBIN input on the PM8150B PMIC (e.g. ASUS ROG Phone 3), the
> Type-C port controller cannot distinguish which port is providing VBUS.
> 
> In practice this shows up as being unable to use the affected Type-C port
> while the other port is connected to a device providing VBUS such as a PC
> or charger.
> 
> Add support for an optional vbus-detect-gpios property that allows the
> Type-C port controller to read VBUS state from a per-port GPIO instead of
> the shared USBIN input. When present, the driver also bypasses VSAFE0V
> checks and switches DRP toggling to TRY_SRC to avoid false source
> detection caused by VBUS present on USBIN from another port.
> 
> Signed-off-by: Alexander Koskovich <akoskovich@xxxxx>
> ---

[...]

> +	if (pmic_typec_port->vbus_detect_gpio) {
> +		vbus = gpiod_get_value_cansleep(pmic_typec_port->vbus_detect_gpio);
> +		return vbus;

"return gpiod_..."

[...]

> +	/*
> +	 * On devices with multiple USB-C ports sharing USBIN, bypass
> +	 * VSAFE0V so SRC attachment can complete despite VBUS being
> +	 * present on USBIN from another port.
> +	 */
> +	if (pmic_typec_port->vbus_detect_gpio) {
> +		ret = regmap_update_bits(pmic_typec_port->regmap,
> +					 pmic_typec_port->base + TYPEC_EXIT_STATE_CFG_REG,
> +					 BYPASS_VSAFE0V_DURING_ROLE_SWAP,
> +					 BYPASS_VSAFE0V_DURING_ROLE_SWAP);

regmap_set_bits()



> +		if (ret)
> +			goto done;
> +	}
> +
>  	pmic_typec_port->tcpm_port = tcpm_port;
>  
>  	for (i = 0; i < pmic_typec_port->nr_irqs; i++)
> @@ -724,6 +760,12 @@ int qcom_pmic_typec_port_probe(struct platform_device *pdev,
>  	if (IS_ERR(pmic_typec_port->vdd_vbus))
>  		return PTR_ERR(pmic_typec_port->vdd_vbus);
>  
> +	pmic_typec_port->vbus_detect_gpio = devm_gpiod_get_optional(dev, "vbus-detect",
> +								 GPIOD_IN);

I thought the intent here was to have 2 GPIOs, one per port - could
you please shed some light on this?

Konrad