Re: [PATCH v2] usb: typec: qcom: Add support for per port VBUS detection

On Thu, Mar 19, 2026 at 02:26:00PM +0100, Konrad Dybcio wrote:

On 3/12/26 7:16 AM, Alexander Koskovich wrote:

quoted

This is required for devices (e.g. ASUS ROG Phone 3) where more than
one USB port can act as a sink and both share a single USBIN input on
the PMIC.

Because the PM8150B uses USBIN to determine VBUS presence, a charger
connected to one port causes the PMIC to falsely detect VBUS on the
other port, preventing it from entering source mode.

For example, plugging a charger into one port prevents using the other
port for a flash drive.

Fix this by adding support for the vbus-gpios connector binding so the
driver can use an external GPIO for per-port VBUS presence detection
instead of the shared USBIN register.

Signed-off-by: Alexander Koskovich <redacted>
---
Changes in v2:
- Dropped RFC prefix
- Remove redundant vbus-detect-gpios, instead use existing vbus-gpios from usb-connector (Dmitry)
- Updated cover to better describe scenario where this change is relevant
- Update comment for EN_TRY_SRC to make more sense
- Skip vSafe5V poll too not just vSafe0V
- return gpiod_get_value_cansleep (Konrad)
- regmap_update_bits -> regmap_set_bits (Konrad)
- Get vbus-gpios per connector (Konrad)
- Add bracket to if (IS_ERR(pmic_typec_port->vbus_detect_gpio)) (Bryan)
- Link to v1: https://lore.kernel.org/r/20260308-qcom-typec-shared-vbus-v1-0-7d574b91052a@pm.me (local)
---
 drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c | 53 +++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c b/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c
index 8051eaa46991..a8f6687a3522 100644
--- a/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c
+++ b/drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c

@@ -5,6 +5,7 @@
 
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/mod_devicetable.h>

@@ -176,6 +177,8 @@ struct pmic_typec_port {
 	bool				vbus_enabled;
 	struct mutex			vbus_lock;		/* VBUS state serialization */
 
+	struct gpio_desc		*vbus_detect_gpio;

I'd like for this to include the word 'secondary', since it's not obvious
that if an external GPIO is at play, we have two ports connected in this
uhh non-standard fashion

perhaps just secondary_vbus_detect_gpio

In theory it can be used even if we have one port.

-- 
With best wishes
Dmitry