The ASUS ROG Phone 3 has two USB-C ports whose VBUS lines are both
wired to the single USBIN input on the PM8150B PMIC. This means the
Type-C port controller cannot distinguish which port is providing
VBUS, causing one port to be unusable when the other has VBUS present
from a charger or PC.

The downstream vendor driver also appears to be touching
TYPE_C_CRUDE_SENSOR_CFG_REG for restoring CC detection after enabling
BYPASS_VSAFE0V but does not appear to be necessary with the upstream
TCPM stack?

Feedback on whether additional register configuration is needed would be
appreciated, but functionally this appears to work as is. After these
changes and configuring the property in DTS I am able to use a flash
drive on the side USB port (pm8150b_typec) while I am connected to a
charger or my PC via the bottom USB port (rt1715).

Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
---
Alexander Koskovich (2):
      dt-bindings: usb: qcom,pmic-typec: Document vbus-detect-gpios property
      usb: typec: qcom: Add support for shared USBIN VBUS detection

 .../devicetree/bindings/usb/qcom,pmic-typec.yaml   |  6 +++
 drivers/usb/typec/tcpm/qcom/qcom_pmic_typec_port.c | 46 +++++++++++++++++++++-
 2 files changed, 50 insertions(+), 2 deletions(-)
---
base-commit: 11439c4635edd669ae435eec308f4ab8a0804808
change-id: 20260308-qcom-typec-shared-vbus-7d37c6b2d155

Best regards,
-- 
Alexander Koskovich <akoskovich@pm.me>

On 08/03/2026 23:20, Alexander Koskovich wrote:
> The ASUS ROG Phone 3 has two USB-C ports whose VBUS lines are both
> wired to the single USBIN input on the PM8150B PMIC. This means the
> Type-C port controller cannot distinguish which port is providing
> VBUS, causing one port to be unusable when the other has VBUS present
> from a charger or PC.

Hrmm..

If you have a GPIO for VBUS detect then who is sourcing VBUS in host mode ?

There should be a GPIO to switch it on aswell ? And in this case both 
ports will become "hot" at the same time.

How does VBUS work in host mode here ?

---
bod

On Wednesday, March 11th, 2026 at 10:53 AM, Bryan O'Donoghue <bryan.odonoghue@linaro.org> wrote:

> On 08/03/2026 23:20, Alexander Koskovich wrote:
> > The ASUS ROG Phone 3 has two USB-C ports whose VBUS lines are both
> > wired to the single USBIN input on the PM8150B PMIC. This means the
> > Type-C port controller cannot distinguish which port is providing
> > VBUS, causing one port to be unusable when the other has VBUS present
> > from a charger or PC.
> 
> Hrmm..
> 
> If you have a GPIO for VBUS detect then who is sourcing VBUS in host mode ?
> 
> There should be a GPIO to switch it on aswell ? And in this case both
> ports will become "hot" at the same time.

For the side port this is the PM8150B's internal OTG regulator which is gated
onto the connector with an external load switch controlled by GPIO 11
(downstream calls this POGO_OTG_EN).

For the bottom port there's an independent boost converter which is gated by
GPIO 71 (downstream calls this BTM_OTG_EN), and doesn't have anything to do
with the PM8150B OTG output.

For the ROG 3 I've modeled these in DTS as vreg_pm8150b_vbus & vreg_rt1715_vbus,
so they're the vbus-supply for each TCPM.

> 
> How does VBUS work in host mode here ?

When a USB device is plugged into one port CC detection sees the phone as
source, and the OTG GPIO for the port is asserted to enable 5V.

The VBUS detect GPIO won't read as active for this since OTG power takes a
different path than the OVP ICs (2x BQ25968).

> 

Also here's a link to the downstream driver for reference: https://github.com/LineageOS/android_kernel_asus_sm8250/blob/lineage-19.1/drivers/power/supply/qcom/smb5-lib.c

> ---
> bod
> 
>

On 11/03/2026 17:37, Alexander Koskovich wrote:
> For the bottom port there's an independent boost converter

Ahh..

OK for some reason I read your mail and thought that the PM8150b was 
sourcing VBUS for both ports, after realising you had a RT1715 aka 
reading your cover letter again.

So much for my research on how to make that esoteric setup work.

---
bod