The USB OTG port of the RK3308 exibits a bug when:

 - configured as peripheral, and
 - used in gadget mode, and
 - the USB cable is connected since before booting

The symptom is: about 6 seconds after configuring gadget mode the device is
disconnected and then re-enumerated. This happens only once per boot.

Investigation showed that in this configuration the charger detection code
turns off the PHY after 6 seconds. Patch 1 avoids this when a cable is
connected (VBUS present).

After patch 1 the connection is stable but communication stops after 6
seconds. this is addressed by patch 2.

The topic had been discussed in [0]. Thanks Alan and Minas for the
discussion and Louis for having found the 1st issue, leading to patch 1.

[0] https://lore.kernel.org/lkml/20250414185458.7767aabc@booty/ (local)

Luca

Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
---
Louis Chauvet (1):
      phy: rockchip: inno-usb2: fix disconnection in gadget mode

Luca Ceresoli (1):
      phy: rockchip: inno-usb2: fix communication disruption in gadget mode

 drivers/phy/rockchip/phy-rockchip-inno-usb2.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)
---
base-commit: 15240745d6cd14183d112249a9fff87fb968b859
change-id: 20250718-rk3308-fix-usb-gadget-phy-disconnect-d7de71fb28b4

Best regards,
-- 
Luca Ceresoli [off-list ref]