[ 120.369992] dwc2 49000000.usb-otg: Overcurrent change detected

[ASkri.1]

Hi!

After starting custom board there are a lot of similar messages in dmesg (10 per second):

[ 200.480616] dwc2 49000000.usb-otg: Overcurrent change detected

....

[ 203.598775] dwc2 49000000.usb-otg: Overcurrent change detected

USB is not working. LED on USB2514B-AEZC hub blinking several times per sec.

What is the reason for this message and how to debug this?

USB_OTG circuit have no visible hardware problems.

Thank you in advance

Looking forward for your reply

[PatrickF]

Hi,

strange behavior as USB2514 is an USB hub (so, connected to USBH) and the log message is for OTG. Maybe some mixed-up in the DT.

could you share your HW schematics around :

• USBH (USB_DP1/DM1 pins) + USB hub (USB2514B-AEZC)
• OTG (I assume USB_DP2/DM2, VBUS, ID)
• VBUS generation for OTG (when in host mode)
• STPMIC1 (if any)

could you share also your uBoot device tree.

See also

• https://wiki.st.com/stm32mpu/wiki/USBH_device_tree_configuration#DT_configuration_when_using_port0_with_a_high-speed_hub
• https://wiki.st.com/stm32mpu/wiki/OTG_device_tree_configuration#DT_configuration_example_as_high_speed_OTG-2C_with_micro-B_connector

Regards

[ASkri.1]

Hi, Patrick!

Thank you very much for quick reply. There are nothing special in the schematic - mostly copy-pasted from ST's reference boards:

USB_HUB connected to USB_DM1 (USB1_N pin of MCU) and USB_DP1 (USB1_P pin of MCU) pins:

OTG connector connected just to USB2_P and USB2_N connector. And currently disconnected.

OTG_VBUS (OSBO_VBUS pin of MCU) currently not connected

VBUS pin of OTG connector connected directly to 5V system power input and used to power target board.

I also suspect problems with DT because I definitely remember, that there was no problems with USB recently

with less customized images on the same board.

Please find attached DT files for my project.

[PatrickF]

Hi,

If your 5V is directly connected to OTG_VBUS pin of STPMIC1, maybe there is some conflict if STPMIC1 OTG_VBUS supply is enabled simultaneously (can explain the over-current detection by STPMIC1).

As you supply your board from OTG connector VBUS, I assume you are in 'peripheral only' on OTG with MicroB connector (similar to STM32MP157F-EV1, i.e. no Type-C nor STUSB1600 as for STM32MP157F-DK2) .

Could you try to add in &usbotg_hs node the two following lines (not 100% sure it is valid for ecosystem v3.0)

dr_mode = "peripheral";
role-switch-default-mode = "peripheral"; 

Note that supplying an MPU board from the USB (without battery in the product, aka 'BUS powered') will likely never pass USB standard certification (many issues linked to power limits during connection, boot time, etc...).

Regards,

[ASkri.1]

Hi, Patrick! Thank you very much for your patience. OTG_VBUS pin of STPMIC1 is not connected at all. It is connected to an unconnected pin of the interface connector. Yes, this is "peripheral only" mode for OTG, so it is normal USB Micro B connector, no USB-C and STUSB1600 Replying to your note, USB connector here is for debug purposes only. I will try to change DT files according to your suggestion, and send reply you you ASAP. Thank you for your support. �?р, 22 �?ент. 2021 г. в 15:22, ST Community :