-
Type:
Bug
-
Resolution: Fixed
-
Priority:
Medium
-
Linux Core SDK
-
LCPD-17783
-
2019.00
-
07.00.00
-
The USB2PHY Charger Detect function is enabled by default after power on without VBUS presence. This causes D+ to be pulled up, violating the Universal Serial Bus Revision 2.0 Specification.
This violation could cause some USB hubs to not respond to the SETUP packet from the USB host and fail in enumeration if the hub is attached to the SoC’s USB host port prior to the SoC being powered on.
Disable the USB2PHY Charger Detect function by setting the PHY register bit USB2PHY_CHRG_DET[28] MEM_DIS_CHG_DET = 1 prior starting the USB host controller.
See commit 29fc8b24ed2d22ec3db64d9310978a4f9b5c4d87 in u-boot
"phy: omap-usb2-phy: disable phy charger detect"