Dear madam, Dear Sir,
We are using an am3703.
Only port 1 of USBHS is used and connected via a TUSB1210 PHY to a Microchip USB2422 hub.
DPLL5 settings have been set according to the values in the errata to solve the cold temperature issue.
Now we observe an issue at high temperature (ambient +50 C) when bus suspend is enabled.
The bus between the HC and hub is suspended more or less every 10 seconds and resumes for 2 seconds in a loop.
After 1-2 hours, the bus fails to resume.
We thought we were seeing the usb suspend/resume issue described in the errata (EHCI Controller: Issue in Suspend Resume Protocol).
We use only one port and have no need for RemoteWakeup so both workarounds can be used.
We have implemented both but to no avail.
We tried even to combine them but still the bus fails to resume.
After that the whole host controller seems to be locked up.
This only happens at high temperature . When we don't use usb bus suspend/resume we have no issues at any temperature.
kindest regards,
Bart Vanderbeke
