On 12/23/19 9:07 AM, Ley Foon Tan wrote:
In Cyclone 5 SoC platform, the first USB probing is failed but second probing is success. DWC2 driver read gsnpsid register right after de-assert reset, but controller is not ready yet and it returns gsnpsid 0. Adding small delay after de-assert reset solve the issue.
Retry with this fix more than 10 times without issue.
=> usb reset resetting USB... Bus usb@ffb40000: usb probe SNPSID invalid (not DWC2 OTG device): 00000000 Port not available. => usb reset resetting USB... Bus usb@ffb40000: usb probe scanning bus usb@ffb40000 for devices... 2 USB Device(s) found scanning usb for storage devices... 1 Storage Device(s) found
Can't you poll for the readiness of the IP somehow instead of using arbitrary delay ?