[U-Boot] unable to enumerate USB device on port 2

[Felix Zheng]

Hi guys,

I was using a combination of Gumstix overo and TOBI board. A USB HUB with
external power was connected to the TOBI, so I can use mouse and keyboard
at the same time.

After I updated the uboot (MLO and u-boot.img) recently, the USB port
stopped working. During the boot, I captured some information like this :

Waiting for root device /dev/mmcblk0p2...
hub 2-0:1.0: unable to enumerate USB device on port 2

After the boot process, I can use SSH from another machine to log in. The
following is the dmesg results.

$ dmesg |grep hub
usbcore: registered new interface driver hub
hub 1-0:1.0: usb_probe_interface
hub 1-0:1.0: usb_probe_interface - got id
hub 1-0:1.0: USB hub found
hub 1-0:1.0: 1 port detected
hub 1-0:1.0: standalone hub
hub 1-0:1.0: individual port power switching
hub 1-0:1.0: no over-current protection
hub 1-0:1.0: Single TT
hub 1-0:1.0: TT requires at most 8 FS bit times (666 ns)
hub 1-0:1.0: power on to power good time: 10ms
hub 1-0:1.0: 100mA bus power budget for each child
hub 1-0:1.0: local power source is good
hub 1-0:1.0: enabling power on all ports
hub 1-0:1.0: state 7 ports 1 chg 0000 evt 0000
hub 2-0:1.0: usb_probe_interface
hub 2-0:1.0: usb_probe_interface - got id
hub 2-0:1.0: USB hub found
hub 2-0:1.0: 3 ports detected
hub 2-0:1.0: standalone hub
hub 2-0:1.0: individual port power switching
hub 2-0:1.0: individual port over-current protection
hub 2-0:1.0: power on to power good time: 20ms
hub 2-0:1.0: local power source is good
hub 2-0:1.0: enabling power on all ports
hub 2-0:1.0: port 2: status 0501 change 0001
hub 2-0:1.0: state 7 ports 3 chg 0004 evt 0000
hub 2-0:1.0: port 2, status 0501, change 0000, 480 Mb/s
hub 2-0:1.0: port 2 not reset yet, waiting 50ms
hub 2-0:1.0: unable to enumerate USB device on port 2
hub 2-0:1.0: state 7 ports 3 chg 0000 evt 0004

It is obvious that this is not a hardware problem, because all I changed
are just from old MLO, u-boot.bin to new MLO and u-boot.img. The same type
of 16GB SD cards were used here.
I have already changed the mmcrootfstype type back to ext3 so it can boot.
I have checked several previous posts, but they were just facing hardware
problems or bugs between different linux kernels.

So does anybody know, is there any other setting I need to fix when I
update the two uboot files?

Thanks for your help,
Felix