On Thu, 7 Apr 2011, Enric Balletbà i Serra wrote: > Hi all, > > I'm experimenting some issues with USB on IGEP v2 board, in certain > cases I've an USB disconnect when I plug a device. For me it fails > with kernel 2.6.35 but I think it also affect newer kernel, the issue > is easy to reproduce following these steps: > > 1. Power up the board (without any device connected ) > > 2. When kernel is up, connect a powered USB HUB 2.0 to the USB host > port, kernel shows, > > usb 1-1: new high speed USB device using ehci-omap and address 2 > usb 1-1: New USB device found, idVendor=05e3, idProduct=0608 > usb 1-1: New USB device strings: Mfr=0, Product=1, SerialNumber=0 > usb 1-1: Product: USB2.0 Hub > hub 1-1:1.0: USB hub found > hub 1-1:1.0: 4 ports detected > usb 1-1.4: new high speed USB device using ehci-omap and address 3 > usb 1-1.4: New USB device found, idVendor=05e3, idProduct=0608 > usb 1-1.4: New USB device strings: Mfr=0, Product=1, SerialNumber=0 > usb 1-1.4: Product: USB2.0 Hub > hub 1-1.4:1.0: USB hub found > hub 1-1.4:1.0: 4 ports detected > > 3. Then if I connect a device (for example a pendrive) to the HUB I > get USB disconnect message > > usb 1-1: USB disconnect, address 2 > usb 1-1.4: USB disconnect, address 3 > > OTOH, it works without problem > 1. if power up the board with the USB HUB connected to the USB Host > port and the device connected to the USB hub. > 2. if after kernel is up, connect the USB HUB + device to the USB Host port > > Anyone is experimenting something like this with other OMAP3-based boards ? At first glance, it looks like a power-related issue. Current inrush when the device is plugged in, or something like that. What happens if you attach the hub and pendrive to a standard PC? Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
