USB hotplug problem on iMX28


We are facing some problems when we “hotplug” USB devices on the JumpStart kit for the ConnectCard Wi-i.MX28. When one USB device is connected at startup, everything works great : The USB device is correctly detected by the iMX28.
The problem appears if we plug the USB device when the iMX28 is already started. In this case, an IRQ error appears :

irq 93: nobody cared (try booting with the "irqpoll" option)
[] (fsl_otg_isr+0x0/0x12c)
[] (ehci_fsl_pre_irq+0x0/0x5c)
[] (usb_hcd_irq+0x0/0xa0)
[] (fsl_udc_irq+0x0/0x954)
Disabling IRQ #93

And the device is not recognized by the iMX28.

How can we solve this problem ?

Is this specific to a particular device? I seem to be able to plug USB mouse and keyboard and USB stick and have no problems. What exactly are you plugging in?


We have succeeded in solving this issue. It was a problem of configuration of the jumpers on the JumpStart kit. On our kit, the OTG feature was not activated which results in this IRQ error when one device is hotplugged on the USB.

In order to solve this issue, the jumper P39 must be in shortcut whereas the jumper P37 must be opened.