I have been troubleshooting an issue with USB which appears to happen with AM3517, OMAP3530, and DM3730 in which the USB doesn't detect removal or connection of USB devices and interrupts stop occurring. In every case, I have the OMAP3 EHCI connected to a USB3220 transceiver which is treated as configured in the device tree as usb-nop-xceiv with reset-gpios configured to enable it. When I connect and disconnect peripherals like thumb drives, keyboards, mice, etc., directly to the USB port, the system seems to behave as I would expect. If I connect a hub with a device already connected to it, the system recognizes the attached device peripheral -> external hub -> transceiver -> omap3-ehci If I disconnect the hub from the OMAP, it also sees the disconnection and subsequent reconnection. However, if I connect a hub with nothing attached to the hub, I get the following message: ehci-omap 48064800.ehci: suspend root hub At this point, no disconnection or reconnection are ever recognized, and no further interrupts are recorded on the ehci-omap from /proc/interrupts. If I pass "optargs usbcore.autosuspend=-1" to as a command line parameter, the system works as expected. I have been able to replicate this issue with multiple external hubs, and I am beginning to test this work-around with different hubs, but it seems like disabling autosuspend is a hack. I was wondering if there might be a better solution and/or suggestions as to what needs to happen to poll the USB occasionally to see if there are devices present. Thanks adam
