Hello, I'm experiencing some issues with a FTDI serial-to-usb chip, which becomes unresponsive (the endpoint is halted) while logging this message:
ftdi_sio ttyUSB0: usb_serial_generic_read_bulk_callback - urb stopped: -32 Some searching [1] [2] revealed that I'm not the only one. Most people report this occurring on a Raspberry Pi, however in my case it's a Intel NUC. There seems to be some relationship between bus speed and/or data-rate, but I have not been able to confirm this myself. This issue has been bugging me for almost a year now, and keeps occurring even on kernels as recent as 4.5.1. My current workaround (using libusb) does the following to get the device in working order again: 1 - detach kernel driver 2 - claim interface 3 - call libusb_clear_halt() 4 - call libusb_reset_device() 5 - attach kernel driver This gets the device up and running again. Given the error code above this might not be an appropriate solution, but this does solve the problem (without walking to the machine and re-plugging the device). Any thoughts on how to solve this issue more permanently? I have no idea of the actual cause. [1] https://github.com/raspberrypi/linux/issues/1187 [2] http://comments.gmane.org/gmane.linux.usb.general/111217 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
