USB hotplugging

I’m connecting a USB device to the Beaglebone Black. The device (a custom STM32 based board) has a virtual COM port over USB, which naturally appears as /dev/ttyACM0 on the Beagle, as expected.

However, the first time I disconnect the device from the Beagle, I do not get remove events from the Beagle kernel (using udevadm to monitor this). This means that the /dev/ttyACM0 remains.

On reconnecting the device, the remove events finally appear (!), and then the new add events. From here on, disconnects and reconnects do the right thing (the kernel reports remove and add events at the time they happen).

Has anyone else encountered this issue?


USB hot-plugging is a known issue with the 3.8.x kernels on the BBB. You can try using the latest Jessie release if hot-pluggin is important for you.


Thanks for the advice - I switched to using the 3.14.17 kernel (still under Wheezy), and it solved my USB hotplugging issue (not to mention some hub issues I had also encountered).