Investigate watchdog timer to work around firmware crashes

HackRF One is recognized and works properly. It's in a system that runs 24/7 to record traffic on a radio network. It works fine, until once every 2 weeks or so it crashes. After it crashes, the "hackrf_info" command (on Ubuntu) says "No HackRF boards found" and the device doesn't show up with the "lsusb" command. I can resolve this issue by pressing the "Reset" button or by unplugging it and reconnecting.

The problem is that this device is in a remote location where I cannot physically interact with it easily. I've looked for ways to programmatically cut the power to the USB port to force a hard reset, but that doesn't seem possible with modern Linux. So, I need the device to either (a) stop crashing, (b) reset itself after it crashes, or (c) allow me to reset it via software.

Steps to reproduce

1. Use the device 24/7 for several weeks
2. Wait for it to crash and stop working

Expected behaviour

It should not crash, or should be recoverable from the crash without having to physically interact with it.

Actual behaviour

I have to press the reset button or unplug it to reset it.

Version information

Operating system: Ubuntu 16.04

hackrf_info output: "No HackRF boards found"

No source file or test is identified. Start by investigating the long-running failure using hackrf_info and lsusb on Ubuntu, then trace the firmware reset or watchdog behavior described in the issue. Done means the HackRF no longer becomes unavailable, or can recover without pressing Reset or unplugging it.