A few days ago, the USB ports in my laptop stop working.  At first, I thought it might be due to a recent update of my OS (Ubuntu 14.04), so I began testing if something came up when connecting a wireless mouse while checking the dmesg output. Not even a message related to the USB port in the output, tough.If there's no output for dmesg while testing some peripherals, I can conclude that the problem is due to hardware (a.k.a. broken USB ports), or there's some other way to prove that this can be a software problem?
How can I find out if a problem with the USB ports in my laptop is due to hardware or software?
usb;dmesg