I recently did a full install of Ubuntu 12.04 (not a dual boot) on my laptop. In the past on my dual boot, I connected to a wired ethernet connection with no trouble at all.

Now, my laptop isn't detecting a wired connection when the cable is plugged in. I've tried restarting things and tinkering with files as suggested by other answers with no success.

lspci | egrep -i --color 'network|ethernet'



01:00.0 Ethernet controller: Qualcomm Atheros QCA8172 Fast Ethernet (rev 10)

02:00.0 Network controller: Qualcomm Atheros AR9485 Wireless Network Adapter (rev 01)