After upgrading the mint 18 kernel to 4.4.0-87-generic I no longer have wireless. My wired device still works, but my wireless nic has disappeared from ifconfig -a.  It does show up for lspci:02:00.0 Network controller: Broadcom Corporation BCM4352 802.11ac Wireless Network Adapter (rev 03)iwlist scan; lshw -c net*-network UNCLAIMED       description: Network controller       product: BCM4352 802.11ac Wireless Network Adapter       vendor: Broadcom Corporation       physical id: 0       bus info: pci@0000:02:00.0       version: 03       width: 64 bits       clock: 33MHz       capabilities: cap_list       configuration: latency=0       resources: memory:f7200000-f7207fff memory:f7000000-f71fffffIt also shows up in Driver Manager, so I chose the following:Broadcom Corporation: BCM4352 802.11ac Wireless network Adapater:bcmwl-kernel-source (recommended)Version 6.30.223.271 +bdcom-Oubuntu1~1.1Broadcom 201.11 Linux STA wireless driver sourceI tried rebooting and even booting into an earlier kernel, but still my wireless device is unclaimed and does not show up for ipconfig.
Linux mint:Wireless Device Unclaimed after Upgrade
linux mint;wifi;broadcom
this may help, basically...sudo apt-get install firmware-b43-installerand if something like An unsupported BCM4312 Low-Power (LP-PHY) device was found. comes out, then:sudo apt-get install firmware-b43-lpphy-installerHope it helps