Tente isto:
sudo apt-get remove --purge bcmwl-kernel-source
Reinicie e agora diga se brcmsmac está carregado:
lsmod | grep brcm
Fonte: link
Instalei o Ubuntu 16.04 no meu laptop Lenovo B560, mas não consigo descobrir meu wifi, outros dispositivos podem descobrir wifi, esse laptop (16.04) pode descobrir outros wifi na vizinhança. Atualmente eu uso com cartão usb-wifi.
blades@laptop:~$ lspci -nn
00:00.0 Host bridge [0600]: Intel Corporation Core Processor DRAM Controller [8086:0044] (rev 02)
00:02.0 VGA compatible controller [0300]: Intel Corporation Core Processor Integrated Graphics Controller [8086:0046] (rev 02)
00:16.0 Communication controller [0780]: Intel Corporation 5 Series/3400 Series Chipset HECI Controller [8086:3b64] (rev 06)
00:1a.0 USB controller [0c03]: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller [8086:3b3c] (rev 05)
00:1b.0 Audio device [0403]: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio [8086:3b56] (rev 05)
00:1c.0 PCI bridge [0604]: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1 [8086:3b42] (rev 05)
00:1c.1 PCI bridge [0604]: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 2 [8086:3b44] (rev 05)
00:1c.3 PCI bridge [0604]: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 4 [8086:3b48] (rev 05)
00:1d.0 USB controller [0c03]: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller [8086:3b34] (rev 05)
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 Mobile PCI Bridge [8086:2448] (rev a5)
00:1f.0 ISA bridge [0601]: Intel Corporation HM55 Chipset LPC Interface Controller [8086:3b09] (rev 05)
00:1f.2 SATA controller [0106]: Intel Corporation 5 Series/3400 Series Chipset 4 port SATA AHCI Controller [8086:3b29] (rev 05)
00:1f.3 SMBus [0c05]: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller [8086:3b30] (rev 05)
00:1f.6 Signal processing controller [1180]: Intel Corporation 5 Series/3400 Series Chipset Thermal Subsystem [8086:3b32] (rev 05)
03:00.0 Ethernet controller [0200]: Qualcomm Atheros AR8131 Gigabit Ethernet [1969:1063] (rev c0)
04:00.0 Network controller [0280]: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter [14e4:4727] (rev 01)
ff:00.0 Host bridge [0600]: Intel Corporation Core Processor QuickPath Architecture Generic Non-core Registers [8086:2c62] (rev 02)
ff:00.1 Host bridge [0600]: Intel Corporation Core Processor QuickPath Architecture System Address Decoder [8086:2d01] (rev 02)
ff:02.0 Host bridge [0600]: Intel Corporation Core Processor QPI Link 0 [8086:2d10] (rev 02)
ff:02.1 Host bridge [0600]: Intel Corporation 1st Generation Core i3/5/7 Processor QPI Physical 0 [8086:2d11] (rev 02)
ff:02.2 Host bridge [0600]: Intel Corporation 1st Generation Core i3/5/7 Processor Reserved [8086:2d12] (rev 02)
ff:02.3 Host bridge [0600]: Intel Corporation 1st Generation Core i3/5/7 Processor Reserved [8086:2d13] (rev 02)
blades@laptop:~$ lsusb
Bus 002 Device 003: ID 0bda:8172 Realtek Semiconductor Corp. RTL8191SU 802.11n WLAN Adapter
Bus 002 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 004: ID 5986:a002 Acer, Inc
Bus 001 Device 003: ID 1c7a:0801 LighTuning Technology Inc. Fingerprint Reader
Bus 001 Device 002: ID 8087:0020 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
blades@laptop:~$ rfkill list
0: ideapad_wlan: Wireless LAN
Soft blocked: no
Hard blocked: no
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
Tente isto:
sudo apt-get remove --purge bcmwl-kernel-source
Reinicie e agora diga se brcmsmac está carregado:
lsmod | grep brcm
Fonte: link
A solução vem desse post BCM4313 Wireless no Ubuntu Server 12.04
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Oi, meu BCM4313 teve o mesmo problema na semana passada. Acontece que não pega nenhuma rede nos canais 12+. Eu abaixei a rede para o canal 5 e agora ela está trabalhando. - beanaroo Out 28 '12 às 11:20 "