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How to Install Broadcom / STA Wireless card (BCM43XX)

Wireless doesn’t work on a Broadcom BCM4312

I am new to Ubuntu. I had installed Ubuntu 12.10 on my laptop. Wireless is not working. It is not detecting the available networks. I am able to connect through wire.

Please help me in connecting through wifi.

arun@arunan:~$ lspci

00:00.0 Host bridge: Intel Corporation Mobile 4 Series Chipset Memory Controller Hub (rev 07)

00:02.0 VGA compatible controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)

00:02.1 Display controller: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller (rev 07)

00:1a.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 03)

00:1a.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 (rev 03)

00:1a.2 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 (rev 03)

00:1a.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 (rev 03)

00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03)

00:1c.0 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 (rev 03)

00:1c.1 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 2 (rev 03)

00:1c.2 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 3 (rev 03)

00:1c.4 PCI bridge: Intel Corporation 82801I (ICH9 Family) PCI Express Port 5 (rev 03)

00:1d.0 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 03)

00:1d.1 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 03)

00:1d.2 USB controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 03)

00:1d.7 USB controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 03)

00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev 93)

00:1f.0 ISA bridge: Intel Corporation ICH9M LPC Interface Controller (rev 03)

00:1f.2 SATA controller: Intel Corporation 82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode] (rev 03)

00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev 03)

09:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 02)

0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g LP-PHY (rev 01)

arun@arunan:~$ sudo lshw -c network

*-network UNCLAIMED     

       description: Network controller

       product: BCM4312 802.11b/g LP-PHY

       vendor: Broadcom Corporation

       physical id: 0

       bus info: pci@0000:0c:00.0

       version: 01

       width: 64 bits

       clock: 33MHz

       capabilities: pm msi pciexpress cap_list

       configuration: latency=0

       resources: memory:f69fc000-f69fffff

  *-network

       description: Ethernet interface

       product: RTL8101E/RTL8102E PCI Express Fast Ethernet controller

       vendor: Realtek Semiconductor Co., Ltd.

       physical id: 0

       bus info: pci@0000:09:00.0

       logical name: eth0

       version: 02

       serial: a4:ba:db:de:ce:a2

       size: 100Mbit/s

       capacity: 100Mbit/s

       width: 64 bits

       clock: 33MHz

       capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation

       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full ip=192.168.2.9 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s

       resources: irq:45 ioport:de00(size=256) memory:f0010000-f0010fff memory:f0000000-f000ffff memory:f0020000-f003ffff

arun@arunan:~$ rfkill list all
arun@arunan:~$

The model is Dell Inpsiron 1440

Below are the results which I got when I boot through the live USB and connect to the wireless.

$ sudo lshw -c network

  *-network               

       description: Wireless interface

       product: BCM4312 802.11b/g LP-PHY

       vendor: Broadcom Corporation

       physical id: 0

       bus info: pci@0000:0c:00.0

       logical name: eth1

       version: 01

       serial: 0c:60:76:65:ce:e2

       width: 64 bits

       clock: 33MHz

       capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless

       configuration: broadcast=yes driver=wl0 driverversion=5.100.82.112 ip=192.168.2.10 latency=0 multicast=yes wireless=IEEE 802.11bg

       resources: irq:17 memory:f69fc000-f69fffff

  *-network

       description: Ethernet interface

       product: RTL8101E/RTL8102E PCI Express Fast Ethernet controller

       vendor: Realtek Semiconductor Co., Ltd.

       physical id: 0

       bus info: pci@0000:09:00.0

       logical name: eth0

       version: 02

       serial: a4:ba:db:de:ce:a2

       size: 10Mbit/s

       capacity: 100Mbit/s

       width: 64 bits

       clock: 33MHz

       capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation

       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s

       resources: irq:45 ioport:de00(size=256) memory:f0010000-f0010fff memory:f0000000-f000ffff memory:f0020000-f003ffff