当我尝试安装 Ubuntu 时，wifi 工作正常，但安装和更新后，我无法连接到 wifi。你能指导我吗？
看到具有类似描述的其他帖子，我运行了 lspci -nn，结果如下。
lspci -nn
00:00.0 Host bridge [0600]: Intel Corporation Mobile 4 Series Chipset Memory Controller Hub [8086:2a40] (rev 07)
00:02.0 VGA compatible controller [0300]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a42] (rev 07)
00:02.1 Display controller [0380]: Intel Corporation Mobile 4 Series Chipset Integrated Graphics Controller [8086:2a43] (rev 07)
00:1a.0 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 [8086:2937] (rev 03)
00:1a.1 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 [8086:2938] (rev 03)
00:1a.2 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 [8086:2939] (rev 03)
00:1a.7 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 [8086:293c] (rev 03)
00:1b.0 Audio device [0403]: Intel Corporation 82801I (ICH9 Family) HD Audio Controller [8086:293e] (rev 03)
00:1c.0 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 1 [8086:2940] (rev 03)
00:1c.1 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 2 [8086:2942] (rev 03)
00:1c.3 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 4 [8086:2946] (rev 03)
00:1c.4 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 5 [8086:2948] (rev 03)
00:1c.5 PCI bridge [0604]: Intel Corporation 82801I (ICH9 Family) PCI Express Port 6 [8086:294a] (rev 03)
00:1d.0 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 [8086:2934] (rev 03)
00:1d.1 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 [8086:2935] (rev 03)
00:1d.2 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 [8086:2936] (rev 03)
00:1d.7 USB controller [0c03]: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 [8086:293a] (rev 03)
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 Mobile PCI Bridge [8086:2448] (rev 93)
00:1f.0 ISA bridge [0601]: Intel Corporation ICH9M LPC Interface Controller [8086:2919] (rev 03)
00:1f.2 SATA controller [0106]: Intel Corporation 82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode] [8086:2929] (rev 03)
00:1f.3 SMBus [0c05]: Intel Corporation 82801I (ICH9 Family) SMBus Controller [8086:2930] (rev 03)
09:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168 PCI Express Gigabit Ethernet controller [10ec:8168] (rev 03)
0c:00.0 Network controller [0280]: Broadcom Corporation BCM4312 802.11b/g LP-PHY [14e4:4315] (rev 01)
0f:00.0 SD Host controller [0805]: Ricoh Co Ltd MMC/SD Host Controller [1180:e822] (rev 01)
0f:00.1 System peripheral [0880]: Ricoh Co Ltd R5U2xx (R5U230 / R5U231 / R5U241) [Memory Stick Host Controller] [1180:e230] (rev 01)
0f:00.3 FireWire (IEEE 1394) [0c00]: Ricoh Co Ltd R5C832 PCIe IEEE 1394 Controller [1180:e832] (rev 01)
答案1
sudo modprobe iwlwifi对我有用。
答案2
您的 Broadcom 需要固件。使用临时以太网连接，请打开终端并执行以下操作：
sudo apt-get install firmware-b43-lpphy-installer
sudo modprobe -r b43 && sudo modprobe b43
一切已准备就绪。