Legacy Wireless Chipsets broken with macOS Monterey

[khronokernel]

With macOS Monterey, Apple seems to have changed some sections of their Networking stack including:

• Renaming IO80211Family to IO80211FamilyLegacy
• Renaming IO80211FamilyV2 to IO80211Family

This looks to be the initial mark of Apple depreciating their legacy Broadcom support used with the BCM94360 and BCM94350 chipsets located in 2017 and older Macs. Currently newer Intel Macs use the AppleBCMWLANBusInterfacePCIeMac kext for networking support.

With this change, it seems to have broken the entirely of our El Capitan, High Sierra and Mojave wireless networking kexts and thus heavily limiting what wireless chipsets can be used with Monterey even through a patcher. The issue manifest is loss of Networking Scanning and in some scenarios even kernel panics on boot.

Currently we're unsure exactly where the root cause lies, however other networking kexts such as Apple's built-in i210 and SmallTree's i211 kexts are also broken.

Affected Models

Currently the following chipsets are affected

• All Atheros Chipets
• Broadcom BCM94328
• Broadcom BCM94322

The following models shipped with these cards:

• iMac12,x and older
• Macmini3,1 and older
• MacBook5,x and older
• MacBookAir2,1 and older
• MacBookPro7,1 and older (6,x excluded)
• MacPro5,1 and older

Work Arounds

Currently the only known work around for Monterey support is to upgrade to a newer wireless chipset. The following are native or can be easily patched with OpenCore Legacy Patcher:

• Broadcom BCM943224
  • Requires OpenCore to re-enable support in Big Sur and newer
• Broadcom BCM94331
  • Requires OpenCore to re-enable support in Big Sur and newer
• Broadcom BCM94360
• Broadcom BCM94602

[houser42]

Just a report that the Broadcom BCM94360CSAX is working great so far in a MacBook Pro mid 2012 as far as wifi goes
at ac good speeds. This is with macOS 12.0 (21A5304g) public beta.

Bluetooth just one left side channel so far in apple headphones. FWIW.