[MacBook Air 4,1] Wireless scan fails to see APs on DFS channels

[Seth Forshee]

The BCM43224 wireless in this machine has the regulatory domain "X0" stored in its ROM, which is apparently a custom Broadcom domain. This gets passed up to mac80211 as a regulatory hint, but since the domain is unknown mac80211 ends up applying the world domain, which has the DFS channels in the 5 GHz band disabled.

The solution is probably that brcmsmac needs to gain support for the Broadcom-custom regulatory domains.

WORKAROUND: You can enable passive scanning on the DFS channels manually from userspace by running "sudo iw reg set <alpha-2>". E.g., for the US domain run "sudo iw reg set US".

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: linux-image-3.2.0-18-generic 3.2.0-18.28
ProcVersionSignature: Ubuntu 3.2.0-18.28-generic 3.2.9
Uname: Linux 3.2.0-18-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.94.1-0ubuntu1
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: PCH [HDA Intel PCH], device 0: Cirrus Analog [Cirrus Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: sforshee 1873 F.... pulseaudio
Card0.Amixer.info:
 Card hw:0 'PCH'/'HDA Intel PCH at 0xa0600000 irq 47'
   Mixer name : 'Intel CougarPoint HDMI'
   Components : 'HDA:10134206,106b6200,00100302 HDA:80862805,80860101,00100000'
   Controls : 29
   Simple ctrls : 9
Date: Thu Mar 8 15:23:21 2012
EcryptfsInUse: Yes
HibernationDevice: RESUME=UUID=df8148cd-dd0f-4ab0-8c7f-95b373e85e2c
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64+mac (20111208)
MachineType: Apple Inc. MacBookAir4,1
ProcEnviron:
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-18-generic root=UUID=f4af0efe-df4b-4d74-8995-7081cf79889c ro crashkernel=384M-2G:64M,2G-:128M quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.2.0-18-generic N/A
 linux-backports-modules-3.2.0-18-generic N/A
 linux-firmware 1.71
SourcePackage: linux
StagingDrivers: mei
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/14/2011
dmi.bios.vendor: Apple Inc.
dmi.bios.version: MBA41.88Z.0077.B0E.1110141154
dmi.board.asset.tag: Base Board Asset Tag#
dmi.board.name: Mac-C08A6BB70A942AC2
dmi.board.vendor: Apple Inc.
dmi.board.version: MacBookAir4,1
dmi.chassis.type: 10
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-C08A6BB70A942AC2
dmi.modalias: dmi:bvnAppleInc.:bvrMBA41.88Z.0077.B0E.1110141154:bd10/14/2011:svnAppleInc.:pnMacBookAir4,1:pvr1.0:rvnAppleInc.:rnMac-C08A6BB70A942AC2:rvrMacBookAir4,1:cvnAppleInc.:ct10:cvrMac-C08A6BB70A942AC2:
dmi.product.name: MacBookAir4,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 3.5.0-2.2

---------------
linux (3.5.0-2.2) quantal-proposed; urgency=low

  [ Andy Whitcroft ]

  * rebase to v3.5-rc4

  [ Arend van Spriel ]

  * SAUCE: (drop after 3.5) brcmsmac: fix NULL pointer crash in
    brcms_c_regd_init()
    - LP: #950320

  [ Bryan Wu ]

  * [Config] Sync CONFIG_CGROUP_MEM_RES_CTLR_SWAP for ARM

  [ Chris J Arges ]

  * PACKAGING: add .gnu_debuglink sections to .ko files
    - LP: #669641

  [ Leann Ogasawara ]

  * d-i: Add hid-generic to input-modules
    - LP: #1017879

  [ Ming Lei ]

  * SAUCE: Revert "mmc: omap_hsmmc: Enable Auto CMD12"
    - LP: #1017717, #225

  [ Paolo Pisati ]

  * SAUCE: Revert "Fix OMAP EHCI suspend/resume failure (i693)"
    - LP: #1017718
  * [Config] Disable generic USB_EHCI_HCD_PLATFORM on omap3

  [ Seth Forshee ]

  * SAUCE: (drop after 3.5) brcm80211: smac: don't set up tx power limits
    during initialization
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: always set channel specified
    by mac80211
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: remove unused code for 40MHz
    channels
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: clean up channel.c
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: inform mac80211 of the X2
    regulatory domain
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: enable/disable radio on
    regulatory updates
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: use mac80211 channel data for
    tx power limits
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: don't validate channels
    against internal regulatory data
    - LP: #950320
  * SAUCE: (drop after 3.5) brcm80211: smac: use current regulatory domain
    when checking whether OFDM is allowed
    - LP: #950320

  [ Tim Gardner ]

  * [Config] Enable CONFIG_CGROUPS for highbank
    - LP: #1014692
  * [Config] FB_OMAP*=y and PANEL_TFP410=y

  [ Upstream Kernel Changes ]

  * rebase to v3.5-rc4
 -- Leann Ogasawara <email address hidden> Tue, 26 Jun 2012 06:21:05 -0700

[Adam Conrad (adconrad)]

The verification of this Stable Release Update has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regresssions.