8086:4222 [Dell Precision M4300] Intel wifi led is off after resuming from suspend

[Cas]

I have set the wifi "options iwlegacy led_mode=1" in /etc/modprobe.d/wlan.conf to stop the led blinking, which works as expected. The problem I have found is that if I suspend the laptop then upon resuming the wifi led is permanently off yet the wifi still works properly.

Also it is not just suspend that affects the LED, disabling wifi from network menu or using the hardware wifi switch on the laptop results it the same problem that the LED is permanently off after turning wifi back on.

This is regression going from kernel 2.6.38 (Natty) to 2.6.39 (Oneiric).

Note: I am not sure if it was clear enough that when the led is set to blinking there is no issue with it being off upon resume etc.

WORKAROUND: To get the LED back on without rebooting reload the module:
rmmod iwl3945 && modprobe iwl3945

WORKAROUND: For the suspend issue is to add to /etc/pm/config.d/modules :
SUSPEND_MODULES="iwl3945"

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: linux-image-3.5.0-10-generic 3.5.0-10.10
ProcVersionSignature: Ubuntu 3.5.0-10.10-generic 3.5.1
Uname: Linux 3.5.0-10-generic x86_64
ApportVersion: 2.4-0ubuntu8
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: calum 1921 F.... pulseaudio
CRDA:
 country GB:
  (2402 - 2482 @ 40), (N/A, 20)
  (5170 - 5250 @ 40), (N/A, 20)
  (5250 - 5330 @ 40), (N/A, 20), DFS
  (5490 - 5710 @ 40), (N/A, 27), DFS
CheckboxSubmission: beb20350994a383f56f97def0e07bae1
CheckboxSystem: d00f84de8a555815fa1c4660280da308
Date: Thu Aug 16 19:23:53 2012
HibernationDevice: RESUME=UUID=3f279429-3482-4734-86b6-cc41fa7ce020
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120223.1)
MachineType: Dell Inc. Precision M4300
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
ProcFB: 0 nouveaufb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-10-generic root=UUID=64e61881-95ee-4b3c-8714-c08c940f4966 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.5.0-10-generic N/A
 linux-backports-modules-3.5.0-10-generic N/A
 linux-firmware 1.89
SourcePackage: linux
UpgradeStatus: Upgraded to quantal on 2012-08-12 (3 days ago)
dmi.bios.date: 06/19/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A17
dmi.board.name: 0UY141
dmi.board.vendor: Dell Inc.
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA15:bd01/20/2010:svnDellInc.:pnPrecisionM4300:pvr:rvnDellInc.:rn0UY141:rvr:cvnDellInc.:ct8:cvr:
dmi.product.name: Precision M4300
dmi.sys.vendor: Dell Inc.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v3.6 kernel[0] (Not a kernel in the daily directory) and install both the linux-image and linux-image-extra .deb packages.

Once you've tested the upstream kernel, please remove the 'needs-upstream-testing' tag. Please only remove that one tag and leave the other tags. This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the 'needs-upstream-testing' text.

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

If you are unable to test the mainline kernel, for example it will not boot, please add the tag: 'kernel-unable-to-test-upstream'.
Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.6-rc1-quantal/

[Joseph Salisbury (jsalisbury)]

This issue appears to be an upstream bug, since you tested the latest upstream kernel. Would it be possible for you to open an upstream bug report[0]? That will allow the upstream Developers to examine the issue, and may provide a quicker resolution to the bug.

If you are comfortable with opening a bug upstream, It would be great if you can report back the upstream bug number in this bug report. That will allow us to link this bug to the upstream report.

[0] https://wiki.ubuntu.com/Bugs/Upstream/kernel

[Cas (calumlind)]

Since this is a kernel issue the BIOS update is irrelevant to this issue but I did it anyway and the issue persists.

I just now reported it upstream to wireless mailing list so will see what happens there.

[Cas (calumlind)]

I said that I updated to A17 (06/19/2013) and re-tested so I don't know why you are reverting the changes.

[Cas (calumlind)]

I narrowed this down to working in kernel 2.6.38 (Natty) but stopped working in 3.0 onwards.

Also it is not just suspend that affects the LED, using the hardware wifi switch on the laptop results it the same problem that the LED is permanently off after turning wifi back on.

The only way to get the LED back on without rebooting is to reload the module: `rmmod iwl3945 && modprobe iwl3945`

Thus a workaround for the suspend issue is to add SUSPEND_MODULES="iwl3945" to /etc/pm/config.d/modules

[Cas (calumlind)]

I did... A17 06/19/2013

[Cas (calumlind)]

I have narrowed the problem further to commits in 2.6.39, likely somewhere in the splitting of iwl3945 drivers into iwlegacy directory[1]

I am struggling to get any further narrowing it down as either I am facing kernel build issues or wireless is not working on the builds that are in the middle of iwlegacy commits.

I will report this upstream and update with url.

[1] https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/log/drivers/net/wireless/iwlegacy?h=linux-2.6.39.y

[Cas (calumlind)]

I have reported this upstream and there is no indication either from bug report or rc3 commits that it is fixed yet.

[penalvch (penalvch)]

Cas, thank you for testing mainline kernel v3.13-rc3. Unfortunately, there are issues with both your downstream and upstream report.

First, while you tested a more recent mainline kernel, the most recent one is http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.13-rc5-trusty/ . Could you please test this and advise to the results?

As well, if reproducible in this, given this is a wifi related issue, could you please the latest development release from the linux-next tree via http://drvbp1.linux-foundation.org/~mcgrof/rel-html/backports/ ?

Thank you for your understanding.