Wifi cant connect after suspend with highest cpu freq set

[Darth Mowzy]

When I change my cpu frequency to the highest value (2gz) then hibernate and resume I cannot see any access points.

I can get wifi working again by:
     - rebooting
     - changing the cpu scaling to a lower setting then hibernate/resume
     - changing the cpu scaling to a lower setting then `sudo rmmod ath9k; sudo modprobe ath9k;`

I am using Ubuntu 10.04 with ath9k drivers for AR5008.

$ lspci |grep Atheros
0e:00.0 Network controller: Atheros Communications Inc. AR5008 Wireless Network Adapter (rev 01)

$ uname -r
2.6.32-24-generic

$ ifconfig
wlan0 Link encap:Ethernet HWaddr 00:1b:9e:92:7a:46
          UP BROADCAST MULTICAST MTU:1500 Metric:1
          RX packets:258520 errors:0 dropped:0 overruns:0 frame:0
          TX packets:188088 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:312495335 (312.4 MB) TX bytes:21874600 (21.8 MB)
          Interrupt:18 Memory:f8200000-f8210000

$ iwconfig
wlan0 IEEE 802.11g ESSID:off/any
          Mode:Managed Frequency:2.437 GHz Access Point: Not-Associated
          Bit Rate:300 Mb/s
          Power Management:off
          Link Quality:0 Signal level:0 Noise level:0
          Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
          Tx excessive retries:0 Invalid misc:0 Missed beacon:0

$ iwlist wlan0 scan
wlan0 No scan results

[Darth Mowzy (darthmowzy)]

This is similar to this bug https://bugs.launchpad.net/ubuntu/+source/linux-backports-modules-2.6.28/+bug/361178

I already have linux backports generic installed.

[Darth Mowzy (darthmowzy)]

I found out that cpu scaling is causing this issue.

[Darth Mowzy (darthmowzy)]

I installed Linux Mint, which is based on Ubuntu, to separate partition. I installed linux backports. The problem also exists on Linux Mint.

[Darth Mowzy (darthmowzy)]

The issue still exists but I created a workaround using a script to automatically remove and reload ath9k when resuming under /usr/lib/pm-utils/sleep.d

[CODE]#!/bin/sh

. "${PM_FUNCTIONS}"

module="ath9k"

fix_mouse()
{
    echo "\*\*\*\* FIXING THE MOUSE \*\*\*\*"
    /bin/chvt 1
    /bin/chvt 7
    #gtk-update-icon-cache /usr/share/icons/hicolor/
    echo "mouse should be fixed now"
}

fix_wifi()
{
    echo "\*\*\*\* FIXING THE WIFI \*\*\*\*"

    cur_freq=`sudo cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_cur_freq`
    min_freq=`sudo cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq`
    echo "cpu speed is $cur_freq"
    echo "changing cpu speed to $min_freq"
    #cpufreq-selector -f $min_freq #TIME COMMAND TAKES A WHILE FOR SOME REASON
    cpufreq-set -f $min_freq #THIS COMMAND IS FASTER FOR SOME REASON
    echo "cpu speed set to $min_freq"

    echo "sleeping for 1 second"
    sleep 1
    echo "done sleeping"

    echo "removing module $module"
    rmmod $module
    echo "probing module $module"
    modprobe $module

    # echo "changing cpu speed back to $cur_freq"
    # cpufreq-selector -f $cur_freq
}

case "$1" in
    hibernate|suspend)
        echo "BLAH status: $1"
        ;;
    thaw|resume)
        echo "status: $1"
        fix_mouse

        #fix_wifi
        ;;
    *)
        exit $NA
        ;;
esac[/CODE]

Also, cpufreq-selector seems to have a bug which causes it to take 30 seconds to set the cpu speed. So I installed cpufreq-set which works instantly.

[Renate (yollywau)]

My TP-Link PCI-Card is AR 5008.

After pm-suspend, there isn't found the router, no IP. Iwlist scan - nothing. In Ubuntu lucid and maverick, and in aptosid the same problem.
I tried rmmod ath9k before suspend, but it didn't work. The device is found but no IP...
Pm-hibernate works.

[Serge Hallyn (serge-hallyn)]

Please reply if this is still an issue on a supported release.