fixwifi

#!/bin/sh

#TODO: Pass interface name in as a parameter. Right now wlp3s0 is assumed.

# Figure out what pci slot Linux has assigned the Network controller: Intel Corporation Wireless 7260
wirelessPCI=$(lspci |grep "Wireless 7260")
pci=$(echo ${wirelessPCI} | awk '{ print $1 }')
devicePath="/sys/bus/pci/devices/0000:$pci/remove"

# Not the best solution as this script can hang. 
# But since if this script fails the ONLY way to revive the wifi anyway is a reboot...
# Feel free to improve the script if you have the scriptfu ninja skills to do so.
while true; do

    # Tell Linux to remove the wifi card from the PCI device list only if it exists in the first place.
    if [ -f $devicePath ]; then
        echo 'removing device'
        echo 1 | sudo tee $devicePath > /dev/null
        sleep 1
    fi

    # Reprobe the driver modules in case we have removed them in a failed attempt to wake the network card.
    echo 'reprobing drivers'
    sudo modprobe iwlmvm
    sudo modprobe iwlwifi
    
    # Try to have Linux bring the network card back online as a PCI device. 
    echo 'pci rescan'
    echo 1 | sudo tee /sys/bus/pci/rescan > /dev/null
    sleep 1

    # Check if Linux managed to bring the network card back online as a PCI device.
    if [ -f $devicePath ]; then
        echo 'device is back'

        # Looks like we are back in business. 
        # So we try to set the PCI slot with some voodoo I don't understand that the Intel devs told me to try.
        # https://bugzilla.kernel.org/show_bug.cgi?id=191601
        sudo setpci -s $pci 0x50.B=0x40

        sleep 1
        wifiId=$(rfkill list |grep Wireless |awk -F: '{ print $1 }')
        echo "rfkill unblock wireless device: $wifiId"
        sudo rfkill unblock $wifiId

        sleep 1
        # Bring the wireless network interface up.
        sudo ifconfig wlp3s0 up

        # Did the wifi interface actually go live?
        exitCode=$?
        echo "device UP status $exitCode"
        if [ $exitCode -eq 0 ];then

            # Not sure why in the hell this is not the default for wireless intefaces.
            # It is well documented that: (power_management === ON) === Wifi-Stupidity
            sudo iwconfig wlp3s0 power off

            # The exit code will be the exit code of our attempt at turning power management off for wlp3s0.
            break
        fi
    else
        # It's worse than that the wifi's dead Jim! Dead Jim! Dead!
        # We tell Linux to remove the the wifi driver modules and loop back in an attempt to revive the wifi.
        echo "it's dead Jim"
        sudo modprobe -r iwlmvm
        sudo modprobe -r iwlwifi
    fi
done
⏚