preload-wifi.conf

# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

description     "Preload WiFi driver"
author          "chromium-os-dev@chromium.org"

# Run on boot-services; "stay running" until the udev-trigger completes
# (which is guaranteed to happen after boot-services)
start on starting boot-services
stop on stopped udev-trigger

env drvfile=/var/lib/preload-wifi-driver

pre-start script
  # If the driver for built-in WIFI is a module, our post-stop script
  # will have recorded the driver name on the previous boot cycle.
  # Load that driver now so flimflam can config the wireless LAN sooner,
  # ideally by the time login screen is up.
  #
  # Note: failure to probe the module here is NOT fatal.
  if [ -s $drvfile ] ; then
    drv=$(head -1 $drvfile)
    if ! modprobe "$drv" >/dev/null 2>&1 ; then
      # If modprobe didn't like the alias file for some reason, just
      # move it out of the way.  The post-stop script will make a new
      # one.
      mv $drvfile $drvfile.bad
      logger -t "$UPSTART_JOB" \
        "modprobe $drv failed.  Renamed $drvfile with .bad suffix."
    fi
  fi
end script

post-stop script
  # Create/Update driver name for the built-in WIFI.
  # Used to preload WIFI driver in pre-start script.
  # TODO(ggg): can flimflam share the "user selected" network device?
  iwdev=$(iw dev | awk '/Interface/ { print $2 ; exit 0 }')

  if [ -n "$iwdev" ] ; then
    drv=$(ethtool -i "$iwdev" | awk '/driver:/ { print $2 }')
  fi

  if [ -n "$drv" ] ; then
    drvmod=$(lsmod | awk 'd==$1 { print $1 }' d="$drv")
  fi

  if [ -n "$drvmod" ] ; then
    if [ -s $drvfile ] ; then
      olddrv=$(head -1 $drvfile)
    fi

    # Only update contents if they've changed.
    if [ "$drv" != "$olddrv" ] ; then
      echo "$drv" > $drvfile
    fi
  else
    logger -t "$UPSTART_JOB" "$iwdev: $drv is not a module."
  fi
end script