#!/bin/bash
## $Id$
## vim:ts=4:sw=4:nu:ai:nowrap:
##
## Created by Wolfram Schlich <wschlich@gentoo.org>
## Licensed under the GNU GPLv2 or later
##
## Script for being called by udev to activate power and activity LEDs on Atheros cards
##
## Intended to be placed at /lib/udev/ath_led.sh
##
## Example udev rules for a Philips SNN6500 PCMCIA card (802.11abg)
## (e.g. update your /etc/udev/rules.d/70-persistent-net.rules):
## --8<--[ snip ]--8<--
## SUBSYSTEM=="net", DRIVERS=="?*", ATTR{address}=="00:12:bf:12:ab:cd", \
##   ATTR{type}=="1", NAME="ath0"
## SUBSYSTEM=="net", DRIVERS=="?*", ATTR{address}=="00:12:bf:12:ab:cd", \
##   ATTR{type}=="801", RUN+="ath_led.sh -p 1 -a 0"
## --8<--[ snap ]--8<--
## Please note you might change the -p and -a options depending on your card!
##

##
## functions
##

## logs via syslog and optionally stderr
function log() {
	local log_syslog_facility="user"
	local log_syslog_level="${1}"; shift
	local log_syslog_pri="${log_syslog_facility}.${log_syslog_level}"
	local log_syslog_tag="${0##*/}[${$}]" # scriptname[PID]
	local logger_args=
	case "${log_syslog_level}" in
		err|crit|alert|emerg)
			## log err|crit|alert|emerg messages to stderr as well
			logger_args='-s'
			;;
		*)
			;;
	esac
	logger ${logger_args} -p "${log_syslog_pri}" -t "${log_syslog_tag}" <<-EOF
		${@}
		EOF
}

## exits and optionally logs a message
function die() {
	local retval=${1:-1}; shift
	if [[ ${#} -gt 0 ]]; then
		if [[ ${retval} -ne 0 ]]; then
			log crit "${@}"
		else
			log notice "${@}"
		fi
	fi
	exit ${retval}
}

##
## parse command line options
##

#
# -a: activity LED pin (e.g. 0)
# -g: power LED pin (e.g. 1)
#

declare -i act_led_pin=-1 pwr_led_pin=-1
while getopts ':a:p:' opt; do
	case "${opt}" in
		## device data
		a)	declare -i act_led_pin=${OPTARG};;
		p)	declare -i pwr_led_pin=${OPTARG};;
		## option without a required argument
		:)	die 1 "option -${OPTARG} requires an argument";;
		## unknown option
		\?)	die 1 "unknown option -${OPTARG}";;
		## this should never happen
		*)	die 1 "there's an error in the matrix!";;
	esac
done; opt_idx=${OPTIND}; unset OPTIND

##
## main()
##

## check if command line options were given at all
if [[ ${opt_idx} -eq 1 ]]; then
	die 1 "no command line options specified"
fi

## shift options + arguments off the positional parameters
## and process remaining positional parameters
let opt_idx--; shift ${opt_idx}; unset opt_idx
set -- "${@}"

## check for udev environment variable
if [[ -z ${INTERFACE} ]]; then
	die 1 "udev environment variable INTERFACE missing (wifi device)"
fi

## check for required arguments
if [[ -z ${act_led_pin} ]]; then
	die 1 "${INTERFACE}: no activity LED pin specified"
fi
if [[ -z ${pwr_led_pin} ]]; then
	die 1 "${INTERFACE}: no power LED pin specified"
fi

## first, configure power LED
if [[ ${pwr_led_pin} -gt -1 ]]; then
	log info "${INTERFACE}: enabling power LED on pin #${pwr_led_pin}"
	sysctl -q -e -w dev.${INTERFACE}.ledpin=${pwr_led_pin}
	sysctl -q -e -w dev.${INTERFACE}.softled=1
	sysctl -q -e -w dev.${INTERFACE}.softled=0
fi

## second, configure activity LED
if [[ ${act_led_pin} -gt -1 ]]; then
	log info "${INTERFACE}: enabling activity LED on pin #${act_led_pin}"
	sysctl -q -e -w dev.${INTERFACE}.ledpin=${act_led_pin}
	sysctl -q -e -w dev.${INTERFACE}.softled=1
fi

exit 0