#!/bin/bash
#
# rtirq_power: save and restore irq process priorities
#
# This script is called when a change in power status happens, when
# suspending it saves a list of all irq process priorities, when
# resuming it changes the priorities of the proper irq processes
# to the saved values
#
# Copyright (c) 2012 Fernando Lopez-Lezcano
#
#   This program is free software; you can redistribute it and/or
#   modify it under the terms of the GNU General Public License
#   as published by the Free Software Foundation; either version 2
#   of the License, or (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License along
#   with this program; if not, write to the Free Software Foundation, Inc.,
#   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

. "${PM_FUNCTIONS}"

case $1 in
    hibernate|suspend)
	/bin/ps -eo rtprio=,comm= --sort -rtprio | /bin/egrep ' irq/[0-9]*' | savestate rtirq
        ;;
    thaw|resume)
	restorestate rtirq | while read IRQPRIO IRQCOMM ; do
	    if [ -n "${IRQPRIO}" -a -n "${IRQCOMM}" ] ; then
		IRQPID=`/bin/ps -e -o pid,comm | grep " ${IRQCOMM}" | awk '{print $1}'`
		if [ -n "${IRQPID}" ] ; then
		    PRIO=`/bin/ps -p ${IRQPID} -o rtprio=`
		    if [ ${PRIO} -ne ${IRQPRIO} ] ; then
			/usr/bin/chrt -f -p ${IRQPRIO} ${IRQPID}
		    fi
		fi
	    fi
	done
        ;;
    *) exit $NA
        ;;
esac