#! /bin/sh
#
# Atempts to reconfigure hda pin configuration after
#  a resume. Audio pin configuration presented here
#  is for a 
#
#  Since pulseaudio grabs the codec, reconfiguration will fail.
#  As such, first we try to stop pulseaudio, then reconfigure
#  pins and finally resume pulseaudio.
#   
# FIXME: There's an obvious racing condition with this idea
#  The autospawn feature of pulseaudio may cause it to relaunch
#  before the pin reconfiguration is performed. Current tests 
#  indicate that this do not occur in practice. Still it would
#  be better to find a more robust solution.
#
#  
#  By Thiago Martins.
#  Adapted the idea of sudoing through
#   pulseaudio users (and copied get_pulse_users)
#   from "01PulseAudio" script on "pulseaudio" debian package
#   by CJ van der Berg 
#

# FIXME: get this dinamically!
HDA_USER_RECONFIG_ROOT=/sys/class/sound/hwC0D0

test_pulse_system() {
    getent passwd pulse | awk -F: '{print $3}'
}

get_pulse_users() {
    PULSE_SYSTEM_USER=$(test_pulse_system)
    if [ -z "${PULSE_SYSTEM_USER}" ]; then
        ps -C pulseaudio -o uid= | tr -d ' '
    else
        ps -C pulseaudio -o uid= | tr -d ' ' | sed s/${PULSE_SYSTEM_USER}//
    fi
}

case $1 in
    thaw|resume)
        # check if there's any user pin config on
        if [ -s ${HDA_USER_RECONFIG_ROOT}/user_pin_configs ] ; then 
	    # Kill pulseaudio for everyone
            for i in $(get_pulse_users); do
                THIS_USER="$(getent passwd ${i} | cut -f1 -d:)"
                su "${THIS_USER}" -c -- 'pulseaudio --kill'
            done
	    # Reset audio pins
	    # For some reason, just writing to reconfig isn't enough
	    TMP_CONFIG_FILE=$(mktemp)
	    cat ${HDA_USER_RECONFIG_ROOT}/user_pin_configs > ${TMP_CONFIG_FILE}
	    cat ${TMP_CONFIG_FILE} > ${HDA_USER_RECONFIG_ROOT}/user_pin_configs
	    rm ${TMP_CONFIG_FILE}
	    echo 1 > ${HDA_USER_RECONFIG_ROOT}/reconfig
	    # Now reenable pulseaudio
            for i in $(get_pulse_users); do
                THIS_USER="$(getent passwd ${i} | cut -f1 -d:)"
                su "${THIS_USER}" -c -- 'pulseaudio --start'
            done
        fi
        ;;
    *) exit $NA
        ;;
esac