#!/bin/sh

# These definitions must match the definitions in sis1100_var.h
MINORBITS=8
MINORCARDBITS=2
MINORTYPEBITS=2
MINORUSERBITS=`expr $MINORBITS - $MINORCARDBITS - $MINORTYPEBITS`

# minornumber: ccccttuu

# number of cards we really want to use
MAXCARDS=4
# how often we want to open the same device
MAXUSER=2

modulename=sis1100

basename=${modulename}_
devdir=/tmp
mode=666
owner=root
group=root

types0="remote"
types1="ram"
types2="ctrl"
types3="dsp"

mkname () {
    card=$1
    type=$2
    user=$3
    tname=`eval echo \\\$types$type`
    name=$devdir/${basename}`printf '%d%d' $card $user`$tname
    echo $name
}

shiftv () {
    val=$1
    i=$2
    while [ $i -gt 0 ]; do
        val=`expr $val \* 2`
        i=`expr $i - 1`
    done
    echo $val
}

if [ "$MAXCARDS" = "" ]; then
    MAXCARDS=`shiftv 1 $MINORCARDBITS`
fi
#echo MAXCARDS $MAXCARDS

CARDSHIFT=`expr $MINORUSERBITS + $MINORTYPEBITS`
TYPESHIFT=$MINORUSERBITS
MAXTYPES=`shiftv 1 $MINORTYPEBITS`
#echo MAXTYPES $MAXTYPES
if [ "MAXUSER" = "" ]; then
    MAXUSER=`shiftv 1 $USERBITS`
fi
#echo MAXUSER $MAXUSER

make_devs () {
    if grep -q $modulename /proc/devices; then
        major=`cat /proc/devices | awk "\\$2==\"$modulename\" {print \\$1}"`
        echo -e \\n$modulename major: $major
        #echo $modulename major: $major
    else
        echo -e \\n$modulename not loaded!
        return
    fi

    rm -f $devdir/${basename}*

    card=`expr $MAXCARDS - 1`
    while [ $card -ge 0 ]; do
        #echo card $card
        type=`expr $MAXTYPES - 1`
            while [ $type -ge 0 ]; do
                #echo "  " type $type
                user=`expr $MAXUSER - 1`
                while [ $user -ge 0 ]; do
                    #echo "    " user $user
                    cardbits=`shiftv $card $CARDSHIFT`
                    typebits=`shiftv $type $TYPESHIFT`
                    minorbits=`expr $cardbits + $typebits + $user`
                    #echo "      " bits `printf '%x' $minorbits`
                    name=`mkname $card $type $user`
                    #echo mknod $name c $major $minorbits
                    mknod $name c $major $minorbits
                    user=`expr $user - 1`
                done
                type=`expr $type - 1`
            done
        card=`expr $card - 1`
    done

    chown $owner $devdir/${basename}*
    chgrp $group $devdir/${basename}*
    chmod $mode $devdir/${basename}*
}

case "$1" in
start)
    echo -n "Creating device files for $modulename"
    make_devs
    echo "."
    ;;
stop)
    rm -f $devdir/${basename}*
    ;;
*)
    echo "Usage: /etc/init.d/sis1100 {start|stop}"
    exit 1
esac

exit 0