#! /bin/sh
#
# ctc_configure
#
# Copyright (c) 2017 SUSE LINUX GmbH, Nuernberg, Germany.
#
# Configures a CTC device by calling the IBM-provided chzdev command.
# Whereas this script used to validate the parameters provided to it,
# we now rely on chzdev to do that instead. The script is intended only
# as a "translation layer" to provide backward compatability for older
# scripts and tools that invoke it.
#
# Usage:
#   ctc_configure <read channel> <write channel> <online> [<protocol>]
#
#	read/write channel = x.y.ssss where
#			     x is always 0 until IBM creates something that
#                              uses that number
#			     y is the logical channel subsystem (lcss) number.
#                              Most often this is 0, but it could be non-zero
#			     ssss is the four digit subchannel address of the
#                                 device, in hexidecimal, with leading zeros.
#	online = 0 to take the device offline
#		 1 to bring the device online
#	protocol = 0 Compatibility with peers other than OS/390®, or z/OS, for
#                    example, a z/VM TCP service machine. This is the default.
#		   1 Enhanced package checking for Linux peers.
#		   3 For compatibility with OS/390 or z/OS peers.
#		   4 For MPC connections to VTAM on traditional mainframe
#                    operating systems.
#
# Return values:
#   Return codes are determined by the chzdev command.
#

mesg () {
    echo "$@"
}

debug_mesg () {
    case "${DEBUG}" in
	yes) mesg "$@" ;;
	*) ;;
    esac
}

add_cio_channel() {
	echo "$* # ${DATE}" >> /boot/zipl/active_devices.txt
}

remove_cio_channel() {
	[ -w /boot/zipl/active_devices.txt ] && sed -i -e "/^${1}/d" /boot/zipl/active_devices.txt
}

usage(){
  echo "Usage: ${0} <read channel> <write channel> <online> [<protocol>]"
  echo "	read/write channel = x.y.ssss where"
  echo "			     x is always 0 until IBM creates something that"
  echo "                               uses that number"
  echo "			     y is the logical channel subsystem (lcss) number."
  echo "                               Most often this is 0, but it could be non-zero"
  echo "			     ssss is the four digit subchannel address of the"
  echo "                                  device, in hexidecimal, with leading zeros."
  echo "	online = 0 to take the device offline"
  echo "		 1 to bring the device online"
  echo "	protocol = 0 Compatibility with peers other than OS/390®, or z/OS, for"
  echo "                     example, a z/VM TCP service machine. This is the default."
  echo "		   1 Enhanced package checking for Linux peers."
  echo "		   3 For compatibility with OS/390 or z/OS peers."
  echo "		   4 For MPC connections to VTAM on traditional mainframe"
  echo "                     operating systems."
}

if [ "${DEBUG}" != "yes" ]; then
  DEBUG="no"
fi

DATE=$(date)

CTC_READ_CHAN=${1}
CTC_WRITE_CHAN=${2}
ON_OFF=${3}
CTC_MODE=${4}

if [ -z "${CTC_READ_CHAN}" ] || [ -z "${CTC_WRITE_CHAN}" ] || [ -z "${ON_OFF}" ]; then
  mesg "You didn't specify all the needed parameters."
  usage
  exit 1
fi

if [ -f /sys/bus/ccw/devices/${CTC_READ_CHAN}/cutype ]; then
  read CU_TYPE < /sys/bus/ccw/devices/${CTC_READ_CHAN}/cutype
else mesg "Psuedo file/sys/bus/ccw/devices/${CTC_READ_CHAN}/cutype doesn't exist."
     mesg "Check to see if sysfs is mounted."
     exit 1
fi

PARM_LIST=""
if [ "${CU_TYPE}" == "3088/01" ] || [ "${CU_TYPE}" == "3088/60" ]; then
  DEV_TYPE="lcs"
else DEV_TYPE="ctc"
     if [ -z "${CTC_MODE}" ]; then
       PARM_LIST="${PARM_LIST} protocol=0"
     else PARM_LIST="${PARM_LIST} protocol=${CTC_MODE}"
     fi
fi

if [ "${ON_OFF}" == 0 ]; then
  debug_mesg "chzdev -d ${DEV_TYPE} --no-root-update ${CTC_READ_CHAN}"
  chzdev -d ${DEV_TYPE} --no-root-update ${CTC_READ_CHAN}
elif [ "${ON_OFF}" == 1 ]; then
  debug_mesg "chzdev -e ${DEV_TYPE} --no-root-update ${CTC_READ_CHAN} ${PARM_LIST}"
  chzdev -e ${DEV_TYPE} --no-root-update ${CTC_READ_CHAN} ${PARM_LIST}
else mesg "You must specify a 0 or a 1 for the online/offline attribute."
     usage
     exit 1
fi

RC=${?}
if [ ${RC} -ne 0 ]; then
  exit ${RC}
fi

if [ ${ON_OFF} == 1 ]; then
  add_cio_channel "${CTC_READ_CHAN},${CTC_WRITE_CHAN}"
else remove_cio_channel "${CTC_READ_CHAN}"
     remove_cio_channel "${CTC_WRITE_CHAN}"
fi