diff --git a/meta-phosphor/scripts/run-repotest b/meta-phosphor/scripts/run-repotest
index 27bf738..6d6d23b 100755
--- a/meta-phosphor/scripts/run-repotest
+++ b/meta-phosphor/scripts/run-repotest
@@ -129,30 +129,6 @@
 meta-ibm/recipes-phosphor/chassis/vrm-control/vrm-control.sh
 meta-inventec/meta-transformers/recipes-phosphor/init/transformers-init/transformers-init.sh
 meta-phosphor/recipes-support/nss-pam-ldapd/files/nslcd.init
-meta-quanta/meta-common/recipes-quanta/network/usb-network/usb-network.sh
-meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-update.sh
-meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-verify.sh
-meta-quanta/meta-gbs/recipes-gbs/gbs-bmc-update/files/bmc-verify.sh
-meta-quanta/meta-gbs/recipes-gbs/gbs-detect-gpio-present/files/detect-gpio-present.sh
-meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-sysinit.sh
-meta-quanta/meta-gbs/recipes-gbs/hotswap-power-cycle/files/tray_powercycle.sh
-meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-check-host-state.sh
-meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-set-failsafe.sh
-meta-quanta/meta-gbs/recipes-phosphor/fans/phosphor-pid-control/fan-table-init.sh
-meta-quanta/meta-gbs/recipes-phosphor/sensors/phosphor-nvme/nvme_json_rewrite.sh
-meta-quanta/meta-gsj/recipes-gsj/detect-fan-fail/files/detect-fan-fail.sh
-meta-quanta/meta-gsj/recipes-gsj/gsj-hotswap-change-setting/files/gsj-hotswap-change-setting.sh
-meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/init_once.sh
-meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
-meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powermanager.sh
-meta-quanta/meta-gsj/recipes-gsj/usb-network/files/usb_network.sh
-meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-control.sh
-meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-default-speed.sh
-meta-quanta/meta-olympus-nuvoton/recipes-olympus-nuvoton/power/first-boot-set-psu/first-boot-set-psu.sh
-meta-quanta/meta-olympus-nuvoton/recipes-phosphor/fans/phosphor-pid-control/fan-full-speed.sh
-meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/init_once.sh
-meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweroff.sh
-meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweron.sh
 "
 
 types=(json shell)
diff --git a/meta-quanta/meta-common/recipes-quanta/network/usb-network/usb-network.sh b/meta-quanta/meta-common/recipes-quanta/network/usb-network/usb-network.sh
index ebd6f02..8fc28cc 100644
--- a/meta-quanta/meta-common/recipes-quanta/network/usb-network/usb-network.sh
+++ b/meta-quanta/meta-common/recipes-quanta/network/usb-network/usb-network.sh
@@ -6,25 +6,25 @@
 
 check_usb_local_administered() {
     is_enable="$(cat ${mac_config} | grep 'USBLAA')"
-    echo ${is_enable}
+    echo "${is_enable}"
 }
 
 # Set the locally administered bit (the second least-significant
 # bit of the first octet) of the MAC address
 set_local_administered_bit() {
-    mac="$(tr -d '\0' < $1)"
+    mac="$(tr -d '\0' < "$1")"
     first_byte="${mac:0:2}"
     first_byte="$((0x$first_byte|2))"
     first_byte="$(printf "%02x\n" "$first_byte")"
     mac="${first_byte}${mac:2}"
-    echo $mac
+    echo "$mac"
 }
 
-cd /sys/kernel/config/usb_gadget
+cd /sys/kernel/config/usb_gadget || exit 1
 
 if [ ! -f "g1" ]; then
     mkdir g1
-    cd g1
+    cd g1 || exit 1
 
     echo 0x1d6b > idVendor  # Linux foundation
     echo 0x0104 > idProduct # Multifunction composite gadget
@@ -41,8 +41,8 @@
     if [[ $(check_usb_local_administered) == "USBLAA=true" ]]; then
         dev_mac="$(set_local_administered_bit $dev_mac_path)"
         host_mac="$(set_local_administered_bit $host_mac_path)"
-        echo $dev_mac > $dev_mac_path
-        echo $host_mac > $host_mac_path
+        echo "$dev_mac" > $dev_mac_path
+        echo "$host_mac" > $host_mac_path
     fi
 
     mkdir -p functions/ecm.usb0
diff --git a/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-update.sh b/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-update.sh
index bf71e94..32a595f 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-update.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-update.sh
@@ -28,14 +28,9 @@
 # the node of FIU is spi for kernel 5.10, but
 # for less than or equal kernel 5.4, the node
 # is fiu
-for fname in $(find ${KERNEL_SYSFS_FIU} -type l)
-do
-    if [ "${fname##*\.}" == "fiu" ]
-    then
-        KERNEL_FIU_ID="c0000000.fiu"
-        break
-    fi
-done
+if ls "$KERNEL_SYSFS_FIU"/*.fiu 1> /dev/null 2>&1; then
+  KERNEL_FIU_ID="c0000000.fiu"
+fi
 
 IMAGE_FILE="/tmp/image-bios"
 
@@ -45,7 +40,7 @@
     m=$(grep -xl "$1" /sys/class/mtd/*/name)
     m=${m%/name}
     m=${m##*/}
-    echo $m
+    echo "$m"
 }
 
 cleanup() {
@@ -82,8 +77,7 @@
         exit 1
     fi
 
-    flashcp -v $IMAGE_FILE /dev/"${bios_mtd}"
-    if [ $? -eq 0 ]; then
+    if flashcp -v $IMAGE_FILE /dev/"${bios_mtd}" ; then
         echo "bios update successfully..."
     else
         echo "bios update failed..."
@@ -91,6 +85,6 @@
     fi
 }
 # Exit without running main() if sourced
-return 0 2>/dev/null
-
-main "$@"
+if ! (return 0 2>/dev/null); then
+    main "$@"
+fi
diff --git a/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-verify.sh b/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-verify.sh
index 3da25e4..ac4ee1d 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-verify.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/gbs-bios-update/files/bios-verify.sh
@@ -14,11 +14,11 @@
 
 if [ -e $IMAGE_FILE ] && [ -e $SIG_FILE ];
 then
-    sha256_image=`sha256sum "$IMAGE_FILE" | awk '{print $1}'`
-    sha256_file=`awk '{print $1}' $SIG_FILE`
+    sha256_image=$(sha256sum "$IMAGE_FILE" | awk '{print $1}')
+    sha256_file=$(awk '{print $1}' $SIG_FILE)
 fi
 
-if [[ $sha256_image != $sha256_file ]];
+if [ "$sha256_image" != "$sha256_file" ];
 then
     echo "bios image verify fail."
     rm -f $IMAGE_FILE
diff --git a/meta-quanta/meta-gbs/recipes-gbs/gbs-bmc-update/files/bmc-verify.sh b/meta-quanta/meta-gbs/recipes-gbs/gbs-bmc-update/files/bmc-verify.sh
index bbaf15d..d45105d 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/gbs-bmc-update/files/bmc-verify.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/gbs-bmc-update/files/bmc-verify.sh
@@ -9,7 +9,7 @@
 if [ -f $publickey ];then
     r="$(openssl dgst -verify $publickey -sha256 -signature $sigfile $bmcimage)"
     echo "$r" > $bmclog
-    if [[ "Verified OK" == "$r" ]]; then
+    if [ "Verified OK" = "$r" ]; then
         mv $bmcimage $imagebmc
         rm -f $sigfile
         exit 0
diff --git a/meta-quanta/meta-gbs/recipes-gbs/gbs-detect-gpio-present/files/detect-gpio-present.sh b/meta-quanta/meta-gbs/recipes-gbs/gbs-detect-gpio-present/files/detect-gpio-present.sh
index cb652a2..b1bc46e 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/gbs-detect-gpio-present/files/detect-gpio-present.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/gbs-detect-gpio-present/files/detect-gpio-present.sh
@@ -27,24 +27,24 @@
 LOG_GENID_FLAG="0x0020"
 present_state=("true" "true" "true" "true" "true" "true" "true" "true" "true" "true" "true" "true")
 
-for i in ${!PRESENT_OBJPATH[@]}
+for i in "${!PRESENT_OBJPATH[@]}"
 do
-    mapper wait ${PRESENT_OBJPATH[$i]}
+    mapper wait "${PRESENT_OBJPATH[$i]}"
 done
 
 while true; do
-    for i in ${!PRESENT_OBJPATH[@]}
+    for i in "${!PRESENT_OBJPATH[@]}"
     do
-        boot_status="$(busctl get-property $SERVICE_NAME ${PRESENT_OBJPATH[$i]} $INTERFACE_NAME Present | awk '{print $2}')"
+        boot_status="$(busctl get-property $SERVICE_NAME "${PRESENT_OBJPATH[$i]}" $INTERFACE_NAME Present | awk '{print $2}')"
 
-        if [ $boot_status == "false" ] && [ ${present_state[$i]} == "true" ];then
-            echo "Update cable $(($i+1)) state."
-            present_state[$i]="false"
-            busctl call $IPMI_LOG_SERVICE $IPMI_LOG_OBJPATH $IPMI_LOG_INTERFACE $IPMI_LOG_FUNCT $IPMI_LOG_PARA_FORMAT "$LOG_ERR" ${PRESENT_OBJPATH[$i]} $LOG_EVENT_DATA $LOG_ASSERT_FLAG $LOG_GENID_FLAG
-        elif [ $boot_status == "true" ] && [ ${present_state[$i]} == "false" ];then
-            echo "Update cable $(($i+1)) state."
-            present_state[$i]="true"
-            busctl call $IPMI_LOG_SERVICE $IPMI_LOG_OBJPATH $IPMI_LOG_INTERFACE $IPMI_LOG_FUNCT $IPMI_LOG_PARA_FORMAT "$LOG_ERR" ${PRESENT_OBJPATH[$i]} $LOG_EVENT_DATA $LOG_DEASSERT_FLAG $LOG_GENID_FLAG
+        if [ "$boot_status" == "false" ] && [ "${present_state[$i]}" == "true" ];then
+            echo "Update cable $((i+1)) state."
+            present_state[i]="false"
+            busctl call $IPMI_LOG_SERVICE $IPMI_LOG_OBJPATH $IPMI_LOG_INTERFACE $IPMI_LOG_FUNCT $IPMI_LOG_PARA_FORMAT "$LOG_ERR" "${PRESENT_OBJPATH[$i]}" "$LOG_EVENT_DATA" $LOG_ASSERT_FLAG $LOG_GENID_FLAG
+        elif [ "$boot_status" == "true" ] && [ "${present_state[$i]}" == "false" ];then
+            echo "Update cable $((i+1)) state."
+            present_state[i]="true"
+            busctl call $IPMI_LOG_SERVICE $IPMI_LOG_OBJPATH $IPMI_LOG_INTERFACE $IPMI_LOG_FUNCT $IPMI_LOG_PARA_FORMAT "$LOG_ERR" "${PRESENT_OBJPATH[$i]}" "$LOG_EVENT_DATA" $LOG_DEASSERT_FLAG $LOG_GENID_FLAG
         fi
     done
     sleep 1
diff --git a/meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-sysinit.sh b/meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-sysinit.sh
index 8b660c2..67636c1 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-sysinit.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-sysinit.sh
@@ -14,7 +14,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
+# shellcheck source=meta-quanta/meta-gbs/recipes-gbs/gbs-sysinit/files/gbs-gpio-common.sh
 source /usr/libexec/gbs-gpio-common.sh
 
 WD1RCR_ADDR=0xf080103c
@@ -44,36 +44,36 @@
 }
 
 get_board_rev_id() {
-    echo $(get_gpio_value 'BMC_BRD_REV_ID7')\
-    $(get_gpio_value 'BMC_BRD_REV_ID6')\
-    $(get_gpio_value 'BMC_BRD_REV_ID5')\
-    $(get_gpio_value 'BMC_BRD_REV_ID4')\
-    $(get_gpio_value 'BMC_BRD_REV_ID3')\
-    $(get_gpio_value 'BMC_BRD_REV_ID2')\
-    $(get_gpio_value 'BMC_BRD_REV_ID1')\
-    $(get_gpio_value 'BMC_BRD_REV_ID0')\
+    echo "$(get_gpio_value 'BMC_BRD_REV_ID7')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID6')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID5')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID4')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID3')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID2')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID1')"\
+    "$(get_gpio_value 'BMC_BRD_REV_ID0')"\
     | sed 's/ //g' > ~/board_rev_id.txt
 }
 
 get_board_sku_id() {
-    echo $(get_gpio_value 'BMC_BRD_SKU_ID3')\
-    $(get_gpio_value 'BMC_BRD_SKU_ID2')\
-    $(get_gpio_value 'BMC_BRD_SKU_ID1')\
-    $(get_gpio_value 'BMC_BRD_SKU_ID0')\
+    echo "$(get_gpio_value 'BMC_BRD_SKU_ID3')"\
+    "$(get_gpio_value 'BMC_BRD_SKU_ID2')"\
+    "$(get_gpio_value 'BMC_BRD_SKU_ID1')"\
+    "$(get_gpio_value 'BMC_BRD_SKU_ID0')"\
     | sed 's/ //g' > ~/board_sku_id.txt
 }
 
 get_hsbp_board_rev_id() {
-    echo $(get_gpio_value 'HSBP_BRD_REV_ID3')\
-    $(get_gpio_value 'HSBP_BRD_REV_ID2')\
-    $(get_gpio_value 'HSBP_BRD_REV_ID1')\
-    $(get_gpio_value 'HSBP_BRD_REV_ID0')\
+    echo "$(get_gpio_value 'HSBP_BRD_REV_ID3')"\
+    "$(get_gpio_value 'HSBP_BRD_REV_ID2')"\
+    "$(get_gpio_value 'HSBP_BRD_REV_ID1')"\
+    "$(get_gpio_value 'HSBP_BRD_REV_ID0')"\
     | sed 's/ //g' > ~/hsbp_board_rev_id.txt
 }
 
 get_fan_board_rev_id() {
-    echo $(get_gpio_value 'FAN_BRD_REV_ID1')\
-    $(get_gpio_value 'FAN_BRD_REV_ID0')\
+    echo "$(get_gpio_value 'FAN_BRD_REV_ID1')"\
+    "$(get_gpio_value 'FAN_BRD_REV_ID0')"\
     | sed 's/ //g' > ~/fan_board_rev_id.txt
 }
 
@@ -100,10 +100,8 @@
   sku1_val=$(get_gpio_value 'BMC_BRD_SKU_ID1')
   if (( sku1_val == 1 )); then
     echo "GBS SKU!"
-    BOARD_SKU="GBS"
   else
     echo "Other SKU!"
-    BOARD_SKU="TBD"
   fi
 }
 
@@ -134,11 +132,9 @@
 # the node of FIU is spi for kernel 5.10, but
 # for less than or equal kernel 5.4, the node
 # is fiu
-shopt -s nullglob
-for fiu in "$KERNEL_SYSFS_FIU"/*.fiu; do
+if ls "$KERNEL_SYSFS_FIU"/*.fiu 1> /dev/null 2>&1; then
   KERNEL_FIU_ID="c0000000.fiu"
-  break
-done
+fi
 
 bind_host_mtd() {
   set_gpio_direction 'SPI_SW_SELECT' high
@@ -162,7 +158,7 @@
   m=$(grep -xl "$1" /sys/class/mtd/*/name)
   m=${m%/name}
   m=${m##*/}
-  echo $m
+  echo "$m"
 }
 
 verify_host_bios() {
@@ -176,7 +172,7 @@
   [[ -z "${pnor_mtd}" ]] && { echo "Failed to find host MTD  partition!"; return 1; }
 
   # Test timing by computing SHA256SUM.
-  sha256sum /dev/${pnor_mtd}ro
+  sha256sum "/dev/${pnor_mtd}ro"
 
   echo "BIOS verification complete!"
   unbind_host_mtd
@@ -186,12 +182,12 @@
   pe_fruid=3
   for i in {1..2};
   do
-     mapper wait ${PE_PRESENT_OBJPATH[$(($i-1))]}
-     pe_prsnt_n="$(busctl get-property $SERVICE_NAME ${PE_PRESENT_OBJPATH[$(($i-1))]} \
+     mapper wait "${PE_PRESENT_OBJPATH[$((i-1))]}"
+     pe_prsnt_n="$(busctl get-property $SERVICE_NAME "${PE_PRESENT_OBJPATH[$((i-1))]}" \
                   $INTERFACE_NAME Present)"
 
      if [[ ${pe_prsnt_n} == "b false" ]]; then
-         pe_fruid=$(($pe_fruid+1))
+         pe_fruid=$((pe_fruid+1))
          continue
      fi
 
@@ -199,6 +195,7 @@
      # i2c-0 -> i2c mux (addr: 0x71) -> PE0/PE1
      # PE0: channel 0
      # PE1: channel 1
+     # shellcheck disable=SC2010
      pe_fru_bus="$(ls -al /sys/bus/i2c/drivers/pca954x/0-0071/ | grep channel \
                    | awk -F "/" '{print $(NF)}' | awk -F "-" '{print $2}' | sed -n "${i}p")"
 
@@ -206,17 +203,16 @@
      # EEPROM part number) and perform a phosphor-read-eeprom
      for ((j=0; j < ${#pe_eeprom_addr[@]}; j++));
      do
-        i2cget -f -y $pe_fru_bus "0x${pe_eeprom_addr[$j]}" 0x01 > /dev/null 2>&1
-        if [ $? -eq 0 ]; then
+        if i2cget -f -y "$pe_fru_bus" "0x${pe_eeprom_addr[$j]}" 0x01 > /dev/null 2>&1 ; then
           if [ ! -f "/sys/bus/i2c/devices/$pe_fru_bus-00${pe_eeprom_addr[$j]}/eeprom" ]; then
             echo 24c02 "0x${pe_eeprom_addr[$j]}" > "/sys/bus/i2c/devices/i2c-$pe_fru_bus/new_device"
           fi
           pe_fru_bus="/sys/bus/i2c/devices/$pe_fru_bus-00${pe_eeprom_addr[$j]}/eeprom"
-          phosphor-read-eeprom --eeprom $pe_fru_bus --fruid $pe_fruid
+          phosphor-read-eeprom --eeprom "$pe_fru_bus" --fruid $pe_fruid
           break
         fi
      done
-     pe_fruid=$(($pe_fruid+1))
+     pe_fruid=$((pe_fruid+1))
   done
 }
 
@@ -224,7 +220,7 @@
     res0="$(busctl get-property -j xyz.openbmc_project.State.Chassis \
         /xyz/openbmc_project/state/chassis0 xyz.openbmc_project.State.Chassis \
         CurrentPowerState | jq -r '.["data"]')"
-    echo $res0
+    echo "$res0"
 }
 
 clk_buf_bus_switch="11-0076"
@@ -277,6 +273,6 @@
 }
 
 # Exit without running main() if sourced
-return 0 2>/dev/null
-
-main "$@"
+if ! (return 0 2>/dev/null) ; then
+    main "$@"
+fi
diff --git a/meta-quanta/meta-gbs/recipes-gbs/hotswap-power-cycle/files/tray_powercycle.sh b/meta-quanta/meta-gbs/recipes-gbs/hotswap-power-cycle/files/tray_powercycle.sh
index e22dd20..14136b7 100644
--- a/meta-quanta/meta-gbs/recipes-gbs/hotswap-power-cycle/files/tray_powercycle.sh
+++ b/meta-quanta/meta-gbs/recipes-gbs/hotswap-power-cycle/files/tray_powercycle.sh
@@ -27,12 +27,12 @@
 main() {
   # Stop phosphor-hwmon so that ADM1272 powercycle doesn't happen
   # in the middle of an i2c transaction and stuck the bus low
-  stop_phosphor_hwmon
+  stop_phosphor_hwmon "$@"
 
   gpioset gpiochip6 26=1
 }
 
 # Exit without running main() if sourced
-return 0 2>/dev/null
-
-main "$@"
+if ! (return 0 2>/dev/null) ; then
+    main "$@"
+fi
diff --git a/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-check-host-state.sh b/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-check-host-state.sh
index 1bff18d..97f9cfe 100644
--- a/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-check-host-state.sh
+++ b/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-check-host-state.sh
@@ -5,8 +5,8 @@
 dbus-monitor --system type='signal',interface='org.freedesktop.DBus.Properties',\
 member='PropertiesChanged',arg0namespace='xyz.openbmc_project.State.Chassis' | \
 while read -r line; do
-  grep -q member <<< $line && continue
-  if grep -q $state <<< $line; then
+  grep -q member <<< "$line" && continue
+  if grep -q $state <<< "$line"; then
     echo "Setting failsafe assuming host is off" >&2
     systemctl start --no-block gbs-host-s5-set-failsafe
   fi
diff --git a/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-set-failsafe.sh b/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-set-failsafe.sh
index bcd1d2c..8d6f774 100644
--- a/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-set-failsafe.sh
+++ b/meta-quanta/meta-gbs/recipes-google/acpi-power-state/acpi-power-state-daemon/gbs-set-failsafe.sh
@@ -22,10 +22,10 @@
   exit 1
 fi
 
-zone_num="$(busctl tree xyz.openbmc_project.State.FanCtrl | grep zone | wc -l)"
+zone_num="$(busctl tree xyz.openbmc_project.State.FanCtrl | grep -c zone)"
 result=0
 
-for (( i = 0; i < ${zone_num}; i++ )); do
+for (( i = 0; i < zone_num; i++ )); do
   retries=4
   busctl_error=-1
 
@@ -39,7 +39,7 @@
       sleep 1
     fi
 
-    let retries-=1
+    (( retries-=1 )) || true
   done
 
   if (( busctl_error != 0 )); then
diff --git a/meta-quanta/meta-gbs/recipes-phosphor/fans/phosphor-pid-control/fan-table-init.sh b/meta-quanta/meta-gbs/recipes-phosphor/fans/phosphor-pid-control/fan-table-init.sh
index 5ceac7e..427c98e 100644
--- a/meta-quanta/meta-gbs/recipes-phosphor/fans/phosphor-pid-control/fan-table-init.sh
+++ b/meta-quanta/meta-gbs/recipes-phosphor/fans/phosphor-pid-control/fan-table-init.sh
@@ -12,29 +12,29 @@
 mapper wait /xyz/openbmc_project/sensors/fan_tach/fb_fan2
 
 # generate fan table writePath
-Fan_0_To_4_Hwmon="$(ls /sys/devices/platform/ahb/ahb\:*/*pwm-fan-controller/hwmon/)"
+Fan_0_To_4_Hwmon="$(ls /sys/devices/platform/ahb/ahb:*/*pwm-fan-controller/hwmon/)"
 
 if [[ "$Fan_0_To_4_Hwmon" != "" ]]; then
-    sed -i "s/@Fan_0_To_4_Hwmon@/$Fan_0_To_4_Hwmon/g" $TEMP_FILE
+    sed -i "s/@Fan_0_To_4_Hwmon@/$Fan_0_To_4_Hwmon/g" "$TEMP_FILE"
 fi
 
 presentGpio=()
 presentState=()
 gpioPath="/sys/class/gpio/gpio"
 if [[ -f "/etc/nvme/nvme_config.json" ]]; then
-    presentGpio=($(cat /etc/nvme/nvme_config.json | grep NVMeDrivePresentPin \
+    # shellcheck disable=SC2207
+    presentGpio=($(grep NVMeDrivePresentPin /etc/nvme/nvme_config.json \
                    | awk '{print $2}' | cut -d "," -f 0))
 fi
 
 nvmePath="/xyz/openbmc_project/sensors/temperature/nvme"
-nvmeInventoryPath="/xyz/openbmc_project/inventory/system/chassis/motherboard/nvme"
 # Get and Set WCTEMP
 for ((i = 0; i < 16; i++)); do
     name="@WCTemp$(printf "%02d" $i)@"
     wcTemp=72000
 
     if [[ -d "${gpioPath}${presentGpio[i]}" ]] &&
-       [[ "$(cat ${gpioPath}${presentGpio[i]}/value)" == "0" ]]; then
+       [[ "$(cat "${gpioPath}${presentGpio[i]}/value")" == "0" ]]; then
         presentState[i]="true"
     else
         presentState[i]="false"
diff --git a/meta-quanta/meta-gbs/recipes-phosphor/sensors/phosphor-nvme/nvme_json_rewrite.sh b/meta-quanta/meta-gbs/recipes-phosphor/sensors/phosphor-nvme/nvme_json_rewrite.sh
index c8e328a..323be60 100644
--- a/meta-quanta/meta-gbs/recipes-phosphor/sensors/phosphor-nvme/nvme_json_rewrite.sh
+++ b/meta-quanta/meta-gbs/recipes-phosphor/sensors/phosphor-nvme/nvme_json_rewrite.sh
@@ -4,7 +4,7 @@
 
 export_gpio() {
   if [ ! -d "/sys/class/gpio/gpio$1" ]; then
-    echo $1 >/sys/class/gpio/export
+    echo "$1" >/sys/class/gpio/export
   fi
 }
 
@@ -18,8 +18,7 @@
     presentPinBase="$(cat /sys/bus/i2c/drivers/pca953x/1-0024/gpio/gpiochip*/base)"
     for i in {0..15};
     do
-        let presentPinBase[$i]=presentPinBase+$i
-        export_gpio ${presentPinBase[$i]}
+        export_gpio $(( presentPinBase + i ))
     done
 else
     echo "Can't find present gpio expander (addr: 0x24) !!"
@@ -29,8 +28,7 @@
     PwrGoodPinBase="$(cat /sys/bus/i2c/drivers/pca953x/1-0021/gpio/gpiochip*/base)"
     for i in {0..15};
     do
-        let PwrGoodPinBase[$i]=PwrGoodPinBase+$i
-        export_gpio ${PwrGoodPinBase[$i]}
+        export_gpio $(( PwrGoodPinBase + i ))
     done
 else
     echo "Can't find powergood gpio expander (addr: 0x21) !!"
@@ -46,8 +44,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_0_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_0_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_0_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[3]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[3]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 3)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 3))
         },
         {
             "NVMeDriveIndex": 1,
@@ -56,8 +54,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_1_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_1_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_1_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[2]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[2]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 2)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 2))
         },
         {
             "NVMeDriveIndex": 2,
@@ -66,8 +64,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_2_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_2_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_2_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[1]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[1]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 1)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 1))
         },
         {
             "NVMeDriveIndex": 3,
@@ -76,8 +74,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_3_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_3_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_3_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[0]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[0]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 0)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 0))
         },
         {
             "NVMeDriveIndex": 4,
@@ -86,8 +84,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_4_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_4_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_4_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[7]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[7]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 7)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 7))
         },
         {
             "NVMeDriveIndex": 5,
@@ -96,8 +94,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_5_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_5_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_5_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[6]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[6]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 6)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 6))
         },
         {
             "NVMeDriveIndex": 6,
@@ -106,8 +104,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_6_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_6_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_6_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[5]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[5]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 5)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 5))
         },
         {
             "NVMeDriveIndex": 7,
@@ -116,8 +114,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_7_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_7_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_7_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[4]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[4]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 4)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 4))
         },
         {
             "NVMeDriveIndex": 8,
@@ -126,8 +124,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_8_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_8_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_8_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[11]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[11]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 11)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 11))
         },
         {
             "NVMeDriveIndex": 9,
@@ -136,8 +134,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_9_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_9_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_9_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[10]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[10]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 10)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 10))
         },
         {
             "NVMeDriveIndex": 10,
@@ -146,8 +144,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_10_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_10_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_10_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[9]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[9]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 9)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 9))
         },
         {
             "NVMeDriveIndex": 11,
@@ -156,8 +154,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_11_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_11_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_11_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[8]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[8]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 8)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 8))
         },
         {
             "NVMeDriveIndex": 12,
@@ -166,8 +164,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_12_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_12_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_12_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[15]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[15]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 15)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 15))
         },
         {
             "NVMeDriveIndex": 13,
@@ -176,8 +174,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_13_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_13_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_13_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[14]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[14]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 14)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 14))
         },
         {
             "NVMeDriveIndex": 14,
@@ -186,8 +184,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_14_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_14_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_14_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[13]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[13]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 13)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 13))
         },
         {
             "NVMeDriveIndex": 15,
@@ -196,8 +194,8 @@
             "NVMeDriveLocateLEDGroupPath": "/xyz/openbmc_project/led/groups/led_u2_15_locate",
             "NVMeDriveLocateLEDControllerBusName": "xyz.openbmc_project.LED.Controller.led_u2_15_locate",
             "NVMeDriveLocateLEDControllerPath": "/xyz/openbmc_project/led/physical/led_u2_15_locate",
-            "NVMeDrivePresentPin": ${presentPinBase[12]},
-            "NVMeDrivePwrGoodPin": ${PwrGoodPinBase[12]}
+            "NVMeDrivePresentPin": $(( presentPinBase + 12)),
+            "NVMeDrivePwrGoodPin": $(( PwrGoodPinBase + 12))
         }
     ],
     "threshold": [
diff --git a/meta-quanta/meta-gsj/recipes-gsj/detect-fan-fail/files/detect-fan-fail.sh b/meta-quanta/meta-gsj/recipes-gsj/detect-fan-fail/files/detect-fan-fail.sh
index 80f1f69..20cdd6d 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/detect-fan-fail/files/detect-fan-fail.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/detect-fan-fail/files/detect-fan-fail.sh
@@ -3,14 +3,14 @@
 # get fan state by d-bus command
 function get_fan_state() {
     get_property_path='xyz.openbmc_project.Sensor.Threshold.Critical CriticalAlarmLow'
-    fan_state="$(busctl get-property $1 $2 $get_property_path | awk '{print $2}')"
+    fan_state="$(busctl get-property "$1" "$2" "$get_property_path" | awk '{print $2}')"
     echo "$fan_state"
 }
 
 # set fan pwm by d-bus command
 function set_fan_value() {
     set_property_path='xyz.openbmc_project.Control.FanPwm'
-    busctl set-property $1 $2 $set_property_path Target t 255
+    busctl set-property "$1" "$2" $set_property_path Target t 255
 }
 
 fan_tach_path=( '/xyz/openbmc_project/sensors/fan_tach/Fan0_0_RPM'
@@ -24,10 +24,10 @@
 check_fail_flag=0
 current_fan_state=()
 while true; do
-    hwmon_path="$(mapper get-service ${fan_tach_path[0]})"
-    for i in ${!fan_tach_path[@]};
+    hwmon_path="$(mapper get-service "${fan_tach_path[0]}")"
+    for i in "${!fan_tach_path[@]}";
     do
-        current_fan_state[$i%2]=$(get_fan_state $hwmon_path ${fan_tach_path[$i]})
+        current_fan_state[i%2]=$(get_fan_state "$hwmon_path" "${fan_tach_path[$i]}")
 
         #Compare state of dual rotors with CriticalAlarmLow to check if fan fail
         if [ ${#current_fan_state[@]} -eq 2 ];then
@@ -35,10 +35,10 @@
             [ "${current_fan_state[1]}" == "true" ] ;then
                 if [ $check_fail_flag -eq 0 ];then
                     systemctl stop phosphor-pid-control
-                    for j in ${!fan_tach_path[@]};
+                    for j in "${!fan_tach_path[@]}";
                     do
                         #If fan fail is detect, set other fan rpm to pwm 255.
-                        set_fan_value $hwmon_path ${fan_tach_path[$j]}
+                        set_fan_value "$hwmon_path" "${fan_tach_path[$j]}"
                         check_fail_flag=1
                     done
                 fi
@@ -49,7 +49,7 @@
         fi
 
         #fans are going to normal.
-        if [ $i -eq $((${#fan_tach_path[@]}-1)) ] && [ $check_fail_flag -eq 1 ]; then
+        if [ "$i" -eq $((${#fan_tach_path[@]}-1)) ] && [ $check_fail_flag -eq 1 ]; then
            check_fail_flag=0
            systemctl restart phosphor-pid-control
         fi
diff --git a/meta-quanta/meta-gsj/recipes-gsj/gsj-hotswap-change-setting/files/gsj-hotswap-change-setting.sh b/meta-quanta/meta-gsj/recipes-gsj/gsj-hotswap-change-setting/files/gsj-hotswap-change-setting.sh
index bed745d..118fe6c 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/gsj-hotswap-change-setting/files/gsj-hotswap-change-setting.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/gsj-hotswap-change-setting/files/gsj-hotswap-change-setting.sh
@@ -17,7 +17,7 @@
 function get_hotswap_value()
 {
     #get the value of reg "0xd9", return value should be "0x08"
-    echo "$(i2cget -f -y $I2C_BUS $CHIP_ADDR 0xd9)"
+    i2cget -f -y $I2C_BUS $CHIP_ADDR 0xd9
 }
 
 function export_gpio()
@@ -32,7 +32,7 @@
 
 function get_gpio_value()
 {
-    echo "$(cat $GPIO_BasePath/gpio$GPIO_ID/value)"
+    cat $GPIO_BasePath/gpio$GPIO_ID/value
 }
 
 function setting_hotswap()
@@ -64,4 +64,4 @@
     setting_hotswap
 else
     echo "gpio$GPIO_ID value is: $gpio_value, no need to set hotswap."
-fi
\ No newline at end of file
+fi
diff --git a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/init_once.sh b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/init_once.sh
index 08aa7a0..c6485a4 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/init_once.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/init_once.sh
@@ -1,58 +1,59 @@
 #!/bin/bash
 
+# shellcheck source=meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
 source /usr/libexec/nvme_powerctrl_library.sh
 
 function set_gpio() {
   #$1 gpio pin
-  echo $1 > /sys/class/gpio/export
+  echo "$1" > /sys/class/gpio/export
 }
 
 echo "Read Clock Gen Value is: $CLOCK_GEN_VALUE"
 
 ## Initial U2_PRESENT_N
-for i in ${!U2_PRESENT[@]};
+for i in "${!U2_PRESENT[@]}";
 do
-    set_gpio ${U2_PRESENT[$i]};
-    set_gpio_direction ${U2_PRESENT[$i]} 'in';
-    echo "Read $i SSD present: $(read_gpio_input ${U2_PRESENT[$i]})"
+    set_gpio "${U2_PRESENT[$i]}";
+    set_gpio_direction "${U2_PRESENT[$i]}" 'in';
+    echo "Read $i SSD present: $(read_gpio_input "${U2_PRESENT[$i]}")"
 done
 
 ## Initial POWER_U2_EN
-for i in ${!POWER_U2[@]};
+for i in "${!POWER_U2[@]}";
 do
-    set_gpio ${POWER_U2[$i]};
+    set_gpio "${POWER_U2[$i]}";
 done
 
 ## Initial PWRGD_U2
-for i in ${!PWRGD_U2[@]};
+for i in "${!PWRGD_U2[@]}";
 do
-    set_gpio ${PWRGD_U2[$i]};
-    set_gpio_direction ${PWRGD_U2[$i]} 'in';
-    echo "Read $i SSD Power Good: $(read_gpio_input ${PWRGD_U2[$i]})"
+    set_gpio "${PWRGD_U2[$i]}";
+    set_gpio_direction "${PWRGD_U2[$i]}" 'in';
+    echo "Read $i SSD Power Good: $(read_gpio_input "${PWRGD_U2[$i]}")"
 done
 
 ## Initial RST_BMC_U2
-for i in ${!RST_BMC_U2[@]};
+for i in "${!RST_BMC_U2[@]}";
 do
-    set_gpio ${RST_BMC_U2[$i]};
+    set_gpio "${RST_BMC_U2[$i]}";
 done
 
 ### Initial related Power by Present
 for i in {0..7};
 do
-    update_value=$(printf '%x\n' "$((0x01 <<$i))")
-    if [ $(read_gpio_input ${U2_PRESENT[$i]}) == $PLUGGED ];then
+    update_value=$(printf '%x\n' "$((0x01 << i))")
+    if [ "$(read_gpio_input "${U2_PRESENT[$i]}")" == $PLUGGED ];then
         CLOCK_GEN_VALUE=$(printf '0x%x\n' \
-        "$(($CLOCK_GEN_VALUE | 0x$update_value))")
+        "$((CLOCK_GEN_VALUE | 0x$update_value))")
     else
         set_gpio_direction "${RST_BMC_U2[$i]}" "low"
         set_gpio_direction "${POWER_U2[$i]}" "low"
 
         CLOCK_GEN_VALUE=$(printf '0x%x\n' \
-        "$(($CLOCK_GEN_VALUE & ~0x$update_value))")
+        "$((CLOCK_GEN_VALUE & ~0x$update_value))")
     fi
 done
-i2cset -y $I2C_BUS $CHIP_ADDR 0 $CLOCK_GEN_VALUE s
+i2cset -y $I2C_BUS $CHIP_ADDR 0 "$CLOCK_GEN_VALUE" s
 echo "Read Clock Gen Value again is: $CLOCK_GEN_VALUE"
 
 exit 0;
diff --git a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
index 3737aac..0ee436d 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
@@ -1,42 +1,44 @@
 #!/bin/bash
 
-U2_PRESENT=( 148 149 150 151 152 153 154 155 )
-POWER_U2=( 195 196 202 199 198 197 127 126 )
-PWRGD_U2=( 161 162 163 164 165 166 167 168 )
-RST_BMC_U2=( 72 73 74 75 76 77 78 79 )
-PLUGGED=0
-I2C_BUS=8
-CHIP_ADDR=0x68
+export U2_PRESENT=( 148 149 150 151 152 153 154 155 )
+export POWER_U2=( 195 196 202 199 198 197 127 126 )
+export PWRGD_U2=( 161 162 163 164 165 166 167 168 )
+export RST_BMC_U2=( 72 73 74 75 76 77 78 79 )
+export PLUGGED=0
+export I2C_BUS=8
+export CHIP_ADDR=0x68
+export CLOCK_GEN_VALUE=
+
 CLOCK_GEN_VALUE=$(i2cget -y $I2C_BUS $CHIP_ADDR 0 i 2|cut -f3 -d' ')
 
 function set_gpio_direction()
 {
     #$1 gpio pin, $2 'in','high','low'
-    echo $2 > /sys/class/gpio/gpio$1/direction
+    echo "$2" > "/sys/class/gpio/gpio$1/direction"
 }
 
 function read_gpio_input()
 {
     #$1 read input gpio pin
-    echo $(cat /sys/class/gpio/gpio$1/value)
+    cat "/sys/class/gpio/gpio$1/value"
 }
 
 function enable_nvme_power()
 {
     set_gpio_direction "${POWER_U2[$1]}" "high"
     sleep 0.04
-    check_powergood $1
+    check_powergood "$1"
 }
 
 function check_powergood()
 {
-    if [ $(read_gpio_input ${PWRGD_U2[$1]}) == 1 ];then
+    if [ "$(read_gpio_input "${PWRGD_U2[$1]}")" == 1 ];then
         sleep 0.005
-        update_clock_gen_chip_register $1 1
+        update_clock_gen_chip_register "$1" 1
         sleep 0.1
         set_gpio_direction "${RST_BMC_U2[$1]}" "high"
     else
-        disable_nvme_power $1
+        disable_nvme_power "$1"
     fi
 }
 
@@ -44,7 +46,7 @@
 {
     set_gpio_direction "${RST_BMC_U2[$1]}" "low"
     sleep 0.1
-    update_clock_gen_chip_register $1 0
+    update_clock_gen_chip_register "$1" 0
     sleep 0.005
     set_gpio_direction "${POWER_U2[$1]}" "low"
 }
@@ -52,12 +54,12 @@
 function update_clock_gen_chip_register(){
     #$1 nvme slot number, $2 enable/disable
     update_value=$(printf '%x\n' "$((0x01 <<$1))")
-    if [ $2 -eq 1 ];then
+    if [ "$2" -eq 1 ];then
         CLOCK_GEN_VALUE=$(printf '0x%x\n' \
-        "$(($CLOCK_GEN_VALUE | 0x$update_value))")
+        "$((CLOCK_GEN_VALUE | 0x$update_value))")
     else
         CLOCK_GEN_VALUE=$(printf '0x%x\n' \
-        "$(($CLOCK_GEN_VALUE & ~0x$update_value))")
+        "$((CLOCK_GEN_VALUE & ~0x$update_value))")
     fi
-    i2cset -y $I2C_BUS $CHIP_ADDR 0 $CLOCK_GEN_VALUE s
+    i2cset -y $I2C_BUS $CHIP_ADDR 0 "$CLOCK_GEN_VALUE" s
 }
diff --git a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powermanager.sh b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powermanager.sh
index 753c6c4..d6d9aa6 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powermanager.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powermanager.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
 
+# shellcheck source=meta-quanta/meta-gsj/recipes-gsj/quanta-nvme-powerctrl/files/nvme_powerctrl_library.sh
 source /usr/libexec/nvme_powerctrl_library.sh
 U2_PRESENT_STATUS=( 1 1 1 1 1 1 1 1 )
 
@@ -9,14 +10,14 @@
     sleep 0.2
     set_gpio_direction "${POWER_U2[$1]}" "high"
     sleep 0.2
-    check_powergood $1
+    check_powergood "$1"
 }
 
 
 ##Initial U2 present status
 for i in {0..7};
 do
-    U2_PRESENT_STATUS[$i]=$(read_gpio_input ${U2_PRESENT[$i]})
+    U2_PRESENT_STATUS[i]=$(read_gpio_input "${U2_PRESENT[$i]}")
 done
 
 ## Loop while
@@ -26,21 +27,21 @@
   do
     ## 1 second scan all loop
     sleep 0.125
-    read_present=$(read_gpio_input ${U2_PRESENT[$i]})
+    read_present=$(read_gpio_input "${U2_PRESENT[$i]}")
     if [ "$read_present" != "${U2_PRESENT_STATUS[$i]}" ];then
-        U2_PRESENT_STATUS[$i]="$read_present"
+        U2_PRESENT_STATUS[i]="$read_present"
         if [ "$read_present" == $PLUGGED ];then
             echo "NVME $i Enable Power"
-            enable_nvme_power $i
+            enable_nvme_power "$i"
         else
             echo "NVME $i Disable Power"
-            disable_nvme_power $i
+            disable_nvme_power "$i"
         fi
     else
         if [ "${U2_PRESENT_STATUS[$i]}" == $PLUGGED ] &&
-           [ $(read_gpio_input ${PWRGD_U2[$i]}) == 0 ];then
+           [ "$(read_gpio_input "${PWRGD_U2[$i]}")" == 0 ];then
             echo "NVME $i Recovery Power"
-            recovery_power $i
+            recovery_power "$i"
         fi
     fi
   done
diff --git a/meta-quanta/meta-gsj/recipes-gsj/usb-network/files/usb_network.sh b/meta-quanta/meta-gsj/recipes-gsj/usb-network/files/usb_network.sh
index 45fa888..1a27d90 100644
--- a/meta-quanta/meta-gsj/recipes-gsj/usb-network/files/usb_network.sh
+++ b/meta-quanta/meta-gsj/recipes-gsj/usb-network/files/usb_network.sh
@@ -1,26 +1,26 @@
 #!/bin/bash
 
-cd /sys/kernel/config/usb_gadget
+cd /sys/kernel/config/usb_gadget || exit
 
 if [ ! -f "g1" ]; then
     mkdir g1
-    cd g1
+    cd g1 || exit
 
     echo 0x1d6b > idVendor  # Linux foundation
     echo 0x0104 > idProduct # Multifunction composite gadget
     mkdir -p strings/0x409
     echo "Linux" > strings/0x409/manufacturer
     echo "Ethernet/RNDIS gadget" > strings/0x409/product
-    
+
     mkdir -p configs/c.1
     echo 100 > configs/c.1/MaxPower
     mkdir -p configs/c.1/strings/0x409
     echo "RNDIS" > configs/c.1/strings/0x409/configuration
-    
-    mkdir -p functions/rndis.usb0 
-    
+
+    mkdir -p functions/rndis.usb0
+
     ln -s functions/rndis.usb0 configs/c.1
-    
+
     echo f0839000.udc > UDC
 
 fi
diff --git a/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-control.sh b/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-control.sh
index 3c84ce4..afad9db 100644
--- a/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-control.sh
+++ b/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-control.sh
@@ -10,29 +10,29 @@
 for i in {0..7}
 do
   gpioNum=${NVME_GPIO_NUM[$i]}
-  NVME[$i]=$(cat /sys/class/gpio/gpio$gpioNum/value)
+  NVME[i]=$(cat "/sys/class/gpio/gpio$gpioNum/value")
 done
 
 # distinguish between 8-ssd and 2-ssd sku
 for i in {2..7}
 do
-  if [ ${NVME[$i]} -eq 0 ]; then
+  if [ "${NVME[$i]}" -eq 0 ]; then
     TYPE=0
   fi
 done
 if [ $TYPE -eq -1 ]; then
   for i in {0..1}
   do
-    if [ ${NVME[$i]} -eq 0 ]; then
+    if [ "${NVME[$i]}" -eq 0 ]; then
       TYPE=1
     fi
   done
 fi
 
 if [ $TYPE -eq 1 ]; then
-  cp ${FAN_TABLE[1]} $FAN_TABLE_PATH
+  cp "${FAN_TABLE[1]}" $FAN_TABLE_PATH
 else
-  cp ${FAN_TABLE[0]} $FAN_TABLE_PATH
+  cp "${FAN_TABLE[0]}" $FAN_TABLE_PATH
 fi
 
 # start pid control
diff --git a/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-default-speed.sh b/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-default-speed.sh
index 2cd3106..f119432 100644
--- a/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-default-speed.sh
+++ b/meta-quanta/meta-gsj/recipes-phosphor/fans/phosphor-pid-control/fan-default-speed.sh
@@ -1,4 +1,4 @@
-#!bin/bash
+#!/bin/bash
 
 echo 230 > /sys/class/hwmon/*/pwm1
 echo 230 > /sys/class/hwmon/*/pwm2
diff --git a/meta-quanta/meta-olympus-nuvoton/recipes-olympus-nuvoton/power/first-boot-set-psu/first-boot-set-psu.sh b/meta-quanta/meta-olympus-nuvoton/recipes-olympus-nuvoton/power/first-boot-set-psu/first-boot-set-psu.sh
index 04b4476..caceb5f 100644
--- a/meta-quanta/meta-olympus-nuvoton/recipes-olympus-nuvoton/power/first-boot-set-psu/first-boot-set-psu.sh
+++ b/meta-quanta/meta-olympus-nuvoton/recipes-olympus-nuvoton/power/first-boot-set-psu/first-boot-set-psu.sh
@@ -2,19 +2,19 @@
 
 string=''
 pmbus_read() {
-    data=$(i2cget -f -y $1 $2 $3 i $4)
+    data=$(i2cget -f -y "$1" "$2" "$3" i "$4")
 
     if [[ -z "$data" ]]; then
         echo "i2c$1 device $2 command $3 error" >&2
         exit 1
     fi
 
-	arry=$(echo ${data} | sed -e "s/$4\: //" | sed -e "s/\0x00//g" | sed -e "s/\0xff//g" | sed -e "s/\0x7f//g" | sed -e "s/\0x0f//g" | sed -e "s/\0x14//g")
+	arry=$(echo "${data}" | sed -e "s/$4\: //" | sed -e "s/\0x00//g" | sed -e "s/\0xff//g" | sed -e "s/\0x7f//g" | sed -e "s/\0x0f//g" | sed -e "s/\0x14//g")
 
     string=''
     for d in ${arry}
     do
-        hex=$(echo $d | sed -e "s/0\x//")
+        hex=${d/0x}
         string+=$(echo -e "\x${hex}");
     done
 }
@@ -28,9 +28,9 @@
           ${INVENTORY_SERVICE} \
           ${INVENTORY_OBJECT} \
           ${INVENTORY_PATH} \
-          Notify a{oa{sa{sv}}} 1 \
-          ${OBJECT_PATH} 1 $2 $3 \
-          $4 $5 $6
+          Notify "a{oa{sa{sv}}}" 1 \
+          "${OBJECT_PATH}" 1 "$2" "$3" \
+          "$4" "$5" "$6"
 }
 
 if [ $# -eq 0 ]; then
@@ -38,24 +38,22 @@
     exit 1
 fi
 
-input=$(echo $1 | tr "-" " ")
-arr=(${input// / });
+IFS=" " read -ra arr <<< "${1//- /}"
 
+pmbus_read "${arr[1]}" "${arr[2]}" 0x99 11
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "Manufacturer" "s" "$string"
 
-pmbus_read ${arr[1]} ${arr[2]} 0x99 11
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "Manufacturer" "s" $string
+pmbus_read "${arr[1]}" "${arr[2]}" 0x9a 11
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "Model" "s" "$string"
 
-pmbus_read ${arr[1]} ${arr[2]} 0x9a 11
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "Model" "s" $string
+pmbus_read "${arr[1]}" "${arr[2]}" 0xad 21
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "PartNumber" "s" "$string"
 
-pmbus_read ${arr[1]} ${arr[2]} 0xad 21
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "PartNumber" "s" $string
+pmbus_read "${arr[1]}" "${arr[2]}" 0x9e 18
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "SerialNumber" "s" "$string"
 
-pmbus_read ${arr[1]} ${arr[2]} 0x9e 18
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Asset" 1 "SerialNumber" "s" $string
-
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Cacheable" 1 "Cached" "b" "true"
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Decorator.Replaceable" 1 "FieldReplaceable" "b" "true"
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Item" 1 "Present" "b" "true"
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Item" 1 "PrettyName" "s" "powersupply${arr[0]}"
-update_inventory ${arr[0]} "xyz.openbmc_project.Inventory.Item.PowerSupply" 0
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Cacheable" 1 "Cached" "b" "true"
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Decorator.Replaceable" 1 "FieldReplaceable" "b" "true"
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Item" 1 "Present" "b" "true"
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Item" 1 "PrettyName" "s" "powersupply${arr[0]}"
+update_inventory "${arr[0]}" "xyz.openbmc_project.Inventory.Item.PowerSupply" 0
diff --git a/meta-quanta/meta-olympus-nuvoton/recipes-phosphor/fans/phosphor-pid-control/fan-full-speed.sh b/meta-quanta/meta-olympus-nuvoton/recipes-phosphor/fans/phosphor-pid-control/fan-full-speed.sh
index 9a0d8e2..243823a 100644
--- a/meta-quanta/meta-olympus-nuvoton/recipes-phosphor/fans/phosphor-pid-control/fan-full-speed.sh
+++ b/meta-quanta/meta-olympus-nuvoton/recipes-phosphor/fans/phosphor-pid-control/fan-full-speed.sh
@@ -1,3 +1,3 @@
-#!bin/bash
+#!/bin/bash
 
 echo 255 > /sys/class/hwmon/*/pwm1
diff --git a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/init_once.sh b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/init_once.sh
index 205ecaf..08b2880 100755
--- a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/init_once.sh
+++ b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/init_once.sh
@@ -7,26 +7,26 @@
     return;
   fi
 
-  echo $1 > /sys/class/gpio/export
-  echo 1 > /sys/class/gpio/gpio$1/active_low
-  echo $2 > /sys/class/gpio/gpio$1/direction
+  echo "$1" > /sys/class/gpio/export
+  echo 1 > "/sys/class/gpio/gpio$1/active_low"
+  echo "$2" > "/sys/class/gpio/gpio$1/direction"
 }
 
 GPIO_BASE=$(cat /sys/devices/platform/ahb/ahb:apb/1e780000.gpio/gpio/*/base)
 
 # FM_BMC_READY_N, GPIO Q4, active low
-set_gpio_active_low $((${GPIO_BASE} + 128 + 4)) high
+set_gpio_active_low $((GPIO_BASE + 128 + 4)) high
 
 # FM_BMC_SSB_SMI_LPC_N, GPIO Q6, active low
-set_gpio_active_low $((${GPIO_BASE} + 128 + 6)) high
+set_gpio_active_low $((GPIO_BASE + 128 + 6)) high
 
 # FM_BMC_SYS_THROTTLE_N, GPIO A3, active low
-set_gpio_active_low $((${GPIO_BASE} + 0 + 3)) high
+set_gpio_active_low $((GPIO_BASE + 0 + 3)) high
 
 # FM_BMC_SSB_SCI_LPC_N, GPIO E4, active low
-set_gpio_active_low $((${GPIO_BASE} + 32 + 4)) high
+set_gpio_active_low $((GPIO_BASE + 32 + 4)) high
 
 # FP_PWR_BTN_PASS_R_N, GPIO D3, active low
-set_gpio_active_low $((${GPIO_BASE} + 24 + 3)) high
+set_gpio_active_low $((GPIO_BASE + 24 + 3)) high
 
 exit 0;
diff --git a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweroff.sh b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweroff.sh
index 8e0dae3..5049f41 100755
--- a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweroff.sh
+++ b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweroff.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 GPIO_BASE=$(cat /sys/devices/platform/ahb/ahb:apb/1e780000.gpio/gpio/*/base)
-GPIO_NUM=$(($GPIO_BASE + 24 + 3))
+GPIO_NUM=$((GPIO_BASE + 24 + 3))
 
 echo 1 > /sys/class/gpio/gpio${GPIO_NUM}/value
 sleep 5
diff --git a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweron.sh b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweron.sh
index f925a33..2ae70de 100755
--- a/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweron.sh
+++ b/meta-quanta/meta-q71l/recipes-phosphor/quanta-powerctrl/files/poweron.sh
@@ -1,7 +1,7 @@
 #!/bin/bash
 
 GPIO_BASE=$(cat /sys/devices/platform/ahb/ahb:apb/1e780000.gpio/gpio/*/base)
-GPIO_NUM=$(($GPIO_BASE + 24 + 3))
+GPIO_NUM=$((GPIO_BASE + 24 + 3))
 
 echo 1 > /sys/class/gpio/gpio${GPIO_NUM}/value
 sleep 1