ublox-config: Add poweroff feature

systemctl start ModemManager will start ublox-config first
systemctl stop ublox-config will stop ModemManager first

BugzID: 57325

recipes-connectivity/ublox-configuration/files/ublox-config.py

@@ -122,17 +122,36 @@ def apn_setup(ser):
     print("Full functionality mode")
     execute_and_check(ser, b'AT+CFUN=1\r')
 
+def poweroff(gpio):
+    print('poweroff')
+    if not os.path.exists(SERIAL_DEV):
+        print('serial interface is not available')
+        gpio.set_value(0)
+        return -1
+    ser = serial.Serial(SERIAL_DEV, 115200, timeout=0.5)
+    ser.write(b'AT+CPWROFF\r')
+    ser.close()
+
+    time.sleep(2)
+
+    gpio.set_value(0)
+
 def main():
     line = gpiod.find_line('GSM_SUP_EN')
     line.request(consumer='ublox-config', type=gpiod.LINE_REQ_DIR_OUT)
+
+    if len(sys.argv) == 2 and sys.argv[1] == 'stop':
+        return poweroff(line)
+
+    # Power on
     line.set_value(1)
 
-    rst = False
     # Wait on device
     while not os.path.exists(SERIAL_DEV):
         time.sleep(1)
     ser = serial.Serial(SERIAL_DEV, 115200, timeout=0.5)
 
+    rst = False
     if not os.path.exists(WWAN_DEV):
         print("Setting up bridge mode")
         execute_and_check(ser, b'AT+UBMCONF=2')

recipes-connectivity/ublox-configuration/files/ublox-config.service

@@ -4,8 +4,10 @@ Before=ModemManager.service
 [Service]
 Type=oneshot
 ExecStart=/usr/bin/ublox-config
+ExecStop=/usr/bin/ublox-config stop
+RemainAfterExit=yes
 
 [Install]
-WantedBy=ModemManager.service
+RequiredBy=ModemManager.service