rc_input: add RC_PORT_CONFIG param to configure RC port

The parameter will only be available if the board defines an 'RC' serial
port in SERIAL_PORTS (in default.cmake).

ROMFS/px4fmu_common/init.d/rcS

@@ -52,6 +52,7 @@ set PWM_MAX p:PWM_MAX
 set PWM_MIN p:PWM_MIN
 set PWM_OUT none
 set PWM_RATE p:PWM_RATE
+set RC_INPUT_ARGS ""
 set SDCARD_MIXERS_PATH /fs/microsd/etc/mixers
 set USE_IO no
 set VEHICLE_TYPE none
@@ -318,11 +319,6 @@ else
 		tune_control play -t 2
 	fi
 
-	if [ $IO_PRESENT = no -o $USE_IO = no ]
-	then
-		rc_input start
-	fi
-
 	#
 	# Sensors System (start before Commander so Preflight checks are properly run).
 	# Commander needs to be this early for in-air-restarts.
@@ -418,6 +414,12 @@ else
 	#
 	sh /etc/init.d/rc.serial
 
+	if [ $IO_PRESENT = no -o $USE_IO = no ]
+	then
+		# Must be started after the serial config is read
+		rc_input start $RC_INPUT_ARGS
+	fi
+
 	#
 	# Configure vehicle type specific parameters.
 	# Note: rc.vehicle_setup is the entry point for rc.interface,
@@ -546,6 +548,7 @@ unset PWM_MAX
 unset PWM_MIN
 unset PWM_OUT
 unset PWM_RATE
+unset RC_INPUT_ARGS
 unset SDCARD_MIXERS_PATH
 unset USE_IO
 unset VEHICLE_TYPE

Tools/serial/generate_config.py

@@ -108,6 +108,13 @@ serial_ports = {
         "default_baudrate": 0,
         },
 
+    # RC Port
+    "RC": {
+        "label": "Radio Controller",
+        "index": 300,
+        "default_baudrate": 0,
+        },
+
     }
 
 parser = argparse.ArgumentParser(description='Generate Serial params & startup script')
@@ -280,6 +287,15 @@ for serial_command in serial_commands:
     for i in range(num_instances):
         port_config = serial_command['port_config_param']
         port_param_name = port_config['name'].replace('${i}', str(i))
+
+        # check if a port dependency is specified
+        if 'depends_on_port' in port_config:
+            depends_on_port = port_config['depends_on_port']
+            if not any(p['tag'] == depends_on_port for p in serial_devices):
+                if verbose:
+                    print("Skipping {:} (missing dependent port)".format(port_param_name))
+                continue
+
         default_port = 0 # disabled
         if 'default' in port_config:
             if type(port_config['default']) == list:
@@ -299,7 +315,8 @@ for serial_command in serial_commands:
             'multi_instance': num_instances > 1,
             'port_param_name': port_param_name,
             'default_port': default_port,
-            'param_group': port_config['group']
+            'param_group': port_config['group'],
+            'description_extended': port_config.get('description_extended', '')
             })
 
 if verbose:

Tools/serial/serial_params.c.jinja

@@ -52,6 +52,8 @@ PARAM_DEFINE_INT32(SER_{{ serial_device.tag }}_BAUD, {{ serial_device.default_ba
  *
  * Configure on which serial port to run {{ command.label }}.
  *
+ * {{ command.description_extended | replace("\n", " ") }}
+ *
  * @value 0 Disabled
 {% for serial_device in serial_devices -%}
  * @value {{ serial_device.index }} {{ serial_device.label }}

src/drivers/rc_input/CMakeLists.txt

@@ -38,6 +38,8 @@ px4_add_module(
 	SRCS
 		RCInput.cpp
 		crsf_telemetry.cpp
+	MODULE_CONFIG
+		module.yaml
 	DEPENDS
 		rc
 	)

src/drivers/rc_input/module.yaml

@@ -0,0 +1,12 @@
+module_name: RC Input Driver
+serial_config:
+    - command: set RC_INPUT_ARGS "-d ${SERIAL_DEV}"
+      port_config_param:
+        name: RC_PORT_CONFIG
+        group: Serial
+        default: RC
+        depends_on_port: RC
+        description_extended: |
+            Setting this to 'Disabled' will use a board-specific default port
+            for RC input.
+

validation/module_schema.yaml

@@ -54,6 +54,15 @@ serial_config:
                               minlength: 1
                               schema:
                                   type: string
+                    depends_on_port:
+                        # Optional serial tag dependency (e.g. GPS1). If a board
+                        # does not specify this serial port, the parameter will
+                        # not be included in the build (i.e. it's not
+                        # configurable)
+                        type: string
+                    description_extended:
+                        # Optional extended description
+                        type: string
             label:
                 # Optional command label (e.g. used in the autostart script).
                 # If omitted, module_name is used.