mavlink: enable 6 instead of 4 instance

src/modules/mavlink/mavlink_bridge_header.h

@@ -55,6 +55,12 @@
 #define MAVLINK_GET_CHANNEL_BUFFER mavlink_get_channel_buffer
 #define MAVLINK_GET_CHANNEL_STATUS mavlink_get_channel_status
 
+#if defined(__PX4_POSIX)
+#define MAVLINK_COMM_NUM_BUFFERS 6
+#define MAVLINK_COMM_4 static_cast<mavlink_channel_t>(4)
+#define MAVLINK_COMM_5 static_cast<mavlink_channel_t>(5)
+#endif
+
 #include <v2.0/mavlink_types.h>
 #include <unistd.h>
 

src/modules/mavlink/mavlink_command_sender.cpp

@@ -151,7 +151,7 @@ void MavlinkCommandSender::check_timeout(mavlink_channel_t channel)
 		// as some channels might be lagging behind and will end up putting the same command into the buffer.
 		bool dropped_command = false;
 
-		for (unsigned i = 0; i < MAX_MAVLINK_CHANNEL; ++i) {
+		for (unsigned i = 0; i < MAVLINK_COMM_NUM_BUFFERS; ++i) {
 			if (item->num_sent_per_channel[i] == -2) {
 				_commands.drop_current();
 				dropped_command = true;
@@ -176,7 +176,7 @@ void MavlinkCommandSender::check_timeout(mavlink_channel_t channel)
 		int8_t max_sent = 0;
 		int8_t min_sent = INT8_MAX;
 
-		for (unsigned i = 0; i < MAX_MAVLINK_CHANNEL; ++i) {
+		for (unsigned i = 0; i < MAVLINK_COMM_NUM_BUFFERS; ++i) {
 			if (item->num_sent_per_channel[i] > max_sent) {
 				max_sent = item->num_sent_per_channel[i];
 			}

src/modules/mavlink/mavlink_command_sender.h

@@ -102,14 +102,19 @@ private:
 	static MavlinkCommandSender *_instance;
 	static px4_sem_t _lock;
 
-	// There are MAVLINK_COMM_0 to MAVLINK_COMM_3, so it should be 4.
-	static const unsigned MAX_MAVLINK_CHANNEL = 4;
-
 	struct command_item_s {
 		mavlink_command_long_t command = {};
 		hrt_abstime timestamp_us = 0;
 		hrt_abstime last_time_sent_us = 0;
-		int8_t num_sent_per_channel[MAX_MAVLINK_CHANNEL] = {-1, -1, -1, -1}; // -1: channel did not request this command to be sent, -2: channel got an ack for this command
+		// -1: channel did not request this command to be sent, -2: channel got an ack for this command
+#if MAVLINK_COMM_NUM_BUFFERS == 4
+		int8_t num_sent_per_channel[MAVLINK_COMM_NUM_BUFFERS] = {-1, -1, -1, -1};
+#elif MAVLINK_COMM_NUM_BUFFERS == 6
+		int8_t num_sent_per_channel[MAVLINK_COMM_NUM_BUFFERS] = {-1, -1, -1, -1, -1, -1};
+#else
+#error Unknown number of MAVLINK_COMM_NUM_BUFFERS
+#endif
+
 	};
 
 	TimestampedList<command_item_s> _commands{3};

src/modules/mavlink/mavlink_log_handler.h

@@ -41,7 +41,7 @@
 #include <time.h>
 #include <stdio.h>
 #include <cstdbool>
-#include <v2.0/mavlink_types.h>
+#include "mavlink_bridge_header.h"
 #include <drivers/drv_hrt.h>
 
 class Mavlink;

src/modules/mavlink/mavlink_main.cpp

@@ -278,7 +278,7 @@ Mavlink::set_channel()
 #endif
 
 	default:
-		PX4_WARN("instance ID is out of range");
+		PX4_WARN("instance ID %d is out of range", _instance_id);
 		px4_task_exit(1);
 		break;
 	}

src/modules/mavlink/mavlink_main.h

@@ -540,7 +540,7 @@ private:
 
 	bool			_task_running{true};
 	static bool		_boot_complete;
-	static constexpr int	MAVLINK_MAX_INSTANCES{4};
+	static constexpr int	MAVLINK_MAX_INSTANCES{6};
 	static constexpr int	MAVLINK_MIN_INTERVAL{1500};
 	static constexpr int	MAVLINK_MAX_INTERVAL{10000};
 	static constexpr float	MAVLINK_MIN_MULTIPLIER{0.0005f};