Navio: GPIO driver command fix and update ifdefs

src/drivers/navio_gpio/navio_gpio.cpp

@@ -145,10 +145,10 @@ int navio_gpio_main(int argc, char *argv[])
 	}
 
 	if (!strcmp(argv[1], "start")) {
+		PX4_WARN("gpio should only be started directly for debugging");
 
 		if (gpio != nullptr && gpio->isMapped()) {
 			PX4_WARN("already mapped");
-			/* this is not an error */
 			return 0;
 		}
 
@@ -156,13 +156,14 @@ int navio_gpio_main(int argc, char *argv[])
 
 		if (gpio == nullptr) {
 			PX4_ERR("alloc failed");
-			return -1;
+			return 1;
 		}
 
 		int ret = gpio->start();
 
 		if (ret != 0) {
 			PX4_ERR("start failed");
+			return 1;
 		}
 
 		return 0;
@@ -170,12 +171,16 @@ int navio_gpio_main(int argc, char *argv[])
 
 	if (!strcmp(argv[1], "stop")) {
 
-		if (gpio == nullptr || gpio->isMapped()) {
-			PX4_WARN("not mapped");
-			/* this is not an error */
+		if (gpio == nullptr) {
+			PX4_WARN("gpio not started from navio_gpio");
 			return 0;
 		}
 
+		if (!gpio->isMapped()) {
+			PX4_WARN("not mapped");
+			return 1;
+		}
+
 		gpio->stop();
 
 		delete gpio;
@@ -185,7 +190,12 @@ int navio_gpio_main(int argc, char *argv[])
 	}
 
 	if (!strcmp(argv[1], "status")) {
-		if (gpio != nullptr && gpio->isMapped()) {
+		if (gpio == nullptr) {
+			PX4_WARN("gpio not started from navio_gpio");
+			return 0;
+		}
+
+		if (gpio->isMapped()) {
 			PX4_INFO("mapped");
 
 		} else {

src/drivers/navio_gpio/navio_gpio.h

@@ -86,13 +86,10 @@ namespace navio_gpio
 class Gpio
 {
 public:
-	Gpio() :
-		_isMapped(false)
-	{
-	}
+	Gpio()
+	{ }
 	~Gpio()
-	{
-	}
+	{ }
 
 	int start();
 	int stop();
@@ -102,7 +99,7 @@ public:
 	bool gpioread(uint32_t pinset);
 	void gpiowrite(uint32_t pinset, bool value);
 
-	bool isMapped() { return _isMapped; }
+	bool isMapped() { return _gpio_map != nullptr; }
 
 private:
 	void atomic_modify(uint32_t addr,
@@ -111,7 +108,6 @@ private:
 			   unsigned int value);
 
 	void *_gpio_map;
-	bool _isMapped;
 
 	SyncObj m_lock;
 };