AP_Motors: make pwm_type protected and add helpers

libraries/AP_Motors/AP_Motors_Class.cpp

@@ -208,6 +208,25 @@ void AP_Motors::set_limit_flag_pitch_roll_yaw(bool flag)
     limit.yaw = flag;
 }
 
+// returns true if the configured PWM type is digital and should have fixed endpoints
+bool AP_Motors::is_digital_pwm_type() const
+{
+    switch (_pwm_type) {
+        case PWM_TYPE_DSHOT150:
+        case PWM_TYPE_DSHOT300:
+        case PWM_TYPE_DSHOT600:
+        case PWM_TYPE_DSHOT1200:
+            return true;
+        case PWM_TYPE_NORMAL:
+        case PWM_TYPE_ONESHOT:
+        case PWM_TYPE_ONESHOT125:
+        case PWM_TYPE_BRUSHED:
+        case PWM_TYPE_PWM_RANGE:
+            break;
+    }
+    return false;
+}
+
 namespace AP {
     AP_Motors *motors()
     {

libraries/AP_Motors/AP_Motors_Class.h

@@ -219,16 +219,14 @@ public:
     // This function is overriden in motors_heli class.   Always true for multicopters.
     virtual bool init_targets_on_arming() const { return true; }
 
-    enum pwm_type { PWM_TYPE_NORMAL     = 0,
-                    PWM_TYPE_ONESHOT    = 1,
-                    PWM_TYPE_ONESHOT125 = 2,
-                    PWM_TYPE_BRUSHED    = 3,
-                    PWM_TYPE_DSHOT150   = 4,
-                    PWM_TYPE_DSHOT300   = 5,
-                    PWM_TYPE_DSHOT600   = 6,
-                    PWM_TYPE_DSHOT1200  = 7,
-                    PWM_TYPE_PWM_RANGE  = 8 };
-    pwm_type            get_pwm_type(void) const { return (pwm_type)_pwm_type.get(); }
+    // returns true if the configured PWM type is digital and should have fixed endpoints
+    bool is_digital_pwm_type() const;
+
+    // returns true is pwm type is brushed
+    bool is_brushed_pwm_type() const { return _pwm_type == PWM_TYPE_BRUSHED; }
+
+    // returns true is pwm type is normal
+    bool is_normal_pwm_type() const { return (_pwm_type == PWM_TYPE_NORMAL) || (_pwm_type == PWM_TYPE_PWM_RANGE); }
 
     MAV_TYPE get_frame_mav_type() const { return _mav_type; }
 
@@ -300,6 +298,16 @@ protected:
 
     MAV_TYPE _mav_type; // MAV_TYPE_GENERIC = 0;
 
+    enum pwm_type { PWM_TYPE_NORMAL     = 0,
+                    PWM_TYPE_ONESHOT    = 1,
+                    PWM_TYPE_ONESHOT125 = 2,
+                    PWM_TYPE_BRUSHED    = 3,
+                    PWM_TYPE_DSHOT150   = 4,
+                    PWM_TYPE_DSHOT300   = 5,
+                    PWM_TYPE_DSHOT600   = 6,
+                    PWM_TYPE_DSHOT1200  = 7,
+                    PWM_TYPE_PWM_RANGE  = 8 };
+
 private:
 
     bool _armed;             // 0 if disarmed, 1 if armed