AP_BattMonitor: Remove redundant state copy

Every backend stored a instance reference, which wasn't used in most locations
which is redundant given that the state already tracks the instance for us as
well.

libraries/AP_BattMonitor/AP_BattMonitor.cpp

@@ -180,25 +180,25 @@ AP_BattMonitor::init()
             case BattMonitor_TYPE_ANALOG_VOLTAGE_ONLY:
             case BattMonitor_TYPE_ANALOG_VOLTAGE_AND_CURRENT:
                 state[instance].instance = instance;
-                drivers[instance] = new AP_BattMonitor_Analog(*this, instance, state[instance]);
+                drivers[instance] = new AP_BattMonitor_Analog(*this, state[instance]);
                 _num_instances++;
                 break;
             case BattMonitor_TYPE_SOLO:
                 state[instance].instance = instance;
-                drivers[instance] = new AP_BattMonitor_SMBus_Solo(*this, instance, state[instance],
+                drivers[instance] = new AP_BattMonitor_SMBus_Solo(*this, state[instance],
                                                                  hal.i2c_mgr->get_device(AP_BATTMONITOR_SMBUS_BUS_INTERNAL, AP_BATTMONITOR_SMBUS_I2C_ADDR));
                 _num_instances++;
                 break;
             case BattMonitor_TYPE_MAXELL:
                 state[instance].instance = instance;
-                drivers[instance] = new AP_BattMonitor_SMBus_Maxell(*this, instance, state[instance],
+                drivers[instance] = new AP_BattMonitor_SMBus_Maxell(*this, state[instance],
                                                                  hal.i2c_mgr->get_device(AP_BATTMONITOR_SMBUS_BUS_EXTERNAL, AP_BATTMONITOR_SMBUS_I2C_ADDR));
                 _num_instances++;
                 break;
             case BattMonitor_TYPE_BEBOP:
 #if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_BEBOP || CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_DISCO
                 state[instance].instance = instance;
-                drivers[instance] = new AP_BattMonitor_Bebop(*this, instance, state[instance]);
+                drivers[instance] = new AP_BattMonitor_Bebop(*this, state[instance]);
                 _num_instances++;
 #endif
                 break;

libraries/AP_BattMonitor/AP_BattMonitor_Analog.cpp

@@ -7,11 +7,11 @@
 extern const AP_HAL::HAL& hal;
 
 /// Constructor
-AP_BattMonitor_Analog::AP_BattMonitor_Analog(AP_BattMonitor &mon, uint8_t instance, AP_BattMonitor::BattMonitor_State &mon_state) :
-    AP_BattMonitor_Backend(mon, instance, mon_state)
+AP_BattMonitor_Analog::AP_BattMonitor_Analog(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state) :
+    AP_BattMonitor_Backend(mon, mon_state)
 {
-    _volt_pin_analog_source = hal.analogin->channel(mon._volt_pin[instance]);
-    _curr_pin_analog_source = hal.analogin->channel(mon._curr_pin[instance]);
+    _volt_pin_analog_source = hal.analogin->channel(mon._volt_pin[_state.instance]);
+    _curr_pin_analog_source = hal.analogin->channel(mon._curr_pin[_state.instance]);
 
     // always healthy
     _state.healthy = true;

libraries/AP_BattMonitor/AP_BattMonitor_Analog.h

@@ -82,7 +82,7 @@ class AP_BattMonitor_Analog : public AP_BattMonitor_Backend
 public:
 
     /// Constructor
-    AP_BattMonitor_Analog(AP_BattMonitor &mon, uint8_t instance, AP_BattMonitor::BattMonitor_State &mon_state);
+    AP_BattMonitor_Analog(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state);
 
     /// Read the battery voltage and current.  Should be called at 10hz
     void read();

libraries/AP_BattMonitor/AP_BattMonitor_Backend.cpp

@@ -22,10 +22,9 @@
   base class constructor.
   This incorporates initialisation as well.
 */
-AP_BattMonitor_Backend::AP_BattMonitor_Backend(AP_BattMonitor &mon, uint8_t instance, AP_BattMonitor::BattMonitor_State &mon_state) :
+AP_BattMonitor_Backend::AP_BattMonitor_Backend(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state) :
         _mon(mon),
-        _state(mon_state),
-        _instance(instance)
+        _state(mon_state)
 {
 }
 
@@ -43,11 +42,11 @@ uint8_t AP_BattMonitor_Backend::capacity_remaining_pct() const
 /// set capacity for this instance
 void AP_BattMonitor_Backend::set_capacity(uint32_t capacity)
 {
-    _mon._pack_capacity[_instance] = capacity;
+    _mon._pack_capacity[_state.instance] = capacity;
 }
 
 /// get capacity for this instance
 int32_t AP_BattMonitor_Backend::get_capacity() const
 {
-    return _mon.pack_capacity_mah(_instance);
+    return _mon.pack_capacity_mah(_state.instance);
 }

libraries/AP_BattMonitor/AP_BattMonitor_Backend.h

@@ -22,7 +22,7 @@ class AP_BattMonitor_Backend
 {
 public:
     // constructor. This incorporates initialisation as well.
-    AP_BattMonitor_Backend(AP_BattMonitor &mon, uint8_t instance, AP_BattMonitor::BattMonitor_State &mon_state);
+    AP_BattMonitor_Backend(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state);
 
     // we declare a virtual destructor so that BattMonitor driver can
     // override with a custom destructor if need be
@@ -46,5 +46,4 @@ public:
 protected:
     AP_BattMonitor                      &_mon;      // reference to front-end
     AP_BattMonitor::BattMonitor_State   &_state;    // reference to this instances state (held in the front-end)
-    uint8_t                              _instance; // this instance
 };

libraries/AP_BattMonitor/AP_BattMonitor_Bebop.h

@@ -22,8 +22,8 @@ class AP_BattMonitor_Bebop :public AP_BattMonitor_Backend
 {
 public:
     // constructor. This incorporates initialisation as well.
-    AP_BattMonitor_Bebop(AP_BattMonitor &mon, uint8_t instance, AP_BattMonitor::BattMonitor_State &mon_state):
-        AP_BattMonitor_Backend(mon, instance, mon_state),
+    AP_BattMonitor_Bebop(AP_BattMonitor &mon, AP_BattMonitor::BattMonitor_State &mon_state):
+        AP_BattMonitor_Backend(mon, mon_state),
         _prev_vbat_raw(0.0f),
         _prev_vbat(0.0f),
         _battery_voltage_max(0.0f)

libraries/AP_BattMonitor/AP_BattMonitor_SMBus.h

@@ -16,7 +16,7 @@ class AP_BattMonitor_SMBus : public AP_BattMonitor_Backend
 public:
 
     /// Constructor
-    AP_BattMonitor_SMBus(AP_BattMonitor &mon, uint8_t instance,
+    AP_BattMonitor_SMBus(AP_BattMonitor &mon,
                     AP_BattMonitor::BattMonitor_State &mon_state,
                     AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev);
 

libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Maxell.cpp

@@ -36,10 +36,10 @@ uint8_t maxell_cell_ids[] = { 0x3f,  // cell 1
 */
 
 // Constructor
-AP_BattMonitor_SMBus_Maxell::AP_BattMonitor_SMBus_Maxell(AP_BattMonitor &mon, uint8_t instance,
+AP_BattMonitor_SMBus_Maxell::AP_BattMonitor_SMBus_Maxell(AP_BattMonitor &mon,
                                                    AP_BattMonitor::BattMonitor_State &mon_state,
                                                    AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev)
-    : AP_BattMonitor_SMBus(mon, instance, mon_state, std::move(dev))
+    : AP_BattMonitor_SMBus(mon, mon_state, std::move(dev))
 {
     _dev->register_periodic_callback(100000, FUNCTOR_BIND_MEMBER(&AP_BattMonitor_SMBus_Maxell::timer, void));
 }

libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Maxell.h

@@ -11,7 +11,7 @@ class AP_BattMonitor_SMBus_Maxell : public AP_BattMonitor_SMBus
 public:
 
     // Constructor
-    AP_BattMonitor_SMBus_Maxell(AP_BattMonitor &mon, uint8_t instance,
+    AP_BattMonitor_SMBus_Maxell(AP_BattMonitor &mon,
                              AP_BattMonitor::BattMonitor_State &mon_state,
                              AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev);
 

libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.cpp

@@ -29,10 +29,10 @@
  */
 
 // Constructor
-AP_BattMonitor_SMBus_Solo::AP_BattMonitor_SMBus_Solo(AP_BattMonitor &mon, uint8_t instance,
+AP_BattMonitor_SMBus_Solo::AP_BattMonitor_SMBus_Solo(AP_BattMonitor &mon,
                                                    AP_BattMonitor::BattMonitor_State &mon_state,
                                                    AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev)
-    : AP_BattMonitor_SMBus(mon, instance, mon_state, std::move(dev))
+    : AP_BattMonitor_SMBus(mon, mon_state, std::move(dev))
 {
     _pec_supported = true;
     _dev->register_periodic_callback(100000, FUNCTOR_BIND_MEMBER(&AP_BattMonitor_SMBus_Solo::timer, void));

libraries/AP_BattMonitor/AP_BattMonitor_SMBus_Solo.h

@@ -11,7 +11,7 @@ class AP_BattMonitor_SMBus_Solo : public AP_BattMonitor_SMBus
 public:
 
     // Constructor
-    AP_BattMonitor_SMBus_Solo(AP_BattMonitor &mon, uint8_t instance,
+    AP_BattMonitor_SMBus_Solo(AP_BattMonitor &mon,
                              AP_BattMonitor::BattMonitor_State &mon_state,
                              AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev);