AP_HAL_AVR: AnalogIn channels respect pins, obey NONE input, all common

* there's no need for separate APM1/APM2 classes, so that was eliminated
* single class only has special member for vcc. all others created by
  channel interface.

libraries/AP_HAL_AVR/AP_HAL_AVR.cpp

@@ -32,8 +32,7 @@ static EmptyUARTDriver  emptyUartDriver;
 
 static AVRI2CDriver     avrI2CDriver;
 static ArduinoSPIDriver arduinoSPIDriver;
-static APM1AnalogIn     apm1AnalogIn;
-static APM2AnalogIn     apm2AnalogIn;
+static AVRAnalogIn      analogIn;
 static AVREEPROMStorage avrEEPROMStorage;
 static APM1Dataflash    apm1Dataflash;
 static APM2Dataflash    apm2Dataflash;
@@ -52,7 +51,7 @@ const HAL_AVR AP_HAL_AVR_APM1(
         (UARTDriver*) &avrUart3Driver,
         &avrI2CDriver,
         &arduinoSPIDriver,
-        &apm1AnalogIn,
+        &analogIn,
         &avrEEPROMStorage,
         &apm1Dataflash,
         &consoleDriver,
@@ -68,7 +67,7 @@ const HAL_AVR AP_HAL_AVR_APM2(
         (UARTDriver*) &emptyUartDriver,
         &avrI2CDriver,
         &arduinoSPIDriver,
-        &apm2AnalogIn,
+        &analogIn,
         &avrEEPROMStorage,
         &apm2Dataflash,
         &consoleDriver,

libraries/AP_HAL_AVR/AP_HAL_AVR_Namespace.h

@@ -10,8 +10,6 @@ namespace AP_HAL_AVR {
     class ArduinoSPIDriver;
     class ADCSource;
     class AVRAnalogIn;
-    class APM1AnalogIn;
-    class APM2AnalogIn;
     class AVREEPROMStorage;
     class CommonDataflash;
     class APM1Dataflash;

libraries/AP_HAL_AVR/AnalogIn.h

@@ -5,11 +5,11 @@
 #include <AP_HAL.h>
 #include "AP_HAL_AVR_Namespace.h"
 
-#define AVR_ANALOG_PIN_VCC 255
-#define AVR_INPUT_MAX_CHANNELS 6
+#define AVR_INPUT_MAX_CHANNELS 12
 
 class AP_HAL_AVR::ADCSource : public AP_HAL::AnalogSource {
 public:
+    friend class AP_HAL_AVR::AVRAnalogIn;
     /* pin designates the ADC input number, or when == AVR_ANALOG_PIN_VCC,
      * board vcc */
     ADCSource(uint8_t pin, float prescale = 1.0);
@@ -29,6 +29,8 @@ public:
     /* read_average: called to calculate and clear the internal average.
      * implements read(). */
     float read_average();
+
+    int get_pin() { return _pin; };
 private:
     /* _sum_count and _sum are used from both an interrupt and normal thread */
     volatile uint8_t _sum_count;
@@ -40,47 +42,26 @@ private:
     const float _prescale;
 };
 
-
 /* AVRAnalogIn : a concrete class providing the implementations of the 
- * timer event */
-class AP_HAL_AVR::AVRAnalogIn {
+ * timer event and the AP_HAL::AnalogIn interface */
+class AP_HAL_AVR::AVRAnalogIn : public AP_HAL::AnalogIn {
 public:
     AVRAnalogIn();
+    void init(void* ap_hal_scheduler);
+    AP_HAL::AnalogSource* channel(int n);
+
 protected: 
+    static ADCSource* _find_or_create_channel(int num);
+    static ADCSource* _create_channel(int num);
     static void _register_channel(ADCSource*);
     static void _timer_event(uint32_t);
     static ADCSource* _channels[AVR_INPUT_MAX_CHANNELS];
     static int _num_channels;
     static int _active_channel;
     static int _channel_repeat_count;
+
+private:
+    ADCSource _vcc;
 };
 
-/* APM1AnalogIn and APM2AnalogIn match the implementations in the AVRAnalogIn
- * class with the AP_HAL::AnalogIn's channel interface. */
-class AP_HAL_AVR::APM1AnalogIn : public AP_HAL::AnalogIn,
-                                 public AP_HAL_AVR::AVRAnalogIn {
-public:
-    APM1AnalogIn();
-    void init(void* ap_hal_scheduler);
-    AP_HAL::AnalogSource* channel(int n);
-private:
-    ADCSource _bat_voltage;
-    ADCSource _bat_current;
-    ADCSource _vdd;
-};
-
-class AP_HAL_AVR::APM2AnalogIn : public AP_HAL::AnalogIn,
-                                 public AP_HAL_AVR::AVRAnalogIn {
-public:
-    APM2AnalogIn();
-    void init(void* ap_hal_scheduler);
-    AP_HAL::AnalogSource* channel(int n);
-private:
-    ADCSource _pitot;
-    ADCSource _bat_voltage;
-    ADCSource _bat_current;
-    ADCSource _rssi;
-    ADCSource _vdd;
-};
 #endif // __AP_HAL_AVR_ANALOG_IN_H__
-

libraries/AP_HAL_AVR/AnalogIn_ADC.cpp

@@ -27,7 +27,7 @@ float ADCSource::read_average() {
      * have a way to bubble control upwards at the moment. -pch */
     while( _sum_count == 0 );
 
-    /* Read and clear the */
+    /* Read and clear in a critical section */
     cli();
     sum = _sum;
     sum_count = _sum_count;
@@ -40,15 +40,16 @@ float ADCSource::read_average() {
 }
 
 void ADCSource::setup_read() {
-    if (_pin == AVR_ANALOG_PIN_VCC) {
+    if (_pin == ANALOG_INPUT_BOARD_VCC) {
         ADMUX = _BV(REFS0)|_BV(MUX4)|_BV(MUX3)|_BV(MUX2)|_BV(MUX1);
+    } else if (_pin == ANALOG_INPUT_NONE) {
+        /* noop */
     } else {
         ADCSRB = (ADCSRB & ~(1 << MUX5)) | (((_pin >> 3) & 0x01) << MUX5);
         ADMUX = _BV(REFS0) | (_pin & 0x07);
     }
 }
 
-
 /* new_sample is called from an interrupt. It always has access to
  *  _sum and _sum_count. Lock out the interrupts briefly with
  * cli/sei to read these variables from outside an interrupt. */

libraries/AP_HAL_AVR/AnalogIn_APM1.cpp

@@ -1,38 +0,0 @@
-
-#include <AP_HAL.h>
-#include "AnalogIn.h"
-using namespace AP_HAL_AVR;
-
-extern const AP_HAL::HAL& hal;
-
-APM1AnalogIn::APM1AnalogIn () :
-    _bat_voltage(ADCSource(0)),
-    _bat_current(ADCSource(1)),
-    _vdd(ADCSource(AVR_ANALOG_PIN_VCC)),
-    AVRAnalogIn()
-{ }
-
-void APM1AnalogIn::init(void* machtnichts) {
-    /* Register AVRAnalogIn::_timer_event with the scheduler. */
-    hal.scheduler->register_timer_process(_timer_event);
-    /* Register each private channel with AVRAnalogIn. */
-    _register_channel(&_bat_voltage);
-    _register_channel(&_bat_current);
-    _register_channel(&_vdd);
-}
-
-AP_HAL::AnalogSource* APM1AnalogIn::channel(int ch) {
-    switch(ch) {
-        case 0:
-            return &_bat_voltage;
-            break;
-        case 1:
-            return &_bat_current;
-            break;
-        case 2:
-            return &_vdd;
-            break;
-        default:
-            return NULL;
-    }
-}

libraries/AP_HAL_AVR/AnalogIn_APM2.cpp

@@ -1,50 +0,0 @@
-
-#include <AP_HAL.h>
-
-#include "AnalogIn.h"
-using namespace AP_HAL_AVR;
-
-extern const AP_HAL::HAL &hal;
-
-APM2AnalogIn::APM2AnalogIn () :
-    _pitot(ADCSource(0, 4.0)),
-    _bat_voltage(ADCSource(1)),
-    _bat_current(ADCSource(2)),
-    _rssi(ADCSource(3, 0.25)),
-    _vdd(ADCSource(AVR_ANALOG_PIN_VCC)),
-    AVRAnalogIn()
-{ }
-
-void APM2AnalogIn::init(void * machtichts) {
-    /* Register AVRAnalogIn::_timer_event with the scheduler. */
-    hal.scheduler->register_timer_process(_timer_event);
-    /* Register each private channel with AVRAnalogIn. */
-    _register_channel(&_pitot);
-    _register_channel(&_bat_voltage);
-    _register_channel(&_bat_current);
-    _register_channel(&_rssi);
-    _register_channel(&_vdd);
-}
-
-AP_HAL::AnalogSource* APM2AnalogIn::channel(int ch) {
-    switch(ch) {
-        case 0:
-            return &_bat_voltage;
-            break;
-        case 1:
-            return &_bat_current;
-            break;
-        case 2:
-            return &_vdd;
-            break;
-        case 3:
-            return &_pitot;
-            break;
-        case 4:
-            return &_rssi;
-            break;
-        default:
-            return NULL;
-    }
-}
-

libraries/AP_HAL_AVR/AnalogIn_Common.cpp

@@ -18,7 +18,31 @@ int AVRAnalogIn::_num_channels = 0;
 int AVRAnalogIn::_active_channel = 0;
 int AVRAnalogIn::_channel_repeat_count = 0;
 
-AVRAnalogIn::AVRAnalogIn() {}
+AVRAnalogIn::AVRAnalogIn() :
+    _vcc(ADCSource(ANALOG_INPUT_BOARD_VCC))
+{}
+
+void AVRAnalogIn::init(void* machtnichts) {
+    /* Register AVRAnalogIn::_timer_event with the scheduler. */
+    hal.scheduler->register_timer_process(_timer_event);
+    /* Register each private channel with AVRAnalogIn. */
+    _register_channel(&_vcc);
+}
+
+ADCSource* AVRAnalogIn::_find_or_create_channel(int pin) {
+    for(int i = 0; i < _num_channels; i++) {
+        if (_channels[i]->_pin == pin) {
+            return _channels[i];
+        }
+    }
+    return _create_channel(pin);
+}
+
+ADCSource* AVRAnalogIn::_create_channel(int chnum) {
+    ADCSource *ch = new ADCSource(chnum);
+    _register_channel(ch);
+    return ch;
+}
 
 void AVRAnalogIn::_register_channel(ADCSource* ch) {
     if (_num_channels >= AVR_INPUT_MAX_CHANNELS) {
@@ -43,6 +67,11 @@ void AVRAnalogIn::_register_channel(ADCSource* ch) {
 }
 
 void AVRAnalogIn::_timer_event(uint32_t t) {
+
+    if (_channels[_active_channel]->_pin == ANALOG_INPUT_NONE) {
+        goto next_channel;
+    }
+
     if (ADCSRA & _BV(ADSC)) {
         /* ADC Conversion is still running - this should not happen, as we
          * are called at 1khz. */
@@ -64,11 +93,14 @@ void AVRAnalogIn::_timer_event(uint32_t t) {
     }
 
     /* Read the conversion registers. */
-    uint8_t low = ADCL;
-    uint8_t high = ADCH;
-    uint16_t sample = low | (((uint16_t)high) << 8);
-    /* Give the active channel a new sample */
-    _channels[_active_channel]->new_sample( sample );
+    {
+        uint8_t low = ADCL;
+        uint8_t high = ADCH;
+        uint16_t sample = low | (((uint16_t)high) << 8);
+        /* Give the active channel a new sample */
+        _channels[_active_channel]->new_sample( sample );
+    }
+next_channel:
     /* Move to the next channel */
     _active_channel = (_active_channel + 1) % _num_channels;
     /* Setup the next channel's conversion */
@@ -78,4 +110,11 @@ void AVRAnalogIn::_timer_event(uint32_t t) {
 }
 
 
+AP_HAL::AnalogSource* AVRAnalogIn::channel(int ch) {
+    if (ch == ANALOG_INPUT_BOARD_VCC) {
+            return &_vcc;
+    } else {
+        return _find_or_create_channel(ch);
+    }
+}