Power management progress

src/power/Consumptions.h

@@ -0,0 +1,34 @@
+/**
+ * @file Consumptions.h
+ * @author Phillip Kühne
+ * @brief 
+ * @version 0.1
+ * @date 2024-11-28
+ * 
+ * @copyright (c) 2024
+ * 
+ */
+
+#ifndef Consumptions_h
+#define Consumptions_h
+
+// The power budget afforded by the LIR2450 button cell, 700mW
+#define POWER_BUDGET 700 
+
+// The power consumptions of the different components are defined here.
+// These are "typical worst case" values for now.
+#define CONSUMPTION_ESP_BASE 96
+#define CONSUMPTION_ESP_LOAD 100
+#define CONSUMPTION_RGB_LED 56
+#define CONSUMPTION_IR_BOTTOM 327
+#define CONSUMPTION_IR_FRONT 492
+#define CONSUMPTION_OLED 92 // Assumes lots of lit pixels
+#define CONSUMPTION_MOTOR 323
+// These are placeholders for completeness for now
+#define CONSUMPTION_RGBW_SENSOR 1
+#define CONSUMPTION_IR_PT 1
+#define CONSUMPTION_UV_LED 200
+#define CONSUMPTION_IMU 1
+
+
+#endif //Consumptions_h

src/power/Power.cpp

@@ -4,21 +4,46 @@
  * @brief This component provides utilities for keeping track of power usage
  * consumption.
  * @version 0.1
- * @date 2024-11-23 
+ * @date 2024-11-23
  */
 
 #include "Power.h"
+static portMUX_TYPE mux;
 
 Power::Power()
 {
-    this->free_power_budget = this->total_power_budget;
+    this->freePowerBudget = this->totalPowerBudget;
+}
+
+void Power::begin()
+{
+    if (powerInstance == nullptr)
+    {
+        // Double check locking https://www.aristeia.com/Papers/DDJ%5FJul%5FAug%5F2004%5Frevised.pdf
+        taskENTER_CRITICAL(&mux);
+        if (powerInstance == nullptr)
+        {
+            powerInstance = new Power();
+        }
+        taskEXIT_CRITICAL(&mux);
+    }
+    else
+    {
+        // Power.begin() was called twice!
+        Serial.println("Power.begin() was called twice! No harm done, but this is a bug.");
+    }
+}
+
+Power *Power::getPowerManager()
+{
+    return powerInstance;
 }
 
 bool Power::tryAccquirePowerAllowance(uint16_t neededPower)
 {
-    if (this->free_power_budget >= neededPower)
+    if (this->freePowerBudget >= neededPower)
     {
-        this->free_power_budget -= neededPower;
+        this->freePowerBudget -= neededPower;
         return true;
     }
     else
@@ -29,12 +54,69 @@ bool Power::tryAccquirePowerAllowance(uint16_t neededPower)
 
 void Power::releasePower(uint16_t power)
 {
-    if (this->free_power_budget + power <= this->total_power_budget)
+    if (this->freePowerBudget + power <= this->totalPowerBudget)
     {
-        this->free_power_budget += power;
+        this->freePowerBudget += power;
     }
     else // TODO: Maybe we should actually throw an error here, since obviouslsy someone used us wrong.
     {
-        this->free_power_budget = this->total_power_budget;
+        this->freePowerBudget = this->totalPowerBudget;
+    }
+    // Check if there are tasks waiting for power
+    checkWaitingTasks();
+}
+
+bool Power::waitForPowerAllowance(uint16_t neededPower, TickType_t ticksToWait)
+{
+    if (tryAccquirePowerAllowance(neededPower))
+    {
+        return true;
+    }
+    else
+    {
+        // Suspend the task while waiting for power to be available
+        TaskHandle_t currentTask = xTaskGetCurrentTaskHandle();
+        TickType_t initialTickCount = xTaskGetTickCount();
+        waitingTasks.push(currentTask);
+        uint32_t notificationValue;
+        BaseType_t notificationStatus = xTaskNotifyWait(0, 0, &notificationValue, ticksToWait);
+        // Code below will be executed after the task is woken up
+        while (notificationStatus == pdPASS)
+        {
+            if (notificationValue == POWER_AVAILABLE)
+            {
+                // We were woken up because new power is available, check if it is enough
+                if (tryAccquirePowerAllowance(neededPower))
+                {
+                    return true;
+                }
+                else
+                {
+                    // Still not enough power available for us. Wait the remaining ticks.
+                    xTaskNotifyWait(0, 0, &notificationValue, ticksToWait - (xTaskGetTickCount() - initialTickCount));
+                }
+            }
+        }
+        if (notificationStatus == pdFALSE)
+        {
+            // We waited long enough...
+            return false;
+        }
+        else
+        {
+            // Should be impossible to reach
+            throw "Reached impossible state";
+        }
+    }
+}
+
+void Power::checkWaitingTasks(void)
+{
+    // Check if there are tasks waiting for power
+    if (!waitingTasks.empty())
+    {
+        TaskHandle_t task = waitingTasks.front();
+        waitingTasks.pop();
+        xTaskNotify(task, POWER_AVAILABLE, eSetValueWithOverwrite);
     }
 }

src/power/Power.h

@@ -7,29 +7,54 @@
  * @date 2024-11-23 
  */
 
+#include <queue>
 #include <Arduino.h>
+#include "Consumptions.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 #ifndef Power_h
 #define Power_h
 
-#define TOTAL_POWER_MILLIWATTS  700
+#define TOTAL_POWER_MILLIWATTS  POWER_BUDGET
+
+enum TaskResumptionReason {
+    POWER_AVAILABLE,
+    TIMEOUT
+};
 
 class Power {
     protected:
-    static const uint16_t total_power_budget = TOTAL_POWER_MILLIWATTS;
-    uint16_t free_power_budget;
+    static const uint16_t totalPowerBudget = TOTAL_POWER_MILLIWATTS;
+    uint16_t freePowerBudget;
+    std::queue<TaskHandle_t> waitingTasks;
+    void checkWaitingTasks(void);
+    bool takePowerIfAvailable(uint16_t neededPower);
+    static Power* powerInstance;
+    Power();
 
     public:
-    Power();
+    static void begin();
+    /// @brief Initialize the singleton instance of the power manager
+    /// @return reference to the power manager
+    static Power *getPowerManager();
     uint16_t getFreePowerBudget(void);
     /// @brief Request an allowance of a certain number of milliwatts from the power scheduler
     /// @param neededPower the amount of power we want to be accounted for (in mW)
     /// @return whether the power could be successfully allocated
     bool tryAccquirePowerAllowance(uint16_t neededPower);
     /// @brief "Return" a certain amount of power when it is no longer needed
-    /// @param power the amount of power to return (in mW)
+    /// @param neededPower the amount of power to return (in mW)
     /// @return whether the power
     void releasePower(uint16_t power);
+
+    /// @brief Wait for a certain amount of power to be available
+    /// @param neededPower the amount of power we want to be accounted for (in mW)
+    /// @param TicksToWait the amount of time to wait for the power to become available
+    /// @return whether the power could be successfully allocatedy
+    bool waitForPowerAllowance(uint16_t neededPower,TickType_t TicksToWait);
+    /// @brief Put the ESP32 into deep sleep mode, without a method to wake up again. Basically this is a shutdown.
+    void beginPermanentDeepSleep(void);
 };
 
 #endif //Power