Implemented new driver projects (#210)

Moved drivers from the `Boards` projects to `Drivers` folder:
- BQ24295
- AW9523
- AXP2101

The I2C drivers are theoretically cross-platform, but for now they are only built for ESP32.

Drivers/AXP2101/CMakeLists.txt

@@ -0,0 +1,5 @@
+idf_component_register(
+    SRC_DIRS "Source"
+    INCLUDE_DIRS "Source"
+    REQUIRES Tactility
+)

Drivers/AXP2101/README.md

@@ -0,0 +1,6 @@
+# AXP2101
+
+Power management with I2C interface: a single cell NVDC PMU with E-gauge.
+
+- [Datasheet](http://file.whycan.com/files/members/6736/AXP2101_Datasheet_V1.0_en_3832.pdf)
+- [M5Unified implementation](https://github.com/m5stack/M5Unified/blob/master/src/utility/AXP2101_Class.cpp)

Drivers/AXP2101/Source/Axp2101.cpp

@@ -0,0 +1,59 @@
+#include "Axp2101.h"
+#include <Tactility/Log.h>
+
+bool Axp2101::getBatteryVoltage(float& vbatMillis) const {
+    return readRegister14(0x34, vbatMillis);
+}
+
+bool Axp2101::getChargeStatus(ChargeStatus& status) const {
+    uint8_t value;
+    if (readRegister8(0x01, value)) {
+        value = (value >> 5) & 0b11;
+        status = (value == 1) ? CHARGE_STATUS_CHARGING : ((value == 2) ? CHARGE_STATUS_DISCHARGING : CHARGE_STATUS_STANDBY);
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Axp2101::isChargingEnabled(bool& enabled) const {
+    uint8_t value;
+    if (readRegister8(0x18, value)) {
+        enabled = value & 0b10;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Axp2101::setChargingEnabled(bool enabled) const {
+    uint8_t value;
+    if (readRegister8(0x18, value)) {
+        return writeRegister8(0x18, (value & 0xFD) | (enabled << 1));
+    } else {
+        return false;
+    }
+}
+
+bool Axp2101::isVBus() const {
+    uint8_t value;
+    return readRegister8(0x00, value) && (value & 0x20);
+}
+
+bool Axp2101::getVBusVoltage(float& out) const {
+    if (!isVBus()) {
+        return false;
+    } else {
+        float vbus;
+        if (readRegister14(0x38, vbus) && vbus < 16375) {
+            out = vbus / 1000.0f;
+            return true;
+        } else {
+            return false;
+        }
+    }
+}
+
+bool Axp2101::setRegisters(uint8_t* bytePairs, size_t bytePairsSize) const {
+    return tt::hal::i2c::masterWriteRegisterArray(port, address, bytePairs, bytePairsSize, DEFAULT_TIMEOUT);
+}

Drivers/AXP2101/Source/Axp2101.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <Tactility/hal/i2c/I2cDevice.h>
+
+#define AXP2101_ADDRESS 0x34
+
+/**
+ * References:
+ * - https://github.com/m5stack/M5Unified/blob/master/src/utility/AXP2101_Class.cpp
+ * - http://file.whycan.com/files/members/6736/AXP2101_Datasheet_V1.0_en_3832.pdf
+ */
+class Axp2101 final : public tt::hal::i2c::I2cDevice {
+
+public:
+
+    enum ChargeStatus {
+        CHARGE_STATUS_CHARGING = 0b01,
+        CHARGE_STATUS_DISCHARGING = 0b10,
+        CHARGE_STATUS_STANDBY = 0b00
+    };
+
+    explicit Axp2101(i2c_port_t port) : I2cDevice(port, AXP2101_ADDRESS) {}
+
+    std::string getName() const final { return "AXP2101"; }
+    std::string getDescription() const final { return "Power management with I2C interface."; }
+
+    bool setRegisters(uint8_t* bytePairs, size_t bytePairsSize) const;
+
+    bool getBatteryVoltage(float& vbatMillis) const;
+    bool getChargeStatus(ChargeStatus& status) const;
+    bool isChargingEnabled(bool& enabled) const;
+    bool setChargingEnabled(bool enabled) const;
+
+    bool isVBus() const;
+    bool getVBusVoltage(float& out) const;
+};