Implemented power management (#67)

- Implemented HAL for for power management
- Implemented the Power app (accessible via Settings app)
- Implemented status bar icon for battery status

boards/m5stack_core2/source/display.cpp

@@ -32,7 +32,12 @@ lv_disp_t* core2_display_init() {
     const esp_lcd_panel_dev_config_t panel_config = {
         .reset_gpio_num = GPIO_NUM_NC,
         .rgb_ele_order = LCD_RGB_ELEMENT_ORDER_BGR,
+        .data_endian = LCD_RGB_DATA_ENDIAN_BIG,
         .bits_per_pixel = CORE2_LCD_BITS_PER_PIXEL,
+        .flags = {
+            .reset_active_high = false
+        },
+        .vendor_config = nullptr
     };
 
     esp_lcd_panel_handle_t panel_handle;

boards/m5stack_core2/source/m5stack_core2.c

@@ -3,6 +3,7 @@
 #include "lvgl_i.h"
 
 extern const SdCard core2_sdcard;
+extern Power core2_power; // Making it const fails the build
 
 const HardwareConfig m5stack_core2 = {
     .bootstrap = &core2_bootstrap,
@@ -10,5 +11,6 @@ const HardwareConfig m5stack_core2 = {
         .set_backlight_duty = NULL
     },
     .init_graphics = &core2_lvgl_init,
-    .sdcard = &core2_sdcard
+    .sdcard = &core2_sdcard,
+    .power = &core2_power
 };

boards/m5stack_core2/source/power.cpp

@@ -0,0 +1,34 @@
+#include "power.h"
+#include "M5Unified.hpp"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+static bool power_is_charging() {
+    return M5.Power.isCharging() == m5::Power_Class::is_charging;
+}
+
+static void power_set_charging_enabled(bool enabled) {
+    M5.Power.setBatteryCharge(enabled);
+}
+
+static uint8_t power_get_charge_level() {
+    uint16_t scaled = (uint16_t)M5.Power.getBatteryLevel() * 255 / 100;
+    return (uint8_t)scaled;
+}
+
+static int32_t power_get_current() {
+    return M5.Power.getBatteryCurrent();
+}
+
+Power core2_power = {
+    .is_charging = &power_is_charging,
+    .set_charging_enabled = &power_set_charging_enabled,
+    .get_charge_level = &power_get_charge_level,
+    .get_current = &power_get_current
+};
+
+#ifdef __cplusplus
+}
+#endif

boards/m5stack_core2/source/touch.cpp

@@ -9,7 +9,7 @@ extern "C" {
 #endif
 
 static void read_touch(TT_UNUSED lv_indev_t* indev, lv_indev_data_t* data) {
-    static lgfx::touch_point_t point;
+    lgfx::touch_point_t point; // Making it static makes it unreliable
     bool touched = M5.Lcd.getTouch(&point) > 0;
     if (touched) {
         data->point.x = point.x;