From 8b28ecc8cfb9ddbedc334baa0c8ac95f2af9af1e Mon Sep 17 00:00:00 2001
From: fvanroie <15969459+fvanroie@users.noreply.github.com>
Date: Fri, 2 Jul 2021 16:05:35 +0200
Subject: [PATCH] Add M5Stack Core2 backlight dimming

---
 src/dev/esp32/m5stackcore2.cpp | 45 +++++++++++++++++++++++++++++-----
 src/dev/esp32/m5stackcore2.h   | 10 ++++++++
 2 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/src/dev/esp32/m5stackcore2.cpp b/src/dev/esp32/m5stackcore2.cpp
index 6fa16ee4..5f77dc7d 100644
--- a/src/dev/esp32/m5stackcore2.cpp
+++ b/src/dev/esp32/m5stackcore2.cpp
@@ -20,6 +20,7 @@ void M5StackCore2::init(void)
 
     Axp.SetCHGCurrent(AXP192::kCHG_100mA);
     Axp.SetLcdVoltage(2800);
+    _backlight_power = true;
 
     Axp.SetBusPowerMode(0);
     Axp.SetCHGCurrent(AXP192::kCHG_190mA);
@@ -44,16 +45,49 @@ void M5StackCore2::init(void)
     Axp.SetLed(1);
 }
 
+void M5StackCore2::set_backlight_level(uint8_t level)
+{
+    _backlight_level = level;
+    update_backlight();
+}
+
+uint8_t M5StackCore2::get_backlight_level()
+{
+    return _backlight_level;
+}
+
+void M5StackCore2::set_backlight_power(bool power)
+{
+    _backlight_power = power;
+    update_backlight();
+}
+
+bool M5StackCore2::get_backlight_power()
+{
+    return _backlight_power;
+}
+
+void M5StackCore2::update_backlight()
+{
+    if(_backlight_power) {
+        uint16_t voltage = map(_backlight_level, 0, 255, 2500, 3300);
+        Axp.SetLcdVoltage(voltage);
+    } else {
+        Axp.SetDCVoltage(2, 2200);
+    }
+    // Axp.SetDCDC3(_backlight_power); // LCD backlight
+}
+
 void M5StackCore2::get_sensors(JsonDocument& doc)
 {
     Esp32Device::get_sensors(doc);
 
-    JsonObject sensor              = doc.createNestedObject(F("AXP192"));
-    sensor[F("BattVoltage")]       = Axp.GetBatVoltage();
-    sensor[F("BattPower")]         = Axp.GetBatPower();
-   // sensor[F("Batt%")]             = Axp.getBattPercentage();
+    JsonObject sensor        = doc.createNestedObject(F("AXP192"));
+    sensor[F("BattVoltage")] = Axp.GetBatVoltage();
+    sensor[F("BattPower")]   = Axp.GetBatPower();
+    // sensor[F("Batt%")]             = Axp.getBattPercentage();
     sensor[F("BattChargeCurrent")] = Axp.GetBatChargeCurrent();
-    sensor[F("Temperature")]         = Axp.GetTempInAXP192();
+    sensor[F("Temperature")]       = Axp.GetTempInAXP192();
     sensor[F("Charging")]          = Axp.isCharging();
 }
 
@@ -62,4 +96,3 @@ void M5StackCore2::get_sensors(JsonDocument& doc)
 dev::M5StackCore2 haspDevice;
 
 #endif
-
diff --git a/src/dev/esp32/m5stackcore2.h b/src/dev/esp32/m5stackcore2.h
index b602c37a..97e39828 100644
--- a/src/dev/esp32/m5stackcore2.h
+++ b/src/dev/esp32/m5stackcore2.h
@@ -14,6 +14,16 @@ class M5StackCore2 : public Esp32Device {
   public:
     void init() override;
     void get_sensors(JsonDocument& doc);
+
+    void set_backlight_level(uint8_t level);
+    uint8_t get_backlight_level();
+    void set_backlight_power(bool power);
+    bool get_backlight_power();
+    void update_backlight();
+
+  private:
+    uint8_t _backlight_level;
+    uint8_t _backlight_power;
 };
 
 } // namespace dev