Fix T-Deck battery estimate

modules/core_sys/include/platform/ui/device_runtime.h

@@ -30,6 +30,8 @@ MemoryStats memory_stats();
 const char* firmware_version();
 void handle_low_battery(const BatteryInfo& info);
 bool supports_screen_brightness();
+bool supports_configurable_battery_gauge();
+void reload_configurable_battery_gauge();
 uint8_t screen_brightness();
 void set_screen_brightness(uint8_t level);
 void trigger_haptic();

modules/core_sys/include/power/battery_estimator.h

@@ -0,0 +1,62 @@
+#pragma once
+
+#include <cstdint>
+
+namespace power
+{
+
+struct BatteryEstimatorSample
+{
+    uint32_t now_ms = 0;
+    int pmu_percent = -1;
+    int pmu_battery_mv = -1;
+    int adc_battery_mv = -1;
+    bool charging = false;
+    bool vbus_present = false;
+};
+
+enum class BatteryEstimateReason
+{
+    NoSample,
+    PmuPercent,
+    VoltageFallback,
+    ChargerStableHold,
+    DetachStableHold,
+    DropGuard,
+    ZeroGuard,
+    RateLimited,
+};
+
+struct BatteryEstimate
+{
+    BatteryEstimate() = default;
+    BatteryEstimate(int percent_value, BatteryEstimateReason reason_value)
+        : percent(percent_value), reason(reason_value)
+    {
+    }
+
+    int percent = -1;
+    BatteryEstimateReason reason = BatteryEstimateReason::NoSample;
+};
+
+class BatteryEstimator
+{
+  public:
+    BatteryEstimate update(const BatteryEstimatorSample& sample);
+    int lastPercent() const { return last_percent_; }
+    uint32_t lastVbusDetachMs() const { return last_vbus_detach_ms_; }
+    void reset();
+
+  private:
+    int last_percent_ = -1;
+    uint32_t last_sample_ms_ = 0;
+    uint32_t last_vbus_detach_ms_ = 0;
+    bool has_last_power_state_ = false;
+    bool last_vbus_present_ = false;
+    bool last_charging_ = false;
+    uint8_t zero_streak_ = 0;
+};
+
+int batteryPercentFromLipoMillivolts(int mv);
+
+} // namespace power