Features - KVantage

Overview

KVantage provides essential hardware control features for Lenovo laptops on Linux. All features interact directly with your laptop’s ACPI interface to provide the same functionality you’d find in Lenovo Vantage on Windows.

All features require the application to be running with root privileges to access the ACPI interface at /proc/acpi/call.

Core Features

Performance Profiles

Switch between three power profiles to optimize for performance or battery life

Battery Conservation

Limit battery charge to 80% to extend battery lifespan

Rapid Charge

Enable fast charging when you need quick battery top-ups

Battery Monitoring

Real-time battery level display with visual progress indicator

Theme Customization

Multiple beautiful themes with animated backgrounds

Multi-language

Support for 8 languages with automatic locale detection

Performance Profiles

Control your laptop’s performance mode to balance between power and efficiency. The application provides three distinct profiles:

Available Modes

Extreme Performance (0x0012B001)

Maximizes CPU and GPU performance for demanding tasks. Your laptop will run at higher clock speeds and may generate more heat and noise.ACPI Command: \_SB.PCI0.LPC0.EC0.VPC0.DYTC 0x0012B001Best for: Gaming, video editing, 3D rendering, compilation tasks

Intelligent Cooling / Balanced (0x000FB001)

The default balanced mode that intelligently adjusts performance based on workload. Provides good performance while managing thermals.ACPI Command: \_SB.PCI0.LPC0.EC0.VPC0.DYTC 0x000FB001Best for: General productivity, web browsing, light development

Power Saving (0x0013B001)

Prioritizes battery life by reducing performance. Ideal for extending battery runtime when away from power.ACPI Command: \_SB.PCI0.LPC0.EC0.VPC0.DYTC 0x0013B001Best for: Reading, note-taking, traveling, extending battery life

How It Works

The performance profiles are implemented using a segmented button control in the UI:

// From PowerProfiler.kt
val result = kvand.sendCommand("get performance")
val sanitizedResult = result.replace("\u0000", "").trim()
selectedIndex = when (sanitizedResult) {
    "0x0" -> 1 // Extreme Performance
    "0x1" -> 0 // Intelligent Cooling (Balanced)
    else -> 2 // Power Saving
}

The application reads the current performance mode on startup and displays it with visual icons:

⚡ Bolt icon for Extreme Performance
💨 Air icon for Intelligent Cooling
🍃 Leaf icon for Power Saving

Changes to performance profiles take effect immediately and persist until you change them again or restart your laptop.

Battery Conservation Mode

Battery Conservation Mode limits your battery charge to 80% to significantly extend your battery’s lifespan. This is especially useful if you primarily use your laptop while plugged in.

Why 80%?

Lithium-ion batteries last longer when kept between 20% and 80% charge. By limiting the maximum charge to 80%, you can potentially double your battery’s lifespan.

Implementation Details

// From BatteryThreshold.kt
val result = kvand.sendCommand("get conservation")
val sanitizedResult = result.replace("\u0000", "").trim()
isChecked = sanitizedResult == "0x1"

ACPI Commands:

Enable: \_SB.PCI0.LPC0.EC0.VPC0.SBMC 0x03
Disable: \_SB.PCI0.LPC0.EC0.VPC0.SBMC 0x05
Status Query: \_SB.PCI0.LPC0.EC0.BTSM

Battery Conservation Mode is automatically disabled when Rapid Charge is enabled, as the two features are mutually exclusive.

User Interface

The feature includes:

A toggle switch to enable/disable conservation mode
An explanatory warning message when enabled
Automatic conflict resolution with Rapid Charge

Custom battery threshold values (other than 80%) are not currently supported. This feature may be added in the future based on user demand and hardware testing availability.

Rapid Charge

Rapid Charge enables faster battery charging when you need a quick power boost. When enabled, your laptop will charge at higher currents to fill the battery faster.

Trade-offs

Advantages:

Significantly faster charging times
Useful when you need to charge quickly between meetings
Can be toggled on-demand

Disadvantages:

Higher heat generation during charging
Slightly reduced long-term battery health if used constantly
Incompatible with Battery Conservation Mode

Implementation

// From RapidCharge.kt
val result = kvand.sendCommand("get rapid")
val sanitizedResult = result.replace("\u0000", "").trim()
isChecked = sanitizedResult == "0x1"

ACPI Commands:

Enable: \_SB.PCI0.LPC0.EC0.VPC0.SBMC 0x07
Disable: \_SB.PCI0.LPC0.EC0.VPC0.SBMC 0x08
Status Query: \_SB.PCI0.LPC0.EC0.QCHO

When you enable Rapid Charge, Battery Conservation Mode is automatically disabled to prevent conflicts.

Battery Life Monitoring

KVantage displays your current battery level with a beautiful visual progress indicator. This feature can be toggled on or off in the settings.

Display Features

Visual Progress Bar: Horizontal bar showing charge level from 0% to 100%
Percentage Display: Precise battery level shown as a decimal (e.g., 87.3%)
Color Coding: Uses theme colors for visual consistency
Error Handling: Graceful fallback if battery interface is not found

// From BatteryLife.kt - Display logic
LinearProgressIndicator(
    progress = remainingLife / 100F,
    color = MaterialTheme.colorScheme.tertiary,
    backgroundColor = MaterialTheme.colorScheme.tertiaryContainer,
    modifier = Modifier.size(300.dp, 15.dp).clip(RoundedCornerShape(20))
)

Battery Detection

The application reads battery information from /sys/class/power_supply/ and allows you to configure which battery device to monitor (default: BAT0).

Error States

The battery monitor handles two error conditions:Interface Not Found (-1)

Displayed when the battery interface cannot be accessed
Shows message: “Battery interface not found”

Parsing Failed (0)

Occurs when battery data cannot be parsed correctly
Shows message: “Battery parsing failed”

Settings

You can:

Toggle visibility: Show or hide the battery indicator entirely
Configure battery name: Change from BAT0 to BAT1 or other battery devices
Settings persist between application sessions

Visual Customization

Themes

KVantage includes four beautiful themes, each available in dark and light variants:

Whispering Sea

The default theme with calming ocean-inspired colors and optional animated gradient background

Material

Classic Material Design colors with clean, professional aesthetics

Kanagawa

Inspired by traditional Japanese art, featuring muted, sophisticated colors

Dracula

Popular dark theme with vibrant accents and excellent contrast

Theme Implementation

// From ThemeType.kt
enum class ThemeType (val index: Int) {
    SEA (0),
    MATERIAL (1),
    KANAGAWA (2),
    DRACULA (3);
}

Each theme provides carefully selected color palettes for:

Primary, secondary, and tertiary colors
Surface and background colors
Text and icon colors with proper contrast
Active and inactive states

Animated Backgrounds

The Whispering Sea theme includes an optional animated gradient background that creates a subtle, flowing effect.

You can toggle animated backgrounds in the settings:

Enabled: Beautiful gradient animations enhance the visual experience
Disabled: Static background for better performance or personal preference

Dark and Light Modes

Every theme supports both dark and light variants:

Toggle between modes in settings
Proper contrast maintained in both modes
All UI elements adapt to the selected mode

// From Settings.kt - Theme configuration
data class Settings(
    val isDarkMode: Boolean = false,
    val isAnimatedBackground: Boolean = true,
    val isRemainingBatteryLifeVisible: Boolean = true,
    val batteryName: String = "BAT0",
    val selectedThemeIndex: Int = 0
)

Internationalization

KVantage automatically detects your system locale and displays the interface in your language.

Supported Languages

English (en) - Native translation
Spanish (es) - Native translation
Japanese (ja) - Native translation
German (de) - AI-assisted translation
French (fr) - AI-assisted translation
Portuguese (pt) - AI-assisted translation
Korean (kr) - AI-assisted translation
Chinese (zh) - AI-assisted translation

The application automatically switches language based on your system’s locale setting. English, Spanish, and Japanese translations were created by the developer, while other languages use AI-assisted translations.

Implementation

All strings are managed through Compose Multiplatform’s resource system:

// Example: Using localized strings
Text(
    text = stringResource(Res.string.performance_profile),
    fontSize = 20.sp,
    color = MaterialTheme.colorScheme.onSurface
)

Localization files are located in:

/composeResources/values/strings.xml (English)
/composeResources/values-es/strings.xml (Spanish)
/composeResources/values-ja/strings.xml (Japanese)
And so on for each supported language

Settings Management

All your preferences are automatically saved and restored:

Persisted Settings

Selected theme and color mode (dark/light)
Animated background preference
Battery life visibility
Battery device name
Selected theme index

Settings Dialog

Access comprehensive settings through the settings dialog:

// Settings are managed through SettingsManager utility
// All changes are automatically saved to disk

The settings dialog provides:

Theme Controls: Toggle dark mode and select theme
Animation Controls: Enable/disable animated backgrounds
Battery Controls: Show/hide battery monitor and configure device name
Visual Preview: Changes apply immediately

Settings are stored in your user’s application data directory and persist between sessions.

Planned Features

System Tray Support

System tray icon support is planned for a future release. Recent improvements to Compose Multiplatform’s Linux support make this feature more feasible.

Status: Under considerationFrom the developer: “Compose Multiplatform has evolved a lot in the last year, so this might now be possible! I will look into this later.”

Previous limitations with Linux tray support included:

Poor built-in tray detection on Linux desktop environments
Compatibility issues with KDE, Cinnamon, and Hyprland
Third-party library limitations

Custom Battery Thresholds

The ability to set custom battery charge thresholds (other than 80%) may be implemented in the future based on:

User demand and feedback
Availability of hardware for testing
ACPI interface support verification

Technical Architecture

Frontend-Backend Communication

The application uses a simple command-based protocol between the GUI and daemon:

// Backend command examples from main.go
"get performance"  // Query current performance mode
"set performance 0" // Set to Intelligent Cooling
"get conservation" // Check battery conservation status
"set conservation 1" // Enable battery conservation
"get rapid"       // Check rapid charge status
"set rapid 0"     // Disable rapid charge

ACPI Interface

All hardware control is performed through /proc/acpi/call:

// From main.go - ACPI paths
const (
    GetBattConservationStatus   = "\\_SB.PCI0.LPC0.EC0.BTSM"
    GetRapidChargeStatus        = "\\_SB.PCI0.LPC0.EC0.QCHO"
    GetPerformanceModeStatus    = "\\_SB.PCI0.LPC0.EC0.SPMO"
)

Important: ACPI write operations take approximately 1 second to complete and take effect. The GUI handles this asynchronously to prevent freezing.

State Management

The application uses Compose state management with coroutines:

// State is fetched asynchronously on component initialization
LaunchedEffect(Unit) {
    val result = withContext(Dispatchers.IO) {
        kvand.sendCommand("get performance")
    }
    // Update UI state
}

All hardware state queries and updates happen on IO dispatchers to keep the UI responsive.

Feature Summary

Current Features

✅ Performance profile switching (3 modes)✅ Battery conservation mode (80% limit)✅ Rapid charge toggle✅ Battery life monitoring with optional display✅ 4 themes with dark/light variants✅ Animated backgrounds✅ 8 language translations✅ Settings persistence✅ Embedded installer

Future Considerations

⏳ System tray icon support⏳ Custom battery threshold values

For installation instructions, system requirements, and troubleshooting, see the Quickstart Guide.

Overview

Getting Started

Core Features

Architecture

Troubleshooting

Contributing

​Overview

​Core Features

Performance Profiles

Battery Conservation

Rapid Charge

Battery Monitoring

Theme Customization

Multi-language

​Performance Profiles

​Available Modes

​How It Works

​Battery Conservation Mode

​Why 80%?

​Implementation Details

​User Interface

​Rapid Charge

​Trade-offs

​Implementation

​Battery Life Monitoring

​Display Features

​Battery Detection

​Settings

​Visual Customization

​Themes

Whispering Sea

Material

Kanagawa

Dracula

​Theme Implementation

​Animated Backgrounds

​Dark and Light Modes

​Internationalization

​Supported Languages

​Implementation

​Settings Management

​Persisted Settings

​Settings Dialog

​Planned Features

​System Tray Support

​Custom Battery Thresholds

​Technical Architecture

​Frontend-Backend Communication

​ACPI Interface

​State Management

​Feature Summary

Current Features

Future Considerations

Build docs developers (and LLMs) love

Overview

Core Features

Performance Profiles

Available Modes

How It Works

Battery Conservation Mode

Why 80%?

Implementation Details

User Interface

Rapid Charge

Trade-offs

Implementation

Battery Life Monitoring

Display Features

Battery Detection

Settings

Visual Customization

Themes

Theme Implementation

Animated Backgrounds

Dark and Light Modes

Internationalization

Supported Languages

Implementation

Settings Management

Persisted Settings

Settings Dialog

Planned Features

System Tray Support

Custom Battery Thresholds

Technical Architecture

Frontend-Backend Communication

ACPI Interface

State Management

Feature Summary