uconsole-sleep

This is a Rust port of uConsole-sleep. It provides a power key monitor that toggles between normal and power-saving modes. Passed tests on uConsole cm4 with RPI Trixie OS.

Binary:

• Monitor the power key and toggle power-saving mode on short press.

Power-saving mode includes:

• Display off (backlight control via sysfs)
• Reduced CPU frequency (configurable via SAVING_CPU_FREQ)
• Future extensibility: WiFi control, Bluetooth control, etc.

Environment variables:

• SAVING_CPU_FREQ — set to min,max in MHz (e.g. 100,600) to apply when in power-saving mode
• HOLD_TRIGGER_SEC — float seconds to treat as a long press (default 0.7)

Build:

cargo build --release

Usage (run as root to write sysfs, grab input device, and manage power):

sudo ./target/release/uconsole-sleep

To override the configuration location

default /etc/uconsole-sleep/config or repo ./etc/uconsole-sleep/config.default

sudo ./target/release/uconsole-sleep --config /path/to/config

• Use RUST_LOG environment variable to control logging level (e.g. RUST_LOG=debug) or CLI flags -v (info), -vv (debug), -vvv (trace).
• Run uconsole-sleep -h or uconsole-sleep --help to print usage and available options such as --dry-run, --toggle-wifi, --toggle-bt, and --config.

Examples:

# Dry run (no writes)
sudo ./target/release/uconsole-sleep --dry-run
# Show help
sudo ./target/release/uconsole-sleep --help

How it works:

• Press power key (short press < 0.7s): toggle between normal and power-saving mode
• Power-saving mode: turns off display, reduces CPU frequency
• Normal mode: turns on display, restores default CPU frequency
• The program grabs exclusive access to the power key device to prevent LXDE from triggering shutdown dialogs

Notes:

• This implementation uses sysfs writes to toggle display and CPU frequency
• The power key device is grabbed (EVIOCGRAB) to prevent desktop environment conflicts
• Tests cover hardware detection helpers