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IR-RX Development and Testing

Capture remote-control codes​

getevent -lp
getevent -l /dev/input/eventX
hexdump -C /dev/input/eventX

Distinguish the vendor/address code, protocol scan code, and Linux keycode. The kernel rc keymap converts the protocol scan code to a Linux keycode, and Android then maps the Linux keycode through a .kl file.

Android mapping path​

IR pulses -> IR-RX decode -> rc keymap -> Linux input keycode
          -> /vendor/usr/keylayout/*.kl -> Android KeyEvent

When getevent reports the key but the application does not react, the kernel path is usually working; inspect the .kl mapping, reserved system keys, and application focus.

Wakeup validation​

echo mem > /sys/power/state
# Press the remote power key
cat /sys/power/wakeup_count
cat /sys/kernel/debug/wakeup_sources | grep -i ir

Fake-poweroff wakeup also requires U-Boot and the kernel to use the same pin, vendor code, and power-key code.

Common build and flash workflow​

cd <ANDROID_TOP>/longan
./build.sh kernel
./build.sh pack

After flashing, confirm the kernel/DTB build timestamp and version so that new changes are not evaluated on an old image.