qmk-firmware/keyboard/planck/planck.c

#include "planck.h"

__attribute__ ((weak))
void matrix_init_user(void) {}

__attribute__ ((weak))
void matrix_scan_user(void) {}

__attribute__ ((weak))
void process_action_user(keyrecord_t *record) {}

void matrix_init_kb(void) {
#ifdef BACKLIGHT_ENABLE
	backlight_init_ports();
#endif

#ifdef RGBLIGHT_ENABLE
	rgblight_init();
#endif

	// Turn status LED on
	DDRE |= (1<<6);
	PORTE |= (1<<6);

	matrix_init_user();
}

void matrix_scan_kb(void) {
	matrix_scan_user();
}

void process_action_kb(keyrecord_t *record) {
	process_action_user(record);
}