1. 根目录:
2. include
3. dt-bindings
4. gpio
5. gpio.h

/*
 * This header provides constants for most GPIO bindings.
 *
 * Most GPIO bindings include a flags cell as part of the GPIO specifier.
 * In most cases, the format of the flags cell uses the standard values
 * defined in this header.
 */

#ifndef _DT_BINDINGS_GPIO_GPIO_H
#define _DT_BINDINGS_GPIO_GPIO_H

#define GPIO_ACTIVE_HIGH 0
#define GPIO_ACTIVE_LOW 1

#endif