keyboard.h

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/**
 * @file keyboard.h
 * @brief Kernel generic keyboard interface.
 */
#ifndef _SYS_KEYBOARD_H
#define _SYS_KEYBOARD_H
 
#include <stdbool.h>
#include "keycode.h"
 
/**
 * @brief struct to hold state of the keyboard in terms of modifier keys
 */
struct keyboard_state {
        bool shift; /**< is shift pressed */
        bool ctrl; /**< is ctrl pressed */
        bool alt; /**< is alt or altgr pressed */
        bool caps; /**< is caps toggled */
};
 
/**
 * @brief typedef for generic hal polling function pointer.
 *
 * This allows us, when initializing the keyboard to pass a polling function (e.g.
 * ps2_poll) dynamically.
 */
typedef bool (*hal_poll_func_t)(void);
 
/**
 * @brief struct that holds a keyboard event
 *
 */
struct keyboard_event {
        bool pressed; /**< whether key was pressed or released */
        enum KEYCODE keycode; /**< the keycode of the key which was pressed */
};
 
/**
 * @brief function to initialize the kernel keyboard system
 * @param poll generic HAL keyboard polling function
 * @return whether initialization passed or failed
 */
int keyboard_init(hal_poll_func_t poll);
 
/**
 * @brief function to poll the keyboard for available events
 * @returns true if new data has been pushed to event queue
 * @note typically is called from irq.c, direct polling is slow
 */
bool keyboard_poll();
 
/**
 * @brief pop an event from the keyboard event queue.
 * @param event buffer to store new event data in
 * @returns whether there was any data in queue to pop
 */
bool keyboard_pop_event(struct keyboard_event *event);
/**
 * @brief push event to the keyboard event queue
 * @param event event to push to the queue
 * @note can be used to simulate keypresses.
 * @note This function is typically called directly from the HAL keyboard driver. See
 * ps2_keyboard.c for an example.
 */
void keyboard_push_event(struct keyboard_event event);
 
/**
 * @brief get the current modifier state of the keyboard
 * @returns a pointer to the keyboard's struct keyboard_state
 *
 */
struct keyboard_state *keyboard_get_state();
 
#endif