153 lines
3.9 KiB
C

/* Copyright 2022
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <stdbool.h>
#include <stdint.h>
#include "gpio.h"
/**
* \file
*
* \defgroup joystick HID Joystick
* \{
*/
#ifndef JOYSTICK_BUTTON_COUNT
# define JOYSTICK_BUTTON_COUNT 8
#elif JOYSTICK_BUTTON_COUNT > 32
# error Joystick feature only supports up to 32 buttons
#endif
#ifndef JOYSTICK_AXIS_COUNT
# define JOYSTICK_AXIS_COUNT 2
#elif JOYSTICK_AXIS_COUNT > 6
# error Joystick feature only supports up to 6 axes
#endif
#if JOYSTICK_AXIS_COUNT == 0 && JOYSTICK_BUTTON_COUNT == 0
# error Joystick feature requires at least one axis or button
#endif
#ifndef JOYSTICK_AXIS_RESOLUTION
# define JOYSTICK_AXIS_RESOLUTION 8
#elif JOYSTICK_AXIS_RESOLUTION < 8 || JOYSTICK_AXIS_RESOLUTION > 16
# error JOYSTICK_AXIS_RESOLUTION must be between 8 and 16
#endif
#define JOYSTICK_MAX_VALUE ((1L << (JOYSTICK_AXIS_RESOLUTION - 1)) - 1)
#define JOYSTICK_HAT_CENTER -1
#define JOYSTICK_HAT_NORTH 0
#define JOYSTICK_HAT_NORTHEAST 1
#define JOYSTICK_HAT_EAST 2
#define JOYSTICK_HAT_SOUTHEAST 3
#define JOYSTICK_HAT_SOUTH 4
#define JOYSTICK_HAT_SOUTHWEST 5
#define JOYSTICK_HAT_WEST 6
#define JOYSTICK_HAT_NORTHWEST 7
// configure on input_pin of the joystick_axes array entry to NO_PIN
// to prevent it from being read from the ADC. This allows outputting forged axis value.
#define JOYSTICK_AXIS_VIRTUAL \
{ NO_PIN, 0, JOYSTICK_MAX_VALUE / 2, JOYSTICK_MAX_VALUE }
#define JOYSTICK_AXIS_IN(INPUT_PIN, LOW, REST, HIGH) \
{ INPUT_PIN, LOW, REST, HIGH }
typedef struct {
pin_t input_pin;
// the AVR ADC offers 10 bit precision, with significant bits on the higher part
uint16_t min_digit;
uint16_t mid_digit;
uint16_t max_digit;
} joystick_config_t;
extern joystick_config_t joystick_axes[JOYSTICK_AXIS_COUNT];
typedef struct {
uint8_t buttons[(JOYSTICK_BUTTON_COUNT - 1) / 8 + 1];
int16_t axes[JOYSTICK_AXIS_COUNT];
#ifdef JOYSTICK_HAS_HAT
int8_t hat;
#endif
bool dirty;
} joystick_t;
extern joystick_t joystick_state;
/**
* \brief Handle the initialization of the subsystem.
*/
void joystick_init(void);
/**
* \brief Handle various subsystem background tasks.
*/
void joystick_task(void);
/**
* \brief Send the joystick report to the host, if it has been marked as dirty.
*/
void joystick_flush(void);
/**
* \brief Set the state of a button, and flush the report.
*
* \param button The index of the button to press, from 0 to 31.
*/
void register_joystick_button(uint8_t button);
/**
* \brief Reset the state of a button, and flush the report.
*
* \param button The index of the button to release, from 0 to 31.
*/
void unregister_joystick_button(uint8_t button);
/**
* \brief Sample and process the analog value of the given axis.
*
* \param axis The axis to read.
*
* \return A signed 16-bit integer, where 0 is the resting or mid point.
*/
int16_t joystick_read_axis(uint8_t axis);
/**
* \brief Sample and process the all axis.
*/
void joystick_read_axes(void);
/**
* \brief Set the value of the given axis.
*
* \param axis The axis to set the value of.
* \param value The value to set.
*/
void joystick_set_axis(uint8_t axis, int16_t value);
/**
* \brief Set the position of the hat switch.
*
* \param value The hat switch position to set.
*/
void joystick_set_hat(int8_t value);
/** \} */