zmk/app/include/zmk/hid.h

/*
 * Copyright (c) 2020 The ZMK Contributors
 *
 * SPDX-License-Identifier: MIT
 */

#pragma once

#include <zephyr/usb/usb_device.h>
#include <zephyr/usb/class/usb_hid.h>

#include <zmk/keys.h>
#include <dt-bindings/zmk/hid_usage.h>
#include <dt-bindings/zmk/hid_usage_pages.h>

#define ZMK_HID_KEYBOARD_NKRO_MAX_USAGE HID_USAGE_KEY_KEYPAD_EQUAL

// See https://www.usb.org/sites/default/files/hid1_11.pdf section 6.2.2.4 Main Items

#define ZMK_HID_MAIN_VAL_DATA (0x00 << 0)
#define ZMK_HID_MAIN_VAL_CONST (0x01 << 0)

#define ZMK_HID_MAIN_VAL_ARRAY (0x00 << 1)
#define ZMK_HID_MAIN_VAL_VAR (0x01 << 1)

#define ZMK_HID_MAIN_VAL_ABS (0x00 << 2)
#define ZMK_HID_MAIN_VAL_REL (0x01 << 2)

#define ZMK_HID_MAIN_VAL_NO_WRAP (0x00 << 3)
#define ZMK_HID_MAIN_VAL_WRAP (0x01 << 3)

#define ZMK_HID_MAIN_VAL_LIN (0x00 << 4)
#define ZMK_HID_MAIN_VAL_NON_LIN (0x01 << 4)

#define ZMK_HID_MAIN_VAL_PREFERRED (0x00 << 5)
#define ZMK_HID_MAIN_VAL_NO_PREFERRED (0x01 << 5)

#define ZMK_HID_MAIN_VAL_NO_NULL (0x00 << 6)
#define ZMK_HID_MAIN_VAL_NULL (0x01 << 6)

#define ZMK_HID_MAIN_VAL_NON_VOL (0x00 << 7)
#define ZMK_HID_MAIN_VAL_VOL (0x01 << 7)

#define ZMK_HID_MAIN_VAL_BIT_FIELD (0x00 << 8)
#define ZMK_HID_MAIN_VAL_BUFFERED_BYTES (0x01 << 8)

#define ZMK_HID_REPORT_ID_KEYBOARD 0x01
#define ZMK_HID_REPORT_ID_CONSUMER 0x02

static const uint8_t zmk_hid_report_desc[] = {
    HID_USAGE_PAGE(HID_USAGE_GEN_DESKTOP),
    HID_USAGE(HID_USAGE_GD_KEYBOARD),
    HID_COLLECTION(HID_COLLECTION_APPLICATION),
    HID_REPORT_ID(ZMK_HID_REPORT_ID_KEYBOARD),
    HID_USAGE_PAGE(HID_USAGE_KEY),
    HID_USAGE_MIN8(HID_USAGE_KEY_KEYBOARD_LEFTCONTROL),
    HID_USAGE_MAX8(HID_USAGE_KEY_KEYBOARD_RIGHT_GUI),
    HID_LOGICAL_MIN8(0x00),
    HID_LOGICAL_MAX8(0x01),

    HID_REPORT_SIZE(0x01),
    HID_REPORT_COUNT(0x08),
    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),

    HID_USAGE_PAGE(HID_USAGE_KEY),
    HID_REPORT_SIZE(0x08),
    HID_REPORT_COUNT(0x01),
    HID_INPUT(ZMK_HID_MAIN_VAL_CONST | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),

    HID_USAGE_PAGE(HID_USAGE_KEY),

#if IS_ENABLED(CONFIG_ZMK_HID_REPORT_TYPE_NKRO)
    HID_LOGICAL_MIN8(0x00),
    HID_LOGICAL_MAX8(0x01),
    HID_USAGE_MIN8(0x00),
    HID_USAGE_MAX8(ZMK_HID_KEYBOARD_NKRO_MAX_USAGE),
    HID_REPORT_SIZE(0x01),
    HID_REPORT_COUNT(ZMK_HID_KEYBOARD_NKRO_MAX_USAGE + 1),
    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_VAR | ZMK_HID_MAIN_VAL_ABS),
#elif IS_ENABLED(CONFIG_ZMK_HID_REPORT_TYPE_HKRO)
    HID_LOGICAL_MIN8(0x00),
    HID_LOGICAL_MAX16(0xFF, 0x00),
    HID_USAGE_MIN8(0x00),
    HID_USAGE_MAX8(0xFF),
    HID_REPORT_SIZE(0x08),
    HID_REPORT_COUNT(CONFIG_ZMK_HID_KEYBOARD_REPORT_SIZE),
    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_ARRAY | ZMK_HID_MAIN_VAL_ABS),
#else
#error "A proper HID report type must be selected"
#endif

    HID_END_COLLECTION,
    HID_USAGE_PAGE(HID_USAGE_CONSUMER),
    HID_USAGE(HID_USAGE_CONSUMER_CONSUMER_CONTROL),
    HID_COLLECTION(HID_COLLECTION_APPLICATION),
    HID_REPORT_ID(ZMK_HID_REPORT_ID_CONSUMER),
    HID_USAGE_PAGE(HID_USAGE_CONSUMER),

#if IS_ENABLED(CONFIG_ZMK_HID_CONSUMER_REPORT_USAGES_BASIC)
    HID_LOGICAL_MIN8(0x00),
    HID_LOGICAL_MAX16(0xFF, 0x00),
    HID_USAGE_MIN8(0x00),
    HID_USAGE_MAX8(0xFF),
    HID_REPORT_SIZE(0x08),
#elif IS_ENABLED(CONFIG_ZMK_HID_CONSUMER_REPORT_USAGES_FULL)
    HID_LOGICAL_MIN8(0x00),
    HID_LOGICAL_MAX16(0xFF, 0x0F),
    HID_USAGE_MIN8(0x00),
    HID_USAGE_MAX16(0xFF, 0x0F),
    HID_REPORT_SIZE(0x10),
#else
#error "A proper consumer HID report usage range must be selected"
#endif
    HID_REPORT_COUNT(CONFIG_ZMK_HID_CONSUMER_REPORT_SIZE),
    HID_INPUT(ZMK_HID_MAIN_VAL_DATA | ZMK_HID_MAIN_VAL_ARRAY | ZMK_HID_MAIN_VAL_ABS),
    HID_END_COLLECTION,
};

// struct zmk_hid_boot_report
// {
//     uint8_t modifiers;
//     uint8_t _unused;
//     uint8_t keys[6];
// } __packed;

struct zmk_hid_keyboard_report_body {
    zmk_mod_flags_t modifiers;
    uint8_t _reserved;
#if IS_ENABLED(CONFIG_ZMK_HID_REPORT_TYPE_NKRO)
    uint8_t keys[(ZMK_HID_KEYBOARD_NKRO_MAX_USAGE + 1) / 8];
#elif IS_ENABLED(CONFIG_ZMK_HID_REPORT_TYPE_HKRO)
    uint8_t keys[CONFIG_ZMK_HID_KEYBOARD_REPORT_SIZE];
#endif
} __packed;

struct zmk_hid_keyboard_report {
    uint8_t report_id;
    struct zmk_hid_keyboard_report_body body;
} __packed;

struct zmk_hid_consumer_report_body {
#if IS_ENABLED(CONFIG_ZMK_HID_CONSUMER_REPORT_USAGES_BASIC)
    uint8_t keys[CONFIG_ZMK_HID_CONSUMER_REPORT_SIZE];
#elif IS_ENABLED(CONFIG_ZMK_HID_CONSUMER_REPORT_USAGES_FULL)
    uint16_t keys[CONFIG_ZMK_HID_CONSUMER_REPORT_SIZE];
#endif
} __packed;

struct zmk_hid_consumer_report {
    uint8_t report_id;
    struct zmk_hid_consumer_report_body body;
} __packed;

zmk_mod_flags_t zmk_hid_get_explicit_mods();
int zmk_hid_register_mod(zmk_mod_t modifier);
int zmk_hid_unregister_mod(zmk_mod_t modifier);
bool zmk_hid_mod_is_pressed(zmk_mod_t modifier);

int zmk_hid_register_mods(zmk_mod_flags_t explicit_modifiers);
int zmk_hid_unregister_mods(zmk_mod_flags_t explicit_modifiers);
int zmk_hid_implicit_modifiers_press(zmk_mod_flags_t implicit_modifiers);
int zmk_hid_implicit_modifiers_release();
int zmk_hid_masked_modifiers_set(zmk_mod_flags_t masked_modifiers);
int zmk_hid_masked_modifiers_clear();

int zmk_hid_keyboard_press(zmk_key_t key);
int zmk_hid_keyboard_release(zmk_key_t key);
void zmk_hid_keyboard_clear();
bool zmk_hid_keyboard_is_pressed(zmk_key_t key);

int zmk_hid_consumer_press(zmk_key_t key);
int zmk_hid_consumer_release(zmk_key_t key);
void zmk_hid_consumer_clear();
bool zmk_hid_consumer_is_pressed(zmk_key_t key);

int zmk_hid_press(uint32_t usage);
int zmk_hid_release(uint32_t usage);
bool zmk_hid_is_pressed(uint32_t usage);

struct zmk_hid_keyboard_report *zmk_hid_get_keyboard_report();
struct zmk_hid_consumer_report *zmk_hid_get_consumer_report();