unleashed-firmware/firmware/targets/f7/furi-hal/furi-hal-bt-hid.c

#include "furi-hal-bt-hid.h"
#include "dev_info_service.h"
#include "battery_service.h"
#include "hid_service.h"

#include <furi.h>

#define FURI_HAL_BT_INFO_BASE_USB_SPECIFICATION (0x0101)
#define FURI_HAL_BT_INFO_COUNTRY_CODE (0x00)
#define FURI_HAL_BT_HID_INFO_FLAG_REMOTE_WAKE_MSK (0x01)
#define FURI_HAL_BT_HID_INFO_FLAG_NORMALLY_CONNECTABLE_MSK (0x02)

#define FURI_HAL_BT_HID_KB_KEYS_MAX (6)

typedef struct {
    uint8_t mods;
    uint8_t reserved;
    uint8_t key[FURI_HAL_BT_HID_KB_KEYS_MAX];
} FuriHalBtHidKbReport;

// TODO rework with HID defines
static uint8_t furi_hal_bt_hid_report_map_data[] = {
    0x05, 0x01,       // Usage Page (Generic Desktop)
    0x09, 0x06,       // Usage (Keyboard)
    0xA1, 0x01,       // Collection (Application)
    0x05, 0x07,       // Usage Page (Key Codes)
    0x19, 0xe0,       // Usage Minimum (224)
    0x29, 0xe7,       // Usage Maximum (231)
    0x15, 0x00,       // Logical Minimum (0)
    0x25, 0x01,       // Logical Maximum (1)
    0x75, 0x01,       // Report Size (1)
    0x95, 0x08,       // Report Count (8)
    0x81, 0x02,       // Input (Data, Variable, Absolute)

    0x95, 0x01,       // Report Count (1)
    0x75, 0x08,       // Report Size (8)
    0x81, 0x01,       // Input (Constant) reserved byte(1)

    0x95, 0x05,       // Report Count (5)
    0x75, 0x01,       // Report Size (1)
    0x05, 0x08,       // Usage Page (Page# for LEDs)
    0x19, 0x01,       // Usage Minimum (1)
    0x29, 0x05,       // Usage Maximum (5)
    0x91, 0x02,       // Output (Data, Variable, Absolute), Led report
    0x95, 0x01,       // Report Count (1)
    0x75, 0x03,       // Report Size (3)
    0x91, 0x01,       // Output (Data, Variable, Absolute), Led report padding

    0x95, 0x06,       // Report Count (6)
    0x75, 0x08,       // Report Size (8)
    0x15, 0x00,       // Logical Minimum (0)
    0x25, 0x65,       // Logical Maximum (101)
    0x05, 0x07,       // Usage Page (Key codes)
    0x19, 0x00,       // Usage Minimum (0)
    0x29, 0x65,       // Usage Maximum (101)
    0x81, 0x00,       // Input (Data, Array) Key array(6 bytes)

    0x09, 0x05,       // Usage (Vendor Defined)
    0x15, 0x00,       // Logical Minimum (0)
    0x26, 0xFF, 0x00, // Logical Maximum (255)
    0x75, 0x08,       // Report Size (8 bit)
    0x95, 0x02,       // Report Count (2)
    0xB1, 0x02,       // Feature (Data, Variable, Absolute)

    0xC0              // End Collection (Application)
};

FuriHalBtHidKbReport* kb_report = NULL;

void furi_hal_bt_hid_start() {
    // Start device info
    if(!dev_info_svc_is_started()) {
        dev_info_svc_start();
    }
    // Start battery service
    if(!battery_svc_is_started()) {
        battery_svc_start();
    }
    // Start HID service
    if(!hid_svc_is_started()) {
        hid_svc_start();
    }
    // Configure HID Keyboard
    kb_report = furi_alloc(sizeof(FuriHalBtHidKbReport));
    // Configure Report Map characteristic
    hid_svc_update_report_map(furi_hal_bt_hid_report_map_data, sizeof(furi_hal_bt_hid_report_map_data));
    // Configure HID Information characteristic
    uint8_t hid_info_val[4] = {
        FURI_HAL_BT_INFO_BASE_USB_SPECIFICATION & 0x00ff,
        (FURI_HAL_BT_INFO_BASE_USB_SPECIFICATION & 0xff00) >> 8,
        FURI_HAL_BT_INFO_COUNTRY_CODE,
        FURI_HAL_BT_HID_INFO_FLAG_REMOTE_WAKE_MSK | FURI_HAL_BT_HID_INFO_FLAG_NORMALLY_CONNECTABLE_MSK,
    };
    hid_svc_update_info(hid_info_val, sizeof(hid_info_val));
}

void furi_hal_bt_hid_stop() {
    furi_assert(kb_report);
    // Stop all services
    if(dev_info_svc_is_started()) {
        dev_info_svc_stop();
    }
    if(battery_svc_is_started()) {
        battery_svc_stop();
    }
    if(hid_svc_is_started()) {
        hid_svc_stop();
    }
    free(kb_report);
    kb_report = NULL;
}

bool furi_hal_bt_hid_kb_press(uint16_t button) {
    furi_assert(kb_report);
    for (uint8_t i = 0; i < FURI_HAL_BT_HID_KB_KEYS_MAX; i++) {
        if (kb_report->key[i] == 0) {
            kb_report->key[i] = button & 0xFF;
            break;
        }
    }
    kb_report->mods |= (button >> 8);
    return hid_svc_update_input_report((uint8_t*)kb_report, sizeof(FuriHalBtHidKbReport));
}

bool furi_hal_bt_hid_kb_release(uint16_t button) {
    furi_assert(kb_report);
    for (uint8_t i = 0; i < FURI_HAL_BT_HID_KB_KEYS_MAX; i++) {
        if (kb_report->key[i] == (button & 0xFF)) {
            kb_report->key[i] = 0;
            break;
        }
    }
    kb_report->mods &= ~(button >> 8);
    return hid_svc_update_input_report((uint8_t*)kb_report, sizeof(FuriHalBtHidKbReport));
}

bool furi_hal_bt_hid_kb_release_all() {
    furi_assert(kb_report);
    memset(kb_report, 0, sizeof(FuriHalBtHidKbReport));
    return hid_svc_update_input_report((uint8_t*)kb_report, sizeof(FuriHalBtHidKbReport));
}