File content as of revision 0:cfd70fa91663:

#include "mbed.h"

#include "HIDServiceBase.h"

enum ButtonState
{
    BUTTON_UP,
    BUTTON_DOWN
};

enum JoystickButton
{
    JOYSTICK_BUTTON_1       = 0x1,
    JOYSTICK_BUTTON_2       = 0x2,
};

report_map_t JOYSTICK_REPORT_MAP = {
    USAGE_PAGE(1),      0x01,         // Generic Desktop
    USAGE(1),           0x04,         // Joystick
    COLLECTION(1),      0x01,         // Application
    COLLECTION(1),      0x00,         //  Physical
    USAGE_PAGE(1),      0x09,         //   Buttons
    USAGE_MINIMUM(1),   0x01,
    USAGE_MAXIMUM(1),   0x03,
    LOGICAL_MINIMUM(1), 0x00,
    LOGICAL_MAXIMUM(1), 0x01,
    REPORT_COUNT(1),    0x03,         //   2 bits (Buttons)
    REPORT_SIZE(1),     0x01,
    INPUT(1),           0x02,         //   Data, Variable, Absolute
    REPORT_COUNT(1),    0x01,         //   6 bits (Padding)
    REPORT_SIZE(1),     0x05,
    INPUT(1),           0x01,         //   Constant
    USAGE_PAGE(1),      0x01,         //   Generic Desktop
    USAGE(1),           0x30,         //   X
    USAGE(1),           0x31,         //   Y
    USAGE(1),           0x32,         //   Z
    USAGE(1),           0x33,         //   Rx
    LOGICAL_MINIMUM(1), 0x81,         //   -127
    LOGICAL_MAXIMUM(1), 0x7f,         //   127
    REPORT_SIZE(1),     0x08,         //   Three bytes
    REPORT_COUNT(1),    0x04,
    INPUT(1),           0x02,         //   Data, Variable, Absolute (unlike mouse)
    END_COLLECTION(0),
    END_COLLECTION(0),
};

uint8_t report[] = { 0, 0, 0, 0, 0 };

class JoystickService: public HIDServiceBase
{
public:
    JoystickService(BLE &_ble) :
        HIDServiceBase(_ble,
                       JOYSTICK_REPORT_MAP, sizeof(JOYSTICK_REPORT_MAP),
                       inputReport          = report,
                       outputReport         = NULL,
                       featureReport        = NULL,
                       inputReportLength    = sizeof(inputReport),
                       outputReportLength   = 0,
                       featureReportLength  = 0,
                       reportTickerDelay    = 20),
        buttonsState (0),
        failedReports (0)
    {
        speed[0] = 0;
        speed[1] = 0;
        speed[2] = 0;
        speed[3] = 0;

        startReportTicker();
    }

    int setSpeed(int8_t x, int8_t y, int8_t z)
    {
        speed[0] = x;
        speed[1] = y;
        speed[2] = z;

        return 0;
    }

    int setButton(JoystickButton button, ButtonState state)
    {
        if (state == BUTTON_UP)
            buttonsState &= ~(button);
        else
            buttonsState |= button;

        return 0;
    }

    virtual void sendCallback(void) {
        if (!connected)
            return;

        report[0] = buttonsState & 0x7;
        report[1] = speed[0];
        report[2] = speed[1];
        report[3] = speed[2];
        report[4] = speed[3];

        if (send(report))
            failedReports++;
    }

protected:
    uint8_t buttonsState;
    uint8_t speed[4];

public:
    uint32_t failedReports;
};