libusbdev/inc/usb_hid.h

/* This file is the part of the Lightweight USB device Stack for STM32 microcontrollers
 *
 * Copyright ©2016 Dmitry Filimonchuk <dmitrystu[at]gmail[dot]com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *   http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef _USB_HID_H_
#define _USB_HID_H_
#ifdef __cplusplus
    extern "C" {
#endif


/**\addtogroup USB_HID USB HID class
 * \brief This module contains USB Human Interface Devices class definitions
 * \details This module based on
 * + [Device Class Definition for Human Interface Devices (HID) Version 1.11](https://www.usb.org/sites/default/files/documents/hid1_11.pdf)
 * + [LUFA - the Lightweight USB Framework for AVRs.](https://github.com/abcminiuser/lufa)
 *
 * \par Control usage types
 *                Type     | Logical min | Logical max |                     Flags | Signal | Operation
 *-------------------------|-------------|-------------|---------------------------|--------|----------------
 *[LC] Linear control      | -1          | 1           | Relative, Preferred state |   Edge | Inc / Dec value
 *                        || -Min        | Max         | Relative, Preferred state |  Level | Inc / Dec value by n
 *                        ||  Min        | Max         | Absolute, Preferred state |   N/A  | Absolute value
 *[OOC] ON/OFF control     | -1          | 1           | Relative, No preferred    |   Edge | 1 asserts ON; -1 assertsOFF
 *                        || 0           | 1           | Relative, Preferred state |   Edge | 0->1 toggles ON/OFF
 *                        || 0           | 1           | Absolute, No preferred    |  Level | 0 asserts ON; 1 asserts OFF
 *[MC] Momentary control   | 0           | 1           | Absolute, Preferred state |  Level | 0 asserts, 1 deasserts condition
 *[OSC] One shot control   | 0           | 1           | Relative, Preferred state |   Edge | 0->1 triggers an event
 *[RTC] Re-trigger control | 0           | 1           | Absolute, Preferred state |  Level | 1 trigger an event
 *
 *\par Data usage types
 *Type               | Flgs                         | Description
 *-------------------|------------------------------|------------------------
 *[SEL] Selector     | Array                        | Contained a Named Array
 *[SV] Static value  | Constant, Variable, Absolute | Read-only multiple-bit value
 *[SF] Static flag   | Constant, Variable, Absolute | Read-only single-bit value
 *[DV] Dynamic value | Data, Variable, Absolute     | Read-write multiple-bit value
 *[DF] Dynamic flag  | Data, Variable, Absolute     | Read-write single-bit value
 *
 * @{ */

/**\name USB HID class code */
#define USB_CLASS_HID               0x03    /**<\brief Interface belongs to the Human Interface device class.*/

/**\name USB HID subclass codes
 * @{ */
#define USB_HID_SUBCLASS_NONBOOT    0x00    /**<\brief Nonboot subclass.*/
#define USB_HID_SUBCLASS_BOOT       0x01    /**<\brief Boot subclass.*/
/** @} */

/**\name USB HID protocol codes
 * @{ */
#define USB_HID_PROTO_NONBOOT       0x00    /**<\brief Nonboot protocol.*/
#define USB_HID_PROTO_KEYBOARD      0x01    /**<\brief Keyboard boot protocol.*/
#define USB_HID_PROTO_MOUSE         0x02    /**<\brief Mouse boot protocol.*/
/** @} */

#define USB_HID_REPORT_IN           0x00    /**<\brief Indicates that the item is an IN report type.*/
#define USB_HID_REPORT_OUT          0x01    /**<\brief Indicates that the item is an OUT report type.*/
#define USB_HID_REPORT_FEATURE      0x02    /**<\brief Indicates that the item is a FEATURE report type.*/


/**\name USB HID class-specified requests
 * @{ */
#define USB_HID_GETREPORT           0x01    /**<\brief Request to get the current HID report from the device.*/
#define USB_HID_GETIDLE             0x02    /**<\brief Request to get the current device idle count.*/
#define USB_HID_GETPROTOCOL         0x03    /**<\brief Request to get the current HID report protocol mode.*/
#define USB_HID_SETREPORT           0x09    /**<\brief Request to set the current HID report to the device.*/
#define USB_HID_SETIDLE             0x0A    /**<\brief Request to set the device's idle count.*/
#define USB_HID_SETPROTOCOL         0x0B    /**<\brief Request to set the current HID report protocol mode.*/
/** @} */

/**\name USB HID class-specified descriptor types
 * @{ */
#define USB_DTYPE_HID               0x21    /**<\brief HID class HID descriptor type.*/
#define USB_DTYPE_HID_REPORT        0x22    /**<\brief HID class HID report descriptor type.*/
/** @} */

/**\name USB HID country codes
 * @{ */
#define USB_HID_COUNTRY_NONE        0       /**<\brief Not supported */
#define USB_HID_COUNTRY_AR          1       /**<\brief Arabic */
#define USB_HID_COUNTRY_BE          2       /**<\brief Belgian */
#define USB_HID_COUNTRY_CA_BI       3       /**<\brief Canadian-Bilingual */
#define USB_HID_COUNTRY_CA_FR       4       /**<\brief Canadian-French */
#define USB_HID_COUNTRY_CZ          5       /**<\brief Czech Republic */
#define USB_HID_COUNTRY_DK          6       /**<\brief Danish */
#define USB_HID_COUNTRY_FI          7       /**<\brief Finnish */
#define USB_HID_COUNTRY_FR          8       /**<\brief French */
#define USB_HID_COUNTRY_DE          9       /**<\brief German */
#define USB_HID_COUNTRY_GR          10      /**<\brief Greek */
#define USB_HID_COUNTRY_HEB         11      /**<\brief Hebrew */
#define USB_HID_COUNTRY_HU          12      /**<\brief Hungary */
#define USB_HID_COUNTRY_ISO         13      /**<\brief International (ISO) */
#define USB_HID_COUNTRY_IT          14      /**<\brief Italian */
#define USB_HID_COUNTRY_JP          15      /**<\brief Japan (Katakana) */
#define USB_HID_COUNTRY_KR          16      /**<\brief Korean */
#define USB_HID_COUNTRY_LAT         17      /**<\brief Latin American */
#define USB_HID_COUNTRY_NL          18      /**<\brief Netherlands/Dutch */
#define USB_HID_COUNTRY_NO          19      /**<\brief Norwegian */
#define USB_HID_COUNTRY_PER         20      /**<\brief Persian (Farsi) */
#define USB_HID_COUNTRY_PL          21      /**<\brief Poland */
#define USB_HID_COUNTRY_PO          22      /**<\brief Portuguese */
#define USB_HID_COUNTRY_RU          23      /**<\brief Russia */
#define USB_HID_COUNTRY_SK          24      /**<\brief Slovakia */
#define USB_HID_COUNTRY_ES          25      /**<\brief Spanish */
#define USB_HID_COUNTRY_SE          26      /**<\brief Swedish */
#define USB_HID_COUNTRY_CH_FR       26      /**<\brief Swiss-French */
#define USB_HID_COUNTRY_CH_DE       27      /**<\brief Swiss-German */
#define USB_HID_COUNTRY_CH          29      /**<\brief Switzerland */
#define USB_HID_COUNTRY_TW          30      /**<\brief Taiwan */
#define USB_HID_COUNTRY_TR_Q        31      /**<\brief Turkish-Q */
#define USB_HID_COUNTRY_UK          32      /**<\brief United Kingdom */
#define USB_HID_COUNTRY_US          33      /**<\brief United States */
#define USB_HID_COUNTRY_YU          34      /**<\brief Yugoslavia */
#define USB_HID_COUNTRY_TR_F        35      /**<\brief Turkish-F */
/** @} */

/**\name HID Collections types
 * @{ */
#define HID_PHYSICAL_COLLECTION             0x00    /**<\brief A physical collection of items.*/
#define HID_APPLICATION_COLLECTION          0x01    /**<\brief Applies a name to a top level collection which the operating
                                                     * system uses to identify a device and possibly remap to a legacy API.*/
#define HID_LOGICAL_COLLECTION              0x02    /**<\brief A logical collection of items.*/
#define HID_REPORT_COLLECTION               0x03
#define HID_NARY_COLLECTION                 0x04    /**<\brief A collection that encompasses an array definition, naming
                                                     * the array set or the field created by the array.*/
#define HID_USAGE_SWITCH_COLLECTION         0x05    /**<\brief Modifies the purpose or function of the usages (controls) that it contains. */
#define HID_USAGE_MODIFIER_COLLECTION       0x06    /**<\brief Modifies the purpose or function of the usages (controls) that contains it.*/
/** @} */


/**\brief USB HID functional descriptor */
struct usb_hid_descriptor {
    uint8_t     bLength;            /**<\brief Size of the descriptor, in bytes. */
    uint8_t     bDescriptorType;    /**<\brief Type of the descriptor, set to \ref USB_DTYPE_HID */
    uint16_t    bcdHID;             /**<\brief BCD encoded version that the HID descriptor and device complies to. */
    uint8_t     bCountryCode;       /**<\brief Country code of the localized device, or zero if universal. */
    uint8_t     bNumDescriptors;    /**<\brief Total number of HID report descriptors for the interface. */
    uint8_t     bDescriptorType0;   /**<\brief 1'st HID report descriptor type, set to \ref USB_DTYPE_HID_REPORT */
    uint16_t    wDescriptorLength0; /**<\brief 1'sr HID report descriptor length in bytes. */
} __attribute__((packed));

/**\brief USB HID functional descriptor header */
struct usb_hid_descriptor_header {
    uint8_t     bLength;            /**<\brief Size of the descriptor, in bytes. */
    uint8_t     bDescriptorType;    /**<\brief Type of the descriptor, set to \ref USB_DTYPE_HID */
    uint16_t    bcdHID;             /**<\brief BCD encoded version that the HID descriptor and device complies to. */
    uint8_t     bCountryCode;       /**<\brief Country code of the localized device, or zero if universal. */
    uint8_t     bNumDescriptors;    /**<\brief Total number of HID report descriptors for the interface. */
} __attribute__((packed));

/**\brief USB HID report descriptor */
struct usb_hid_report_descriptor {
    uint8_t     bDescriptorType;   /**<\brief Type of HID report, set to \ref USB_DTYPE_HID_REPORT */
    uint16_t    wDescriptorLength; /**<\brief Length of the associated HID report descriptor, in bytes. */
} __attribute__((packed));

/**\brief Helper macro for the multireport hid descriptor */
#define DECLARE_USB_HID_DESCRIPTOR(p)               \
struct usb_hid_descriptor_##p {                     \
    uint8_t     bLength;                            \
    uint8_t     bDescriptorType;                    \
    uint16_t    bcdHID;                             \
    uint8_t     bCountryCode;                       \
    uint8_t     bNumDescriptors;                    \
    struct usb_hid_report_descriptor report[p];     \
} __attribute__((packed));


/* Private Interface - For use in library only: */
#if !defined(__DOXYGEN__)
    /* Macros: */
    #define CONCAT(x, y)            x ## y
    #define CONCAT_EXPANDED(x, y)   CONCAT(x, y)
    #define HID_RI_DATA_SIZE_MASK                   0x03
    #define HID_RI_TYPE_MASK                        0x0C
    #define HID_RI_TAG_MASK                         0xF0
    #define HID_RI_TYPE_MAIN                        0x00
    #define HID_RI_TYPE_GLOBAL                      0x04
    #define HID_RI_TYPE_LOCAL                       0x08
    #define HID_RI_DATA_BITS_0                      0x00
    #define HID_RI_DATA_BITS_8                      0x01
    #define HID_RI_DATA_BITS_16                     0x02
    #define HID_RI_DATA_BITS_32                     0x03
    #define HID_RI_DATA_BITS(DataBits)              CONCAT_EXPANDED(HID_RI_DATA_BITS_, DataBits)
    #define _HID_RI_ENCODE_0(Data)
    #define _HID_RI_ENCODE_8(Data)                  , (Data & 0xFF)
    #define _HID_RI_ENCODE_16(Data)                 _HID_RI_ENCODE_8(Data)  _HID_RI_ENCODE_8(Data >> 8)
    #define _HID_RI_ENCODE_32(Data)                 _HID_RI_ENCODE_16(Data) _HID_RI_ENCODE_16(Data >> 16)
    #define _HID_RI_ENCODE(DataBits, ...)           CONCAT_EXPANDED(_HID_RI_ENCODE_, DataBits(__VA_ARGS__))
    #define _HID_RI_ENTRY(Type, Tag, DataBits, ...) (Type | Tag | HID_RI_DATA_BITS(DataBits)) _HID_RI_ENCODE(DataBits, (__VA_ARGS__))
#endif
/* Public Interface - May be used in end-application: */
/* Macros: */
/** \name HID Input, Output and Feature Report Descriptor Item Flags */
//@{
#define HID_IOF_CONSTANT                        (1 << 0)
#define HID_IOF_DATA                            (0 << 0)
#define HID_IOF_VARIABLE                        (1 << 1)
#define HID_IOF_ARRAY                           (0 << 1)
#define HID_IOF_RELATIVE                        (1 << 2)
#define HID_IOF_ABSOLUTE                        (0 << 2)
#define HID_IOF_WRAP                            (1 << 3)
#define HID_IOF_NO_WRAP                         (0 << 3)
#define HID_IOF_NON_LINEAR                      (1 << 4)
#define HID_IOF_LINEAR                          (0 << 4)
#define HID_IOF_NO_PREFERRED_STATE              (1 << 5)
#define HID_IOF_PREFERRED_STATE                 (0 << 5)
#define HID_IOF_NULLSTATE                       (1 << 6)
#define HID_IOF_NO_NULL_POSITION                (0 << 6)
#define HID_IOF_VOLATILE                        (1 << 7)
#define HID_IOF_NON_VOLATILE                    (0 << 7)
#define HID_IOF_BUFFERED_BYTES                  (1 << 8)
#define HID_IOF_BITFIELD                        (0 << 8)
//@}

/** \name HID Report Descriptor Item Macros */
//@{
#define HID_RI_INPUT(DataBits, ...)             _HID_RI_ENTRY(HID_RI_TYPE_MAIN  , 0x80, DataBits, __VA_ARGS__)
#define HID_RI_OUTPUT(DataBits, ...)            _HID_RI_ENTRY(HID_RI_TYPE_MAIN  , 0x90, DataBits, __VA_ARGS__)
#define HID_RI_COLLECTION(DataBits, ...)        _HID_RI_ENTRY(HID_RI_TYPE_MAIN  , 0xA0, DataBits, __VA_ARGS__)
#define HID_RI_FEATURE(DataBits, ...)           _HID_RI_ENTRY(HID_RI_TYPE_MAIN  , 0xB0, DataBits, __VA_ARGS__)
#define HID_RI_END_COLLECTION(DataBits, ...)    _HID_RI_ENTRY(HID_RI_TYPE_MAIN  , 0xC0, DataBits, __VA_ARGS__)
#define HID_RI_USAGE_PAGE(DataBits, ...)        _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x00, DataBits, __VA_ARGS__)
#define HID_RI_LOGICAL_MINIMUM(DataBits, ...)   _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x10, DataBits, __VA_ARGS__)
#define HID_RI_LOGICAL_MAXIMUM(DataBits, ...)   _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x20, DataBits, __VA_ARGS__)
#define HID_RI_PHYSICAL_MINIMUM(DataBits, ...)  _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x30, DataBits, __VA_ARGS__)
#define HID_RI_PHYSICAL_MAXIMUM(DataBits, ...)  _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x40, DataBits, __VA_ARGS__)
#define HID_RI_UNIT_EXPONENT(DataBits, ...)     _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x50, DataBits, __VA_ARGS__)
#define HID_RI_UNIT(DataBits, ...)              _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x60, DataBits, __VA_ARGS__)
#define HID_RI_REPORT_SIZE(DataBits, ...)       _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x70, DataBits, __VA_ARGS__)
#define HID_RI_REPORT_ID(DataBits, ...)         _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x80, DataBits, __VA_ARGS__)
#define HID_RI_REPORT_COUNT(DataBits, ...)      _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0x90, DataBits, __VA_ARGS__)
#define HID_RI_PUSH(DataBits, ...)              _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0xA0, DataBits, __VA_ARGS__)
#define HID_RI_POP(DataBits, ...)               _HID_RI_ENTRY(HID_RI_TYPE_GLOBAL, 0xB0, DataBits, __VA_ARGS__)
#define HID_RI_USAGE(DataBits, ...)             _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x00, DataBits, __VA_ARGS__)
#define HID_RI_USAGE_MINIMUM(DataBits, ...)     _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x10, DataBits, __VA_ARGS__)
#define HID_RI_USAGE_MAXIMUM(DataBits, ...)     _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x20, DataBits, __VA_ARGS__)
#define HID_RI_DESIGNATOR_INDEX(DataBits, ...)  _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x30, DataBits, __VA_ARGS__)
#define HID_RI_DESIGNATOR_MIN(DataBits, ...)    _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x40, DataBits, __VA_ARGS__)
#define HID_RI_DESIGNATOR_MAX(DataBits, ...)    _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x50, DataBits, __VA_ARGS__)
#define HID_RI_STRING_INDEX(DataBits, ...)      _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x70, DataBits, __VA_ARGS__)
#define HID_RI_STRING_MINIMUM(DataBits, ...)    _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x80, DataBits, __VA_ARGS__)
#define HID_RI_STRING_MAXIMUM(DataBits, ...)    _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0x90, DataBits, __VA_ARGS__)
#define HID_RI_DELIMITER(DataBits, ...)         _HID_RI_ENTRY(HID_RI_TYPE_LOCAL , 0xA0, DataBits, __VA_ARGS__)

#define HID_INPUT(data)                     HID_RI_INPUT(8, data)
#define HID_OUTPUT(data)                    HID_RI_OUTPUT(8, data)
#define HID_COLLECTION(data)                HID_RI_COLLECTION(8, data)
#define HID_FEATURE(data)                   HID_RI_FEATURE(8, data)
#define HID_END_COLLECTION                  HID_RI_END_COLLECTION(0)
#define HID_USAGE_PAGE(data)                HID_RI_USAGE_PAGE(8, data)
#define HID_LOGICAL_MINIMUM(data)           HID_RI_LOGICAL_MINIMUM(8, data)
#define HID_LOGICAL_MAXIMUM(data)           HID_RI_LOGICAL_MAXIMUM(8, data)
#define HID_PHYSICAL_MINIMUM(data)          HID_RI_PHYSICAL_MINIMUM(8, data)
#define HID_PHYSICAL_MAXIMUM(data)          HID_RI_PHYSICAL_MAXIMUM(8, data)
#define HID_UNIT_EXPONENT(data)             HID_RI_UNIT_EXPONENT(8, data)
#define HID_UNIT(bits, data)                HID_RI_UNIT(bits, data)
#define HID_REPORT_SIZE(data)               HID_RI_REPORT_SIZE(8, data)
#define HID_REPORT_ID(data)                 HID_RI_REPORT_ID(8, data)
#define HID_REPORT_COUNT(data)              HID_RI_REPORT_COUNT(8, data)
#define HID_PUSH                            HID_RI_PUSH(0)
#define HID_POP                             HID_RI_POP(0)
#define HID_USAGE(data)                     HID_RI_USAGE(8, data)
#define HID_USAGE_MINIMUM(data)             HID_RI_USAGE_MINIMUM(8, data)
#define HID_USAGE_MAXIMUM(data)             HID_RI_USAGE_MAXIMUM(8, data)
//@}

/**\name Macros for the units encoding */
//@{
#define HID_UNIT_NONE                       0x00                    /**<No system. */
#define HID_UNIT_CGS_LINEAR                 0x01                    /**<Centimeter-Gram-Second metric linear system.*/
#define HID_UNIT_CGS_ROTATION               0x02                    /**<Centimeter-Gram-Second metric rotation system.*/
#define HID_UNIT_IMPERIAL_LINEAR            0x03                    /**<Imperial linear system.*/
#define HID_UNIT_IMPERIAL_ROTATION          0x04                    /**<Imperial rotation system.*/
#define HID_UNIT_LENGTH(exp)                ((exp & 0x0F) << 4)     /**<Length, position, distance unit. cm (CGS), inch (Imperial) */
#define HID_UNIT_ANGLE(exp)                 ((exp & 0x0F) << 4)     /**<Angle unit. radians(CGS), degree (Imperial) */
#define HID_UNIT_MASS(exp)                  ((exp & 0x0F) << 8)     /**<Mass unit. gram (CGS), slug (Imperial) */
#define HID_UNIT_TIME(exp)                  ((exp & 0x0F) << 12)    /**<Time unit. secound. */
#define HID_UNIT_TEMPERATURE(exp)           ((exp & 0x0F) << 16)    /**<Temperature unit. Kelvin (CGS), Fahrenheit (Imperial) */
#define HID_UNIT_CURRENT(exp)               ((exp & 0x0F) << 20)    /**<Current unit. Ampere */
#define HID_UNIT_LUMINOUS(exp)              ((exp & 0x0F) << 24)    /**<Luminous intensity unit. Candela */
//@}

/**\name Macros for the some SI named units */
//@{
/** SI length. m = 1E2 * cm */
#define HID_UNIT_METER(exp) \
    HID_UNIT(8, HID_UNIT_CGS_LINEAR | HID_UNIT_LENGTH(1)), \
    HID_UNIT_EXPONENT(exp + 2)
/** SI mass. kg = 1E3 * g */
#define HID_UNIT_KG(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1), \
    HID_UNIT_EXPONENT(exp + 3)
/** SI time. 1s */
#define HID_UNIT_SECOND(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_TIME(1), \
    HID_UNIT_EXPONENT(exp + 0)
/** SI velocity. m/s = 1E2 * cm/s */
#define HID_UNIT_MPS(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_LENGTH(1) | HID_UNIT_TIME(-1)), \
    HID_UNIT_EXPONENT(exp + 2)
/** SI acceleration. m/s^2 = 1E2 * cm/s^2*/
#define HID_UNIT_MPS2(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_LENGTH(1) | HID_UNIT_TIME(-2)), \
    HID_UNIT_EXPONENT(exp + 2)
/** SI force. N = 1E5 * g * cm / s^2 */
#define HID_UNIT_NEWTON(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(1) | HID_UNIT_TIME(-2)), \
    HID_UNIT_EXPONENT(exp + 5)
/** SI energy. J = 1E7 * g * cm^2 / s^2 */
#define HID_UNIT_JOULE(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(2) | HID_UNIT_TIME(-2)), \
    HID_UNIT_EXPONENT(exp + 7)
/** SI power. W = 1E7 * g * cm^2 / s^3 */
#define HID_UNIT_WATT(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(2) | HID_UNIT_TIME(-3)), \
    HID_UNIT_EXPONENT(exp + 7)
/** SI pressure. Pa = 1E1 * g / (cm * s^2) */
#define HID_UNIT_PASCAL(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(-1) | HID_UNIT_TIME(-2)), \
    HID_UNIT_EXPONENT(exp + 1)
/** SI frequency. Hz = 1 / s */
#define HID_UNIT_HERTZ(exp) \
    HID_UNIT(16, HID_UNIT_CGS_LINEAR | HID_UNIT_TIME(-1)), \
    HID_UNIT_EXPONENT(exp + 0)
/** SI current. A */
#define HID_UNIT_AMPERE(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_CURRENT(1)), \
    HID_UNIT_EXPONENT(exp)
/** SI voltage. V = W / A  = 1E7 * g * cm^2 / (s^3 * A) */
#define HID_UNIT_VOLT(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(2) |  HID_UNIT_TIME(-3) | HID_UNIT_CURRENT(-1)), \
    HID_UNIT_EXPONENT(exp + 7)
/** SI resistance. Ohm = 1E7 * g * cm^2 / (s^3 * A^2) */
#define HID_UNIT_OHM(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(2) |  HID_UNIT_TIME(-3) | HID_UNIT_CURRENT(-2)), \
    HID_UNIT_EXPONENT(exp + 7)
/** SI inductance. H = 1E7 * g * cm^2 / (s^2 * A^2) */
#define HID_UNIT_HENRY(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_LENGTH(2) |  HID_UNIT_TIME(-2) | HID_UNIT_CURRENT(-2)), \
    HID_UNIT_EXPONENT(exp + 7)
/** SI  capacitance. F = 1E-7 * s^4 * A^2 / (cm^2 * g) */
#define HID_UNIT_FARAD(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(-1) | HID_UNIT_LENGTH(-2) |  HID_UNIT_TIME(4) | HID_UNIT_CURRENT(2)), \
    HID_UNIT_EXPONENT(exp - 7)
/** SI  electric charge. C = s * A */
#define HID_UNIT_COULOMB(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_TIME(1) | HID_UNIT_CURRENT(1)), \
    HID_UNIT_EXPONENT(exp)
/** SI  magnetic flux density. T = 1E3 * g / (s^2 * A) */
#define HID_UNIT_TESLA(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_MASS(1) | HID_UNIT_TIME(-2) | HID_UNIT_CURRENT(-1)), \
    HID_UNIT_EXPONENT(exp)
/** SI  illuminance. lx = 1E4 * cd / cm^2 */
#define HID_UNIT_LUX(exp) \
    HID_UNIT(32, HID_UNIT_CGS_LINEAR | HID_UNIT_LENGTH(-1) | HID_UNIT_LUMINOUS(1)), \
    HID_UNIT_EXPONENT(exp)

//@}

/** @}  */

#ifdef __cplusplus
    }
#endif

#endif