subsys/usb/device/class/audio/usb_audio_internal.h - third_party/github/zephyrproject-rtos/zephyr - Git at Google

 /*
  * USB audio class internal header
  *
  * Copyright (c) 2020 Nordic Semiconductor ASA
  *
  * SPDX-License-Identifier: Apache-2.0
  */

 /**
  * @file
  * @brief USB Audio Device Class internal header
  *
  * This header file is used to store internal configuration
  * defines.
  */

 #ifndef ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_
 #define ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_

 #define DUMMY_API  (const void *)1

 #define USB_PASSIVE_IF_DESC_SIZE sizeof(struct usb_if_descriptor)
 #define USB_AC_CS_IF_DESC_SIZE sizeof(struct as_cs_interface_descriptor)
 #define USB_FORMAT_TYPE_I_DESC_SIZE sizeof(struct format_type_i_descriptor)
 #define USB_STD_AS_AD_EP_DESC_SIZE sizeof(struct std_as_ad_endpoint_descriptor)
 #define USB_CS_AS_AD_EP_DESC_SIZE sizeof(struct cs_as_ad_ep_descriptor)
 #define USB_ACTIVE_IF_DESC_SIZE (USB_PASSIVE_IF_DESC_SIZE + \
 				 USB_AC_CS_IF_DESC_SIZE + \
 				 USB_FORMAT_TYPE_I_DESC_SIZE + \
 				 USB_STD_AS_AD_EP_DESC_SIZE + \
 				 USB_CS_AS_AD_EP_DESC_SIZE)

 #define INPUT_TERMINAL_DESC_SIZE sizeof(struct input_terminal_descriptor)
 #define OUTPUT_TERMINAL_DESC_SIZE sizeof(struct output_terminal_descriptor)

 #define BMA_CONTROLS_OFFSET 6
 #define FU_FIXED_ELEMS_SIZE 7

 /* Macros for maintaining features of feature unit entity */
 #define FEATURE_MUTE_SIZE			0x01
 #define FEATURE_VOLUME_SIZE			0x02
 #define FEATURE_BASS_SIZE			0x01
 #define FEATURE_MID_SIZE			0x01
 #define FEATURE_TREBLE_SIZE			0x01
 #define FEATURE_TONE_CONTROL_SIZE (FEATURE_BASS_SIZE +\
 				   FEATURE_MID_SIZE + \
 				   FEATURE_TREBLE_SIZE)
 #define FEATURE_GRAPHIC_EQUALIZER_SIZE		0x01
 #define FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE	0x01
 #define FEATURE_DELAY_SIZE			0x02
 #define FEATURE_BASS_BOOST_SIZE			0x01
 #define FEATURE_LOUDNESS_SIZE			0x01

 #define POS_MUTE		   0
 #define POS_VOLUME		   (POS_MUTE + FEATURE_MUTE_SIZE)
 #define POS_BASS		   (POS_VOLUME + FEATURE_VOLUME_SIZE)
 #define POS_MID			   (POS_BASS + FEATURE_BASS_SIZE)
 #define POS_TREBLE		   (POS_MID + FEATURE_MID_SIZE)
 #define POS_GRAPHIC_EQUALIZER	   (POS_TREBLE + FEATURE_TREBLE_SIZE)
 #define POS_AUTOMATIC_GAIN_CONTROL (POS_GRAPHIC_EQUALIZER + \
 					FEATURE_GRAPHIC_EQUALIZER_SIZE)
 #define POS_DELAY		   (POS_AUTOMATIC_GAIN_CONTROL + \
 					FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE)
 #define POS_BASS_BOOST		   (POS_DELAY + FEATURE_DELAY_SIZE)
 #define POS_LOUDNESS		   (POS_BASS_BOOST + FEATURE_BASS_BOOST_SIZE)

 #define POS(prop, ch_idx, ch_cnt) (ch_cnt * POS_##prop + \
 				  (ch_idx * FEATURE_##prop##_SIZE))
 #define LEN(ch_cnt, prop) (ch_cnt * FEATURE_##prop##_SIZE)

 /* Names of compatibles used for configuration of the device */
 #define COMPAT_HP  usb_audio_hp
 #define COMPAT_MIC usb_audio_mic
 #define COMPAT_HS  usb_audio_hs

 #define HEADPHONES_DEVICE_COUNT  DT_NUM_INST_STATUS_OKAY(COMPAT_HP)
 #define MICROPHONE_DEVICE_COUNT  DT_NUM_INST_STATUS_OKAY(COMPAT_MIC)
 #define HEADSET_DEVICE_COUNT     DT_NUM_INST_STATUS_OKAY(COMPAT_HS)

 #define IF_USB_AUDIO_PROP_HP(i, prop, bitmask) \
 	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HP), prop), (bitmask), (0))
 #define IF_USB_AUDIO_PROP_MIC(i, prop, bitmask) \
 	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_MIC), prop), (bitmask), (0))
 #define IF_USB_AUDIO_PROP_HS_HP(i, prop, bitmask) \
 	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HS), hp_##prop), (bitmask), (0))
 #define IF_USB_AUDIO_PROP_HS_MIC(i, prop, bitmask) \
 	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HS), mic_##prop), (bitmask), (0))
 #define IF_USB_AUDIO_PROP(dev, i, prop, bitmask) \
 	IF_USB_AUDIO_PROP_##dev(i, prop, bitmask)

 /* Macro for getting the bitmask of configured channels for given device */
 #define CH_CFG(dev, i) (0x0000			 \
 | IF_USB_AUDIO_PROP(dev, i, channel_l,   BIT(0)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_r,   BIT(1)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_c,   BIT(2)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_lfe, BIT(3)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_ls,  BIT(4)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_rs,  BIT(5)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_lc,  BIT(6)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_rc,  BIT(7)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_s,   BIT(8)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_sl,  BIT(9)) \
 | IF_USB_AUDIO_PROP(dev, i, channel_sr,  BIT(10))\
 | IF_USB_AUDIO_PROP(dev, i, channel_t,   BIT(11))\
 )

 /* Macro for getting the number of configured channels for given device.
  * Master channel (0) excluded.
  */
 #define CH_CNT(dev, i) (0		   \
 + IF_USB_AUDIO_PROP(dev, i, channel_l,   1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_r,   1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_c,   1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_lfe, 1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_ls,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_rs,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_lc,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_rc,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_s,   1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_sl,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_sr,  1)\
 + IF_USB_AUDIO_PROP(dev, i, channel_t,   1)\
 )

 /* Macro for getting bitmask of supported features for given device */
 #define FEATURES(dev, i) (0x0000					    \
 | IF_USB_AUDIO_PROP(dev, i, feature_mute,		    BIT(0))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_volume,		    BIT(1))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_tone_control,  BIT(2) | BIT(3) | BIT(4))\
 | IF_USB_AUDIO_PROP(dev, i, feature_graphic_equalizer,	    BIT(5))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_automatic_gain_control, BIT(6))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_delay,		    BIT(7))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_bass_boost,		    BIT(8))	    \
 | IF_USB_AUDIO_PROP(dev, i, feature_loudness,		    BIT(9))	    \
 )

 /* Macro for getting required size to store values for supported features. */
 #define FEATURES_SIZE(dev, i) ((CH_CNT(dev, i) + 1) * (0x0000	\
 + IF_USB_AUDIO_PROP(dev, i, feature_mute,			\
 			    FEATURE_MUTE_SIZE)			\
 + IF_USB_AUDIO_PROP(dev, i, feature_volume,			\
 			    FEATURE_VOLUME_SIZE)		\
 + IF_USB_AUDIO_PROP(dev, i, feature_tone_control,		\
 			    FEATURE_TONE_CONTROL_SIZE)		\
 + IF_USB_AUDIO_PROP(dev, i, feature_graphic_equalizer,		\
 			    FEATURE_GRAPHIC_EQUALIZER_SIZE)	\
 + IF_USB_AUDIO_PROP(dev, i, feature_automatic_gain_control,	\
 			    FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE)\
 + IF_USB_AUDIO_PROP(dev, i, feature_delay,			\
 			    FEATURE_DELAY_SIZE)			\
 + IF_USB_AUDIO_PROP(dev, i, feature_bass_boost,			\
 			    FEATURE_BASS_BOOST_SIZE)		\
 + IF_USB_AUDIO_PROP(dev, i, feature_loudness,			\
 			    FEATURE_LOUDNESS_SIZE)		\
 ))

 #define GET_RES_HP(i) DT_PROP(DT_INST(i, COMPAT_HP), resolution)
 #define GET_RES_MIC(i) DT_PROP(DT_INST(i, COMPAT_MIC), resolution)
 #define GET_RES_HS_HP(i) DT_PROP(DT_INST(i, COMPAT_HS), hp_resolution)
 #define GET_RES_HS_MIC(i) DT_PROP(DT_INST(i, COMPAT_HS), mic_resolution)
 #define GET_RES(dev, i) GET_RES_##dev(i)

 #define SYNC_TYPE_HP(i)     3
 #define SYNC_TYPE_MIC(i)    DT_ENUM_IDX(DT_INST(i, COMPAT_MIC), sync_type)
 #define SYNC_TYPE_HS_HP(i)  3
 #define SYNC_TYPE_HS_MIC(i) DT_ENUM_IDX(DT_INST(i, COMPAT_HS), mic_sync_type)
 #define SYNC_TYPE(dev, i) (SYNC_TYPE_##dev(i) << 2)

 #define EP_SIZE(dev, i) \
 	((GET_RES(dev, i)/8) * CH_CNT(dev, i) * 48)

 /* *_ID() macros are used to give proper Id to each entity describing
  * the device. Entities Id must start from 1 that's why 1 is added.
  * Multiplication by 3 for HP/MIC comes from the fact that 3 entities are
  * required to describe the device, 6 in case of HS.
  */
 #define HP_ID(i) ((3*i) + 1)
 #define MIC_ID(i) ((3*(HEADPHONES_DEVICE_COUNT + i)) + 1)
 #define HS_ID(i) ((3*(HEADPHONES_DEVICE_COUNT + \
 		      MICROPHONE_DEVICE_COUNT)) + 6*i + 1)

 /* *_LINK() macros are used to properly connect relevant audio streaming
  * class specific interface with valid entity. In case of Headphones this
  * will always be 1st entity describing the device (Input terminal). This
  * is where addition of 1 comes from. In case of Headphones thill will always
  * be 3rd entity (Output terminal) - addition of 3.
  */
 #define HP_LINK(i) ((3*i) + 1)
 #define MIC_LINK(i) ((3*(HEADPHONES_DEVICE_COUNT + i)) + 3)

 /**
  * Addressable logical object inside an audio function.
  * Entity is one of: Terminal or Unit.
  * Refer to 1.4 Terms and Abbreviations from audio10.pdf
  */
 struct usb_audio_entity {
 	enum usb_audio_cs_ac_int_desc_subtypes subtype;
 	uint8_t id;
 };

 /**
  * @warning Size of baInterface is 2 just to make it usable
  * for all kind of devices: headphones, microphone and headset.
  * Actual size of the struct should be checked by reading
  * .bLength.
  */
 struct cs_ac_if_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint16_t bcdADC;
 	uint16_t wTotalLength;
 	uint8_t bInCollection;
 	uint8_t baInterfaceNr[2];
 } __packed;

 struct input_terminal_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint8_t bTerminalID;
 	uint16_t wTerminalType;
 	uint8_t bAssocTerminal;
 	uint8_t bNrChannels;
 	uint16_t wChannelConfig;
 	uint8_t iChannelNames;
 	uint8_t iTerminal;
 } __packed;

 /**
  * @note Size of Feature unit descriptor is not fixed.
  * This structure is just a helper not a common type.
  */
 struct feature_unit_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint8_t bUnitID;
 	uint8_t bSourceID;
 	uint8_t bControlSize;
 	uint16_t bmaControls[1];
 } __packed;

 struct output_terminal_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint8_t bTerminalID;
 	uint16_t wTerminalType;
 	uint8_t bAssocTerminal;
 	uint8_t bSourceID;
 	uint8_t iTerminal;
 } __packed;

 struct as_cs_interface_descriptor {
 	uint8_t  bLength;
 	uint8_t  bDescriptorType;
 	uint8_t  bDescriptorSubtype;
 	uint8_t  bTerminalLink;
 	uint8_t  bDelay;
 	uint16_t wFormatTag;
 } __packed;

 struct format_type_i_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint8_t bFormatType;
 	uint8_t bNrChannels;
 	uint8_t bSubframeSize;
 	uint8_t bBitResolution;
 	uint8_t bSamFreqType;
 	uint8_t tSamFreq[3];
 } __packed;

 struct std_as_ad_endpoint_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bEndpointAddress;
 	uint8_t bmAttributes;
 	uint16_t wMaxPacketSize;
 	uint8_t bInterval;
 	uint8_t bRefresh;
 	uint8_t bSynchAddress;
 } __packed;

 struct cs_as_ad_ep_descriptor {
 	uint8_t bLength;
 	uint8_t bDescriptorType;
 	uint8_t bDescriptorSubtype;
 	uint8_t bmAttributes;
 	uint8_t bLockDelayUnits;
 	uint16_t wLockDelay;
 } __packed;

 #define DECLARE_HEADER(dev, i, ifaces)	\
 struct dev##_cs_ac_if_descriptor_##i {	\
 	uint8_t bLength;			\
 	uint8_t bDescriptorType;		\
 	uint8_t bDescriptorSubtype;	\
 	uint16_t bcdADC;			\
 	uint16_t wTotalLength;		\
 	uint8_t bInCollection;		\
 	uint8_t baInterfaceNr[ifaces];	\
 } __packed

 #define DECLARE_FEATURE_UNIT(dev, i)		\
 struct dev##_feature_unit_descriptor_##i {	\
 	uint8_t bLength;				\
 	uint8_t bDescriptorType;			\
 	uint8_t bDescriptorSubtype;		\
 	uint8_t bUnitID;				\
 	uint8_t bSourceID;				\
 	uint8_t bControlSize;			\
 	uint16_t bmaControls[CH_CNT(dev, i) + 1];	\
 	uint8_t iFeature;				\
 } __packed

 #define INIT_IAD(iface_subclass, if_cnt)			\
 {								\
 	.bLength = sizeof(struct usb_association_descriptor),	\
 	.bDescriptorType = USB_DESC_INTERFACE_ASSOC,		\
 	.bFirstInterface = 0,					\
 	.bInterfaceCount = if_cnt,				\
 	.bFunctionClass = USB_BCC_AUDIO,			\
 	.bFunctionSubClass = iface_subclass,			\
 	.bFunctionProtocol = 0,					\
 	.iFunction = 0,						\
 }

 #ifdef CONFIG_USB_COMPOSITE_DEVICE
 #define USB_AUDIO_IAD_DECLARE struct usb_association_descriptor iad;
 #define USB_AUDIO_IAD(if_cnt)  .iad = INIT_IAD(USB_AUDIO_AUDIOCONTROL, if_cnt),
 #else
 #define USB_AUDIO_IAD_DECLARE
 #define USB_AUDIO_IAD(if_cnt)
 #endif

 #define DECLARE_DESCRIPTOR(dev, i, ifaces)				\
 DECLARE_HEADER(dev, i, ifaces);						\
 DECLARE_FEATURE_UNIT(dev, i);						\
 struct dev##_descriptor_##i {						\
 	USB_AUDIO_IAD_DECLARE						\
 	struct usb_if_descriptor std_ac_interface;			\
 	struct dev##_cs_ac_if_descriptor_##i cs_ac_interface;		\
 	struct input_terminal_descriptor input_terminal;		\
 	struct dev##_feature_unit_descriptor_##i feature_unit;		\
 	struct output_terminal_descriptor output_terminal;		\
 	struct usb_if_descriptor as_interface_alt_0;			\
 	struct usb_if_descriptor as_interface_alt_1;			\
 		struct as_cs_interface_descriptor as_cs_interface;	\
 		struct format_type_i_descriptor format;			\
 		struct std_as_ad_endpoint_descriptor std_ep;		\
 		struct cs_as_ad_ep_descriptor cs_ep;			\
 } __packed

 #define DECLARE_DESCRIPTOR_BIDIR(dev, i, ifaces)			\
 DECLARE_HEADER(dev, i, ifaces);						\
 DECLARE_FEATURE_UNIT(dev##_MIC, i);					\
 DECLARE_FEATURE_UNIT(dev##_HP, i);					\
 struct dev##_descriptor_##i {						\
 	USB_AUDIO_IAD_DECLARE						\
 	struct usb_if_descriptor std_ac_interface;			\
 	struct dev##_cs_ac_if_descriptor_##i cs_ac_interface;		\
 	struct input_terminal_descriptor input_terminal_0;		\
 	struct dev##_MIC_feature_unit_descriptor_##i feature_unit_0;	\
 	struct output_terminal_descriptor output_terminal_0;		\
 	struct input_terminal_descriptor input_terminal_1;		\
 	struct dev##_HP_feature_unit_descriptor_##i feature_unit_1;	\
 	struct output_terminal_descriptor output_terminal_1;		\
 	struct usb_if_descriptor as_interface_alt_0_0;			\
 	struct usb_if_descriptor as_interface_alt_0_1;			\
 		struct as_cs_interface_descriptor as_cs_interface_0;	\
 		struct format_type_i_descriptor format_0;		\
 		struct std_as_ad_endpoint_descriptor std_ep_0;		\
 		struct cs_as_ad_ep_descriptor cs_ep_0;			\
 	struct usb_if_descriptor as_interface_alt_1_0;			\
 	struct usb_if_descriptor as_interface_alt_1_1;			\
 		struct as_cs_interface_descriptor as_cs_interface_1;	\
 		struct format_type_i_descriptor format_1;		\
 		struct std_as_ad_endpoint_descriptor std_ep_1;		\
 		struct cs_as_ad_ep_descriptor cs_ep_1;			\
 } __packed

 #define INIT_STD_IF(iface_subclass, iface_num, alt_setting, eps_num)	\
 {									\
 	.bLength = sizeof(struct usb_if_descriptor),			\
 	.bDescriptorType = USB_DESC_INTERFACE,				\
 	.bInterfaceNumber = iface_num,					\
 	.bAlternateSetting = alt_setting,				\
 	.bNumEndpoints = eps_num,					\
 	.bInterfaceClass = USB_BCC_AUDIO,				\
 	.bInterfaceSubClass = iface_subclass,				\
 	.bInterfaceProtocol = 0,					\
 	.iInterface = 0,						\
 }

 #define INIT_CS_AC_IF(dev, i, ifaces)					\
 {									\
 	.bLength = sizeof(struct dev##_cs_ac_if_descriptor_##i),	\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,			\
 	.bDescriptorSubtype = USB_AUDIO_HEADER,				\
 	.bcdADC = sys_cpu_to_le16(0x0100),				\
 	.wTotalLength = sys_cpu_to_le16(				\
 		sizeof(struct dev##_cs_ac_if_descriptor_##i) +		\
 		INPUT_TERMINAL_DESC_SIZE +				\
 		sizeof(struct dev##_feature_unit_descriptor_##i) +	\
 		OUTPUT_TERMINAL_DESC_SIZE),				\
 	.bInCollection = ifaces,					\
 	.baInterfaceNr = {0},						\
 }

 #define INIT_CS_AC_IF_BIDIR(dev, i, ifaces)				\
 {									\
 	.bLength = sizeof(struct dev##_cs_ac_if_descriptor_##i),	\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,			\
 	.bDescriptorSubtype = USB_AUDIO_HEADER,				\
 	.bcdADC = sys_cpu_to_le16(0x0100),				\
 	.wTotalLength = sys_cpu_to_le16(				\
 		sizeof(struct dev##_cs_ac_if_descriptor_##i) +		\
 		2*INPUT_TERMINAL_DESC_SIZE +				\
 		sizeof(struct dev##_MIC_feature_unit_descriptor_##i) +	\
 		sizeof(struct dev##_HP_feature_unit_descriptor_##i) +	\
 		2*OUTPUT_TERMINAL_DESC_SIZE),				\
 	.bInCollection = ifaces,					\
 	.baInterfaceNr = {0},						\
 }

 #define INIT_IN_TERMINAL(dev, i, terminal_id, type)		\
 {								\
 	.bLength = INPUT_TERMINAL_DESC_SIZE,			\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,		\
 	.bDescriptorSubtype = USB_AUDIO_INPUT_TERMINAL,		\
 	.bTerminalID = terminal_id,				\
 	.wTerminalType = sys_cpu_to_le16(type),			\
 	.bAssocTerminal = 0,					\
 	.bNrChannels = MAX(1, CH_CNT(dev, i)),			\
 	.wChannelConfig = sys_cpu_to_le16(CH_CFG(dev, i)),	\
 	.iChannelNames = 0,					\
 	.iTerminal = 0,						\
 }

 #define INIT_OUT_TERMINAL(terminal_id, source_id, type)	\
 {							\
 	.bLength = OUTPUT_TERMINAL_DESC_SIZE,		\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,	\
 	.bDescriptorSubtype = USB_AUDIO_OUTPUT_TERMINAL,\
 	.bTerminalID = terminal_id,			\
 	.wTerminalType = sys_cpu_to_le16(type),		\
 	.bAssocTerminal = 0,				\
 	.bSourceID = source_id,				\
 	.iTerminal = 0,					\
 }

 /** refer to Table 4-7 from audio10.pdf
  */
 #define INIT_FEATURE_UNIT(dev, i, unit_id, source_id)			\
 {									\
 	.bLength = sizeof(struct dev##_feature_unit_descriptor_##i),	\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,			\
 	.bDescriptorSubtype = USB_AUDIO_FEATURE_UNIT,			\
 	.bUnitID = unit_id,						\
 	.bSourceID = source_id,						\
 	.bControlSize = sizeof(uint16_t),					\
 	.bmaControls = { FEATURES(dev, i) },				\
 	.iFeature = 0,							\
 }

 /* Class-Specific AS Interface Descriptor 4.5.2 audio10.pdf */
 #define INIT_AS_GENERAL(link)				\
 {							\
 	.bLength = USB_AC_CS_IF_DESC_SIZE,		\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,	\
 	.bDescriptorSubtype = USB_AUDIO_AS_GENERAL,	\
 	.bTerminalLink = link,				\
 	.bDelay = 0,					\
 	.wFormatTag = sys_cpu_to_le16(0x0001),		\
 }

 /** Class-Specific AS Format Type Descriptor 4.5.3 audio10.pdf
  *  For more information refer to 2.2.5 Type I Format Type Descriptor
  *  from frmts10.pdf
  */
 #define INIT_AS_FORMAT_I(ch_cnt, res)				\
 {								\
 	.bLength = sizeof(struct format_type_i_descriptor),	\
 	.bDescriptorType = USB_DESC_CS_INTERFACE,		\
 	.bDescriptorSubtype = USB_AUDIO_FORMAT_TYPE,		\
 	.bFormatType = 0x01,					\
 	.bNrChannels = MAX(1, ch_cnt),				\
 	.bSubframeSize = res/8,					\
 	.bBitResolution = res,					\
 	.bSamFreqType = 1,					\
 	.tSamFreq = {0x80, 0xBB, 0x00},				\
 }

 #define INIT_STD_AS_AD_EP(dev, i, addr)					\
 {									\
 	.bLength = sizeof(struct std_as_ad_endpoint_descriptor),	\
 	.bDescriptorType = USB_DESC_ENDPOINT,				\
 	.bEndpointAddress = addr,					\
 	.bmAttributes = (USB_DC_EP_ISOCHRONOUS | SYNC_TYPE(dev, i)),	\
 	.wMaxPacketSize = sys_cpu_to_le16(EP_SIZE(dev, i)),		\
 	.bInterval = 0x01,						\
 	.bRefresh = 0x00,						\
 	.bSynchAddress = 0x00,						\
 }

 #define INIT_CS_AS_AD_EP					\
 {								\
 	.bLength = sizeof(struct cs_as_ad_ep_descriptor),	\
 	.bDescriptorType = USB_DESC_CS_ENDPOINT,		\
 	.bDescriptorSubtype = 0x01,				\
 	.bmAttributes = 0x00,					\
 	.bLockDelayUnits = 0x00,				\
 	.wLockDelay = 0,					\
 }

 #define INIT_EP_DATA(cb, addr)	\
 	{			\
 		.ep_cb = cb,	\
 		.ep_addr = addr,\
 	}

 #endif /* ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_ */
	/*
	* USB audio class internal header
	*
	* Copyright (c) 2020 Nordic Semiconductor ASA
	*
	* SPDX-License-Identifier: Apache-2.0
	*/

	/**
	* @file
	* @brief USB Audio Device Class internal header
	*
	* This header file is used to store internal configuration
	* defines.
	*/

	#ifndef ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_
	#define ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_

	#define DUMMY_API (const void *)1

	#define USB_PASSIVE_IF_DESC_SIZE sizeof(struct usb_if_descriptor)
	#define USB_AC_CS_IF_DESC_SIZE sizeof(struct as_cs_interface_descriptor)
	#define USB_FORMAT_TYPE_I_DESC_SIZE sizeof(struct format_type_i_descriptor)
	#define USB_STD_AS_AD_EP_DESC_SIZE sizeof(struct std_as_ad_endpoint_descriptor)
	#define USB_CS_AS_AD_EP_DESC_SIZE sizeof(struct cs_as_ad_ep_descriptor)
	#define USB_ACTIVE_IF_DESC_SIZE (USB_PASSIVE_IF_DESC_SIZE + \
	USB_AC_CS_IF_DESC_SIZE + \
	USB_FORMAT_TYPE_I_DESC_SIZE + \
	USB_STD_AS_AD_EP_DESC_SIZE + \
	USB_CS_AS_AD_EP_DESC_SIZE)

	#define INPUT_TERMINAL_DESC_SIZE sizeof(struct input_terminal_descriptor)
	#define OUTPUT_TERMINAL_DESC_SIZE sizeof(struct output_terminal_descriptor)

	#define BMA_CONTROLS_OFFSET 6
	#define FU_FIXED_ELEMS_SIZE 7

	/* Macros for maintaining features of feature unit entity */
	#define FEATURE_MUTE_SIZE 0x01
	#define FEATURE_VOLUME_SIZE 0x02
	#define FEATURE_BASS_SIZE 0x01
	#define FEATURE_MID_SIZE 0x01
	#define FEATURE_TREBLE_SIZE 0x01
	#define FEATURE_TONE_CONTROL_SIZE (FEATURE_BASS_SIZE +\
	FEATURE_MID_SIZE + \
	FEATURE_TREBLE_SIZE)
	#define FEATURE_GRAPHIC_EQUALIZER_SIZE 0x01
	#define FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE 0x01
	#define FEATURE_DELAY_SIZE 0x02
	#define FEATURE_BASS_BOOST_SIZE 0x01
	#define FEATURE_LOUDNESS_SIZE 0x01

	#define POS_MUTE 0
	#define POS_VOLUME (POS_MUTE + FEATURE_MUTE_SIZE)
	#define POS_BASS (POS_VOLUME + FEATURE_VOLUME_SIZE)
	#define POS_MID (POS_BASS + FEATURE_BASS_SIZE)
	#define POS_TREBLE (POS_MID + FEATURE_MID_SIZE)
	#define POS_GRAPHIC_EQUALIZER (POS_TREBLE + FEATURE_TREBLE_SIZE)
	#define POS_AUTOMATIC_GAIN_CONTROL (POS_GRAPHIC_EQUALIZER + \
	FEATURE_GRAPHIC_EQUALIZER_SIZE)
	#define POS_DELAY (POS_AUTOMATIC_GAIN_CONTROL + \
	FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE)
	#define POS_BASS_BOOST (POS_DELAY + FEATURE_DELAY_SIZE)
	#define POS_LOUDNESS (POS_BASS_BOOST + FEATURE_BASS_BOOST_SIZE)

	#define POS(prop, ch_idx, ch_cnt) (ch_cnt * POS_##prop + \
	(ch_idx * FEATURE_##prop##_SIZE))
	#define LEN(ch_cnt, prop) (ch_cnt * FEATURE_##prop##_SIZE)

	/* Names of compatibles used for configuration of the device */
	#define COMPAT_HP usb_audio_hp
	#define COMPAT_MIC usb_audio_mic
	#define COMPAT_HS usb_audio_hs

	#define HEADPHONES_DEVICE_COUNT DT_NUM_INST_STATUS_OKAY(COMPAT_HP)
	#define MICROPHONE_DEVICE_COUNT DT_NUM_INST_STATUS_OKAY(COMPAT_MIC)
	#define HEADSET_DEVICE_COUNT DT_NUM_INST_STATUS_OKAY(COMPAT_HS)

	#define IF_USB_AUDIO_PROP_HP(i, prop, bitmask) \
	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HP), prop), (bitmask), (0))
	#define IF_USB_AUDIO_PROP_MIC(i, prop, bitmask) \
	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_MIC), prop), (bitmask), (0))
	#define IF_USB_AUDIO_PROP_HS_HP(i, prop, bitmask) \
	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HS), hp_##prop), (bitmask), (0))
	#define IF_USB_AUDIO_PROP_HS_MIC(i, prop, bitmask) \
	COND_CODE_1(DT_PROP(DT_INST(i, COMPAT_HS), mic_##prop), (bitmask), (0))
	#define IF_USB_AUDIO_PROP(dev, i, prop, bitmask) \
	IF_USB_AUDIO_PROP_##dev(i, prop, bitmask)

	/* Macro for getting the bitmask of configured channels for given device */
	#define CH_CFG(dev, i) (0x0000 \
	\| IF_USB_AUDIO_PROP(dev, i, channel_l, BIT(0)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_r, BIT(1)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_c, BIT(2)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_lfe, BIT(3)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_ls, BIT(4)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_rs, BIT(5)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_lc, BIT(6)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_rc, BIT(7)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_s, BIT(8)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_sl, BIT(9)) \
	\| IF_USB_AUDIO_PROP(dev, i, channel_sr, BIT(10))\
	\| IF_USB_AUDIO_PROP(dev, i, channel_t, BIT(11))\
	)

	/* Macro for getting the number of configured channels for given device.
	* Master channel (0) excluded.
	*/
	#define CH_CNT(dev, i) (0 \
	+ IF_USB_AUDIO_PROP(dev, i, channel_l, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_r, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_c, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_lfe, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_ls, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_rs, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_lc, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_rc, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_s, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_sl, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_sr, 1)\
	+ IF_USB_AUDIO_PROP(dev, i, channel_t, 1)\
	)

	/* Macro for getting bitmask of supported features for given device */
	#define FEATURES(dev, i) (0x0000 \
	\| IF_USB_AUDIO_PROP(dev, i, feature_mute, BIT(0)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_volume, BIT(1)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_tone_control, BIT(2) \| BIT(3) \| BIT(4))\
	\| IF_USB_AUDIO_PROP(dev, i, feature_graphic_equalizer, BIT(5)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_automatic_gain_control, BIT(6)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_delay, BIT(7)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_bass_boost, BIT(8)) \
	\| IF_USB_AUDIO_PROP(dev, i, feature_loudness, BIT(9)) \
	)

	/* Macro for getting required size to store values for supported features. */
	#define FEATURES_SIZE(dev, i) ((CH_CNT(dev, i) + 1) * (0x0000 \
	+ IF_USB_AUDIO_PROP(dev, i, feature_mute, \
	FEATURE_MUTE_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_volume, \
	FEATURE_VOLUME_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_tone_control, \
	FEATURE_TONE_CONTROL_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_graphic_equalizer, \
	FEATURE_GRAPHIC_EQUALIZER_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_automatic_gain_control, \
	FEATURE_AUTOMATIC_GAIN_CONTROL_SIZE)\
	+ IF_USB_AUDIO_PROP(dev, i, feature_delay, \
	FEATURE_DELAY_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_bass_boost, \
	FEATURE_BASS_BOOST_SIZE) \
	+ IF_USB_AUDIO_PROP(dev, i, feature_loudness, \
	FEATURE_LOUDNESS_SIZE) \
	))

	#define GET_RES_HP(i) DT_PROP(DT_INST(i, COMPAT_HP), resolution)
	#define GET_RES_MIC(i) DT_PROP(DT_INST(i, COMPAT_MIC), resolution)
	#define GET_RES_HS_HP(i) DT_PROP(DT_INST(i, COMPAT_HS), hp_resolution)
	#define GET_RES_HS_MIC(i) DT_PROP(DT_INST(i, COMPAT_HS), mic_resolution)
	#define GET_RES(dev, i) GET_RES_##dev(i)

	#define SYNC_TYPE_HP(i) 3
	#define SYNC_TYPE_MIC(i) DT_ENUM_IDX(DT_INST(i, COMPAT_MIC), sync_type)
	#define SYNC_TYPE_HS_HP(i) 3
	#define SYNC_TYPE_HS_MIC(i) DT_ENUM_IDX(DT_INST(i, COMPAT_HS), mic_sync_type)
	#define SYNC_TYPE(dev, i) (SYNC_TYPE_##dev(i) << 2)

	#define EP_SIZE(dev, i) \
	((GET_RES(dev, i)/8) * CH_CNT(dev, i) * 48)

	/* *_ID() macros are used to give proper Id to each entity describing
	* the device. Entities Id must start from 1 that's why 1 is added.
	* Multiplication by 3 for HP/MIC comes from the fact that 3 entities are
	* required to describe the device, 6 in case of HS.
	*/
	#define HP_ID(i) ((3*i) + 1)
	#define MIC_ID(i) ((3*(HEADPHONES_DEVICE_COUNT + i)) + 1)
	#define HS_ID(i) ((3*(HEADPHONES_DEVICE_COUNT + \
	MICROPHONE_DEVICE_COUNT)) + 6*i + 1)

	/* *_LINK() macros are used to properly connect relevant audio streaming
	* class specific interface with valid entity. In case of Headphones this
	* will always be 1st entity describing the device (Input terminal). This
	* is where addition of 1 comes from. In case of Headphones thill will always
	* be 3rd entity (Output terminal) - addition of 3.
	*/
	#define HP_LINK(i) ((3*i) + 1)
	#define MIC_LINK(i) ((3*(HEADPHONES_DEVICE_COUNT + i)) + 3)

	/**
	* Addressable logical object inside an audio function.
	* Entity is one of: Terminal or Unit.
	* Refer to 1.4 Terms and Abbreviations from audio10.pdf
	*/
	struct usb_audio_entity {
	enum usb_audio_cs_ac_int_desc_subtypes subtype;
	uint8_t id;
	};

	/**
	* @warning Size of baInterface is 2 just to make it usable
	* for all kind of devices: headphones, microphone and headset.
	* Actual size of the struct should be checked by reading
	* .bLength.
	*/
	struct cs_ac_if_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint16_t bcdADC;
	uint16_t wTotalLength;
	uint8_t bInCollection;
	uint8_t baInterfaceNr[2];
	} __packed;

	struct input_terminal_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bTerminalID;
	uint16_t wTerminalType;
	uint8_t bAssocTerminal;
	uint8_t bNrChannels;
	uint16_t wChannelConfig;
	uint8_t iChannelNames;
	uint8_t iTerminal;
	} __packed;

	/**
	* @note Size of Feature unit descriptor is not fixed.
	* This structure is just a helper not a common type.
	*/
	struct feature_unit_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bUnitID;
	uint8_t bSourceID;
	uint8_t bControlSize;
	uint16_t bmaControls[1];
	} __packed;

	struct output_terminal_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bTerminalID;
	uint16_t wTerminalType;
	uint8_t bAssocTerminal;
	uint8_t bSourceID;
	uint8_t iTerminal;
	} __packed;

	struct as_cs_interface_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bTerminalLink;
	uint8_t bDelay;
	uint16_t wFormatTag;
	} __packed;

	struct format_type_i_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bFormatType;
	uint8_t bNrChannels;
	uint8_t bSubframeSize;
	uint8_t bBitResolution;
	uint8_t bSamFreqType;
	uint8_t tSamFreq[3];
	} __packed;

	struct std_as_ad_endpoint_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bEndpointAddress;
	uint8_t bmAttributes;
	uint16_t wMaxPacketSize;
	uint8_t bInterval;
	uint8_t bRefresh;
	uint8_t bSynchAddress;
	} __packed;

	struct cs_as_ad_ep_descriptor {
	uint8_t bLength;
	uint8_t bDescriptorType;
	uint8_t bDescriptorSubtype;
	uint8_t bmAttributes;
	uint8_t bLockDelayUnits;
	uint16_t wLockDelay;
	} __packed;

	#define DECLARE_HEADER(dev, i, ifaces) \
	struct dev##_cs_ac_if_descriptor_##i { \
	uint8_t bLength; \
	uint8_t bDescriptorType; \
	uint8_t bDescriptorSubtype; \
	uint16_t bcdADC; \
	uint16_t wTotalLength; \
	uint8_t bInCollection; \
	uint8_t baInterfaceNr[ifaces]; \
	} __packed

	#define DECLARE_FEATURE_UNIT(dev, i) \
	struct dev##_feature_unit_descriptor_##i { \
	uint8_t bLength; \
	uint8_t bDescriptorType; \
	uint8_t bDescriptorSubtype; \
	uint8_t bUnitID; \
	uint8_t bSourceID; \
	uint8_t bControlSize; \
	uint16_t bmaControls[CH_CNT(dev, i) + 1]; \
	uint8_t iFeature; \
	} __packed

	#define INIT_IAD(iface_subclass, if_cnt) \
	{ \
	.bLength = sizeof(struct usb_association_descriptor), \
	.bDescriptorType = USB_DESC_INTERFACE_ASSOC, \
	.bFirstInterface = 0, \
	.bInterfaceCount = if_cnt, \
	.bFunctionClass = USB_BCC_AUDIO, \
	.bFunctionSubClass = iface_subclass, \
	.bFunctionProtocol = 0, \
	.iFunction = 0, \
	}

	#ifdef CONFIG_USB_COMPOSITE_DEVICE
	#define USB_AUDIO_IAD_DECLARE struct usb_association_descriptor iad;
	#define USB_AUDIO_IAD(if_cnt) .iad = INIT_IAD(USB_AUDIO_AUDIOCONTROL, if_cnt),
	#else
	#define USB_AUDIO_IAD_DECLARE
	#define USB_AUDIO_IAD(if_cnt)
	#endif

	#define DECLARE_DESCRIPTOR(dev, i, ifaces) \
	DECLARE_HEADER(dev, i, ifaces); \
	DECLARE_FEATURE_UNIT(dev, i); \
	struct dev##_descriptor_##i { \
	USB_AUDIO_IAD_DECLARE \
	struct usb_if_descriptor std_ac_interface; \
	struct dev##_cs_ac_if_descriptor_##i cs_ac_interface; \
	struct input_terminal_descriptor input_terminal; \
	struct dev##_feature_unit_descriptor_##i feature_unit; \
	struct output_terminal_descriptor output_terminal; \
	struct usb_if_descriptor as_interface_alt_0; \
	struct usb_if_descriptor as_interface_alt_1; \
	struct as_cs_interface_descriptor as_cs_interface; \
	struct format_type_i_descriptor format; \
	struct std_as_ad_endpoint_descriptor std_ep; \
	struct cs_as_ad_ep_descriptor cs_ep; \
	} __packed

	#define DECLARE_DESCRIPTOR_BIDIR(dev, i, ifaces) \
	DECLARE_HEADER(dev, i, ifaces); \
	DECLARE_FEATURE_UNIT(dev##_MIC, i); \
	DECLARE_FEATURE_UNIT(dev##_HP, i); \
	struct dev##_descriptor_##i { \
	USB_AUDIO_IAD_DECLARE \
	struct usb_if_descriptor std_ac_interface; \
	struct dev##_cs_ac_if_descriptor_##i cs_ac_interface; \
	struct input_terminal_descriptor input_terminal_0; \
	struct dev##_MIC_feature_unit_descriptor_##i feature_unit_0; \
	struct output_terminal_descriptor output_terminal_0; \
	struct input_terminal_descriptor input_terminal_1; \
	struct dev##_HP_feature_unit_descriptor_##i feature_unit_1; \
	struct output_terminal_descriptor output_terminal_1; \
	struct usb_if_descriptor as_interface_alt_0_0; \
	struct usb_if_descriptor as_interface_alt_0_1; \
	struct as_cs_interface_descriptor as_cs_interface_0; \
	struct format_type_i_descriptor format_0; \
	struct std_as_ad_endpoint_descriptor std_ep_0; \
	struct cs_as_ad_ep_descriptor cs_ep_0; \
	struct usb_if_descriptor as_interface_alt_1_0; \
	struct usb_if_descriptor as_interface_alt_1_1; \
	struct as_cs_interface_descriptor as_cs_interface_1; \
	struct format_type_i_descriptor format_1; \
	struct std_as_ad_endpoint_descriptor std_ep_1; \
	struct cs_as_ad_ep_descriptor cs_ep_1; \
	} __packed

	#define INIT_STD_IF(iface_subclass, iface_num, alt_setting, eps_num) \
	{ \
	.bLength = sizeof(struct usb_if_descriptor), \
	.bDescriptorType = USB_DESC_INTERFACE, \
	.bInterfaceNumber = iface_num, \
	.bAlternateSetting = alt_setting, \
	.bNumEndpoints = eps_num, \
	.bInterfaceClass = USB_BCC_AUDIO, \
	.bInterfaceSubClass = iface_subclass, \
	.bInterfaceProtocol = 0, \
	.iInterface = 0, \
	}

	#define INIT_CS_AC_IF(dev, i, ifaces) \
	{ \
	.bLength = sizeof(struct dev##_cs_ac_if_descriptor_##i), \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_HEADER, \
	.bcdADC = sys_cpu_to_le16(0x0100), \
	.wTotalLength = sys_cpu_to_le16( \
	sizeof(struct dev##_cs_ac_if_descriptor_##i) + \
	INPUT_TERMINAL_DESC_SIZE + \
	sizeof(struct dev##_feature_unit_descriptor_##i) + \
	OUTPUT_TERMINAL_DESC_SIZE), \
	.bInCollection = ifaces, \
	.baInterfaceNr = {0}, \
	}

	#define INIT_CS_AC_IF_BIDIR(dev, i, ifaces) \
	{ \
	.bLength = sizeof(struct dev##_cs_ac_if_descriptor_##i), \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_HEADER, \
	.bcdADC = sys_cpu_to_le16(0x0100), \
	.wTotalLength = sys_cpu_to_le16( \
	sizeof(struct dev##_cs_ac_if_descriptor_##i) + \
	2*INPUT_TERMINAL_DESC_SIZE + \
	sizeof(struct dev##_MIC_feature_unit_descriptor_##i) + \
	sizeof(struct dev##_HP_feature_unit_descriptor_##i) + \
	2*OUTPUT_TERMINAL_DESC_SIZE), \
	.bInCollection = ifaces, \
	.baInterfaceNr = {0}, \
	}

	#define INIT_IN_TERMINAL(dev, i, terminal_id, type) \
	{ \
	.bLength = INPUT_TERMINAL_DESC_SIZE, \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_INPUT_TERMINAL, \
	.bTerminalID = terminal_id, \
	.wTerminalType = sys_cpu_to_le16(type), \
	.bAssocTerminal = 0, \
	.bNrChannels = MAX(1, CH_CNT(dev, i)), \
	.wChannelConfig = sys_cpu_to_le16(CH_CFG(dev, i)), \
	.iChannelNames = 0, \
	.iTerminal = 0, \
	}

	#define INIT_OUT_TERMINAL(terminal_id, source_id, type) \
	{ \
	.bLength = OUTPUT_TERMINAL_DESC_SIZE, \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_OUTPUT_TERMINAL,\
	.bTerminalID = terminal_id, \
	.wTerminalType = sys_cpu_to_le16(type), \
	.bAssocTerminal = 0, \
	.bSourceID = source_id, \
	.iTerminal = 0, \
	}

	/** refer to Table 4-7 from audio10.pdf
	*/
	#define INIT_FEATURE_UNIT(dev, i, unit_id, source_id) \
	{ \
	.bLength = sizeof(struct dev##_feature_unit_descriptor_##i), \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_FEATURE_UNIT, \
	.bUnitID = unit_id, \
	.bSourceID = source_id, \
	.bControlSize = sizeof(uint16_t), \
	.bmaControls = { FEATURES(dev, i) }, \
	.iFeature = 0, \
	}

	/* Class-Specific AS Interface Descriptor 4.5.2 audio10.pdf */
	#define INIT_AS_GENERAL(link) \
	{ \
	.bLength = USB_AC_CS_IF_DESC_SIZE, \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_AS_GENERAL, \
	.bTerminalLink = link, \
	.bDelay = 0, \
	.wFormatTag = sys_cpu_to_le16(0x0001), \
	}

	/** Class-Specific AS Format Type Descriptor 4.5.3 audio10.pdf
	* For more information refer to 2.2.5 Type I Format Type Descriptor
	* from frmts10.pdf
	*/
	#define INIT_AS_FORMAT_I(ch_cnt, res) \
	{ \
	.bLength = sizeof(struct format_type_i_descriptor), \
	.bDescriptorType = USB_DESC_CS_INTERFACE, \
	.bDescriptorSubtype = USB_AUDIO_FORMAT_TYPE, \
	.bFormatType = 0x01, \
	.bNrChannels = MAX(1, ch_cnt), \
	.bSubframeSize = res/8, \
	.bBitResolution = res, \
	.bSamFreqType = 1, \
	.tSamFreq = {0x80, 0xBB, 0x00}, \
	}

	#define INIT_STD_AS_AD_EP(dev, i, addr) \
	{ \
	.bLength = sizeof(struct std_as_ad_endpoint_descriptor), \
	.bDescriptorType = USB_DESC_ENDPOINT, \
	.bEndpointAddress = addr, \
	.bmAttributes = (USB_DC_EP_ISOCHRONOUS \| SYNC_TYPE(dev, i)), \
	.wMaxPacketSize = sys_cpu_to_le16(EP_SIZE(dev, i)), \
	.bInterval = 0x01, \
	.bRefresh = 0x00, \
	.bSynchAddress = 0x00, \
	}

	#define INIT_CS_AS_AD_EP \
	{ \
	.bLength = sizeof(struct cs_as_ad_ep_descriptor), \
	.bDescriptorType = USB_DESC_CS_ENDPOINT, \
	.bDescriptorSubtype = 0x01, \
	.bmAttributes = 0x00, \
	.bLockDelayUnits = 0x00, \
	.wLockDelay = 0, \
	}

	#define INIT_EP_DATA(cb, addr) \
	{ \
	.ep_cb = cb, \
	.ep_addr = addr,\
	}

	#endif /* ZEPHYR_INCLUDE_USB_CLASS_AUDIO_INTERNAL_H_ */