STM32 USB音频麦克风实现
Posted aron566
tags:
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最近项目进入收尾阶段，USB Microphone 部分代码不是我所实现，接口较为松散，所以决定优化这部分代码，啃一啃USB部分知识点，一两天肯定不能完全了解清晰，毕竟万能USB，其协议必然是复杂的，所以就先从音频麦克风的实现开始。
其实是币圈大跌，努力搬砖中…
调试工具
usbtreeview（一款方便查看USB设备相关信息的免安装绿色工具）
Audacity (音频频谱查看工具，可查看麦克风设备列表，进行音频录制)
资料书籍
<<圈圈教你玩USB 第二版>>
音频描述符中的简称及分类
- AC：Audio Control
- AS：Audio Stream
拓扑图如下：
控制接口下，默认为端点0
接口描述符
查看位置：usbd_xxx.h，xxx代表某个功能如：audio
在这个文件中可以找到这个USB功能类的相关描述符定义
-
Terminal 以设备为视角看待
- Terminal 的输入输出成对出现
-
endpoint 以HOST为视角看待
下图为一个speeaker即扬声器 USB拓扑
endpoint 以HOST为视角看待，即主机的输出口 endpoint1 的音频数据流，转入了设备端的输入口Terminal IN
那么麦克风的配置
usbd_audio.c
iConfiguration iTerminal iInterfaceiChannelNames其数值，都是在说明本描述符的字符串说明符，所在索引号，若为0则没有字符串说明（没有文字说明）
-
wTerminalType
- 音频流：0x0101
- 麦克风：0x0201
- 电话线：0x0501
- 手持电话筒的输入麦克风：0x0401
如果麦克风数据需要通过USB上传至PC那么：
麦克风数据 --》(USB设备)MCU -》（USB主机）PC
麦克风数据 --》 terminal IN -》terminal OUT -》 Endpoint IN
STM32配置
打开USB设备功能 FS( Full Speed 全速设备)
配置USB Audio库，配置音频的采样率
一般CubeMX会自动打开USB的全局中断，生成代码后，自己最好确认一下（位于usbd_config.c）。
以下usbd_audio.c和对应头文件可直接替换，自动生成的。
修改usbd_audio.c文件
/**
******************************************************************************
* @file usbd_audio.c
* @author MCD Application Team
* @brief This file provides the Audio core functions.
*
* @verbatim
*
* ===================================================================
* AUDIO Class Description
* ===================================================================
* This driver manages the Audio Class 1.0 following the "USB Device Class Definition for
* Audio Devices V1.0 Mar 18, 98".
* This driver implements the following aspects of the specification:
* - Device descriptor management
* - Configuration descriptor management
* - Standard AC Interface Descriptor management
* - 1 Audio Streaming Interface (with single channel, PCM, Stereo mode)
* - 1 Audio Streaming Endpoint
* - 1 Audio Terminal Input (1 channel)
* - Audio Class-Specific AC Interfaces
* - Audio Class-Specific AS Interfaces
* - AudioControl Requests: only SET_CUR and GET_CUR requests are supported (for Mute)
* - Audio Feature Unit (limited to Mute control)
* - Audio Synchronization type: Asynchronous
* - Single fixed audio sampling rate (configurable in usbd_conf.h file)
* The current audio class version supports the following audio features:
* - Pulse Coded Modulation (PCM) format
* - sampling rate: 48KHz.
* - Bit resolution: 16
* - Number of channels: 2
* - No volume control
* - Mute/Unmute capability
* - Asynchronous Endpoints
*
* @note In HS mode and when the DMA is used, all variables and data structures
* dealing with the DMA during the transaction process should be 32-bit aligned.
*
*
* @endverbatim
*
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2015 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under Ultimate Liberty license
* SLA0044, the "License"; You may not use this file except in compliance with
* the License. You may obtain a copy of the License at:
* www.st.com/SLA0044
*
******************************************************************************
*/
/* BSPDependencies
- "stm32xxxxx_{eval}{discovery}.c"
- "stm32xxxxx_{eval}{discovery}_io.c"
- "stm32xxxxx_{eval}{discovery}_audio.c"
EndBSPDependencies */
/* Includes ------------------------------------------------------------------*/
#include "usbd_audio.h"
#include "usbd_ctlreq.h"
/** @addtogroup STM32_USB_DEVICE_LIBRARY
* @{
*/
/** @defgroup USBD_AUDIO
* @brief usbd core module
* @{
*/
/** @defgroup USBD_AUDIO_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @defgroup USBD_AUDIO_Private_Defines
* @{
*/
/**
* @}
*/
/** @defgroup USBD_AUDIO_Private_Macros
* @{
*/
#define AUDIO_SAMPLE_FREQ(frq) (uint8_t)(frq), (uint8_t)((frq >> 8)), (uint8_t)((frq >> 16))
#define AUDIO_PACKET_SZE(frq) (uint8_t)(((frq * 2U * 2U)/1000U) & 0xFFU), \\
(uint8_t)((((frq * 2U * 2U)/1000U) >> 8) & 0xFFU)
/**
* @}
*/
/** @defgroup USBD_AUDIO_Private_FunctionPrototypes
* @{
*/
static uint8_t USBD_AUDIO_Init(USBD_HandleTypeDef *pdev, uint8_t cfgidx);
static uint8_t USBD_AUDIO_DeInit(USBD_HandleTypeDef *pdev, uint8_t cfgidx);
static uint8_t USBD_AUDIO_Setup(USBD_HandleTypeDef *pdev,
USBD_SetupReqTypedef *req);
static uint8_t *USBD_AUDIO_GetCfgDesc(uint16_t *length);
static uint8_t *USBD_AUDIO_GetDeviceQualifierDesc(uint16_t *length);
static uint8_t USBD_AUDIO_DataIn(USBD_HandleTypeDef *pdev, uint8_t epnum);
static uint8_t USBD_AUDIO_DataOut(USBD_HandleTypeDef *pdev, uint8_t epnum);
static uint8_t USBD_AUDIO_EP0_RxReady(USBD_HandleTypeDef *pdev);
static uint8_t USBD_AUDIO_EP0_TxReady(USBD_HandleTypeDef *pdev);
static uint8_t USBD_AUDIO_SOF(USBD_HandleTypeDef *pdev);
static uint8_t USBD_AUDIO_IsoINIncomplete(USBD_HandleTypeDef *pdev, uint8_t epnum);
static uint8_t USBD_AUDIO_IsoOutIncomplete(USBD_HandleTypeDef *pdev, uint8_t epnum);
static void AUDIO_REQ_GetCurrent(USBD_HandleTypeDef *pdev, USBD_SetupReqTypedef *req);
static void AUDIO_REQ_SetCurrent(USBD_HandleTypeDef *pdev, USBD_SetupReqTypedef *req);
/**
* @}
*/
/** @defgroup USBD_AUDIO_Private_Variables
* @{
*/
USBD_ClassTypeDef USBD_AUDIO =
{
USBD_AUDIO_Init,
USBD_AUDIO_DeInit,
USBD_AUDIO_Setup,
USBD_AUDIO_EP0_TxReady,
USBD_AUDIO_EP0_RxReady,
USBD_AUDIO_DataIn,
USBD_AUDIO_DataOut,
USBD_AUDIO_SOF,
USBD_AUDIO_IsoINIncomplete,
USBD_AUDIO_IsoOutIncomplete,
USBD_AUDIO_GetCfgDesc,
USBD_AUDIO_GetCfgDesc,
USBD_AUDIO_GetCfgDesc,
USBD_AUDIO_GetDeviceQualifierDesc,
};
/* USB AUDIO device Configuration Descriptor */
__ALIGN_BEGIN static uint8_t USBD_AUDIO_CfgDesc[USB_AUDIO_CONFIG_DESC_SIZ] __ALIGN_END =
{
/* Configuration 1 */
0x09, /* bLength */
USB_DESC_TYPE_CONFIGURATION, /* bDescriptorType */
LOBYTE(USB_AUDIO_CONFIG_DESC_SIZ), /* wTotalLength 109 bytes*/
HIBYTE(USB_AUDIO_CONFIG_DESC_SIZ),
0x02, /* bNumInterfaces */
0x01, /* bConfigurationValue */
0x00, /* iConfiguration */
#if (USBD_SELF_POWERED == 1U)
0xC0, /* bmAttributes: Bus Powered according to user configuration */
#else
0x80, /* bmAttributes: Bus Powered according to user configuration */
#endif
USBD_MAX_POWER, /* bMaxPower = 100 mA */
/* 09 byte*/
/* USB Microphone Standard interface descriptor */
AUDIO_INTERFACE_DESC_SIZE, /* bLength */
USB_DESC_TYPE_INTERFACE, /* bDescriptorType */
0x00, /* bInterfaceNumber */
0x00, /* bAlternateSetting */
0x00, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDIOCONTROL, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* USB Microphone Class-specific AC Interface Descriptor */
AUDIO_INTERFACE_DESC_SIZE, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_HEADER, /* bDescriptorSubtype */
0x00, /* 1.00 */ /* bcdADC */
0x01,
0x27, /* wTotalLength = 39*/
0x00,
0x01, /* bInCollection */
0x01, /* baInterfaceNr */
/* 09 byte*/
/* USB Microphone Input Terminal Descriptor */
AUDIO_INPUT_TERMINAL_DESC_SIZE, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_INPUT_TERMINAL, /* bDescriptorSubtype */
AUDIO_PORT_INPUT_TERMINAL_ID_1, /* bTerminalID */
AUDIO_PORT_MICRO_PHONE_TERMINAL_L, /* wTerminalType AUDIO_TERMINAL_USB_Microphone 0x0201 */
AUDIO_PORT_MICRO_PHONE_TERMINAL_H,
0x00, /* bAssocTerminal */
AUDIO_PORT_CHANNEL_NUMS, /* bNrChannels */
AUDIO_PORT_CHANNEL_CONFIG_L, /* wChannelConfig 0x0000 Mono or L+R or L or R*/
AUDIO_PORT_CHANNEL_CONFIG_H,
0x00, /* iChannelNames */
0x00, /* iTerminal */
/* 12 byte*/
/* USB Microphone Audio Feature Unit Descriptor */
0x09, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_FEATURE_UNIT, /* bDescriptorSubtype */
AUDIO_PORT_INPUT_CTL_ID_2, /* bUnitID */
AUDIO_PORT_INPUT_TERMINAL_ID_1, /* bSourceID */
0x01, /* bControlSize */
AUDIO_CONTROL_MUTE, /* bmaControls(0) */
0, /* bmaControls(1) */
0x00, /* iTerminal */
/* 09 byte*/
/*USB Microphone Output Terminal Descriptor */
0x09, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_CONTROL_OUTPUT_TERMINAL, /* bDescriptorSubtype */
AUDIO_PORT_OUTPUT_TERMINAL_ID_3, /* bTerminalID */
AUDIO_PORT_STREAM_TERMINAL_TYPE_L, /* wTerminalType 音频流0x0101*/
AUDIO_PORT_STREAM_TERMINAL_TYPE_H,
0x00, /* bAssocTerminal */
AUDIO_PORT_INPUT_CTL_ID_2, /* bSourceID */
0x00, /* iTerminal */
/* 09 byte*/
/* USB Microphone Standard AS Interface Descriptor - Audio Streaming Zero Bandwidth */
/* Interface 1, Alternate Setting 0 */
AUDIO_INTERFACE_DESC_SIZE, /* bLength */
USB_DESC_TYPE_INTERFACE, /* bDescriptorType */
0x01, /* bInterfaceNumber */
0x00, /* bAlternateSetting */
0x00, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDiosTREAMING, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* USB Microphone Standard AS Interface Descriptor - Audio Streaming Operational */
/* Interface 1, Alternate Setting 1 */
AUDIO_INTERFACE_DESC_SIZE, /* bLength */
USB_DESC_TYPE_INTERFACE, /* bDescriptorType */
0x01, /* bInterfaceNumber */
0x01, /* bAlternateSetting */
0x01, /* bNumEndpoints */
USB_DEVICE_CLASS_AUDIO, /* bInterfaceClass */
AUDIO_SUBCLASS_AUDIOSTREAMING, /* bInterfaceSubClass */
AUDIO_PROTOCOL_UNDEFINED, /* bInterfaceProtocol */
0x00, /* iInterface */
/* 09 byte*/
/* USB Microphone Audio Streaming Interface Descriptor */
AUDIO_STREAMING_INTERFACE_DESC_SIZE, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_STREAMING_GENERAL, /* bDescriptorSubtype */
AUDIO_PORT_OUTPUT_TERMINAL_ID_3, /* bTerminalLink */
0x01, /* bDelay */
0x01, /* wFormatTag AUDIO_FORMAT_PCM 0x0001 */
0x00,
/* 07 byte*/
/* USB Microphone Audio Type III Format Interface Descriptor */
0x0B, /* bLength */
AUDIO_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_STREAMING_FORMAT_TYPE, /* bDescriptorSubtype */
AUDIO_FORMAT_TYPE_I, /* bFormatType */
AUDIO_PORT_CHANNEL_NUMS, /* bNrChannels */
0x02, /* bSubFrameSize : 2 Bytes per frame (16bits) */
16, /* bBitResolution (16-bits per sample) */
0x01, /* bSamFreqType only one frequency supported */
AUDIO_SAMPLE_FREQ(USBD_AUDIO_FREQ), /* Audio sampling frequency coded on 3 bytes */
/* 11 byte*/
/* Endpoint 1 - Standard Descriptor */
AUDIO_STANDARD_ENDPOINT_DESC_SIZE, /* bLength */
USB_DESC_TYPE_ENDPOINT, /* bDescriptorType */
AUDIO_PORT_IN_EP_DIR_ID, /* bEndpointAddress 1 in endpoint */
USBD_EP_TYPE_ISOC, /* bmAttributes */
AUDIO_PORT_PACKET_SZE(USBD_AUDIO_FREQ),/* wMaxPacketSize in Bytes (Freq(Samples)*2(Stereo)*2(HalfWord)) */
AUDIO_PORT_FS_BINTERVAL, /* bInterval */
0x00, /* bRefresh */
0x00, /* bSynchAddress */
/* 09 byte*/
/* Endpoint - Audio Streaming Descriptor*/
AUDIO_STREAMING_ENDPOINT_DESC_SIZE, /* bLength */
AUDIO_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType */
AUDIO_ENDPOINT_GENERAL, /* bDescriptor */
0x00, /* bmAttributes */
0x00, /* bLockDelayUnits */
0x00, /* wLockDelay */
0x00,
/* 07 byte*/
} ;
/* USB Standard Device Descriptor */
__ALIGN_BEGIN static uint8_t USBD_AUDIO_DeviceQualifierDesc[USB_LEN_DEV_QUALIFIER_DESC] __ALIGN_END =
{
USB_LEN_DEV_QUALIFIER_DESC,
USB_DESC_TYPE_DEVICE_QUALIFIER,
0x00,
0x02,
0x00,
0x00,
0x00,
0x40,
0x01,
0x00,
};
/**
* @}
*/
/** @defgroup USBD_AUDIO_Private_Functions
* @{
*/
/**
* @brief USBD_AUDIO_Init
* Initialize the AUDIO interface
* @param pdev: device instance
* @param cfgidx: Configuration index
* @retval status
*/
static uint8_t USBD_AUDIO_Init(USBD_HandleTypeDef *pdev, uint8_t cfgidx)
{
return USB_Audio_Port_EP_IN_Init(pdev, cfgidx);
}
/**
* @brief USBD_AUDIO_Init
* DeInitialize the AUDIO layer
* @param pdev: device instance
* @param cfgidx: Configuration index
* @retval status
*/
static uint8_t USBD_AUDIO_DeInit(USBD_HandleTypeDef *pdev, uint8_t cfgidx)
{
UNUSED(cfgidx);
/* Open EP OUT */
(void)USBD_LL_CloseEP(pdev, AUDIO_OUT_EP);
pdev->ep_out[AUDIO_OUT_EP & 0xFU].is_used = 0U;
pdev->ep_out[AUDIO_OUT_EP & 0xFU].bInterval = 0U;
/* DeInit physical Interface components */
if (pdev->pClassData != NULL)
{
((USBD_AUDIO_ItfTypeDef *)pdev->pUserData)->DeInit(0U);
(void)USBD_free(pdev->pClassData);
pdev->pClassData = NULL;
}
return (uint8_t)USBD_OK;
}
/**
* @brief USBD_AUDIO_Setup
* Handle the AUDIO specific requests
* @param pdev: instance
* @param req: usb requests
* @retval status
*/
static uint8_t USBD_AUDIO_Setup(USBD_HandleTypeDef *pdev,
USBD_SetupReqTypedef *req)
{
USBD_AUDIO_HandleTypeDef *haudio;
uint16_t len;
uint8_t *pbuf;
uint16_t status_info = 0U;
USBD_StatusTypeDef ret = USBD_OK;
haudio = (USBD_AUDIO_HandleTypeDef *)pdev->pClassData;
if (haudio == NULL)
{
return (uint8_t)USBD_FAIL;
}
switch (req->bmRequest & USB_REQ_TYPE_MASK)
{
case USB_REQ_TYPE_CLASS:
switch (req->bRequest)
{
case AUDIO_REQ_GET_CUR:
AUDIO_REQ_GetCurrent(pdev, req);
break;
case AUDIO_REQ_SET_CUR:
AUDIO_REQ_SetCurrent(pdev, req);
break;
default:
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
break;
}
break;
case USB_REQ_TYPE_STANDARD:
switch (req->bRequest)
{
case USB_REQ_GET_STATUS:
if (pdev->dev_state == USBD_STATE_CONFIGURED)
{
(void)USBD_CtlSendData(pdev, (uint8_t *)&status_info, 2U);
}
else
{
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
}
break;
case USB_REQ_GET_DESCRIPTOR:
if ((req->wValue >> 8) == AUDIO_DESCRIPTOR_TYPE)
{
pbuf = USBD_AUDIO_CfgDesc + 18;
len = MIN(USB_AUDIO_DESC_SIZ, req->wLength);
(void)USBD_CtlSendData(pdev, pbuf, len);
}
break;
case USB_REQ_GET_INTERFACE:
if (pdev->dev_state == USBD_STATE_CONFIGURED)
{
(void)USBD_CtlSendData(pdev, (uint8_t *)&haudio->alt_setting, 1U);
}
else
{
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
}
break;
case USB_REQ_SET_INTERFACE:
if (pdev->dev_state == USBD_STATE_CONFIGURED)
{
if ((uint8_t)(req->wValue) <= USBD_MAX_NUM_INTERFACES)
{
haudio->alt_setting = (uint8_t)(req->wValue);
}
else
{
/* Call the error management function (command will be NAKed */
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
}
}
else
{
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
}
break;
case USB_REQ_CLEAR_FEATURE:
break;
default:
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
break;
}
break;
default:
USBD_CtlError(pdev, req);
ret = USBD_FAIL;
break;
}
return (uint8_t)ret;
}
/**
* @brief USBD_AUDIO_GetCfgDesc
* return configuration descriptor
* @param speed : current device speed
* @param length : pointer data length
* @retval pointer to descriptor buffer
*/
static uint8_t *USBD_AUDIO_GetCfgDesc(uint16_t *length)
{
*length = (uint16_t)sizeof(USBD_AUDIO_CfgDesc);
return USBD_AUDIO_CfgDesc;
}
/**
* @brief USBD_AUDIO_DataIn
* handle data IN Stage
* @param pdev: device instance
* @param epnum: endpoint index
* @retval status
*/
static uint8_t USBD_AUDIO_DataIn(USBD_HandleTypeDef *pdev, uint8_t epnum)
{
return USB_Audio_Port_DataIn(pdev, epnum);
}
/**
* @brief USBD_AUDIO_EP0_RxReady
* handle EP0 Rx Ready event
* @param pdev: device instance
* @retval status
*/
static uint8_t USBD_AUDIO_EP0_RxReady(USBD_HandleTypeDef *pdev)
{
USBD_AUDIO_HandleTypeDef *haudio;
haudio = (USBD_AUDIO_HandleTypeDef *)pdev->pClassData;
if (haudio == NULL)
{
return (uint8_t)USBD_FAIL;
}
if (haudio->control.cmd == AUDIO_REQ_SET_CUR)
{
/* In this driver, to simplify code, only SET_CUR request is managed */
if (haudio->control.unit == AUDIO_OUT_STREAMING_CTRL)
{
((USBD_AUDIO_ItfTypeDef *)pdev->pUserData)->MuteCtl(haudio->control.data[0]);
haudio->control.cmd = 0U;
haudio->control.len = 0U;
}
}
return (uint8_t)USBD_OK;
}
/**
* @brief USBD_AUDIO_EP0_TxReady
* handle EP0 TRx Ready event
* @param pdev: device instance
* @retval status
*/
static uint8_t USBD_AUDIO_EP0_TxReady(USBD_HandleTypeDef *pdev)
{
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