Merge pull request #938 from HiFiPhile/uac_example

Bug fix and Enhancements of UAC2

examples/device/uac2_headset/src/main.c

@@ -34,9 +34,11 @@
 // MACRO CONSTANT TYPEDEF PROTOTYPES
 //--------------------------------------------------------------------+
 
-#ifndef AUDIO_SAMPLE_RATE
-#define AUDIO_SAMPLE_RATE     48000
-#endif
+// List of supported sample rates
+const uint32_t sample_rates[]       = {44100, 48000, 88200, 96000};
+uint32_t       current_sample_rate  = 44100;
+
+#define N_SAMPLE_RATES  TU_ARRAY_SIZE(sample_rates)
 
 /* Blink pattern
  * - 25 ms   : streaming data
@@ -76,11 +78,16 @@ int8_t mute[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX + 1];       // +1 for master chan
 int16_t volume[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX + 1];    // +1 for master channel 0
 
 // Buffer for microphone data
-int16_t mic_buf[1000];
+int32_t mic_buf[CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ / 4];
 // Buffer for speaker data
-int16_t spk_buf[1000];
+int32_t spk_buf[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ / 4];
 // Speaker data size received in the last frame
 int spk_data_size;
+// Resolution per format
+const uint8_t resolutions_per_format[CFG_TUD_AUDIO_FUNC_1_N_FORMATS] = {CFG_TUD_AUDIO_FUNC_1_FORMAT_1_RESOLUTION_RX,
+                                                                        CFG_TUD_AUDIO_FUNC_1_FORMAT_2_RESOLUTION_RX};
+// Current resolution, update on format change
+uint8_t current_resolution;
 
 void led_blinking_task(void);
 void audio_task(void);
@@ -135,55 +142,35 @@ void tud_resume_cb(void)
   blink_interval_ms = BLINK_MOUNTED;
 }
 
-typedef struct TU_ATTR_PACKED
-{
-  union
-  {
-    struct TU_ATTR_PACKED
-    {
-      uint8_t recipient :  5; ///< Recipient type tusb_request_recipient_t.
-      uint8_t type      :  2; ///< Request type tusb_request_type_t.
-      uint8_t direction :  1; ///< Direction type. tusb_dir_t
-    } bmRequestType_bit;
-
-    uint8_t bmRequestType;
-  };
-
-  uint8_t bRequest;  ///< Request type audio_cs_req_t
-  uint8_t bChannelNumber;
-  uint8_t bControlSelector;
-  union
-  {
-    uint8_t bInterface;
-    uint8_t bEndpoint;
-  };
-  uint8_t bEntityID;
-  uint16_t wLength;
-} audio_control_request_t;
-
 // Helper for clock get requests
 static bool tud_audio_clock_get_request(uint8_t rhport, audio_control_request_t const *request)
 {
   TU_ASSERT(request->bEntityID == UAC2_ENTITY_CLOCK);
 
-  // Example supports only single frequency, same value will be used for current value and range
   if (request->bControlSelector == AUDIO_CS_CTRL_SAM_FREQ)
   {
     if (request->bRequest == AUDIO_CS_REQ_CUR)
     {
-      TU_LOG2("Clock get current freq %u\r\n", AUDIO_SAMPLE_RATE);
+      TU_LOG1("Clock get current freq %u\r\n", current_sample_rate);
 
-      audio_control_cur_4_t curf = { tu_htole32(AUDIO_SAMPLE_RATE) };
+      audio_control_cur_4_t curf = { tu_htole32(current_sample_rate) };
       return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &curf, sizeof(curf));
     }
     else if (request->bRequest == AUDIO_CS_REQ_RANGE)
     {
-      audio_control_range_4_n_t(1) rangef =
+      audio_control_range_4_n_t(N_SAMPLE_RATES) rangef =
       {
-        .wNumSubRanges = tu_htole16(1),
-        .subrange[0] = { tu_htole32(AUDIO_SAMPLE_RATE), tu_htole32(AUDIO_SAMPLE_RATE), 0}
+        .wNumSubRanges = tu_htole16(N_SAMPLE_RATES)
       };
-      TU_LOG2("Clock get freq range (%d, %d, %d)\r\n", (int)rangef.subrange[0].bMin, (int)rangef.subrange[0].bMax, (int)rangef.subrange[0].bRes);
+      TU_LOG1("Clock get %d freq ranges\r\n", N_SAMPLE_RATES);
+      for(uint8_t i = 0; i < N_SAMPLE_RATES; i++)
+      {
+        rangef.subrange[i].bMin = sample_rates[i];
+        rangef.subrange[i].bMax = sample_rates[i];
+        rangef.subrange[i].bRes = 0;
+        TU_LOG1("Range %d (%d, %d, %d)\r\n", i, (int)rangef.subrange[i].bMin, (int)rangef.subrange[i].bMax, (int)rangef.subrange[i].bRes);
+      }
+      
       return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &rangef, sizeof(rangef));
     }
   }
@@ -191,7 +178,7 @@ static bool tud_audio_clock_get_request(uint8_t rhport, audio_control_request_t
            request->bRequest == AUDIO_CS_REQ_CUR)
   {
     audio_control_cur_1_t cur_valid = { .bCur = 1 };
-    TU_LOG2("Clock get is valid %u\r\n", cur_valid.bCur);
+    TU_LOG1("Clock get is valid %u\r\n", cur_valid.bCur);
     return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &cur_valid, sizeof(cur_valid));
   }
   TU_LOG1("Clock get request not supported, entity = %u, selector = %u, request = %u\r\n",
@@ -199,6 +186,32 @@ static bool tud_audio_clock_get_request(uint8_t rhport, audio_control_request_t
   return false;
 }
 
+// Helper for clock set requests
+static bool tud_audio_clock_set_request(uint8_t rhport, audio_control_request_t const *request, uint8_t const *buf)
+{
+  (void)rhport;
+
+  TU_ASSERT(request->bEntityID == UAC2_ENTITY_CLOCK);
+  TU_VERIFY(request->bRequest == AUDIO_CS_REQ_CUR);
+
+  if (request->bControlSelector == AUDIO_CS_CTRL_SAM_FREQ)
+  {
+    TU_VERIFY(request->wLength == sizeof(audio_control_cur_4_t));
+
+    current_sample_rate = ((audio_control_cur_4_t *)buf)->bCur;
+
+    TU_LOG1("Clock set current freq: %d\r\n", current_sample_rate);
+
+    return true;
+  }
+  else
+  {
+    TU_LOG1("Clock set request not supported, entity = %u, selector = %u, request = %u\r\n",
+            request->bEntityID, request->bControlSelector, request->bRequest);
+    return false;
+  }
+}
+
 // Helper for feature unit get requests
 static bool tud_audio_feature_unit_get_request(uint8_t rhport, audio_control_request_t const *request)
 {
@@ -207,7 +220,7 @@ static bool tud_audio_feature_unit_get_request(uint8_t rhport, audio_control_req
   if (request->bControlSelector == AUDIO_FU_CTRL_MUTE && request->bRequest == AUDIO_CS_REQ_CUR)
   {
     audio_control_cur_1_t mute1 = { .bCur = mute[request->bChannelNumber] };
-    TU_LOG2("Get channel %u mute %d\r\n", request->bChannelNumber, mute1.bCur);
+    TU_LOG1("Get channel %u mute %d\r\n", request->bChannelNumber, mute1.bCur);
     return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &mute1, sizeof(mute1));
   }
   else if (UAC2_ENTITY_SPK_FEATURE_UNIT && request->bControlSelector == AUDIO_FU_CTRL_VOLUME)
@@ -218,14 +231,14 @@ static bool tud_audio_feature_unit_get_request(uint8_t rhport, audio_control_req
         .wNumSubRanges = tu_htole16(1),
         .subrange[0] = { .bMin = tu_htole16(-VOLUME_CTRL_50_DB), tu_htole16(VOLUME_CTRL_0_DB), tu_htole16(256) }
       };
-      TU_LOG2("Get channel %u volume range (%d, %d, %u) dB\r\n", request->bChannelNumber,
+      TU_LOG1("Get channel %u volume range (%d, %d, %u) dB\r\n", request->bChannelNumber,
               range_vol.subrange[0].bMin / 256, range_vol.subrange[0].bMax / 256, range_vol.subrange[0].bRes / 256);
       return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &range_vol, sizeof(range_vol));
     }
     else if (request->bRequest == AUDIO_CS_REQ_CUR)
     {
       audio_control_cur_2_t cur_vol = { .bCur = tu_htole16(volume[request->bChannelNumber]) };
-      TU_LOG2("Get channel %u volume %u dB\r\n", request->bChannelNumber, cur_vol.bCur);
+      TU_LOG1("Get channel %u volume %d dB\r\n", request->bChannelNumber, cur_vol.bCur / 256);
       return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &cur_vol, sizeof(cur_vol));
     }
   }
@@ -249,7 +262,7 @@ static bool tud_audio_feature_unit_set_request(uint8_t rhport, audio_control_req
 
     mute[request->bChannelNumber] = ((audio_control_cur_1_t *)buf)->bCur;
 
-    TU_LOG2("Set channel %d Mute: %d\r\n", request->bChannelNumber, mute[request->bChannelNumber]);
+    TU_LOG1("Set channel %d Mute: %d\r\n", request->bChannelNumber, mute[request->bChannelNumber]);
 
     return true;
   }
@@ -259,7 +272,7 @@ static bool tud_audio_feature_unit_set_request(uint8_t rhport, audio_control_req
 
     volume[request->bChannelNumber] = ((audio_control_cur_2_t const *)buf)->bCur;
 
-    TU_LOG2("Set channel %d volume: %d dB\r\n", request->bChannelNumber, volume[request->bChannelNumber] / 256);
+    TU_LOG1("Set channel %d volume: %d dB\r\n", request->bChannelNumber, volume[request->bChannelNumber] / 256);
 
     return true;
   }
@@ -299,7 +312,8 @@ bool tud_audio_set_req_entity_cb(uint8_t rhport, tusb_control_request_t const *p
 
   if (request->bEntityID == UAC2_ENTITY_SPK_FEATURE_UNIT)
     return tud_audio_feature_unit_set_request(rhport, request, buf);
-
+  if (request->bEntityID == UAC2_ENTITY_CLOCK)
+    return tud_audio_clock_set_request(rhport, request, buf);
   TU_LOG1("Set request not handled, entity = %d, selector = %d, request = %d\r\n",
           request->bEntityID, request->bControlSelector, request->bRequest);
 
@@ -329,6 +343,13 @@ bool tud_audio_set_itf_cb(uint8_t rhport, tusb_control_request_t const * p_reque
   if (ITF_NUM_AUDIO_STREAMING_SPK == itf && alt != 0)
       blink_interval_ms = BLINK_STREAMING;
 
+  // Clear buffer when streaming format is changed
+  spk_data_size = 0;
+  if(alt != 0)
+  {
+    current_resolution = resolutions_per_format[alt-1];
+  }
+
   return true;
 }
 
@@ -362,20 +383,40 @@ void audio_task(void)
 {
   // When new data arrived, copy data from speaker buffer, to microphone buffer
   // and send it over
+  // Only support speaker & headphone both have the same resolution
+  // If one is 16bit another is 24bit be care of LOUD noise !
   if (spk_data_size)
   {
-    int16_t *src = spk_buf;
-    int16_t *limit = spk_buf + spk_data_size / 2;
-    int16_t *dst = mic_buf;
-    while (src < limit)
+    if (current_resolution == 16)
     {
-      // Combine two channels into one
-      int32_t left = *src++;
-      int32_t right = *src++;
-      *dst++ = (int16_t)((left + right) / 2);
+      int16_t *src = (int16_t*)spk_buf;
+      int16_t *limit = (int16_t*)spk_buf + spk_data_size / 2;
+      int16_t *dst = (int16_t*)mic_buf;
+      while (src < limit)
+      {
+        // Combine two channels into one
+        int32_t left = *src++;
+        int32_t right = *src++;
+        *dst++ = (left >> 1) + (right >> 1);
+      }
+      tud_audio_write((uint8_t *)mic_buf, spk_data_size / 2);
+      spk_data_size = 0;
+    }
+    else if (current_resolution == 24)
+    {
+      int32_t *src = spk_buf;
+      int32_t *limit = spk_buf + spk_data_size / 4;
+      int32_t *dst = mic_buf;
+      while (src < limit)
+      {
+        // Combine two channels into one
+        int32_t left = *src++;
+        int32_t right = *src++;
+        *dst++ = ((left >> 1) + (right >> 1)) & 0xffffff00;
+      }
+      tud_audio_write((uint8_t *)mic_buf, spk_data_size / 2);
+      spk_data_size = 0;
     }
-    tud_audio_write((uint8_t *)mic_buf, spk_data_size / 2);
-    spk_data_size = 0;
   }
 }
 

examples/device/uac2_headset/src/tusb_config.h

@@ -93,33 +93,49 @@ extern "C" {
 //--------------------------------------------------------------------
 // AUDIO CLASS DRIVER CONFIGURATION
 //--------------------------------------------------------------------
-#define CFG_TUD_AUDIO_IN_PATH                     (CFG_TUD_AUDIO)
-#define CFG_TUD_AUDIO_OUT_PATH                    (CFG_TUD_AUDIO)
 
-//#define CFG_TUD_AUDIO_FUNC_1_DESC_LEN                       220       // This equals TUD_AUDIO_HEADSET_STEREO_DESC_LEN, however, including it from usb_descriptors.h is not possible due to some strange include hassle
-#define CFG_TUD_AUDIO_FUNC_1_DESC_LEN                       TUD_AUDIO_HEADSET_STEREO_DESC_LEN
+#define CFG_TUD_AUDIO_FUNC_1_DESC_LEN                                TUD_AUDIO_HEADSET_STEREO_DESC_LEN
+
+// How many formats are used, need to adjust USB descriptor if changed
+#define CFG_TUD_AUDIO_FUNC_1_N_FORMATS                               2
 
 // Audio format type I specifications
-#define CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX                  1
-#define CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX          2
-#define CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX                  2
-#define CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_RX          2
-#define CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP                    0
+#define CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE                         96000     // 24bit/96kHz is the best quality for full-speed, high-speed is needed beyond this
+#define CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX                           1
+#define CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX                           2
+
+// 16bit in 16bit slots
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_TX          2
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_1_RESOLUTION_TX                  16
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_RX          2
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_1_RESOLUTION_RX                  16
+
+// 24bit in 32bit slots
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_TX          4
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_2_RESOLUTION_TX                  24
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_RX          4
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_2_RESOLUTION_RX                  24
 
 // EP and buffer size - for isochronous EP´s, the buffer and EP size are equal (different sizes would not make sense)
 #define CFG_TUD_AUDIO_ENABLE_EP_IN                1
-#define CFG_TUD_AUDIO_EP_SZ_IN                    (CFG_TUD_AUDIO_IN_PATH * (48 + 1) * (CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX) * (CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX)) // 48 Samples (48 kHz) x 2 Bytes/Sample x n Channels
-#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ      CFG_TUD_AUDIO_EP_SZ_IN
-#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX         CFG_TUD_AUDIO_EP_SZ_IN                  // Maximum EP IN size for all AS alternate settings used
+
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_1_EP_SZ_IN    TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX)
+#define CFG_TUD_AUDIO_FUNC_1_FORMAT_2_EP_SZ_IN    TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX)
+
+#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ      TU_MAX(CFG_TUD_AUDIO_FUNC_1_FORMAT_1_EP_SZ_IN, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_EP_SZ_IN)*2
+#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX         TU_MAX(CFG_TUD_AUDIO_FUNC_1_FORMAT_1_EP_SZ_IN, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_EP_SZ_IN) // Maximum EP IN size for all AS alternate settings used
 
 // EP and buffer size - for isochronous EP´s, the buffer and EP size are equal (different sizes would not make sense)
 #define CFG_TUD_AUDIO_ENABLE_EP_OUT               1
-#define CFG_TUD_AUDIO_EP_OUT_SZ                   (CFG_TUD_AUDIO_OUT_PATH * ((48 + CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP) * (CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_RX) * (CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX))) // N Samples (N kHz) x 2 Bytes/Sample x n Channels
-#define CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ     CFG_TUD_AUDIO_EP_OUT_SZ*3
-#define CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX        CFG_TUD_AUDIO_EP_OUT_SZ                 // Maximum EP IN size for all AS alternate settings used
+
+#define CFG_TUD_AUDIO_UNC_1_FORMAT_1_EP_SZ_OUT    TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX)
+#define CFG_TUD_AUDIO_UNC_1_FORMAT_2_EP_SZ_OUT    TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX)
+
+#define CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ     TU_MAX(CFG_TUD_AUDIO_UNC_1_FORMAT_1_EP_SZ_OUT, CFG_TUD_AUDIO_UNC_1_FORMAT_2_EP_SZ_OUT)*2
+#define CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX        TU_MAX(CFG_TUD_AUDIO_UNC_1_FORMAT_1_EP_SZ_OUT, CFG_TUD_AUDIO_UNC_1_FORMAT_2_EP_SZ_OUT) // Maximum EP IN size for all AS alternate settings used
 
 // Number of Standard AS Interface Descriptors (4.9.1) defined per audio function - this is required to be able to remember the current alternate settings of these interfaces - We restrict us here to have a constant number for all audio functions (which means this has to be the maximum number of AS interfaces an audio function has and a second audio function with less AS interfaces just wastes a few bytes)
-#define CFG_TUD_AUDIO_FUNC_1_N_AS_INT 	          1
+#define CFG_TUD_AUDIO_FUNC_1_N_AS_INT 	          2
 
 // Size of control request buffer
 #define CFG_TUD_AUDIO_FUNC_1_CTRL_BUF_SZ	64

examples/device/uac2_headset/src/usb_descriptors.c

@@ -93,7 +93,7 @@ uint8_t const desc_configuration[] =
     TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100),
 
     // Interface number, string index, EP Out & EP In address, EP size
-    TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(2, 2, 16, EPNUM_AUDIO, CFG_TUD_AUDIO_EP_OUT_SZ, EPNUM_AUDIO | 0x80, CFG_TUD_AUDIO_EP_SZ_IN)
+    TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(2, EPNUM_AUDIO, EPNUM_AUDIO | 0x80)
 };
 
 // Invoked when received GET CONFIGURATION DESCRIPTOR

examples/device/uac2_headset/src/usb_descriptors.h

@@ -55,21 +55,36 @@ enum
     + TUD_AUDIO_DESC_OUTPUT_TERM_LEN\
     + TUD_AUDIO_DESC_INPUT_TERM_LEN\
     + TUD_AUDIO_DESC_OUTPUT_TERM_LEN\
+    /* Interface 1, Alternate 0 */\
     + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    /* Interface 1, Alternate 0 */\
     + TUD_AUDIO_DESC_STD_AS_INT_LEN\
     + TUD_AUDIO_DESC_CS_AS_INT_LEN\
     + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
     + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
     + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN\
+    /* Interface 1, Alternate 2 */\
     + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_CS_AS_INT_LEN\
+    + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
+    + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN\
+    /* Interface 2, Alternate 0 */\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    /* Interface 2, Alternate 1 */\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_CS_AS_INT_LEN\
+    + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
+    + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN\
+    /* Interface 2, Alternate 2 */\
     + TUD_AUDIO_DESC_STD_AS_INT_LEN\
     + TUD_AUDIO_DESC_CS_AS_INT_LEN\
     + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
     + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
     + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN)
 
-
-#define TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(_stridx, _nBytesPerSample, _nBitsUsedPerSample, _epout, _epoutsize, _epin, _epinsize) \
+#define TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(_stridx, _epout, _epin) \
     /* Standard Interface Association Descriptor (IAD) */\
     TUD_AUDIO_DESC_IAD(/*_firstitfs*/ ITF_NUM_AUDIO_CONTROL, /*_nitfs*/ ITF_NUM_TOTAL, /*_stridx*/ 0x00),\
     /* Standard AC Interface Descriptor(4.7.1) */\
@@ -77,13 +92,13 @@ enum
     /* Class-Specific AC Interface Header Descriptor(4.7.2) */\
     TUD_AUDIO_DESC_CS_AC(/*_bcdADC*/ 0x0200, /*_category*/ AUDIO_FUNC_HEADSET, /*_totallen*/ TUD_AUDIO_DESC_CLK_SRC_LEN+TUD_AUDIO_DESC_FEATURE_UNIT_TWO_CHANNEL_LEN+TUD_AUDIO_DESC_INPUT_TERM_LEN+TUD_AUDIO_DESC_OUTPUT_TERM_LEN+TUD_AUDIO_DESC_INPUT_TERM_LEN+TUD_AUDIO_DESC_OUTPUT_TERM_LEN, /*_ctrl*/ AUDIO_CS_AS_INTERFACE_CTRL_LATENCY_POS),\
     /* Clock Source Descriptor(4.7.2.1) */\
-    TUD_AUDIO_DESC_CLK_SRC(/*_clkid*/ UAC2_ENTITY_CLOCK, /*_attr*/ 3, /*_ctrl*/ 5, /*_assocTerm*/ 0x00,  /*_stridx*/ 0x00),    \
+    TUD_AUDIO_DESC_CLK_SRC(/*_clkid*/ UAC2_ENTITY_CLOCK, /*_attr*/ 3, /*_ctrl*/ 7, /*_assocTerm*/ 0x00,  /*_stridx*/ 0x00),    \
     /* Input Terminal Descriptor(4.7.2.4) */\
     TUD_AUDIO_DESC_INPUT_TERM(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_USB_STREAMING, /*_assocTerm*/ 0x00, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_nchannelslogical*/ 0x02, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_idxchannelnames*/ 0x00, /*_ctrl*/ 0 * (AUDIO_CTRL_R << AUDIO_IN_TERM_CTRL_CONNECTOR_POS), /*_stridx*/ 0x00),\
     /* Feature Unit Descriptor(4.7.2.8) */\
     TUD_AUDIO_DESC_FEATURE_UNIT_TWO_CHANNEL(/*_unitid*/ UAC2_ENTITY_SPK_FEATURE_UNIT, /*_srcid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrlch0master*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_ctrlch1*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_ctrlch2*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_stridx*/ 0x00),\
     /* Output Terminal Descriptor(4.7.2.5) */\
-    TUD_AUDIO_DESC_OUTPUT_TERM(/*_termid*/ UAC2_ENTITY_SPK_OUTPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_OUT_GENERIC_SPEAKER, /*_assocTerm*/ 0x00, /*_srcid*/ UAC2_ENTITY_SPK_FEATURE_UNIT, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_ctrl*/ 0x0000, /*_stridx*/ 0x00),\
+    TUD_AUDIO_DESC_OUTPUT_TERM(/*_termid*/ UAC2_ENTITY_SPK_OUTPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_OUT_HEADPHONES, /*_assocTerm*/ 0x00, /*_srcid*/ UAC2_ENTITY_SPK_FEATURE_UNIT, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_ctrl*/ 0x0000, /*_stridx*/ 0x00),\
     /* Input Terminal Descriptor(4.7.2.4) */\
     TUD_AUDIO_DESC_INPUT_TERM(/*_termid*/ UAC2_ENTITY_MIC_INPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_IN_GENERIC_MIC, /*_assocTerm*/ 0x00, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_nchannelslogical*/ 0x01, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_idxchannelnames*/ 0x00, /*_ctrl*/ 0 * (AUDIO_CTRL_R << AUDIO_IN_TERM_CTRL_CONNECTOR_POS), /*_stridx*/ 0x00),\
     /* Output Terminal Descriptor(4.7.2.5) */\
@@ -95,26 +110,46 @@ enum
     /* Interface 1, Alternate 1 - alternate interface for data streaming */\
     TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_SPK), /*_altset*/ 0x01, /*_nEPs*/ 0x01, /*_stridx*/ 0x05),\
     /* Class-Specific AS Interface Descriptor(4.9.2) */\
-    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ 0x02, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
     /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
-    TUD_AUDIO_DESC_TYPE_I_FORMAT(_nBytesPerSample, _nBitsUsedPerSample),\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_RESOLUTION_RX),\
     /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
-    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epout, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ADAPTIVE | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ _epoutsize, /*_interval*/ (CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 0x04 : 0x01),\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epout, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ADAPTIVE | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX), /*_interval*/ 0x01),\
+    /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
+    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_MILLISEC, /*_lockdelay*/ 0x0001),\
+    /* Interface 1, Alternate 2 - alternate interface for data streaming */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_SPK), /*_altset*/ 0x02, /*_nEPs*/ 0x01, /*_stridx*/ 0x05),\
+    /* Class-Specific AS Interface Descriptor(4.9.2) */\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_RESOLUTION_RX),\
+    /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epout, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ADAPTIVE | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_RX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX), /*_interval*/ 0x01),\
     /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
     TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_MILLISEC, /*_lockdelay*/ 0x0001),\
     /* Standard AS Interface Descriptor(4.9.1) */\
     /* Interface 2, Alternate 0 - default alternate setting with 0 bandwidth */\
     TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_MIC), /*_altset*/ 0x00, /*_nEPs*/ 0x00, /*_stridx*/ 0x04),\
     /* Standard AS Interface Descriptor(4.9.1) */\
-    /* Interface 1, Alternate 1 - alternate interface for data streaming */\
+    /* Interface 2, Alternate 1 - alternate interface for data streaming */\
     TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_MIC), /*_altset*/ 0x01, /*_nEPs*/ 0x01, /*_stridx*/ 0x04),\
     /* Class-Specific AS Interface Descriptor(4.9.2) */\
-    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_MIC_OUTPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ 0x01, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_MIC_OUTPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_RESOLUTION_TX),\
+    /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epin, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ASYNCHRONOUS | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_1_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX), /*_interval*/ 0x01),\
+    /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
+    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_UNDEFINED, /*_lockdelay*/ 0x0000),\
+    /* Interface 2, Alternate 2 - alternate interface for data streaming */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_MIC), /*_altset*/ 0x02, /*_nEPs*/ 0x01, /*_stridx*/ 0x04),\
+    /* Class-Specific AS Interface Descriptor(4.9.2) */\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_MIC_OUTPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
     /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
-    TUD_AUDIO_DESC_TYPE_I_FORMAT(_nBytesPerSample, _nBitsUsedPerSample),\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_RESOLUTION_TX),\
     /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
-    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epin, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ASYNCHRONOUS | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ _epinsize, /*_interval*/ (CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 0x04 : 0x01),\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epin, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ASYNCHRONOUS | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ TUD_AUDIO_EP_SIZE(CFG_TUD_AUDIO_FUNC_1_MAX_SAMPLE_RATE, CFG_TUD_AUDIO_FUNC_1_FORMAT_2_N_BYTES_PER_SAMPLE_TX, CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX), /*_interval*/ 0x01),\
     /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
-    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_UNDEFINED, /*_lockdelay*/ 0x0000)\
+    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_UNDEFINED, /*_lockdelay*/ 0x0000)
 
 #endif

src/class/audio/audio.h

@@ -489,7 +489,7 @@ typedef enum
   AUDIO_DATA_FORMAT_TYPE_I_IEEE_FLOAT     = (uint32_t) (1 << 2),
   AUDIO_DATA_FORMAT_TYPE_I_ALAW           = (uint32_t) (1 << 3),
   AUDIO_DATA_FORMAT_TYPE_I_MULAW          = (uint32_t) (1 << 4),
-  AUDIO_DATA_FORMAT_TYPE_I_RAW_DATA       = 0x100000000,
+  AUDIO_DATA_FORMAT_TYPE_I_RAW_DATA       = 0x80000000,
 } audio_data_format_type_I_t;
 
 /// All remaining definitions are taken from the descriptor descriptions in the UAC2 main specification
@@ -823,6 +823,33 @@ typedef struct TU_ATTR_PACKED
   uint16_t wLockDelay        ; ///< Indicates the time it takes this endpoint to reliably lock its internal clock recovery circuitry. Units used depend on the value of the bLockDelayUnits field.
 } audio_desc_cs_as_iso_data_ep_t;
 
+// 5.2.2 Control Request Layout
+typedef struct TU_ATTR_PACKED
+{
+    union
+    {
+        struct TU_ATTR_PACKED
+        {
+            uint8_t recipient :  5; ///< Recipient type tusb_request_recipient_t.
+            uint8_t type      :  2; ///< Request type tusb_request_type_t.
+            uint8_t direction :  1; ///< Direction type. tusb_dir_t
+        } bmRequestType_bit;
+        
+        uint8_t bmRequestType;
+    };
+    
+    uint8_t bRequest;  ///< Request type audio_cs_req_t
+    uint8_t bChannelNumber;
+    uint8_t bControlSelector;
+    union
+    {
+        uint8_t bInterface;
+        uint8_t bEndpoint;
+    };
+    uint8_t bEntityID;
+    uint16_t wLength;
+} audio_control_request_t;
+
 //// 5.2.3 Control Request Parameter Block Layout
 
 // 5.2.3.1 1-byte Control CUR Parameter Block

src/class/audio/audio_device.c

@@ -102,19 +102,19 @@
 // EP IN software buffers and mutexes
 #if CFG_TUD_AUDIO_ENABLE_EP_IN && !CFG_TUD_AUDIO_ENABLE_ENCODING
 #if CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_1[CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_1[CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_in_ff_mutex_wr_1;                                                             // No need for read mutex as only USB driver reads from FIFO
 #endif
 #endif // CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ > 0
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_IN_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_2[CFG_TUD_AUDIO_FUNC_2_EP_IN_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_2[CFG_TUD_AUDIO_FUNC_2_EP_IN_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_in_ff_mutex_wr_2;                                                             // No need for read mutex as only USB driver reads from FIFO
 #endif
 #endif // CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_IN_SW_BUF_SZ > 0
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_EP_IN_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_3[CFG_TUD_AUDIO_FUNC_3_EP_IN_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_in_sw_buf_3[CFG_TUD_AUDIO_FUNC_3_EP_IN_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_in_ff_mutex_wr_3;                                                             // No need for read mutex as only USB driver reads from FIFO
 #endif
@@ -126,32 +126,32 @@ osal_mutex_def_t ep_in_ff_mutex_wr_3;
 // - the software encoding is used - in this case the linear buffers serve as a target memory where logical channels are encoded into
 #if CFG_TUD_AUDIO_ENABLE_EP_IN && (USE_LINEAR_BUFFER || CFG_TUD_AUDIO_ENABLE_ENCODING)
 #if CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_1[CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_1[CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX];
 #endif
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_IN_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_2[CFG_TUD_AUDIO_FUNC_2_EP_IN_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_2[CFG_TUD_AUDIO_FUNC_2_EP_IN_SZ_MAX];
 #endif
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_EP_IN_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_3[CFG_TUD_AUDIO_FUNC_3_EP_IN_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_in_3[CFG_TUD_AUDIO_FUNC_3_EP_IN_SZ_MAX];
 #endif
 #endif // CFG_TUD_AUDIO_ENABLE_EP_IN && (USE_LINEAR_BUFFER || CFG_TUD_AUDIO_ENABLE_DECODING)
 
 // EP OUT software buffers and mutexes
 #if CFG_TUD_AUDIO_ENABLE_EP_OUT && !CFG_TUD_AUDIO_ENABLE_DECODING
 #if CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_1[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_1[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_out_ff_mutex_rd_1;                                                            // No need for write mutex as only USB driver writes into FIFO
 #endif
 #endif // CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ > 0
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_OUT_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_2[CFG_TUD_AUDIO_FUNC_2_EP_OUT_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_2[CFG_TUD_AUDIO_FUNC_2_EP_OUT_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_out_ff_mutex_rd_2;                                                            // No need for write mutex as only USB driver writes into FIFO
 #endif
 #endif // CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_OUT_SW_BUF_SZ > 0
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_EP_OUT_SW_BUF_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_3[CFG_TUD_AUDIO_FUNC_3_EP_OUT_SW_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t audio_ep_out_sw_buf_3[CFG_TUD_AUDIO_FUNC_3_EP_OUT_SW_BUF_SZ];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t ep_out_ff_mutex_rd_3;                                                            // No need for write mutex as only USB driver writes into FIFO
 #endif
@@ -163,52 +163,52 @@ osal_mutex_def_t ep_out_ff_mutex_rd_3;
 // - the software encoding is used - in this case the linear buffers serve as a target memory where logical channels are encoded into
 #if CFG_TUD_AUDIO_ENABLE_EP_OUT && (USE_LINEAR_BUFFER || CFG_TUD_AUDIO_ENABLE_DECODING)
 #if CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_1[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_1[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX];
 #endif
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_EP_OUT_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_2[CFG_TUD_AUDIO_FUNC_2_EP_OUT_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_2[CFG_TUD_AUDIO_FUNC_2_EP_OUT_SZ_MAX];
 #endif
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_EP_OUT_SZ_MAX > 0
-CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_3[CFG_TUD_AUDIO_FUNC_3_EP_OUT_SZ_MAX];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t lin_buf_out_3[CFG_TUD_AUDIO_FUNC_3_EP_OUT_SZ_MAX];
 #endif
 #endif // CFG_TUD_AUDIO_ENABLE_EP_OUT && (USE_LINEAR_BUFFER || CFG_TUD_AUDIO_ENABLE_DECODING)
 
 // Control buffers
-CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_1[CFG_TUD_AUDIO_FUNC_1_CTRL_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_1[CFG_TUD_AUDIO_FUNC_1_CTRL_BUF_SZ];
 #if CFG_TUD_AUDIO > 1
-CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_2[CFG_TUD_AUDIO_FUNC_2_CTRL_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_2[CFG_TUD_AUDIO_FUNC_2_CTRL_BUF_SZ];
 #endif
 #if CFG_TUD_AUDIO > 2
-CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_3[CFG_TUD_AUDIO_FUNC_3_CTRL_BUF_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t ctrl_buf_3[CFG_TUD_AUDIO_FUNC_3_CTRL_BUF_SZ];
 #endif
 
 // Active alternate setting of interfaces
-CFG_TUSB_MEM_ALIGN uint8_t alt_setting_1[CFG_TUD_AUDIO_FUNC_1_N_AS_INT];
+uint8_t alt_setting_1[CFG_TUD_AUDIO_FUNC_1_N_AS_INT];
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_N_AS_INT > 0
-CFG_TUSB_MEM_ALIGN uint8_t alt_setting_2[CFG_TUD_AUDIO_FUNC_2_N_AS_INT];
+uint8_t alt_setting_2[CFG_TUD_AUDIO_FUNC_2_N_AS_INT];
 #endif
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_N_AS_INT > 0
-CFG_TUSB_MEM_ALIGN uint8_t alt_setting_3[CFG_TUD_AUDIO_FUNC_3_N_AS_INT];
+uint8_t alt_setting_3[CFG_TUD_AUDIO_FUNC_3_N_AS_INT];
 #endif
 
 // Software encoding/decoding support FIFOs
 #if CFG_TUD_AUDIO_ENABLE_EP_IN && CFG_TUD_AUDIO_ENABLE_ENCODING
 #if CFG_TUD_AUDIO_FUNC_1_TX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_1[CFG_TUD_AUDIO_FUNC_1_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_1_TX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_1[CFG_TUD_AUDIO_FUNC_1_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_1_TX_SUPP_SW_FIFO_SZ];
 tu_fifo_t tx_supp_ff_1[CFG_TUD_AUDIO_FUNC_1_N_TX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t tx_supp_ff_mutex_wr_1[CFG_TUD_AUDIO_FUNC_1_N_TX_SUPP_SW_FIFO];                   // No need for read mutex as only USB driver reads from FIFO
 #endif
 #endif
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_TX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_2[CFG_TUD_AUDIO_FUNC_2_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_2_TX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_2[CFG_TUD_AUDIO_FUNC_2_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_2_TX_SUPP_SW_FIFO_SZ];
 tu_fifo_t tx_supp_ff_2[CFG_TUD_AUDIO_FUNC_2_N_TX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t tx_supp_ff_mutex_wr_2[CFG_TUD_AUDIO_FUNC_2_N_TX_SUPP_SW_FIFO];                   // No need for read mutex as only USB driver reads from FIFO
 #endif
 #endif
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_TX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_3[CFG_TUD_AUDIO_FUNC_3_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_3_TX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t tx_supp_ff_buf_3[CFG_TUD_AUDIO_FUNC_3_N_TX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_3_TX_SUPP_SW_FIFO_SZ];
 tu_fifo_t tx_supp_ff_3[CFG_TUD_AUDIO_FUNC_3_N_TX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t tx_supp_ff_mutex_wr_3[CFG_TUD_AUDIO_FUNC_3_N_TX_SUPP_SW_FIFO];                   // No need for read mutex as only USB driver reads from FIFO
@@ -218,21 +218,21 @@ osal_mutex_def_t tx_supp_ff_mutex_wr_3[CFG_TUD_AUDIO_FUNC_3_N_TX_SUPP_SW_FIFO];
 
 #if CFG_TUD_AUDIO_ENABLE_EP_OUT && CFG_TUD_AUDIO_ENABLE_DECODING
 #if CFG_TUD_AUDIO_FUNC_1_RX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_1[CFG_TUD_AUDIO_FUNC_1_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_1_RX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_1[CFG_TUD_AUDIO_FUNC_1_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_1_RX_SUPP_SW_FIFO_SZ];
 tu_fifo_t rx_supp_ff_1[CFG_TUD_AUDIO_FUNC_1_N_RX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t rx_supp_ff_mutex_rd_1[CFG_TUD_AUDIO_FUNC_1_N_RX_SUPP_SW_FIFO];                   // No need for write mutex as only USB driver writes into FIFO
 #endif
 #endif
 #if CFG_TUD_AUDIO > 1 && CFG_TUD_AUDIO_FUNC_2_RX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_2[CFG_TUD_AUDIO_FUNC_2_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_2_RX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_2[CFG_TUD_AUDIO_FUNC_2_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_2_RX_SUPP_SW_FIFO_SZ];
 tu_fifo_t rx_supp_ff_2[CFG_TUD_AUDIO_FUNC_2_N_RX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t rx_supp_ff_mutex_rd_2[CFG_TUD_AUDIO_FUNC_2_N_RX_SUPP_SW_FIFO];                   // No need for write mutex as only USB driver writes into FIFO
 #endif
 #endif
 #if CFG_TUD_AUDIO > 2 && CFG_TUD_AUDIO_FUNC_3_RX_SUPP_SW_FIFO_SZ > 0
-CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_3[CFG_TUD_AUDIO_FUNC_3_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_3_RX_SUPP_SW_FIFO_SZ];
+CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t rx_supp_ff_buf_3[CFG_TUD_AUDIO_FUNC_3_N_RX_SUPP_SW_FIFO][CFG_TUD_AUDIO_FUNC_3_RX_SUPP_SW_FIFO_SZ];
 tu_fifo_t rx_supp_ff_3[CFG_TUD_AUDIO_FUNC_3_N_RX_SUPP_SW_FIFO];
 #if CFG_FIFO_MUTEX
 osal_mutex_def_t rx_supp_ff_mutex_rd_3[CFG_TUD_AUDIO_FUNC_3_N_RX_SUPP_SW_FIFO];                   // No need for write mutex as only USB driver writes into FIFO
@@ -294,7 +294,7 @@ typedef struct
 
   // Audio control interrupt buffer - no FIFO - 6 Bytes according to UAC 2 specification (p. 74)
 #if CFG_TUD_AUDIO_INT_CTR_EPSIZE_IN
-  CFG_TUSB_MEM_ALIGN uint8_t ep_int_ctr_buf[CFG_TUD_AUDIO_INT_CTR_EP_IN_SW_BUFFER_SIZE];
+  CFG_TUSB_MEM_SECTION CFG_TUSB_MEM_ALIGN uint8_t ep_int_ctr_buf[CFG_TUD_AUDIO_INT_CTR_EP_IN_SW_BUFFER_SIZE];
 #endif
 
   // Decoding parameters - parameters are set when alternate AS interface is set by host
@@ -643,7 +643,6 @@ static bool audiod_decode_type_I_pcm(uint8_t rhport, audiod_function_t* audio, u
 
   // Determine amount of samples
   uint8_t const n_ff_used               = audio->n_ff_used_rx;
-  uint16_t const nBytesToCopy           = audio->n_channels_per_ff_rx * audio->n_bytes_per_sampe_rx;
   uint16_t const nBytesPerFFToRead      = n_bytes_received / n_ff_used;
   uint8_t cnt_ff;
 
@@ -662,14 +661,14 @@ static bool audiod_decode_type_I_pcm(uint8_t rhport, audiod_function_t* audio, u
       info.len_lin = tu_min16(nBytesPerFFToRead, info.len_lin);
       src = &audio->lin_buf_out[cnt_ff*audio->n_channels_per_ff_rx * audio->n_bytes_per_sampe_rx];
       dst_end = info.ptr_lin + info.len_lin;
-      src = audiod_interleaved_copy_bytes_fast_decode(nBytesToCopy, info.ptr_lin, dst_end, src, n_ff_used);
+      src = audiod_interleaved_copy_bytes_fast_decode(audio->n_bytes_per_sampe_rx, info.ptr_lin, dst_end, src, n_ff_used);
 
       // Handle wrapped part of FIFO
       info.len_wrap = tu_min16(nBytesPerFFToRead - info.len_lin, info.len_wrap);
       if (info.len_wrap != 0)
       {
         dst_end = info.ptr_wrap + info.len_wrap;
-        audiod_interleaved_copy_bytes_fast_decode(nBytesToCopy, info.ptr_wrap, dst_end, src, n_ff_used);
+        audiod_interleaved_copy_bytes_fast_decode(audio->n_bytes_per_sampe_rx, info.ptr_wrap, dst_end, src, n_ff_used);
       }
       tu_fifo_advance_write_pointer(&audio->rx_supp_ff[cnt_ff], info.len_lin + info.len_wrap);
     }
@@ -994,7 +993,7 @@ static uint16_t audiod_encode_type_I_pcm(uint8_t rhport, audiod_function_t* audi
     {
       info.len_lin = tu_min16(nBytesPerFFToSend, info.len_lin);       // Limit up to desired length
       src_end = (uint8_t *)info.ptr_lin + info.len_lin;
-      dst = audiod_interleaved_copy_bytes_fast_encode(nBytesToCopy, info.ptr_lin, src_end, dst, n_ff_used);
+      dst = audiod_interleaved_copy_bytes_fast_encode(audio->n_bytes_per_sampe_tx, info.ptr_lin, src_end, dst, n_ff_used);
 
       // Limit up to desired length
       info.len_wrap = tu_min16(nBytesPerFFToSend - info.len_lin, info.len_wrap);
@@ -1003,7 +1002,7 @@ static uint16_t audiod_encode_type_I_pcm(uint8_t rhport, audiod_function_t* audi
       if (info.len_wrap != 0)
       {
         src_end = (uint8_t *)info.ptr_wrap + info.len_wrap;
-        audiod_interleaved_copy_bytes_fast_encode(nBytesToCopy, info.ptr_wrap, src_end, dst, n_ff_used);
+        audiod_interleaved_copy_bytes_fast_encode(audio->n_bytes_per_sampe_tx, info.ptr_wrap, src_end, dst, n_ff_used);
       }
 
       tu_fifo_advance_read_pointer(&audio->tx_supp_ff[cnt_ff], info.len_lin + info.len_wrap);
@@ -1481,18 +1480,20 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const *
     audio->ep_in_as_intf_num = 0;
     usbd_edpt_close(rhport, audio->ep_in);
 
-    // Invoke callback - can be used to stop data sampling
-    if (tud_audio_set_itf_close_EP_cb) TU_VERIFY(tud_audio_set_itf_close_EP_cb(rhport, p_request));
-
-    audio->ep_in = 0;                           // Necessary?
-
-    // Clear support FIFOs if used
-#if CFG_TUD_AUDIO_ENABLE_ENCODING
+    // Clear FIFOs, since data is no longer valid
+#if !CFG_TUD_AUDIO_ENABLE_ENCODING
+    tu_fifo_clear(&audio->ep_in_ff);
+#else
     for (uint8_t cnt = 0; cnt < audio->n_tx_supp_ff; cnt++)
     {
       tu_fifo_clear(&audio->tx_supp_ff[cnt]);
     }
 #endif
+    
+    // Invoke callback - can be used to stop data sampling
+    if (tud_audio_set_itf_close_EP_cb) TU_VERIFY(tud_audio_set_itf_close_EP_cb(rhport, p_request));
+
+    audio->ep_in = 0;                           // Necessary?
 
   }
 #endif
@@ -1502,16 +1503,22 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const *
   {
     audio->ep_out_as_intf_num = 0;
     usbd_edpt_close(rhport, audio->ep_out);
-    audio->ep_out = 0;                          // Necessary?
 
-    // Clear support FIFOs if used
-#if CFG_TUD_AUDIO_ENABLE_DECODING
+    // Clear FIFOs, since data is no longer valid
+#if !CFG_TUD_AUDIO_ENABLE_DECODING
+    tu_fifo_clear(&audio->ep_out_ff);
+#else
     for (uint8_t cnt = 0; cnt < audio->n_rx_supp_ff; cnt++)
     {
       tu_fifo_clear(&audio->rx_supp_ff[cnt]);
     }
 #endif
 
+    // Invoke callback - can be used to stop data sampling
+    if (tud_audio_set_itf_close_EP_cb) TU_VERIFY(tud_audio_set_itf_close_EP_cb(rhport, p_request));
+
+    audio->ep_out = 0;                          // Necessary?
+
     // Close corresponding feedback EP
 #if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP
     usbd_edpt_close(rhport, audio->ep_fb);
@@ -1605,9 +1612,17 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const *
             TU_ASSERT( audio->n_ff_used_rx <= audio->n_rx_supp_ff );
 #endif
 #endif
+
+#if CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP
+            // In case of asynchronous EP, call Cb after ep_fb is set
+            if (!(((tusb_desc_endpoint_t const *) p_desc)->bmAttributes.sync == 0x01 && audio->ep_fb == 0))
+            {
+              if (tud_audio_set_itf_cb) TU_VERIFY(tud_audio_set_itf_cb(rhport, p_request));
+            }
+#else
             // Invoke callback
             if (tud_audio_set_itf_cb) TU_VERIFY(tud_audio_set_itf_cb(rhport, p_request));
-
+#endif
             // Prepare for incoming data
 #if USE_LINEAR_BUFFER_RX
             TU_VERIFY(usbd_edpt_xfer(rhport, audio->ep_out, audio->lin_buf_out, audio->ep_out_sz), false);
@@ -1621,8 +1636,11 @@ static bool audiod_set_interface(uint8_t rhport, tusb_control_request_t const *
           {
             audio->ep_fb = ep_addr;
 
-            // Invoke callback
-            if (tud_audio_set_itf_cb) TU_VERIFY(tud_audio_set_itf_cb(rhport, p_request));
+            // Invoke callback after ep_out is set
+            if (audio->ep_out != 0)
+            {
+              if (tud_audio_set_itf_cb) TU_VERIFY(tud_audio_set_itf_cb(rhport, p_request));
+            }
           }
 #endif
 #endif // CFG_TUD_AUDIO_ENABLE_EP_OUT
@@ -1916,8 +1934,12 @@ bool audiod_xfer_cb(uint8_t rhport, uint8_t ep_addr, xfer_result_t result, uint3
     {
       if (tud_audio_fb_done_cb) TU_VERIFY(tud_audio_fb_done_cb(rhport));
 
-      // Schedule next transmission - value is changed bytud_audio_n_fb_set() in the meantime or the old value gets sent
-      return audiod_fb_send(rhport, &_audiod_fct[func_id]);
+      // Schedule a transmit with the new value if EP is not busy 
+      if (!usbd_edpt_busy(rhport, _audiod_fct[func_id].ep_fb))
+      {
+        // Schedule next transmission - value is changed bytud_audio_n_fb_set() in the meantime or the old value gets sent
+        return audiod_fb_send(rhport, &_audiod_fct[func_id]);
+      }
     }
 #endif
 #endif
@@ -1997,15 +2019,17 @@ static bool audiod_get_AS_interface_index(uint8_t itf, audiod_function_t * audio
     while (p_desc < p_desc_end)
     {
       // We assume the number of alternate settings is increasing thus we return the index of alternate setting zero!
-      if (tu_desc_type(p_desc) == TUSB_DESC_INTERFACE && ((tusb_desc_interface_t const * )p_desc)->bInterfaceNumber == itf)
+      if (tu_desc_type(p_desc) == TUSB_DESC_INTERFACE && ((tusb_desc_interface_t const * )p_desc)->bAlternateSetting == 0)
       {
-        *idxItf = tmp;
-        *pp_desc_int = p_desc;
-        return true;
+        if (((tusb_desc_interface_t const * )p_desc)->bInterfaceNumber == itf)
+        {
+          *idxItf = tmp;
+          *pp_desc_int = p_desc;
+          return true;
+        }
+        // Increase index, bytes read, and pointer
+        tmp++;
       }
-
-      // Increase index, bytes read, and pointer
-      tmp++;
       p_desc = tu_desc_next(p_desc);
     }
   }
@@ -2207,22 +2231,19 @@ bool tud_audio_n_fb_set(uint8_t func_id, uint32_t feedback)
   TU_VERIFY(func_id < CFG_TUD_AUDIO && _audiod_fct[func_id].p_desc != NULL);
 
   // Format the feedback value
-  if (_audiod_fct[func_id].rhport == 0)
-  {
-    uint8_t * fb = (uint8_t *) &_audiod_fct[func_id].fb_val;
-
-    // For FS format is 10.14
-    *(fb++) = (feedback >> 2) & 0xFF;
-    *(fb++) = (feedback >> 10) & 0xFF;
-    *(fb++) = (feedback >> 18) & 0xFF;
-    // 4th byte is needed to work correctly with MS Windows
-    *fb = 0;
-  }
-  else
-  {
-    // For HS format is 16.16 as originally demanded
-    _audiod_fct[func_id].fb_val = feedback;
-  }
+#if !TUD_OPT_HIGH_SPEED
+  uint8_t * fb = (uint8_t *) &_audiod_fct[func_id].fb_val;
+
+  // For FS format is 10.14
+  *(fb++) = (feedback >> 2) & 0xFF;
+  *(fb++) = (feedback >> 10) & 0xFF;
+  *(fb++) = (feedback >> 18) & 0xFF;
+  // 4th byte is needed to work correctly with MS Windows
+  *fb = 0;
+#else
+  // For HS format is 16.16 as originally demanded
+  _audiod_fct[func_id].fb_val = feedback;
+#endif
 
   // Schedule a transmit with the new value if EP is not busy - this triggers repetitive scheduling of the feedback value
   if (!usbd_edpt_busy(_audiod_fct[func_id].rhport, _audiod_fct[func_id].ep_fb))

src/device/usbd.h

@@ -542,6 +542,11 @@ TU_ATTR_WEAK bool tud_vendor_control_xfer_cb(uint8_t rhport, uint8_t stage, tusb
   /* Standard AS Isochronous Feedback Endpoint Descriptor(4.10.2.1) */\
   TUD_AUDIO_DESC_STD_AS_ISO_FB_EP(/*_ep*/ _epfb, /*_interval*/ 1)\
 
+//   Calculate wMaxPacketSize of Endpoints
+#define TUD_AUDIO_EP_SIZE(_maxFrequency, _nBytesPerSample, _nChannels) \
+    ((((_maxFrequency + ((CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 7999 : 999)) / ((CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 8000 : 1000)) + 1) * _nBytesPerSample * _nChannels)
+
+
 //------------- TUD_USBTMC/USB488 -------------//
 #define TUD_USBTMC_APP_CLASS    (TUSB_CLASS_APPLICATION_SPECIFIC)
 #define TUD_USBTMC_APP_SUBCLASS 0x03u