Add an optional HID debug interface.

examples/device/uac2_speaker_fb/src/audio_debug.py

@@ -0,0 +1,62 @@
+# Install python3 HID package https://pypi.org/project/hid/
+import hid
+from ctypes import *
+import matplotlib.pyplot as plt
+import matplotlib.animation as animation
+
+# Example must be compiled with CFG_AUDIO_DEBUG=1
+VID = 0xcafe
+PID = 0x4014
+
+CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX = 2
+
+class audio_debug_info_t (Structure):
+    _fields_ = [("sample_rate", c_uint32),
+                ("alt_settings", c_uint8),
+                ("mute", (CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX + 1) * c_int8),
+                ("volume", (CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX + 1) * c_int16),
+                ("fifo_size", c_uint16),
+                ("fifo_count", c_uint16),
+                ("fifo_count_avg", c_uint16)
+                ]
+
+dev = hid.Device(VID, PID)
+
+if dev:
+    # Create figure for plotting
+    fig = plt.figure()
+    ax = fig.add_subplot(1, 1, 1)
+    fifo_avg = []
+    fifo_cnt = []
+    # This function is called periodically from FuncAnimation
+    def animate(i):
+
+        for i in range(100):
+            str_in = dev.read(64, 10)
+            if str_in:
+                info = audio_debug_info_t.from_buffer_copy(str_in)
+
+                global fifo_avg
+                global fifo_cnt
+                fifo_avg.append(info.fifo_count_avg)
+                fifo_cnt.append(info.fifo_count)
+
+        # Limit to 1000 items
+        fifo_avg = fifo_avg[-1000:]
+        fifo_cnt = fifo_cnt[-1000:]
+
+        # Draw x and y lists
+        ax.clear()
+        ax.plot(fifo_cnt, label='FIFO count')
+        ax.plot(fifo_avg, label='FIFO average')
+        ax.legend()
+        ax.set_ylim(bottom=0, top=info.fifo_size)
+
+        # Format plot
+        plt.title('FIFO information')
+        plt.grid()
+
+        print(f'Sample rate:{info.sample_rate} | Alt settings:{info.alt_settings} | Volume:{info.volume[:]}')
+
+    ani = animation.FuncAnimation(fig, animate, interval=100)
+    plt.show()

examples/device/uac2_speaker_fb/src/common_types.h

@@ -0,0 +1,52 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2023 HiFiPhile
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#ifndef _COMMON_TYPES_H_
+#define _COMMON_TYPES_H_
+
+enum
+{
+  ITF_NUM_AUDIO_CONTROL = 0,
+  ITF_NUM_AUDIO_STREAMING,
+#if CFG_AUDIO_DEBUG
+  ITF_NUM_DEBUG,
+#endif
+  ITF_NUM_TOTAL
+};
+
+#if CFG_AUDIO_DEBUG
+typedef struct
+  {
+    uint32_t sample_rate;
+    uint8_t alt_settings;
+    int8_t mute[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX + 1];
+    int16_t volume[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX + 1];
+    uint16_t fifo_size;
+    uint16_t fifo_count;
+    uint16_t fifo_count_avg;
+  } audio_debug_info_t;
+#endif
+
+#endif

examples/device/uac2_speaker_fb/src/main.c

@@ -29,6 +29,7 @@
 #include "bsp/board_api.h"
 #include "tusb.h"
 #include "usb_descriptors.h"
+#include "common_types.h"
 
 //--------------------------------------------------------------------+
 // MACRO CONSTANT TYPEDEF PROTOTYPES
@@ -88,6 +89,11 @@ uint16_t i2s_dummy_buffer[CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ/2];
 void led_blinking_task(void);
 void audio_task(void);
 
+#if CFG_AUDIO_DEBUG
+void audio_debug_task(void);
+uint8_t current_alt_settings;
+#endif
+
 /*------------- MAIN -------------*/
 int main(void)
 {
@@ -107,6 +113,9 @@ int main(void)
     tud_task(); // TinyUSB device task
     audio_task();
     led_blinking_task();
+#if CFG_AUDIO_DEBUG
+    audio_debug_task();
+#endif
   }
 }
 
@@ -141,6 +150,10 @@ void tud_resume_cb(void)
   blink_interval_ms = tud_mounted() ? BLINK_MOUNTED : BLINK_NOT_MOUNTED;
 }
 
+//--------------------------------------------------------------------+
+// Application Callback API Implementations
+//--------------------------------------------------------------------+
+
 // Helper for clock get requests
 static bool tud_audio_clock_get_request(uint8_t rhport, audio_control_request_t const *request)
 {
@@ -283,10 +296,6 @@ static bool tud_audio_feature_unit_set_request(uint8_t rhport, audio_control_req
   }
 }
 
-//--------------------------------------------------------------------+
-// Application Callback API Implementations
-//--------------------------------------------------------------------+
-
 // Invoked when audio class specific get request received for an entity
 bool tud_audio_get_req_entity_cb(uint8_t rhport, tusb_control_request_t const *p_request)
 {
@@ -342,6 +351,10 @@ bool tud_audio_set_itf_cb(uint8_t rhport, tusb_control_request_t const * p_reque
   if (ITF_NUM_AUDIO_STREAMING == itf && alt != 0)
       blink_interval_ms = BLINK_STREAMING;
 
+#if CFG_AUDIO_DEBUG
+  current_alt_settings = alt;
+#endif
+
   return true;
 }
 
@@ -353,14 +366,15 @@ void tud_audio_feedback_params_cb(uint8_t func_id, uint8_t alt_itf, audio_feedba
   feedback_param->method = AUDIO_FEEDBACK_METHOD_FIFO_COUNT;
   feedback_param->sample_freq = current_sample_rate;
 }
+
 //--------------------------------------------------------------------+
 // AUDIO Task
 //--------------------------------------------------------------------+
 
 void audio_task(void)
 {
-  // Yet to be filled - e.g. write audio to I2S buffer.
-  // Here we simulate a I2S transmit callback every 1ms.
+  // Replace audio_task() with your I2S transmit callback.
+  // Here we simulate a callback called every 1ms.
   static uint32_t start_ms = 0;
   uint32_t curr_ms = board_millis();
   if ( start_ms == curr_ms ) return; // not enough time
@@ -399,3 +413,65 @@ void led_blinking_task(void)
   board_led_write(led_state);
   led_state = 1 - led_state;
 }
+
+#if CFG_AUDIO_DEBUG
+//--------------------------------------------------------------------+
+// HID interface for audio debug
+//--------------------------------------------------------------------+
+
+// Every 1ms, we will sent 1 debug information report
+void audio_debug_task(void)
+{
+  static uint32_t start_ms = 0;
+  uint32_t curr_ms = board_millis();
+  if ( start_ms == curr_ms ) return; // not enough time
+  start_ms = curr_ms;
+
+  uint16_t fifo_count = tud_audio_available();
+  static uint32_t fifo_count_avg;
+
+  // Same averaging method used in UAC2 class
+  fifo_count_avg = (uint32_t)(((uint64_t)fifo_count_avg * 63  + ((uint32_t)fifo_count << 16)) >> 6);
+
+  audio_debug_info_t debug_info;
+  debug_info.sample_rate    = current_sample_rate;
+  debug_info.alt_settings   = current_alt_settings;
+  debug_info.fifo_size      = CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ;
+  debug_info.fifo_count     = fifo_count;
+  debug_info.fifo_count_avg = fifo_count_avg >> 16;
+  for (int i = 0; i < CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_RX + 1; i++)
+  {
+    debug_info.mute[i] = mute[i];
+    debug_info.volume[i] = volume[i];
+  }
+
+  tud_hid_report(0, &debug_info, sizeof(debug_info));
+}
+
+// Invoked when received GET_REPORT control request
+// Unused here
+uint16_t tud_hid_get_report_cb(uint8_t itf, uint8_t report_id, hid_report_type_t report_type, uint8_t* buffer, uint16_t reqlen)
+{
+  // TODO not Implemented
+  (void) itf;
+  (void) report_id;
+  (void) report_type;
+  (void) buffer;
+  (void) reqlen;
+
+  return 0;
+}
+
+// Invoked when received SET_REPORT control request or
+// Unused here
+void tud_hid_set_report_cb(uint8_t itf, uint8_t report_id, hid_report_type_t report_type, uint8_t const* buffer, uint16_t bufsize)
+{
+  // This example doesn't use multiple report and report ID
+  (void) itf;
+  (void) report_id;
+  (void) report_type;
+  (void) buffer;
+  (void) bufsize;
+}
+
+#endif

examples/device/uac2_speaker_fb/src/tusb_config.h

@@ -32,6 +32,7 @@ extern "C" {
 #endif
 
 #include "usb_descriptors.h"
+
 //--------------------------------------------------------------------+
 // Board Specific Configuration
 //--------------------------------------------------------------------+
@@ -59,6 +60,8 @@ extern "C" {
 #define CFG_TUSB_OS           OPT_OS_NONE
 #endif
 
+// It's recommanded to disable debug unless for control requests debugging,
+// as the extra time needed will impact data stream !
 #ifndef CFG_TUSB_DEBUG
 #define CFG_TUSB_DEBUG        0
 #endif
@@ -88,16 +91,29 @@ extern "C" {
 // DEVICE CONFIGURATION
 //--------------------------------------------------------------------
 
+// Expose audio class debug information via HID interface
+#ifndef CFG_AUDIO_DEBUG
+#define CFG_AUDIO_DEBUG           1
+#endif
+
 #ifndef CFG_TUD_ENDPOINT0_SIZE
 #define CFG_TUD_ENDPOINT0_SIZE    64
 #endif
 
+#define CFG_TUD_HID_EP_BUFSIZE    64
+
 //------------- CLASS -------------//
+#define CFG_TUD_AUDIO             1
+
+#if CFG_AUDIO_DEBUG
+#define CFG_TUD_HID               1
+#else
+#define CFG_TUD_HID               0
+#endif
+
 #define CFG_TUD_CDC               0
 #define CFG_TUD_MSC               0
-#define CFG_TUD_HID               0
 #define CFG_TUD_MIDI              0
-#define CFG_TUD_AUDIO             1
 #define CFG_TUD_VENDOR            0
 
 //--------------------------------------------------------------------
@@ -126,13 +142,13 @@ extern "C" {
 #define CFG_TUD_AUDIO_FUNC_1_EP_OUT_SW_BUF_SZ     (TUD_OPT_HIGH_SPEED ? 32 : 4) * CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX // Example read FIFO every 1ms, so it should be 8 times larger for HS device
 
 // Enable feedback EP
-#define CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP                            1
+#define CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP                             1
 
 // 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 	                             1
 
 // Size of control request buffer
-#define CFG_TUD_AUDIO_FUNC_1_CTRL_BUF_SZ	                        64
+#define CFG_TUD_AUDIO_FUNC_1_CTRL_BUF_SZ	                         64
 
 #ifdef __cplusplus
 }