Generalize audio driver for 3 audio functions plus a lot more.

- Audio format and parameters are parsed from descriptors thus user no
longer needs to give them explicitely

- Tested for 4 channel software type I PCM encoding with 16 bit with 1
channel per FIFO and 2 channels per FIFO (this is I2S specific)

3 files changed, 23 insertions, 18 deletions

diff --git a/examples/device/audio_test/src/main.c b/examples/device/audio_test/src/main.c
index a631f37b6..7cbf57946 100644
--- a/examples/device/audio_test/src/main.c
+++ b/examples/device/audio_test/src/main.c
@@ -53,17 +53,17 @@ static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
 
 // Audio controls
 // Current states
-bool mute[CFG_TUD_AUDIO_N_CHANNELS_TX + 1]; 						// +1 for master channel 0
-uint16_t volume[CFG_TUD_AUDIO_N_CHANNELS_TX + 1]; 					// +1 for master channel 0
+bool mute[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX + 1]; 						// +1 for master channel 0
+uint16_t volume[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX + 1]; 					// +1 for master channel 0
 uint32_t sampFreq;
 uint8_t clkValid;
 
 // Range states
-audio_control_range_2_n_t(1) volumeRng[CFG_TUD_AUDIO_N_CHANNELS_TX+1]; 			// Volume range state
+audio_control_range_2_n_t(1) volumeRng[CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX+1]; 			// Volume range state
 audio_control_range_4_n_t(1) sampleFreqRng; 						// Sample frequency range state
 
 // Audio test data
-uint16_t test_buffer_audio[CFG_TUD_AUDIO_EPSIZE_IN/2];
+uint16_t test_buffer_audio[CFG_TUD_AUDIO_EP_SZ_IN/2];
 uint16_t startVal = 0;
 
 void led_blinking_task(void);
diff --git a/examples/device/audio_test/src/tusb_config.h b/examples/device/audio_test/src/tusb_config.h
index 557a8b15e..d3b617319 100644
--- a/examples/device/audio_test/src/tusb_config.h
+++ b/examples/device/audio_test/src/tusb_config.h
@@ -91,6 +91,21 @@ extern "C" {
 // AUDIO CLASS DRIVER CONFIGURATION
 //--------------------------------------------------------------------
 
+// Have a look into audio_device.h for all configurations
+
+#define CFG_TUD_AUDIO_FUNC_1_DESC_LEN                                 TUD_AUDIO_MIC_ONE_CH_DESC_LEN
+#define CFG_TUD_AUDIO_FUNC_1_N_AS_INT                                 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_CTRL_BUF_SZ                              64                                      // Size of control request buffer
+
+#define CFG_TUD_AUDIO_ENABLE_EP_IN                                    1
+#define CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX                    2                                       // Driver gets this info from the descriptors - we define it here to use it to setup the descriptors and to do calculations with it below
+#define CFG_TUD_AUDIO_FUNC_1_N_CHANNELS_TX                            1                                       // Driver gets this info from the descriptors - we define it here to use it to setup the descriptors and to do calculations with it below - be aware: for different number of channels you need another descriptor!
+#define CFG_TUD_AUDIO_EP_SZ_IN                                        48 * 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 1 Channel
+#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX                             CFG_TUD_AUDIO_EP_SZ_IN
+#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ                          CFG_TUD_AUDIO_EP_SZ_IN + 1
+
+
+
 // Audio format type
 #define CFG_TUD_AUDIO_FORMAT_TYPE_TX 				AUDIO_FORMAT_TYPE_I
 
@@ -100,14 +115,11 @@ extern "C" {
 #define CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX			2
 
 // 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_EPSIZE_IN                                       48 * CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX * CFG_TUD_AUDIO_N_CHANNELS_TX                              // ceil(f_s/1000) * CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX * CFG_TUD_AUDIO_N_CHANNELS_TX
-#define CFG_TUD_AUDIO_EP_IN_SW_BUFFER_SIZE 			CFG_TUD_AUDIO_EPSIZE_IN + CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX * CFG_TUD_AUDIO_N_CHANNELS_TX 	// Just for safety one sample more space
+#define CFG_TUD_AUDIO_FUNC_1_EP_IN_SW_BUF_SZ                          CFG_TUD_AUDIO_EPSIZE_IN + CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX * CFG_TUD_AUDIO_N_CHANNELS_TX         // Just for safety one sample more space
 
-// 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_N_AS_INT 			          1
 
-// Size of control request buffer
-#define CFG_TUD_AUDIO_CTRL_BUF_SIZE 				64
 
 #ifdef __cplusplus
 }
diff --git a/examples/device/audio_test/src/usb_descriptors.c b/examples/device/audio_test/src/usb_descriptors.c
index d4869a940..67dd34d2a 100644
--- a/examples/device/audio_test/src/usb_descriptors.c
+++ b/examples/device/audio_test/src/usb_descriptors.c
@@ -79,7 +79,7 @@ enum
   ITF_NUM_TOTAL
 };
 
-#define CONFIG_TOTAL_LEN    	(TUD_CONFIG_DESC_LEN + CFG_TUD_AUDIO * TUD_AUDIO_MIC_DESC_LEN)
+#define CONFIG_TOTAL_LEN    	(TUD_CONFIG_DESC_LEN + CFG_TUD_AUDIO * TUD_AUDIO_MIC_ONE_CH_DESC_LEN)
 
 #if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
 // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
@@ -89,20 +89,13 @@ enum
 #define EPNUM_AUDIO   0x01
 #endif
 
-// These variables are required by the audio driver in audio_device.c
-
-// List of audio descriptor lengths which is required by audio driver - you need as many entries as CFG_TUD_AUDIO - unfortunately this is not possible to determine otherwise
-const uint16_t tud_audio_desc_lengths[] = {TUD_AUDIO_MIC_DESC_LEN};
-
-// TAKE CARE - THE NUMBER OF AUDIO STREAMING INTERFACES PER AUDIO FUNCTION MUST NOT EXCEED CFG_TUD_AUDIO_N_AS_INT - IF IT DOES INCREASE CFG_TUD_AUDIO_N_AS_INT IN tusb_config.h!
-
 uint8_t const desc_configuration[] =
 {
     // Interface count, string index, total length, attribute, power in mA
     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_MIC_DESCRIPTOR(/*_itfnum*/ ITF_NUM_AUDIO_CONTROL, /*_stridx*/ 0, /*_nBytesPerSample*/ CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX, /*_nBitsUsedPerSample*/ 16, /*_epin*/ 0x80 | EPNUM_AUDIO, /*_epsize*/ CFG_TUD_AUDIO_EPSIZE_IN)
+    TUD_AUDIO_MIC_ONE_CH_DESCRIPTOR(/*_itfnum*/ ITF_NUM_AUDIO_CONTROL, /*_stridx*/ 0, /*_nBytesPerSample*/ CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX, /*_nBitsUsedPerSample*/ CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE_TX*8, /*_epin*/ 0x80 | EPNUM_AUDIO, /*_epsize*/ CFG_TUD_AUDIO_EP_SZ_IN)
 };
 
 // Invoked when received GET CONFIGURATION DESCRIPTOR