apps: Merge auracast and auracast_usb applications

This adds new AUDIO_USB syscfg option to disable the USB audio support
in auracast_usb application.
This fixes code duplication, so that auracast_usb has been renamed
to auracast, where previous auracast application has been removed.

apps/auracast/pkg.yml

@@ -32,8 +32,17 @@ pkg.deps:
     - nimble/host/store/config
     - nimble/host/audio/services/auracast
     - "@apache-mynewt-core/kernel/os"
+    - "@apache-mynewt-core/sys/config"
     - "@apache-mynewt-core/sys/console"
     - "@apache-mynewt-core/sys/log"
     - "@apache-mynewt-core/sys/stats"
     - "@apache-mynewt-core/sys/sysinit"
     - "@apache-mynewt-core/sys/id"
+
+pkg.deps.AUDIO_USB:
+    - ext/liblc3
+    - ext/libsamplerate
+    - "@apache-mynewt-core/hw/usb/tinyusb"
+
+pkg.init:
+    audio_init: 402

apps/auracast_usb/src/app_priv.h → apps/auracast/src/app_priv.h

@@ -21,6 +21,7 @@
 #define H_APP_PRIV_
 
 #include <syscfg/syscfg.h>
+#include <stdint.h>
 
 #ifndef MIN
 #define MIN(a,b) ((a) < (b) ? (a) : (b))
@@ -40,10 +41,5 @@
 #define LC3_FPDT                (AUDIO_PCM_SAMPLE_RATE * LC3_FRAME_DURATION / 1000000)
 #define BIG_NUM_BIS             (MIN(AUDIO_CHANNELS, MYNEWT_VAL(BIG_NUM_BIS)))
 
-struct chan {
-    void *encoder;
-    uint16_t handle;
-};
-
-extern struct chan chans[AUDIO_CHANNELS];
+void audio_chan_set_conn_handle(uint8_t chan_idx, uint16_t conn_handle);
 #endif /* H_APP_PRIV_ */

apps/auracast_usb/src/audio_usb.c → apps/auracast/src/audio.c

@@ -18,13 +18,26 @@
  */
 
 #include <assert.h>
+#include <os/os.h>
+#include <stdint.h>
 #include <string.h>
 #include <syscfg/syscfg.h>
-#include <os/os.h>
+
+#include "console/console.h"
+#include "host/ble_hs.h"
+#include "host/ble_iso.h"
+
+#include "app_priv.h"
+
+struct chan {
+    void *encoder;
+    uint16_t handle;
+} chans[AUDIO_CHANNELS];
+
+#if MYNEWT_VAL(AUDIO_USB)
 #include <common/tusb_fifo.h>
 #include <class/audio/audio_device.h>
 #include <usb_audio.h>
-#include "console/console.h"
 
 #include <lc3.h>
 #include <samplerate.h>
@@ -33,16 +46,12 @@
 #include "host/ble_gap.h"
 #include "os/os_cputime.h"
 
-#include "app_priv.h"
-
 #define AUDIO_BUF_SIZE      1024
 
 static uint8_t g_usb_enabled;
 
 static void usb_data_func(struct os_event *ev);
 
-struct chan chans[AUDIO_CHANNELS];
-
 static struct os_event usb_data_ev = {
     .ev_cb = usb_data_func,
 };
@@ -239,7 +248,7 @@ tud_audio_rx_done_post_read_cb(uint8_t rhport, uint16_t n_bytes_received,
     return true;
 }
 
-void
+static void
 audio_usb_init(void)
 {
     /* Need to reference those explicitly, so they are always pulled by linker
@@ -280,3 +289,90 @@ audio_usb_init(void)
     resampler_ratio = resampler_out_rate / resampler_in_rate;
 #endif
 }
+#else
+#include "audio_data.h"
+
+#define BROADCAST_MAX_SDU 120
+
+static int audio_data_offset;
+static struct os_callout audio_broadcast_callout;
+
+static void
+audio_broadcast_event_cb(struct os_event *ev)
+{
+    assert(ev != NULL);
+    uint32_t ev_start_time = os_cputime_ticks_to_usecs(os_cputime_get32());
+
+#if MYNEWT_VAL(AURACAST_CHAN_NUM) > 1
+    if (audio_data_offset + BROADCAST_MAX_SDU >= sizeof(audio_data)) {
+        audio_data_offset = 0;
+    }
+
+    if (chans[0].handle != BLE_HS_CONN_HANDLE_NONE) {
+        ble_iso_tx(chans[0].handle, (void *) (audio_data + audio_data_offset),
+                   BROADCAST_MAX_SDU);
+    }
+    if (chans[1].handle != BLE_HS_CONN_HANDLE_NONE) {
+        ble_iso_tx(chans[1].handle, (void *) (audio_data + audio_data_offset),
+                   BROADCAST_MAX_SDU);
+    }
+#else
+    if (audio_data_offset + 2 * BROADCAST_MAX_SDU >= sizeof(audio_data)) {
+        audio_data_offset = 0;
+    }
+
+    uint8_t lr_payload[BROADCAST_MAX_SDU * 2];
+    memcpy(lr_payload, audio_data + audio_data_offset, BROADCAST_MAX_SDU);
+    memcpy(lr_payload + BROADCAST_MAX_SDU, audio_data + audio_data_offset,
+           BROADCAST_MAX_SDU);
+
+    if (chans[0].handle != BLE_HS_CONN_HANDLE_NONE) {
+        ble_iso_tx(chans[0].handle, (void *) (lr_payload),
+                   BROADCAST_MAX_SDU * 2);
+    }
+#endif
+    audio_data_offset += BROADCAST_MAX_SDU;
+
+    /** Use cputime to time LC3_FRAME_DURATION, as these ticks are more
+     *  accurate than os_time ones. This assures that we do not push
+     *  LC3 data to ISO before interval, which could lead to
+     *  controller running out of buffers. This is only needed because
+     *  we already have coded data in an array - in real world application
+     *  we usually wait for new audio to arrive, and lose time to code it too.
+     */
+    while (os_cputime_ticks_to_usecs(os_cputime_get32()) - ev_start_time <
+           (MYNEWT_VAL(LC3_FRAME_DURATION)));
+
+    os_callout_reset(&audio_broadcast_callout, 0);
+}
+
+static void
+audio_dummy_init(void)
+{
+    os_callout_init(&audio_broadcast_callout, os_eventq_dflt_get(),
+                    audio_broadcast_event_cb, NULL);
+
+    os_callout_reset(&audio_broadcast_callout, 0);
+}
+#endif /* AUDIO_USB */
+
+void
+audio_init(void)
+{
+    for (size_t i = 0; i < ARRAY_SIZE(chans); i++) {
+        chans[i].handle = BLE_HS_CONN_HANDLE_NONE;
+    }
+
+#if MYNEWT_VAL(AUDIO_USB)
+    audio_usb_init();
+#else
+    audio_dummy_init();
+#endif /* AUDIO_USB */
+}
+
+void
+audio_chan_set_conn_handle(uint8_t chan_idx, uint16_t conn_handle)
+{
+    assert(chan_idx < ARRAY_SIZE(chans));
+    chans[chan_idx].handle = conn_handle;
+}