1 /*
2  * Copyright 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #define LOG_TAG "a2dp_vendor_aptx_encoder"
18 
19 #include "a2dp_vendor_aptx_encoder.h"
20 
21 #include <dlfcn.h>
22 #include <inttypes.h>
23 #include <stdio.h>
24 #include <string.h>
25 
26 #include "a2dp_vendor.h"
27 #include "a2dp_vendor_aptx.h"
28 #include "bt_common.h"
29 #include "osi/include/log.h"
30 #include "osi/include/osi.h"
31 
32 //
33 // Encoder for aptX Source Codec
34 //
35 
36 //
37 // The aptX encoder shared library, and the functions to use
38 //
39 static const char* APTX_ENCODER_LIB_NAME = "libaptX_encoder.so";
40 static void* aptx_encoder_lib_handle = NULL;
41 
42 static const char* APTX_ENCODER_INIT_NAME = "aptxbtenc_init";
43 typedef int (*tAPTX_ENCODER_INIT)(void* state, short endian);
44 
45 static const char* APTX_ENCODER_ENCODE_STEREO_NAME = "aptxbtenc_encodestereo";
46 typedef int (*tAPTX_ENCODER_ENCODE_STEREO)(void* state, void* pcmL, void* pcmR,
47                                            void* buffer);
48 
49 static const char* APTX_ENCODER_SIZEOF_PARAMS_NAME = "SizeofAptxbtenc";
50 typedef int (*tAPTX_ENCODER_SIZEOF_PARAMS)(void);
51 
52 static tAPTX_ENCODER_INIT aptx_encoder_init_func;
53 static tAPTX_ENCODER_ENCODE_STEREO aptx_encoder_encode_stereo_func;
54 static tAPTX_ENCODER_SIZEOF_PARAMS aptx_encoder_sizeof_params_func;
55 
56 // offset
57 #if (BTA_AV_CO_CP_SCMS_T == TRUE)
58 #define A2DP_APTX_OFFSET (AVDT_MEDIA_OFFSET + 1)
59 #else
60 // no RTP header for aptX classic
61 #define A2DP_APTX_OFFSET (AVDT_MEDIA_OFFSET - AVDT_MEDIA_HDR_SIZE)
62 #endif
63 
64 #define A2DP_APTX_MAX_PCM_BYTES_PER_READ 4096
65 
66 typedef struct {
67   uint64_t sleep_time_ns;
68   uint32_t pcm_reads;
69   uint32_t pcm_bytes_per_read;
70   uint32_t aptx_bytes;
71   uint32_t frame_size_counter;
72 } tAPTX_FRAMING_PARAMS;
73 
74 typedef struct {
75   uint64_t session_start_us;
76 
77   size_t media_read_total_expected_packets;
78   size_t media_read_total_expected_reads_count;
79   size_t media_read_total_expected_read_bytes;
80 
81   size_t media_read_total_dropped_packets;
82   size_t media_read_total_actual_reads_count;
83   size_t media_read_total_actual_read_bytes;
84 } a2dp_aptx_encoder_stats_t;
85 
86 typedef struct {
87   a2dp_source_read_callback_t read_callback;
88   a2dp_source_enqueue_callback_t enqueue_callback;
89 
90   bool use_SCMS_T;
91   bool is_peer_edr;          // True if the peer device supports EDR
92   bool peer_supports_3mbps;  // True if the peer device supports 3Mbps EDR
93   uint16_t peer_mtu;         // MTU of the A2DP peer
94   uint32_t timestamp;        // Timestamp for the A2DP frames
95 
96   tA2DP_FEEDING_PARAMS feeding_params;
97   tAPTX_FRAMING_PARAMS framing_params;
98   void* aptx_encoder_state;
99   a2dp_aptx_encoder_stats_t stats;
100 } tA2DP_APTX_ENCODER_CB;
101 
102 static tA2DP_APTX_ENCODER_CB a2dp_aptx_encoder_cb;
103 
104 static void a2dp_vendor_aptx_encoder_update(uint16_t peer_mtu,
105                                             A2dpCodecConfig* a2dp_codec_config,
106                                             bool* p_restart_input,
107                                             bool* p_restart_output,
108                                             bool* p_config_updated);
109 static void aptx_init_framing_params(tAPTX_FRAMING_PARAMS* framing_params);
110 static void aptx_update_framing_params(tAPTX_FRAMING_PARAMS* framing_params);
111 static size_t aptx_encode_16bit(tAPTX_FRAMING_PARAMS* framing_params,
112                                 size_t* data_out_index, uint16_t* data16_in,
113                                 uint8_t* data_out);
114 
A2DP_VendorLoadEncoderAptx(void)115 bool A2DP_VendorLoadEncoderAptx(void) {
116   if (aptx_encoder_lib_handle != NULL) return true;  // Already loaded
117 
118   // Open the encoder library
119   aptx_encoder_lib_handle = dlopen(APTX_ENCODER_LIB_NAME, RTLD_NOW);
120   if (aptx_encoder_lib_handle == NULL) {
121     LOG_ERROR(LOG_TAG, "%s: cannot open aptX encoder library %s: %s", __func__,
122               APTX_ENCODER_LIB_NAME, dlerror());
123     return false;
124   }
125 
126   aptx_encoder_init_func = (tAPTX_ENCODER_INIT)dlsym(aptx_encoder_lib_handle,
127                                                      APTX_ENCODER_INIT_NAME);
128   if (aptx_encoder_init_func == NULL) {
129     LOG_ERROR(LOG_TAG,
130               "%s: cannot find function '%s' in the encoder library: %s",
131               __func__, APTX_ENCODER_INIT_NAME, dlerror());
132     A2DP_VendorUnloadEncoderAptx();
133     return false;
134   }
135 
136   aptx_encoder_encode_stereo_func = (tAPTX_ENCODER_ENCODE_STEREO)dlsym(
137       aptx_encoder_lib_handle, APTX_ENCODER_ENCODE_STEREO_NAME);
138   if (aptx_encoder_encode_stereo_func == NULL) {
139     LOG_ERROR(LOG_TAG,
140               "%s: cannot find function '%s' in the encoder library: %s",
141               __func__, APTX_ENCODER_ENCODE_STEREO_NAME, dlerror());
142     A2DP_VendorUnloadEncoderAptx();
143     return false;
144   }
145 
146   aptx_encoder_sizeof_params_func = (tAPTX_ENCODER_SIZEOF_PARAMS)dlsym(
147       aptx_encoder_lib_handle, APTX_ENCODER_SIZEOF_PARAMS_NAME);
148   if (aptx_encoder_sizeof_params_func == NULL) {
149     LOG_ERROR(LOG_TAG,
150               "%s: cannot find function '%s' in the encoder library: %s",
151               __func__, APTX_ENCODER_SIZEOF_PARAMS_NAME, dlerror());
152     A2DP_VendorUnloadEncoderAptx();
153     return false;
154   }
155 
156   return true;
157 }
158 
A2DP_VendorUnloadEncoderAptx(void)159 void A2DP_VendorUnloadEncoderAptx(void) {
160   aptx_encoder_init_func = NULL;
161   aptx_encoder_encode_stereo_func = NULL;
162   aptx_encoder_sizeof_params_func = NULL;
163 
164   if (aptx_encoder_lib_handle != NULL) {
165     dlclose(aptx_encoder_lib_handle);
166     aptx_encoder_lib_handle = NULL;
167   }
168 }
169 
a2dp_vendor_aptx_encoder_init(const tA2DP_ENCODER_INIT_PEER_PARAMS * p_peer_params,A2dpCodecConfig * a2dp_codec_config,a2dp_source_read_callback_t read_callback,a2dp_source_enqueue_callback_t enqueue_callback)170 void a2dp_vendor_aptx_encoder_init(
171     const tA2DP_ENCODER_INIT_PEER_PARAMS* p_peer_params,
172     A2dpCodecConfig* a2dp_codec_config,
173     a2dp_source_read_callback_t read_callback,
174     a2dp_source_enqueue_callback_t enqueue_callback) {
175   memset(&a2dp_aptx_encoder_cb, 0, sizeof(a2dp_aptx_encoder_cb));
176 
177   a2dp_aptx_encoder_cb.stats.session_start_us = time_get_os_boottime_us();
178 
179   a2dp_aptx_encoder_cb.read_callback = read_callback;
180   a2dp_aptx_encoder_cb.enqueue_callback = enqueue_callback;
181   a2dp_aptx_encoder_cb.is_peer_edr = p_peer_params->is_peer_edr;
182   a2dp_aptx_encoder_cb.peer_supports_3mbps = p_peer_params->peer_supports_3mbps;
183   a2dp_aptx_encoder_cb.peer_mtu = p_peer_params->peer_mtu;
184   a2dp_aptx_encoder_cb.timestamp = 0;
185 
186   /* aptX encoder config */
187   a2dp_aptx_encoder_cb.use_SCMS_T = false;  // TODO: should be a parameter
188 #if (BTA_AV_CO_CP_SCMS_T == TRUE)
189   a2dp_aptx_encoder_cb.use_SCMS_T = true;
190 #endif
191 
192   a2dp_aptx_encoder_cb.aptx_encoder_state =
193       osi_malloc(aptx_encoder_sizeof_params_func());
194   if (a2dp_aptx_encoder_cb.aptx_encoder_state != NULL) {
195     aptx_encoder_init_func(a2dp_aptx_encoder_cb.aptx_encoder_state, 0);
196   } else {
197     LOG_ERROR(LOG_TAG, "%s: Cannot allocate aptX encoder state", __func__);
198     // TODO: Return an error?
199   }
200 
201   // NOTE: Ignore the restart_input / restart_output flags - this initization
202   // happens when the connection is (re)started.
203   bool restart_input = false;
204   bool restart_output = false;
205   bool config_updated = false;
206   a2dp_vendor_aptx_encoder_update(a2dp_aptx_encoder_cb.peer_mtu,
207                                   a2dp_codec_config, &restart_input,
208                                   &restart_output, &config_updated);
209 }
210 
updateEncoderUserConfig(const tA2DP_ENCODER_INIT_PEER_PARAMS * p_peer_params,bool * p_restart_input,bool * p_restart_output,bool * p_config_updated)211 bool A2dpCodecConfigAptx::updateEncoderUserConfig(
212     const tA2DP_ENCODER_INIT_PEER_PARAMS* p_peer_params, bool* p_restart_input,
213     bool* p_restart_output, bool* p_config_updated) {
214   a2dp_aptx_encoder_cb.is_peer_edr = p_peer_params->is_peer_edr;
215   a2dp_aptx_encoder_cb.peer_supports_3mbps = p_peer_params->peer_supports_3mbps;
216   a2dp_aptx_encoder_cb.peer_mtu = p_peer_params->peer_mtu;
217   a2dp_aptx_encoder_cb.timestamp = 0;
218 
219   if (a2dp_aptx_encoder_cb.peer_mtu == 0) {
220     LOG_ERROR(LOG_TAG,
221               "%s: Cannot update the codec encoder for %s: "
222               "invalid peer MTU",
223               __func__, name().c_str());
224     return false;
225   }
226 
227   a2dp_vendor_aptx_encoder_update(a2dp_aptx_encoder_cb.peer_mtu, this,
228                                   p_restart_input, p_restart_output,
229                                   p_config_updated);
230   return true;
231 }
232 
233 // Update the A2DP aptX encoder.
234 // |peer_mtu| is the peer MTU.
235 // |a2dp_codec_config| is the A2DP codec to use for the update.
a2dp_vendor_aptx_encoder_update(uint16_t peer_mtu,A2dpCodecConfig * a2dp_codec_config,bool * p_restart_input,bool * p_restart_output,bool * p_config_updated)236 static void a2dp_vendor_aptx_encoder_update(uint16_t peer_mtu,
237                                             A2dpCodecConfig* a2dp_codec_config,
238                                             bool* p_restart_input,
239                                             bool* p_restart_output,
240                                             bool* p_config_updated) {
241   uint8_t codec_info[AVDT_CODEC_SIZE];
242 
243   *p_restart_input = false;
244   *p_restart_output = false;
245   *p_config_updated = false;
246   if (!a2dp_codec_config->copyOutOtaCodecConfig(codec_info)) {
247     LOG_ERROR(LOG_TAG,
248               "%s: Cannot update the codec encoder for %s: "
249               "invalid codec config",
250               __func__, a2dp_codec_config->name().c_str());
251     return;
252   }
253   const uint8_t* p_codec_info = codec_info;
254 
255   // The feeding parameters
256   tA2DP_FEEDING_PARAMS* p_feeding_params = &a2dp_aptx_encoder_cb.feeding_params;
257   p_feeding_params->sample_rate =
258       A2DP_VendorGetTrackSampleRateAptx(p_codec_info);
259   p_feeding_params->bits_per_sample =
260       a2dp_codec_config->getAudioBitsPerSample();
261   p_feeding_params->channel_count =
262       A2DP_VendorGetTrackChannelCountAptx(p_codec_info);
263   LOG_DEBUG(LOG_TAG, "%s: sample_rate=%u bits_per_sample=%u channel_count=%u",
264             __func__, p_feeding_params->sample_rate,
265             p_feeding_params->bits_per_sample, p_feeding_params->channel_count);
266   a2dp_vendor_aptx_feeding_reset();
267 }
268 
a2dp_vendor_aptx_encoder_cleanup(void)269 void a2dp_vendor_aptx_encoder_cleanup(void) {
270   osi_free(a2dp_aptx_encoder_cb.aptx_encoder_state);
271   memset(&a2dp_aptx_encoder_cb, 0, sizeof(a2dp_aptx_encoder_cb));
272 }
273 
274 //
275 // Initialize the framing parameters, and set those that don't change
276 // while streaming (e.g., 'sleep_time_ns').
277 //
aptx_init_framing_params(tAPTX_FRAMING_PARAMS * framing_params)278 static void aptx_init_framing_params(tAPTX_FRAMING_PARAMS* framing_params) {
279   framing_params->sleep_time_ns = 0;
280   framing_params->pcm_reads = 0;
281   framing_params->pcm_bytes_per_read = 0;
282   framing_params->aptx_bytes = 0;
283   framing_params->frame_size_counter = 0;
284 
285   if (a2dp_aptx_encoder_cb.feeding_params.sample_rate == 48000) {
286     if (a2dp_aptx_encoder_cb.use_SCMS_T) {
287       framing_params->sleep_time_ns = 13000000;
288     } else {
289       framing_params->sleep_time_ns = 14000000;
290     }
291   } else {
292     // Assume the sample rate is 44100
293     if (a2dp_aptx_encoder_cb.use_SCMS_T) {
294       framing_params->sleep_time_ns = 14000000;
295     } else {
296       framing_params->sleep_time_ns = 15000000;
297     }
298   }
299 
300   LOG_DEBUG(LOG_TAG, "%s: sleep_time_ns = %" PRIu64, __func__,
301             framing_params->sleep_time_ns);
302 }
303 
304 //
305 // Set frame size and transmission interval needed to stream the required
306 // sample rate using 2-DH5 packets for aptX and 2-DH3 packets for aptX-LL.
307 // With SCMS-T enabled we need to reserve room for extra headers added later.
308 // Packets are always sent at equals time intervals but to achieve the
309 // required sample rate, the frame size needs to change on occasion.
310 //
311 // Also need to specify how many of the required PCM samples are read at a
312 // time:
313 //     aptx_bytes = pcm_reads * pcm_bytes_per_read / 4
314 // and
315 //     number of aptX samples produced = pcm_bytes_per_read / 16
316 //
aptx_update_framing_params(tAPTX_FRAMING_PARAMS * framing_params)317 static void aptx_update_framing_params(tAPTX_FRAMING_PARAMS* framing_params) {
318   if (a2dp_aptx_encoder_cb.feeding_params.sample_rate == 48000) {
319     if (a2dp_aptx_encoder_cb.use_SCMS_T) {
320       framing_params->aptx_bytes = 624;
321       framing_params->pcm_bytes_per_read = 208;
322       framing_params->pcm_reads = 12;
323     } else {
324       framing_params->aptx_bytes = 672;
325       framing_params->pcm_bytes_per_read = 224;
326       framing_params->pcm_reads = 12;
327     }
328   } else {
329     // Assume the sample rate is 44100
330     if (a2dp_aptx_encoder_cb.use_SCMS_T) {
331       if (++framing_params->frame_size_counter < 20) {
332         framing_params->aptx_bytes = 616;
333         framing_params->pcm_bytes_per_read = 224;
334         framing_params->pcm_reads = 11;
335       } else {
336         framing_params->aptx_bytes = 644;
337         framing_params->pcm_bytes_per_read = 368;
338         framing_params->pcm_reads = 7;
339         framing_params->frame_size_counter = 0;
340       }
341     } else {
342       if (++framing_params->frame_size_counter < 8) {
343         framing_params->aptx_bytes = 660;
344         framing_params->pcm_bytes_per_read = 240;
345         framing_params->pcm_reads = 11;
346       } else {
347         framing_params->aptx_bytes = 672;
348         framing_params->pcm_bytes_per_read = 224;
349         framing_params->pcm_reads = 12;
350         framing_params->frame_size_counter = 0;
351       }
352     }
353   }
354 
355   LOG_VERBOSE(LOG_TAG,
356               "%s: sleep_time_ns = %" PRIu64
357               " aptx_bytes = %u "
358               "pcm_bytes_per_read = %u pcm_reads = %u frame_size_counter = %u",
359               __func__, framing_params->sleep_time_ns,
360               framing_params->aptx_bytes, framing_params->pcm_bytes_per_read,
361               framing_params->pcm_reads, framing_params->frame_size_counter);
362 }
363 
a2dp_vendor_aptx_feeding_reset(void)364 void a2dp_vendor_aptx_feeding_reset(void) {
365   aptx_init_framing_params(&a2dp_aptx_encoder_cb.framing_params);
366 }
367 
a2dp_vendor_aptx_feeding_flush(void)368 void a2dp_vendor_aptx_feeding_flush(void) {
369   aptx_init_framing_params(&a2dp_aptx_encoder_cb.framing_params);
370 }
371 
a2dp_vendor_aptx_get_encoder_interval_ms(void)372 period_ms_t a2dp_vendor_aptx_get_encoder_interval_ms(void) {
373   return a2dp_aptx_encoder_cb.framing_params.sleep_time_ns / (1000 * 1000);
374 }
375 
a2dp_vendor_aptx_send_frames(uint64_t timestamp_us)376 void a2dp_vendor_aptx_send_frames(uint64_t timestamp_us) {
377   tAPTX_FRAMING_PARAMS* framing_params = &a2dp_aptx_encoder_cb.framing_params;
378 
379   // Prepare the packet to send
380   BT_HDR* p_buf = (BT_HDR*)osi_malloc(BT_DEFAULT_BUFFER_SIZE);
381   p_buf->offset = A2DP_APTX_OFFSET;
382   p_buf->len = 0;
383   p_buf->layer_specific = 0;
384 
385   uint8_t* encoded_ptr = (uint8_t*)(p_buf + 1);
386   encoded_ptr += p_buf->offset;
387 
388   aptx_update_framing_params(framing_params);
389 
390   //
391   // Read the PCM data and encode it
392   //
393   uint16_t read_buffer16[A2DP_APTX_MAX_PCM_BYTES_PER_READ / sizeof(uint16_t)];
394   uint32_t expected_read_bytes =
395       framing_params->pcm_reads * framing_params->pcm_bytes_per_read;
396   size_t encoded_ptr_index = 0;
397   size_t pcm_bytes_encoded = 0;
398   uint32_t bytes_read = 0;
399 
400   a2dp_aptx_encoder_cb.stats.media_read_total_expected_packets++;
401   a2dp_aptx_encoder_cb.stats.media_read_total_expected_reads_count++;
402   a2dp_aptx_encoder_cb.stats.media_read_total_expected_read_bytes +=
403       expected_read_bytes;
404 
405   LOG_VERBOSE(LOG_TAG, "%s: PCM read of size %u", __func__,
406               expected_read_bytes);
407   bytes_read = a2dp_aptx_encoder_cb.read_callback((uint8_t*)read_buffer16,
408                                                   expected_read_bytes);
409   a2dp_aptx_encoder_cb.stats.media_read_total_actual_read_bytes += bytes_read;
410   if (bytes_read < expected_read_bytes) {
411     LOG_WARN(LOG_TAG,
412              "%s: underflow at PCM reading: read %u bytes instead of %u",
413              __func__, bytes_read, expected_read_bytes);
414     a2dp_aptx_encoder_cb.stats.media_read_total_dropped_packets++;
415     osi_free(p_buf);
416     return;
417   }
418   a2dp_aptx_encoder_cb.stats.media_read_total_actual_reads_count++;
419 
420   for (uint32_t reads = 0, offset = 0; reads < framing_params->pcm_reads;
421        reads++, offset +=
422                 (framing_params->pcm_bytes_per_read / sizeof(uint16_t))) {
423     pcm_bytes_encoded += aptx_encode_16bit(framing_params, &encoded_ptr_index,
424                                            read_buffer16 + offset, encoded_ptr);
425   }
426 
427   // Compute the number of encoded bytes
428   const int COMPRESSION_RATIO = 4;
429   size_t encoded_bytes = pcm_bytes_encoded / COMPRESSION_RATIO;
430   p_buf->len += encoded_bytes;
431   LOG_VERBOSE(LOG_TAG, "%s: encoded %zu PCM bytes to %zu", __func__,
432               pcm_bytes_encoded, encoded_bytes);
433 
434   // Update the RTP timestamp
435   *((uint32_t*)(p_buf + 1)) = a2dp_aptx_encoder_cb.timestamp;
436   const uint8_t BYTES_PER_FRAME = 2;
437   uint32_t rtp_timestamp =
438       (pcm_bytes_encoded / a2dp_aptx_encoder_cb.feeding_params.channel_count) /
439       BYTES_PER_FRAME;
440   a2dp_aptx_encoder_cb.timestamp += rtp_timestamp;
441 
442   if (p_buf->len > 0) {
443     a2dp_aptx_encoder_cb.enqueue_callback(p_buf, 1, bytes_read);
444   } else {
445     a2dp_aptx_encoder_cb.stats.media_read_total_dropped_packets++;
446     osi_free(p_buf);
447   }
448 }
449 
aptx_encode_16bit(tAPTX_FRAMING_PARAMS * framing_params,size_t * data_out_index,uint16_t * data16_in,uint8_t * data_out)450 static size_t aptx_encode_16bit(tAPTX_FRAMING_PARAMS* framing_params,
451                                 size_t* data_out_index, uint16_t* data16_in,
452                                 uint8_t* data_out) {
453   size_t pcm_bytes_encoded = 0;
454   size_t frame = 0;
455 
456   for (size_t aptx_samples = 0;
457        aptx_samples < framing_params->pcm_bytes_per_read / 16; aptx_samples++) {
458     uint32_t pcmL[4];
459     uint32_t pcmR[4];
460     uint16_t encoded_sample[2];
461 
462     for (size_t i = 0, j = frame; i < 4; i++, j++) {
463       pcmL[i] = (uint16_t) * (data16_in + (2 * j));
464       pcmR[i] = (uint16_t) * (data16_in + ((2 * j) + 1));
465     }
466 
467     aptx_encoder_encode_stereo_func(a2dp_aptx_encoder_cb.aptx_encoder_state,
468                                     &pcmL, &pcmR, &encoded_sample);
469 
470     data_out[*data_out_index + 0] = (uint8_t)((encoded_sample[0] >> 8) & 0xff);
471     data_out[*data_out_index + 1] = (uint8_t)((encoded_sample[0] >> 0) & 0xff);
472     data_out[*data_out_index + 2] = (uint8_t)((encoded_sample[1] >> 8) & 0xff);
473     data_out[*data_out_index + 3] = (uint8_t)((encoded_sample[1] >> 0) & 0xff);
474 
475     frame += 4;
476     pcm_bytes_encoded += 16;
477     *data_out_index += 4;
478   }
479 
480   return pcm_bytes_encoded;
481 }
482 
encoderIntervalMs() const483 period_ms_t A2dpCodecConfigAptx::encoderIntervalMs() const {
484   return a2dp_vendor_aptx_get_encoder_interval_ms();
485 }
486 
getEffectiveMtu() const487 int A2dpCodecConfigAptx::getEffectiveMtu() const {
488   return a2dp_aptx_encoder_cb.peer_mtu;
489 }
490 
debug_codec_dump(int fd)491 void A2dpCodecConfigAptx::debug_codec_dump(int fd) {
492   a2dp_aptx_encoder_stats_t* stats = &a2dp_aptx_encoder_cb.stats;
493 
494   A2dpCodecConfig::debug_codec_dump(fd);
495 
496   dprintf(fd,
497           "  Packet counts (expected/dropped)                        : %zu / "
498           "%zu\n",
499           stats->media_read_total_expected_packets,
500           stats->media_read_total_dropped_packets);
501 
502   dprintf(fd,
503           "  PCM read counts (expected/actual)                       : %zu / "
504           "%zu\n",
505           stats->media_read_total_expected_reads_count,
506           stats->media_read_total_actual_reads_count);
507 
508   dprintf(fd,
509           "  PCM read bytes (expected/actual)                        : %zu / "
510           "%zu\n",
511           stats->media_read_total_expected_read_bytes,
512           stats->media_read_total_actual_read_bytes);
513 }
514