hal: Add support for haptics audio usecase

Add support to create haptics and audio pcm streams for
haptic audio usecase. Separate haptic and audio data from
audio buffer and write it to respective pcm streams.

Bug: 112439981
Test: make
Change-Id: Id59179461edf695fd4794c51426e6fcae6c2e8dc
diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index 657a627..ccf922e 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -131,6 +131,26 @@
     .avail_min = LOW_LATENCY_OUTPUT_PERIOD_SIZE / 4,
 };
 
+struct pcm_config pcm_config_haptics_audio = {
+    .channels = 1,
+    .rate = DEFAULT_OUTPUT_SAMPLING_RATE,
+    .period_size = LOW_LATENCY_OUTPUT_PERIOD_SIZE,
+    .period_count = LOW_LATENCY_OUTPUT_PERIOD_COUNT,
+    .format = PCM_FORMAT_S16_LE,
+    .start_threshold = LOW_LATENCY_OUTPUT_PERIOD_SIZE / 4,
+    .stop_threshold = INT_MAX,
+    .avail_min = LOW_LATENCY_OUTPUT_PERIOD_SIZE / 4,
+};
+
+struct pcm_config pcm_config_haptics = {
+    .channels = 1,
+    .rate = DEFAULT_OUTPUT_SAMPLING_RATE,
+    .period_count = 2,
+    .format = PCM_FORMAT_S16_LE,
+    .stop_threshold = INT_MAX,
+    .avail_min = 0,
+};
+
 static int af_period_multiplier = 4;
 struct pcm_config pcm_config_rt = {
     .channels = DEFAULT_CHANNEL_COUNT,
@@ -256,6 +276,7 @@
 const char * const use_case_table[AUDIO_USECASE_MAX] = {
     [USECASE_AUDIO_PLAYBACK_DEEP_BUFFER] = "deep-buffer-playback",
     [USECASE_AUDIO_PLAYBACK_LOW_LATENCY] = "low-latency-playback",
+    [USECASE_AUDIO_PLAYBACK_WITH_HAPTICS] = "audio-with-haptics-playback",
     [USECASE_AUDIO_PLAYBACK_HIFI] = "hifi-playback",
     [USECASE_AUDIO_PLAYBACK_OFFLOAD] = "compress-offload-playback",
     [USECASE_AUDIO_PLAYBACK_TTS] = "audio-tts-playback",
@@ -2235,6 +2256,41 @@
     return ret;
 }
 
+struct pcm* pcm_open_prepare_helper(unsigned int snd_card, unsigned int pcm_device_id,
+                                   unsigned int flags, unsigned int pcm_open_retry_count,
+                                   struct pcm_config *config)
+{
+    struct pcm* pcm = NULL;
+
+    while (1) {
+        pcm = pcm_open(snd_card, pcm_device_id, flags, config);
+        if (pcm == NULL || !pcm_is_ready(pcm)) {
+            ALOGE("%s: %s", __func__, pcm_get_error(pcm));
+            if (pcm != NULL) {
+                pcm_close(pcm);
+                pcm = NULL;
+            }
+            if (pcm_open_retry_count-- == 0)
+                return NULL;
+
+            usleep(PROXY_OPEN_WAIT_TIME * 1000);
+            continue;
+        }
+        break;
+    }
+
+    if (pcm_is_ready(pcm)) {
+        int ret = pcm_prepare(pcm);
+        if (ret < 0) {
+            ALOGE("%s: pcm_prepare returned %d", __func__, ret);
+            pcm_close(pcm);
+            pcm = NULL;
+        }
+    }
+
+    return pcm;
+}
+
 int start_output_stream(struct stream_out *out)
 {
     int ret = 0;
@@ -2242,8 +2298,10 @@
     struct audio_device *adev = out->dev;
     bool a2dp_combo = false;
 
-    ALOGV("%s: enter: usecase(%d: %s) devices(%#x)",
-          __func__, out->usecase, use_case_table[out->usecase], out->devices);
+    ALOGV("%s: enter: usecase(%d: %s) %s devices(%#x)",
+          __func__, out->usecase, use_case_table[out->usecase],
+          out->usecase == USECASE_AUDIO_PLAYBACK_WITH_HAPTICS ? "(with haptics)" : "",
+          out->devices);
 
     if (out->card_status == CARD_STATUS_OFFLINE ||
         adev->card_status == CARD_STATUS_OFFLINE) {
@@ -2363,34 +2421,27 @@
             flags |= PCM_MMAP | PCM_NOIRQ;
         }
 
-        while (1) {
-            out->pcm = pcm_open(adev->snd_card, out->pcm_device_id,
-                               flags, &out->config);
-            if (out->pcm == NULL || !pcm_is_ready(out->pcm)) {
-                ALOGE("%s: %s", __func__, pcm_get_error(out->pcm));
-                if (out->pcm != NULL) {
-                    pcm_close(out->pcm);
-                    out->pcm = NULL;
-                }
-                if (pcm_open_retry_count-- == 0) {
-                    ret = -EIO;
-                    goto error_open;
-                }
-                usleep(PROXY_OPEN_WAIT_TIME * 1000);
-                continue;
-            }
-            break;
+        out->pcm = pcm_open_prepare_helper(adev->snd_card, out->pcm_device_id,
+                                       flags, pcm_open_retry_count,
+                                       &(out->config));
+        if (out->pcm == NULL) {
+           ret = -EIO;
+           goto error_open;
         }
-        ALOGV("%s: pcm_prepare", __func__);
-        if (pcm_is_ready(out->pcm)) {
-            ret = pcm_prepare(out->pcm);
-            if (ret < 0) {
-                ALOGE("%s: pcm_prepare returned %d", __func__, ret);
-                pcm_close(out->pcm);
-                out->pcm = NULL;
-                goto error_open;
+
+        if (out->usecase == USECASE_AUDIO_PLAYBACK_WITH_HAPTICS) {
+            if (adev->haptic_pcm != NULL) {
+                pcm_close(adev->haptic_pcm);
+                adev->haptic_pcm = NULL;
             }
+            adev->haptic_pcm = pcm_open_prepare_helper(adev->snd_card,
+                                   adev->haptic_pcm_device_id,
+                                   flags, pcm_open_retry_count,
+                                   &(adev->haptics_config));
+            // failure to open haptics pcm shouldnt stop audio,
+            // so do not close audio pcm in case of error
         }
+
         if (out->realtime) {
             ret = pcm_start(out->pcm);
             if (ret < 0) {
@@ -2401,6 +2452,7 @@
             }
         }
     }
+
     register_out_stream(out);
     audio_streaming_hint_end();
     audio_extn_perf_lock_release();
@@ -2414,13 +2466,17 @@
     // consider a scenario where on pause lower layers are tear down.
     // so on resume, swap mixer control need to be sent only when
     // backend is active, hence rather than sending from enable device
-    // sending it from start of streamtream
+    // sending it from start of stream
 
     platform_set_swap_channels(adev, true);
 
     ALOGV("%s: exit", __func__);
     return 0;
 error_open:
+    if (adev->haptic_pcm) {
+        pcm_close(adev->haptic_pcm);
+        adev->haptic_pcm = NULL;
+    }
     audio_streaming_hint_end();
     audio_extn_perf_lock_release();
     stop_output_stream(out);
@@ -2594,6 +2650,19 @@
             if (out->pcm) {
                 pcm_close(out->pcm);
                 out->pcm = NULL;
+
+                if (out->usecase == USECASE_AUDIO_PLAYBACK_WITH_HAPTICS) {
+                    if (adev->haptic_pcm) {
+                        pcm_close(adev->haptic_pcm);
+                        adev->haptic_pcm = NULL;
+                    }
+
+                    if (adev->haptic_buffer != NULL) {
+                        free(adev->haptic_buffer);
+                        adev->haptic_buffer = NULL;
+                        adev->haptic_buffer_size = 0;
+                    }
+                }
             }
             if (out->usecase == USECASE_AUDIO_PLAYBACK_MMAP) {
                 do_stop = out->playback_started;
@@ -3294,11 +3363,77 @@
             request_out_focus(out, ns);
 
             bool use_mmap = is_mmap_usecase(out->usecase) || out->realtime;
-            if (use_mmap)
+            if (use_mmap) {
                 ret = pcm_mmap_write(out->pcm, (void *)buffer, bytes_to_write);
-            else
-                ret = pcm_write(out->pcm, (void *)buffer, bytes_to_write);
+            } else {
+                if (out->usecase == USECASE_AUDIO_PLAYBACK_WITH_HAPTICS) {
+                    size_t channel_count = audio_channel_count_from_out_mask(out->channel_mask);
+                    size_t bytes_per_sample = audio_bytes_per_sample(out->format);
+                    size_t frame_size = channel_count * bytes_per_sample;
+                    size_t frame_count = bytes_to_write / frame_size;
 
+                    bool force_haptic_path =
+                         property_get_bool("vendor.audio.test_haptic", false);
+
+                    // extract Haptics data from Audio buffer
+                    bool   alloc_haptic_buffer = false;
+                    int    haptic_channel_count = adev->haptics_config.channels;
+                    size_t haptic_frame_size = bytes_per_sample * haptic_channel_count;
+                    size_t audio_frame_size = frame_size - haptic_frame_size;
+                    size_t total_haptic_buffer_size = frame_count * haptic_frame_size;
+
+                    if (adev->haptic_buffer == NULL) {
+                        alloc_haptic_buffer = true;
+                    } else if (adev->haptic_buffer_size < total_haptic_buffer_size) {
+                        free(adev->haptic_buffer);
+                        adev->haptic_buffer_size = 0;
+                        alloc_haptic_buffer = true;
+                    }
+
+                    if (alloc_haptic_buffer) {
+                        adev->haptic_buffer = (uint8_t *)calloc(1, total_haptic_buffer_size);
+                        adev->haptic_buffer_size = total_haptic_buffer_size;
+                    }
+
+                    size_t src_index = 0, aud_index = 0, hap_index = 0;
+                    uint8_t *audio_buffer = (uint8_t *)buffer;
+                    uint8_t *haptic_buffer  = adev->haptic_buffer;
+
+                    // This is required for testing only. This works for stereo data only.
+                    // One channel is fed to audio stream and other to haptic stream for testing.
+                    if (force_haptic_path) {
+                       audio_frame_size = haptic_frame_size = bytes_per_sample;
+                    }
+
+                    for (size_t i = 0; i < frame_count; i++) {
+                        for (size_t j = 0; j < audio_frame_size; j++)
+                            audio_buffer[aud_index++] = audio_buffer[src_index++];
+
+                        for (size_t j = 0; j < haptic_frame_size; j++)
+                            haptic_buffer[hap_index++] = audio_buffer[src_index++];
+                        }
+
+                        // This is required for testing only.
+                        // Discard haptic channel data.
+                        if (force_haptic_path) {
+                            src_index += haptic_frame_size;
+                    }
+
+                    // write to audio pipeline
+                    ret = pcm_write(out->pcm,
+                                    (void *)audio_buffer,
+                                    frame_count * audio_frame_size);
+
+                    // write to haptics pipeline
+                    if (adev->haptic_pcm)
+                        ret = pcm_write(adev->haptic_pcm,
+                                        (void *)adev->haptic_buffer,
+                                        frame_count * haptic_frame_size);
+
+                } else {
+                    ret = pcm_write(out->pcm, (void *)buffer, bytes_to_write);
+                }
+            }
             release_out_focus(out, ns);
         } else {
             LOG_ALWAYS_FATAL("out->pcm is NULL after starting output stream");
@@ -4391,6 +4526,8 @@
     bool is_hdmi = devices & AUDIO_DEVICE_OUT_AUX_DIGITAL;
     bool is_usb_dev = audio_is_usb_out_device(devices) &&
                       (devices != AUDIO_DEVICE_OUT_USB_ACCESSORY);
+    bool force_haptic_path =
+            property_get_bool("vendor.audio.test_haptic", false);
 
     if (is_usb_dev && !is_usb_ready(adev, true /* is_playback */)) {
         return -ENOSYS;
@@ -4398,6 +4535,7 @@
 
     ALOGV("%s: enter: format(%#x) sample_rate(%d) channel_mask(%#x) devices(%#x) flags(%#x)",
           __func__, config->format, config->sample_rate, config->channel_mask, devices, flags);
+
     *stream_out = NULL;
     out = (struct stream_out *)calloc(1, sizeof(struct stream_out));
 
@@ -4728,8 +4866,24 @@
             out->stream.create_mmap_buffer = out_create_mmap_buffer;
             out->stream.get_mmap_position = out_get_mmap_position;
         } else {
-            out->usecase = USECASE_AUDIO_PLAYBACK_LOW_LATENCY;
-            out->config = pcm_config_low_latency;
+            if (config->channel_mask & AUDIO_CHANNEL_HAPTIC_ALL) {
+                out->usecase = USECASE_AUDIO_PLAYBACK_WITH_HAPTICS;
+                adev->haptic_pcm_device_id = platform_get_haptics_pcm_device_id();
+                if (adev->haptic_pcm_device_id < 0) {
+                    ALOGE("%s: Invalid Haptics pcm device id(%d) for the usecase(%d)",
+                          __func__, adev->haptic_pcm_device_id, out->usecase);
+                    ret = -ENOSYS;
+                    goto error_open;
+                }
+                out->config = pcm_config_haptics_audio;
+                if (force_haptic_path)
+                    adev->haptics_config = pcm_config_haptics_audio;
+                else
+                    adev->haptics_config = pcm_config_haptics;
+            } else {
+                out->usecase = USECASE_AUDIO_PLAYBACK_LOW_LATENCY;
+                out->config = pcm_config_low_latency;
+            }
         }
 
         if (config->sample_rate == 0) {
@@ -4737,11 +4891,13 @@
         } else {
             out->sample_rate = config->sample_rate;
         }
+
         if (config->channel_mask == AUDIO_CHANNEL_NONE) {
             out->channel_mask = audio_channel_out_mask_from_count(out->config.channels);
         } else {
             out->channel_mask = config->channel_mask;
         }
+
         if (config->format == AUDIO_FORMAT_DEFAULT)
             out->format = audio_format_from_pcm_format(out->config.format);
         else if (!audio_is_linear_pcm(config->format)) {
@@ -4753,8 +4909,25 @@
         }
 
         out->config.rate = out->sample_rate;
-        out->config.channels =
-                audio_channel_count_from_out_mask(out->channel_mask);
+
+        if (config->channel_mask & AUDIO_CHANNEL_HAPTIC_ALL) {
+             out->config.channels =
+                audio_channel_count_from_out_mask(out->channel_mask &
+                                                  ~AUDIO_CHANNEL_HAPTIC_ALL);
+
+             if (force_haptic_path) {
+                 out->config.channels = 1;
+                 adev->haptics_config.channels = 1;
+             } else {
+                 adev->haptics_config.channels =
+                     audio_channel_count_from_out_mask(out->channel_mask &
+                                                      AUDIO_CHANNEL_HAPTIC_ALL);
+             }
+        } else {
+             out->config.channels =
+                    audio_channel_count_from_out_mask(out->channel_mask);
+        }
+
         if (out->format != audio_format_from_pcm_format(out->config.format)) {
             out->config.format = pcm_format_from_audio_format(out->format);
         }