hal: add split A2DP sink support

- Add changes to support BT IPC sink library.
- Add mixer control support to send decoder configuration for
  split A2DP sink usecase.
- Add hw loopback support for split A2DP sink usecase.

Change-Id: I3b015385ce1fdd5c0cbf512fe06b73143a32ae2d
diff --git a/hal/msm8974/platform.c b/hal/msm8974/platform.c
index 390a9eb..05c51d9 100644
--- a/hal/msm8974/platform.c
+++ b/hal/msm8974/platform.c
@@ -491,6 +491,7 @@
     [SND_DEVICE_IN_BT_SCO_MIC_NREC] = "bt-sco-mic",
     [SND_DEVICE_IN_BT_SCO_MIC_WB] = "bt-sco-mic-wb",
     [SND_DEVICE_IN_BT_SCO_MIC_WB_NREC] = "bt-sco-mic-wb",
+    [SND_DEVICE_IN_BT_A2DP] = "bt-a2dp-cap",
     [SND_DEVICE_IN_CAMCORDER_MIC] = "camcorder-mic",
     [SND_DEVICE_IN_VOICE_DMIC] = "voice-dmic-ef",
     [SND_DEVICE_IN_VOICE_SPEAKER_DMIC] = "voice-speaker-dmic-ef",
@@ -660,6 +661,7 @@
     [SND_DEVICE_IN_BT_SCO_MIC_NREC] = 122,
     [SND_DEVICE_IN_BT_SCO_MIC_WB] = 38,
     [SND_DEVICE_IN_BT_SCO_MIC_WB_NREC] = 123,
+    [SND_DEVICE_IN_BT_A2DP] = 21,
     [SND_DEVICE_IN_CAMCORDER_MIC] = 4,
     [SND_DEVICE_IN_VOICE_DMIC] = 41,
     [SND_DEVICE_IN_VOICE_SPEAKER_DMIC] = 43,
@@ -811,6 +813,7 @@
     {TO_NAME_INDEX(SND_DEVICE_IN_BT_SCO_MIC_NREC)},
     {TO_NAME_INDEX(SND_DEVICE_IN_BT_SCO_MIC_WB)},
     {TO_NAME_INDEX(SND_DEVICE_IN_BT_SCO_MIC_WB_NREC)},
+    {TO_NAME_INDEX(SND_DEVICE_IN_BT_A2DP)},
     {TO_NAME_INDEX(SND_DEVICE_IN_CAMCORDER_MIC)},
     {TO_NAME_INDEX(SND_DEVICE_IN_VOICE_DMIC)},
     {TO_NAME_INDEX(SND_DEVICE_IN_VOICE_SPEAKER_DMIC)},
@@ -1423,6 +1426,7 @@
     backend_tag_table[SND_DEVICE_OUT_VOICE_SPEAKER_VBAT] = strdup("voice-speaker-vbat");
     backend_tag_table[SND_DEVICE_OUT_VOICE_SPEAKER_2_VBAT] = strdup("voice-speaker-2-vbat");
     backend_tag_table[SND_DEVICE_OUT_BT_A2DP] = strdup("bt-a2dp");
+    backend_tag_table[SND_DEVICE_IN_BT_A2DP] = strdup("bt-a2dp-cap");
     backend_tag_table[SND_DEVICE_OUT_SPEAKER_AND_BT_A2DP] = strdup("speaker-and-bt-a2dp");
     backend_tag_table[SND_DEVICE_OUT_VOICE_SPEAKER_AND_VOICE_HEADPHONES] = strdup("speaker-and-headphones");
     backend_tag_table[SND_DEVICE_OUT_VOICE_SPEAKER_AND_VOICE_ANC_HEADSET] = strdup("speaker-and-headphones");
@@ -1517,6 +1521,7 @@
     hw_interface_table[SND_DEVICE_IN_BT_SCO_MIC_NREC] = strdup("SLIMBUS_7_TX");
     hw_interface_table[SND_DEVICE_IN_BT_SCO_MIC_WB] = strdup("SLIMBUS_7_TX");
     hw_interface_table[SND_DEVICE_IN_BT_SCO_MIC_WB_NREC] = strdup("SLIMBUS_7_TX");
+    hw_interface_table[SND_DEVICE_IN_BT_A2DP] = strdup("SLIMBUS_7_TX");
     hw_interface_table[SND_DEVICE_IN_CAMCORDER_MIC] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_VOICE_DMIC] = strdup("SLIMBUS_0_TX");
     hw_interface_table[SND_DEVICE_IN_VOICE_SPEAKER_DMIC] = strdup("SLIMBUS_0_TX");
@@ -4627,6 +4632,8 @@
             }
         } else if (in_device & AUDIO_DEVICE_IN_SPDIF) {
             snd_device = SND_DEVICE_IN_SPDIF;
+        } else if (in_device & AUDIO_DEVICE_IN_BLUETOOTH_A2DP) {
+            snd_device = SND_DEVICE_IN_BT_A2DP;
         } else if (in_device & AUDIO_DEVICE_IN_AUX_DIGITAL) {
             snd_device = SND_DEVICE_IN_HDMI_MIC;
         } else if (in_device & AUDIO_DEVICE_IN_HDMI_ARC) {
@@ -6181,6 +6188,7 @@
     if (snd_device == SND_DEVICE_OUT_BT_A2DP ||
         snd_device == SND_DEVICE_OUT_BT_SCO ||
         snd_device == SND_DEVICE_OUT_BT_SCO_WB ||
+        snd_device == SND_DEVICE_IN_BT_A2DP ||
         snd_device == SND_DEVICE_OUT_AFE_PROXY) {
         backend_change = false;
         return backend_change;