Lower the audio device priority for bluetooth mic

chromeos/audio/audio_device.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chromeos/audio/audio_device.h"
 
 #include "base/format_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 
 namespace chromeos {
 
 namespace {
 
 // Get the priority for a particular device type. The priority returned
 // will be between 0 to 3, the higher number meaning a higher priority.
-uint8 GetDevicePriority(AudioDeviceType type) {
+uint8 GetDevicePriority(AudioDeviceType type, bool is_input) {
+  // Lower the priority of bluetooth mic to prevent unexpected bad eperience
+  // to user because of bluetooth audio profile switching. Make priority to
+  // zero so this mic will never be automatically chosen.
+  if (type == AUDIO_TYPE_BLUETOOTH && is_input)
+    return 0;
   switch (type) {
     case AUDIO_TYPE_HEADPHONE:
     case AUDIO_TYPE_MIC:
     case AUDIO_TYPE_USB:
     case AUDIO_TYPE_BLUETOOTH:
       return 3;
     case AUDIO_TYPE_HDMI:
       return 2;
     case AUDIO_TYPE_INTERNAL_SPEAKER:
     case AUDIO_TYPE_INTERNAL_MIC:
@@ skipping 82 matching lines @@
 
 AudioDevice::AudioDevice(const AudioNode& node) {
   is_input = node.is_input;
   id = node.id;
   type = GetAudioType(node.type);
   if (!node.name.empty() && node.name != "(default)")
     display_name = node.name;
   else
     display_name = node.device_name;
   device_name = node.device_name;
-  priority = GetDevicePriority(type);
+  priority = GetDevicePriority(type, node.is_input);
   active = node.active;
   plugged_time = node.plugged_time;
 }
 
 std::string AudioDevice::ToString() const {
   std::string result;
   base::StringAppendF(&result,
                       "is_input = %s ",
                       is_input ? "true" : "false");
   base::StringAppendF(&result,
@@ skipping 12 matching lines @@
                       "active = %s ",
                       active ? "true" : "false");
   base::StringAppendF(&result,
                       "plugged_time= %s ",
                       base::Uint64ToString(plugged_time).c_str());
 
   return result;
 }
 
 }  // namespace chromeos