device/bluetooth: Add bluetooth suspend notifier flag

ChromeOS BlueZ is adding better support for system suspend and it can be
enabled by setting the UseKernelSuspendNotifier property. Add a
BluetoothKernelSuspendNotifier feature flag, expose it in chrome://flags
and use it in device/bluetooth to enable or disable the feature when the
adapter becomes available.

BUG=b:147884615
TEST=Built for Sarien, deploy_chrome to physical device, toggled flag in
     guest mode while running dbus-monitor to confirm property changes.
R=hansberry,mcchou

Change-Id: I6cdc874e2adaa7fb59435d1768fb29bffe4e424a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2029258Reviewed-by: Miao-chen Chou <mcchou@chromium.org>
Reviewed-by: Ryan Hansberry <hansberry@chromium.org>
Commit-Queue: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742908}

chrome/browser/about_flags.cc

@@ -1858,6 +1858,10 @@ const FeatureEntry kFeatureEntries[] = {
      kOsCrOS,
      FEATURE_VALUE_TYPE(
          chromeos::features::kBluetoothAggressiveAppearanceFilter)},
+    {"bluetooth-kernel-suspend-notifier",
+     flag_descriptions::kBluetoothKernelSuspendNotifierName,
+     flag_descriptions::kBluetoothKernelSuspendNotifierDescription, kOsCrOS,
+     FEATURE_VALUE_TYPE(chromeos::features::kBluetoothKernelSuspendNotifier)},
     {"cryptauth-v2-device-activity-status",
      flag_descriptions::kCryptAuthV2DeviceActivityStatusName,
      flag_descriptions::kCryptAuthV2DeviceActivityStatusDescription, kOsCrOS,

chrome/browser/flag-metadata.json

@@ -370,6 +370,11 @@
     "owners": [ "hansberry", "cros-system-services@google.com" ],
     "expiry_milestone": 85
   },
+  {
+    "name": "bluetooth-kernel-suspend-notifier",
+    "owners": [ "abhishekpandit", "chromeos-bluetooth@google.com" ],
+    "expiry_milestone": 83
+  },
   {
     "name": "BundledConnectionHelp",
     "owners": [ "carlosil" ],

chrome/browser/flag_descriptions.cc

@@ -3093,6 +3093,12 @@ const char kBluetoothAggressiveAppearanceFilterDescription[] =
     "Enables a more aggressive Bluetooth filter in the UI to hide devices that "
     "likely cannot be connected to.";
 
+const char kBluetoothKernelSuspendNotifierName[] =
+    "Bluetooth kernel suspend notifier handler";
+const char kBluetoothKernelSuspendNotifierDescription[] =
+    "Enables the Bluetooth kernel suspend notifier which will allow wake from "
+    "suspend using Bluetooth HID devices.";
+
 const char kCameraSystemWebAppName[] = "Camera System Web App";
 const char kCameraSystemWebAppDescription[] =
     "Run the Chrome Camera App as a System Web App.";

chrome/browser/flag_descriptions.h

@@ -1782,6 +1782,9 @@ extern const char kAshSwipingFromLeftEdgeToGoBackDescription[];
 extern const char kBluetoothAggressiveAppearanceFilterName[];
 extern const char kBluetoothAggressiveAppearanceFilterDescription[];
 
+extern const char kBluetoothKernelSuspendNotifierName[];
+extern const char kBluetoothKernelSuspendNotifierDescription[];
+
 extern const char kCameraSystemWebAppName[];
 extern const char kCameraSystemWebAppDescription[];
 

chromeos/constants/chromeos_features.cc

@@ -42,6 +42,10 @@ const base::Feature kBluetoothAggressiveAppearanceFilter{
 const base::Feature kBluetoothPhoneFilter{"BluetoothPhoneFilter",
                                           base::FEATURE_ENABLED_BY_DEFAULT};
 
+// Enables or disables using the kernel suspend notifier instead of powerd.
+const base::Feature kBluetoothKernelSuspendNotifier{
+    "BluetoothKernelSuspendNotifier", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // Feature containing param to block provided long term keys.
 const base::Feature kBlueZLongTermKeyBlocklist{
     "BlueZLongTermKeyBlocklist", base::FEATURE_DISABLED_BY_DEFAULT};

chromeos/constants/chromeos_features.h

@@ -28,6 +28,8 @@ extern const base::Feature kBluetoothAggressiveAppearanceFilter;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kBluetoothPhoneFilter;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
+extern const base::Feature kBluetoothKernelSuspendNotifier;
+COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const base::Feature kBlueZLongTermKeyBlocklist;
 COMPONENT_EXPORT(CHROMEOS_CONSTANTS)
 extern const char kBlueZLongTermKeyBlocklistParamName[];

device/bluetooth/bluez/bluetooth_adapter_bluez.cc

@@ -15,6 +15,7 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback_helpers.h"
+#include "base/feature_list.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
@@ -25,6 +26,7 @@
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "components/device_event_log/device_event_log.h"
+#include "device/base/features.h"
 #include "device/bluetooth/bluetooth_common.h"
 #include "device/bluetooth/bluetooth_device.h"
 #include "device/bluetooth/bluetooth_discovery_session_outcome.h"
@@ -50,6 +52,7 @@
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
 #if defined(OS_CHROMEOS)
+#include "chromeos/constants/chromeos_features.h"
 #include "chromeos/constants/devicetype.h"
 #include "device/bluetooth/bluetooth_adapter_factory.h"
 #include "device/bluetooth/chromeos/bluetooth_utils.h"
@@ -1059,6 +1062,10 @@ void BluetoothAdapterBlueZ::SetAdapter(const dbus::ObjectPath& object_path) {
   if (properties->discovering.value())
     DiscoveringChanged(true);
 
+#if defined(OS_CHROMEOS)
+  SetChromeOSKernelSuspendNotifier(properties);
+#endif
+
   std::vector<dbus::ObjectPath> device_paths =
       bluez::BluezDBusManager::Get()
           ->GetBluetoothDeviceClient()
@@ -1098,6 +1105,25 @@ void BluetoothAdapterBlueZ::SetStandardChromeOSAdapterName() {
                              base::PersistentHash(address) & 0xFFFF);
   SetName(alias, base::DoNothing(), base::DoNothing());
 }
+
+// If the property is available, set the value according to the feature flag.
+void BluetoothAdapterBlueZ::SetChromeOSKernelSuspendNotifier(
+    bluez::BluetoothAdapterClient::Properties* properties) {
+  if (!properties->use_kernel_suspend_notifier.is_valid())
+    return;
+
+  bool use_notifier = base::FeatureList::IsEnabled(
+      chromeos::features::kBluetoothKernelSuspendNotifier);
+
+  base::OnceCallback<void(bool)> cb = base::BindOnce(
+      [](bool value, bool success) {
+        if (!success) {
+          BLUETOOTH_LOG(ERROR) << "Failed to set suspend notifier to " << value;
+        }
+      },
+      use_notifier);
+  properties->use_kernel_suspend_notifier.Set(use_notifier, std::move(cb));
+}
 #endif
 
 void BluetoothAdapterBlueZ::RemoveAdapter() {

device/bluetooth/bluez/bluetooth_adapter_bluez.h

@@ -351,6 +351,10 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothAdapterBlueZ final
 #if defined(OS_CHROMEOS)
   // Set the adapter name to one chosen from the system information.
   void SetStandardChromeOSAdapterName();
+
+  // Set the kernel suspend notifier property based off value of chrome://flags.
+  void SetChromeOSKernelSuspendNotifier(
+      bluez::BluetoothAdapterClient::Properties* properties);
 #endif
 
   // Remove the currently tracked adapter. IsPresent() will return false after

device/bluetooth/dbus/bluetooth_adapter_client.cc

@@ -182,6 +182,8 @@ BluetoothAdapterClient::Properties::Properties(
   RegisterProperty(bluetooth_adapter::kDiscoveringProperty, &discovering);
   RegisterProperty(bluetooth_adapter::kUUIDsProperty, &uuids);
   RegisterProperty(bluetooth_adapter::kModaliasProperty, &modalias);
+  RegisterProperty(bluetooth_adapter::kUseSuspendNotifierProperty,
+                   &use_kernel_suspend_notifier);
 }
 
 BluetoothAdapterClient::Properties::~Properties() = default;

device/bluetooth/dbus/bluetooth_adapter_client.h

@@ -106,6 +106,10 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothAdapterClient : public BluezDBusClient {
     // Local Device ID information in Linux kernel modalias format. Read-only.
     dbus::Property<std::string> modalias;
 
+    // Flag to enable usage of kernel suspend notifier.
+    // TODO(b/149795111): Remove once feature is default behavior in stable.
+    dbus::Property<bool> use_kernel_suspend_notifier;
+
     Properties(dbus::ObjectProxy* object_proxy,
                const std::string& interface_name,
                const PropertyChangedCallback& callback);

tools/metrics/histograms/enums.xml

@@ -37081,6 +37081,7 @@ from previous Chrome versions.
   <int value="-1939003674" label="NetworkServiceInProcess:disabled"/>
   <int value="-1938263248" label="enable-extension-info-dialog"/>
   <int value="-1937077699" label="http-form-warning"/>
+  <int value="-1936630125" label="BluetoothKernelSuspendNotifier:enabled"/>
   <int value="-1936032607" label="enable-experimental-webassembly-features"/>
   <int value="-1934661084" label="ForceUnifiedConsentBump:disabled"/>
   <int value="-1933425042" label="OfflinePreviews:enabled"/>
@@ -37452,6 +37453,7 @@ from previous Chrome versions.
   <int value="-1472825316" label="ContextualSearchLongpressResolve:enabled"/>
   <int value="-1471021059"
       label="OmniboxUIExperimentShowSuggestionFavicons:disabled"/>
+  <int value="-1470178735" label="BluetoothKernelSuspendNotifier:disabled"/>
   <int value="-1469536698" label="ChromeHomeDoodle:enabled"/>
   <int value="-1469228683" label="QuickUnlockPinSignin:disabled"/>
   <int value="-1468126425" label="ResourceLoadScheduler:disabled"/>