Android11 热点开启流程

文章目录

Android11 热点开启流程
- 一、应用中热点开启和关闭的代码：
- 二、系统源码追踪
- - 1、ConnectivityManager.startTethering
  - 2、TetheringManager.startTethering
  - 3、TetheringService.TetheringConnector.startTethering
  - 4、Tethering.startTethering(request, listener);
  - 5、WifiManager.startTetheredHotspot(null /* use existing softap config */)
  - 6、WifiServiceImpl.startTetheredHotspot(@Nullable SoftApConfiguration softApConfig)
  - 7、ActiveModeWarden.startSoftAp(apModeConfig);
  - 8、ActiveModeManager.start();
  - 10、WifiNative.startSoftAp
  - 11、HostapdHal.addAccessPoint
- 总结：
- - 1、流程总结：
  - 2、配置参数总结

本文对热点framework 中上层的代码逻辑进行梳理，供大家参考学习。

一、应用中热点开启和关闭的代码：

ConnectivityManager mConnectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);//开启mConnectivityManager.startTethering(ConnectivityManager.TETHERING_WIFI, true /* showProvisioningUi */,mOnStartTetheringCallback, new Handler(Looper.getMainLooper()));//关闭mConnectivityManager.stopTethering(ConnectivityManager.TETHERING_WIFI);

二、系统源码追踪

1、ConnectivityManager.startTethering

frameworks\base\core\java\android\net\ConnectivityManager.java

public static final int TETHERING_WIFI      = TetheringManager.TETHERING_WIFI;public static final int TETHERING_USB       = TetheringManager.TETHERING_USB;public static final int TETHERING_BLUETOOTH = TetheringManager.TETHERING_BLUETOOTH;private final TetheringManager mTetheringManager;public void startTethering(int type, boolean showProvisioningUi,final OnStartTetheringCallback callback, Handler handler) {Preconditions.checkNotNull(callback, "OnStartTetheringCallback cannot be null.");final Executor executor = new Executor() {@Overridepublic void execute(Runnable command) {if (handler == null) {command.run();} else {handler.post(command);}}};final StartTetheringCallback tetheringCallback = new StartTetheringCallback() {@Overridepublic void onTetheringStarted() {callback.onTetheringStarted();}@Overridepublic void onTetheringFailed(final int error) {callback.onTetheringFailed();}};final TetheringRequest request = new TetheringRequest.Builder(type).setShouldShowEntitlementUi(showProvisioningUi).build();//追踪：在mTetheringManager 中 startTetheringmTetheringManager.startTethering(request, executor, tetheringCallback);}

2、TetheringManager.startTethering

frameworks\base\packages\Tethering\common\TetheringLib\src\android\net\TetheringManager.java

@RequiresPermission(anyOf = {android.Manifest.permission.TETHER_PRIVILEGED,android.Manifest.permission.WRITE_SETTINGS})public void startTethering(@NonNull final TetheringRequest request,@NonNull final Executor executor, @NonNull final StartTetheringCallback callback) {final String callerPkg = mContext.getOpPackageName();Log.i(TAG, "startTethering caller:" + callerPkg);final IIntResultListener listener = new IIntResultListener.Stub() {@Overridepublic void onResult(final int resultCode) {executor.execute(() -> {if (resultCode == TETHER_ERROR_NO_ERROR) {callback.onTetheringStarted();} else {callback.onTetheringFailed(resultCode);}});}};//追踪：getConnector(c -> c.startTethering(request.getParcel(), callerPkg, listener));}private void getConnector(ConnectorConsumer consumer) {final ITetheringConnector connector;synchronized (mConnectorWaitQueue) {connector = mConnector;if (connector == null) {mConnectorWaitQueue.add(consumer);return;}}try {consumer.onConnectorAvailable(connector);} catch (RemoteException e) {throw new IllegalStateException(e);}}private interface ConnectorConsumer {void onConnectorAvailable(ITetheringConnector connector) throws RemoteException;}

从上面看是 ConnectorConsumer 的回调对象调用了 startTethering 方法

查哪个应用实现了 ITetheringConnector：

3、TetheringService.TetheringConnector.startTethering

frameworks\base\packages\Tethering\src\com\android\networkstack\tethering\TetheringService.java

TetheringService.TetheringConnector.startTethering

//内部接口类private static class TetheringConnector extends ITetheringConnector.Stub {private final TetheringService mService;private final Tethering mTethering;TetheringConnector(Tethering tether, TetheringService service) {mTethering = tether;mService = service;}@Overridepublic void tether(String iface, String callerPkg, IIntResultListener listener) {if (checkAndNotifyCommonError(callerPkg, listener)) return;try {listener.onResult(mTethering.tether(iface));} catch (RemoteException e) { }}@Overridepublic void startTethering(TetheringRequestParcel request, String callerPkg,IIntResultListener listener) {if (checkAndNotifyCommonError(callerPkg,request.exemptFromEntitlementCheck /* onlyAllowPrivileged */,listener)) {return;}//追踪：Tethering.startTetheringmTethering.startTethering(request, listener);}@Overridepublic void stopTethering(int type, String callerPkg, IIntResultListener listener) {if (checkAndNotifyCommonError(callerPkg, listener)) return;try {mTethering.stopTethering(type);listener.onResult(TETHER_ERROR_NO_ERROR);} catch (RemoteException e) { }}}

继续追踪Tethering 的 startTethering 方法

4、Tethering.startTethering(request, listener);

frameworks\base\packages\Tethering\src\com\android\networkstack\tethering\Tethering.java

void startTethering(final TetheringRequestParcel request, final IIntResultListener listener) {mHandler.post(() -> {final TetheringRequestParcel unfinishedRequest = mActiveTetheringRequests.get(request.tetheringType);// If tethering is already enabled with a different request,// disable before re-enabling.if (unfinishedRequest != null&& !TetheringUtils.isTetheringRequestEquals(unfinishedRequest, request)) {enableTetheringInternal(request.tetheringType, false /* disabled */, null);mEntitlementMgr.stopProvisioningIfNeeded(request.tetheringType);}mActiveTetheringRequests.put(request.tetheringType, request);if (request.exemptFromEntitlementCheck) {mEntitlementMgr.setExemptedDownstreamType(request.tetheringType);} else {mEntitlementMgr.startProvisioningIfNeeded(request.tetheringType,request.showProvisioningUi);}//追踪：enableTetheringInternal(request.tetheringType, true /* enabled */, listener);});}private void enableTetheringInternal(int type, boolean enable,final IIntResultListener listener) {int result = TETHER_ERROR_NO_ERROR;switch (type) {case TETHERING_WIFI://追踪：result = setWifiTethering(enable);break;
。。。case TETHERING_ETHERNET:result = setEthernetTethering(enable);break;default:Log.w(TAG, "Invalid tether type.");result = TETHER_ERROR_UNKNOWN_TYPE;}// The result of Bluetooth tethering will be sent by #setBluetoothTethering.if (type != TETHERING_BLUETOOTH) {sendTetherResult(listener, result, type);}}private int setWifiTethering(final boolean enable) {final long ident = Binder.clearCallingIdentity();try {synchronized (mPublicSync) {final WifiManager mgr = getWifiManager(); //最终还是调用了 wifiManagerif (mgr == null) {mLog.e("setWifiTethering: failed to get WifiManager!");return TETHER_ERROR_SERVICE_UNAVAIL;}//追踪：if ((enable && mgr.startTetheredHotspot(null /* use existing softap config */))|| (!enable && mgr.stopSoftAp())) {mWifiTetherRequested = enable;return TETHER_ERROR_NO_ERROR;}}} finally {Binder.restoreCallingIdentity(ident);}return TETHER_ERROR_INTERNAL_ERROR;}

5、WifiManager.startTetheredHotspot(null /* use existing softap config */)

frameworks\base\wifi\java\android\net\wifi\WifiManager.java

@SystemApi@RequiresPermission(anyOf = {android.Manifest.permission.NETWORK_STACK,NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK})public boolean startTetheredHotspot(@Nullable SoftApConfiguration softApConfig) {try {//追踪：return mService.startTetheredHotspot(softApConfig);} catch (RemoteException e) {throw e.rethrowFromSystemServer();}}

继续追一下WifiMananger在里面实现的

6、WifiServiceImpl.startTetheredHotspot(@Nullable SoftApConfiguration softApConfig)


//实现类
public class BaseWifiService extends IWifiManager.Stub { 。。。 }WifiServiceImpl.startTetheredHotspot(@Nullable SoftApConfiguration softApConfig) //更多实现的实现子类
/**
* WifiService handles remote WiFi operation requests by implementing
* the IWifiManager interface.
*/
public class WifiServiceImpl extends BaseWifiService {private final ActiveModeWarden mActiveModeWarden;@Overridepublic boolean startTetheredHotspot(@Nullable SoftApConfiguration softApConfig) {// NETWORK_STACK is a signature only permission.enforceNetworkStackPermission();mLog.info("startTetheredHotspot uid=%").c(Binder.getCallingUid()).flush();if (!mTetheredSoftApTracker.setEnablingIfAllowed()) {mLog.err("Tethering is already active.").flush();return false;}if (!mWifiThreadRunner.call(() -> mActiveModeWarden.canRequestMoreSoftApManagers(), false)) {// Take down LOHS if it is up.mLohsSoftApTracker.stopAll();}if (!startSoftApInternal(new SoftApModeConfiguration(WifiManager.IFACE_IP_MODE_TETHERED, softApConfig,mTetheredSoftApTracker.getSoftApCapability()))) {mTetheredSoftApTracker.setFailedWhileEnabling();return false;}return true;}private boolean startSoftApInternal(SoftApModeConfiguration apConfig) {int uid = Binder.getCallingUid();boolean privileged = isSettingsOrSuw(Binder.getCallingPid(), uid);mLog.trace("startSoftApInternal uid=% mode=%").c(uid).c(apConfig.getTargetMode()).flush();// null wifiConfig is a meaningful input for CMD_SET_AP; it means to use the persistent// AP config.SoftApConfiguration softApConfig = apConfig.getSoftApConfiguration();//存在 softApConfig 为 null的情况，所以不会进这里if (softApConfig != null&& (!WifiApConfigStore.validateApWifiConfiguration(softApConfig, privileged)|| !validateSoftApBand(softApConfig.getBand()))) {Log.e(TAG, "Invalid SoftApConfiguration");return false;}//追踪：mActiveModeWarden.startSoftAp(apConfig);return true;}}

值得注意的是上面的startSoftApInternal 方法中，
SoftApModeConfiguration apConfig 不为空，并且传入到后面的处理也不为空
只是SoftApConfiguration softApConfig = apConfig.getSoftApConfiguration();里面的softApConfig对象为null而已！

frameworks\opt\net\wifi\service\java\com\android\server\wifi\SoftApModeConfiguration.java

相当于一个普通的Bean类


class SoftApModeConfiguration {/*** Routing mode. Either {@link android.net.wifi.WifiManager#IFACE_IP_MODE_TETHERED}* or {@link android.net.wifi.WifiManager#IFACE_IP_MODE_LOCAL_ONLY}.*/private final int mTargetMode;private final SoftApCapability mCapability;/*** SoftApConfiguration for internal use, or null if it hasn't been generated yet.*/private final @Nullable SoftApConfiguration mSoftApConfig;SoftApModeConfiguration(int targetMode, @Nullable SoftApConfiguration config,SoftApCapability capability) {Preconditions.checkArgument(targetMode == WifiManager.IFACE_IP_MODE_TETHERED|| targetMode == WifiManager.IFACE_IP_MODE_LOCAL_ONLY);mTargetMode = targetMode;mSoftApConfig = config;mCapability = capability;}public int getTargetMode() {return mTargetMode;}public SoftApConfiguration getSoftApConfiguration() {return mSoftApConfig;}public SoftApCapability getCapability() {return mCapability;}
}

7、ActiveModeWarden.startSoftAp(apModeConfig);

frameworks\opt\net\wifi\service\java\com\android\server\wifi\ActiveModeWarden.java

private final WifiController mWifiController;private final WifiInjector mWifiInjector;/** Starts SoftAp. */public void startSoftAp(SoftApModeConfiguration softApConfig) {//追踪：CMD_SET_APmWifiController.sendMessage(WifiController.CMD_SET_AP, 1, 0, softApConfig);}/*** WifiController is the class used to manage wifi state for various operating* modes (normal, airplane, wifi hotspot, etc.).*/private class WifiController extends StateMachine {private static final String TAG = "WifiController";// Maximum limit to use for timeout delay if the value from overlay setting is too large.private static final int MAX_RECOVERY_TIMEOUT_DELAY_MS = 4000;private static final int BASE = Protocol.BASE_WIFI_CONTROLLER;static final int CMD_EMERGENCY_MODE_CHANGED                 = BASE + 1;static final int CMD_SCAN_ALWAYS_MODE_CHANGED               = BASE + 7;static final int CMD_WIFI_TOGGLED                           = BASE + 8;static final int CMD_AIRPLANE_TOGGLED                       = BASE + 9;static final int CMD_SET_AP                                 = BASE + 10;...static final int CMD_RECOVERY_DISABLE_WIFI                  = BASE + 19;static final int CMD_STA_STOPPED                            = BASE + 20;static final int CMD_DEFERRED_RECOVERY_RESTART_WIFI         = BASE + 22;static final int CMD_AP_START_FAILURE                       = BASE + 23;static final int CMD_UPDATE_AP_CAPABILITY                   = BASE + 24;static final int CMD_UPDATE_AP_CONFIG                       = BASE + 25;class EnabledState extends BaseState {@Overridepublic boolean processMessageFiltered(Message msg) {switch (msg.what) {。。。             //追踪：CMD_SET_APcase CMD_SET_AP:// note: CMD_SET_AP is handled/dropped in ECM mode - will not start hereif (msg.arg1 == 1) {//追踪：startSoftApModeManager((SoftApModeConfiguration) msg.obj);} else {stopSoftApModeManagers(msg.arg2);}break;case CMD_AP_STOPPED:case CMD_AP_START_FAILURE:
。。。default:return NOT_HANDLED;}return HANDLED;}}}private void startSoftApModeManager(@NonNull SoftApModeConfiguration softApConfig) {Log.d(TAG, "Starting SoftApModeManager config = "+ softApConfig.getSoftApConfiguration());Preconditions.checkState(softApConfig.getTargetMode() == IFACE_IP_MODE_LOCAL_ONLY|| softApConfig.getTargetMode() == IFACE_IP_MODE_TETHERED);WifiManager.SoftApCallback callback =softApConfig.getTargetMode() == IFACE_IP_MODE_LOCAL_ONLY? mLohsCallback : mSoftApCallback;SoftApListener listener = new SoftApListener();ActiveModeManager manager =mWifiInjector.makeSoftApManager(listener, callback, softApConfig);listener.setActiveModeManager(manager);manager.start();manager.setRole(getRoleForSoftApIpMode(softApConfig.getTargetMode()));mActiveModeManagers.add(manager);}

8、ActiveModeManager.start();

frameworks\opt\net\wifi\service\java\com\android\server\wifi\ActiveModeManager.java


public interface ActiveModeManager {/*** Listener for ActiveModeManager state changes.*/interface Listener {void onStarted();void onStopped();void onStartFailure();}void start();void stop();boolean isStopping();}

frameworks\opt\net\wifi\service\java\com\android\server\wifi\WifiInjector.java

public SoftApManager makeSoftApManager(@NonNull ActiveModeManager.Listener listener,@NonNull WifiManager.SoftApCallback callback,@NonNull SoftApModeConfiguration config) {return new SoftApManager(mContext, mWifiHandlerThread.getLooper(),mFrameworkFacade, mWifiNative, mCountryCode.getCountryCode(), listener, callback,mWifiApConfigStore, config, mWifiMetrics, mSarManager, mWifiDiagnostics);}

frameworks\opt\net\wifi\service\java\com\android\server\wifi\SoftApManager.java

SoftApManager 实现了 ActiveModeManager接口，
SoftApManager.startSoftAp()
里面包含了 SoftApStateMachine ，就是所谓的状态机对象

上面ActiveModeManager.start(); 就是调用到 SoftApManager.start()；最终调到 startSoftAp方法


/*** Manage WiFi in AP mode.* The internal state machine runs under the ClientModeImpl handler thread context.*/
public class SoftApManager implements ActiveModeManager {private static final String TAG = "SoftApManager";private final SoftApStateMachine mStateMachine;private final WifiApConfigStore mWifiApConfigStore;/*** Start soft AP, as configured in the constructor.*/@Overridepublic void start() { //追踪：CMD_STARTmStateMachine.sendMessage(SoftApStateMachine.CMD_START);}private class SoftApStateMachine extends StateMachine {// Commands for the state machine.public static final int CMD_START = 0;public static final int CMD_STOP = 1;
。。。public static final int CMD_UPDATE_CONFIG = 11;SoftApStateMachine(Looper looper) {super(TAG, looper);addState(mIdleState);addState(mStartedState);setInitialState(mIdleState);start();}private class IdleState extends State {@Overridepublic void enter() {mApInterfaceName = null;mIfaceIsUp = false;mIfaceIsDestroyed = false;}private class SoftApStateMachine extends StateMachine {// Commands for the state machine.public static final int CMD_START = 0;public static final int CMD_STOP = 1;
。。。public static final int CMD_UPDATE_CONFIG = 11;SoftApStateMachine(Looper looper) {super(TAG, looper);addState(mIdleState);addState(mStartedState);setInitialState(mIdleState);start();}private class IdleState extends State {@Overridepublic void enter() {mApInterfaceName = null;mIfaceIsUp = false;mIfaceIsDestroyed = false;}@Overridepublic boolean processMessage(Message message) {switch (message.what) {case CMD_STOP:mStateMachine.quitNow();break;//追踪：CMD_STARTcase CMD_START:mApInterfaceName = mWifiNative.setupInterfaceForSoftApMode(mWifiNativeInterfaceCallback);if (TextUtils.isEmpty(mApInterfaceName)) {Log.e(TAG, "setup failure when creating ap interface.");updateApState(WifiManager.WIFI_AP_STATE_FAILED,WifiManager.WIFI_AP_STATE_DISABLED,WifiManager.SAP_START_FAILURE_GENERAL);mWifiMetrics.incrementSoftApStartResult(false, WifiManager.SAP_START_FAILURE_GENERAL);mModeListener.onStartFailure();break;}mSoftApNotifier.dismissSoftApShutDownTimeoutExpiredNotification();updateApState(WifiManager.WIFI_AP_STATE_ENABLING,WifiManager.WIFI_AP_STATE_DISABLED, 0);//追踪：重点关注！int result = startSoftAp(); //关键流程if (result != SUCCESS) {int failureReason = WifiManager.SAP_START_FAILURE_GENERAL;if (result == ERROR_NO_CHANNEL) {failureReason = WifiManager.SAP_START_FAILURE_NO_CHANNEL;} else if (result == ERROR_UNSUPPORTED_CONFIGURATION) {failureReason = WifiManager.SAP_START_FAILURE_UNSUPPORTED_CONFIGURATION;}updateApState(WifiManager.WIFI_AP_STATE_FAILED,WifiManager.WIFI_AP_STATE_ENABLING,failureReason);stopSoftAp(); mWifiMetrics.incrementSoftApStartResult(false, failureReason);mModeListener.onStartFailure();break;}transitionTo(mStartedState);break;。。。default:// Ignore all other commands.break;}return HANDLED;}}//整个系统热点开启最重要的地方，通过这里日志能知道是否开启热点成功/*** Start a soft AP instance as configured.** @return integer result code*/private int startSoftAp() {SoftApConfiguration config = mApConfig.getSoftApConfiguration();//（1）判断配置对话和名称是否为nullif (config == null || config.getSsid() == null) {Log.e(TAG, "Unable to start soft AP without valid configuration");return ERROR_GENERIC;}Log.d(TAG, "band " + config.getBand() + " iface "+ mApInterfaceName + " country " + mCountryCode);//（2）判断是否能设置MAC地址int result = setMacAddress();if (result != SUCCESS) {return result;}//（3）判断是否能设置CountryCode，5G热点，band =2 的情况才要设置result = setCountryCode();if (result != SUCCESS) {return result;}//（4）重新创建一个热点配置对象，这个对象的数据才是传递给底层的！// Make a copy of configuration for updating AP band and channel.SoftApConfiguration.Builder localConfigBuilder = new SoftApConfiguration.Builder(config);boolean acsEnabled = mCurrentSoftApCapability.areFeaturesSupported(SoftApCapability.SOFTAP_FEATURE_ACS_OFFLOAD);//（5）重点来了！这里是有更新配置的逻辑result = ApConfigUtil.updateApChannelConfig(mWifiNative, mContext.getResources(), mCountryCode, localConfigBuilder, config,acsEnabled);if (result != SUCCESS) {Log.e(TAG, "Failed to update AP band and channel");return result;}if (config.isHiddenSsid()) {Log.d(TAG, "SoftAP is a hidden network");}//后面的都是一些基本检测和动作//（6）检测热点配置是否支持if (!ApConfigUtil.checkSupportAllConfiguration(config, mCurrentSoftApCapability)) {Log.d(TAG, "Unsupported Configuration detect! config = " + config);return ERROR_UNSUPPORTED_CONFIGURATION;}//（7）启动热点if (!mWifiNative.startSoftAp(mApInterfaceName,localConfigBuilder.build(), mSoftApListener)) {Log.e(TAG, "Soft AP start failed");return ERROR_GENERIC;}mWifiDiagnostics.startLogging(mApInterfaceName);mStartTimestamp = FORMATTER.format(new Date(System.currentTimeMillis()));//（8）热点启动成功的标志！Log.d(TAG, "Soft AP is started ");return SUCCESS;}}

10、WifiNative.startSoftAp

frameworks\opt\net\wifi\service\java\com\android\server\wifi\WifiNative.java

private final HostapdHal mHostapdHal;public boolean startSoftAp(@NonNull String ifaceName, SoftApConfiguration config, SoftApListener listener) {if (!mWifiCondManager.registerApCallback(ifaceName, Runnable::run, listener)) {Log.e(TAG, "Failed to register ap listener");return false;}if (!mHostapdHal.addAccessPoint(ifaceName, config, listener::onFailure)) {Log.e(TAG, "Failed to add acccess point");mWifiMetrics.incrementNumSetupSoftApInterfaceFailureDueToHostapd();return false;}return true;}

11、HostapdHal.addAccessPoint

frameworks\opt\net\wifi\service\java\com\android\server\wifi\HostapdHal.java

public boolean addAccessPoint(@NonNull String ifaceName, @NonNull SoftApConfiguration config,@NonNull Runnable onFailureListener) {synchronized (mLock) {int band;boolean enableAcs = ApConfigUtil.isAcsSupported(mContext) && config.getChannel() == 0&& !mForceApChannel;if (enableAcs) {ifaceParams.channelParams.enableAcs = true;ifaceParams.channelParams.acsShouldExcludeDfs = !mContext.getResources().getBoolean(R.bool.config_wifiSoftapAcsIncludeDfs);}//可以打印下channel 和 band 的值，查看传递给底层的具体数据ifaceParams.channelParams.channel =mForceApChannel ? mForcedApChannel : config.getChannel();band = mForceApChannel ? mForcedApBand : config.getBand();//添加传入到底层的数据：Log.i(TAG, "band = " + band + ", channel = "  + ifaceParams.channelParams.channel);android.hardware.wifi.hostapd.V1_2.IHostapd.NetworkParams nwParamsV1_2 =prepareNetworkParams(config);if (nwParamsV1_2 == null) return false;if (!checkHostapdAndLogFailure(methodStr)) return false;try {HostapdStatus status;if (!isV1_1() && !isV1_2()) {ifaceParams.channelParams.band = getHalBand(band);status = mIHostapd.addAccessPoint(ifaceParams, nwParamsV1_2.V1_0);if (!checkStatusAndLogFailure(status, methodStr)) {return false;}} else {android.hardware.wifi.hostapd.V1_1.IHostapd.IfaceParams ifaceParams1_1 =new android.hardware.wifi.hostapd.V1_1.IHostapd.IfaceParams();ifaceParams1_1.V1_0 = ifaceParams;if (!isV1_2()) {ifaceParams.channelParams.band = getHalBand(band);if (ifaceParams.channelParams.enableAcs) {if ((band & SoftApConfiguration.BAND_2GHZ) != 0) {ifaceParams1_1.channelParams.acsChannelRanges.addAll(toAcsChannelRanges(mContext.getResources().getString(R.string.config_wifiSoftap2gChannelList)));}if ((band & SoftApConfiguration.BAND_5GHZ) != 0) {ifaceParams1_1.channelParams.acsChannelRanges.addAll(toAcsChannelRanges(mContext.getResources().getString(R.string.config_wifiSoftap5gChannelList)));}}android.hardware.wifi.hostapd.V1_1.IHostapd iHostapdV1_1 =getHostapdMockableV1_1();if (iHostapdV1_1 == null) return false;status = iHostapdV1_1.addAccessPoint_1_1(ifaceParams1_1, nwParamsV1_2.V1_0);if (!checkStatusAndLogFailure(status, methodStr)) {return false;}ifaceParams.channelParams.channel =mForceApChannel ? mForcedApChannel : config.getChannel();band = mForceApChannel ? mForcedApBand : config.getBand();android.hardware.wifi.hostapd.V1_2.IHostapd.NetworkParams nwParamsV1_2 =prepareNetworkParams(config);} else {android.hardware.wifi.hostapd.V1_2.HostapdStatus status12;android.hardware.wifi.hostapd.V1_2.IHostapd.IfaceParams ifaceParams1_2 =new android.hardware.wifi.hostapd.V1_2.IHostapd.IfaceParams();ifaceParams1_2.V1_1 = ifaceParams1_1;ifaceParams1_2.hwModeParams.enable80211AX =mContext.getResources().getBoolean(R.bool.config_wifiSoftapIeee80211axSupported);ifaceParams1_2.hwModeParams.enable6GhzBand =mContext.getResources().getBoolean(R.bool.config_wifiSoftap6ghzSupported);ifaceParams1_2.hwModeParams.enableHeSingleUserBeamformer =mContext.getResources().getBoolean(R.bool.config_wifiSoftapHeSuBeamformerSupported);ifaceParams1_2.hwModeParams.enableHeSingleUserBeamformee =mContext.getResources().getBoolean(R.bool.config_wifiSoftapHeSuBeamformeeSupported);ifaceParams1_2.hwModeParams.enableHeMultiUserBeamformer =mContext.getResources().getBoolean(R.bool.config_wifiSoftapHeMuBeamformerSupported);ifaceParams1_2.hwModeParams.enableHeTargetWakeTime =mContext.getResources().getBoolean(R.bool.config_wifiSoftapHeTwtSupported);ifaceParams1_2.channelParams.bandMask = getHalBandMask(band);// Prepare freq ranges/lists if neededif (ifaceParams.channelParams.enableAcs&& isSendFreqRangesNeeded(band)) {if ((band & SoftApConfiguration.BAND_2GHZ) != 0) {ifaceParams1_2.channelParams.acsChannelFreqRangesMhz.addAll(toAcsFreqRanges(SoftApConfiguration.BAND_2GHZ));}if ((band & SoftApConfiguration.BAND_5GHZ) != 0) {ifaceParams1_2.channelParams.acsChannelFreqRangesMhz.addAll(toAcsFreqRanges(SoftApConfiguration.BAND_5GHZ));}if ((band & SoftApConfiguration.BAND_6GHZ) != 0) {ifaceParams1_2.channelParams.acsChannelFreqRangesMhz.addAll(toAcsFreqRanges(SoftApConfiguration.BAND_6GHZ));}}android.hardware.wifi.hostapd.V1_2.IHostapd iHostapdV1_2 =getHostapdMockableV1_2();if (iHostapdV1_2 == null) return false;status12 = iHostapdV1_2.addAccessPoint_1_2(ifaceParams1_2, nwParamsV1_2);if (!checkStatusAndLogFailure12(status12, methodStr)) {return false;}}}mSoftApFailureListeners.put(ifaceName, onFailureListener);return true;} catch (IllegalArgumentException e) {Log.e(TAG, "Unrecognized apBand: " + band);return false;} catch (RemoteException e) {handleRemoteException(e, methodStr);return false;}}}

总结：

1、流程总结：

(1)ConnectivityManager.startTethering
(2)TetheringManager.startTethering(request, executor, tetheringCallback)
(3)TetheringService.TetheringConnector.startTethering
(4)Tethering.startTethering(request, listener);
//方法名变化，使用null 对象开启热点
(5)WifiManager.startTetheredHotspot(null /* use existing softap config */)
(6)WifiServiceImpl.startTetheredHotspot(@Nullable SoftApConfiguration softApConfig)
//方法名再变化
(7)ActiveModeWarden.startSoftAp(apModeConfig);
(8)ActiveModeManager.start();ActiveModeManager manager = mWifiInjector.makeSoftApManager(listener, callback, softApConfig);listener.setActiveModeManager(manager);manager.start();
ActiveModeManager是接口类，会调用到SoftApManager.start()
(9)SoftApManager.startSoftAp()
(10)WifiNative.startSoftAp(mApInterfaceName, localConfigBuilder.build(), mSoftApListener)
(11)HostapdHal.addAccessPoint(ifaceName, config, listener::onFailure)
(12)根据硬件版本调用不同的接口实现:addAccessPoint_X_X

2、配置参数总结

热点的配置在SoftApManager.startSoftAp() 会有一定的修改，
比如channel ==0 的情况是会在ApConfigUtil.java中，对应的band范围内随机生成一个channel值。
frameworks\opt\net\wifi\service\java\com\android\server\wifi\util\ApConfigUtil.java

所以热点配置有变化，需要分析的生活，可以在SoftApManager 和相关文件中多添加日志即可。