en/devices/bluetooth/index.html - platform/docs/source.android.com - Git at Google

 <html devsite>
   <head>
     <title>Bluetooth</title>
     <meta name="project_path" value="/_project.yaml" />
     <meta name="book_path" value="/_book.yaml" />
   </head>
   <body>
     <!--
       Copyright 2017 The Android Open Source Project

       Licensed under the Apache License, Version 2.0 (the "License"); you may
       not use this file except in compliance with the License.  You may obtain a
       copy of the License at

           http://www.apache.org/licenses/LICENSE-2.0

       Unless required by applicable law or agreed to in writing, software
       distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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       under the License.
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     <figure>
     <img style="float: right; margin: 0px 15px 15px 15px;"
     src="/devices/bluetooth/images/ape_fwk_hal_bluetooth.png"
     alt="Android Bluetooth HAL icon"/>
     </figure>

     <p>
     Android provides a default Bluetooth stack that supports both Classic
     Bluetooth and Bluetooth Low Energy. Using Bluetooth, Android devices can
     create personal area networks to send and receive data with nearby Bluetooth
     devices.
     </p>

     <p>
     In Android 4.3 and later, the Android Bluetooth stack provides the ability to
     implement Bluetooth Low Energy (BLE). To fully leverage the BLE APIs, follow
     the <a
       href="/devices/bluetooth/hci_requirements.html">Android
       Bluetooth HCI Requirements</a>. Android devices with a qualified chipset
     can implement either Classic Bluetooth or both Classic Bluetooth and BLE.
     BLE is not backwards compatible with older Bluetooth chipsets.
     </p>

     <p>
     In Android 8.0, the native Bluetooth stack is fully qualified for Bluetooth
     5. To use available Bluetooth 5 features, the device needs to have a
     Bluetooth 5 qualified chipset.
     </p>

     <aside class="note"><strong>Note</strong>: The largest change in the native
     Bluetooth stack between Android 8.0 and previous versions is the use of
     <a href="/devices/architecture/treble.html">Treble</a>. Vendor
     implementations in Android 8.0 must use HIDL instead of
     <code>libbt-vendor</code>.</aside>

     <h2 id="architecture-android-80">Android 8.0 architecture</h2>

       <p>
       A Bluetooth application communicates with the Bluetooth process through
       Binder. The Bluetooth process uses JNI to communicate with the Bluetooth
       stack and provides developers with access to various Bluetooth profiles.
       This diagram shows the general structure of the Bluetooth stack:
       </p>

       <figure id="figure1">
       <img src="/devices/bluetooth/images/fluoride_architecture.png"
       alt="Android 8.0 Bluetooth architecture"/>
       <figcaption>
       <strong>Figure 1.</strong> Android 8.0 Bluetooth architecture
       </figcaption>
       </figure>

       <dl>
         <dt>Application framework</dt>
         <dd>
         At the application framework level is application code, which uses the
         <a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
         android.bluetooth</a> APIs to interact with the Bluetooth hardware.
         Internally, this code calls the Bluetooth process through the Binder
         IPC mechanism.
         </dd>

         <dt>Bluetooth system service</dt>
         <dd>
         The Bluetooth system service, located in <code>packages/apps/Bluetooth</code>,
         is packaged as an Android app and implements the Bluetooth services
         and profiles at the Android framework layer. This app calls into the
         native Bluetooth stack via JNI.
         </dd>

         <dt>JNI</dt>
         <dd>
         The JNI code associated with android.bluetooth is located in
         <code>packages/apps/Bluetooth/jni</code>. The JNI code calls into the
         Bluetooth stack when certain Bluetooth operations occur, such as when
         devices are discovered.
         </dd>

         <dt>Bluetooth stack</dt>
         <dd>
         The default Bluetooth stack is provided in AOSP and is located in
         <code>system/bt</code>. The stack implements the generic Bluetooth HAL
         and customizes it with extensions and configuration changes.
         </dd>

         <dt>Vendor implementation</dt>
         <dd>
         Vendor devices interact with the Bluetooth stack using the Hardware
         Interface Design Language (HIDL).
         </dd>
       </dl>

       <h3 id="hidl">HIDL</h3>
       <p>
       <a href="/devices/architecture/hidl.html">HIDL</a> defines the interface
       between the Bluetooth stack and the vendor implementation. To generate the
       Bluetooth HIDL files, pass the Bluetooth interface files into the HIDL
       generation tool. The interface files are located in
       <a href="https://android.googlesource.com/platform/hardware/interfaces/+/master/bluetooth/"
       class="external"><code>hardware/interfaces/bluetooth</code></a>.
       </p>

       <h3 id="bluetooth-stack-development">Bluetooth stack development</h3>
       <p>
       The Android 8.0 Bluetooth stack is a fully qualified Bluetooth stack. The
       qualification listing is on the Bluetooth SIG website under <a
         href="https://www.bluetooth.org/tpg/QLI_viewQDL.cfm?qid=35890">QDID 97584</a>.
       </p>

       <p>
       The core Bluetooth stack resides in
       <code><a
           href="https://android.googlesource.com/platform/system/bt/+/master">
           system/bt</a></code>.
       Development happens in AOSP, and contributions are welcome.
       </p>

     <h2 id="architecture-android-7x-and-earlier">Android 7.x and earlier
       architecture</h2>
       <p>A Bluetooth system service communicates with the Bluetooth stack
       through JNI and with applications through Binder IPC. The system service
       provides developers with access to various Bluetooth profiles. This
       diagram shows the general structure of the Bluetooth stack:
       </p>

       <figure id="figure2">
       <img src="/devices/bluetooth/images/ape_fwk_bluetooth.png"
       alt="Android Bluetooth architecture" />
       <figcaption>
       <strong>Figure 2.</strong> Android 7.x and earlier Bluetooth architecture
       </figcaption>
       </figure>

       <dl>
         <dt>Application framework</dt>
         <dd>At the application framework level is application code, which
          utilizes the <a
          href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
          android.bluetooth</a> APIs to interact with the Bluetooth hardware.
          Internally, this code calls the Bluetooth process through the Binder
          IPC mechanism.
         </dd>

         <dt>Bluetooth system service</dt>
         <dd>The Bluetooth system service, located in
         <code>packages/apps/Bluetooth</code>, is packaged as an Android app and
         implements the Bluetooth service and profiles at the Android framework
         layer. This app calls into the HAL layer via JNI.
         </dd>

         <dt>JNI</dt>
         <dd>The JNI code associated with <a
           href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
           android.bluetooth</a> is located in
         <code>packages/apps/Bluetooth/jni</code>. The JNI code calls into the
         HAL layer and receives callbacks from the HAL when certain Bluetooth
         operations occur, such as when devices are discovered.
         </dd>

         <dt>HAL</dt>
         <dd>The hardware abstraction layer defines the standard interface that
           the <a
             href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
             android.bluetooth</a> APIs and Bluetooth process call into and that
           you must implement to have your Bluetooth hardware function correctly.
           The header file for the Bluetooth HAL is
           <code>hardware/libhardware/include/hardware/bluetooth.h</code>.
           Additionally, review all of the
           <code>hardware/libhardware/include/hardware/bt_*.h</code> files.
         </dd>

         <dt>Bluetooth stack</dt>
         <dd>The default Bluetooth stack is provided for you and is located in
         <code>system/bt</code>. The stack implements the generic Bluetooth HAL
         and customizes it with extensions and configuration changes.
         </dd>

         <dt>Vendor extensions</dt>
         <dd>To add custom extensions and an HCI layer for tracing, you can
         create a libbt-vendor module and specify these components.
         </dd>

       </dl>

       <h3 id="implementing-the-hal">Implementing the HAL</h3>
         <p>The Bluetooth HAL is located in
         <code>/hardware/libhardware/include/hardware/bluetooth.h</code>.
         The <code>bluetooth.h</code> file contains the basic interface for the
         Bluetooth stack, and you must implement its functions.</p>

         <p>Profile-specific files are located in the same directory. For
         details, see the <a href="/reference/hal/dir_6b11132f1a015b03f2670f21bef1d871.html">
         HAL File Reference</a>.
         </p>

   </body>
 </html>
	<html devsite>
	<head>
	<title>Bluetooth</title>
	<meta name="project_path" value="/_project.yaml" />
	<meta name="book_path" value="/_book.yaml" />
	</head>
	<body>
	<!--
	Copyright 2017 The Android Open Source Project

	Licensed under the Apache License, Version 2.0 (the "License"); you may
	not use this file except in compliance with the License. You may obtain a
	copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
	WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
	License for the specific language governing permissions and limitations
	under the License.
	-->
	<figure>
	<img style="float: right; margin: 0px 15px 15px 15px;"
	src="/devices/bluetooth/images/ape_fwk_hal_bluetooth.png"
	alt="Android Bluetooth HAL icon"/>
	</figure>

	<p>
	Android provides a default Bluetooth stack that supports both Classic
	Bluetooth and Bluetooth Low Energy. Using Bluetooth, Android devices can
	create personal area networks to send and receive data with nearby Bluetooth
	devices.
	</p>

	<p>
	In Android 4.3 and later, the Android Bluetooth stack provides the ability to
	implement Bluetooth Low Energy (BLE). To fully leverage the BLE APIs, follow
	the <a
	href="/devices/bluetooth/hci_requirements.html">Android
	Bluetooth HCI Requirements</a>. Android devices with a qualified chipset
	can implement either Classic Bluetooth or both Classic Bluetooth and BLE.
	BLE is not backwards compatible with older Bluetooth chipsets.
	</p>

	<p>
	In Android 8.0, the native Bluetooth stack is fully qualified for Bluetooth
	5. To use available Bluetooth 5 features, the device needs to have a
	Bluetooth 5 qualified chipset.
	</p>

	<aside class="note"><strong>Note</strong>: The largest change in the native
	Bluetooth stack between Android 8.0 and previous versions is the use of
	<a href="/devices/architecture/treble.html">Treble</a>. Vendor
	implementations in Android 8.0 must use HIDL instead of
	<code>libbt-vendor</code>.</aside>

	<h2 id="architecture-android-80">Android 8.0 architecture</h2>

	<p>
	A Bluetooth application communicates with the Bluetooth process through
	Binder. The Bluetooth process uses JNI to communicate with the Bluetooth
	stack and provides developers with access to various Bluetooth profiles.
	This diagram shows the general structure of the Bluetooth stack:
	</p>

	<figure id="figure1">
	<img src="/devices/bluetooth/images/fluoride_architecture.png"
	alt="Android 8.0 Bluetooth architecture"/>
	<figcaption>
	<strong>Figure 1.</strong> Android 8.0 Bluetooth architecture
	</figcaption>
	</figure>

	<dl>
	<dt>Application framework</dt>
	<dd>
	At the application framework level is application code, which uses the
	<a href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
	android.bluetooth</a> APIs to interact with the Bluetooth hardware.
	Internally, this code calls the Bluetooth process through the Binder
	IPC mechanism.
	</dd>

	<dt>Bluetooth system service</dt>
	<dd>
	The Bluetooth system service, located in <code>packages/apps/Bluetooth</code>,
	is packaged as an Android app and implements the Bluetooth services
	and profiles at the Android framework layer. This app calls into the
	native Bluetooth stack via JNI.
	</dd>

	<dt>JNI</dt>
	<dd>
	The JNI code associated with android.bluetooth is located in
	<code>packages/apps/Bluetooth/jni</code>. The JNI code calls into the
	Bluetooth stack when certain Bluetooth operations occur, such as when
	devices are discovered.
	</dd>

	<dt>Bluetooth stack</dt>
	<dd>
	The default Bluetooth stack is provided in AOSP and is located in
	<code>system/bt</code>. The stack implements the generic Bluetooth HAL
	and customizes it with extensions and configuration changes.
	</dd>

	<dt>Vendor implementation</dt>
	<dd>
	Vendor devices interact with the Bluetooth stack using the Hardware
	Interface Design Language (HIDL).
	</dd>
	</dl>

	<h3 id="hidl">HIDL</h3>
	<p>
	<a href="/devices/architecture/hidl.html">HIDL</a> defines the interface
	between the Bluetooth stack and the vendor implementation. To generate the
	Bluetooth HIDL files, pass the Bluetooth interface files into the HIDL
	generation tool. The interface files are located in
	<a href="https://android.googlesource.com/platform/hardware/interfaces/+/master/bluetooth/"
	class="external"><code>hardware/interfaces/bluetooth</code></a>.
	</p>

	<h3 id="bluetooth-stack-development">Bluetooth stack development</h3>
	<p>
	The Android 8.0 Bluetooth stack is a fully qualified Bluetooth stack. The
	qualification listing is on the Bluetooth SIG website under <a
	href="https://www.bluetooth.org/tpg/QLI_viewQDL.cfm?qid=35890">QDID 97584</a>.
	</p>

	<p>
	The core Bluetooth stack resides in
	<code><a
	href="https://android.googlesource.com/platform/system/bt/+/master">
	system/bt</a></code>.
	Development happens in AOSP, and contributions are welcome.
	</p>

	<h2 id="architecture-android-7x-and-earlier">Android 7.x and earlier
	architecture</h2>
	<p>A Bluetooth system service communicates with the Bluetooth stack
	through JNI and with applications through Binder IPC. The system service
	provides developers with access to various Bluetooth profiles. This
	diagram shows the general structure of the Bluetooth stack:
	</p>

	<figure id="figure2">
	<img src="/devices/bluetooth/images/ape_fwk_bluetooth.png"
	alt="Android Bluetooth architecture" />
	<figcaption>
	<strong>Figure 2.</strong> Android 7.x and earlier Bluetooth architecture
	</figcaption>
	</figure>

	<dl>
	<dt>Application framework</dt>
	<dd>At the application framework level is application code, which
	utilizes the <a
	href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
	android.bluetooth</a> APIs to interact with the Bluetooth hardware.
	Internally, this code calls the Bluetooth process through the Binder
	IPC mechanism.
	</dd>

	<dt>Bluetooth system service</dt>
	<dd>The Bluetooth system service, located in
	<code>packages/apps/Bluetooth</code>, is packaged as an Android app and
	implements the Bluetooth service and profiles at the Android framework
	layer. This app calls into the HAL layer via JNI.
	</dd>

	<dt>JNI</dt>
	<dd>The JNI code associated with <a
	href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
	android.bluetooth</a> is located in
	<code>packages/apps/Bluetooth/jni</code>. The JNI code calls into the
	HAL layer and receives callbacks from the HAL when certain Bluetooth
	operations occur, such as when devices are discovered.
	</dd>

	<dt>HAL</dt>
	<dd>The hardware abstraction layer defines the standard interface that
	the <a
	href="http://developer.android.com/reference/android/bluetooth/package-summary.html">
	android.bluetooth</a> APIs and Bluetooth process call into and that
	you must implement to have your Bluetooth hardware function correctly.
	The header file for the Bluetooth HAL is
	<code>hardware/libhardware/include/hardware/bluetooth.h</code>.
	Additionally, review all of the
	<code>hardware/libhardware/include/hardware/bt_*.h</code> files.
	</dd>

	<dt>Bluetooth stack</dt>
	<dd>The default Bluetooth stack is provided for you and is located in
	<code>system/bt</code>. The stack implements the generic Bluetooth HAL
	and customizes it with extensions and configuration changes.
	</dd>

	<dt>Vendor extensions</dt>
	<dd>To add custom extensions and an HCI layer for tracing, you can
	create a libbt-vendor module and specify these components.
	</dd>

	</dl>

	<h3 id="implementing-the-hal">Implementing the HAL</h3>
	<p>The Bluetooth HAL is located in
	<code>/hardware/libhardware/include/hardware/bluetooth.h</code>.
	The <code>bluetooth.h</code> file contains the basic interface for the
	Bluetooth stack, and you must implement its functions.</p>

	<p>Profile-specific files are located in the same directory. For
	details, see the <a href="/reference/hal/dir_6b11132f1a015b03f2670f21bef1d871.html">
	HAL File Reference</a>.
	</p>

	</body>
	</html>