Skip to content

Application_Notes_M2_WiFi_BT.rst

Latest commit

 

History

History
324 lines (214 loc) · 9.08 KB

Application_Notes_M2_WiFi_BT.rst

File metadata and controls

324 lines (214 loc) · 9.08 KB
Raw

M.2 Wi-Fi and Bluetooth module setup

This application note describes the Android build system modifications required to integrate third-party M.2 Wi-Fi and Bluetooth modules.

Warning

This guide assumes the kernel already includes the required drivers and device tree overlays. For kernel configuration, see :ref:`android-build-kernel`.

Introduction

The AM62Px-SK and AM62x-SK Evaluation Modules (EVMs) include an M.2 Key E connector that supports Wi-Fi and Bluetooth combo modules. These modules typically use:

  • Secure Digital Input/Output (SDIO) interface for Wi-Fi
  • Universal Asynchronous Receiver-Transmitter (UART) interface for Bluetooth

This guide lists the files you need to change in the Android build system to add support for a new Wi-Fi and Bluetooth module.

Wi-Fi firmware setup

Note

Depending on your Wi-Fi module, you might also need to change the Wi-Fi Hardware Abstraction Layer (HAL) configuration in :file:`device/ti/am62x/shared/wifi/`. The default configuration uses TI-specific libraries (lib_driver_cmd_ti). For other modules, you might need to update :file:`BoardConfig.mk` to use the appropriate driver library (e.g., lib_driver_cmd_nl80211 for generic NL80211 drivers).

Adding firmware files

Copy the firmware files to the appropriate directory:

$ cp <firmware_file> \
    ${YOUR_PATH}/ti-aosp-16/vendor/ti/am62x/wifi/vendor/firmware/<vendor_dir>/

Common vendor directories:

  • mrvl/ for Marvell (now NXP Semiconductors)
  • ti-connectivity/ for TI
  • brcm/ for Broadcom/Cypress
  • nxp/ for NXP Semiconductors Bluetooth firmware

Change Android.bp

Edit :file:`vendor/ti/am62x/wifi/Android.bp` and add a prebuilt_firmware module.

prebuilt_firmware {
    name: "<package_name>",
    vendor: true,
    src: "vendor/firmware/<vendor_dir>/<firmware_file>",
    filename: "<firmware_file>",
    sub_dir: "<vendor_dir>",
    proprietary: true,
}

Change the product Makefile

.. ifconfig:: CONFIG_part_variant in ('AM62PX')

   Edit :file:`vendor/ti/am62x/am62p.mk` and add the firmware to PRODUCT_PACKAGES.


.. ifconfig:: CONFIG_part_variant in ('AM62X')

   Edit :file:`vendor/ti/am62x/am62x.mk` and add the firmware to PRODUCT_PACKAGES.


PRODUCT_PACKAGES += \
    <package_name>

Bluetooth configuration

M.2 Wi-Fi and Bluetooth combo modules typically use UART for Bluetooth communication. Change the following files to enable Bluetooth.

Change device_vendor.mk

Edit :file:`device/ti/am62x/shared/bluetooth/device_vendor.mk` to enable Bluetooth permissions and HAL.

Change from disabled Bluetooth:

PRODUCT_COPY_FILES += \
    device/generic/car/common/android.hardware.disable.xml:$(TARGET_COPY_OUT_VENDOR)/etc/permissions/android.hardware.bluetooth.xml \
    device/generic/car/common/android.hardware.disable.xml:$(TARGET_COPY_OUT_VENDOR)/etc/permissions/android.hardware.bluetooth_le.xml

To enabled Bluetooth:

# Bluetooth configuration

# Enable Bluetooth permissions
PRODUCT_COPY_FILES += \
    frameworks/native/data/etc/android.hardware.bluetooth.xml:$(TARGET_COPY_OUT_VENDOR)/etc/permissions/android.hardware.bluetooth.xml \
    frameworks/native/data/etc/android.hardware.bluetooth_le.xml:$(TARGET_COPY_OUT_VENDOR)/etc/permissions/android.hardware.bluetooth_le.xml

# Bluetooth HAL (AIDL)
PRODUCT_PACKAGES += \
    android.hardware.bluetooth-service.default

Change product.prop

Edit :file:`device/ti/am62x/product.prop` and add Bluetooth properties.

Example configuration (adjust profiles based on your module capabilities):

# Bluetooth configuration
# Set the Bluetooth Class of Device
# Service Field: 0x5A -> 90
#    Bit 17: Networking
#    Bit 19: Capturing
#    Bit 20: Object Transfer
#    Bit 22: Telephony
# MAJOR_CLASS: 0x01 -> 1 (Computer)
# MINOR_CLASS: 0x04 -> 4 (Desktop workstation)
bluetooth.device.class_of_device=90,1,4

# Set supported Bluetooth profiles to enabled
bluetooth.profile.asha.central.enabled?=true
bluetooth.profile.a2dp.source.enabled?=true
bluetooth.profile.avrcp.target.enabled?=true
bluetooth.profile.gatt.enabled?=true
bluetooth.profile.hfp.ag.enabled?=true
bluetooth.profile.hid.device.enabled?=true
bluetooth.profile.hid.host.enabled?=true
bluetooth.profile.map.server.enabled?=true
bluetooth.profile.opp.enabled?=true
bluetooth.profile.pan.nap.enabled?=true
bluetooth.profile.pan.panu.enabled?=true
bluetooth.profile.pbap.server.enabled?=true

# Disable LeAudio profiles (requires specific hardware support)
bluetooth.profile.bap.broadcast.assist.enabled=false
bluetooth.profile.bap.unicast.client.enabled=false
bluetooth.profile.bas.client.enabled=false
bluetooth.profile.ccp.server.enabled=false
bluetooth.profile.csip.set_coordinator.enabled=false
bluetooth.profile.hap.client.enabled=false
bluetooth.profile.vcp.controller.enabled=false

Note

The bluetooth.profile.*.enabled?=true syntax (with ?) enables the profile by default but allows overriding. Profiles disabled with =false (without ?) cannot be overridden.

Change ueventd.rc

.. ifconfig:: CONFIG_part_variant in ('AM62PX')

   Edit :file:`device/ti/am62x/am62p/ueventd.am62p.rc` and add UART permissions:


.. ifconfig:: CONFIG_part_variant in ('AM62X')

   Edit :file:`device/ti/am62x/am62x/ueventd.am62x.rc` and add UART permissions:


# Bluetooth UART
/dev/ttyS1    0660   bluetooth  bluetooth

Note

The UART device name (ttyS1, ttyS2, and so on) depends on your device tree overlay configuration.

Change file_contexts

Edit :file:`device/ti/am62x/sepolicy/common/file_contexts` and add:

# Bluetooth UART
/dev/ttyS1                      u:object_r:hci_attach_dev:s0

Adding SELinux policy

Create :file:`device/ti/am62x/sepolicy/common/hal_bluetooth_default.te`:

# Allow Bluetooth HAL to access UART device
allow hal_bluetooth_default hci_attach_dev:chr_file rw_file_perms;

Build and flash

Rebuild the Android image

$ cd ${YOUR_PATH}/ti-aosp-16
$ source build/envsetup.sh
$ lunch <BUILD_TARGET>
$ m

Flash the device

After building, flash the device again following the standard flashing procedure documented in :ref:`android-flashing`.

Configure the device tree blob overlay (DTBO)

After flashing, configure the DTBO index from U-Boot:

=> env set adtbo_idx <your_dtbo_index>
=> saveenv
=> reset

See :ref:`android-dtbo` for the list of available DTBO overlays and their indices.

Summary

Change the following files to add Wi-Fi and Bluetooth support:

.. ifconfig:: CONFIG_part_variant in ('AM62PX')

   .. list-table::
      :header-rows: 1
      :widths: 50 50

      * - File
        - Purpose

      * - :file:`vendor/ti/am62x/wifi/Android.bp`
        - Add prebuilt_firmware module for Wi-Fi/BT firmware

      * - :file:`vendor/ti/am62x/am62p.mk`
        - Add firmware to PRODUCT_PACKAGES

      * - :file:`device/ti/am62x/shared/bluetooth/device_vendor.mk`
        - Enable Bluetooth permissions XML and HAL

      * - :file:`device/ti/am62x/product.prop`
        - Add Bluetooth properties (class of device, profiles)

      * - :file:`device/ti/am62x/am62p/ueventd.am62p.rc`
        - Set UART device permissions for Bluetooth

      * - :file:`device/ti/am62x/sepolicy/common/file_contexts`
        - Add SELinux context for Bluetooth UART

      * - :file:`device/ti/am62x/sepolicy/common/hal_bluetooth_default.te`
        - Add SELinux policy for Bluetooth HAL UART access


.. ifconfig:: CONFIG_part_variant in ('AM62X')

   .. list-table::
      :header-rows: 1
      :widths: 50 50

      * - File
        - Purpose

      * - :file:`vendor/ti/am62x/wifi/Android.bp`
        - Add prebuilt_firmware module for Wi-Fi/BT firmware

      * - :file:`vendor/ti/am62x/am62x.mk`
        - Add firmware to PRODUCT_PACKAGES

      * - :file:`device/ti/am62x/shared/bluetooth/device_vendor.mk`
        - Enable Bluetooth permissions XML and HAL

      * - :file:`device/ti/am62x/product.prop`
        - Add Bluetooth properties (class of device, profiles)

      * - :file:`device/ti/am62x/am62x/ueventd.am62x.rc`
        - Set UART device permissions for Bluetooth

      * - :file:`device/ti/am62x/sepolicy/common/file_contexts`
        - Add SELinux context for Bluetooth UART

      * - :file:`device/ti/am62x/sepolicy/common/hal_bluetooth_default.te`
        - Add SELinux policy for Bluetooth HAL UART access