Android bluetooth 模块架构

android bluetooth系统自上而下包含了 驱动程序和协议，Bluez库，Bluetooth的android适配库，java中的bluetooth类等几部分：

1. 内核层：
蓝牙系统的内核部分，有两个层次，分别是蓝牙的驱动程序和蓝牙的协议层。

2. Bluez库：
代码路径：/external/bluetooth/*
生成libbluetooth.so, bluetoothd, 及hcidump等众多工具和库。

I checked the Bluetooth subsystem in our baseline code.

 

1. I found that maybe we didn't have WL1271 BT  driver. There is only a CONFIG_BT_WL1271 in omap3_adlink_android_defconfig.  

 

CONFIG_BT_WL1271 is only used in /drivers/tty/tty_io.c to control the power of BT_EN. Here I corrected the OMAP3_EVEM_BT_PWR_GPIO from 136 to 65.

 

2.  And I have configed BT protocols as follow:

 

CONFIG_BT=y
CONFIG_BT_L2CAP=y
CONFIG_BT_SCO=y
CONFIG_BT_RFCOMM=y
CONFIG_BT_RFCOMM_TTY=y
CONFIG_BT_BNEP=y
CONFIG_BT_BNEP_MC_FILTER=y
CONFIG_BT_BNEP_PROTO_FILTER=y
CONFIG_BT_HIDP=y

#
# Bluetooth device drivers
#
# CONFIG_BT_HCIBTUSB is not set
# CONFIG_BT_HCIBTSDIO is not set
CONFIG_BT_HCIUART=y
CONFIG_BT_HCIUART_H4=y
# CONFIG_BT_HCIUART_BCSP is not set
# CONFIG_BT_HCIUART_ATH3K is not set
CONFIG_BT_HCIUART_LL=y
# CONFIG_BT_HCIBCM203X is not set
# CONFIG_BT_HCIBPA10X is not set
# CONFIG_BT_HCIBFUSB is not set
# CONFIG_BT_HCIVHCI is not set
# CONFIG_BT_MRVL is not set
CONFIG_BT_WL1271=y
# CONFIG_AF_RXRPC is not set     

 

3. In hardware/ti/wlan/WL1271_COMPAT,  it only installed the firmwares and wl1271bt_enable . I think TIInit_7.2.31.bts is the firmware for BT. But I don't know how it loaded. And I don't sure whether it is loaded or not when open bluetooth in Setting.

 

    @# Installing WLAN/BT firmwares and tools to rootfs..
    @echo "Installing WLAN/BT firmwares and tools to rootfs.."
    @install ../firmwares/TIInit_7.2.31.bts                    $(DESTDIR)/system/lib/firmware/
    @install ../firmwares/ti-connectivity/wl1271-fw-2.bin      $(DESTDIR)/system/etc/firmware/ti-connectivity/
    @install ../firmwares/ti-connectivity/wl1271-nvs.bin       $(DESTDIR)/system/etc/firmware/ti-connectivity/
    @install ../tools/wl1271bt_enable                          $(DESTDIR)/root/

 

4. In root/init.rc,  the services are running well:

 

service dbus /system/bin/dbus-daemon --system --nofork
    socket dbus stream 660 bluetooth bluetooth
    user bluetooth
    group bluetooth net_bt_admin

 

service bluetoothd /system/bin/bluetoothd -n
    socket bluetooth stream 660 bluetooth bluetooth
    socket dbus_bluetooth stream 660 bluetooth bluetooth

 

# init.rc does not yet support applying capabilities, so run as root and
# let bluetoothd drop uid to bluetooth with the right linux capabilities
    group bluetooth net_bt_admin misc
    disabled

 

service hfag /system/bin/sdptool add --channel=10 HFAG
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

 

service hsag /system/bin/sdptool add --channel=11 HSAG
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

 

service opush /system/bin/sdptool add --channel=12 OPUSH
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

 

service pbap /system/bin/sdptool add --channel=19 PBAP
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

# rfkill is not supported, use this instead                             
service btpwr /wl1271bt_enable /dev/ttyO1               // here it seems using btpwr to replace rfkill.
    disabled
    oneshot

 

service hciattach /system/bin/hciattach -n /dev/ttyO1 texas 3000000
    user root

 

# changing user to root from bluetooth is a potential security issue
    group bluetooth net_bt_admin misc
    disabled
    oneshot

 

5. When I open the bluetooth in Setting, it reports logs as follow:

 

D/BluetoothService( 1221): Bluetooth state 10 -> 11
V/BluetoothEventRedirector( 1595): Received android.bluetooth.adapter.action.STATE_CHANGED
D/bluedroid( 1221): bt_enable
D/bluedroid( 1221): defined OMAP3EVM_BTPWR
[   62.133941] Set BT_EN of WL1271
[   62.137207] WL1271: Powering on
I/bluedroid( 1221): Starting hciattach daemon                                
E/bluedroid( 1221): bt_enable: Timeout waiting for HCI device to come up
D/BluetoothService( 1221): Bluetooth state 11 -> 10
V/BluetoothEventRedirector( 1595): Received android.bluetooth.adapter.action.STATE_CHANGED
D/dalvikvm( 1459): GC_EXPLICIT freed 495K, 52% free 2783K/5703K, external 716K/1038K, paused 24ms