BlueZ port to Android version 4.4.2

BlueZ port to Android version 4.4.2

[Marc Anders]

Hello,

I am trying to port BlueZ to an Android 4.4.2 kernel.  I followed the
instructions I found on the following site:
https://git.kernel.org/cgit/bluetooth/bluez.git/tree/android/README

I have the project compiling and was able to flash to the board.  When
the bluetooth system boots up however the Bluez system times out
during its init with the following error logs:

05-26 09:05:36.381 D/BlueZ   ( 1828):
external/bluetooth/bluez/android/hal-bluetooth.c:open_bluetooth()
05-26 09:05:36.381 D/BlueZ   ( 1828):
external/bluetooth/bluez/android/hal-bluetooth.c:get_bluetooth_interface()
05-26 09:05:36.401 D/BlueZ   ( 1828):
external/bluetooth/bluez/android/hal-bluetooth.c:init()
05-26 09:05:36.551 I/bluetoothd( 1893): Bluetooth daemon 5.39
05-26 09:05:36.551 I/bluetoothd( 1893): Starting SDP server
05-26 09:05:36.551 I/bluetoothd( 1893): Bluetooth management interface
1.3 initialized
05-26 09:05:41.541 I/bluetoothd( 1893): Stopping SDP server
05-26 09:05:41.541 I/bluetoothd( 1893): Exit
05-26 09:05:46.431 E/BlueZ   ( 1828): bluetoothd connect timeout

Looking further into what is causing the bluetoothd to time out I've
found that calling poll() within the accept_connection() function
within hal-bluetooth.c is what causes this.  Using the process
described in the above readme I did port over the new epoll_create1()
and ppoll() calls from
https://github.com/bluez-android/aosp_platform_bionic.  I'm trying to
determine what the poll() function is calling out to that is causing
this to timeout.

Any assistance is appreciated,

Thank you.

Re: BlueZ port to Android version 4.4.2

[Szymon Janc]

Hi Mark,

On Monday 30 May 2016 19:42:06 Marc Anders wrote:
> Hello,
> 
> I am trying to port BlueZ to an Android 4.4.2 kernel.  I followed the
> instructions I found on the following site:
> https://git.kernel.org/cgit/bluetooth/bluez.git/tree/android/README
> 
> I have the project compiling and was able to flash to the board.  When
> the bluetooth system boots up however the Bluez system times out
> during its init with the following error logs:
> 
> 05-26 09:05:36.381 D/BlueZ   ( 1828):
> external/bluetooth/bluez/android/hal-bluetooth.c:open_bluetooth()
> 05-26 09:05:36.381 D/BlueZ   ( 1828):
> external/bluetooth/bluez/android/hal-bluetooth.c:get_bluetooth_interface()
> 05-26 09:05:36.401 D/BlueZ   ( 1828):
> external/bluetooth/bluez/android/hal-bluetooth.c:init()
> 05-26 09:05:36.551 I/bluetoothd( 1893): Bluetooth daemon 5.39
> 05-26 09:05:36.551 I/bluetoothd( 1893): Starting SDP server
> 05-26 09:05:36.551 I/bluetoothd( 1893): Bluetooth management interface
> 1.3 initialized
> 05-26 09:05:41.541 I/bluetoothd( 1893): Stopping SDP server
> 05-26 09:05:41.541 I/bluetoothd( 1893): Exit
> 05-26 09:05:46.431 E/BlueZ   ( 1828): bluetoothd connect timeout
> 
> Looking further into what is causing the bluetoothd to time out I've
> found that calling poll() within the accept_connection() function
> within hal-bluetooth.c is what causes this.  Using the process
> described in the above readme I did port over the new epoll_create1()
> and ppoll() calls from
> https://github.com/bluez-android/aosp_platform_bionic.  I'm trying to
> determine what the poll() function is calling out to that is causing
> this to timeout.
> 
> Any assistance is appreciated,

bluetoothd from BlueZ for Android requires BT adapter to be ready before it is 
started. Typically on Android device this done by hciattach or brcm_patchram.

To do this automatically I suggest to have hciattach service that is started 
is bluetoothd service is started. This should be enough since bluetoothd wait  
5 seconds before shutting down. You can check at https://github.com/bluez-android how this was done for Nexus devices.

ie.

on property:init.svc.bluetoothd=running
    start hciattach

on property:init.svc.bluetoothd=stopped
    stop hciattach


-- 
pozdrawiam
Szymon Janc