Re: [PATCHv4 04/12] android/handsfree: Add SCO Audio IPC

[Szymon Janc <szymon.janc@tieto.com>]

Hi Andrei,

On Friday 09 of May 2014 11:07:05 Andrei Emeltchenko wrote:
> Hi Szymon,
> 
> On Fri, May 09, 2014 at 10:02:11AM +0200, Szymon Janc wrote:
> > Hi,
> > 
> > On Friday 09 of May 2014 10:37:27 Andrei Emeltchenko wrote:
> > > Hi Luiz,
> > > 
> > > On Thu, May 08, 2014 at 04:22:35PM +0300, Luiz Augusto von Dentz wrote:
> > > > >  static bool connect_sco(void)
> > > > > @@ -904,7 +930,7 @@ static bool connect_sco(void)
> > > > >                                 device.negotiated_codec != CODEC_ID_CVSD)
> > > > >                 voice_settings = BT_VOICE_TRANSPARENT;
> > > > >         else
> > > > > -               voice_settings = BT_VOICE_CVSD_16BIT;
> > > > > +               voice_settings = 0;
> > > > 
> > > > What is the reason for changing this value to 0?
> > > 
> > > Otherwise we always call setsockopt which fails in old kernels.
> > > 
> > > in sco_set():
> > > 	if (!voice)
> > > 		return TRUE;
> > > 
> > > 	bt_voice.setting = voice;
> > > 	if (setsockopt(sock, SOL_BLUETOOTH, BT_VOICE, &bt_voice,
> > > 						sizeof(bt_voice)) < 0) {
> > > 		ERROR_FAILED(err, "setsockopt(BT_VOICE)", errno);
> > > 		return FALSE;
> > > 	}
> > 
> > Mgmt 1.3 is already required by Android bluetoothd (kernel 3.9+) and most
> > likely this dependency will be bumped to 1.4 or 1.5. So I wouldn't worry much
> > about older kernels.
> 
> The reason I add this patch was not because I specially like old kernels
> but because this is real use case. What is the default kernel for Android
> 4.4?

KitKat for Nexus 4/7 have kernel 3.4 but we use backports since bluetooth
subsystem must be from 3.9+ kernel.

-- 
Best regards, 
Szymon Janc