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Date:   Tue, 22 Dec 2020 14:20:49 +0100
From:   Pali =?utf-8?B?Um9ow6Fy?= <pali@kernel.org>
To:     Pasi =?utf-8?B?S8Okcmtrw6RpbmVu?= <pasik@iki.fi>
Cc:     Joakim Tjernlund <Joakim.Tjernlund@infinera.com>,
        "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>
Subject: Re: Default to HW mSBC on capable controllers ?
Message-ID: <20201222132049.de24v7rarpuf7hoh@pali>
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On Tuesday 22 December 2020 12:49:40 Pali Rohár wrote:
> On Tuesday 22 December 2020 13:40:24 Pasi Kärkkäinen wrote:
> > Hello Pali,
> > 
> > On Mon, Dec 21, 2020 at 10:07:07PM +0100, Pali Rohár wrote:
> > > 
> > > > Any idea if one could patch the kernel to default to HW mSBC and user apps like bluealsa/pulseaudio would just use it automatically?
> > > 
> > > For usage mSBC hw encoder you need to use Enhanced Setup Synchronous
> > > Connection HCI command for establishing SCO connection.
> > > 
> > > For using HW encoder you need to stop feeding socket with mSBC encoded
> > > data and instead put into this socket RAW pcm samples. Also you need
> > > somehow inform kernel about this change.
> > > 
> > > For both things I designed new setsockopt() API which I described in:
> > > https://lore.kernel.org/linux-bluetooth/20200419234937.4zozkqgpt557m3o6@pali/
> > >
> > 
> > In that thread Luiz asked for changes to the patch, eg. kernel module option is needed which allows enabling new/experimental features, and your changes should be enabled only when experimental option is given while loading the module.
> > 
> > See here:
> > https://lore.kernel.org/linux-bluetooth/CABBYNZJTBM87Yr+rqUm6MwwSR60YNe+UFr0HHj5T2DkY7LqJqA@mail.gmail.com/
> > 
> > Could you please add that kernel module option, and re-send the patch ? 

Pasi, I understood that Marcel is against it. But if bluetooth
maintainers approve this API, I may try to implement it. If API must be
hidden under compile time CONFIG_* kernel option it is also possible.
Just I need to know exact answer "yes" or "no".

> I have not implemented it. I just proposed API between userspace and
> kernel. But I have not implemented this API yet.