On Friday 07 June 2019 18:03:50 Luiz Augusto von Dentz wrote: > Hi Pali, > > On Fri, Jun 7, 2019 at 4:43 PM Pali Rohár <pali.rohar@xxxxxxxxx> wrote: > > > > On Sunday 19 May 2019 12:18:54 Pali Rohár wrote: > > > Hello! > > > > > > Now I'm looking at BT_VOICE_TRANSPARENT definition which comes from file > > > include/net/bluetooth/bluetooth.h and it has value 0x0003. It is really > > > correct? Because it means following format: > > > > > > Linear Coding, 8-bit without padding bits, 1's complement > > > > > > I think that usage of 1's complement is not easy as there is no C type > > > which matches it. Should not it be 2's complement or rather Unsigned > > > type? > > > > > > Seems that main usage of BT_VOICE_TRANSPARENT is mSBC codec and I doubt > > > that it uses 1's complement signed format (specially as it should be > > > modification of SBC codec which encode bytes as unsigned type). > > > > > > There is another define BT_VOICE_CVSD_16BIT with value 0x0060 which > > > seems to be correct as it means Linear Coding, 16-bit without padding > > > bits, 2's complement and encoded by CVSD codec. > > > > Hello, can somebody look at this BT_VOICE_TRANSPARENT definition and > > verify that it really should be defined as unsigned or 2's complement? > > Are you talking about these: > > https://elixir.bootlin.com/linux/latest/source/include/net/bluetooth/bluetooth.h#L119 Yes, exactly. > Which is used in ofono: > > https://github.com/DynamicDevices/ofono/blob/master/src/handsfree-audio.c#L93 > > Afaik these values work as intended with mSBC/WBS. And I suspect that definition is wrong. mSBC does not use 1's complement format. -- Pali Rohár pali.rohar@xxxxxxxxx
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