[alsa-devel] Intel SST on a Bay Trail tablet

[Vinod Koul]

On Tue, Mar 03, 2015 at 04:54:53PM +0200, Jarkko Nikula wrote:
> Hi
> 
> On 03/03/2015 04:16 PM, Antonio Ospite wrote:
> >On Mon, 23 Feb 2015 18:39:13 +0100
> >Antonio Ospite <ao2 at ao2.it> wrote:
> >
> >>Hi,
> >>
> >>I am trying to get the Intel SST driver working on a Teclast X98 Air 3G
> >>[1], it's a Bay Trail tablet. The tests below have been made with
> >>4.0.0-rc1 and the firmware files from
> >>https://git.kernel.org/cgit/linux/kernel/git/firmware/linux-firmware.git/tree/intel
> >>
> >
> >Hi, has anyone had a chance to take a look at my previous message?
> >
> I forgot to answer... Some earlier notes including Teclast X98 Air
> 3G and patch attempts are collected here:
> 
> https://bugzilla.kernel.org/show_bug.cgi?id=86581
> 
> Unfortunately bug is not solved since it looks these newer Baytrail
> Windows 8.1 based machines use different SSP port than previous ones
> and Linux DSP firmware is hardcoded for SSP2.
> 
> What's interesting does that Android FW use other than SSP2 or does
> Teclast have some extra amplifier.
> 
> >[...]
> >>Last question, what is the difference between having the device detected
> >>by sound/soc/intel/sst-acpi.c (like in my case) opposed to
> >>sound/soc/intel/sst/sst_acpi.c? I can see the 80860F28 id in both the
> >>files but they seem to load different firmwares.
> >>
> 
> Different firmware, driver stack and machine driver despite the same
> LPE ACPI ID and codec ACPI ID. (We really should have some
> additional DMI quirks that does the selection because of the same
> ACPI IDs).
> 
> >
> >Another thing I noticed is that the Android driver for the rt5640 codec
> >defines some controls which are not in the mainline driver:
> >
> >   OUT MIXR BST3 Switch
> >   OUT MIXL BST3 Switch
> >   RECMIXR BST3 Switch
> >   RECMIXL BST3 Switch
> >   IN1 Mode Control
> >   IN2 Mode Control
> >
> I'm not sure but these might be FW implemented DSP controls? Vinod,
> do you know?

Nope these are not DSP based... From description Antonio is saying these are
from rt5640 driver... not upstreamed I think.

-- 
~Vinod

> 
> -- 
> Jarkko

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