[alsa-devel] ASoC Sound Driver I2S over LPE, Intel Baytrail SoC. MinnowBoard Max

[Michael Pogrebinsky]

Hi Pierre,
I downloaded 4.3 stable kernel, and I applied all the commits in the repo
you forwarded to me.
I'm running into an issue, where after doing those instructions:
"iasl -tc dsdt_minnow.dsl

mv dsdt_minnow.hex include/

the options following options need to be set in the .config
for the tables to be taken into account:

CONFIG_ACPI_CUSTOM_DSDT_FILE=dsdt_minnow.hex
CONFIG_ACPI_CUSTOM_DSDT=y"

"
I am not able to boot the kernel.
The last message I see on the screen before it goes blank is the system is
trying to load rmfs.
If I take the kernel with your patches however, and do not set the
Config_ACPI_CUSTOM_DST_FILE to dsdt_minnow.hex and do not run the iasl
tool. ( I just take the kernel with the patches) the system loads.

On the same note I should mention that I am running on Atom E3825 64 bit.
Thanks,
Michael





On Tue, Nov 10, 2015 at 11:59 AM, Michael Pogrebinsky <
michael.pogrebinsky at daqri.com> wrote:

> Hi Pierre,
> Thank you so much for your reply, and for sharing your repo.
> This is great news for me, as I was blocked for a while on this issue. And
> I'm particularly happy that this is all done on top of the 4.3 Kernel, this
> is very professional of you. I will try the code, and definitely let you
> know how it goes, or if I have any issues.
>
> Thank you again,
> Michael
>
>
>
> On Tue, Nov 10, 2015 at 10:53 AM, Pierre-Louis Bossart <
> pierre-louis.bossart at linux.intel.com> wrote:
>
>> Hi Michael,
>>
>> I have the MinnowBoard Max with Baytrail Atom (ValleyView) SoC.
>>> I'm attempting to write an Alsa (ASoC) driver for my sound card to
>>> work with this board.
>>> PCM should work through I2S for this sound card I have.
>>>
>>
>> Good to hear. There are several folks in Intel trying to enable I2S over
>> the low-speed connector for 3rd party enablement or help 'makers'. This is
>> still work-in-progress but we can already share some elements of
>> information based on our own experience:
>> 1. the default 0.82 firmware doesn't enable the I2S pins, we are
>> currently using a DSDT override to configure them.
>> 2. the audio codec needs to be registered as a child of I2C6 (it's
>> typically I2C2 on regular baytrail platforms). this is also part of the
>> DSDT override.
>> 3. since we need to support multiple audio codecs, we'd like to add a
>> mechanism to add information in the SSDT table to be able to boot the same
>> kernel and select the right drivers. Alternatively you will have to use the
>> DSDT override method until this mechanism is ready.
>> 4. there is no MCLK on existing MinnowBoards, so your codec will have to
>> drive its PLL from the BLCK. newer versions of the MinnowBoard Turbot will
>> support an MCLK but they are in pre-production stage and to the best of my
>> knowledge not available commercially yet.
>> 5. to get the best long-term support you really want to use the newer
>> DPCM-based driver/firmware for e.g 24-bit, TDM and deep-buffer support. We
>> have a set of patches that have not been published upstream yet but if you
>> are interested you can look at my github
>> https://github.com/plbossart/sound/tree/minnow-v4.3-24bit. In theory if
>> you take this code and change the DSDT to support your _HID just like it
>> was done for the rt5651 the drivers should load and register a sound card.
>> Disclaimer: there is no official support on this branch and rebases/fixes
>> may happen at any time. the code will be submitted upstream when ready.
>>
>> If you provide more information on which codec you are trying to link to
>> we can help further.
>> -Pierre
>>
>
>
>
> --
>
> [image: DAQRI] <http://daqri.com/>
>
> Michael Pogrebinsky
>
> Senior Android Developer - DAQRI Smart Helmet Applications
>
> *Tel:* *844-327-7443*
>
> michael.pogrebinsky at daqri.com <stephen.keegan at daqri.com>
> DAQRI.com <http://daqri.com/>
>



-- 

[image: DAQRI] <http://daqri.com/>

Michael Pogrebinsky

Senior Android Developer - DAQRI Smart Helmet Applications

*Tel:* *844-327-7443*

michael.pogrebinsky at daqri.com <stephen.keegan at daqri.com>
DAQRI.com <http://daqri.com/>