On 1/5/16 7:15 AM, Mark Brown wrote:
On Mon, Jan 04, 2016 at 05:20:25PM -0600, Pierre-Louis Bossart wrote:
Add card with dummy codec and DAI to make I2S signals observable.
Uses Mic and Speaker pins/widgets to control DAPM
I'm wondering how this is going to get loaded (I don't see what creates
the platform device) and how we handle systems with a CODEC connected on
the expansion headers?
Good question.
On the minnowmax we can't use the default firmware since users may use
different codecs and the pins may be used for different non-audio
functions and lures. The firmare team also didn't want to maintain tons
of options. Generating the image from source is possible but it requires
a fair amount of work to keep track of unrelated non-audio firmware updates.
To solve this audio is disabled by default, and we have an EFI
application loaded by the startup.nsh file that sets the relevant codec
information in the SSDT table so that you can swap codec cards at will.
The EFI application will be open-sourced so that additional codecs can
be added as needed with changes in the ASL code. The whole thing was
tested with experimental releases in three different setups for now but
will be formally released next month.
On probe the sst_acpi part checks for the presence of known codecs and
registers the platform driver. For the case where no codec is present I
just added an entry at the end of the table that always works (checks
for an SOC-side HID) and is selected if no other codec was found. I need
to add this patch and submit it, forgot to add it in this batch.
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