[alsa-devel] [PATCH v4 16/20] ASoC: SOF: Add PCI device support

[Andy Shevchenko]

On Thu, Mar 28, 2019 at 02:21:47PM -0400, Pierre-Louis Bossart wrote:
> > > > +#if IS_ENABLED(CONFIG_SND_SOC_SOF_EDISON)
> > > 
> > > Can we use Merrifield / mrfld instead of EDISON in entire series?
> 
> we could, but I don't know of any other platform than Edison to run the
> code. I know it's less accurate from an architecture perspective but felt
> Merrifield was confusing for non-Intel folks.

We use Merrifield across the entire kernel. It would be confusing other way around.
So, please, change it to be consistent with the rest of the kernel.

> > And one more question, is there any howto to run a nocodec variant of SOF on
> > Intel Merrifield platform?
> 
> I haven't had time to look into this with the slew of comments on v3/v4 and
> travel. If you have a working Edison setup with 5.0+, then this should work
> as is. 

Where to get SOF binary, and more interesting where to get sources and howto
compile them into binary?

> the main issue is going to describe the SSP2 pins with ACPI ASL stuff
> to make sure they are in 3.3V and the right pinmux, that's the part that I
> keep kicking down the road. When I used Edison with the official built there
> was a 'simple' script for the pin-mux, if you have the moral equivalent in
> ASL I am all ears

I don't know what should be done and where, the pins themselves are in correct
mode set by firmware (if no-one touches them as GPIOs):

pin 75 (GP40_I2S_2_CLK) mode 1 0x00003221
pin 76 (GP41_I2S_2_FS) mode 1 0x00003221
pin 77 (GP42_I2S_2_RXD) mode 1 0x00003221
pin 78 (GP43_I2S_2_TXD) mode 1 0x00003221

If you talking about Edison/Arduino board and its discrete pin control, we have
a mechanism to set it from ASL.

-- 
With Best Regards,
Andy Shevchenko