[alsa-devel] [PATCH v4 0/9] adapt SOF to use snd-hda-codec-hdmi

[Pierre-Louis Bossart]

On 9/17/19 6:32 AM, Kai Vehmanen wrote:
> Hi,
> 
> On Mon, 16 Sep 2019, Pierre-Louis Bossart wrote:
> 
>> The series looks good to me so
>> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
> 
> thank you Pierre and Takashi for the reviews!
> 
>> I would recommend that we have a matching change for the Skylake driver and
>> validation that both SOF and cAVS/SST drivers can operate with this mode set.
>> Our goal is still to have coexistence between the two drivers in a single
>> build/distro, e.g. cAVS for SKL/KBL/APL and SOF for newer platforms. This can
>> be done in a follow-up patch but it needs to be done before distros start
>> selecting this common HDMI mode.
> 
> The current patchset actually does allow that. You can select the common
> HDMI codec in kernel config, build both SOF and SST drivers and based on
> runtime selection of the platform, either SOF with patch_hdmi.c will be
> used or SST with hdac-hdmi. This is achieved by setting the
> common-hdmi-codec mach-params flag in sof/intel/hda.c, so with SST
> drivers, this will never be set.
> 
> To change SST to use patch_hdmi.c as well, is a bigger effort. There
> are more (and much older) platforms impacted by the alsa mixer name
> changes. I'm not sure whether this is worth the trouble. But open to
> ideas here.

If the i915 interface was set in stone yes we could probably leave the 
Skylake driver alone. But there are changes from time to time and bug 
fixes that will require Intel to work on two parts of the tree, so 
really wondering if we shouldn't just move to this common mode across 
the board and remove hdac_hdmi.c. it doesn't need to be done at once but 
it's not that crazy to aim for the next kernel release.