ASoC: codecs: Add HD-Audio codec driver
Add generic ASoC equivalent of ALSA HD-Audio codec. This codec is designed to follow HDA_DEV_LEGACY convention. Driver wrapps existing hda_codec.c handlers to prevent code duplication within the newly added code. Number of DAIs created is dependent on capabilities exposed by the codec itself. Because of this, single solution can be applied to support every single HD-Audio codec type. At the same time, through the ASoC topology, platform drivers may limit the number of endpoints available to the userspace as codec driver exposes BE DAIs only. Both hda_codec_probe() and hda_codec_remove() declare their expectations on device's usage_count and suspended-status. This is to catch any unexpected behavior as PM-related code for HD-Audio has been changing quite a bit throughout the years. In order for codec DAI list to reflect its actual PCM capabilities, PCMs need to be built and that can only happen once codec device is constructed. To do that, a valid component->card->snd_card pointer is needed. Said pointer will be provided by the framework once all card components are accounted for and their probing can begin. Usage of "binder" BE DAI solves the problem - codec can be listed as one of HD-Audio card components without declaring any actual BE DAIs statically. Relation with hdac_hda: Addition of parallel solution is motivated by behavioral differences between hdac_hda.c and its legacy equivalent found in sound/pci/hda e.g.: lack of dynamic, based on codec capabilities, resource allocation and high cost of removing such differences on actively used targets. Major goal of codec driver presented here is to follow HD-Audio legacy behavior in 1:1 fashion by becoming a wrapper. Doing so increases code coverage of the legacy code and reduces the maintenance cost for both solutions. Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com> Link: https://lore.kernel.org/r/20220511162403.3987658-3-cezary.rojewski@intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
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