Almost all S/PDIF transmitters/receivers use SNDRV_PCM_FORMAT_S16.
(Some use S32 for 24-bit samples, but this doesn't matter for
IEC 60958/61937.)
This is only for some early revisions of the CMI8738 chip which require
software to generate the preamble/channel status/subcode/parity bits
for each subframe.
Regards,
Clemens
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