sample_size field in snd_dec_flac structure

In snd_dec_flac (see: https://github.com/torvalds/linux/blob/master/include/uapi/sound/compress_pa... ), there is the sample_size field.

It seems to me that this is meant to contain the same value as the sample size as the one in the frame header: https://xiph.org/flac/format.html#frame_header

Does this mean that if I always send a full FLAC stream into the device, with its complete STREAMINFO header, I can just always set sample_size to 0? The spec does mention that 0 mean "get [the sample size] from STREAMINFO metadata block".