According to i.MX 6 Linux reference manual 32.2 SPDIF Tx driver, support 32, 44.1 and 48 KHz sample rate. Is it possible to set output sample rate below 32k?
According to fsl_spdif.c linux-2.6-imx.git - Freescale i.MX Linux Tree , the sample_rate range is 32k to 192k.