I2S_CLKDIV_RXM_SHIFT
#define I2S_CLKDIV_RXM(x) (((x) - 1) << I2S_CLKDIV_RXM_SHIFT)
#define I2S_CLKDIV_RXM_MASK (0xff << I2S_CLKDIV_RXM_SHIFT)