The io controller interface specification was written before we became aware of this app note:
http://www.sharpsma.com/p...xxx_StaticMemory.pdf

since then we have added a barrier function between each access to the spi interface in the cpld in order to make sure that the chip select line
toggles.

code snippet:
void
barrier(void)
{
/* flash is guaranteed not to be cached, and to be in
* a different region from the cpld */
volatile u_int tmp = *(volatile u_int *)MEMAP_BASE_FLASH;
tmp = 1;
}

code snippet:

barrier();

/* load spi data into shift register */
REG16(dev->data_reg) = src[i];

barrier();

/* write out the command */
REG16(dev->control_reg) =
(CPLD_CE_SPI_CNTL_LOAD_REG | dev->chip_select);

barrier();

The next version of the io spec will include the updated information.
An errata to the current io spec should be posted shortly.

sorry for any inconvience this caused. i think it will solve your problems.

for reference, here are the codec configuration commands we are using to test the codec:
/* touch_codec measurement commands */
/* line off, 'x' 1, 'x' 1, dac on, out on, osc on, clk on, 'off' on, 'x' 0 */
static const u_int16_t PWR_ON = 0x0c07; /* power down control 0x0110*/
/* FOR 0x10: I2S format, MSB first, left -1 aligned, */
/* IWL 0x00: input bit length 16 bits, */
/* LRP 0x0 : right channel on, LRCIN high, LRSWAP 0x0: disabled, */
/* MS 0x1 : Master */
static const u_int16_t IF_FMT_CONF = 0x0e42;/* dig audio intfc format 0x0111 */
static const u_int16_t IF_ON = 0x1201;/* dig intfc activation 0x1001 - ON */
/* all da path control bits set to 0 for no muting and de-emphasis control*/
static const u_int16_t DACM_DIS = 0x0a00;/* dig audio path cntrl 0x0101 */