Isolated SPI on DRV8301-RM48-KIT doesn't work

I can't seem to make the SPI communication work on DRV8301-RM48-KIT. I use HALCoGen to generate the necessary libraries for SPI1, debug using Code Composer Studio v5.3, but I cant send or receive any data, and I also cant see any clock pulses on the iCLK-O pin of J8 (other pins are also constantly high without any pulses, so I'm not sure if the isolated SPI on the board works at all). I need to send 32 bits of code to a device (2x16 bits consecutively I guess) and receive the same amount of data afterwards. Here's what my code looks like:

spiDAT1_t g_dataconfig_t;
    g_dataconfig_t.CS_HOLD = 1;
    g_dataconfig_t.WDEL = 0;
    g_dataconfig_t.DFSEL = SPI_FMT_0;
    g_dataconfig_t.CSNR = 0;

    spiInit();
    spiTransmitData(spiREG1, &g_dataconfig_t, 2, source);
    spiReceiveData(spiREG1, &g_dataconfig_t, 2, dest);