MMC_REG_RES_FIFO
a = mxcmci_readw(host, MMC_REG_RES_FIFO);
b = mxcmci_readw(host, MMC_REG_RES_FIFO);
a = mxcmci_readw(host, MMC_REG_RES_FIFO);
b = mxcmci_readw(host, MMC_REG_RES_FIFO);
c = mxcmci_readw(host, MMC_REG_RES_FIFO);