SDIO_CCCR_SPEED
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
ret = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
ret = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_SPEED, 0, &speed);
err = mmc_io_rw_direct(card, 1, 0, SDIO_CCCR_SPEED, speed, NULL);
err = rsi_cmd52readbyte(card, SDIO_CCCR_SPEED, &cmd52_resp);
SDIO_CCCR_SPEED,