diff --git a/drivers/mmc/mxsmmc.c b/drivers/mmc/mxsmmc.c
index 35c6bdabb06d4b71e8cf46263aa22c2cbf0301ec..6572e9551bafd827edcc0fcb02dbf6904bfb3f21 100644
--- a/drivers/mmc/mxsmmc.c
+++ b/drivers/mmc/mxsmmc.c
@@ -406,7 +406,7 @@ int mxsmmc_initialize(bd_t *bis, int id, int (*wp)(int))
 	 */
 	mmc->f_min = 400000;
 	mmc->f_max = mxc_get_clock(MXC_SSP0_CLK + id) * 1000 / 2;
-	mmc->b_max = 0x40;
+	mmc->b_max = 0x20;
 
 	mmc_register(mmc);
 	return 0;