diff --git a/sys/dev/mmc/host/dwmmc.c b/sys/dev/mmc/host/dwmmc.c
--- a/sys/dev/mmc/host/dwmmc.c
+++ b/sys/dev/mmc/host/dwmmc.c
@@ -1358,7 +1358,7 @@
 		*(int *)result = sc->host.caps;
 		break;
 	case MMCBR_IVAR_MAX_DATA:
-		*(int *)result = (IDMAC_MAX_SIZE * IDMAC_DESC_SEGS) / MMC_SECTOR_SIZE;
+		*(int *)result = IDMAC_DESC_SEGS;
 		break;
 	case MMCBR_IVAR_TIMING:
 		*(int *)result = sc->host.ios.timing;