diff --git a/include/uapi/linux/mmc/ioctl.h b/include/uapi/linux/mmc/ioctl.h
index 7e385b83b9d8..700a55156eee 100644
--- a/include/uapi/linux/mmc/ioctl.h
+++ b/include/uapi/linux/mmc/ioctl.h
@@ -69,6 +69,6 @@ struct mmc_ioc_multi_cmd {
  * is enforced per ioctl call.  For larger data transfers, use the normal
  * block device operations.
  */
-#define MMC_IOC_MAX_BYTES  (512L * 256)
+#define MMC_IOC_MAX_BYTES  (512L * 1024)
 #define MMC_IOC_MAX_CMDS    255
 #endif /* LINUX_MMC_IOCTL_H */