diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index e40e1c01de..294d9f9d79 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -405,7 +405,7 @@ int spi_flash_cmd_write_ops(struct spi_flash *flash, u32 offset,
 
 		if (spi->max_write_size)
 			chunk_len = min(chunk_len,
-					(size_t)spi->max_write_size);
+					spi->max_write_size - sizeof(cmd));
 
 		spi_flash_addr(write_addr, cmd);
 
diff --git a/include/spi.h b/include/spi.h
index 4787454e59..5a7df1c706 100644
--- a/include/spi.h
+++ b/include/spi.h
@@ -89,7 +89,7 @@ struct dm_spi_slave_platdata {
  * @max_read_size:	If non-zero, the maximum number of bytes which can
  *			be read at once.
  * @max_write_size:	If non-zero, the maximum number of bytes which can
- *			be written at once, excluding command bytes.
+ *			be written at once.
  * @memory_map:		Address of read-only SPI flash access.
  * @flags:		Indication of SPI flags.
  */