diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c
index dce4a7e69b46..523f2f649e26 100644
--- a/drivers/spi/spi-altera.c
+++ b/drivers/spi/spi-altera.c
@@ -134,7 +134,7 @@ static int altera_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
 	hw->tx = t->tx_buf;
 	hw->rx = t->rx_buf;
 	hw->count = 0;
-	hw->bytes_per_word = t->bits_per_word / 8;
+	hw->bytes_per_word = DIV_ROUND_UP(t->bits_per_word, 8);
 	hw->len = t->len / hw->bytes_per_word;
 
 	if (hw->irq >= 0) {