[PATCH v3 1/3] serial: sh-sci: Avoid divide-by-zero fault

[Biju <biju.das.au@gmail.com>]

From: Biju Das <biju.das.jz@bp.renesas.com>

The expression (10000 * bits) / (baud / 100) can produce a divide-by-zero
if baud is less than 100, since integer division yields zero before the
outer divide occurs. Rewrite it as (10000 * bits) * 100 / baud, which is
algebraically equivalent but eliminates the intermediate division, making
a zero divisor impossible for any valid baud rate.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v3:
 * New patch.
---
 drivers/tty/serial/sh-sci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 6c819b6b2425..7473b26ce9cf 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2915,7 +2915,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
 	}
 
 	/* Calculate delay for 2 DMA buffers (4 FIFO). */
-	s->rx_frame = (10000 * bits) / (baud / 100);
+	s->rx_frame = (10000 * bits) * 100 / baud;
 #ifdef CONFIG_SERIAL_SH_SCI_DMA
 	s->rx_timeout = s->buf_len_rx * 2 * s->rx_frame;
 #endif
-- 
2.43.0