1 files changed, 5 insertions, 5 deletions

diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
index 4e9f4f29f3ce..8b2d7356611d 100644
--- a/drivers/tty/serial/st-asc.c
+++ b/drivers/tty/serial/st-asc.c
@@ -527,12 +527,12 @@ static void asc_set_termios(struct uart_port *port, struct ktermios *termios,
                  * ASCBaudRate =   ------------------------
                  *                          inputclock
                  *
-                 * However to keep the maths inside 32bits we divide top and
-                 * bottom by 64. The +1 is to avoid a divide by zero if the
-                 * input clock rate is something unexpected.
+                 * To keep maths inside 64bits, we divide inputclock by 16.
                  */
-                u32 counter = (baud * 16384) / ((port->uartclk / 64) + 1);
-                asc_out(port, ASC_BAUDRATE, counter);
+                u64 dividend = (u64)baud * (1 << 16);
+
+                do_div(dividend, port->uartclk / 16);
+                asc_out(port, ASC_BAUDRATE, dividend);
                 ctrl_val |= ASC_CTL_BAUDMODE;
         }