serial: 8250_dw: Pass the same rate to the clk round and set rate methods

Indeed according to the clk API if clk_round_rate() has successfully
accepted a rate, then in order setup the clock with value returned by the
clk_round_rate() the clk_set_rate() method must be called with the
original rate value.

Suggested-by: Russell King <linux@armlinux.org.uk>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 12866083731d45b110824c3e92408f11297f78e5..c1511f9244bb4f01662631129476c2ffa91366b3 100644 (file)
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -275,15 +275,15 @@ dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
 static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
                               struct ktermios *old)
 {
-       unsigned int baud = tty_termios_baud_rate(termios);
+       unsigned long newrate = tty_termios_baud_rate(termios) * 16;
        struct dw8250_data *d = to_dw8250_data(p->private_data);
        long rate;
        int ret;
 
        clk_disable_unprepare(d->clk);
-       rate = clk_round_rate(d->clk, baud * 16);
+       rate = clk_round_rate(d->clk, newrate);
        if (rate > 0) {
-               ret = clk_set_rate(d->clk, rate);
+               ret = clk_set_rate(d->clk, newrate);
                if (!ret)
                        p->uartclk = rate;
        }