[PATCH 08/25] serial: sh-sci: Make unsigned values in sci_baud_calc_hscif() unsigned

Geert Uytterhoeven
2015-11-19T18:39:30Z

Move the -1 offset of br to the assignment to *brr, so br cannot become
negative anymore, and update the clamp() call. Now all unsigned values
in sci_baud_calc_hscif() can become unsigned.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/tty/serial/sh-sci.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 9442961a198378c7..fba1e1eea15dc3a1 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -1870,7 +1870,8 @@ static unsigned int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq, int *brr,
unsigned int *srr, unsigned int *cks)
{
- int sr, c, br, err, recv_margin;
+ unsigned int sr, br, c;
+ int err, recv_margin;
int min_err = 1000; /* 100% */
int recv_max_margin = 0;

@@ -1880,9 +1881,9 @@ static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq, int *brr,
for (c = 0; c <= 3; c++) {
/* integerized formulas from HSCIF documentation */
br = DIV_ROUND_CLOSEST(freq, (sr *
- (1 << (2 * c + 1)) * bps)) - 1;
- br = clamp(br, 0, 255);
- err = DIV_ROUND_CLOSEST(freq, ((br + 1) * bps * sr *
+ (1 << (2 * c + 1)) * bps));
+ br = clamp(br, 1U, 256U);
+ err = DIV_ROUND_CLOSEST(freq, (br * bps * sr *
(1 << (2 * c + 1)) / 1000)) -
1000;
/* Calc recv margin
@@ -1908,7 +1909,7 @@ static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq, int *brr,
else
continue;

- *brr = br;
+ *brr = br - 1;
*srr = sr - 1;
*cks = c;
}
--
1.9.1