lkml.org 
[lkml]   [2021]   [Nov]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH V3] pwm: rcar: Use div64_ul instead of do_div
Date
From: Changcheng Deng <deng.changcheng@zte.com.cn>

do_div() does a 64-by-32 division. Here the divisor is an unsigned long
which on some platforms is 64 bit wide. So use div64_ul instead of do_div
to avoid a possible truncation.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Changcheng Deng <deng.changcheng@zte.com.cn>
---
drivers/pwm/pwm-rcar.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c
index b437192380e2..fb475c188e1e 100644
--- a/drivers/pwm/pwm-rcar.c
+++ b/drivers/pwm/pwm-rcar.c
@@ -111,7 +111,7 @@ static int rcar_pwm_set_counter(struct rcar_pwm_chip *rp, int div, int duty_ns,
u32 cyc, ph;

one_cycle = (unsigned long long)NSEC_PER_SEC * 100ULL * (1 << div);
- do_div(one_cycle, clk_rate);
+ one_cycle = div64_ul(one_cycle, clk_rate);

tmp = period_ns * 100ULL;
do_div(tmp, one_cycle);
--
2.25.1
\
 
 \ /
  Last update: 2021-11-18 04:03    [W:0.159 / U:1.452 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site