[PATCH] clk: imx: use div64_u64() instead of do_div()

Qing Wang wangqing at vivo.com
Wed Feb 9 00:36:58 PST 2022


From: Wang Qing <wangqing at vivo.com>

do_div() does a 64-by-32 division.
When the divisor is u64, do_div() truncates it to 32 bits, this means it
can test non-zero and be truncated to zero for division.

fix do_div.cocci warning:
WARNING: do_div() does a 64-by-32 division, please consider using div64_u64 instead.

Signed-off-by: Wang Qing <wangqing at vivo.com>
---
 drivers/clk/imx/clk-frac-pll.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/imx/clk-frac-pll.c b/drivers/clk/imx/clk-frac-pll.c
index c703056..90b25e3
--- a/drivers/clk/imx/clk-frac-pll.c
+++ b/drivers/clk/imx/clk-frac-pll.c
@@ -129,11 +129,11 @@ static long clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 	parent_rate *= 8;
 	rate *= 2;
 	temp64 = rate;
-	do_div(temp64, parent_rate);
+	div64_u64(temp64, parent_rate);
 	divfi = temp64;
 	temp64 = rate - divfi * parent_rate;
 	temp64 *= PLL_FRAC_DENOM;
-	do_div(temp64, parent_rate);
+	div64_u64(temp64, parent_rate);
 	divff = temp64;
 
 	temp64 = parent_rate;
-- 
2.7.4




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