linux-kernel - [PATCH] clk: hisilicon: use div64_u64() instead of do

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Date:   Wed,  9 Feb 2022 00:35:53 -0800
From:   Qing Wang <wangqing@...o.com>
To:     Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>, linux-clk@...r.kernel.org,
        linux-kernel@...r.kernel.org
Cc:     Wang Qing <wangqing@...o.com>
Subject: [PATCH] clk: hisilicon: use div64_u64() instead of do_div()

From: Wang Qing <wangqing@...o.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:
do_div() does a 64-by-32 division, please consider using div64_u64 instead.

Signed-off-by: Wang Qing <wangqing@...o.com>
---
 drivers/clk/hisilicon/clk-hi3559a.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/hisilicon/clk-hi3559a.c b/drivers/clk/hisilicon/clk-hi3559a.c
index 56012a3d..8e90598
--- a/drivers/clk/hisilicon/clk-hi3559a.c
+++ b/drivers/clk/hisilicon/clk-hi3559a.c
@@ -441,8 +441,8 @@ static unsigned long clk_pll_recalc_rate(struct clk_hw *hw,
 	rate = 0;
 	tmp = 24000000 * fbdiv_val + (24000000 * frac_val) / (1 << 24);
 	rate += tmp;
-	do_div(rate, refdiv_val);
-	do_div(rate, postdiv1_val * postdiv2_val);
+	div64_u64(rate, refdiv_val);
+	div64_u64(rate, postdiv1_val * postdiv2_val);
 
 	return rate;
 }
-- 
2.7.4