PM: AVS: qcom-cpr: Use div64_ul instead of do_div
authorChangcheng Deng <deng.changcheng@zte.com.cn>
Thu, 25 Nov 2021 01:43:11 +0000 (01:43 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 27 Jan 2022 09:54:17 +0000 (10:54 +0100)
[ Upstream commit 92c550f9ffd2884bb5def52b5c0485a35e452784 ]

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>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20211125014311.45942-1-deng.changcheng@zte.com.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/soc/qcom/cpr.c

index b24cc77..6298561 100644 (file)
@@ -1043,7 +1043,7 @@ static int cpr_interpolate(const struct corner *corner, int step_volt,
                return corner->uV;
 
        temp = f_diff * (uV_high - uV_low);
-       do_div(temp, f_high - f_low);
+       temp = div64_ul(temp, f_high - f_low);
 
        /*
         * max_volt_scale has units of uV/MHz while freq values