[PATCH -next] ethernet: renesas: Use div64_ul instead of do_div

From: Yang Li
Date: Wed Nov 17 2021 - 21:50:45 EST


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.

Eliminate the following coccicheck warning:
./drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c:2742:1-7: WARNING:
do_div() does a 64-by-32 division, please consider using div64_ul
instead.

Reported-by: Abaci Robot <abaci@xxxxxxxxxxxxxxxxx>
Signed-off-by: Yang Li <yang.lee@xxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/renesas/ravb_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/renesas/ravb_main.c b/drivers/net/ethernet/renesas/ravb_main.c
index b4c597f..2b89710 100644
--- a/drivers/net/ethernet/renesas/ravb_main.c
+++ b/drivers/net/ethernet/renesas/ravb_main.c
@@ -2489,7 +2489,7 @@ static int ravb_set_gti(struct net_device *ndev)
return -EINVAL;

inc = 1000000000ULL << 20;
- do_div(inc, rate);
+ inc = div64_ul(inc, rate);

if (inc < GTI_TIV_MIN || inc > GTI_TIV_MAX) {
dev_err(dev, "gti.tiv increment 0x%llx is outside the range 0x%x - 0x%x\n",
--
1.8.3.1