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 warnings: ./drivers/rtc/rtc-st-lpc.c:96:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_ul instead. ./drivers/rtc/rtc-st-lpc.c:251:1-7: 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/rtc/rtc-st-lpc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-st-lpc.c b/drivers/rtc/rtc-st-lpc.c index bdb20f6..b6e169b 100644 --- a/drivers/rtc/rtc-st-lpc.c +++ b/drivers/rtc/rtc-st-lpc.c @@ -93,7 +93,7 @@ static int st_rtc_read_time(struct device *dev, struct rtc_time *tm) spin_unlock_irqrestore(&rtc->lock, flags); lpt = ((unsigned long long)lpt_msb << 32) | lpt_lsb; - do_div(lpt, rtc->clkrate); + lpt = div64_ul(lpt, rtc->clkrate); rtc_time64_to_tm(lpt, tm); return 0; @@ -248,7 +248,8 @@ static int st_rtc_probe(struct platform_device *pdev) rtc->rtc_dev->ops = &st_rtc_ops; rtc->rtc_dev->range_max = U64_MAX; - do_div(rtc->rtc_dev->range_max, rtc->clkrate); + rtc->rtc_dev->range_max = div64_ul(rtc->rtc_dev->range_max, + rtc->clkrate); ret = devm_rtc_register_device(rtc->rtc_dev); if (ret) { -- 1.8.3.1