From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH] net: macb: Fix ptp time adjustment for large negative delta Date: Wed, 20 Jun 2018 16:04:17 +0200 Message-ID: References: <1529494460-4689-1-git-send-email-harini.katakam@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: , , , , Claudiu Beznea - M18063 To: Harini Katakam , Return-path: In-Reply-To: <1529494460-4689-1-git-send-email-harini.katakam@xilinx.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On 20/06/2018 at 13:34, Harini Katakam wrote: > When delta passed to gem_ptp_adjtime is negative, the sign is > maintained in the ns_to_timespec64 conversion. Hence timespec_add > should be used directly. timespec_sub will just subtract the negative > value thus increasing the time difference. > > Signed-off-by: Harini Katakam Makes sense: Acked-by: Nicolas Ferre > --- > drivers/net/ethernet/cadence/macb_ptp.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/drivers/net/ethernet/cadence/macb_ptp.c b/drivers/net/ethernet/cadence/macb_ptp.c > index 2220c77..6788351 100644 > --- a/drivers/net/ethernet/cadence/macb_ptp.c > +++ b/drivers/net/ethernet/cadence/macb_ptp.c > @@ -170,10 +170,7 @@ static int gem_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) > > if (delta > TSU_NSEC_MAX_VAL) { > gem_tsu_get_time(&bp->ptp_clock_info, &now); > - if (sign) > - now = timespec64_sub(now, then); > - else > - now = timespec64_add(now, then); > + now = timespec64_add(now, then); > > gem_tsu_set_time(&bp->ptp_clock_info, > (const struct timespec64 *)&now); > -- Nicolas Ferre