6.6-stable review patch. If anyone has any objections, please let me know.
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From: Sagi Maimon maimon.sagi@gmail.com
[ Upstream commit 2a5970d5aaff8f3e33ce3bfaa403ae88c40de40d ]
In ptp_ocp_signal_set, the start time for periodic signals is not aligned to the next period boundary. The current code rounds up the start time and divides by the period but fails to multiply back by the period, causing misaligned signal starts. Fix this by multiplying the rounded-up value by the period to ensure the start time is the closest next period.
Fixes: 4bd46bb037f8e ("ptp: ocp: Use DIV64_U64_ROUND_UP for rounding.") Signed-off-by: Sagi Maimon maimon.sagi@gmail.com Reviewed-by: Vadim Fedorenko vadim.fedorenko@linux.dev Link: https://patch.msgid.link/20250415053131.129413-1-maimon.sagi@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ptp/ptp_ocp.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/ptp/ptp_ocp.c b/drivers/ptp/ptp_ocp.c index 13343c3198770..4899fdf9bdf7a 100644 --- a/drivers/ptp/ptp_ocp.c +++ b/drivers/ptp/ptp_ocp.c @@ -1842,6 +1842,7 @@ ptp_ocp_signal_set(struct ptp_ocp *bp, int gen, struct ptp_ocp_signal *s) if (!s->start) { /* roundup() does not work on 32-bit systems */ s->start = DIV64_U64_ROUND_UP(start_ns, s->period); + s->start *= s->period; s->start = ktime_add(s->start, s->phase); }