Commit c0a1f3d7e128 for kernel

commit c0a1f3d7e128e8d1b6c0fe09c68eac5ebcf677c8
Author: Wei Fang <wei.fang@nxp.com>
Date:   Tue Nov 25 16:52:09 2025 +0800

    net: fec: do not allow enabling PPS and PEROUT simultaneously

    In the current driver, PPS and PEROUT use the same channel to generate
    the events, so they cannot be enabled at the same time. Otherwise, the
    later configuration will overwrite the earlier configuration. Therefore,
    when configuring PPS, the driver will check whether PEROUT is enabled.
    Similarly, when configuring PEROUT, the driver will check whether PPS
    is enabled.

    Fixes: 350749b909bf ("net: fec: Add support for periodic output signal of PPS")
    Signed-off-by: Wei Fang <wei.fang@nxp.com>
    Link: https://patch.msgid.link/20251125085210.1094306-4-wei.fang@nxp.com
    Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c
index f31b1626c12f..ed5d59abeb53 100644
--- a/drivers/net/ethernet/freescale/fec_ptp.c
+++ b/drivers/net/ethernet/freescale/fec_ptp.c
@@ -128,6 +128,12 @@ static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable)

 	spin_lock_irqsave(&fep->tmreg_lock, flags);

+	if (fep->perout_enable) {
+		spin_unlock_irqrestore(&fep->tmreg_lock, flags);
+		dev_err(&fep->pdev->dev, "PEROUT is running");
+		return -EBUSY;
+	}
+
 	if (fep->pps_enable == enable) {
 		spin_unlock_irqrestore(&fep->tmreg_lock, flags);
 		return 0;
@@ -571,6 +577,12 @@ static int fec_ptp_enable(struct ptp_clock_info *ptp,
 			}
 			spin_lock_irqsave(&fep->tmreg_lock, flags);

+			if (fep->pps_enable) {
+				dev_err(&fep->pdev->dev, "PPS is running");
+				ret = -EBUSY;
+				goto unlock;
+			}
+
 			if (fep->perout_enable) {
 				dev_err(&fep->pdev->dev,
 					"PEROUT has been enabled\n");