net: macb: timer adjust mode is not supported

The ptp portion of this driver controls the tsu's timer using the
controls for "increment mode", which is not compatible with the hardware
trying to control it via the gem_tsu_inc_ctrl and gem_tsu_ms inputs in
"timer adjust mode". Abort probe if the property signalling that the
relevant signals have been wired up is present.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://patch.msgid.link/20260325-facebook-chop-cf792c53f1da@spud
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 7deae61a61d4968ecc3f7c7c9a789e5a385d759f..11074938c6bb721e64f8715ab8065e5b26ba3f6b 100644 (file)
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5838,6 +5838,13 @@ static int macb_probe(struct platform_device *pdev)
 
        bp->usrio = macb_config->usrio;
 
+       if (of_property_read_bool(bp->pdev->dev.of_node, "cdns,timer-adjust") &&
+                       IS_ENABLED(CONFIG_MACB_USE_HWSTAMP)) {
+               dev_err(&pdev->dev, "Timer adjust mode is not supported\n");
+               err = -EINVAL;
+               goto err_out_free_netdev;
+       }
+
        /* By default we set to partial store and forward mode for zynqmp.
         * Disable if not set in devicetree.
         */