[RFC net-next v1 6/7] net: macb: afaict, the driver doesn't support tsu timer adjust mode

Conor Dooley
2025-11-20T16:26:58Z

The ptp portion of this driver controls the tsu's timer, which is not
compatible with the hardware trying to control it via the
gem_tsu_inc_ctrl and gem_tsu_ms inputs afaict. Abort probe if someone
tries to use it.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
drivers/net/ethernet/cadence/macb_main.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 21045575f19c..4ad1409dab63 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5531,6 +5531,12 @@ 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");
+ goto err_out_free_netdev;
+ }
+
/* By default we set to partial store and forward mode for zynqmp.
* Disable if not set in devicetree.
*/
--
2.51.0