[PATCH net-next v3 10/10] net: macb: timer adjust mode is not supported

[Conor Dooley <conor@kernel.org>]

From: Conor Dooley <conor.dooley@microchip.com>

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>
---
 drivers/net/ethernet/cadence/macb_main.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 38e75c2e097bf..3e0ab23e9b9b0 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5577,6 +5577,13 @@ 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.
 	 */
-- 
2.51.0