Subject: [net 06/18] net/mlx5e: Revert parameters on errors when changing PTP state without reset

From: Saeed Mahameed <[email-masked]>
Date: Wed, 10 Mar 2021 11:03:30 -0800

From: Maxim Mikityanskiy <[email-masked]>

Port timestamping for PTP can be enabled/disabled while the channels are
closed. In that case mlx5e_safe_switch_channels is skipped, and the
preactivate hook is called directly. However, if that hook returns an
error, the channel parameters must be reverted back to their old values.
This commit adds missing handling on this case.

Fixes: 145e5637d941 ("net/mlx5e: Add TX PTP port object support")
Signed-off-by: Maxim Mikityanskiy <[email-masked]>
Reviewed-by: Tariq Toukan <[email-masked]>
Signed-off-by: Saeed Mahameed <[email-masked]>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index abdf721bb264..0e059d5c57ac 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -2014,8 +2014,13 @@ static int set_pflag_tx_port_ts(struct net_device *netdev, bool enable)
 	 */
 
 	if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) {
+		struct mlx5e_params old_params;
+
+		old_params = priv->channels.params;
 		priv->channels.params = new_channels.params;
 		err = mlx5e_num_channels_changed(priv);
+		if (err)
+			priv->channels.params = old_params;
 		goto out;
 	}
 
-- 
2.29.2