[PATCH net-next 2/2] mlx4_en: Only cycle port if HW timestamp config changes

[Shawn Bohrer <shawn.bohrer@gmail.com>]

From: Shawn Bohrer <sbohrer@rgmadvisors.com>

If the hwtstamp_config matches what is currently set for the device then
simply return.  Without this change any program that tries to enable
hardware timestamps will cause the link to cycle even if hardware
timstamps were already enabled.

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_clock.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_clock.c b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
index 9b0d515..cc6a546 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_clock.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_clock.c
@@ -42,6 +42,10 @@ int mlx4_en_timestamp_config(struct net_device *dev, int tx_type, int rx_filter)
 	int port_up = 0;
 	int err = 0;
 
+	if (priv->hwtstamp_config.tx_type == tx_type &&
+	    priv->hwtstamp_config.rx_filter == rx_filter)
+		return 0;
+
 	mutex_lock(&mdev->state_lock);
 	if (priv->port_up) {
 		port_up = 1;
-- 
1.7.7.6