netdev - [PATCH net-next 04/12] net: dpaa2-mac: remove defensive check in dpaa2_mac

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Date:   Tue, 29 Nov 2022 16:12:13 +0200
From:   Vladimir Oltean <vladimir.oltean@....com>
To:     netdev@...r.kernel.org
Cc:     Ioana Ciornei <ioana.ciornei@....com>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Russell King <linux@...linux.org.uk>,
        linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH net-next 04/12] net: dpaa2-mac: remove defensive check in dpaa2_mac_disconnect()

dpaa2_mac_disconnect() will only be called with a NULL mac->phylink if
dpaa2_mac_connect() failed, or was never called.

The callers are these:

dpaa2_eth_disconnect_mac():

	if (dpaa2_eth_is_type_phy(priv))
		dpaa2_mac_disconnect(priv->mac);

dpaa2_switch_port_disconnect_mac():

	if (dpaa2_switch_port_is_type_phy(port_priv))
		dpaa2_mac_disconnect(port_priv->mac);

priv->mac can be NULL, but in that case, dpaa2_eth_is_type_phy() returns
false, and dpaa2_mac_disconnect() is never called. Similar for
dpaa2-switch.

When priv->mac is non-NULL, it means that dpaa2_mac_connect() returned
zero (success), and therefore, priv->mac->phylink is also a valid
pointer.

Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
---
 drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
index c22ce1c871f3..9d1e7026eaef 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c
@@ -449,9 +449,6 @@ int dpaa2_mac_connect(struct dpaa2_mac *mac)
 
 void dpaa2_mac_disconnect(struct dpaa2_mac *mac)
 {
-	if (!mac->phylink)
-		return;
-
 	phylink_disconnect_phy(mac->phylink);
 	phylink_destroy(mac->phylink);
 	dpaa2_pcs_destroy(mac);
-- 
2.34.1