[PATCH AUTOSEL 5.12 088/116] wilc1000: Bring MAC address setting in line with typical Linux behavior

[Sasha Levin]

From: David Mosberger-Tang <davidm@xxxxxxxxxx>

[ Upstream commit a381b78a1598dde34a6e40dae2842024308a6ef2 ]

Linux network drivers normally disallow changing the MAC address when
the interface is up.  This driver has been different in that it allows
to change the MAC address *only* when it's up.  This patch brings
wilc1000 behavior more in line with other network drivers.  We could
have replaced wilc_set_mac_addr() with eth_mac_addr() but that would
break existing documentation on how to change the MAC address.
Likewise, return -EADDRNOTAVAIL (not -EINVAL) when the specified MAC
address is invalid or unavailable.

Signed-off-by: David Mosberger-Tang <davidm@xxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210303194846.1823596-1-davidm@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 .../net/wireless/microchip/wilc1000/netdev.c  | 25 ++++++++++++-------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/microchip/wilc1000/netdev.c b/drivers/net/wireless/microchip/wilc1000/netdev.c
index 1b205e7d97a8..37f40039e4ca 100644
--- a/drivers/net/wireless/microchip/wilc1000/netdev.c
+++ b/drivers/net/wireless/microchip/wilc1000/netdev.c
@@ -575,7 +575,6 @@ static int wilc_mac_open(struct net_device *ndev)
 {
 	struct wilc_vif *vif = netdev_priv(ndev);
 	struct wilc *wl = vif->wilc;
-	unsigned char mac_add[ETH_ALEN] = {0};
 	int ret = 0;
 	struct mgmt_frame_regs mgmt_regs = {};
 
@@ -598,9 +597,12 @@ static int wilc_mac_open(struct net_device *ndev)
 
 	wilc_set_operation_mode(vif, wilc_get_vif_idx(vif), vif->iftype,
 				vif->idx);
-	wilc_get_mac_address(vif, mac_add);
-	netdev_dbg(ndev, "Mac address: %pM\n", mac_add);
-	ether_addr_copy(ndev->dev_addr, mac_add);
+
+	if (is_valid_ether_addr(ndev->dev_addr))
+		wilc_set_mac_address(vif, ndev->dev_addr);
+	else
+		wilc_get_mac_address(vif, ndev->dev_addr);
+	netdev_dbg(ndev, "Mac address: %pM\n", ndev->dev_addr);
 
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		netdev_err(ndev, "Wrong MAC address\n");
@@ -639,7 +641,14 @@ static int wilc_set_mac_addr(struct net_device *dev, void *p)
 	int srcu_idx;
 
 	if (!is_valid_ether_addr(addr->sa_data))
-		return -EINVAL;
+		return -EADDRNOTAVAIL;
+
+	if (!vif->mac_opened) {
+		eth_commit_mac_addr_change(dev, p);
+		return 0;
+	}
+
+	/* Verify MAC Address is not already in use: */
 
 	srcu_idx = srcu_read_lock(&wilc->srcu);
 	list_for_each_entry_rcu(tmp_vif, &wilc->vif_list, list) {
@@ -647,7 +656,7 @@ static int wilc_set_mac_addr(struct net_device *dev, void *p)
 		if (ether_addr_equal(addr->sa_data, mac_addr)) {
 			if (vif != tmp_vif) {
 				srcu_read_unlock(&wilc->srcu, srcu_idx);
-				return -EINVAL;
+				return -EADDRNOTAVAIL;
 			}
 			srcu_read_unlock(&wilc->srcu, srcu_idx);
 			return 0;
@@ -659,9 +668,7 @@ static int wilc_set_mac_addr(struct net_device *dev, void *p)
 	if (result)
 		return result;
 
-	ether_addr_copy(vif->bssid, addr->sa_data);
-	ether_addr_copy(vif->ndev->dev_addr, addr->sa_data);
-
+	eth_commit_mac_addr_change(dev, p);
 	return result;
 }
 
-- 
2.30.2