[bug report] net: ti: am65-cpsw-nuss: Add switchdev support

[Dan Carpenter <dan.carpenter@xxxxxxxxxx>]

Hello Vignesh Raghavendra,

The patch 86e8b070b25e: "net: ti: am65-cpsw-nuss: Add switchdev
support" from Feb 11, 2021, leads to the following Smatch static
checker warning:

	drivers/net/ethernet/ti/am65-cpsw-switchdev.c:187 am65_cpsw_port_vlan_add()
	warn: missing error code? 'ret'

drivers/net/ethernet/ti/am65-cpsw-switchdev.c
    149 static int am65_cpsw_port_vlan_add(struct am65_cpsw_port *port, bool untag, bool pvid,
    150                                    u16 vid, struct net_device *orig_dev)
    151 {
    152         bool cpu_port = netif_is_bridge_master(orig_dev);
    153         struct am65_cpsw_common *cpsw = port->common;
    154         int unreg_mcast_mask = 0;
    155         int reg_mcast_mask = 0;
    156         int untag_mask = 0;
    157         int port_mask;
    158         int ret = 0;
    159         u32 flags;
    160 
    161         if (cpu_port) {
    162                 port_mask = BIT(HOST_PORT_NUM);
    163                 flags = orig_dev->flags;
    164                 unreg_mcast_mask = port_mask;
    165         } else {
    166                 port_mask = BIT(port->port_id);
    167                 flags = port->ndev->flags;
    168         }
    169 
    170         if (flags & IFF_MULTICAST)
    171                 reg_mcast_mask = port_mask;
    172 
    173         if (untag)
    174                 untag_mask = port_mask;
    175 
    176         ret = cpsw_ale_vlan_add_modify(cpsw->ale, vid, port_mask, untag_mask,
    177                                        reg_mcast_mask, unreg_mcast_mask);
    178         if (ret) {
                    ^^^
ret is zero.

    179                 netdev_err(port->ndev, "Unable to add vlan\n");
    180                 return ret;
    181         }
    182 
    183         if (cpu_port)
    184                 cpsw_ale_add_ucast(cpsw->ale, port->slave.mac_addr,
    185                                    HOST_PORT_NUM, ALE_VLAN | ALE_SECURE, vid);
    186         if (!pvid)
--> 187                 return ret;

I think returning zero might have been intentional here, but it would
be better to do an explicit "return 0;"

    188 
    189         am65_cpsw_set_pvid(port, vid, 0, 0);
    190 
    191         netdev_dbg(port->ndev, "VID add: %s: vid:%u ports:%X\n",
    192                    port->ndev->name, vid, port_mask);
    193 
    194         return ret;

Same here too, I suppose, although Smatch doesn't care about this.

    195 }

regards,
dan carpenter