net/dsa/slave.c - kernel/msm-4.19 - Gitiles

 /*
  * net/dsa/slave.c - Slave device handling
  * Copyright (c) 2008-2009 Marvell Semiconductor
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include <linux/list.h>
 #include <linux/etherdevice.h>
 #include <linux/netdevice.h>
 #include <linux/phy.h>
 #include <linux/phy_fixed.h>
 #include <linux/of_net.h>
 #include <linux/of_mdio.h>
 #include <net/rtnetlink.h>
 #include <net/switchdev.h>
 #include <linux/if_bridge.h>
 #include "dsa_priv.h"

 /* slave mii_bus handling ***************************************************/
 static int dsa_slave_phy_read(struct mii_bus *bus, int addr, int reg)
 {
 	struct dsa_switch *ds = bus->priv;

 	if (ds->phys_mii_mask & (1 << addr))
 		return ds->drv->phy_read(ds, addr, reg);

 	return 0xffff;
 }

 static int dsa_slave_phy_write(struct mii_bus *bus, int addr, int reg, u16 val)
 {
 	struct dsa_switch *ds = bus->priv;

 	if (ds->phys_mii_mask & (1 << addr))
 		return ds->drv->phy_write(ds, addr, reg, val);

 	return 0;
 }

 void dsa_slave_mii_bus_init(struct dsa_switch *ds)
 {
 	ds->slave_mii_bus->priv = (void *)ds;
 	ds->slave_mii_bus->name = "dsa slave smi";
 	ds->slave_mii_bus->read = dsa_slave_phy_read;
 	ds->slave_mii_bus->write = dsa_slave_phy_write;
 	snprintf(ds->slave_mii_bus->id, MII_BUS_ID_SIZE, "dsa-%d:%.2x",
 			ds->index, ds->pd->sw_addr);
 	ds->slave_mii_bus->parent = ds->master_dev;
 	ds->slave_mii_bus->phy_mask = ~ds->phys_mii_mask;
 }


 /* slave device handling ****************************************************/
 static int dsa_slave_init(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	dev->iflink = p->parent->dst->master_netdev->ifindex;

 	return 0;
 }

 static inline bool dsa_port_is_bridged(struct dsa_slave_priv *p)
 {
 	return !!p->bridge_dev;
 }

 static int dsa_slave_open(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct net_device *master = p->parent->dst->master_netdev;
 	struct dsa_switch *ds = p->parent;
 	u8 stp_state = dsa_port_is_bridged(p) ?
 			BR_STATE_BLOCKING : BR_STATE_FORWARDING;
 	int err;

 	if (!(master->flags & IFF_UP))
 		return -ENETDOWN;

 	if (!ether_addr_equal(dev->dev_addr, master->dev_addr)) {
 		err = dev_uc_add(master, dev->dev_addr);
 		if (err < 0)
 			goto out;
 	}

 	if (dev->flags & IFF_ALLMULTI) {
 		err = dev_set_allmulti(master, 1);
 		if (err < 0)
 			goto del_unicast;
 	}
 	if (dev->flags & IFF_PROMISC) {
 		err = dev_set_promiscuity(master, 1);
 		if (err < 0)
 			goto clear_allmulti;
 	}

 	if (ds->drv->port_enable) {
 		err = ds->drv->port_enable(ds, p->port, p->phy);
 		if (err)
 			goto clear_promisc;
 	}

 	if (ds->drv->port_stp_update)
 		ds->drv->port_stp_update(ds, p->port, stp_state);

 	if (p->phy)
 		phy_start(p->phy);

 	return 0;

 clear_promisc:
 	if (dev->flags & IFF_PROMISC)
 		dev_set_promiscuity(master, 0);
 clear_allmulti:
 	if (dev->flags & IFF_ALLMULTI)
 		dev_set_allmulti(master, -1);
 del_unicast:
 	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
 		dev_uc_del(master, dev->dev_addr);
 out:
 	return err;
 }

 static int dsa_slave_close(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct net_device *master = p->parent->dst->master_netdev;
 	struct dsa_switch *ds = p->parent;

 	if (p->phy)
 		phy_stop(p->phy);

 	dev_mc_unsync(master, dev);
 	dev_uc_unsync(master, dev);
 	if (dev->flags & IFF_ALLMULTI)
 		dev_set_allmulti(master, -1);
 	if (dev->flags & IFF_PROMISC)
 		dev_set_promiscuity(master, -1);

 	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
 		dev_uc_del(master, dev->dev_addr);

 	if (ds->drv->port_disable)
 		ds->drv->port_disable(ds, p->port, p->phy);

 	if (ds->drv->port_stp_update)
 		ds->drv->port_stp_update(ds, p->port, BR_STATE_DISABLED);

 	return 0;
 }

 static void dsa_slave_change_rx_flags(struct net_device *dev, int change)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct net_device *master = p->parent->dst->master_netdev;

 	if (change & IFF_ALLMULTI)
 		dev_set_allmulti(master, dev->flags & IFF_ALLMULTI ? 1 : -1);
 	if (change & IFF_PROMISC)
 		dev_set_promiscuity(master, dev->flags & IFF_PROMISC ? 1 : -1);
 }

 static void dsa_slave_set_rx_mode(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct net_device *master = p->parent->dst->master_netdev;

 	dev_mc_sync(master, dev);
 	dev_uc_sync(master, dev);
 }

 static int dsa_slave_set_mac_address(struct net_device *dev, void *a)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct net_device *master = p->parent->dst->master_netdev;
 	struct sockaddr *addr = a;
 	int err;

 	if (!is_valid_ether_addr(addr->sa_data))
 		return -EADDRNOTAVAIL;

 	if (!(dev->flags & IFF_UP))
 		goto out;

 	if (!ether_addr_equal(addr->sa_data, master->dev_addr)) {
 		err = dev_uc_add(master, addr->sa_data);
 		if (err < 0)
 			return err;
 	}

 	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
 		dev_uc_del(master, dev->dev_addr);

 out:
 	ether_addr_copy(dev->dev_addr, addr->sa_data);

 	return 0;
 }

 static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	if (p->phy != NULL)
 		return phy_mii_ioctl(p->phy, ifr, cmd);

 	return -EOPNOTSUPP;
 }

 /* Return a bitmask of all ports being currently bridged within a given bridge
  * device. Note that on leave, the mask will still return the bitmask of ports
  * currently bridged, prior to port removal, and this is exactly what we want.
  */
 static u32 dsa_slave_br_port_mask(struct dsa_switch *ds,
 				  struct net_device *bridge)
 {
 	struct dsa_slave_priv *p;
 	unsigned int port;
 	u32 mask = 0;

 	for (port = 0; port < DSA_MAX_PORTS; port++) {
 		if (!dsa_is_port_initialized(ds, port))
 			continue;

 		p = netdev_priv(ds->ports[port]);

 		if (ds->ports[port]->priv_flags & IFF_BRIDGE_PORT &&
 		    p->bridge_dev == bridge)
 			mask |= 1 << port;
 	}

 	return mask;
 }

 static int dsa_slave_stp_update(struct net_device *dev, u8 state)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret = -EOPNOTSUPP;

 	if (ds->drv->port_stp_update)
 		ret = ds->drv->port_stp_update(ds, p->port, state);

 	return ret;
 }

 static int dsa_slave_bridge_port_join(struct net_device *dev,
 				      struct net_device *br)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret = -EOPNOTSUPP;

 	p->bridge_dev = br;

 	if (ds->drv->port_join_bridge)
 		ret = ds->drv->port_join_bridge(ds, p->port,
 						dsa_slave_br_port_mask(ds, br));

 	return ret;
 }

 static int dsa_slave_bridge_port_leave(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret = -EOPNOTSUPP;


 	if (ds->drv->port_leave_bridge)
 		ret = ds->drv->port_leave_bridge(ds, p->port,
 						 dsa_slave_br_port_mask(ds, p->bridge_dev));

 	p->bridge_dev = NULL;

 	/* Port left the bridge, put in BR_STATE_DISABLED by the bridge layer,
 	 * so allow it to be in BR_STATE_FORWARDING to be kept functional
 	 */
 	dsa_slave_stp_update(dev, BR_STATE_FORWARDING);

 	return ret;
 }

 static int dsa_slave_parent_id_get(struct net_device *dev,
 				   struct netdev_phys_item_id *psid)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	psid->id_len = sizeof(ds->index);
 	memcpy(&psid->id, &ds->index, psid->id_len);

 	return 0;
 }

 static netdev_tx_t dsa_slave_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	return p->xmit(skb, dev);
 }

 static netdev_tx_t dsa_slave_notag_xmit(struct sk_buff *skb,
 					struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	skb->dev = p->parent->dst->master_netdev;
 	dev_queue_xmit(skb);

 	return NETDEV_TX_OK;
 }


 /* ethtool operations *******************************************************/
 static int
 dsa_slave_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	int err;

 	err = -EOPNOTSUPP;
 	if (p->phy != NULL) {
 		err = phy_read_status(p->phy);
 		if (err == 0)
 			err = phy_ethtool_gset(p->phy, cmd);
 	}

 	return err;
 }

 static int
 dsa_slave_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	if (p->phy != NULL)
 		return phy_ethtool_sset(p->phy, cmd);

 	return -EOPNOTSUPP;
 }

 static void dsa_slave_get_drvinfo(struct net_device *dev,
 				  struct ethtool_drvinfo *drvinfo)
 {
 	strlcpy(drvinfo->driver, "dsa", sizeof(drvinfo->driver));
 	strlcpy(drvinfo->version, dsa_driver_version, sizeof(drvinfo->version));
 	strlcpy(drvinfo->fw_version, "N/A", sizeof(drvinfo->fw_version));
 	strlcpy(drvinfo->bus_info, "platform", sizeof(drvinfo->bus_info));
 }

 static int dsa_slave_get_regs_len(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->get_regs_len)
 		return ds->drv->get_regs_len(ds, p->port);

 	return -EOPNOTSUPP;
 }

 static void
 dsa_slave_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *_p)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->get_regs)
 		ds->drv->get_regs(ds, p->port, regs, _p);
 }

 static int dsa_slave_nway_reset(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	if (p->phy != NULL)
 		return genphy_restart_aneg(p->phy);

 	return -EOPNOTSUPP;
 }

 static u32 dsa_slave_get_link(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);

 	if (p->phy != NULL) {
 		genphy_update_link(p->phy);
 		return p->phy->link;
 	}

 	return -EOPNOTSUPP;
 }

 static int dsa_slave_get_eeprom_len(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->pd->eeprom_len)
 		return ds->pd->eeprom_len;

 	if (ds->drv->get_eeprom_len)
 		return ds->drv->get_eeprom_len(ds);

 	return 0;
 }

 static int dsa_slave_get_eeprom(struct net_device *dev,
 				struct ethtool_eeprom *eeprom, u8 *data)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->get_eeprom)
 		return ds->drv->get_eeprom(ds, eeprom, data);

 	return -EOPNOTSUPP;
 }

 static int dsa_slave_set_eeprom(struct net_device *dev,
 				struct ethtool_eeprom *eeprom, u8 *data)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->set_eeprom)
 		return ds->drv->set_eeprom(ds, eeprom, data);

 	return -EOPNOTSUPP;
 }

 static void dsa_slave_get_strings(struct net_device *dev,
 				  uint32_t stringset, uint8_t *data)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (stringset == ETH_SS_STATS) {
 		int len = ETH_GSTRING_LEN;

 		strncpy(data, "tx_packets", len);
 		strncpy(data + len, "tx_bytes", len);
 		strncpy(data + 2 * len, "rx_packets", len);
 		strncpy(data + 3 * len, "rx_bytes", len);
 		if (ds->drv->get_strings != NULL)
 			ds->drv->get_strings(ds, p->port, data + 4 * len);
 	}
 }

 static void dsa_slave_get_ethtool_stats(struct net_device *dev,
 					struct ethtool_stats *stats,
 					uint64_t *data)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	data[0] = p->dev->stats.tx_packets;
 	data[1] = p->dev->stats.tx_bytes;
 	data[2] = p->dev->stats.rx_packets;
 	data[3] = p->dev->stats.rx_bytes;
 	if (ds->drv->get_ethtool_stats != NULL)
 		ds->drv->get_ethtool_stats(ds, p->port, data + 4);
 }

 static int dsa_slave_get_sset_count(struct net_device *dev, int sset)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (sset == ETH_SS_STATS) {
 		int count;

 		count = 4;
 		if (ds->drv->get_sset_count != NULL)
 			count += ds->drv->get_sset_count(ds);

 		return count;
 	}

 	return -EOPNOTSUPP;
 }

 static void dsa_slave_get_wol(struct net_device *dev, struct ethtool_wolinfo *w)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->get_wol)
 		ds->drv->get_wol(ds, p->port, w);
 }

 static int dsa_slave_set_wol(struct net_device *dev, struct ethtool_wolinfo *w)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret = -EOPNOTSUPP;

 	if (ds->drv->set_wol)
 		ret = ds->drv->set_wol(ds, p->port, w);

 	return ret;
 }

 static int dsa_slave_set_eee(struct net_device *dev, struct ethtool_eee *e)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret;

 	if (!ds->drv->set_eee)
 		return -EOPNOTSUPP;

 	ret = ds->drv->set_eee(ds, p->port, p->phy, e);
 	if (ret)
 		return ret;

 	if (p->phy)
 		ret = phy_ethtool_set_eee(p->phy, e);

 	return ret;
 }

 static int dsa_slave_get_eee(struct net_device *dev, struct ethtool_eee *e)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	int ret;

 	if (!ds->drv->get_eee)
 		return -EOPNOTSUPP;

 	ret = ds->drv->get_eee(ds, p->port, e);
 	if (ret)
 		return ret;

 	if (p->phy)
 		ret = phy_ethtool_get_eee(p->phy, e);

 	return ret;
 }

 static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.get_settings		= dsa_slave_get_settings,
 	.set_settings		= dsa_slave_set_settings,
 	.get_drvinfo		= dsa_slave_get_drvinfo,
 	.get_regs_len		= dsa_slave_get_regs_len,
 	.get_regs		= dsa_slave_get_regs,
 	.nway_reset		= dsa_slave_nway_reset,
 	.get_link		= dsa_slave_get_link,
 	.get_eeprom_len		= dsa_slave_get_eeprom_len,
 	.get_eeprom		= dsa_slave_get_eeprom,
 	.set_eeprom		= dsa_slave_set_eeprom,
 	.get_strings		= dsa_slave_get_strings,
 	.get_ethtool_stats	= dsa_slave_get_ethtool_stats,
 	.get_sset_count		= dsa_slave_get_sset_count,
 	.set_wol		= dsa_slave_set_wol,
 	.get_wol		= dsa_slave_get_wol,
 	.set_eee		= dsa_slave_set_eee,
 	.get_eee		= dsa_slave_get_eee,
 };

 static const struct net_device_ops dsa_slave_netdev_ops = {
 	.ndo_init		= dsa_slave_init,
 	.ndo_open	 	= dsa_slave_open,
 	.ndo_stop		= dsa_slave_close,
 	.ndo_start_xmit		= dsa_slave_xmit,
 	.ndo_change_rx_flags	= dsa_slave_change_rx_flags,
 	.ndo_set_rx_mode	= dsa_slave_set_rx_mode,
 	.ndo_set_mac_address	= dsa_slave_set_mac_address,
 	.ndo_do_ioctl		= dsa_slave_ioctl,
 };

 static const struct swdev_ops dsa_slave_swdev_ops = {
 	.swdev_parent_id_get = dsa_slave_parent_id_get,
 	.swdev_port_stp_update = dsa_slave_stp_update,
 };

 static void dsa_slave_adjust_link(struct net_device *dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;
 	unsigned int status_changed = 0;

 	if (p->old_link != p->phy->link) {
 		status_changed = 1;
 		p->old_link = p->phy->link;
 	}

 	if (p->old_duplex != p->phy->duplex) {
 		status_changed = 1;
 		p->old_duplex = p->phy->duplex;
 	}

 	if (p->old_pause != p->phy->pause) {
 		status_changed = 1;
 		p->old_pause = p->phy->pause;
 	}

 	if (ds->drv->adjust_link && status_changed)
 		ds->drv->adjust_link(ds, p->port, p->phy);

 	if (status_changed)
 		phy_print_status(p->phy);
 }

 static int dsa_slave_fixed_link_update(struct net_device *dev,
 				       struct fixed_phy_status *status)
 {
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_switch *ds = p->parent;

 	if (ds->drv->fixed_link_update)
 		ds->drv->fixed_link_update(ds, p->port, status);

 	return 0;
 }

 /* slave device setup *******************************************************/
 static int dsa_slave_phy_connect(struct dsa_slave_priv *p,
 				 struct net_device *slave_dev,
 				 int addr)
 {
 	struct dsa_switch *ds = p->parent;

 	p->phy = ds->slave_mii_bus->phy_map[addr];
 	if (!p->phy)
 		return -ENODEV;

 	/* Use already configured phy mode */
 	p->phy_interface = p->phy->interface;
 	phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link,
 			   p->phy_interface);

 	return 0;
 }

 static int dsa_slave_phy_setup(struct dsa_slave_priv *p,
 				struct net_device *slave_dev)
 {
 	struct dsa_switch *ds = p->parent;
 	struct dsa_chip_data *cd = ds->pd;
 	struct device_node *phy_dn, *port_dn;
 	bool phy_is_fixed = false;
 	u32 phy_flags = 0;
 	int mode, ret;

 	port_dn = cd->port_dn[p->port];
 	mode = of_get_phy_mode(port_dn);
 	if (mode < 0)
 		mode = PHY_INTERFACE_MODE_NA;
 	p->phy_interface = mode;

 	phy_dn = of_parse_phandle(port_dn, "phy-handle", 0);
 	if (of_phy_is_fixed_link(port_dn)) {
 		/* In the case of a fixed PHY, the DT node associated
 		 * to the fixed PHY is the Port DT node
 		 */
 		ret = of_phy_register_fixed_link(port_dn);
 		if (ret) {
 			netdev_err(slave_dev, "failed to register fixed PHY\n");
 			return ret;
 		}
 		phy_is_fixed = true;
 		phy_dn = port_dn;
 	}

 	if (ds->drv->get_phy_flags)
 		phy_flags = ds->drv->get_phy_flags(ds, p->port);

 	if (phy_dn) {
 		ret = of_mdio_parse_addr(&slave_dev->dev, phy_dn);
 		/* If this PHY address is part of phys_mii_mask, which means
 		 * that we need to divert reads and writes to/from it, then we
 		 * want to bind this device using the slave MII bus created by
 		 * DSA to make that happen.
 		 */
 		if (!phy_is_fixed && ret >= 0 &&
 		    (ds->phys_mii_mask & (1 << ret))) {
 			ret = dsa_slave_phy_connect(p, slave_dev, ret);
 			if (ret)
 				return ret;
 		} else {
 			p->phy = of_phy_connect(slave_dev, phy_dn,
 						dsa_slave_adjust_link,
 						phy_flags,
 						p->phy_interface);
 		}
 	}

 	if (p->phy && phy_is_fixed)
 		fixed_phy_set_link_update(p->phy, dsa_slave_fixed_link_update);

 	/* We could not connect to a designated PHY, so use the switch internal
 	 * MDIO bus instead
 	 */
 	if (!p->phy) {
 		ret = dsa_slave_phy_connect(p, slave_dev, p->port);
 		if (ret)
 			return ret;
 	} else {
 		netdev_info(slave_dev, "attached PHY at address %d [%s]\n",
 			    p->phy->addr, p->phy->drv->name);
 	}

 	return 0;
 }

 int dsa_slave_suspend(struct net_device *slave_dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(slave_dev);

 	netif_device_detach(slave_dev);

 	if (p->phy) {
 		phy_stop(p->phy);
 		p->old_pause = -1;
 		p->old_link = -1;
 		p->old_duplex = -1;
 		phy_suspend(p->phy);
 	}

 	return 0;
 }

 int dsa_slave_resume(struct net_device *slave_dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(slave_dev);

 	netif_device_attach(slave_dev);

 	if (p->phy) {
 		phy_resume(p->phy);
 		phy_start(p->phy);
 	}

 	return 0;
 }

 int dsa_slave_create(struct dsa_switch *ds, struct device *parent,
 		     int port, char *name)
 {
 	struct net_device *master = ds->dst->master_netdev;
 	struct net_device *slave_dev;
 	struct dsa_slave_priv *p;
 	int ret;

 	slave_dev = alloc_netdev(sizeof(struct dsa_slave_priv), name,
 				 NET_NAME_UNKNOWN, ether_setup);
 	if (slave_dev == NULL)
 		return -ENOMEM;

 	slave_dev->features = master->vlan_features;
 	slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
 	eth_hw_addr_inherit(slave_dev, master);
 	slave_dev->tx_queue_len = 0;
 	slave_dev->netdev_ops = &dsa_slave_netdev_ops;
 	slave_dev->swdev_ops = &dsa_slave_swdev_ops;

 	SET_NETDEV_DEV(slave_dev, parent);
 	slave_dev->dev.of_node = ds->pd->port_dn[port];
 	slave_dev->vlan_features = master->vlan_features;

 	p = netdev_priv(slave_dev);
 	p->dev = slave_dev;
 	p->parent = ds;
 	p->port = port;

 	switch (ds->dst->tag_protocol) {
 #ifdef CONFIG_NET_DSA_TAG_DSA
 	case DSA_TAG_PROTO_DSA:
 		p->xmit = dsa_netdev_ops.xmit;
 		break;
 #endif
 #ifdef CONFIG_NET_DSA_TAG_EDSA
 	case DSA_TAG_PROTO_EDSA:
 		p->xmit = edsa_netdev_ops.xmit;
 		break;
 #endif
 #ifdef CONFIG_NET_DSA_TAG_TRAILER
 	case DSA_TAG_PROTO_TRAILER:
 		p->xmit = trailer_netdev_ops.xmit;
 		break;
 #endif
 #ifdef CONFIG_NET_DSA_TAG_BRCM
 	case DSA_TAG_PROTO_BRCM:
 		p->xmit = brcm_netdev_ops.xmit;
 		break;
 #endif
 	default:
 		p->xmit	= dsa_slave_notag_xmit;
 		break;
 	}

 	p->old_pause = -1;
 	p->old_link = -1;
 	p->old_duplex = -1;

 	ret = dsa_slave_phy_setup(p, slave_dev);
 	if (ret) {
 		free_netdev(slave_dev);
 		return ret;
 	}

 	ds->ports[port] = slave_dev;
 	ret = register_netdev(slave_dev);
 	if (ret) {
 		netdev_err(master, "error %d registering interface %s\n",
 			   ret, slave_dev->name);
 		phy_disconnect(p->phy);
 		ds->ports[port] = NULL;
 		free_netdev(slave_dev);
 		return ret;
 	}

 	netif_carrier_off(slave_dev);

 	return 0;
 }

 static bool dsa_slave_dev_check(struct net_device *dev)
 {
 	return dev->netdev_ops == &dsa_slave_netdev_ops;
 }

 static int dsa_slave_master_changed(struct net_device *dev)
 {
 	struct net_device *master = netdev_master_upper_dev_get(dev);
 	int err = 0;

 	if (master && master->rtnl_link_ops &&
 	    !strcmp(master->rtnl_link_ops->kind, "bridge"))
 		err = dsa_slave_bridge_port_join(dev, master);
 	else
 		err = dsa_slave_bridge_port_leave(dev);

 	return err;
 }

 int dsa_slave_netdevice_event(struct notifier_block *unused,
 			      unsigned long event, void *ptr)
 {
 	struct net_device *dev;
 	int err = 0;

 	switch (event) {
 	case NETDEV_CHANGEUPPER:
 		dev = netdev_notifier_info_to_dev(ptr);
 		if (!dsa_slave_dev_check(dev))
 			goto out;

 		err = dsa_slave_master_changed(dev);
 		if (err)
 			netdev_warn(dev, "failed to reflect master change\n");

 		break;
 	}

 out:
 	return NOTIFY_DONE;
 }
	/*
	* net/dsa/slave.c - Slave device handling
	* Copyright (c) 2008-2009 Marvell Semiconductor
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include <linux/list.h>
	#include <linux/etherdevice.h>
	#include <linux/netdevice.h>
	#include <linux/phy.h>
	#include <linux/phy_fixed.h>
	#include <linux/of_net.h>
	#include <linux/of_mdio.h>
	#include <net/rtnetlink.h>
	#include <net/switchdev.h>
	#include <linux/if_bridge.h>
	#include "dsa_priv.h"

	/* slave mii_bus handling ***************************************************/
	static int dsa_slave_phy_read(struct mii_bus *bus, int addr, int reg)
	{
	struct dsa_switch *ds = bus->priv;

	if (ds->phys_mii_mask & (1 << addr))
	return ds->drv->phy_read(ds, addr, reg);

	return 0xffff;
	}

	static int dsa_slave_phy_write(struct mii_bus *bus, int addr, int reg, u16 val)
	{
	struct dsa_switch *ds = bus->priv;

	if (ds->phys_mii_mask & (1 << addr))
	return ds->drv->phy_write(ds, addr, reg, val);

	return 0;
	}

	void dsa_slave_mii_bus_init(struct dsa_switch *ds)
	{
	ds->slave_mii_bus->priv = (void *)ds;
	ds->slave_mii_bus->name = "dsa slave smi";
	ds->slave_mii_bus->read = dsa_slave_phy_read;
	ds->slave_mii_bus->write = dsa_slave_phy_write;
	snprintf(ds->slave_mii_bus->id, MII_BUS_ID_SIZE, "dsa-%d:%.2x",
	ds->index, ds->pd->sw_addr);
	ds->slave_mii_bus->parent = ds->master_dev;
	ds->slave_mii_bus->phy_mask = ~ds->phys_mii_mask;
	}


	/* slave device handling ****************************************************/
	static int dsa_slave_init(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	dev->iflink = p->parent->dst->master_netdev->ifindex;

	return 0;
	}

	static inline bool dsa_port_is_bridged(struct dsa_slave_priv *p)
	{
	return !!p->bridge_dev;
	}

	static int dsa_slave_open(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct net_device *master = p->parent->dst->master_netdev;
	struct dsa_switch *ds = p->parent;
	u8 stp_state = dsa_port_is_bridged(p) ?
	BR_STATE_BLOCKING : BR_STATE_FORWARDING;
	int err;

	if (!(master->flags & IFF_UP))
	return -ENETDOWN;

	if (!ether_addr_equal(dev->dev_addr, master->dev_addr)) {
	err = dev_uc_add(master, dev->dev_addr);
	if (err < 0)
	goto out;
	}

	if (dev->flags & IFF_ALLMULTI) {
	err = dev_set_allmulti(master, 1);
	if (err < 0)
	goto del_unicast;
	}
	if (dev->flags & IFF_PROMISC) {
	err = dev_set_promiscuity(master, 1);
	if (err < 0)
	goto clear_allmulti;
	}

	if (ds->drv->port_enable) {
	err = ds->drv->port_enable(ds, p->port, p->phy);
	if (err)
	goto clear_promisc;
	}

	if (ds->drv->port_stp_update)
	ds->drv->port_stp_update(ds, p->port, stp_state);

	if (p->phy)
	phy_start(p->phy);

	return 0;

	clear_promisc:
	if (dev->flags & IFF_PROMISC)
	dev_set_promiscuity(master, 0);
	clear_allmulti:
	if (dev->flags & IFF_ALLMULTI)
	dev_set_allmulti(master, -1);
	del_unicast:
	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
	dev_uc_del(master, dev->dev_addr);
	out:
	return err;
	}

	static int dsa_slave_close(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct net_device *master = p->parent->dst->master_netdev;
	struct dsa_switch *ds = p->parent;

	if (p->phy)
	phy_stop(p->phy);

	dev_mc_unsync(master, dev);
	dev_uc_unsync(master, dev);
	if (dev->flags & IFF_ALLMULTI)
	dev_set_allmulti(master, -1);
	if (dev->flags & IFF_PROMISC)
	dev_set_promiscuity(master, -1);

	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
	dev_uc_del(master, dev->dev_addr);

	if (ds->drv->port_disable)
	ds->drv->port_disable(ds, p->port, p->phy);

	if (ds->drv->port_stp_update)
	ds->drv->port_stp_update(ds, p->port, BR_STATE_DISABLED);

	return 0;
	}

	static void dsa_slave_change_rx_flags(struct net_device *dev, int change)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct net_device *master = p->parent->dst->master_netdev;

	if (change & IFF_ALLMULTI)
	dev_set_allmulti(master, dev->flags & IFF_ALLMULTI ? 1 : -1);
	if (change & IFF_PROMISC)
	dev_set_promiscuity(master, dev->flags & IFF_PROMISC ? 1 : -1);
	}

	static void dsa_slave_set_rx_mode(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct net_device *master = p->parent->dst->master_netdev;

	dev_mc_sync(master, dev);
	dev_uc_sync(master, dev);
	}

	static int dsa_slave_set_mac_address(struct net_device dev, void a)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct net_device *master = p->parent->dst->master_netdev;
	struct sockaddr *addr = a;
	int err;

	if (!is_valid_ether_addr(addr->sa_data))
	return -EADDRNOTAVAIL;

	if (!(dev->flags & IFF_UP))
	goto out;

	if (!ether_addr_equal(addr->sa_data, master->dev_addr)) {
	err = dev_uc_add(master, addr->sa_data);
	if (err < 0)
	return err;
	}

	if (!ether_addr_equal(dev->dev_addr, master->dev_addr))
	dev_uc_del(master, dev->dev_addr);

	out:
	ether_addr_copy(dev->dev_addr, addr->sa_data);

	return 0;
	}

	static int dsa_slave_ioctl(struct net_device dev, struct ifreq ifr, int cmd)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	if (p->phy != NULL)
	return phy_mii_ioctl(p->phy, ifr, cmd);

	return -EOPNOTSUPP;
	}

	/* Return a bitmask of all ports being currently bridged within a given bridge
	* device. Note that on leave, the mask will still return the bitmask of ports
	* currently bridged, prior to port removal, and this is exactly what we want.
	*/
	static u32 dsa_slave_br_port_mask(struct dsa_switch *ds,
	struct net_device *bridge)
	{
	struct dsa_slave_priv *p;
	unsigned int port;
	u32 mask = 0;

	for (port = 0; port < DSA_MAX_PORTS; port++) {
	if (!dsa_is_port_initialized(ds, port))
	continue;

	p = netdev_priv(ds->ports[port]);

	if (ds->ports[port]->priv_flags & IFF_BRIDGE_PORT &&
	p->bridge_dev == bridge)
	mask \|= 1 << port;
	}

	return mask;
	}

	static int dsa_slave_stp_update(struct net_device *dev, u8 state)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret = -EOPNOTSUPP;

	if (ds->drv->port_stp_update)
	ret = ds->drv->port_stp_update(ds, p->port, state);

	return ret;
	}

	static int dsa_slave_bridge_port_join(struct net_device *dev,
	struct net_device *br)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret = -EOPNOTSUPP;

	p->bridge_dev = br;

	if (ds->drv->port_join_bridge)
	ret = ds->drv->port_join_bridge(ds, p->port,
	dsa_slave_br_port_mask(ds, br));

	return ret;
	}

	static int dsa_slave_bridge_port_leave(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret = -EOPNOTSUPP;


	if (ds->drv->port_leave_bridge)
	ret = ds->drv->port_leave_bridge(ds, p->port,
	dsa_slave_br_port_mask(ds, p->bridge_dev));

	p->bridge_dev = NULL;

	/* Port left the bridge, put in BR_STATE_DISABLED by the bridge layer,
	* so allow it to be in BR_STATE_FORWARDING to be kept functional
	*/
	dsa_slave_stp_update(dev, BR_STATE_FORWARDING);

	return ret;
	}

	static int dsa_slave_parent_id_get(struct net_device *dev,
	struct netdev_phys_item_id *psid)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	psid->id_len = sizeof(ds->index);
	memcpy(&psid->id, &ds->index, psid->id_len);

	return 0;
	}

	static netdev_tx_t dsa_slave_xmit(struct sk_buff skb, struct net_device dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	return p->xmit(skb, dev);
	}

	static netdev_tx_t dsa_slave_notag_xmit(struct sk_buff *skb,
	struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	skb->dev = p->parent->dst->master_netdev;
	dev_queue_xmit(skb);

	return NETDEV_TX_OK;
	}


	/* ethtool operations *******************************************************/
	static int
	dsa_slave_get_settings(struct net_device dev, struct ethtool_cmd cmd)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	int err;

	err = -EOPNOTSUPP;
	if (p->phy != NULL) {
	err = phy_read_status(p->phy);
	if (err == 0)
	err = phy_ethtool_gset(p->phy, cmd);
	}

	return err;
	}

	static int
	dsa_slave_set_settings(struct net_device dev, struct ethtool_cmd cmd)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	if (p->phy != NULL)
	return phy_ethtool_sset(p->phy, cmd);

	return -EOPNOTSUPP;
	}

	static void dsa_slave_get_drvinfo(struct net_device *dev,
	struct ethtool_drvinfo *drvinfo)
	{
	strlcpy(drvinfo->driver, "dsa", sizeof(drvinfo->driver));
	strlcpy(drvinfo->version, dsa_driver_version, sizeof(drvinfo->version));
	strlcpy(drvinfo->fw_version, "N/A", sizeof(drvinfo->fw_version));
	strlcpy(drvinfo->bus_info, "platform", sizeof(drvinfo->bus_info));
	}

	static int dsa_slave_get_regs_len(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->get_regs_len)
	return ds->drv->get_regs_len(ds, p->port);

	return -EOPNOTSUPP;
	}

	static void
	dsa_slave_get_regs(struct net_device dev, struct ethtool_regs regs, void *_p)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->get_regs)
	ds->drv->get_regs(ds, p->port, regs, _p);
	}

	static int dsa_slave_nway_reset(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	if (p->phy != NULL)
	return genphy_restart_aneg(p->phy);

	return -EOPNOTSUPP;
	}

	static u32 dsa_slave_get_link(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);

	if (p->phy != NULL) {
	genphy_update_link(p->phy);
	return p->phy->link;
	}

	return -EOPNOTSUPP;
	}

	static int dsa_slave_get_eeprom_len(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->pd->eeprom_len)
	return ds->pd->eeprom_len;

	if (ds->drv->get_eeprom_len)
	return ds->drv->get_eeprom_len(ds);

	return 0;
	}

	static int dsa_slave_get_eeprom(struct net_device *dev,
	struct ethtool_eeprom eeprom, u8 data)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->get_eeprom)
	return ds->drv->get_eeprom(ds, eeprom, data);

	return -EOPNOTSUPP;
	}

	static int dsa_slave_set_eeprom(struct net_device *dev,
	struct ethtool_eeprom eeprom, u8 data)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->set_eeprom)
	return ds->drv->set_eeprom(ds, eeprom, data);

	return -EOPNOTSUPP;
	}

	static void dsa_slave_get_strings(struct net_device *dev,
	uint32_t stringset, uint8_t *data)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (stringset == ETH_SS_STATS) {
	int len = ETH_GSTRING_LEN;

	strncpy(data, "tx_packets", len);
	strncpy(data + len, "tx_bytes", len);
	strncpy(data + 2 * len, "rx_packets", len);
	strncpy(data + 3 * len, "rx_bytes", len);
	if (ds->drv->get_strings != NULL)
	ds->drv->get_strings(ds, p->port, data + 4 * len);
	}
	}

	static void dsa_slave_get_ethtool_stats(struct net_device *dev,
	struct ethtool_stats *stats,
	uint64_t *data)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	data[0] = p->dev->stats.tx_packets;
	data[1] = p->dev->stats.tx_bytes;
	data[2] = p->dev->stats.rx_packets;
	data[3] = p->dev->stats.rx_bytes;
	if (ds->drv->get_ethtool_stats != NULL)
	ds->drv->get_ethtool_stats(ds, p->port, data + 4);
	}

	static int dsa_slave_get_sset_count(struct net_device *dev, int sset)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (sset == ETH_SS_STATS) {
	int count;

	count = 4;
	if (ds->drv->get_sset_count != NULL)
	count += ds->drv->get_sset_count(ds);

	return count;
	}

	return -EOPNOTSUPP;
	}

	static void dsa_slave_get_wol(struct net_device dev, struct ethtool_wolinfo w)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->get_wol)
	ds->drv->get_wol(ds, p->port, w);
	}

	static int dsa_slave_set_wol(struct net_device dev, struct ethtool_wolinfo w)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret = -EOPNOTSUPP;

	if (ds->drv->set_wol)
	ret = ds->drv->set_wol(ds, p->port, w);

	return ret;
	}

	static int dsa_slave_set_eee(struct net_device dev, struct ethtool_eee e)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret;

	if (!ds->drv->set_eee)
	return -EOPNOTSUPP;

	ret = ds->drv->set_eee(ds, p->port, p->phy, e);
	if (ret)
	return ret;

	if (p->phy)
	ret = phy_ethtool_set_eee(p->phy, e);

	return ret;
	}

	static int dsa_slave_get_eee(struct net_device dev, struct ethtool_eee e)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	int ret;

	if (!ds->drv->get_eee)
	return -EOPNOTSUPP;

	ret = ds->drv->get_eee(ds, p->port, e);
	if (ret)
	return ret;

	if (p->phy)
	ret = phy_ethtool_get_eee(p->phy, e);

	return ret;
	}

	static const struct ethtool_ops dsa_slave_ethtool_ops = {
	.get_settings = dsa_slave_get_settings,
	.set_settings = dsa_slave_set_settings,
	.get_drvinfo = dsa_slave_get_drvinfo,
	.get_regs_len = dsa_slave_get_regs_len,
	.get_regs = dsa_slave_get_regs,
	.nway_reset = dsa_slave_nway_reset,
	.get_link = dsa_slave_get_link,
	.get_eeprom_len = dsa_slave_get_eeprom_len,
	.get_eeprom = dsa_slave_get_eeprom,
	.set_eeprom = dsa_slave_set_eeprom,
	.get_strings = dsa_slave_get_strings,
	.get_ethtool_stats = dsa_slave_get_ethtool_stats,
	.get_sset_count = dsa_slave_get_sset_count,
	.set_wol = dsa_slave_set_wol,
	.get_wol = dsa_slave_get_wol,
	.set_eee = dsa_slave_set_eee,
	.get_eee = dsa_slave_get_eee,
	};

	static const struct net_device_ops dsa_slave_netdev_ops = {
	.ndo_init = dsa_slave_init,
	.ndo_open = dsa_slave_open,
	.ndo_stop = dsa_slave_close,
	.ndo_start_xmit = dsa_slave_xmit,
	.ndo_change_rx_flags = dsa_slave_change_rx_flags,
	.ndo_set_rx_mode = dsa_slave_set_rx_mode,
	.ndo_set_mac_address = dsa_slave_set_mac_address,
	.ndo_do_ioctl = dsa_slave_ioctl,
	};

	static const struct swdev_ops dsa_slave_swdev_ops = {
	.swdev_parent_id_get = dsa_slave_parent_id_get,
	.swdev_port_stp_update = dsa_slave_stp_update,
	};

	static void dsa_slave_adjust_link(struct net_device *dev)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;
	unsigned int status_changed = 0;

	if (p->old_link != p->phy->link) {
	status_changed = 1;
	p->old_link = p->phy->link;
	}

	if (p->old_duplex != p->phy->duplex) {
	status_changed = 1;
	p->old_duplex = p->phy->duplex;
	}

	if (p->old_pause != p->phy->pause) {
	status_changed = 1;
	p->old_pause = p->phy->pause;
	}

	if (ds->drv->adjust_link && status_changed)
	ds->drv->adjust_link(ds, p->port, p->phy);

	if (status_changed)
	phy_print_status(p->phy);
	}

	static int dsa_slave_fixed_link_update(struct net_device *dev,
	struct fixed_phy_status *status)
	{
	struct dsa_slave_priv *p = netdev_priv(dev);
	struct dsa_switch *ds = p->parent;

	if (ds->drv->fixed_link_update)
	ds->drv->fixed_link_update(ds, p->port, status);

	return 0;
	}

	/* slave device setup *******************************************************/
	static int dsa_slave_phy_connect(struct dsa_slave_priv *p,
	struct net_device *slave_dev,
	int addr)
	{
	struct dsa_switch *ds = p->parent;

	p->phy = ds->slave_mii_bus->phy_map[addr];
	if (!p->phy)
	return -ENODEV;

	/* Use already configured phy mode */
	p->phy_interface = p->phy->interface;
	phy_connect_direct(slave_dev, p->phy, dsa_slave_adjust_link,
	p->phy_interface);

	return 0;
	}

	static int dsa_slave_phy_setup(struct dsa_slave_priv *p,
	struct net_device *slave_dev)
	{
	struct dsa_switch *ds = p->parent;
	struct dsa_chip_data *cd = ds->pd;
	struct device_node phy_dn, port_dn;
	bool phy_is_fixed = false;
	u32 phy_flags = 0;
	int mode, ret;

	port_dn = cd->port_dn[p->port];
	mode = of_get_phy_mode(port_dn);
	if (mode < 0)
	mode = PHY_INTERFACE_MODE_NA;
	p->phy_interface = mode;

	phy_dn = of_parse_phandle(port_dn, "phy-handle", 0);
	if (of_phy_is_fixed_link(port_dn)) {
	/* In the case of a fixed PHY, the DT node associated
	* to the fixed PHY is the Port DT node
	*/
	ret = of_phy_register_fixed_link(port_dn);
	if (ret) {
	netdev_err(slave_dev, "failed to register fixed PHY\n");
	return ret;
	}
	phy_is_fixed = true;
	phy_dn = port_dn;
	}

	if (ds->drv->get_phy_flags)
	phy_flags = ds->drv->get_phy_flags(ds, p->port);

	if (phy_dn) {
	ret = of_mdio_parse_addr(&slave_dev->dev, phy_dn);
	/* If this PHY address is part of phys_mii_mask, which means
	* that we need to divert reads and writes to/from it, then we
	* want to bind this device using the slave MII bus created by
	* DSA to make that happen.
	*/
	if (!phy_is_fixed && ret >= 0 &&
	(ds->phys_mii_mask & (1 << ret))) {
	ret = dsa_slave_phy_connect(p, slave_dev, ret);
	if (ret)
	return ret;
	} else {
	p->phy = of_phy_connect(slave_dev, phy_dn,
	dsa_slave_adjust_link,
	phy_flags,
	p->phy_interface);
	}
	}

	if (p->phy && phy_is_fixed)
	fixed_phy_set_link_update(p->phy, dsa_slave_fixed_link_update);

	/* We could not connect to a designated PHY, so use the switch internal
	* MDIO bus instead
	*/
	if (!p->phy) {
	ret = dsa_slave_phy_connect(p, slave_dev, p->port);
	if (ret)
	return ret;
	} else {
	netdev_info(slave_dev, "attached PHY at address %d [%s]\n",
	p->phy->addr, p->phy->drv->name);
	}

	return 0;
	}

	int dsa_slave_suspend(struct net_device *slave_dev)
	{
	struct dsa_slave_priv *p = netdev_priv(slave_dev);

	netif_device_detach(slave_dev);

	if (p->phy) {
	phy_stop(p->phy);
	p->old_pause = -1;
	p->old_link = -1;
	p->old_duplex = -1;
	phy_suspend(p->phy);
	}

	return 0;
	}

	int dsa_slave_resume(struct net_device *slave_dev)
	{
	struct dsa_slave_priv *p = netdev_priv(slave_dev);

	netif_device_attach(slave_dev);

	if (p->phy) {
	phy_resume(p->phy);
	phy_start(p->phy);
	}

	return 0;
	}

	int dsa_slave_create(struct dsa_switch ds, struct device parent,
	int port, char *name)
	{
	struct net_device *master = ds->dst->master_netdev;
	struct net_device *slave_dev;
	struct dsa_slave_priv *p;
	int ret;

	slave_dev = alloc_netdev(sizeof(struct dsa_slave_priv), name,
	NET_NAME_UNKNOWN, ether_setup);
	if (slave_dev == NULL)
	return -ENOMEM;

	slave_dev->features = master->vlan_features;
	slave_dev->ethtool_ops = &dsa_slave_ethtool_ops;
	eth_hw_addr_inherit(slave_dev, master);
	slave_dev->tx_queue_len = 0;
	slave_dev->netdev_ops = &dsa_slave_netdev_ops;
	slave_dev->swdev_ops = &dsa_slave_swdev_ops;

	SET_NETDEV_DEV(slave_dev, parent);
	slave_dev->dev.of_node = ds->pd->port_dn[port];
	slave_dev->vlan_features = master->vlan_features;

	p = netdev_priv(slave_dev);
	p->dev = slave_dev;
	p->parent = ds;
	p->port = port;

	switch (ds->dst->tag_protocol) {
	#ifdef CONFIG_NET_DSA_TAG_DSA
	case DSA_TAG_PROTO_DSA:
	p->xmit = dsa_netdev_ops.xmit;
	break;
	#endif
	#ifdef CONFIG_NET_DSA_TAG_EDSA
	case DSA_TAG_PROTO_EDSA:
	p->xmit = edsa_netdev_ops.xmit;
	break;
	#endif
	#ifdef CONFIG_NET_DSA_TAG_TRAILER
	case DSA_TAG_PROTO_TRAILER:
	p->xmit = trailer_netdev_ops.xmit;
	break;
	#endif
	#ifdef CONFIG_NET_DSA_TAG_BRCM
	case DSA_TAG_PROTO_BRCM:
	p->xmit = brcm_netdev_ops.xmit;
	break;
	#endif
	default:
	p->xmit = dsa_slave_notag_xmit;
	break;
	}

	p->old_pause = -1;
	p->old_link = -1;
	p->old_duplex = -1;

	ret = dsa_slave_phy_setup(p, slave_dev);
	if (ret) {
	free_netdev(slave_dev);
	return ret;
	}

	ds->ports[port] = slave_dev;
	ret = register_netdev(slave_dev);
	if (ret) {
	netdev_err(master, "error %d registering interface %s\n",
	ret, slave_dev->name);
	phy_disconnect(p->phy);
	ds->ports[port] = NULL;
	free_netdev(slave_dev);
	return ret;
	}

	netif_carrier_off(slave_dev);

	return 0;
	}

	static bool dsa_slave_dev_check(struct net_device *dev)
	{
	return dev->netdev_ops == &dsa_slave_netdev_ops;
	}

	static int dsa_slave_master_changed(struct net_device *dev)
	{
	struct net_device *master = netdev_master_upper_dev_get(dev);
	int err = 0;

	if (master && master->rtnl_link_ops &&
	!strcmp(master->rtnl_link_ops->kind, "bridge"))
	err = dsa_slave_bridge_port_join(dev, master);
	else
	err = dsa_slave_bridge_port_leave(dev);

	return err;
	}

	int dsa_slave_netdevice_event(struct notifier_block *unused,
	unsigned long event, void *ptr)
	{
	struct net_device *dev;
	int err = 0;

	switch (event) {
	case NETDEV_CHANGEUPPER:
	dev = netdev_notifier_info_to_dev(ptr);
	if (!dsa_slave_dev_check(dev))
	goto out;

	err = dsa_slave_master_changed(dev);
	if (err)
	netdev_warn(dev, "failed to reflect master change\n");

	break;
	}

	out:
	return NOTIFY_DONE;
	}