/*
   * net/dsa/dsa.c - Hardware switch handling

   * Copyright (c) 2008-2009 Marvell Semiconductor

   * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>

   *
   * 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/device.h>

  #include <linux/list.h>

  #include <linux/platform_device.h>

  #include <linux/slab.h>

  #include <linux/module.h>

  #include <linux/of.h>
  #include <linux/of_mdio.h>
  #include <linux/of_platform.h>

  #include <linux/of_net.h>

  #include <linux/of_gpio.h>

  #include <linux/netdevice.h>

  #include <linux/sysfs.h>

  #include <linux/phy_fixed.h>

  #include <linux/gpio/consumer.h>

  #include <linux/etherdevice.h>

  #include "dsa_priv.h"

  static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
  					    struct net_device *dev)
  {
  	/* Just return the original SKB */
  	return skb;
  }
  
  static const struct dsa_device_ops none_ops = {
  	.xmit	= dsa_slave_notag_xmit,
  	.rcv	= NULL,
  };
  
  const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {

  #ifdef CONFIG_NET_DSA_TAG_BRCM
  	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
  #endif

  #ifdef CONFIG_NET_DSA_TAG_DSA
  	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
  #endif
  #ifdef CONFIG_NET_DSA_TAG_EDSA
  	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
  #endif

  #ifdef CONFIG_NET_DSA_TAG_KSZ
  	[DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
  #endif

  #ifdef CONFIG_NET_DSA_TAG_LAN9303
  	[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,

  #endif

  #ifdef CONFIG_NET_DSA_TAG_MTK
  	[DSA_TAG_PROTO_MTK] = &mtk_netdev_ops,

  #endif

  #ifdef CONFIG_NET_DSA_TAG_QCA
  	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
  #endif

  #ifdef CONFIG_NET_DSA_TAG_TRAILER
  	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,

  #endif

  	[DSA_TAG_PROTO_NONE] = &none_ops,
  };

  int dsa_cpu_dsa_setup(struct dsa_port *port)

  {

  	struct device_node *port_dn = port->dn;
  	struct dsa_switch *ds = port->ds;

  	struct phy_device *phydev;

  	int ret, mode;
  
  	if (of_phy_is_fixed_link(port_dn)) {
  		ret = of_phy_register_fixed_link(port_dn);
  		if (ret) {

  			dev_err(ds->dev, "failed to register fixed PHY
  ");

  			return ret;
  		}
  		phydev = of_phy_find_device(port_dn);
  
  		mode = of_get_phy_mode(port_dn);
  		if (mode < 0)
  			mode = PHY_INTERFACE_MODE_NA;
  		phydev->interface = mode;
  
  		genphy_config_init(phydev);
  		genphy_read_status(phydev);

  		if (ds->ops->adjust_link)

  			ds->ops->adjust_link(ds, port->index, phydev);

  
  		put_device(&phydev->mdio.dev);

  	}
  
  	return 0;
  }

  const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
  {
  	const struct dsa_device_ops *ops;
  
  	if (tag_protocol >= DSA_TAG_LAST)
  		return ERR_PTR(-EINVAL);
  	ops = dsa_device_ops[tag_protocol];
  
  	if (!ops)
  		return ERR_PTR(-ENOPROTOOPT);
  
  	return ops;
  }

  int dsa_cpu_port_ethtool_setup(struct dsa_port *cpu_dp)

  {

  	struct dsa_switch *ds = cpu_dp->ds;

  	struct net_device *master;
  	struct ethtool_ops *cpu_ops;

  	master = cpu_dp->netdev;

  	cpu_ops = devm_kzalloc(ds->dev, sizeof(*cpu_ops), GFP_KERNEL);
  	if (!cpu_ops)
  		return -ENOMEM;

  	memcpy(&cpu_dp->ethtool_ops, master->ethtool_ops,

  	       sizeof(struct ethtool_ops));

  	cpu_dp->orig_ethtool_ops = master->ethtool_ops;
  	memcpy(cpu_ops, &cpu_dp->ethtool_ops,

  	       sizeof(struct ethtool_ops));
  	dsa_cpu_port_ethtool_init(cpu_ops);
  	master->ethtool_ops = cpu_ops;
  
  	return 0;
  }

  void dsa_cpu_port_ethtool_restore(struct dsa_port *cpu_dp)

  {

  	cpu_dp->netdev->ethtool_ops = cpu_dp->orig_ethtool_ops;

  }

  void dsa_cpu_dsa_destroy(struct dsa_port *port)

  {

  	struct device_node *port_dn = port->dn;

  	if (of_phy_is_fixed_link(port_dn))
  		of_phy_deregister_fixed_link(port_dn);

  }

  static int dev_is_class(struct device *dev, void *class)
  {
  	if (dev->class != NULL && !strcmp(dev->class->name, class))
  		return 1;
  
  	return 0;
  }
  
  static struct device *dev_find_class(struct device *parent, char *class)
  {
  	if (dev_is_class(parent, class)) {
  		get_device(parent);
  		return parent;
  	}
  
  	return device_find_child(parent, class, dev_is_class);
  }

  struct net_device *dsa_dev_to_net_device(struct device *dev)

  {
  	struct device *d;
  
  	d = dev_find_class(dev, "net");
  	if (d != NULL) {
  		struct net_device *nd;
  
  		nd = to_net_dev(d);
  		dev_hold(nd);
  		put_device(d);
  
  		return nd;
  	}
  
  	return NULL;
  }

  EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);

  static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,

  			  struct packet_type *pt, struct net_device *unused)

  {
  	struct dsa_switch_tree *dst = dev->dsa_ptr;

  	struct sk_buff *nskb = NULL;

  	struct pcpu_sw_netstats *s;

  	struct dsa_slave_priv *p;

  
  	if (unlikely(dst == NULL)) {
  		kfree_skb(skb);
  		return 0;
  	}

  	skb = skb_unshare(skb, GFP_ATOMIC);
  	if (!skb)
  		return 0;

  	nskb = dst->rcv(skb, dev, pt);

  	if (!nskb) {
  		kfree_skb(skb);
  		return 0;
  	}
  
  	skb = nskb;

  	p = netdev_priv(skb->dev);

  	skb_push(skb, ETH_HLEN);
  	skb->pkt_type = PACKET_HOST;
  	skb->protocol = eth_type_trans(skb, skb->dev);

  	s = this_cpu_ptr(p->stats64);
  	u64_stats_update_begin(&s->syncp);
  	s->rx_packets++;
  	s->rx_bytes += skb->len;
  	u64_stats_update_end(&s->syncp);

  
  	netif_receive_skb(skb);
  
  	return 0;

  }

  #ifdef CONFIG_PM_SLEEP

  static bool dsa_is_port_initialized(struct dsa_switch *ds, int p)
  {
  	return ds->enabled_port_mask & (1 << p) && ds->ports[p].netdev;
  }

  int dsa_switch_suspend(struct dsa_switch *ds)
  {
  	int i, ret = 0;
  
  	/* Suspend slave network devices */
  	for (i = 0; i < ds->num_ports; i++) {
  		if (!dsa_is_port_initialized(ds, i))
  			continue;
  
  		ret = dsa_slave_suspend(ds->ports[i].netdev);
  		if (ret)
  			return ret;
  	}
  
  	if (ds->ops->suspend)
  		ret = ds->ops->suspend(ds);
  
  	return ret;
  }
  EXPORT_SYMBOL_GPL(dsa_switch_suspend);
  
  int dsa_switch_resume(struct dsa_switch *ds)
  {
  	int i, ret = 0;
  
  	if (ds->ops->resume)
  		ret = ds->ops->resume(ds);
  
  	if (ret)
  		return ret;
  
  	/* Resume slave network devices */
  	for (i = 0; i < ds->num_ports; i++) {
  		if (!dsa_is_port_initialized(ds, i))
  			continue;
  
  		ret = dsa_slave_resume(ds->ports[i].netdev);
  		if (ret)
  			return ret;
  	}
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(dsa_switch_resume);
  #endif

  static struct packet_type dsa_pack_type __read_mostly = {

  	.type	= cpu_to_be16(ETH_P_XDSA),
  	.func	= dsa_switch_rcv,
  };

  static struct workqueue_struct *dsa_owq;
  
  bool dsa_schedule_work(struct work_struct *work)
  {
  	return queue_work(dsa_owq, work);
  }

  static int __init dsa_init_module(void)
  {

  	int rc;

  	dsa_owq = alloc_ordered_workqueue("dsa_ordered",
  					  WQ_MEM_RECLAIM);
  	if (!dsa_owq)
  		return -ENOMEM;

  	rc = dsa_slave_register_notifier();
  	if (rc)
  		return rc;

  	rc = dsa_legacy_register();

  	if (rc)
  		return rc;

  	dev_add_pack(&dsa_pack_type);

  	return 0;

  }
  module_init(dsa_init_module);
  
  static void __exit dsa_cleanup_module(void)
  {

  	dsa_slave_unregister_notifier();

  	dev_remove_pack(&dsa_pack_type);

  	dsa_legacy_unregister();

  	destroy_workqueue(dsa_owq);

  }
  module_exit(dsa_cleanup_module);

  MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");

  MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS("platform:dsa");