v4.19.13 snapshot.
diff --git a/net/dsa/legacy.c b/net/dsa/legacy.c
new file mode 100644
index 0000000..42a7b85
--- /dev/null
+++ b/net/dsa/legacy.c
@@ -0,0 +1,748 @@
+/*
+ * net/dsa/legacy.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/netdevice.h>
+#include <linux/sysfs.h>
+#include <linux/phy_fixed.h>
+#include <linux/etherdevice.h>
+
+#include "dsa_priv.h"
+
+/* switch driver registration ***********************************************/
+static DEFINE_MUTEX(dsa_switch_drivers_mutex);
+static LIST_HEAD(dsa_switch_drivers);
+
+void register_switch_driver(struct dsa_switch_driver *drv)
+{
+	mutex_lock(&dsa_switch_drivers_mutex);
+	list_add_tail(&drv->list, &dsa_switch_drivers);
+	mutex_unlock(&dsa_switch_drivers_mutex);
+}
+EXPORT_SYMBOL_GPL(register_switch_driver);
+
+void unregister_switch_driver(struct dsa_switch_driver *drv)
+{
+	mutex_lock(&dsa_switch_drivers_mutex);
+	list_del_init(&drv->list);
+	mutex_unlock(&dsa_switch_drivers_mutex);
+}
+EXPORT_SYMBOL_GPL(unregister_switch_driver);
+
+static const struct dsa_switch_ops *
+dsa_switch_probe(struct device *parent, struct device *host_dev, int sw_addr,
+		 const char **_name, void **priv)
+{
+	const struct dsa_switch_ops *ret;
+	struct list_head *list;
+	const char *name;
+
+	ret = NULL;
+	name = NULL;
+
+	mutex_lock(&dsa_switch_drivers_mutex);
+	list_for_each(list, &dsa_switch_drivers) {
+		const struct dsa_switch_ops *ops;
+		struct dsa_switch_driver *drv;
+
+		drv = list_entry(list, struct dsa_switch_driver, list);
+		ops = drv->ops;
+
+		name = ops->probe(parent, host_dev, sw_addr, priv);
+		if (name != NULL) {
+			ret = ops;
+			break;
+		}
+	}
+	mutex_unlock(&dsa_switch_drivers_mutex);
+
+	*_name = name;
+
+	return ret;
+}
+
+/* basic switch operations **************************************************/
+static int dsa_cpu_dsa_setups(struct dsa_switch *ds)
+{
+	int ret, port;
+
+	for (port = 0; port < ds->num_ports; port++) {
+		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
+			continue;
+
+		ret = dsa_port_link_register_of(&ds->ports[port]);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static int dsa_switch_setup_one(struct dsa_switch *ds,
+				struct net_device *master)
+{
+	const struct dsa_switch_ops *ops = ds->ops;
+	struct dsa_switch_tree *dst = ds->dst;
+	struct dsa_chip_data *cd = ds->cd;
+	bool valid_name_found = false;
+	int index = ds->index;
+	struct dsa_port *dp;
+	int i, ret;
+
+	/*
+	 * Validate supplied switch configuration.
+	 */
+	for (i = 0; i < ds->num_ports; i++) {
+		char *name;
+
+		dp = &ds->ports[i];
+
+		name = cd->port_names[i];
+		if (name == NULL)
+			continue;
+		dp->name = name;
+
+		if (!strcmp(name, "cpu")) {
+			if (dst->cpu_dp) {
+				netdev_err(master,
+					   "multiple cpu ports?!\n");
+				return -EINVAL;
+			}
+			dst->cpu_dp = &ds->ports[i];
+			dst->cpu_dp->master = master;
+			dp->type = DSA_PORT_TYPE_CPU;
+		} else if (!strcmp(name, "dsa")) {
+			dp->type = DSA_PORT_TYPE_DSA;
+		} else {
+			dp->type = DSA_PORT_TYPE_USER;
+		}
+		valid_name_found = true;
+	}
+
+	if (!valid_name_found && i == ds->num_ports)
+		return -EINVAL;
+
+	/* Make the built-in MII bus mask match the number of ports,
+	 * switch drivers can override this later
+	 */
+	ds->phys_mii_mask |= dsa_user_ports(ds);
+
+	/*
+	 * If the CPU connects to this switch, set the switch tree
+	 * tagging protocol to the preferred tagging format of this
+	 * switch.
+	 */
+	if (dst->cpu_dp->ds == ds) {
+		const struct dsa_device_ops *tag_ops;
+		enum dsa_tag_protocol tag_protocol;
+
+		tag_protocol = ops->get_tag_protocol(ds, dst->cpu_dp->index);
+		tag_ops = dsa_resolve_tag_protocol(tag_protocol);
+		if (IS_ERR(tag_ops))
+			return PTR_ERR(tag_ops);
+
+		dst->cpu_dp->tag_ops = tag_ops;
+
+		/* Few copies for faster access in master receive hot path */
+		dst->cpu_dp->rcv = dst->cpu_dp->tag_ops->rcv;
+		dst->cpu_dp->dst = dst;
+	}
+
+	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
+
+	/*
+	 * Do basic register setup.
+	 */
+	ret = ops->setup(ds);
+	if (ret < 0)
+		return ret;
+
+	ret = dsa_switch_register_notifier(ds);
+	if (ret)
+		return ret;
+
+	if (!ds->slave_mii_bus && ops->phy_read) {
+		ds->slave_mii_bus = devm_mdiobus_alloc(ds->dev);
+		if (!ds->slave_mii_bus)
+			return -ENOMEM;
+		dsa_slave_mii_bus_init(ds);
+
+		ret = mdiobus_register(ds->slave_mii_bus);
+		if (ret < 0)
+			return ret;
+	}
+
+	/*
+	 * Create network devices for physical switch ports.
+	 */
+	for (i = 0; i < ds->num_ports; i++) {
+		ds->ports[i].dn = cd->port_dn[i];
+		ds->ports[i].cpu_dp = dst->cpu_dp;
+
+		if (!dsa_is_user_port(ds, i))
+			continue;
+
+		ret = dsa_slave_create(&ds->ports[i]);
+		if (ret < 0)
+			netdev_err(master, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
+				   index, i, cd->port_names[i], ret);
+	}
+
+	/* Perform configuration of the CPU and DSA ports */
+	ret = dsa_cpu_dsa_setups(ds);
+	if (ret < 0)
+		netdev_err(master, "[%d] : can't configure CPU and DSA ports\n",
+			   index);
+
+	return 0;
+}
+
+static struct dsa_switch *
+dsa_switch_setup(struct dsa_switch_tree *dst, struct net_device *master,
+		 int index, struct device *parent, struct device *host_dev)
+{
+	struct dsa_chip_data *cd = dst->pd->chip + index;
+	const struct dsa_switch_ops *ops;
+	struct dsa_switch *ds;
+	int ret;
+	const char *name;
+	void *priv;
+
+	/*
+	 * Probe for switch model.
+	 */
+	ops = dsa_switch_probe(parent, host_dev, cd->sw_addr, &name, &priv);
+	if (!ops) {
+		netdev_err(master, "[%d]: could not detect attached switch\n",
+			   index);
+		return ERR_PTR(-EINVAL);
+	}
+	netdev_info(master, "[%d]: detected a %s switch\n",
+		    index, name);
+
+
+	/*
+	 * Allocate and initialise switch state.
+	 */
+	ds = dsa_switch_alloc(parent, DSA_MAX_PORTS);
+	if (!ds)
+		return ERR_PTR(-ENOMEM);
+
+	ds->dst = dst;
+	ds->index = index;
+	ds->cd = cd;
+	ds->ops = ops;
+	ds->priv = priv;
+
+	ret = dsa_switch_setup_one(ds, master);
+	if (ret)
+		return ERR_PTR(ret);
+
+	return ds;
+}
+
+static void dsa_switch_destroy(struct dsa_switch *ds)
+{
+	int port;
+
+	/* Destroy network devices for physical switch ports. */
+	for (port = 0; port < ds->num_ports; port++) {
+		if (!dsa_is_user_port(ds, port))
+			continue;
+
+		if (!ds->ports[port].slave)
+			continue;
+
+		dsa_slave_destroy(ds->ports[port].slave);
+	}
+
+	/* Disable configuration of the CPU and DSA ports */
+	for (port = 0; port < ds->num_ports; port++) {
+		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
+			continue;
+		dsa_port_link_unregister_of(&ds->ports[port]);
+	}
+
+	if (ds->slave_mii_bus && ds->ops->phy_read)
+		mdiobus_unregister(ds->slave_mii_bus);
+
+	dsa_switch_unregister_notifier(ds);
+}
+
+/* platform driver init and cleanup *****************************************/
+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 mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
+{
+	struct device *d;
+
+	d = dev_find_class(dev, "mdio_bus");
+	if (d != NULL) {
+		struct mii_bus *bus;
+
+		bus = to_mii_bus(d);
+		put_device(d);
+
+		return bus;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
+
+#ifdef CONFIG_OF
+static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
+					struct dsa_chip_data *cd,
+					int chip_index, int port_index,
+					struct device_node *link)
+{
+	const __be32 *reg;
+	int link_sw_addr;
+	struct device_node *parent_sw;
+	int len;
+
+	parent_sw = of_get_parent(link);
+	if (!parent_sw)
+		return -EINVAL;
+
+	reg = of_get_property(parent_sw, "reg", &len);
+	if (!reg || (len != sizeof(*reg) * 2))
+		return -EINVAL;
+
+	/*
+	 * Get the destination switch number from the second field of its 'reg'
+	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
+	 */
+	link_sw_addr = be32_to_cpup(reg + 1);
+
+	if (link_sw_addr >= pd->nr_chips)
+		return -EINVAL;
+
+	cd->rtable[link_sw_addr] = port_index;
+
+	return 0;
+}
+
+static int dsa_of_probe_links(struct dsa_platform_data *pd,
+			      struct dsa_chip_data *cd,
+			      int chip_index, int port_index,
+			      struct device_node *port,
+			      const char *port_name)
+{
+	struct device_node *link;
+	int link_index;
+	int ret;
+
+	for (link_index = 0;; link_index++) {
+		link = of_parse_phandle(port, "link", link_index);
+		if (!link)
+			break;
+
+		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
+			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
+							 port_index, link);
+			if (ret)
+				return ret;
+		}
+	}
+	return 0;
+}
+
+static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
+{
+	int i;
+	int port_index;
+
+	for (i = 0; i < pd->nr_chips; i++) {
+		port_index = 0;
+		while (port_index < DSA_MAX_PORTS) {
+			kfree(pd->chip[i].port_names[port_index]);
+			port_index++;
+		}
+
+		/* Drop our reference to the MDIO bus device */
+		if (pd->chip[i].host_dev)
+			put_device(pd->chip[i].host_dev);
+	}
+	kfree(pd->chip);
+}
+
+static int dsa_of_probe(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *child, *mdio, *ethernet, *port;
+	struct mii_bus *mdio_bus, *mdio_bus_switch;
+	struct net_device *ethernet_dev;
+	struct dsa_platform_data *pd;
+	struct dsa_chip_data *cd;
+	const char *port_name;
+	int chip_index, port_index;
+	const unsigned int *sw_addr, *port_reg;
+	u32 eeprom_len;
+	int ret;
+
+	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
+	if (!mdio)
+		return -EINVAL;
+
+	mdio_bus = of_mdio_find_bus(mdio);
+	if (!mdio_bus)
+		return -EPROBE_DEFER;
+
+	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
+	if (!ethernet) {
+		ret = -EINVAL;
+		goto out_put_mdio;
+	}
+
+	ethernet_dev = of_find_net_device_by_node(ethernet);
+	if (!ethernet_dev) {
+		ret = -EPROBE_DEFER;
+		goto out_put_mdio;
+	}
+
+	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
+	if (!pd) {
+		ret = -ENOMEM;
+		goto out_put_ethernet;
+	}
+
+	dev->platform_data = pd;
+	pd->of_netdev = ethernet_dev;
+	pd->nr_chips = of_get_available_child_count(np);
+	if (pd->nr_chips > DSA_MAX_SWITCHES)
+		pd->nr_chips = DSA_MAX_SWITCHES;
+
+	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
+			   GFP_KERNEL);
+	if (!pd->chip) {
+		ret = -ENOMEM;
+		goto out_free;
+	}
+
+	chip_index = -1;
+	for_each_available_child_of_node(np, child) {
+		int i;
+
+		chip_index++;
+		cd = &pd->chip[chip_index];
+
+		cd->of_node = child;
+
+		/* Initialize the routing table */
+		for (i = 0; i < DSA_MAX_SWITCHES; ++i)
+			cd->rtable[i] = DSA_RTABLE_NONE;
+
+		/* When assigning the host device, increment its refcount */
+		cd->host_dev = get_device(&mdio_bus->dev);
+
+		sw_addr = of_get_property(child, "reg", NULL);
+		if (!sw_addr)
+			continue;
+
+		cd->sw_addr = be32_to_cpup(sw_addr);
+		if (cd->sw_addr >= PHY_MAX_ADDR)
+			continue;
+
+		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
+			cd->eeprom_len = eeprom_len;
+
+		mdio = of_parse_phandle(child, "mii-bus", 0);
+		if (mdio) {
+			mdio_bus_switch = of_mdio_find_bus(mdio);
+			if (!mdio_bus_switch) {
+				ret = -EPROBE_DEFER;
+				goto out_free_chip;
+			}
+
+			/* Drop the mdio_bus device ref, replacing the host
+			 * device with the mdio_bus_switch device, keeping
+			 * the refcount from of_mdio_find_bus() above.
+			 */
+			put_device(cd->host_dev);
+			cd->host_dev = &mdio_bus_switch->dev;
+		}
+
+		for_each_available_child_of_node(child, port) {
+			port_reg = of_get_property(port, "reg", NULL);
+			if (!port_reg)
+				continue;
+
+			port_index = be32_to_cpup(port_reg);
+			if (port_index >= DSA_MAX_PORTS)
+				break;
+
+			port_name = of_get_property(port, "label", NULL);
+			if (!port_name)
+				continue;
+
+			cd->port_dn[port_index] = port;
+
+			cd->port_names[port_index] = kstrdup(port_name,
+					GFP_KERNEL);
+			if (!cd->port_names[port_index]) {
+				ret = -ENOMEM;
+				goto out_free_chip;
+			}
+
+			ret = dsa_of_probe_links(pd, cd, chip_index,
+						 port_index, port, port_name);
+			if (ret)
+				goto out_free_chip;
+
+		}
+	}
+
+	/* The individual chips hold their own refcount on the mdio bus,
+	 * so drop ours */
+	put_device(&mdio_bus->dev);
+
+	return 0;
+
+out_free_chip:
+	dsa_of_free_platform_data(pd);
+out_free:
+	kfree(pd);
+	dev->platform_data = NULL;
+out_put_ethernet:
+	put_device(&ethernet_dev->dev);
+out_put_mdio:
+	put_device(&mdio_bus->dev);
+	return ret;
+}
+
+static void dsa_of_remove(struct device *dev)
+{
+	struct dsa_platform_data *pd = dev->platform_data;
+
+	if (!dev->of_node)
+		return;
+
+	dsa_of_free_platform_data(pd);
+	put_device(&pd->of_netdev->dev);
+	kfree(pd);
+}
+#else
+static inline int dsa_of_probe(struct device *dev)
+{
+	return 0;
+}
+
+static inline void dsa_of_remove(struct device *dev)
+{
+}
+#endif
+
+static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
+			 struct device *parent, struct dsa_platform_data *pd)
+{
+	int i;
+	unsigned configured = 0;
+
+	dst->pd = pd;
+
+	for (i = 0; i < pd->nr_chips; i++) {
+		struct dsa_switch *ds;
+
+		ds = dsa_switch_setup(dst, dev, i, parent, pd->chip[i].host_dev);
+		if (IS_ERR(ds)) {
+			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
+				   i, PTR_ERR(ds));
+			continue;
+		}
+
+		dst->ds[i] = ds;
+
+		++configured;
+	}
+
+	/*
+	 * If no switch was found, exit cleanly
+	 */
+	if (!configured)
+		return -EPROBE_DEFER;
+
+	return dsa_master_setup(dst->cpu_dp->master, dst->cpu_dp);
+}
+
+static int dsa_probe(struct platform_device *pdev)
+{
+	struct dsa_platform_data *pd = pdev->dev.platform_data;
+	struct net_device *dev;
+	struct dsa_switch_tree *dst;
+	int ret;
+
+	if (pdev->dev.of_node) {
+		ret = dsa_of_probe(&pdev->dev);
+		if (ret)
+			return ret;
+
+		pd = pdev->dev.platform_data;
+	}
+
+	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
+		return -EINVAL;
+
+	if (pd->of_netdev) {
+		dev = pd->of_netdev;
+		dev_hold(dev);
+	} else {
+		dev = dsa_dev_to_net_device(pd->netdev);
+	}
+	if (dev == NULL) {
+		ret = -EPROBE_DEFER;
+		goto out;
+	}
+
+	if (dev->dsa_ptr != NULL) {
+		dev_put(dev);
+		ret = -EEXIST;
+		goto out;
+	}
+
+	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
+	if (dst == NULL) {
+		dev_put(dev);
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	platform_set_drvdata(pdev, dst);
+
+	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
+	if (ret) {
+		dev_put(dev);
+		goto out;
+	}
+
+	return 0;
+
+out:
+	dsa_of_remove(&pdev->dev);
+
+	return ret;
+}
+
+static void dsa_remove_dst(struct dsa_switch_tree *dst)
+{
+	int i;
+
+	dsa_master_teardown(dst->cpu_dp->master);
+
+	for (i = 0; i < dst->pd->nr_chips; i++) {
+		struct dsa_switch *ds = dst->ds[i];
+
+		if (ds)
+			dsa_switch_destroy(ds);
+	}
+
+	dev_put(dst->cpu_dp->master);
+}
+
+static int dsa_remove(struct platform_device *pdev)
+{
+	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
+
+	dsa_remove_dst(dst);
+	dsa_of_remove(&pdev->dev);
+
+	return 0;
+}
+
+static void dsa_shutdown(struct platform_device *pdev)
+{
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int dsa_suspend(struct device *d)
+{
+	struct platform_device *pdev = to_platform_device(d);
+	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
+	int i, ret = 0;
+
+	for (i = 0; i < dst->pd->nr_chips; i++) {
+		struct dsa_switch *ds = dst->ds[i];
+
+		if (ds != NULL)
+			ret = dsa_switch_suspend(ds);
+	}
+
+	return ret;
+}
+
+static int dsa_resume(struct device *d)
+{
+	struct platform_device *pdev = to_platform_device(d);
+	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
+	int i, ret = 0;
+
+	for (i = 0; i < dst->pd->nr_chips; i++) {
+		struct dsa_switch *ds = dst->ds[i];
+
+		if (ds != NULL)
+			ret = dsa_switch_resume(ds);
+	}
+
+	return ret;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
+
+static const struct of_device_id dsa_of_match_table[] = {
+	{ .compatible = "marvell,dsa", },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dsa_of_match_table);
+
+static struct platform_driver dsa_driver = {
+	.probe		= dsa_probe,
+	.remove		= dsa_remove,
+	.shutdown	= dsa_shutdown,
+	.driver = {
+		.name	= "dsa",
+		.of_match_table = dsa_of_match_table,
+		.pm	= &dsa_pm_ops,
+	},
+};
+
+int dsa_legacy_register(void)
+{
+	return platform_driver_register(&dsa_driver);
+}
+
+void dsa_legacy_unregister(void)
+{
+	platform_driver_unregister(&dsa_driver);
+}