xref: /linux/net/dsa/dsa.c (revision e5c86679d5e864947a52fb31e45a425dea3e7fa9)
1 /*
2  * net/dsa/dsa.c - Hardware switch handling
3  * Copyright (c) 2008-2009 Marvell Semiconductor
4  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/device.h>
13 #include <linux/list.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <net/dsa.h>
18 #include <linux/of.h>
19 #include <linux/of_mdio.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_net.h>
22 #include <linux/of_gpio.h>
23 #include <linux/sysfs.h>
24 #include <linux/phy_fixed.h>
25 #include <linux/gpio/consumer.h>
26 #include "dsa_priv.h"
27 
28 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
29 					    struct net_device *dev)
30 {
31 	/* Just return the original SKB */
32 	return skb;
33 }
34 
35 static const struct dsa_device_ops none_ops = {
36 	.xmit	= dsa_slave_notag_xmit,
37 	.rcv	= NULL,
38 };
39 
40 const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
41 #ifdef CONFIG_NET_DSA_TAG_DSA
42 	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
43 #endif
44 #ifdef CONFIG_NET_DSA_TAG_EDSA
45 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
46 #endif
47 #ifdef CONFIG_NET_DSA_TAG_TRAILER
48 	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
49 #endif
50 #ifdef CONFIG_NET_DSA_TAG_BRCM
51 	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
52 #endif
53 #ifdef CONFIG_NET_DSA_TAG_QCA
54 	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
55 #endif
56 	[DSA_TAG_PROTO_NONE] = &none_ops,
57 };
58 
59 /* switch driver registration ***********************************************/
60 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
61 static LIST_HEAD(dsa_switch_drivers);
62 
63 void register_switch_driver(struct dsa_switch_driver *drv)
64 {
65 	mutex_lock(&dsa_switch_drivers_mutex);
66 	list_add_tail(&drv->list, &dsa_switch_drivers);
67 	mutex_unlock(&dsa_switch_drivers_mutex);
68 }
69 EXPORT_SYMBOL_GPL(register_switch_driver);
70 
71 void unregister_switch_driver(struct dsa_switch_driver *drv)
72 {
73 	mutex_lock(&dsa_switch_drivers_mutex);
74 	list_del_init(&drv->list);
75 	mutex_unlock(&dsa_switch_drivers_mutex);
76 }
77 EXPORT_SYMBOL_GPL(unregister_switch_driver);
78 
79 static const struct dsa_switch_ops *
80 dsa_switch_probe(struct device *parent, struct device *host_dev, int sw_addr,
81 		 const char **_name, void **priv)
82 {
83 	const struct dsa_switch_ops *ret;
84 	struct list_head *list;
85 	const char *name;
86 
87 	ret = NULL;
88 	name = NULL;
89 
90 	mutex_lock(&dsa_switch_drivers_mutex);
91 	list_for_each(list, &dsa_switch_drivers) {
92 		const struct dsa_switch_ops *ops;
93 		struct dsa_switch_driver *drv;
94 
95 		drv = list_entry(list, struct dsa_switch_driver, list);
96 		ops = drv->ops;
97 
98 		name = ops->probe(parent, host_dev, sw_addr, priv);
99 		if (name != NULL) {
100 			ret = ops;
101 			break;
102 		}
103 	}
104 	mutex_unlock(&dsa_switch_drivers_mutex);
105 
106 	*_name = name;
107 
108 	return ret;
109 }
110 
111 /* basic switch operations **************************************************/
112 int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct device *dev,
113 		      struct dsa_port *dport, int port)
114 {
115 	struct device_node *port_dn = dport->dn;
116 	struct phy_device *phydev;
117 	int ret, mode;
118 
119 	if (of_phy_is_fixed_link(port_dn)) {
120 		ret = of_phy_register_fixed_link(port_dn);
121 		if (ret) {
122 			dev_err(dev, "failed to register fixed PHY\n");
123 			return ret;
124 		}
125 		phydev = of_phy_find_device(port_dn);
126 
127 		mode = of_get_phy_mode(port_dn);
128 		if (mode < 0)
129 			mode = PHY_INTERFACE_MODE_NA;
130 		phydev->interface = mode;
131 
132 		genphy_config_init(phydev);
133 		genphy_read_status(phydev);
134 		if (ds->ops->adjust_link)
135 			ds->ops->adjust_link(ds, port, phydev);
136 
137 		put_device(&phydev->mdio.dev);
138 	}
139 
140 	return 0;
141 }
142 
143 static int dsa_cpu_dsa_setups(struct dsa_switch *ds, struct device *dev)
144 {
145 	struct dsa_port *dport;
146 	int ret, port;
147 
148 	for (port = 0; port < ds->num_ports; port++) {
149 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
150 			continue;
151 
152 		dport = &ds->ports[port];
153 		ret = dsa_cpu_dsa_setup(ds, dev, dport, port);
154 		if (ret)
155 			return ret;
156 	}
157 	return 0;
158 }
159 
160 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
161 {
162 	const struct dsa_device_ops *ops;
163 
164 	if (tag_protocol >= DSA_TAG_LAST)
165 		return ERR_PTR(-EINVAL);
166 	ops = dsa_device_ops[tag_protocol];
167 
168 	if (!ops)
169 		return ERR_PTR(-ENOPROTOOPT);
170 
171 	return ops;
172 }
173 
174 int dsa_cpu_port_ethtool_setup(struct dsa_switch *ds)
175 {
176 	struct net_device *master;
177 	struct ethtool_ops *cpu_ops;
178 
179 	master = ds->dst->master_netdev;
180 	if (ds->master_netdev)
181 		master = ds->master_netdev;
182 
183 	cpu_ops = devm_kzalloc(ds->dev, sizeof(*cpu_ops), GFP_KERNEL);
184 	if (!cpu_ops)
185 		return -ENOMEM;
186 
187 	memcpy(&ds->dst->master_ethtool_ops, master->ethtool_ops,
188 	       sizeof(struct ethtool_ops));
189 	ds->dst->master_orig_ethtool_ops = master->ethtool_ops;
190 	memcpy(cpu_ops, &ds->dst->master_ethtool_ops,
191 	       sizeof(struct ethtool_ops));
192 	dsa_cpu_port_ethtool_init(cpu_ops);
193 	master->ethtool_ops = cpu_ops;
194 
195 	return 0;
196 }
197 
198 void dsa_cpu_port_ethtool_restore(struct dsa_switch *ds)
199 {
200 	struct net_device *master;
201 
202 	master = ds->dst->master_netdev;
203 	if (ds->master_netdev)
204 		master = ds->master_netdev;
205 
206 	master->ethtool_ops = ds->dst->master_orig_ethtool_ops;
207 }
208 
209 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
210 {
211 	const struct dsa_switch_ops *ops = ds->ops;
212 	struct dsa_switch_tree *dst = ds->dst;
213 	struct dsa_chip_data *cd = ds->cd;
214 	bool valid_name_found = false;
215 	int index = ds->index;
216 	int i, ret;
217 
218 	/*
219 	 * Validate supplied switch configuration.
220 	 */
221 	for (i = 0; i < ds->num_ports; i++) {
222 		char *name;
223 
224 		name = cd->port_names[i];
225 		if (name == NULL)
226 			continue;
227 
228 		if (!strcmp(name, "cpu")) {
229 			if (dst->cpu_switch) {
230 				netdev_err(dst->master_netdev,
231 					   "multiple cpu ports?!\n");
232 				return -EINVAL;
233 			}
234 			dst->cpu_switch = ds;
235 			dst->cpu_port = i;
236 			ds->cpu_port_mask |= 1 << i;
237 		} else if (!strcmp(name, "dsa")) {
238 			ds->dsa_port_mask |= 1 << i;
239 		} else {
240 			ds->enabled_port_mask |= 1 << i;
241 		}
242 		valid_name_found = true;
243 	}
244 
245 	if (!valid_name_found && i == ds->num_ports)
246 		return -EINVAL;
247 
248 	/* Make the built-in MII bus mask match the number of ports,
249 	 * switch drivers can override this later
250 	 */
251 	ds->phys_mii_mask = ds->enabled_port_mask;
252 
253 	/*
254 	 * If the CPU connects to this switch, set the switch tree
255 	 * tagging protocol to the preferred tagging format of this
256 	 * switch.
257 	 */
258 	if (dst->cpu_switch == ds) {
259 		enum dsa_tag_protocol tag_protocol;
260 
261 		tag_protocol = ops->get_tag_protocol(ds);
262 		dst->tag_ops = dsa_resolve_tag_protocol(tag_protocol);
263 		if (IS_ERR(dst->tag_ops))
264 			return PTR_ERR(dst->tag_ops);
265 
266 		dst->rcv = dst->tag_ops->rcv;
267 	}
268 
269 	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
270 
271 	/*
272 	 * Do basic register setup.
273 	 */
274 	ret = ops->setup(ds);
275 	if (ret < 0)
276 		return ret;
277 
278 	ret = dsa_switch_register_notifier(ds);
279 	if (ret)
280 		return ret;
281 
282 	if (ops->set_addr) {
283 		ret = ops->set_addr(ds, dst->master_netdev->dev_addr);
284 		if (ret < 0)
285 			return ret;
286 	}
287 
288 	if (!ds->slave_mii_bus && ops->phy_read) {
289 		ds->slave_mii_bus = devm_mdiobus_alloc(parent);
290 		if (!ds->slave_mii_bus)
291 			return -ENOMEM;
292 		dsa_slave_mii_bus_init(ds);
293 
294 		ret = mdiobus_register(ds->slave_mii_bus);
295 		if (ret < 0)
296 			return ret;
297 	}
298 
299 	/*
300 	 * Create network devices for physical switch ports.
301 	 */
302 	for (i = 0; i < ds->num_ports; i++) {
303 		ds->ports[i].dn = cd->port_dn[i];
304 
305 		if (!(ds->enabled_port_mask & (1 << i)))
306 			continue;
307 
308 		ret = dsa_slave_create(ds, parent, i, cd->port_names[i]);
309 		if (ret < 0)
310 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
311 				   index, i, cd->port_names[i], ret);
312 	}
313 
314 	/* Perform configuration of the CPU and DSA ports */
315 	ret = dsa_cpu_dsa_setups(ds, parent);
316 	if (ret < 0)
317 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
318 			   index);
319 
320 	ret = dsa_cpu_port_ethtool_setup(ds);
321 	if (ret)
322 		return ret;
323 
324 	return 0;
325 }
326 
327 static struct dsa_switch *
328 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
329 		 struct device *parent, struct device *host_dev)
330 {
331 	struct dsa_chip_data *cd = dst->pd->chip + index;
332 	const struct dsa_switch_ops *ops;
333 	struct dsa_switch *ds;
334 	int ret;
335 	const char *name;
336 	void *priv;
337 
338 	/*
339 	 * Probe for switch model.
340 	 */
341 	ops = dsa_switch_probe(parent, host_dev, cd->sw_addr, &name, &priv);
342 	if (!ops) {
343 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
344 			   index);
345 		return ERR_PTR(-EINVAL);
346 	}
347 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
348 		    index, name);
349 
350 
351 	/*
352 	 * Allocate and initialise switch state.
353 	 */
354 	ds = dsa_switch_alloc(parent, DSA_MAX_PORTS);
355 	if (!ds)
356 		return ERR_PTR(-ENOMEM);
357 
358 	ds->dst = dst;
359 	ds->index = index;
360 	ds->cd = cd;
361 	ds->ops = ops;
362 	ds->priv = priv;
363 
364 	ret = dsa_switch_setup_one(ds, parent);
365 	if (ret)
366 		return ERR_PTR(ret);
367 
368 	return ds;
369 }
370 
371 void dsa_cpu_dsa_destroy(struct dsa_port *port)
372 {
373 	struct device_node *port_dn = port->dn;
374 
375 	if (of_phy_is_fixed_link(port_dn))
376 		of_phy_deregister_fixed_link(port_dn);
377 }
378 
379 static void dsa_switch_destroy(struct dsa_switch *ds)
380 {
381 	int port;
382 
383 	/* Destroy network devices for physical switch ports. */
384 	for (port = 0; port < ds->num_ports; port++) {
385 		if (!(ds->enabled_port_mask & (1 << port)))
386 			continue;
387 
388 		if (!ds->ports[port].netdev)
389 			continue;
390 
391 		dsa_slave_destroy(ds->ports[port].netdev);
392 	}
393 
394 	/* Disable configuration of the CPU and DSA ports */
395 	for (port = 0; port < ds->num_ports; port++) {
396 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
397 			continue;
398 		dsa_cpu_dsa_destroy(&ds->ports[port]);
399 
400 		/* Clearing a bit which is not set does no harm */
401 		ds->cpu_port_mask |= ~(1 << port);
402 		ds->dsa_port_mask |= ~(1 << port);
403 	}
404 
405 	if (ds->slave_mii_bus && ds->ops->phy_read)
406 		mdiobus_unregister(ds->slave_mii_bus);
407 
408 	dsa_switch_unregister_notifier(ds);
409 }
410 
411 #ifdef CONFIG_PM_SLEEP
412 int dsa_switch_suspend(struct dsa_switch *ds)
413 {
414 	int i, ret = 0;
415 
416 	/* Suspend slave network devices */
417 	for (i = 0; i < ds->num_ports; i++) {
418 		if (!dsa_is_port_initialized(ds, i))
419 			continue;
420 
421 		ret = dsa_slave_suspend(ds->ports[i].netdev);
422 		if (ret)
423 			return ret;
424 	}
425 
426 	if (ds->ops->suspend)
427 		ret = ds->ops->suspend(ds);
428 
429 	return ret;
430 }
431 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
432 
433 int dsa_switch_resume(struct dsa_switch *ds)
434 {
435 	int i, ret = 0;
436 
437 	if (ds->ops->resume)
438 		ret = ds->ops->resume(ds);
439 
440 	if (ret)
441 		return ret;
442 
443 	/* Resume slave network devices */
444 	for (i = 0; i < ds->num_ports; i++) {
445 		if (!dsa_is_port_initialized(ds, i))
446 			continue;
447 
448 		ret = dsa_slave_resume(ds->ports[i].netdev);
449 		if (ret)
450 			return ret;
451 	}
452 
453 	return 0;
454 }
455 EXPORT_SYMBOL_GPL(dsa_switch_resume);
456 #endif
457 
458 /* platform driver init and cleanup *****************************************/
459 static int dev_is_class(struct device *dev, void *class)
460 {
461 	if (dev->class != NULL && !strcmp(dev->class->name, class))
462 		return 1;
463 
464 	return 0;
465 }
466 
467 static struct device *dev_find_class(struct device *parent, char *class)
468 {
469 	if (dev_is_class(parent, class)) {
470 		get_device(parent);
471 		return parent;
472 	}
473 
474 	return device_find_child(parent, class, dev_is_class);
475 }
476 
477 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
478 {
479 	struct device *d;
480 
481 	d = dev_find_class(dev, "mdio_bus");
482 	if (d != NULL) {
483 		struct mii_bus *bus;
484 
485 		bus = to_mii_bus(d);
486 		put_device(d);
487 
488 		return bus;
489 	}
490 
491 	return NULL;
492 }
493 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
494 
495 struct net_device *dsa_dev_to_net_device(struct device *dev)
496 {
497 	struct device *d;
498 
499 	d = dev_find_class(dev, "net");
500 	if (d != NULL) {
501 		struct net_device *nd;
502 
503 		nd = to_net_dev(d);
504 		dev_hold(nd);
505 		put_device(d);
506 
507 		return nd;
508 	}
509 
510 	return NULL;
511 }
512 EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
513 
514 #ifdef CONFIG_OF
515 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
516 					struct dsa_chip_data *cd,
517 					int chip_index, int port_index,
518 					struct device_node *link)
519 {
520 	const __be32 *reg;
521 	int link_sw_addr;
522 	struct device_node *parent_sw;
523 	int len;
524 
525 	parent_sw = of_get_parent(link);
526 	if (!parent_sw)
527 		return -EINVAL;
528 
529 	reg = of_get_property(parent_sw, "reg", &len);
530 	if (!reg || (len != sizeof(*reg) * 2))
531 		return -EINVAL;
532 
533 	/*
534 	 * Get the destination switch number from the second field of its 'reg'
535 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
536 	 */
537 	link_sw_addr = be32_to_cpup(reg + 1);
538 
539 	if (link_sw_addr >= pd->nr_chips)
540 		return -EINVAL;
541 
542 	cd->rtable[link_sw_addr] = port_index;
543 
544 	return 0;
545 }
546 
547 static int dsa_of_probe_links(struct dsa_platform_data *pd,
548 			      struct dsa_chip_data *cd,
549 			      int chip_index, int port_index,
550 			      struct device_node *port,
551 			      const char *port_name)
552 {
553 	struct device_node *link;
554 	int link_index;
555 	int ret;
556 
557 	for (link_index = 0;; link_index++) {
558 		link = of_parse_phandle(port, "link", link_index);
559 		if (!link)
560 			break;
561 
562 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
563 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
564 							 port_index, link);
565 			if (ret)
566 				return ret;
567 		}
568 	}
569 	return 0;
570 }
571 
572 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
573 {
574 	int i;
575 	int port_index;
576 
577 	for (i = 0; i < pd->nr_chips; i++) {
578 		port_index = 0;
579 		while (port_index < DSA_MAX_PORTS) {
580 			kfree(pd->chip[i].port_names[port_index]);
581 			port_index++;
582 		}
583 
584 		/* Drop our reference to the MDIO bus device */
585 		if (pd->chip[i].host_dev)
586 			put_device(pd->chip[i].host_dev);
587 	}
588 	kfree(pd->chip);
589 }
590 
591 static int dsa_of_probe(struct device *dev)
592 {
593 	struct device_node *np = dev->of_node;
594 	struct device_node *child, *mdio, *ethernet, *port;
595 	struct mii_bus *mdio_bus, *mdio_bus_switch;
596 	struct net_device *ethernet_dev;
597 	struct dsa_platform_data *pd;
598 	struct dsa_chip_data *cd;
599 	const char *port_name;
600 	int chip_index, port_index;
601 	const unsigned int *sw_addr, *port_reg;
602 	u32 eeprom_len;
603 	int ret;
604 
605 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
606 	if (!mdio)
607 		return -EINVAL;
608 
609 	mdio_bus = of_mdio_find_bus(mdio);
610 	if (!mdio_bus)
611 		return -EPROBE_DEFER;
612 
613 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
614 	if (!ethernet) {
615 		ret = -EINVAL;
616 		goto out_put_mdio;
617 	}
618 
619 	ethernet_dev = of_find_net_device_by_node(ethernet);
620 	if (!ethernet_dev) {
621 		ret = -EPROBE_DEFER;
622 		goto out_put_mdio;
623 	}
624 
625 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
626 	if (!pd) {
627 		ret = -ENOMEM;
628 		goto out_put_ethernet;
629 	}
630 
631 	dev->platform_data = pd;
632 	pd->of_netdev = ethernet_dev;
633 	pd->nr_chips = of_get_available_child_count(np);
634 	if (pd->nr_chips > DSA_MAX_SWITCHES)
635 		pd->nr_chips = DSA_MAX_SWITCHES;
636 
637 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
638 			   GFP_KERNEL);
639 	if (!pd->chip) {
640 		ret = -ENOMEM;
641 		goto out_free;
642 	}
643 
644 	chip_index = -1;
645 	for_each_available_child_of_node(np, child) {
646 		int i;
647 
648 		chip_index++;
649 		cd = &pd->chip[chip_index];
650 
651 		cd->of_node = child;
652 
653 		/* Initialize the routing table */
654 		for (i = 0; i < DSA_MAX_SWITCHES; ++i)
655 			cd->rtable[i] = DSA_RTABLE_NONE;
656 
657 		/* When assigning the host device, increment its refcount */
658 		cd->host_dev = get_device(&mdio_bus->dev);
659 
660 		sw_addr = of_get_property(child, "reg", NULL);
661 		if (!sw_addr)
662 			continue;
663 
664 		cd->sw_addr = be32_to_cpup(sw_addr);
665 		if (cd->sw_addr >= PHY_MAX_ADDR)
666 			continue;
667 
668 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
669 			cd->eeprom_len = eeprom_len;
670 
671 		mdio = of_parse_phandle(child, "mii-bus", 0);
672 		if (mdio) {
673 			mdio_bus_switch = of_mdio_find_bus(mdio);
674 			if (!mdio_bus_switch) {
675 				ret = -EPROBE_DEFER;
676 				goto out_free_chip;
677 			}
678 
679 			/* Drop the mdio_bus device ref, replacing the host
680 			 * device with the mdio_bus_switch device, keeping
681 			 * the refcount from of_mdio_find_bus() above.
682 			 */
683 			put_device(cd->host_dev);
684 			cd->host_dev = &mdio_bus_switch->dev;
685 		}
686 
687 		for_each_available_child_of_node(child, port) {
688 			port_reg = of_get_property(port, "reg", NULL);
689 			if (!port_reg)
690 				continue;
691 
692 			port_index = be32_to_cpup(port_reg);
693 			if (port_index >= DSA_MAX_PORTS)
694 				break;
695 
696 			port_name = of_get_property(port, "label", NULL);
697 			if (!port_name)
698 				continue;
699 
700 			cd->port_dn[port_index] = port;
701 
702 			cd->port_names[port_index] = kstrdup(port_name,
703 					GFP_KERNEL);
704 			if (!cd->port_names[port_index]) {
705 				ret = -ENOMEM;
706 				goto out_free_chip;
707 			}
708 
709 			ret = dsa_of_probe_links(pd, cd, chip_index,
710 						 port_index, port, port_name);
711 			if (ret)
712 				goto out_free_chip;
713 
714 		}
715 	}
716 
717 	/* The individual chips hold their own refcount on the mdio bus,
718 	 * so drop ours */
719 	put_device(&mdio_bus->dev);
720 
721 	return 0;
722 
723 out_free_chip:
724 	dsa_of_free_platform_data(pd);
725 out_free:
726 	kfree(pd);
727 	dev->platform_data = NULL;
728 out_put_ethernet:
729 	put_device(&ethernet_dev->dev);
730 out_put_mdio:
731 	put_device(&mdio_bus->dev);
732 	return ret;
733 }
734 
735 static void dsa_of_remove(struct device *dev)
736 {
737 	struct dsa_platform_data *pd = dev->platform_data;
738 
739 	if (!dev->of_node)
740 		return;
741 
742 	dsa_of_free_platform_data(pd);
743 	put_device(&pd->of_netdev->dev);
744 	kfree(pd);
745 }
746 #else
747 static inline int dsa_of_probe(struct device *dev)
748 {
749 	return 0;
750 }
751 
752 static inline void dsa_of_remove(struct device *dev)
753 {
754 }
755 #endif
756 
757 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
758 			 struct device *parent, struct dsa_platform_data *pd)
759 {
760 	int i;
761 	unsigned configured = 0;
762 
763 	dst->pd = pd;
764 	dst->master_netdev = dev;
765 	dst->cpu_port = -1;
766 
767 	for (i = 0; i < pd->nr_chips; i++) {
768 		struct dsa_switch *ds;
769 
770 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
771 		if (IS_ERR(ds)) {
772 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
773 				   i, PTR_ERR(ds));
774 			continue;
775 		}
776 
777 		dst->ds[i] = ds;
778 
779 		++configured;
780 	}
781 
782 	/*
783 	 * If no switch was found, exit cleanly
784 	 */
785 	if (!configured)
786 		return -EPROBE_DEFER;
787 
788 	/*
789 	 * If we use a tagging format that doesn't have an ethertype
790 	 * field, make sure that all packets from this point on get
791 	 * sent to the tag format's receive function.
792 	 */
793 	wmb();
794 	dev->dsa_ptr = (void *)dst;
795 
796 	return 0;
797 }
798 
799 static int dsa_probe(struct platform_device *pdev)
800 {
801 	struct dsa_platform_data *pd = pdev->dev.platform_data;
802 	struct net_device *dev;
803 	struct dsa_switch_tree *dst;
804 	int ret;
805 
806 	if (pdev->dev.of_node) {
807 		ret = dsa_of_probe(&pdev->dev);
808 		if (ret)
809 			return ret;
810 
811 		pd = pdev->dev.platform_data;
812 	}
813 
814 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
815 		return -EINVAL;
816 
817 	if (pd->of_netdev) {
818 		dev = pd->of_netdev;
819 		dev_hold(dev);
820 	} else {
821 		dev = dsa_dev_to_net_device(pd->netdev);
822 	}
823 	if (dev == NULL) {
824 		ret = -EPROBE_DEFER;
825 		goto out;
826 	}
827 
828 	if (dev->dsa_ptr != NULL) {
829 		dev_put(dev);
830 		ret = -EEXIST;
831 		goto out;
832 	}
833 
834 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
835 	if (dst == NULL) {
836 		dev_put(dev);
837 		ret = -ENOMEM;
838 		goto out;
839 	}
840 
841 	platform_set_drvdata(pdev, dst);
842 
843 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
844 	if (ret) {
845 		dev_put(dev);
846 		goto out;
847 	}
848 
849 	return 0;
850 
851 out:
852 	dsa_of_remove(&pdev->dev);
853 
854 	return ret;
855 }
856 
857 static void dsa_remove_dst(struct dsa_switch_tree *dst)
858 {
859 	int i;
860 
861 	dst->master_netdev->dsa_ptr = NULL;
862 
863 	/* If we used a tagging format that doesn't have an ethertype
864 	 * field, make sure that all packets from this point get sent
865 	 * without the tag and go through the regular receive path.
866 	 */
867 	wmb();
868 
869 	for (i = 0; i < dst->pd->nr_chips; i++) {
870 		struct dsa_switch *ds = dst->ds[i];
871 
872 		if (ds)
873 			dsa_switch_destroy(ds);
874 	}
875 
876 	dsa_cpu_port_ethtool_restore(dst->cpu_switch);
877 
878 	dev_put(dst->master_netdev);
879 }
880 
881 static int dsa_remove(struct platform_device *pdev)
882 {
883 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
884 
885 	dsa_remove_dst(dst);
886 	dsa_of_remove(&pdev->dev);
887 
888 	return 0;
889 }
890 
891 static void dsa_shutdown(struct platform_device *pdev)
892 {
893 }
894 
895 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
896 			  struct packet_type *pt, struct net_device *orig_dev)
897 {
898 	struct dsa_switch_tree *dst = dev->dsa_ptr;
899 
900 	if (unlikely(dst == NULL)) {
901 		kfree_skb(skb);
902 		return 0;
903 	}
904 
905 	return dst->rcv(skb, dev, pt, orig_dev);
906 }
907 
908 static struct packet_type dsa_pack_type __read_mostly = {
909 	.type	= cpu_to_be16(ETH_P_XDSA),
910 	.func	= dsa_switch_rcv,
911 };
912 
913 #ifdef CONFIG_PM_SLEEP
914 static int dsa_suspend(struct device *d)
915 {
916 	struct platform_device *pdev = to_platform_device(d);
917 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
918 	int i, ret = 0;
919 
920 	for (i = 0; i < dst->pd->nr_chips; i++) {
921 		struct dsa_switch *ds = dst->ds[i];
922 
923 		if (ds != NULL)
924 			ret = dsa_switch_suspend(ds);
925 	}
926 
927 	return ret;
928 }
929 
930 static int dsa_resume(struct device *d)
931 {
932 	struct platform_device *pdev = to_platform_device(d);
933 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
934 	int i, ret = 0;
935 
936 	for (i = 0; i < dst->pd->nr_chips; i++) {
937 		struct dsa_switch *ds = dst->ds[i];
938 
939 		if (ds != NULL)
940 			ret = dsa_switch_resume(ds);
941 	}
942 
943 	return ret;
944 }
945 #endif
946 
947 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
948 
949 static const struct of_device_id dsa_of_match_table[] = {
950 	{ .compatible = "marvell,dsa", },
951 	{}
952 };
953 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
954 
955 static struct platform_driver dsa_driver = {
956 	.probe		= dsa_probe,
957 	.remove		= dsa_remove,
958 	.shutdown	= dsa_shutdown,
959 	.driver = {
960 		.name	= "dsa",
961 		.of_match_table = dsa_of_match_table,
962 		.pm	= &dsa_pm_ops,
963 	},
964 };
965 
966 static int __init dsa_init_module(void)
967 {
968 	int rc;
969 
970 	rc = dsa_slave_register_notifier();
971 	if (rc)
972 		return rc;
973 
974 	rc = platform_driver_register(&dsa_driver);
975 	if (rc)
976 		return rc;
977 
978 	dev_add_pack(&dsa_pack_type);
979 
980 	return 0;
981 }
982 module_init(dsa_init_module);
983 
984 static void __exit dsa_cleanup_module(void)
985 {
986 	dsa_slave_unregister_notifier();
987 	dev_remove_pack(&dsa_pack_type);
988 	platform_driver_unregister(&dsa_driver);
989 }
990 module_exit(dsa_cleanup_module);
991 
992 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
993 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
994 MODULE_LICENSE("GPL");
995 MODULE_ALIAS("platform:dsa");
996