xref: /openbmc/linux/net/dsa/dsa.c (revision 4f139972b489f8bc2c821aa25ac65018d92af3f7)
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 <linux/of.h>
18 #include <linux/of_mdio.h>
19 #include <linux/of_platform.h>
20 #include <linux/of_net.h>
21 #include <linux/of_gpio.h>
22 #include <linux/netdevice.h>
23 #include <linux/sysfs.h>
24 #include <linux/phy_fixed.h>
25 #include <linux/gpio/consumer.h>
26 #include <net/dsa.h>
27 #include "dsa_priv.h"
28 
29 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
30 					    struct net_device *dev)
31 {
32 	/* Just return the original SKB */
33 	return skb;
34 }
35 
36 static const struct dsa_device_ops none_ops = {
37 	.xmit	= dsa_slave_notag_xmit,
38 	.rcv	= NULL,
39 };
40 
41 const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
42 #ifdef CONFIG_NET_DSA_TAG_DSA
43 	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
44 #endif
45 #ifdef CONFIG_NET_DSA_TAG_EDSA
46 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
47 #endif
48 #ifdef CONFIG_NET_DSA_TAG_TRAILER
49 	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
50 #endif
51 #ifdef CONFIG_NET_DSA_TAG_BRCM
52 	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
53 #endif
54 #ifdef CONFIG_NET_DSA_TAG_QCA
55 	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
56 #endif
57 	[DSA_TAG_PROTO_NONE] = &none_ops,
58 };
59 
60 /* switch driver registration ***********************************************/
61 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
62 static LIST_HEAD(dsa_switch_drivers);
63 
64 void register_switch_driver(struct dsa_switch_driver *drv)
65 {
66 	mutex_lock(&dsa_switch_drivers_mutex);
67 	list_add_tail(&drv->list, &dsa_switch_drivers);
68 	mutex_unlock(&dsa_switch_drivers_mutex);
69 }
70 EXPORT_SYMBOL_GPL(register_switch_driver);
71 
72 void unregister_switch_driver(struct dsa_switch_driver *drv)
73 {
74 	mutex_lock(&dsa_switch_drivers_mutex);
75 	list_del_init(&drv->list);
76 	mutex_unlock(&dsa_switch_drivers_mutex);
77 }
78 EXPORT_SYMBOL_GPL(unregister_switch_driver);
79 
80 static const struct dsa_switch_ops *
81 dsa_switch_probe(struct device *parent, struct device *host_dev, int sw_addr,
82 		 const char **_name, void **priv)
83 {
84 	const struct dsa_switch_ops *ret;
85 	struct list_head *list;
86 	const char *name;
87 
88 	ret = NULL;
89 	name = NULL;
90 
91 	mutex_lock(&dsa_switch_drivers_mutex);
92 	list_for_each(list, &dsa_switch_drivers) {
93 		const struct dsa_switch_ops *ops;
94 		struct dsa_switch_driver *drv;
95 
96 		drv = list_entry(list, struct dsa_switch_driver, list);
97 		ops = drv->ops;
98 
99 		name = ops->probe(parent, host_dev, sw_addr, priv);
100 		if (name != NULL) {
101 			ret = ops;
102 			break;
103 		}
104 	}
105 	mutex_unlock(&dsa_switch_drivers_mutex);
106 
107 	*_name = name;
108 
109 	return ret;
110 }
111 
112 /* basic switch operations **************************************************/
113 int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct device *dev,
114 		      struct dsa_port *dport, int port)
115 {
116 	struct device_node *port_dn = dport->dn;
117 	struct phy_device *phydev;
118 	int ret, mode;
119 
120 	if (of_phy_is_fixed_link(port_dn)) {
121 		ret = of_phy_register_fixed_link(port_dn);
122 		if (ret) {
123 			dev_err(dev, "failed to register fixed PHY\n");
124 			return ret;
125 		}
126 		phydev = of_phy_find_device(port_dn);
127 
128 		mode = of_get_phy_mode(port_dn);
129 		if (mode < 0)
130 			mode = PHY_INTERFACE_MODE_NA;
131 		phydev->interface = mode;
132 
133 		genphy_config_init(phydev);
134 		genphy_read_status(phydev);
135 		if (ds->ops->adjust_link)
136 			ds->ops->adjust_link(ds, port, phydev);
137 
138 		put_device(&phydev->mdio.dev);
139 	}
140 
141 	return 0;
142 }
143 
144 static int dsa_cpu_dsa_setups(struct dsa_switch *ds, struct device *dev)
145 {
146 	struct dsa_port *dport;
147 	int ret, port;
148 
149 	for (port = 0; port < ds->num_ports; port++) {
150 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
151 			continue;
152 
153 		dport = &ds->ports[port];
154 		ret = dsa_cpu_dsa_setup(ds, dev, dport, port);
155 		if (ret)
156 			return ret;
157 	}
158 	return 0;
159 }
160 
161 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
162 {
163 	const struct dsa_device_ops *ops;
164 
165 	if (tag_protocol >= DSA_TAG_LAST)
166 		return ERR_PTR(-EINVAL);
167 	ops = dsa_device_ops[tag_protocol];
168 
169 	if (!ops)
170 		return ERR_PTR(-ENOPROTOOPT);
171 
172 	return ops;
173 }
174 
175 int dsa_cpu_port_ethtool_setup(struct dsa_switch *ds)
176 {
177 	struct net_device *master;
178 	struct ethtool_ops *cpu_ops;
179 
180 	master = ds->dst->master_netdev;
181 	if (ds->master_netdev)
182 		master = ds->master_netdev;
183 
184 	cpu_ops = devm_kzalloc(ds->dev, sizeof(*cpu_ops), GFP_KERNEL);
185 	if (!cpu_ops)
186 		return -ENOMEM;
187 
188 	memcpy(&ds->dst->master_ethtool_ops, master->ethtool_ops,
189 	       sizeof(struct ethtool_ops));
190 	ds->dst->master_orig_ethtool_ops = master->ethtool_ops;
191 	memcpy(cpu_ops, &ds->dst->master_ethtool_ops,
192 	       sizeof(struct ethtool_ops));
193 	dsa_cpu_port_ethtool_init(cpu_ops);
194 	master->ethtool_ops = cpu_ops;
195 
196 	return 0;
197 }
198 
199 void dsa_cpu_port_ethtool_restore(struct dsa_switch *ds)
200 {
201 	struct net_device *master;
202 
203 	master = ds->dst->master_netdev;
204 	if (ds->master_netdev)
205 		master = ds->master_netdev;
206 
207 	master->ethtool_ops = ds->dst->master_orig_ethtool_ops;
208 }
209 
210 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
211 {
212 	const struct dsa_switch_ops *ops = ds->ops;
213 	struct dsa_switch_tree *dst = ds->dst;
214 	struct dsa_chip_data *cd = ds->cd;
215 	bool valid_name_found = false;
216 	int index = ds->index;
217 	int i, ret;
218 
219 	/*
220 	 * Validate supplied switch configuration.
221 	 */
222 	for (i = 0; i < ds->num_ports; i++) {
223 		char *name;
224 
225 		name = cd->port_names[i];
226 		if (name == NULL)
227 			continue;
228 
229 		if (!strcmp(name, "cpu")) {
230 			if (dst->cpu_switch) {
231 				netdev_err(dst->master_netdev,
232 					   "multiple cpu ports?!\n");
233 				return -EINVAL;
234 			}
235 			dst->cpu_switch = ds;
236 			dst->cpu_port = i;
237 			ds->cpu_port_mask |= 1 << i;
238 		} else if (!strcmp(name, "dsa")) {
239 			ds->dsa_port_mask |= 1 << i;
240 		} else {
241 			ds->enabled_port_mask |= 1 << i;
242 		}
243 		valid_name_found = true;
244 	}
245 
246 	if (!valid_name_found && i == ds->num_ports)
247 		return -EINVAL;
248 
249 	/* Make the built-in MII bus mask match the number of ports,
250 	 * switch drivers can override this later
251 	 */
252 	ds->phys_mii_mask = ds->enabled_port_mask;
253 
254 	/*
255 	 * If the CPU connects to this switch, set the switch tree
256 	 * tagging protocol to the preferred tagging format of this
257 	 * switch.
258 	 */
259 	if (dst->cpu_switch == ds) {
260 		enum dsa_tag_protocol tag_protocol;
261 
262 		tag_protocol = ops->get_tag_protocol(ds);
263 		dst->tag_ops = dsa_resolve_tag_protocol(tag_protocol);
264 		if (IS_ERR(dst->tag_ops))
265 			return PTR_ERR(dst->tag_ops);
266 
267 		dst->rcv = dst->tag_ops->rcv;
268 	}
269 
270 	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
271 
272 	/*
273 	 * Do basic register setup.
274 	 */
275 	ret = ops->setup(ds);
276 	if (ret < 0)
277 		return ret;
278 
279 	ret = dsa_switch_register_notifier(ds);
280 	if (ret)
281 		return ret;
282 
283 	if (ops->set_addr) {
284 		ret = ops->set_addr(ds, dst->master_netdev->dev_addr);
285 		if (ret < 0)
286 			return ret;
287 	}
288 
289 	if (!ds->slave_mii_bus && ops->phy_read) {
290 		ds->slave_mii_bus = devm_mdiobus_alloc(parent);
291 		if (!ds->slave_mii_bus)
292 			return -ENOMEM;
293 		dsa_slave_mii_bus_init(ds);
294 
295 		ret = mdiobus_register(ds->slave_mii_bus);
296 		if (ret < 0)
297 			return ret;
298 	}
299 
300 	/*
301 	 * Create network devices for physical switch ports.
302 	 */
303 	for (i = 0; i < ds->num_ports; i++) {
304 		ds->ports[i].dn = cd->port_dn[i];
305 
306 		if (!(ds->enabled_port_mask & (1 << i)))
307 			continue;
308 
309 		ret = dsa_slave_create(ds, parent, i, cd->port_names[i]);
310 		if (ret < 0)
311 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
312 				   index, i, cd->port_names[i], ret);
313 	}
314 
315 	/* Perform configuration of the CPU and DSA ports */
316 	ret = dsa_cpu_dsa_setups(ds, parent);
317 	if (ret < 0)
318 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
319 			   index);
320 
321 	ret = dsa_cpu_port_ethtool_setup(ds);
322 	if (ret)
323 		return ret;
324 
325 	return 0;
326 }
327 
328 static struct dsa_switch *
329 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
330 		 struct device *parent, struct device *host_dev)
331 {
332 	struct dsa_chip_data *cd = dst->pd->chip + index;
333 	const struct dsa_switch_ops *ops;
334 	struct dsa_switch *ds;
335 	int ret;
336 	const char *name;
337 	void *priv;
338 
339 	/*
340 	 * Probe for switch model.
341 	 */
342 	ops = dsa_switch_probe(parent, host_dev, cd->sw_addr, &name, &priv);
343 	if (!ops) {
344 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
345 			   index);
346 		return ERR_PTR(-EINVAL);
347 	}
348 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
349 		    index, name);
350 
351 
352 	/*
353 	 * Allocate and initialise switch state.
354 	 */
355 	ds = dsa_switch_alloc(parent, DSA_MAX_PORTS);
356 	if (!ds)
357 		return ERR_PTR(-ENOMEM);
358 
359 	ds->dst = dst;
360 	ds->index = index;
361 	ds->cd = cd;
362 	ds->ops = ops;
363 	ds->priv = priv;
364 
365 	ret = dsa_switch_setup_one(ds, parent);
366 	if (ret)
367 		return ERR_PTR(ret);
368 
369 	return ds;
370 }
371 
372 void dsa_cpu_dsa_destroy(struct dsa_port *port)
373 {
374 	struct device_node *port_dn = port->dn;
375 
376 	if (of_phy_is_fixed_link(port_dn))
377 		of_phy_deregister_fixed_link(port_dn);
378 }
379 
380 static void dsa_switch_destroy(struct dsa_switch *ds)
381 {
382 	int port;
383 
384 	/* Destroy network devices for physical switch ports. */
385 	for (port = 0; port < ds->num_ports; port++) {
386 		if (!(ds->enabled_port_mask & (1 << port)))
387 			continue;
388 
389 		if (!ds->ports[port].netdev)
390 			continue;
391 
392 		dsa_slave_destroy(ds->ports[port].netdev);
393 	}
394 
395 	/* Disable configuration of the CPU and DSA ports */
396 	for (port = 0; port < ds->num_ports; port++) {
397 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
398 			continue;
399 		dsa_cpu_dsa_destroy(&ds->ports[port]);
400 
401 		/* Clearing a bit which is not set does no harm */
402 		ds->cpu_port_mask |= ~(1 << port);
403 		ds->dsa_port_mask |= ~(1 << port);
404 	}
405 
406 	if (ds->slave_mii_bus && ds->ops->phy_read)
407 		mdiobus_unregister(ds->slave_mii_bus);
408 
409 	dsa_switch_unregister_notifier(ds);
410 }
411 
412 #ifdef CONFIG_PM_SLEEP
413 int dsa_switch_suspend(struct dsa_switch *ds)
414 {
415 	int i, ret = 0;
416 
417 	/* Suspend slave network devices */
418 	for (i = 0; i < ds->num_ports; i++) {
419 		if (!dsa_is_port_initialized(ds, i))
420 			continue;
421 
422 		ret = dsa_slave_suspend(ds->ports[i].netdev);
423 		if (ret)
424 			return ret;
425 	}
426 
427 	if (ds->ops->suspend)
428 		ret = ds->ops->suspend(ds);
429 
430 	return ret;
431 }
432 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
433 
434 int dsa_switch_resume(struct dsa_switch *ds)
435 {
436 	int i, ret = 0;
437 
438 	if (ds->ops->resume)
439 		ret = ds->ops->resume(ds);
440 
441 	if (ret)
442 		return ret;
443 
444 	/* Resume slave network devices */
445 	for (i = 0; i < ds->num_ports; i++) {
446 		if (!dsa_is_port_initialized(ds, i))
447 			continue;
448 
449 		ret = dsa_slave_resume(ds->ports[i].netdev);
450 		if (ret)
451 			return ret;
452 	}
453 
454 	return 0;
455 }
456 EXPORT_SYMBOL_GPL(dsa_switch_resume);
457 #endif
458 
459 /* platform driver init and cleanup *****************************************/
460 static int dev_is_class(struct device *dev, void *class)
461 {
462 	if (dev->class != NULL && !strcmp(dev->class->name, class))
463 		return 1;
464 
465 	return 0;
466 }
467 
468 static struct device *dev_find_class(struct device *parent, char *class)
469 {
470 	if (dev_is_class(parent, class)) {
471 		get_device(parent);
472 		return parent;
473 	}
474 
475 	return device_find_child(parent, class, dev_is_class);
476 }
477 
478 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
479 {
480 	struct device *d;
481 
482 	d = dev_find_class(dev, "mdio_bus");
483 	if (d != NULL) {
484 		struct mii_bus *bus;
485 
486 		bus = to_mii_bus(d);
487 		put_device(d);
488 
489 		return bus;
490 	}
491 
492 	return NULL;
493 }
494 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
495 
496 struct net_device *dsa_dev_to_net_device(struct device *dev)
497 {
498 	struct device *d;
499 
500 	d = dev_find_class(dev, "net");
501 	if (d != NULL) {
502 		struct net_device *nd;
503 
504 		nd = to_net_dev(d);
505 		dev_hold(nd);
506 		put_device(d);
507 
508 		return nd;
509 	}
510 
511 	return NULL;
512 }
513 EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
514 
515 #ifdef CONFIG_OF
516 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
517 					struct dsa_chip_data *cd,
518 					int chip_index, int port_index,
519 					struct device_node *link)
520 {
521 	const __be32 *reg;
522 	int link_sw_addr;
523 	struct device_node *parent_sw;
524 	int len;
525 
526 	parent_sw = of_get_parent(link);
527 	if (!parent_sw)
528 		return -EINVAL;
529 
530 	reg = of_get_property(parent_sw, "reg", &len);
531 	if (!reg || (len != sizeof(*reg) * 2))
532 		return -EINVAL;
533 
534 	/*
535 	 * Get the destination switch number from the second field of its 'reg'
536 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
537 	 */
538 	link_sw_addr = be32_to_cpup(reg + 1);
539 
540 	if (link_sw_addr >= pd->nr_chips)
541 		return -EINVAL;
542 
543 	cd->rtable[link_sw_addr] = port_index;
544 
545 	return 0;
546 }
547 
548 static int dsa_of_probe_links(struct dsa_platform_data *pd,
549 			      struct dsa_chip_data *cd,
550 			      int chip_index, int port_index,
551 			      struct device_node *port,
552 			      const char *port_name)
553 {
554 	struct device_node *link;
555 	int link_index;
556 	int ret;
557 
558 	for (link_index = 0;; link_index++) {
559 		link = of_parse_phandle(port, "link", link_index);
560 		if (!link)
561 			break;
562 
563 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
564 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
565 							 port_index, link);
566 			if (ret)
567 				return ret;
568 		}
569 	}
570 	return 0;
571 }
572 
573 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
574 {
575 	int i;
576 	int port_index;
577 
578 	for (i = 0; i < pd->nr_chips; i++) {
579 		port_index = 0;
580 		while (port_index < DSA_MAX_PORTS) {
581 			kfree(pd->chip[i].port_names[port_index]);
582 			port_index++;
583 		}
584 
585 		/* Drop our reference to the MDIO bus device */
586 		if (pd->chip[i].host_dev)
587 			put_device(pd->chip[i].host_dev);
588 	}
589 	kfree(pd->chip);
590 }
591 
592 static int dsa_of_probe(struct device *dev)
593 {
594 	struct device_node *np = dev->of_node;
595 	struct device_node *child, *mdio, *ethernet, *port;
596 	struct mii_bus *mdio_bus, *mdio_bus_switch;
597 	struct net_device *ethernet_dev;
598 	struct dsa_platform_data *pd;
599 	struct dsa_chip_data *cd;
600 	const char *port_name;
601 	int chip_index, port_index;
602 	const unsigned int *sw_addr, *port_reg;
603 	u32 eeprom_len;
604 	int ret;
605 
606 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
607 	if (!mdio)
608 		return -EINVAL;
609 
610 	mdio_bus = of_mdio_find_bus(mdio);
611 	if (!mdio_bus)
612 		return -EPROBE_DEFER;
613 
614 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
615 	if (!ethernet) {
616 		ret = -EINVAL;
617 		goto out_put_mdio;
618 	}
619 
620 	ethernet_dev = of_find_net_device_by_node(ethernet);
621 	if (!ethernet_dev) {
622 		ret = -EPROBE_DEFER;
623 		goto out_put_mdio;
624 	}
625 
626 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
627 	if (!pd) {
628 		ret = -ENOMEM;
629 		goto out_put_ethernet;
630 	}
631 
632 	dev->platform_data = pd;
633 	pd->of_netdev = ethernet_dev;
634 	pd->nr_chips = of_get_available_child_count(np);
635 	if (pd->nr_chips > DSA_MAX_SWITCHES)
636 		pd->nr_chips = DSA_MAX_SWITCHES;
637 
638 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
639 			   GFP_KERNEL);
640 	if (!pd->chip) {
641 		ret = -ENOMEM;
642 		goto out_free;
643 	}
644 
645 	chip_index = -1;
646 	for_each_available_child_of_node(np, child) {
647 		int i;
648 
649 		chip_index++;
650 		cd = &pd->chip[chip_index];
651 
652 		cd->of_node = child;
653 
654 		/* Initialize the routing table */
655 		for (i = 0; i < DSA_MAX_SWITCHES; ++i)
656 			cd->rtable[i] = DSA_RTABLE_NONE;
657 
658 		/* When assigning the host device, increment its refcount */
659 		cd->host_dev = get_device(&mdio_bus->dev);
660 
661 		sw_addr = of_get_property(child, "reg", NULL);
662 		if (!sw_addr)
663 			continue;
664 
665 		cd->sw_addr = be32_to_cpup(sw_addr);
666 		if (cd->sw_addr >= PHY_MAX_ADDR)
667 			continue;
668 
669 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
670 			cd->eeprom_len = eeprom_len;
671 
672 		mdio = of_parse_phandle(child, "mii-bus", 0);
673 		if (mdio) {
674 			mdio_bus_switch = of_mdio_find_bus(mdio);
675 			if (!mdio_bus_switch) {
676 				ret = -EPROBE_DEFER;
677 				goto out_free_chip;
678 			}
679 
680 			/* Drop the mdio_bus device ref, replacing the host
681 			 * device with the mdio_bus_switch device, keeping
682 			 * the refcount from of_mdio_find_bus() above.
683 			 */
684 			put_device(cd->host_dev);
685 			cd->host_dev = &mdio_bus_switch->dev;
686 		}
687 
688 		for_each_available_child_of_node(child, port) {
689 			port_reg = of_get_property(port, "reg", NULL);
690 			if (!port_reg)
691 				continue;
692 
693 			port_index = be32_to_cpup(port_reg);
694 			if (port_index >= DSA_MAX_PORTS)
695 				break;
696 
697 			port_name = of_get_property(port, "label", NULL);
698 			if (!port_name)
699 				continue;
700 
701 			cd->port_dn[port_index] = port;
702 
703 			cd->port_names[port_index] = kstrdup(port_name,
704 					GFP_KERNEL);
705 			if (!cd->port_names[port_index]) {
706 				ret = -ENOMEM;
707 				goto out_free_chip;
708 			}
709 
710 			ret = dsa_of_probe_links(pd, cd, chip_index,
711 						 port_index, port, port_name);
712 			if (ret)
713 				goto out_free_chip;
714 
715 		}
716 	}
717 
718 	/* The individual chips hold their own refcount on the mdio bus,
719 	 * so drop ours */
720 	put_device(&mdio_bus->dev);
721 
722 	return 0;
723 
724 out_free_chip:
725 	dsa_of_free_platform_data(pd);
726 out_free:
727 	kfree(pd);
728 	dev->platform_data = NULL;
729 out_put_ethernet:
730 	put_device(&ethernet_dev->dev);
731 out_put_mdio:
732 	put_device(&mdio_bus->dev);
733 	return ret;
734 }
735 
736 static void dsa_of_remove(struct device *dev)
737 {
738 	struct dsa_platform_data *pd = dev->platform_data;
739 
740 	if (!dev->of_node)
741 		return;
742 
743 	dsa_of_free_platform_data(pd);
744 	put_device(&pd->of_netdev->dev);
745 	kfree(pd);
746 }
747 #else
748 static inline int dsa_of_probe(struct device *dev)
749 {
750 	return 0;
751 }
752 
753 static inline void dsa_of_remove(struct device *dev)
754 {
755 }
756 #endif
757 
758 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
759 			 struct device *parent, struct dsa_platform_data *pd)
760 {
761 	int i;
762 	unsigned configured = 0;
763 
764 	dst->pd = pd;
765 	dst->master_netdev = dev;
766 	dst->cpu_port = -1;
767 
768 	for (i = 0; i < pd->nr_chips; i++) {
769 		struct dsa_switch *ds;
770 
771 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
772 		if (IS_ERR(ds)) {
773 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
774 				   i, PTR_ERR(ds));
775 			continue;
776 		}
777 
778 		dst->ds[i] = ds;
779 
780 		++configured;
781 	}
782 
783 	/*
784 	 * If no switch was found, exit cleanly
785 	 */
786 	if (!configured)
787 		return -EPROBE_DEFER;
788 
789 	/*
790 	 * If we use a tagging format that doesn't have an ethertype
791 	 * field, make sure that all packets from this point on get
792 	 * sent to the tag format's receive function.
793 	 */
794 	wmb();
795 	dev->dsa_ptr = (void *)dst;
796 
797 	return 0;
798 }
799 
800 static int dsa_probe(struct platform_device *pdev)
801 {
802 	struct dsa_platform_data *pd = pdev->dev.platform_data;
803 	struct net_device *dev;
804 	struct dsa_switch_tree *dst;
805 	int ret;
806 
807 	if (pdev->dev.of_node) {
808 		ret = dsa_of_probe(&pdev->dev);
809 		if (ret)
810 			return ret;
811 
812 		pd = pdev->dev.platform_data;
813 	}
814 
815 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
816 		return -EINVAL;
817 
818 	if (pd->of_netdev) {
819 		dev = pd->of_netdev;
820 		dev_hold(dev);
821 	} else {
822 		dev = dsa_dev_to_net_device(pd->netdev);
823 	}
824 	if (dev == NULL) {
825 		ret = -EPROBE_DEFER;
826 		goto out;
827 	}
828 
829 	if (dev->dsa_ptr != NULL) {
830 		dev_put(dev);
831 		ret = -EEXIST;
832 		goto out;
833 	}
834 
835 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
836 	if (dst == NULL) {
837 		dev_put(dev);
838 		ret = -ENOMEM;
839 		goto out;
840 	}
841 
842 	platform_set_drvdata(pdev, dst);
843 
844 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
845 	if (ret) {
846 		dev_put(dev);
847 		goto out;
848 	}
849 
850 	return 0;
851 
852 out:
853 	dsa_of_remove(&pdev->dev);
854 
855 	return ret;
856 }
857 
858 static void dsa_remove_dst(struct dsa_switch_tree *dst)
859 {
860 	int i;
861 
862 	dst->master_netdev->dsa_ptr = NULL;
863 
864 	/* If we used a tagging format that doesn't have an ethertype
865 	 * field, make sure that all packets from this point get sent
866 	 * without the tag and go through the regular receive path.
867 	 */
868 	wmb();
869 
870 	for (i = 0; i < dst->pd->nr_chips; i++) {
871 		struct dsa_switch *ds = dst->ds[i];
872 
873 		if (ds)
874 			dsa_switch_destroy(ds);
875 	}
876 
877 	dsa_cpu_port_ethtool_restore(dst->cpu_switch);
878 
879 	dev_put(dst->master_netdev);
880 }
881 
882 static int dsa_remove(struct platform_device *pdev)
883 {
884 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
885 
886 	dsa_remove_dst(dst);
887 	dsa_of_remove(&pdev->dev);
888 
889 	return 0;
890 }
891 
892 static void dsa_shutdown(struct platform_device *pdev)
893 {
894 }
895 
896 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
897 			  struct packet_type *pt, struct net_device *orig_dev)
898 {
899 	struct dsa_switch_tree *dst = dev->dsa_ptr;
900 
901 	if (unlikely(dst == NULL)) {
902 		kfree_skb(skb);
903 		return 0;
904 	}
905 
906 	return dst->rcv(skb, dev, pt, orig_dev);
907 }
908 
909 static struct packet_type dsa_pack_type __read_mostly = {
910 	.type	= cpu_to_be16(ETH_P_XDSA),
911 	.func	= dsa_switch_rcv,
912 };
913 
914 #ifdef CONFIG_PM_SLEEP
915 static int dsa_suspend(struct device *d)
916 {
917 	struct platform_device *pdev = to_platform_device(d);
918 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
919 	int i, ret = 0;
920 
921 	for (i = 0; i < dst->pd->nr_chips; i++) {
922 		struct dsa_switch *ds = dst->ds[i];
923 
924 		if (ds != NULL)
925 			ret = dsa_switch_suspend(ds);
926 	}
927 
928 	return ret;
929 }
930 
931 static int dsa_resume(struct device *d)
932 {
933 	struct platform_device *pdev = to_platform_device(d);
934 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
935 	int i, ret = 0;
936 
937 	for (i = 0; i < dst->pd->nr_chips; i++) {
938 		struct dsa_switch *ds = dst->ds[i];
939 
940 		if (ds != NULL)
941 			ret = dsa_switch_resume(ds);
942 	}
943 
944 	return ret;
945 }
946 #endif
947 
948 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
949 
950 static const struct of_device_id dsa_of_match_table[] = {
951 	{ .compatible = "marvell,dsa", },
952 	{}
953 };
954 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
955 
956 static struct platform_driver dsa_driver = {
957 	.probe		= dsa_probe,
958 	.remove		= dsa_remove,
959 	.shutdown	= dsa_shutdown,
960 	.driver = {
961 		.name	= "dsa",
962 		.of_match_table = dsa_of_match_table,
963 		.pm	= &dsa_pm_ops,
964 	},
965 };
966 
967 static int __init dsa_init_module(void)
968 {
969 	int rc;
970 
971 	rc = dsa_slave_register_notifier();
972 	if (rc)
973 		return rc;
974 
975 	rc = platform_driver_register(&dsa_driver);
976 	if (rc)
977 		return rc;
978 
979 	dev_add_pack(&dsa_pack_type);
980 
981 	return 0;
982 }
983 module_init(dsa_init_module);
984 
985 static void __exit dsa_cleanup_module(void)
986 {
987 	dsa_slave_unregister_notifier();
988 	dev_remove_pack(&dsa_pack_type);
989 	platform_driver_unregister(&dsa_driver);
990 }
991 module_exit(dsa_cleanup_module);
992 
993 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
994 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
995 MODULE_LICENSE("GPL");
996 MODULE_ALIAS("platform:dsa");
997