xref: /linux/net/dsa/dsa.c (revision 182c2909e22d8a3ec39f8a4530fa19867cbd989b)
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/ctype.h>
13 #include <linux/device.h>
14 #include <linux/hwmon.h>
15 #include <linux/list.h>
16 #include <linux/platform_device.h>
17 #include <linux/slab.h>
18 #include <linux/module.h>
19 #include <net/dsa.h>
20 #include <linux/of.h>
21 #include <linux/of_mdio.h>
22 #include <linux/of_platform.h>
23 #include <linux/of_net.h>
24 #include <linux/of_gpio.h>
25 #include <linux/sysfs.h>
26 #include <linux/phy_fixed.h>
27 #include <linux/gpio/consumer.h>
28 #include "dsa_priv.h"
29 
30 char dsa_driver_version[] = "0.1";
31 
32 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
33 					    struct net_device *dev)
34 {
35 	/* Just return the original SKB */
36 	return skb;
37 }
38 
39 static const struct dsa_device_ops none_ops = {
40 	.xmit	= dsa_slave_notag_xmit,
41 	.rcv	= NULL,
42 };
43 
44 const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
45 #ifdef CONFIG_NET_DSA_TAG_DSA
46 	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
47 #endif
48 #ifdef CONFIG_NET_DSA_TAG_EDSA
49 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
50 #endif
51 #ifdef CONFIG_NET_DSA_TAG_TRAILER
52 	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
53 #endif
54 #ifdef CONFIG_NET_DSA_TAG_BRCM
55 	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
56 #endif
57 #ifdef CONFIG_NET_DSA_TAG_QCA
58 	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
59 #endif
60 	[DSA_TAG_PROTO_NONE] = &none_ops,
61 };
62 
63 /* switch driver registration ***********************************************/
64 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
65 static LIST_HEAD(dsa_switch_drivers);
66 
67 void register_switch_driver(struct dsa_switch_ops *ops)
68 {
69 	mutex_lock(&dsa_switch_drivers_mutex);
70 	list_add_tail(&ops->list, &dsa_switch_drivers);
71 	mutex_unlock(&dsa_switch_drivers_mutex);
72 }
73 EXPORT_SYMBOL_GPL(register_switch_driver);
74 
75 void unregister_switch_driver(struct dsa_switch_ops *ops)
76 {
77 	mutex_lock(&dsa_switch_drivers_mutex);
78 	list_del_init(&ops->list);
79 	mutex_unlock(&dsa_switch_drivers_mutex);
80 }
81 EXPORT_SYMBOL_GPL(unregister_switch_driver);
82 
83 static struct dsa_switch_ops *
84 dsa_switch_probe(struct device *parent, struct device *host_dev, int sw_addr,
85 		 const char **_name, void **priv)
86 {
87 	struct dsa_switch_ops *ret;
88 	struct list_head *list;
89 	const char *name;
90 
91 	ret = NULL;
92 	name = NULL;
93 
94 	mutex_lock(&dsa_switch_drivers_mutex);
95 	list_for_each(list, &dsa_switch_drivers) {
96 		struct dsa_switch_ops *ops;
97 
98 		ops = list_entry(list, struct dsa_switch_ops, list);
99 
100 		name = ops->probe(parent, host_dev, sw_addr, priv);
101 		if (name != NULL) {
102 			ret = ops;
103 			break;
104 		}
105 	}
106 	mutex_unlock(&dsa_switch_drivers_mutex);
107 
108 	*_name = name;
109 
110 	return ret;
111 }
112 
113 /* hwmon support ************************************************************/
114 
115 #ifdef CONFIG_NET_DSA_HWMON
116 
117 static ssize_t temp1_input_show(struct device *dev,
118 				struct device_attribute *attr, char *buf)
119 {
120 	struct dsa_switch *ds = dev_get_drvdata(dev);
121 	int temp, ret;
122 
123 	ret = ds->ops->get_temp(ds, &temp);
124 	if (ret < 0)
125 		return ret;
126 
127 	return sprintf(buf, "%d\n", temp * 1000);
128 }
129 static DEVICE_ATTR_RO(temp1_input);
130 
131 static ssize_t temp1_max_show(struct device *dev,
132 			      struct device_attribute *attr, char *buf)
133 {
134 	struct dsa_switch *ds = dev_get_drvdata(dev);
135 	int temp, ret;
136 
137 	ret = ds->ops->get_temp_limit(ds, &temp);
138 	if (ret < 0)
139 		return ret;
140 
141 	return sprintf(buf, "%d\n", temp * 1000);
142 }
143 
144 static ssize_t temp1_max_store(struct device *dev,
145 			       struct device_attribute *attr, const char *buf,
146 			       size_t count)
147 {
148 	struct dsa_switch *ds = dev_get_drvdata(dev);
149 	int temp, ret;
150 
151 	ret = kstrtoint(buf, 0, &temp);
152 	if (ret < 0)
153 		return ret;
154 
155 	ret = ds->ops->set_temp_limit(ds, DIV_ROUND_CLOSEST(temp, 1000));
156 	if (ret < 0)
157 		return ret;
158 
159 	return count;
160 }
161 static DEVICE_ATTR_RW(temp1_max);
162 
163 static ssize_t temp1_max_alarm_show(struct device *dev,
164 				    struct device_attribute *attr, char *buf)
165 {
166 	struct dsa_switch *ds = dev_get_drvdata(dev);
167 	bool alarm;
168 	int ret;
169 
170 	ret = ds->ops->get_temp_alarm(ds, &alarm);
171 	if (ret < 0)
172 		return ret;
173 
174 	return sprintf(buf, "%d\n", alarm);
175 }
176 static DEVICE_ATTR_RO(temp1_max_alarm);
177 
178 static struct attribute *dsa_hwmon_attrs[] = {
179 	&dev_attr_temp1_input.attr,	/* 0 */
180 	&dev_attr_temp1_max.attr,	/* 1 */
181 	&dev_attr_temp1_max_alarm.attr,	/* 2 */
182 	NULL
183 };
184 
185 static umode_t dsa_hwmon_attrs_visible(struct kobject *kobj,
186 				       struct attribute *attr, int index)
187 {
188 	struct device *dev = container_of(kobj, struct device, kobj);
189 	struct dsa_switch *ds = dev_get_drvdata(dev);
190 	struct dsa_switch_ops *ops = ds->ops;
191 	umode_t mode = attr->mode;
192 
193 	if (index == 1) {
194 		if (!ops->get_temp_limit)
195 			mode = 0;
196 		else if (!ops->set_temp_limit)
197 			mode &= ~S_IWUSR;
198 	} else if (index == 2 && !ops->get_temp_alarm) {
199 		mode = 0;
200 	}
201 	return mode;
202 }
203 
204 static const struct attribute_group dsa_hwmon_group = {
205 	.attrs = dsa_hwmon_attrs,
206 	.is_visible = dsa_hwmon_attrs_visible,
207 };
208 __ATTRIBUTE_GROUPS(dsa_hwmon);
209 
210 #endif /* CONFIG_NET_DSA_HWMON */
211 
212 /* basic switch operations **************************************************/
213 int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct device *dev,
214 		      struct device_node *port_dn, int port)
215 {
216 	struct phy_device *phydev;
217 	int ret, mode;
218 
219 	if (of_phy_is_fixed_link(port_dn)) {
220 		ret = of_phy_register_fixed_link(port_dn);
221 		if (ret) {
222 			dev_err(dev, "failed to register fixed PHY\n");
223 			return ret;
224 		}
225 		phydev = of_phy_find_device(port_dn);
226 
227 		mode = of_get_phy_mode(port_dn);
228 		if (mode < 0)
229 			mode = PHY_INTERFACE_MODE_NA;
230 		phydev->interface = mode;
231 
232 		genphy_config_init(phydev);
233 		genphy_read_status(phydev);
234 		if (ds->ops->adjust_link)
235 			ds->ops->adjust_link(ds, port, phydev);
236 
237 		put_device(&phydev->mdio.dev);
238 	}
239 
240 	return 0;
241 }
242 
243 static int dsa_cpu_dsa_setups(struct dsa_switch *ds, struct device *dev)
244 {
245 	struct device_node *port_dn;
246 	int ret, port;
247 
248 	for (port = 0; port < DSA_MAX_PORTS; port++) {
249 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
250 			continue;
251 
252 		port_dn = ds->ports[port].dn;
253 		ret = dsa_cpu_dsa_setup(ds, dev, port_dn, port);
254 		if (ret)
255 			return ret;
256 	}
257 	return 0;
258 }
259 
260 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
261 {
262 	const struct dsa_device_ops *ops;
263 
264 	if (tag_protocol >= DSA_TAG_LAST)
265 		return ERR_PTR(-EINVAL);
266 	ops = dsa_device_ops[tag_protocol];
267 
268 	if (!ops)
269 		return ERR_PTR(-ENOPROTOOPT);
270 
271 	return ops;
272 }
273 
274 int dsa_cpu_port_ethtool_setup(struct dsa_switch *ds)
275 {
276 	struct net_device *master;
277 	struct ethtool_ops *cpu_ops;
278 
279 	master = ds->dst->master_netdev;
280 	if (ds->master_netdev)
281 		master = ds->master_netdev;
282 
283 	cpu_ops = devm_kzalloc(ds->dev, sizeof(*cpu_ops), GFP_KERNEL);
284 	if (!cpu_ops)
285 		return -ENOMEM;
286 
287 	memcpy(&ds->dst->master_ethtool_ops, master->ethtool_ops,
288 	       sizeof(struct ethtool_ops));
289 	ds->dst->master_orig_ethtool_ops = master->ethtool_ops;
290 	memcpy(cpu_ops, &ds->dst->master_ethtool_ops,
291 	       sizeof(struct ethtool_ops));
292 	dsa_cpu_port_ethtool_init(cpu_ops);
293 	master->ethtool_ops = cpu_ops;
294 
295 	return 0;
296 }
297 
298 void dsa_cpu_port_ethtool_restore(struct dsa_switch *ds)
299 {
300 	struct net_device *master;
301 
302 	master = ds->dst->master_netdev;
303 	if (ds->master_netdev)
304 		master = ds->master_netdev;
305 
306 	master->ethtool_ops = ds->dst->master_orig_ethtool_ops;
307 }
308 
309 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
310 {
311 	struct dsa_switch_ops *ops = ds->ops;
312 	struct dsa_switch_tree *dst = ds->dst;
313 	struct dsa_chip_data *cd = ds->cd;
314 	bool valid_name_found = false;
315 	int index = ds->index;
316 	int i, ret;
317 
318 	/*
319 	 * Validate supplied switch configuration.
320 	 */
321 	for (i = 0; i < DSA_MAX_PORTS; i++) {
322 		char *name;
323 
324 		name = cd->port_names[i];
325 		if (name == NULL)
326 			continue;
327 
328 		if (!strcmp(name, "cpu")) {
329 			if (dst->cpu_switch != -1) {
330 				netdev_err(dst->master_netdev,
331 					   "multiple cpu ports?!\n");
332 				ret = -EINVAL;
333 				goto out;
334 			}
335 			dst->cpu_switch = index;
336 			dst->cpu_port = i;
337 			ds->cpu_port_mask |= 1 << i;
338 		} else if (!strcmp(name, "dsa")) {
339 			ds->dsa_port_mask |= 1 << i;
340 		} else {
341 			ds->enabled_port_mask |= 1 << i;
342 		}
343 		valid_name_found = true;
344 	}
345 
346 	if (!valid_name_found && i == DSA_MAX_PORTS) {
347 		ret = -EINVAL;
348 		goto out;
349 	}
350 
351 	/* Make the built-in MII bus mask match the number of ports,
352 	 * switch drivers can override this later
353 	 */
354 	ds->phys_mii_mask = ds->enabled_port_mask;
355 
356 	/*
357 	 * If the CPU connects to this switch, set the switch tree
358 	 * tagging protocol to the preferred tagging format of this
359 	 * switch.
360 	 */
361 	if (dst->cpu_switch == index) {
362 		enum dsa_tag_protocol tag_protocol;
363 
364 		tag_protocol = ops->get_tag_protocol(ds);
365 		dst->tag_ops = dsa_resolve_tag_protocol(tag_protocol);
366 		if (IS_ERR(dst->tag_ops)) {
367 			ret = PTR_ERR(dst->tag_ops);
368 			goto out;
369 		}
370 
371 		dst->rcv = dst->tag_ops->rcv;
372 	}
373 
374 	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
375 
376 	/*
377 	 * Do basic register setup.
378 	 */
379 	ret = ops->setup(ds);
380 	if (ret < 0)
381 		goto out;
382 
383 	if (ops->set_addr) {
384 		ret = ops->set_addr(ds, dst->master_netdev->dev_addr);
385 		if (ret < 0)
386 			goto out;
387 	}
388 
389 	if (!ds->slave_mii_bus && ops->phy_read) {
390 		ds->slave_mii_bus = devm_mdiobus_alloc(parent);
391 		if (!ds->slave_mii_bus) {
392 			ret = -ENOMEM;
393 			goto out;
394 		}
395 		dsa_slave_mii_bus_init(ds);
396 
397 		ret = mdiobus_register(ds->slave_mii_bus);
398 		if (ret < 0)
399 			goto out;
400 	}
401 
402 	/*
403 	 * Create network devices for physical switch ports.
404 	 */
405 	for (i = 0; i < DSA_MAX_PORTS; i++) {
406 		ds->ports[i].dn = cd->port_dn[i];
407 
408 		if (!(ds->enabled_port_mask & (1 << i)))
409 			continue;
410 
411 		ret = dsa_slave_create(ds, parent, i, cd->port_names[i]);
412 		if (ret < 0) {
413 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
414 				   index, i, cd->port_names[i], ret);
415 			ret = 0;
416 		}
417 	}
418 
419 	/* Perform configuration of the CPU and DSA ports */
420 	ret = dsa_cpu_dsa_setups(ds, parent);
421 	if (ret < 0) {
422 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
423 			   index);
424 		ret = 0;
425 	}
426 
427 	ret = dsa_cpu_port_ethtool_setup(ds);
428 	if (ret)
429 		return ret;
430 
431 #ifdef CONFIG_NET_DSA_HWMON
432 	/* If the switch provides a temperature sensor,
433 	 * register with hardware monitoring subsystem.
434 	 * Treat registration error as non-fatal and ignore it.
435 	 */
436 	if (ops->get_temp) {
437 		const char *netname = netdev_name(dst->master_netdev);
438 		char hname[IFNAMSIZ + 1];
439 		int i, j;
440 
441 		/* Create valid hwmon 'name' attribute */
442 		for (i = j = 0; i < IFNAMSIZ && netname[i]; i++) {
443 			if (isalnum(netname[i]))
444 				hname[j++] = netname[i];
445 		}
446 		hname[j] = '\0';
447 		scnprintf(ds->hwmon_name, sizeof(ds->hwmon_name), "%s_dsa%d",
448 			  hname, index);
449 		ds->hwmon_dev = hwmon_device_register_with_groups(NULL,
450 					ds->hwmon_name, ds, dsa_hwmon_groups);
451 		if (IS_ERR(ds->hwmon_dev))
452 			ds->hwmon_dev = NULL;
453 	}
454 #endif /* CONFIG_NET_DSA_HWMON */
455 
456 	return ret;
457 
458 out:
459 	return ret;
460 }
461 
462 static struct dsa_switch *
463 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
464 		 struct device *parent, struct device *host_dev)
465 {
466 	struct dsa_chip_data *cd = dst->pd->chip + index;
467 	struct dsa_switch_ops *ops;
468 	struct dsa_switch *ds;
469 	int ret;
470 	const char *name;
471 	void *priv;
472 
473 	/*
474 	 * Probe for switch model.
475 	 */
476 	ops = dsa_switch_probe(parent, host_dev, cd->sw_addr, &name, &priv);
477 	if (!ops) {
478 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
479 			   index);
480 		return ERR_PTR(-EINVAL);
481 	}
482 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
483 		    index, name);
484 
485 
486 	/*
487 	 * Allocate and initialise switch state.
488 	 */
489 	ds = devm_kzalloc(parent, sizeof(*ds), GFP_KERNEL);
490 	if (ds == NULL)
491 		return ERR_PTR(-ENOMEM);
492 
493 	ds->dst = dst;
494 	ds->index = index;
495 	ds->cd = cd;
496 	ds->ops = ops;
497 	ds->priv = priv;
498 	ds->dev = parent;
499 
500 	ret = dsa_switch_setup_one(ds, parent);
501 	if (ret)
502 		return ERR_PTR(ret);
503 
504 	return ds;
505 }
506 
507 void dsa_cpu_dsa_destroy(struct device_node *port_dn)
508 {
509 	if (of_phy_is_fixed_link(port_dn))
510 		of_phy_deregister_fixed_link(port_dn);
511 }
512 
513 static void dsa_switch_destroy(struct dsa_switch *ds)
514 {
515 	int port;
516 
517 #ifdef CONFIG_NET_DSA_HWMON
518 	if (ds->hwmon_dev)
519 		hwmon_device_unregister(ds->hwmon_dev);
520 #endif
521 
522 	/* Destroy network devices for physical switch ports. */
523 	for (port = 0; port < DSA_MAX_PORTS; port++) {
524 		if (!(ds->enabled_port_mask & (1 << port)))
525 			continue;
526 
527 		if (!ds->ports[port].netdev)
528 			continue;
529 
530 		dsa_slave_destroy(ds->ports[port].netdev);
531 	}
532 
533 	/* Disable configuration of the CPU and DSA ports */
534 	for (port = 0; port < DSA_MAX_PORTS; port++) {
535 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
536 			continue;
537 		dsa_cpu_dsa_destroy(ds->ports[port].dn);
538 
539 		/* Clearing a bit which is not set does no harm */
540 		ds->cpu_port_mask |= ~(1 << port);
541 		ds->dsa_port_mask |= ~(1 << port);
542 	}
543 
544 	if (ds->slave_mii_bus && ds->ops->phy_read)
545 		mdiobus_unregister(ds->slave_mii_bus);
546 }
547 
548 #ifdef CONFIG_PM_SLEEP
549 int dsa_switch_suspend(struct dsa_switch *ds)
550 {
551 	int i, ret = 0;
552 
553 	/* Suspend slave network devices */
554 	for (i = 0; i < DSA_MAX_PORTS; i++) {
555 		if (!dsa_is_port_initialized(ds, i))
556 			continue;
557 
558 		ret = dsa_slave_suspend(ds->ports[i].netdev);
559 		if (ret)
560 			return ret;
561 	}
562 
563 	if (ds->ops->suspend)
564 		ret = ds->ops->suspend(ds);
565 
566 	return ret;
567 }
568 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
569 
570 int dsa_switch_resume(struct dsa_switch *ds)
571 {
572 	int i, ret = 0;
573 
574 	if (ds->ops->resume)
575 		ret = ds->ops->resume(ds);
576 
577 	if (ret)
578 		return ret;
579 
580 	/* Resume slave network devices */
581 	for (i = 0; i < DSA_MAX_PORTS; i++) {
582 		if (!dsa_is_port_initialized(ds, i))
583 			continue;
584 
585 		ret = dsa_slave_resume(ds->ports[i].netdev);
586 		if (ret)
587 			return ret;
588 	}
589 
590 	return 0;
591 }
592 EXPORT_SYMBOL_GPL(dsa_switch_resume);
593 #endif
594 
595 /* platform driver init and cleanup *****************************************/
596 static int dev_is_class(struct device *dev, void *class)
597 {
598 	if (dev->class != NULL && !strcmp(dev->class->name, class))
599 		return 1;
600 
601 	return 0;
602 }
603 
604 static struct device *dev_find_class(struct device *parent, char *class)
605 {
606 	if (dev_is_class(parent, class)) {
607 		get_device(parent);
608 		return parent;
609 	}
610 
611 	return device_find_child(parent, class, dev_is_class);
612 }
613 
614 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
615 {
616 	struct device *d;
617 
618 	d = dev_find_class(dev, "mdio_bus");
619 	if (d != NULL) {
620 		struct mii_bus *bus;
621 
622 		bus = to_mii_bus(d);
623 		put_device(d);
624 
625 		return bus;
626 	}
627 
628 	return NULL;
629 }
630 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
631 
632 static struct net_device *dev_to_net_device(struct device *dev)
633 {
634 	struct device *d;
635 
636 	d = dev_find_class(dev, "net");
637 	if (d != NULL) {
638 		struct net_device *nd;
639 
640 		nd = to_net_dev(d);
641 		dev_hold(nd);
642 		put_device(d);
643 
644 		return nd;
645 	}
646 
647 	return NULL;
648 }
649 
650 #ifdef CONFIG_OF
651 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
652 					struct dsa_chip_data *cd,
653 					int chip_index, int port_index,
654 					struct device_node *link)
655 {
656 	const __be32 *reg;
657 	int link_sw_addr;
658 	struct device_node *parent_sw;
659 	int len;
660 
661 	parent_sw = of_get_parent(link);
662 	if (!parent_sw)
663 		return -EINVAL;
664 
665 	reg = of_get_property(parent_sw, "reg", &len);
666 	if (!reg || (len != sizeof(*reg) * 2))
667 		return -EINVAL;
668 
669 	/*
670 	 * Get the destination switch number from the second field of its 'reg'
671 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
672 	 */
673 	link_sw_addr = be32_to_cpup(reg + 1);
674 
675 	if (link_sw_addr >= pd->nr_chips)
676 		return -EINVAL;
677 
678 	cd->rtable[link_sw_addr] = port_index;
679 
680 	return 0;
681 }
682 
683 static int dsa_of_probe_links(struct dsa_platform_data *pd,
684 			      struct dsa_chip_data *cd,
685 			      int chip_index, int port_index,
686 			      struct device_node *port,
687 			      const char *port_name)
688 {
689 	struct device_node *link;
690 	int link_index;
691 	int ret;
692 
693 	for (link_index = 0;; link_index++) {
694 		link = of_parse_phandle(port, "link", link_index);
695 		if (!link)
696 			break;
697 
698 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
699 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
700 							 port_index, link);
701 			if (ret)
702 				return ret;
703 		}
704 	}
705 	return 0;
706 }
707 
708 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
709 {
710 	int i;
711 	int port_index;
712 
713 	for (i = 0; i < pd->nr_chips; i++) {
714 		port_index = 0;
715 		while (port_index < DSA_MAX_PORTS) {
716 			kfree(pd->chip[i].port_names[port_index]);
717 			port_index++;
718 		}
719 
720 		/* Drop our reference to the MDIO bus device */
721 		if (pd->chip[i].host_dev)
722 			put_device(pd->chip[i].host_dev);
723 	}
724 	kfree(pd->chip);
725 }
726 
727 static int dsa_of_probe(struct device *dev)
728 {
729 	struct device_node *np = dev->of_node;
730 	struct device_node *child, *mdio, *ethernet, *port;
731 	struct mii_bus *mdio_bus, *mdio_bus_switch;
732 	struct net_device *ethernet_dev;
733 	struct dsa_platform_data *pd;
734 	struct dsa_chip_data *cd;
735 	const char *port_name;
736 	int chip_index, port_index;
737 	const unsigned int *sw_addr, *port_reg;
738 	u32 eeprom_len;
739 	int ret;
740 
741 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
742 	if (!mdio)
743 		return -EINVAL;
744 
745 	mdio_bus = of_mdio_find_bus(mdio);
746 	if (!mdio_bus)
747 		return -EPROBE_DEFER;
748 
749 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
750 	if (!ethernet) {
751 		ret = -EINVAL;
752 		goto out_put_mdio;
753 	}
754 
755 	ethernet_dev = of_find_net_device_by_node(ethernet);
756 	if (!ethernet_dev) {
757 		ret = -EPROBE_DEFER;
758 		goto out_put_mdio;
759 	}
760 
761 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
762 	if (!pd) {
763 		ret = -ENOMEM;
764 		goto out_put_ethernet;
765 	}
766 
767 	dev->platform_data = pd;
768 	pd->of_netdev = ethernet_dev;
769 	pd->nr_chips = of_get_available_child_count(np);
770 	if (pd->nr_chips > DSA_MAX_SWITCHES)
771 		pd->nr_chips = DSA_MAX_SWITCHES;
772 
773 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
774 			   GFP_KERNEL);
775 	if (!pd->chip) {
776 		ret = -ENOMEM;
777 		goto out_free;
778 	}
779 
780 	chip_index = -1;
781 	for_each_available_child_of_node(np, child) {
782 		int i;
783 
784 		chip_index++;
785 		cd = &pd->chip[chip_index];
786 
787 		cd->of_node = child;
788 
789 		/* Initialize the routing table */
790 		for (i = 0; i < DSA_MAX_SWITCHES; ++i)
791 			cd->rtable[i] = DSA_RTABLE_NONE;
792 
793 		/* When assigning the host device, increment its refcount */
794 		cd->host_dev = get_device(&mdio_bus->dev);
795 
796 		sw_addr = of_get_property(child, "reg", NULL);
797 		if (!sw_addr)
798 			continue;
799 
800 		cd->sw_addr = be32_to_cpup(sw_addr);
801 		if (cd->sw_addr >= PHY_MAX_ADDR)
802 			continue;
803 
804 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
805 			cd->eeprom_len = eeprom_len;
806 
807 		mdio = of_parse_phandle(child, "mii-bus", 0);
808 		if (mdio) {
809 			mdio_bus_switch = of_mdio_find_bus(mdio);
810 			if (!mdio_bus_switch) {
811 				ret = -EPROBE_DEFER;
812 				goto out_free_chip;
813 			}
814 
815 			/* Drop the mdio_bus device ref, replacing the host
816 			 * device with the mdio_bus_switch device, keeping
817 			 * the refcount from of_mdio_find_bus() above.
818 			 */
819 			put_device(cd->host_dev);
820 			cd->host_dev = &mdio_bus_switch->dev;
821 		}
822 
823 		for_each_available_child_of_node(child, port) {
824 			port_reg = of_get_property(port, "reg", NULL);
825 			if (!port_reg)
826 				continue;
827 
828 			port_index = be32_to_cpup(port_reg);
829 			if (port_index >= DSA_MAX_PORTS)
830 				break;
831 
832 			port_name = of_get_property(port, "label", NULL);
833 			if (!port_name)
834 				continue;
835 
836 			cd->port_dn[port_index] = port;
837 
838 			cd->port_names[port_index] = kstrdup(port_name,
839 					GFP_KERNEL);
840 			if (!cd->port_names[port_index]) {
841 				ret = -ENOMEM;
842 				goto out_free_chip;
843 			}
844 
845 			ret = dsa_of_probe_links(pd, cd, chip_index,
846 						 port_index, port, port_name);
847 			if (ret)
848 				goto out_free_chip;
849 
850 		}
851 	}
852 
853 	/* The individual chips hold their own refcount on the mdio bus,
854 	 * so drop ours */
855 	put_device(&mdio_bus->dev);
856 
857 	return 0;
858 
859 out_free_chip:
860 	dsa_of_free_platform_data(pd);
861 out_free:
862 	kfree(pd);
863 	dev->platform_data = NULL;
864 out_put_ethernet:
865 	put_device(&ethernet_dev->dev);
866 out_put_mdio:
867 	put_device(&mdio_bus->dev);
868 	return ret;
869 }
870 
871 static void dsa_of_remove(struct device *dev)
872 {
873 	struct dsa_platform_data *pd = dev->platform_data;
874 
875 	if (!dev->of_node)
876 		return;
877 
878 	dsa_of_free_platform_data(pd);
879 	put_device(&pd->of_netdev->dev);
880 	kfree(pd);
881 }
882 #else
883 static inline int dsa_of_probe(struct device *dev)
884 {
885 	return 0;
886 }
887 
888 static inline void dsa_of_remove(struct device *dev)
889 {
890 }
891 #endif
892 
893 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
894 			 struct device *parent, struct dsa_platform_data *pd)
895 {
896 	int i;
897 	unsigned configured = 0;
898 
899 	dst->pd = pd;
900 	dst->master_netdev = dev;
901 	dst->cpu_switch = -1;
902 	dst->cpu_port = -1;
903 
904 	for (i = 0; i < pd->nr_chips; i++) {
905 		struct dsa_switch *ds;
906 
907 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
908 		if (IS_ERR(ds)) {
909 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
910 				   i, PTR_ERR(ds));
911 			continue;
912 		}
913 
914 		dst->ds[i] = ds;
915 
916 		++configured;
917 	}
918 
919 	/*
920 	 * If no switch was found, exit cleanly
921 	 */
922 	if (!configured)
923 		return -EPROBE_DEFER;
924 
925 	/*
926 	 * If we use a tagging format that doesn't have an ethertype
927 	 * field, make sure that all packets from this point on get
928 	 * sent to the tag format's receive function.
929 	 */
930 	wmb();
931 	dev->dsa_ptr = (void *)dst;
932 
933 	return 0;
934 }
935 
936 static int dsa_probe(struct platform_device *pdev)
937 {
938 	struct dsa_platform_data *pd = pdev->dev.platform_data;
939 	struct net_device *dev;
940 	struct dsa_switch_tree *dst;
941 	int ret;
942 
943 	pr_notice_once("Distributed Switch Architecture driver version %s\n",
944 		       dsa_driver_version);
945 
946 	if (pdev->dev.of_node) {
947 		ret = dsa_of_probe(&pdev->dev);
948 		if (ret)
949 			return ret;
950 
951 		pd = pdev->dev.platform_data;
952 	}
953 
954 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
955 		return -EINVAL;
956 
957 	if (pd->of_netdev) {
958 		dev = pd->of_netdev;
959 		dev_hold(dev);
960 	} else {
961 		dev = dev_to_net_device(pd->netdev);
962 	}
963 	if (dev == NULL) {
964 		ret = -EPROBE_DEFER;
965 		goto out;
966 	}
967 
968 	if (dev->dsa_ptr != NULL) {
969 		dev_put(dev);
970 		ret = -EEXIST;
971 		goto out;
972 	}
973 
974 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
975 	if (dst == NULL) {
976 		dev_put(dev);
977 		ret = -ENOMEM;
978 		goto out;
979 	}
980 
981 	platform_set_drvdata(pdev, dst);
982 
983 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
984 	if (ret) {
985 		dev_put(dev);
986 		goto out;
987 	}
988 
989 	return 0;
990 
991 out:
992 	dsa_of_remove(&pdev->dev);
993 
994 	return ret;
995 }
996 
997 static void dsa_remove_dst(struct dsa_switch_tree *dst)
998 {
999 	int i;
1000 
1001 	dst->master_netdev->dsa_ptr = NULL;
1002 
1003 	/* If we used a tagging format that doesn't have an ethertype
1004 	 * field, make sure that all packets from this point get sent
1005 	 * without the tag and go through the regular receive path.
1006 	 */
1007 	wmb();
1008 
1009 	for (i = 0; i < dst->pd->nr_chips; i++) {
1010 		struct dsa_switch *ds = dst->ds[i];
1011 
1012 		if (ds)
1013 			dsa_switch_destroy(ds);
1014 	}
1015 
1016 	dsa_cpu_port_ethtool_restore(dst->ds[0]);
1017 
1018 	dev_put(dst->master_netdev);
1019 }
1020 
1021 static int dsa_remove(struct platform_device *pdev)
1022 {
1023 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1024 
1025 	dsa_remove_dst(dst);
1026 	dsa_of_remove(&pdev->dev);
1027 
1028 	return 0;
1029 }
1030 
1031 static void dsa_shutdown(struct platform_device *pdev)
1032 {
1033 }
1034 
1035 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
1036 			  struct packet_type *pt, struct net_device *orig_dev)
1037 {
1038 	struct dsa_switch_tree *dst = dev->dsa_ptr;
1039 
1040 	if (unlikely(dst == NULL)) {
1041 		kfree_skb(skb);
1042 		return 0;
1043 	}
1044 
1045 	return dst->rcv(skb, dev, pt, orig_dev);
1046 }
1047 
1048 static struct packet_type dsa_pack_type __read_mostly = {
1049 	.type	= cpu_to_be16(ETH_P_XDSA),
1050 	.func	= dsa_switch_rcv,
1051 };
1052 
1053 static struct notifier_block dsa_netdevice_nb __read_mostly = {
1054 	.notifier_call	= dsa_slave_netdevice_event,
1055 };
1056 
1057 #ifdef CONFIG_PM_SLEEP
1058 static int dsa_suspend(struct device *d)
1059 {
1060 	struct platform_device *pdev = to_platform_device(d);
1061 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1062 	int i, ret = 0;
1063 
1064 	for (i = 0; i < dst->pd->nr_chips; i++) {
1065 		struct dsa_switch *ds = dst->ds[i];
1066 
1067 		if (ds != NULL)
1068 			ret = dsa_switch_suspend(ds);
1069 	}
1070 
1071 	return ret;
1072 }
1073 
1074 static int dsa_resume(struct device *d)
1075 {
1076 	struct platform_device *pdev = to_platform_device(d);
1077 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1078 	int i, ret = 0;
1079 
1080 	for (i = 0; i < dst->pd->nr_chips; i++) {
1081 		struct dsa_switch *ds = dst->ds[i];
1082 
1083 		if (ds != NULL)
1084 			ret = dsa_switch_resume(ds);
1085 	}
1086 
1087 	return ret;
1088 }
1089 #endif
1090 
1091 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
1092 
1093 static const struct of_device_id dsa_of_match_table[] = {
1094 	{ .compatible = "marvell,dsa", },
1095 	{}
1096 };
1097 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
1098 
1099 static struct platform_driver dsa_driver = {
1100 	.probe		= dsa_probe,
1101 	.remove		= dsa_remove,
1102 	.shutdown	= dsa_shutdown,
1103 	.driver = {
1104 		.name	= "dsa",
1105 		.of_match_table = dsa_of_match_table,
1106 		.pm	= &dsa_pm_ops,
1107 	},
1108 };
1109 
1110 static int __init dsa_init_module(void)
1111 {
1112 	int rc;
1113 
1114 	register_netdevice_notifier(&dsa_netdevice_nb);
1115 
1116 	rc = platform_driver_register(&dsa_driver);
1117 	if (rc)
1118 		return rc;
1119 
1120 	dev_add_pack(&dsa_pack_type);
1121 
1122 	return 0;
1123 }
1124 module_init(dsa_init_module);
1125 
1126 static void __exit dsa_cleanup_module(void)
1127 {
1128 	unregister_netdevice_notifier(&dsa_netdevice_nb);
1129 	dev_remove_pack(&dsa_pack_type);
1130 	platform_driver_unregister(&dsa_driver);
1131 }
1132 module_exit(dsa_cleanup_module);
1133 
1134 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
1135 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
1136 MODULE_LICENSE("GPL");
1137 MODULE_ALIAS("platform:dsa");
1138