xref: /openbmc/linux/net/dsa/dsa.c (revision 6dfcd296)
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 
238 	return 0;
239 }
240 
241 static int dsa_cpu_dsa_setups(struct dsa_switch *ds, struct device *dev)
242 {
243 	struct device_node *port_dn;
244 	int ret, port;
245 
246 	for (port = 0; port < DSA_MAX_PORTS; port++) {
247 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
248 			continue;
249 
250 		port_dn = ds->ports[port].dn;
251 		ret = dsa_cpu_dsa_setup(ds, dev, port_dn, port);
252 		if (ret)
253 			return ret;
254 	}
255 	return 0;
256 }
257 
258 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
259 {
260 	const struct dsa_device_ops *ops;
261 
262 	if (tag_protocol >= DSA_TAG_LAST)
263 		return ERR_PTR(-EINVAL);
264 	ops = dsa_device_ops[tag_protocol];
265 
266 	if (!ops)
267 		return ERR_PTR(-ENOPROTOOPT);
268 
269 	return ops;
270 }
271 
272 int dsa_cpu_port_ethtool_setup(struct dsa_switch *ds)
273 {
274 	struct net_device *master;
275 	struct ethtool_ops *cpu_ops;
276 
277 	master = ds->dst->master_netdev;
278 	if (ds->master_netdev)
279 		master = ds->master_netdev;
280 
281 	cpu_ops = devm_kzalloc(ds->dev, sizeof(*cpu_ops), GFP_KERNEL);
282 	if (!cpu_ops)
283 		return -ENOMEM;
284 
285 	memcpy(&ds->dst->master_ethtool_ops, master->ethtool_ops,
286 	       sizeof(struct ethtool_ops));
287 	ds->dst->master_orig_ethtool_ops = master->ethtool_ops;
288 	memcpy(cpu_ops, &ds->dst->master_ethtool_ops,
289 	       sizeof(struct ethtool_ops));
290 	dsa_cpu_port_ethtool_init(cpu_ops);
291 	master->ethtool_ops = cpu_ops;
292 
293 	return 0;
294 }
295 
296 void dsa_cpu_port_ethtool_restore(struct dsa_switch *ds)
297 {
298 	struct net_device *master;
299 
300 	master = ds->dst->master_netdev;
301 	if (ds->master_netdev)
302 		master = ds->master_netdev;
303 
304 	master->ethtool_ops = ds->dst->master_orig_ethtool_ops;
305 }
306 
307 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
308 {
309 	struct dsa_switch_ops *ops = ds->ops;
310 	struct dsa_switch_tree *dst = ds->dst;
311 	struct dsa_chip_data *cd = ds->cd;
312 	bool valid_name_found = false;
313 	int index = ds->index;
314 	int i, ret;
315 
316 	/*
317 	 * Validate supplied switch configuration.
318 	 */
319 	for (i = 0; i < DSA_MAX_PORTS; i++) {
320 		char *name;
321 
322 		name = cd->port_names[i];
323 		if (name == NULL)
324 			continue;
325 
326 		if (!strcmp(name, "cpu")) {
327 			if (dst->cpu_switch != -1) {
328 				netdev_err(dst->master_netdev,
329 					   "multiple cpu ports?!\n");
330 				ret = -EINVAL;
331 				goto out;
332 			}
333 			dst->cpu_switch = index;
334 			dst->cpu_port = i;
335 			ds->cpu_port_mask |= 1 << i;
336 		} else if (!strcmp(name, "dsa")) {
337 			ds->dsa_port_mask |= 1 << i;
338 		} else {
339 			ds->enabled_port_mask |= 1 << i;
340 		}
341 		valid_name_found = true;
342 	}
343 
344 	if (!valid_name_found && i == DSA_MAX_PORTS) {
345 		ret = -EINVAL;
346 		goto out;
347 	}
348 
349 	/* Make the built-in MII bus mask match the number of ports,
350 	 * switch drivers can override this later
351 	 */
352 	ds->phys_mii_mask = ds->enabled_port_mask;
353 
354 	/*
355 	 * If the CPU connects to this switch, set the switch tree
356 	 * tagging protocol to the preferred tagging format of this
357 	 * switch.
358 	 */
359 	if (dst->cpu_switch == index) {
360 		enum dsa_tag_protocol tag_protocol;
361 
362 		tag_protocol = ops->get_tag_protocol(ds);
363 		dst->tag_ops = dsa_resolve_tag_protocol(tag_protocol);
364 		if (IS_ERR(dst->tag_ops)) {
365 			ret = PTR_ERR(dst->tag_ops);
366 			goto out;
367 		}
368 
369 		dst->rcv = dst->tag_ops->rcv;
370 	}
371 
372 	memcpy(ds->rtable, cd->rtable, sizeof(ds->rtable));
373 
374 	/*
375 	 * Do basic register setup.
376 	 */
377 	ret = ops->setup(ds);
378 	if (ret < 0)
379 		goto out;
380 
381 	if (ops->set_addr) {
382 		ret = ops->set_addr(ds, dst->master_netdev->dev_addr);
383 		if (ret < 0)
384 			goto out;
385 	}
386 
387 	if (!ds->slave_mii_bus && ops->phy_read) {
388 		ds->slave_mii_bus = devm_mdiobus_alloc(parent);
389 		if (!ds->slave_mii_bus) {
390 			ret = -ENOMEM;
391 			goto out;
392 		}
393 		dsa_slave_mii_bus_init(ds);
394 
395 		ret = mdiobus_register(ds->slave_mii_bus);
396 		if (ret < 0)
397 			goto out;
398 	}
399 
400 	/*
401 	 * Create network devices for physical switch ports.
402 	 */
403 	for (i = 0; i < DSA_MAX_PORTS; i++) {
404 		ds->ports[i].dn = cd->port_dn[i];
405 
406 		if (!(ds->enabled_port_mask & (1 << i)))
407 			continue;
408 
409 		ret = dsa_slave_create(ds, parent, i, cd->port_names[i]);
410 		if (ret < 0) {
411 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
412 				   index, i, cd->port_names[i], ret);
413 			ret = 0;
414 		}
415 	}
416 
417 	/* Perform configuration of the CPU and DSA ports */
418 	ret = dsa_cpu_dsa_setups(ds, parent);
419 	if (ret < 0) {
420 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
421 			   index);
422 		ret = 0;
423 	}
424 
425 	ret = dsa_cpu_port_ethtool_setup(ds);
426 	if (ret)
427 		return ret;
428 
429 #ifdef CONFIG_NET_DSA_HWMON
430 	/* If the switch provides a temperature sensor,
431 	 * register with hardware monitoring subsystem.
432 	 * Treat registration error as non-fatal and ignore it.
433 	 */
434 	if (ops->get_temp) {
435 		const char *netname = netdev_name(dst->master_netdev);
436 		char hname[IFNAMSIZ + 1];
437 		int i, j;
438 
439 		/* Create valid hwmon 'name' attribute */
440 		for (i = j = 0; i < IFNAMSIZ && netname[i]; i++) {
441 			if (isalnum(netname[i]))
442 				hname[j++] = netname[i];
443 		}
444 		hname[j] = '\0';
445 		scnprintf(ds->hwmon_name, sizeof(ds->hwmon_name), "%s_dsa%d",
446 			  hname, index);
447 		ds->hwmon_dev = hwmon_device_register_with_groups(NULL,
448 					ds->hwmon_name, ds, dsa_hwmon_groups);
449 		if (IS_ERR(ds->hwmon_dev))
450 			ds->hwmon_dev = NULL;
451 	}
452 #endif /* CONFIG_NET_DSA_HWMON */
453 
454 	return ret;
455 
456 out:
457 	return ret;
458 }
459 
460 static struct dsa_switch *
461 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
462 		 struct device *parent, struct device *host_dev)
463 {
464 	struct dsa_chip_data *cd = dst->pd->chip + index;
465 	struct dsa_switch_ops *ops;
466 	struct dsa_switch *ds;
467 	int ret;
468 	const char *name;
469 	void *priv;
470 
471 	/*
472 	 * Probe for switch model.
473 	 */
474 	ops = dsa_switch_probe(parent, host_dev, cd->sw_addr, &name, &priv);
475 	if (!ops) {
476 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
477 			   index);
478 		return ERR_PTR(-EINVAL);
479 	}
480 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
481 		    index, name);
482 
483 
484 	/*
485 	 * Allocate and initialise switch state.
486 	 */
487 	ds = devm_kzalloc(parent, sizeof(*ds), GFP_KERNEL);
488 	if (ds == NULL)
489 		return ERR_PTR(-ENOMEM);
490 
491 	ds->dst = dst;
492 	ds->index = index;
493 	ds->cd = cd;
494 	ds->ops = ops;
495 	ds->priv = priv;
496 	ds->dev = parent;
497 
498 	ret = dsa_switch_setup_one(ds, parent);
499 	if (ret)
500 		return ERR_PTR(ret);
501 
502 	return ds;
503 }
504 
505 void dsa_cpu_dsa_destroy(struct device_node *port_dn)
506 {
507 	struct phy_device *phydev;
508 
509 	if (of_phy_is_fixed_link(port_dn)) {
510 		phydev = of_phy_find_device(port_dn);
511 		if (phydev) {
512 			phy_device_free(phydev);
513 			fixed_phy_unregister(phydev);
514 		}
515 	}
516 }
517 
518 static void dsa_switch_destroy(struct dsa_switch *ds)
519 {
520 	int port;
521 
522 #ifdef CONFIG_NET_DSA_HWMON
523 	if (ds->hwmon_dev)
524 		hwmon_device_unregister(ds->hwmon_dev);
525 #endif
526 
527 	/* Destroy network devices for physical switch ports. */
528 	for (port = 0; port < DSA_MAX_PORTS; port++) {
529 		if (!(ds->enabled_port_mask & (1 << port)))
530 			continue;
531 
532 		if (!ds->ports[port].netdev)
533 			continue;
534 
535 		dsa_slave_destroy(ds->ports[port].netdev);
536 	}
537 
538 	/* Disable configuration of the CPU and DSA ports */
539 	for (port = 0; port < DSA_MAX_PORTS; port++) {
540 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
541 			continue;
542 		dsa_cpu_dsa_destroy(ds->ports[port].dn);
543 
544 		/* Clearing a bit which is not set does no harm */
545 		ds->cpu_port_mask |= ~(1 << port);
546 		ds->dsa_port_mask |= ~(1 << port);
547 	}
548 
549 	if (ds->slave_mii_bus && ds->ops->phy_read)
550 		mdiobus_unregister(ds->slave_mii_bus);
551 }
552 
553 #ifdef CONFIG_PM_SLEEP
554 int dsa_switch_suspend(struct dsa_switch *ds)
555 {
556 	int i, ret = 0;
557 
558 	/* Suspend slave network devices */
559 	for (i = 0; i < DSA_MAX_PORTS; i++) {
560 		if (!dsa_is_port_initialized(ds, i))
561 			continue;
562 
563 		ret = dsa_slave_suspend(ds->ports[i].netdev);
564 		if (ret)
565 			return ret;
566 	}
567 
568 	if (ds->ops->suspend)
569 		ret = ds->ops->suspend(ds);
570 
571 	return ret;
572 }
573 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
574 
575 int dsa_switch_resume(struct dsa_switch *ds)
576 {
577 	int i, ret = 0;
578 
579 	if (ds->ops->resume)
580 		ret = ds->ops->resume(ds);
581 
582 	if (ret)
583 		return ret;
584 
585 	/* Resume slave network devices */
586 	for (i = 0; i < DSA_MAX_PORTS; i++) {
587 		if (!dsa_is_port_initialized(ds, i))
588 			continue;
589 
590 		ret = dsa_slave_resume(ds->ports[i].netdev);
591 		if (ret)
592 			return ret;
593 	}
594 
595 	return 0;
596 }
597 EXPORT_SYMBOL_GPL(dsa_switch_resume);
598 #endif
599 
600 /* platform driver init and cleanup *****************************************/
601 static int dev_is_class(struct device *dev, void *class)
602 {
603 	if (dev->class != NULL && !strcmp(dev->class->name, class))
604 		return 1;
605 
606 	return 0;
607 }
608 
609 static struct device *dev_find_class(struct device *parent, char *class)
610 {
611 	if (dev_is_class(parent, class)) {
612 		get_device(parent);
613 		return parent;
614 	}
615 
616 	return device_find_child(parent, class, dev_is_class);
617 }
618 
619 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
620 {
621 	struct device *d;
622 
623 	d = dev_find_class(dev, "mdio_bus");
624 	if (d != NULL) {
625 		struct mii_bus *bus;
626 
627 		bus = to_mii_bus(d);
628 		put_device(d);
629 
630 		return bus;
631 	}
632 
633 	return NULL;
634 }
635 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
636 
637 static struct net_device *dev_to_net_device(struct device *dev)
638 {
639 	struct device *d;
640 
641 	d = dev_find_class(dev, "net");
642 	if (d != NULL) {
643 		struct net_device *nd;
644 
645 		nd = to_net_dev(d);
646 		dev_hold(nd);
647 		put_device(d);
648 
649 		return nd;
650 	}
651 
652 	return NULL;
653 }
654 
655 #ifdef CONFIG_OF
656 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
657 					struct dsa_chip_data *cd,
658 					int chip_index, int port_index,
659 					struct device_node *link)
660 {
661 	const __be32 *reg;
662 	int link_sw_addr;
663 	struct device_node *parent_sw;
664 	int len;
665 
666 	parent_sw = of_get_parent(link);
667 	if (!parent_sw)
668 		return -EINVAL;
669 
670 	reg = of_get_property(parent_sw, "reg", &len);
671 	if (!reg || (len != sizeof(*reg) * 2))
672 		return -EINVAL;
673 
674 	/*
675 	 * Get the destination switch number from the second field of its 'reg'
676 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
677 	 */
678 	link_sw_addr = be32_to_cpup(reg + 1);
679 
680 	if (link_sw_addr >= pd->nr_chips)
681 		return -EINVAL;
682 
683 	cd->rtable[link_sw_addr] = port_index;
684 
685 	return 0;
686 }
687 
688 static int dsa_of_probe_links(struct dsa_platform_data *pd,
689 			      struct dsa_chip_data *cd,
690 			      int chip_index, int port_index,
691 			      struct device_node *port,
692 			      const char *port_name)
693 {
694 	struct device_node *link;
695 	int link_index;
696 	int ret;
697 
698 	for (link_index = 0;; link_index++) {
699 		link = of_parse_phandle(port, "link", link_index);
700 		if (!link)
701 			break;
702 
703 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
704 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
705 							 port_index, link);
706 			if (ret)
707 				return ret;
708 		}
709 	}
710 	return 0;
711 }
712 
713 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
714 {
715 	int i;
716 	int port_index;
717 
718 	for (i = 0; i < pd->nr_chips; i++) {
719 		port_index = 0;
720 		while (port_index < DSA_MAX_PORTS) {
721 			kfree(pd->chip[i].port_names[port_index]);
722 			port_index++;
723 		}
724 
725 		/* Drop our reference to the MDIO bus device */
726 		if (pd->chip[i].host_dev)
727 			put_device(pd->chip[i].host_dev);
728 	}
729 	kfree(pd->chip);
730 }
731 
732 static int dsa_of_probe(struct device *dev)
733 {
734 	struct device_node *np = dev->of_node;
735 	struct device_node *child, *mdio, *ethernet, *port;
736 	struct mii_bus *mdio_bus, *mdio_bus_switch;
737 	struct net_device *ethernet_dev;
738 	struct dsa_platform_data *pd;
739 	struct dsa_chip_data *cd;
740 	const char *port_name;
741 	int chip_index, port_index;
742 	const unsigned int *sw_addr, *port_reg;
743 	u32 eeprom_len;
744 	int ret;
745 
746 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
747 	if (!mdio)
748 		return -EINVAL;
749 
750 	mdio_bus = of_mdio_find_bus(mdio);
751 	if (!mdio_bus)
752 		return -EPROBE_DEFER;
753 
754 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
755 	if (!ethernet) {
756 		ret = -EINVAL;
757 		goto out_put_mdio;
758 	}
759 
760 	ethernet_dev = of_find_net_device_by_node(ethernet);
761 	if (!ethernet_dev) {
762 		ret = -EPROBE_DEFER;
763 		goto out_put_mdio;
764 	}
765 
766 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
767 	if (!pd) {
768 		ret = -ENOMEM;
769 		goto out_put_ethernet;
770 	}
771 
772 	dev->platform_data = pd;
773 	pd->of_netdev = ethernet_dev;
774 	pd->nr_chips = of_get_available_child_count(np);
775 	if (pd->nr_chips > DSA_MAX_SWITCHES)
776 		pd->nr_chips = DSA_MAX_SWITCHES;
777 
778 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
779 			   GFP_KERNEL);
780 	if (!pd->chip) {
781 		ret = -ENOMEM;
782 		goto out_free;
783 	}
784 
785 	chip_index = -1;
786 	for_each_available_child_of_node(np, child) {
787 		int i;
788 
789 		chip_index++;
790 		cd = &pd->chip[chip_index];
791 
792 		cd->of_node = child;
793 
794 		/* Initialize the routing table */
795 		for (i = 0; i < DSA_MAX_SWITCHES; ++i)
796 			cd->rtable[i] = DSA_RTABLE_NONE;
797 
798 		/* When assigning the host device, increment its refcount */
799 		cd->host_dev = get_device(&mdio_bus->dev);
800 
801 		sw_addr = of_get_property(child, "reg", NULL);
802 		if (!sw_addr)
803 			continue;
804 
805 		cd->sw_addr = be32_to_cpup(sw_addr);
806 		if (cd->sw_addr >= PHY_MAX_ADDR)
807 			continue;
808 
809 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
810 			cd->eeprom_len = eeprom_len;
811 
812 		mdio = of_parse_phandle(child, "mii-bus", 0);
813 		if (mdio) {
814 			mdio_bus_switch = of_mdio_find_bus(mdio);
815 			if (!mdio_bus_switch) {
816 				ret = -EPROBE_DEFER;
817 				goto out_free_chip;
818 			}
819 
820 			/* Drop the mdio_bus device ref, replacing the host
821 			 * device with the mdio_bus_switch device, keeping
822 			 * the refcount from of_mdio_find_bus() above.
823 			 */
824 			put_device(cd->host_dev);
825 			cd->host_dev = &mdio_bus_switch->dev;
826 		}
827 
828 		for_each_available_child_of_node(child, port) {
829 			port_reg = of_get_property(port, "reg", NULL);
830 			if (!port_reg)
831 				continue;
832 
833 			port_index = be32_to_cpup(port_reg);
834 			if (port_index >= DSA_MAX_PORTS)
835 				break;
836 
837 			port_name = of_get_property(port, "label", NULL);
838 			if (!port_name)
839 				continue;
840 
841 			cd->port_dn[port_index] = port;
842 
843 			cd->port_names[port_index] = kstrdup(port_name,
844 					GFP_KERNEL);
845 			if (!cd->port_names[port_index]) {
846 				ret = -ENOMEM;
847 				goto out_free_chip;
848 			}
849 
850 			ret = dsa_of_probe_links(pd, cd, chip_index,
851 						 port_index, port, port_name);
852 			if (ret)
853 				goto out_free_chip;
854 
855 		}
856 	}
857 
858 	/* The individual chips hold their own refcount on the mdio bus,
859 	 * so drop ours */
860 	put_device(&mdio_bus->dev);
861 
862 	return 0;
863 
864 out_free_chip:
865 	dsa_of_free_platform_data(pd);
866 out_free:
867 	kfree(pd);
868 	dev->platform_data = NULL;
869 out_put_ethernet:
870 	put_device(&ethernet_dev->dev);
871 out_put_mdio:
872 	put_device(&mdio_bus->dev);
873 	return ret;
874 }
875 
876 static void dsa_of_remove(struct device *dev)
877 {
878 	struct dsa_platform_data *pd = dev->platform_data;
879 
880 	if (!dev->of_node)
881 		return;
882 
883 	dsa_of_free_platform_data(pd);
884 	put_device(&pd->of_netdev->dev);
885 	kfree(pd);
886 }
887 #else
888 static inline int dsa_of_probe(struct device *dev)
889 {
890 	return 0;
891 }
892 
893 static inline void dsa_of_remove(struct device *dev)
894 {
895 }
896 #endif
897 
898 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
899 			 struct device *parent, struct dsa_platform_data *pd)
900 {
901 	int i;
902 	unsigned configured = 0;
903 
904 	dst->pd = pd;
905 	dst->master_netdev = dev;
906 	dst->cpu_switch = -1;
907 	dst->cpu_port = -1;
908 
909 	for (i = 0; i < pd->nr_chips; i++) {
910 		struct dsa_switch *ds;
911 
912 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
913 		if (IS_ERR(ds)) {
914 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
915 				   i, PTR_ERR(ds));
916 			continue;
917 		}
918 
919 		dst->ds[i] = ds;
920 
921 		++configured;
922 	}
923 
924 	/*
925 	 * If no switch was found, exit cleanly
926 	 */
927 	if (!configured)
928 		return -EPROBE_DEFER;
929 
930 	/*
931 	 * If we use a tagging format that doesn't have an ethertype
932 	 * field, make sure that all packets from this point on get
933 	 * sent to the tag format's receive function.
934 	 */
935 	wmb();
936 	dev->dsa_ptr = (void *)dst;
937 
938 	return 0;
939 }
940 
941 static int dsa_probe(struct platform_device *pdev)
942 {
943 	struct dsa_platform_data *pd = pdev->dev.platform_data;
944 	struct net_device *dev;
945 	struct dsa_switch_tree *dst;
946 	int ret;
947 
948 	pr_notice_once("Distributed Switch Architecture driver version %s\n",
949 		       dsa_driver_version);
950 
951 	if (pdev->dev.of_node) {
952 		ret = dsa_of_probe(&pdev->dev);
953 		if (ret)
954 			return ret;
955 
956 		pd = pdev->dev.platform_data;
957 	}
958 
959 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
960 		return -EINVAL;
961 
962 	if (pd->of_netdev) {
963 		dev = pd->of_netdev;
964 		dev_hold(dev);
965 	} else {
966 		dev = dev_to_net_device(pd->netdev);
967 	}
968 	if (dev == NULL) {
969 		ret = -EPROBE_DEFER;
970 		goto out;
971 	}
972 
973 	if (dev->dsa_ptr != NULL) {
974 		dev_put(dev);
975 		ret = -EEXIST;
976 		goto out;
977 	}
978 
979 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
980 	if (dst == NULL) {
981 		dev_put(dev);
982 		ret = -ENOMEM;
983 		goto out;
984 	}
985 
986 	platform_set_drvdata(pdev, dst);
987 
988 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
989 	if (ret) {
990 		dev_put(dev);
991 		goto out;
992 	}
993 
994 	return 0;
995 
996 out:
997 	dsa_of_remove(&pdev->dev);
998 
999 	return ret;
1000 }
1001 
1002 static void dsa_remove_dst(struct dsa_switch_tree *dst)
1003 {
1004 	int i;
1005 
1006 	dst->master_netdev->dsa_ptr = NULL;
1007 
1008 	/* If we used a tagging format that doesn't have an ethertype
1009 	 * field, make sure that all packets from this point get sent
1010 	 * without the tag and go through the regular receive path.
1011 	 */
1012 	wmb();
1013 
1014 	for (i = 0; i < dst->pd->nr_chips; i++) {
1015 		struct dsa_switch *ds = dst->ds[i];
1016 
1017 		if (ds)
1018 			dsa_switch_destroy(ds);
1019 	}
1020 
1021 	dsa_cpu_port_ethtool_restore(dst->ds[0]);
1022 
1023 	dev_put(dst->master_netdev);
1024 }
1025 
1026 static int dsa_remove(struct platform_device *pdev)
1027 {
1028 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1029 
1030 	dsa_remove_dst(dst);
1031 	dsa_of_remove(&pdev->dev);
1032 
1033 	return 0;
1034 }
1035 
1036 static void dsa_shutdown(struct platform_device *pdev)
1037 {
1038 }
1039 
1040 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
1041 			  struct packet_type *pt, struct net_device *orig_dev)
1042 {
1043 	struct dsa_switch_tree *dst = dev->dsa_ptr;
1044 
1045 	if (unlikely(dst == NULL)) {
1046 		kfree_skb(skb);
1047 		return 0;
1048 	}
1049 
1050 	return dst->rcv(skb, dev, pt, orig_dev);
1051 }
1052 
1053 static struct packet_type dsa_pack_type __read_mostly = {
1054 	.type	= cpu_to_be16(ETH_P_XDSA),
1055 	.func	= dsa_switch_rcv,
1056 };
1057 
1058 static struct notifier_block dsa_netdevice_nb __read_mostly = {
1059 	.notifier_call	= dsa_slave_netdevice_event,
1060 };
1061 
1062 #ifdef CONFIG_PM_SLEEP
1063 static int dsa_suspend(struct device *d)
1064 {
1065 	struct platform_device *pdev = to_platform_device(d);
1066 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1067 	int i, ret = 0;
1068 
1069 	for (i = 0; i < dst->pd->nr_chips; i++) {
1070 		struct dsa_switch *ds = dst->ds[i];
1071 
1072 		if (ds != NULL)
1073 			ret = dsa_switch_suspend(ds);
1074 	}
1075 
1076 	return ret;
1077 }
1078 
1079 static int dsa_resume(struct device *d)
1080 {
1081 	struct platform_device *pdev = to_platform_device(d);
1082 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1083 	int i, ret = 0;
1084 
1085 	for (i = 0; i < dst->pd->nr_chips; i++) {
1086 		struct dsa_switch *ds = dst->ds[i];
1087 
1088 		if (ds != NULL)
1089 			ret = dsa_switch_resume(ds);
1090 	}
1091 
1092 	return ret;
1093 }
1094 #endif
1095 
1096 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
1097 
1098 static const struct of_device_id dsa_of_match_table[] = {
1099 	{ .compatible = "marvell,dsa", },
1100 	{}
1101 };
1102 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
1103 
1104 static struct platform_driver dsa_driver = {
1105 	.probe		= dsa_probe,
1106 	.remove		= dsa_remove,
1107 	.shutdown	= dsa_shutdown,
1108 	.driver = {
1109 		.name	= "dsa",
1110 		.of_match_table = dsa_of_match_table,
1111 		.pm	= &dsa_pm_ops,
1112 	},
1113 };
1114 
1115 static int __init dsa_init_module(void)
1116 {
1117 	int rc;
1118 
1119 	register_netdevice_notifier(&dsa_netdevice_nb);
1120 
1121 	rc = platform_driver_register(&dsa_driver);
1122 	if (rc)
1123 		return rc;
1124 
1125 	dev_add_pack(&dsa_pack_type);
1126 
1127 	return 0;
1128 }
1129 module_init(dsa_init_module);
1130 
1131 static void __exit dsa_cleanup_module(void)
1132 {
1133 	unregister_netdevice_notifier(&dsa_netdevice_nb);
1134 	dev_remove_pack(&dsa_pack_type);
1135 	platform_driver_unregister(&dsa_driver);
1136 }
1137 module_exit(dsa_cleanup_module);
1138 
1139 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
1140 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
1141 MODULE_LICENSE("GPL");
1142 MODULE_ALIAS("platform:dsa");
1143