xref: /openbmc/linux/net/dsa/dsa.c (revision 2572f00d)
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/sysfs.h>
25 #include <linux/phy_fixed.h>
26 #include "dsa_priv.h"
27 
28 char dsa_driver_version[] = "0.1";
29 
30 
31 /* switch driver registration ***********************************************/
32 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
33 static LIST_HEAD(dsa_switch_drivers);
34 
35 void register_switch_driver(struct dsa_switch_driver *drv)
36 {
37 	mutex_lock(&dsa_switch_drivers_mutex);
38 	list_add_tail(&drv->list, &dsa_switch_drivers);
39 	mutex_unlock(&dsa_switch_drivers_mutex);
40 }
41 EXPORT_SYMBOL_GPL(register_switch_driver);
42 
43 void unregister_switch_driver(struct dsa_switch_driver *drv)
44 {
45 	mutex_lock(&dsa_switch_drivers_mutex);
46 	list_del_init(&drv->list);
47 	mutex_unlock(&dsa_switch_drivers_mutex);
48 }
49 EXPORT_SYMBOL_GPL(unregister_switch_driver);
50 
51 static struct dsa_switch_driver *
52 dsa_switch_probe(struct device *host_dev, int sw_addr, char **_name)
53 {
54 	struct dsa_switch_driver *ret;
55 	struct list_head *list;
56 	char *name;
57 
58 	ret = NULL;
59 	name = NULL;
60 
61 	mutex_lock(&dsa_switch_drivers_mutex);
62 	list_for_each(list, &dsa_switch_drivers) {
63 		struct dsa_switch_driver *drv;
64 
65 		drv = list_entry(list, struct dsa_switch_driver, list);
66 
67 		name = drv->probe(host_dev, sw_addr);
68 		if (name != NULL) {
69 			ret = drv;
70 			break;
71 		}
72 	}
73 	mutex_unlock(&dsa_switch_drivers_mutex);
74 
75 	*_name = name;
76 
77 	return ret;
78 }
79 
80 /* hwmon support ************************************************************/
81 
82 #ifdef CONFIG_NET_DSA_HWMON
83 
84 static ssize_t temp1_input_show(struct device *dev,
85 				struct device_attribute *attr, char *buf)
86 {
87 	struct dsa_switch *ds = dev_get_drvdata(dev);
88 	int temp, ret;
89 
90 	ret = ds->drv->get_temp(ds, &temp);
91 	if (ret < 0)
92 		return ret;
93 
94 	return sprintf(buf, "%d\n", temp * 1000);
95 }
96 static DEVICE_ATTR_RO(temp1_input);
97 
98 static ssize_t temp1_max_show(struct device *dev,
99 			      struct device_attribute *attr, char *buf)
100 {
101 	struct dsa_switch *ds = dev_get_drvdata(dev);
102 	int temp, ret;
103 
104 	ret = ds->drv->get_temp_limit(ds, &temp);
105 	if (ret < 0)
106 		return ret;
107 
108 	return sprintf(buf, "%d\n", temp * 1000);
109 }
110 
111 static ssize_t temp1_max_store(struct device *dev,
112 			       struct device_attribute *attr, const char *buf,
113 			       size_t count)
114 {
115 	struct dsa_switch *ds = dev_get_drvdata(dev);
116 	int temp, ret;
117 
118 	ret = kstrtoint(buf, 0, &temp);
119 	if (ret < 0)
120 		return ret;
121 
122 	ret = ds->drv->set_temp_limit(ds, DIV_ROUND_CLOSEST(temp, 1000));
123 	if (ret < 0)
124 		return ret;
125 
126 	return count;
127 }
128 static DEVICE_ATTR_RW(temp1_max);
129 
130 static ssize_t temp1_max_alarm_show(struct device *dev,
131 				    struct device_attribute *attr, char *buf)
132 {
133 	struct dsa_switch *ds = dev_get_drvdata(dev);
134 	bool alarm;
135 	int ret;
136 
137 	ret = ds->drv->get_temp_alarm(ds, &alarm);
138 	if (ret < 0)
139 		return ret;
140 
141 	return sprintf(buf, "%d\n", alarm);
142 }
143 static DEVICE_ATTR_RO(temp1_max_alarm);
144 
145 static struct attribute *dsa_hwmon_attrs[] = {
146 	&dev_attr_temp1_input.attr,	/* 0 */
147 	&dev_attr_temp1_max.attr,	/* 1 */
148 	&dev_attr_temp1_max_alarm.attr,	/* 2 */
149 	NULL
150 };
151 
152 static umode_t dsa_hwmon_attrs_visible(struct kobject *kobj,
153 				       struct attribute *attr, int index)
154 {
155 	struct device *dev = container_of(kobj, struct device, kobj);
156 	struct dsa_switch *ds = dev_get_drvdata(dev);
157 	struct dsa_switch_driver *drv = ds->drv;
158 	umode_t mode = attr->mode;
159 
160 	if (index == 1) {
161 		if (!drv->get_temp_limit)
162 			mode = 0;
163 		else if (!drv->set_temp_limit)
164 			mode &= ~S_IWUSR;
165 	} else if (index == 2 && !drv->get_temp_alarm) {
166 		mode = 0;
167 	}
168 	return mode;
169 }
170 
171 static const struct attribute_group dsa_hwmon_group = {
172 	.attrs = dsa_hwmon_attrs,
173 	.is_visible = dsa_hwmon_attrs_visible,
174 };
175 __ATTRIBUTE_GROUPS(dsa_hwmon);
176 
177 #endif /* CONFIG_NET_DSA_HWMON */
178 
179 /* basic switch operations **************************************************/
180 static int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct net_device *master)
181 {
182 	struct dsa_chip_data *cd = ds->pd;
183 	struct device_node *port_dn;
184 	struct phy_device *phydev;
185 	int ret, port, mode;
186 
187 	for (port = 0; port < DSA_MAX_PORTS; port++) {
188 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
189 			continue;
190 
191 		port_dn = cd->port_dn[port];
192 		if (of_phy_is_fixed_link(port_dn)) {
193 			ret = of_phy_register_fixed_link(port_dn);
194 			if (ret) {
195 				netdev_err(master,
196 					   "failed to register fixed PHY\n");
197 				return ret;
198 			}
199 			phydev = of_phy_find_device(port_dn);
200 
201 			mode = of_get_phy_mode(port_dn);
202 			if (mode < 0)
203 				mode = PHY_INTERFACE_MODE_NA;
204 			phydev->interface = mode;
205 
206 			genphy_config_init(phydev);
207 			genphy_read_status(phydev);
208 			if (ds->drv->adjust_link)
209 				ds->drv->adjust_link(ds, port, phydev);
210 		}
211 	}
212 	return 0;
213 }
214 
215 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
216 {
217 	struct dsa_switch_driver *drv = ds->drv;
218 	struct dsa_switch_tree *dst = ds->dst;
219 	struct dsa_chip_data *pd = ds->pd;
220 	bool valid_name_found = false;
221 	int index = ds->index;
222 	int i, ret;
223 
224 	/*
225 	 * Validate supplied switch configuration.
226 	 */
227 	for (i = 0; i < DSA_MAX_PORTS; i++) {
228 		char *name;
229 
230 		name = pd->port_names[i];
231 		if (name == NULL)
232 			continue;
233 
234 		if (!strcmp(name, "cpu")) {
235 			if (dst->cpu_switch != -1) {
236 				netdev_err(dst->master_netdev,
237 					   "multiple cpu ports?!\n");
238 				ret = -EINVAL;
239 				goto out;
240 			}
241 			dst->cpu_switch = index;
242 			dst->cpu_port = i;
243 		} else if (!strcmp(name, "dsa")) {
244 			ds->dsa_port_mask |= 1 << i;
245 		} else {
246 			ds->phys_port_mask |= 1 << i;
247 		}
248 		valid_name_found = true;
249 	}
250 
251 	if (!valid_name_found && i == DSA_MAX_PORTS) {
252 		ret = -EINVAL;
253 		goto out;
254 	}
255 
256 	/* Make the built-in MII bus mask match the number of ports,
257 	 * switch drivers can override this later
258 	 */
259 	ds->phys_mii_mask = ds->phys_port_mask;
260 
261 	/*
262 	 * If the CPU connects to this switch, set the switch tree
263 	 * tagging protocol to the preferred tagging format of this
264 	 * switch.
265 	 */
266 	if (dst->cpu_switch == index) {
267 		switch (ds->tag_protocol) {
268 #ifdef CONFIG_NET_DSA_TAG_DSA
269 		case DSA_TAG_PROTO_DSA:
270 			dst->rcv = dsa_netdev_ops.rcv;
271 			break;
272 #endif
273 #ifdef CONFIG_NET_DSA_TAG_EDSA
274 		case DSA_TAG_PROTO_EDSA:
275 			dst->rcv = edsa_netdev_ops.rcv;
276 			break;
277 #endif
278 #ifdef CONFIG_NET_DSA_TAG_TRAILER
279 		case DSA_TAG_PROTO_TRAILER:
280 			dst->rcv = trailer_netdev_ops.rcv;
281 			break;
282 #endif
283 #ifdef CONFIG_NET_DSA_TAG_BRCM
284 		case DSA_TAG_PROTO_BRCM:
285 			dst->rcv = brcm_netdev_ops.rcv;
286 			break;
287 #endif
288 		case DSA_TAG_PROTO_NONE:
289 			break;
290 		default:
291 			ret = -ENOPROTOOPT;
292 			goto out;
293 		}
294 
295 		dst->tag_protocol = ds->tag_protocol;
296 	}
297 
298 	/*
299 	 * Do basic register setup.
300 	 */
301 	ret = drv->setup(ds);
302 	if (ret < 0)
303 		goto out;
304 
305 	ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
306 	if (ret < 0)
307 		goto out;
308 
309 	ds->slave_mii_bus = devm_mdiobus_alloc(parent);
310 	if (ds->slave_mii_bus == NULL) {
311 		ret = -ENOMEM;
312 		goto out;
313 	}
314 	dsa_slave_mii_bus_init(ds);
315 
316 	ret = mdiobus_register(ds->slave_mii_bus);
317 	if (ret < 0)
318 		goto out;
319 
320 
321 	/*
322 	 * Create network devices for physical switch ports.
323 	 */
324 	for (i = 0; i < DSA_MAX_PORTS; i++) {
325 		if (!(ds->phys_port_mask & (1 << i)))
326 			continue;
327 
328 		ret = dsa_slave_create(ds, parent, i, pd->port_names[i]);
329 		if (ret < 0) {
330 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
331 				   index, i, pd->port_names[i], ret);
332 			ret = 0;
333 		}
334 	}
335 
336 	/* Perform configuration of the CPU and DSA ports */
337 	ret = dsa_cpu_dsa_setup(ds, dst->master_netdev);
338 	if (ret < 0) {
339 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
340 			   index);
341 		ret = 0;
342 	}
343 
344 #ifdef CONFIG_NET_DSA_HWMON
345 	/* If the switch provides a temperature sensor,
346 	 * register with hardware monitoring subsystem.
347 	 * Treat registration error as non-fatal and ignore it.
348 	 */
349 	if (drv->get_temp) {
350 		const char *netname = netdev_name(dst->master_netdev);
351 		char hname[IFNAMSIZ + 1];
352 		int i, j;
353 
354 		/* Create valid hwmon 'name' attribute */
355 		for (i = j = 0; i < IFNAMSIZ && netname[i]; i++) {
356 			if (isalnum(netname[i]))
357 				hname[j++] = netname[i];
358 		}
359 		hname[j] = '\0';
360 		scnprintf(ds->hwmon_name, sizeof(ds->hwmon_name), "%s_dsa%d",
361 			  hname, index);
362 		ds->hwmon_dev = hwmon_device_register_with_groups(NULL,
363 					ds->hwmon_name, ds, dsa_hwmon_groups);
364 		if (IS_ERR(ds->hwmon_dev))
365 			ds->hwmon_dev = NULL;
366 	}
367 #endif /* CONFIG_NET_DSA_HWMON */
368 
369 	return ret;
370 
371 out:
372 	return ret;
373 }
374 
375 static struct dsa_switch *
376 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
377 		 struct device *parent, struct device *host_dev)
378 {
379 	struct dsa_chip_data *pd = dst->pd->chip + index;
380 	struct dsa_switch_driver *drv;
381 	struct dsa_switch *ds;
382 	int ret;
383 	char *name;
384 
385 	/*
386 	 * Probe for switch model.
387 	 */
388 	drv = dsa_switch_probe(host_dev, pd->sw_addr, &name);
389 	if (drv == NULL) {
390 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
391 			   index);
392 		return ERR_PTR(-EINVAL);
393 	}
394 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
395 		    index, name);
396 
397 
398 	/*
399 	 * Allocate and initialise switch state.
400 	 */
401 	ds = devm_kzalloc(parent, sizeof(*ds) + drv->priv_size, GFP_KERNEL);
402 	if (ds == NULL)
403 		return ERR_PTR(-ENOMEM);
404 
405 	ds->dst = dst;
406 	ds->index = index;
407 	ds->pd = pd;
408 	ds->drv = drv;
409 	ds->tag_protocol = drv->tag_protocol;
410 	ds->master_dev = host_dev;
411 
412 	ret = dsa_switch_setup_one(ds, parent);
413 	if (ret)
414 		return ERR_PTR(ret);
415 
416 	return ds;
417 }
418 
419 static void dsa_switch_destroy(struct dsa_switch *ds)
420 {
421 	struct device_node *port_dn;
422 	struct phy_device *phydev;
423 	struct dsa_chip_data *cd = ds->pd;
424 	int port;
425 
426 #ifdef CONFIG_NET_DSA_HWMON
427 	if (ds->hwmon_dev)
428 		hwmon_device_unregister(ds->hwmon_dev);
429 #endif
430 
431 	/* Disable configuration of the CPU and DSA ports */
432 	for (port = 0; port < DSA_MAX_PORTS; port++) {
433 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
434 			continue;
435 
436 		port_dn = cd->port_dn[port];
437 		if (of_phy_is_fixed_link(port_dn)) {
438 			phydev = of_phy_find_device(port_dn);
439 			if (phydev) {
440 				int addr = phydev->addr;
441 
442 				phy_device_free(phydev);
443 				of_node_put(port_dn);
444 				fixed_phy_del(addr);
445 			}
446 		}
447 	}
448 
449 	/* Destroy network devices for physical switch ports. */
450 	for (port = 0; port < DSA_MAX_PORTS; port++) {
451 		if (!(ds->phys_port_mask & (1 << port)))
452 			continue;
453 
454 		if (!ds->ports[port])
455 			continue;
456 
457 		unregister_netdev(ds->ports[port]);
458 		free_netdev(ds->ports[port]);
459 	}
460 
461 	mdiobus_unregister(ds->slave_mii_bus);
462 }
463 
464 #ifdef CONFIG_PM_SLEEP
465 static int dsa_switch_suspend(struct dsa_switch *ds)
466 {
467 	int i, ret = 0;
468 
469 	/* Suspend slave network devices */
470 	for (i = 0; i < DSA_MAX_PORTS; i++) {
471 		if (!dsa_is_port_initialized(ds, i))
472 			continue;
473 
474 		ret = dsa_slave_suspend(ds->ports[i]);
475 		if (ret)
476 			return ret;
477 	}
478 
479 	if (ds->drv->suspend)
480 		ret = ds->drv->suspend(ds);
481 
482 	return ret;
483 }
484 
485 static int dsa_switch_resume(struct dsa_switch *ds)
486 {
487 	int i, ret = 0;
488 
489 	if (ds->drv->resume)
490 		ret = ds->drv->resume(ds);
491 
492 	if (ret)
493 		return ret;
494 
495 	/* Resume slave network devices */
496 	for (i = 0; i < DSA_MAX_PORTS; i++) {
497 		if (!dsa_is_port_initialized(ds, i))
498 			continue;
499 
500 		ret = dsa_slave_resume(ds->ports[i]);
501 		if (ret)
502 			return ret;
503 	}
504 
505 	return 0;
506 }
507 #endif
508 
509 
510 /* link polling *************************************************************/
511 static void dsa_link_poll_work(struct work_struct *ugly)
512 {
513 	struct dsa_switch_tree *dst;
514 	int i;
515 
516 	dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
517 
518 	for (i = 0; i < dst->pd->nr_chips; i++) {
519 		struct dsa_switch *ds = dst->ds[i];
520 
521 		if (ds != NULL && ds->drv->poll_link != NULL)
522 			ds->drv->poll_link(ds);
523 	}
524 
525 	mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
526 }
527 
528 static void dsa_link_poll_timer(unsigned long _dst)
529 {
530 	struct dsa_switch_tree *dst = (void *)_dst;
531 
532 	schedule_work(&dst->link_poll_work);
533 }
534 
535 
536 /* platform driver init and cleanup *****************************************/
537 static int dev_is_class(struct device *dev, void *class)
538 {
539 	if (dev->class != NULL && !strcmp(dev->class->name, class))
540 		return 1;
541 
542 	return 0;
543 }
544 
545 static struct device *dev_find_class(struct device *parent, char *class)
546 {
547 	if (dev_is_class(parent, class)) {
548 		get_device(parent);
549 		return parent;
550 	}
551 
552 	return device_find_child(parent, class, dev_is_class);
553 }
554 
555 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
556 {
557 	struct device *d;
558 
559 	d = dev_find_class(dev, "mdio_bus");
560 	if (d != NULL) {
561 		struct mii_bus *bus;
562 
563 		bus = to_mii_bus(d);
564 		put_device(d);
565 
566 		return bus;
567 	}
568 
569 	return NULL;
570 }
571 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
572 
573 static struct net_device *dev_to_net_device(struct device *dev)
574 {
575 	struct device *d;
576 
577 	d = dev_find_class(dev, "net");
578 	if (d != NULL) {
579 		struct net_device *nd;
580 
581 		nd = to_net_dev(d);
582 		dev_hold(nd);
583 		put_device(d);
584 
585 		return nd;
586 	}
587 
588 	return NULL;
589 }
590 
591 #ifdef CONFIG_OF
592 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
593 					struct dsa_chip_data *cd,
594 					int chip_index, int port_index,
595 					struct device_node *link)
596 {
597 	const __be32 *reg;
598 	int link_sw_addr;
599 	struct device_node *parent_sw;
600 	int len;
601 
602 	parent_sw = of_get_parent(link);
603 	if (!parent_sw)
604 		return -EINVAL;
605 
606 	reg = of_get_property(parent_sw, "reg", &len);
607 	if (!reg || (len != sizeof(*reg) * 2))
608 		return -EINVAL;
609 
610 	/*
611 	 * Get the destination switch number from the second field of its 'reg'
612 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
613 	 */
614 	link_sw_addr = be32_to_cpup(reg + 1);
615 
616 	if (link_sw_addr >= pd->nr_chips)
617 		return -EINVAL;
618 
619 	/* First time routing table allocation */
620 	if (!cd->rtable) {
621 		cd->rtable = kmalloc_array(pd->nr_chips, sizeof(s8),
622 					   GFP_KERNEL);
623 		if (!cd->rtable)
624 			return -ENOMEM;
625 
626 		/* default to no valid uplink/downlink */
627 		memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
628 	}
629 
630 	cd->rtable[link_sw_addr] = port_index;
631 
632 	return 0;
633 }
634 
635 static int dsa_of_probe_links(struct dsa_platform_data *pd,
636 			      struct dsa_chip_data *cd,
637 			      int chip_index, int port_index,
638 			      struct device_node *port,
639 			      const char *port_name)
640 {
641 	struct device_node *link;
642 	int link_index;
643 	int ret;
644 
645 	for (link_index = 0;; link_index++) {
646 		link = of_parse_phandle(port, "link", link_index);
647 		if (!link)
648 			break;
649 
650 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
651 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
652 							 port_index, link);
653 			if (ret)
654 				return ret;
655 		}
656 	}
657 	return 0;
658 }
659 
660 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
661 {
662 	int i;
663 	int port_index;
664 
665 	for (i = 0; i < pd->nr_chips; i++) {
666 		port_index = 0;
667 		while (port_index < DSA_MAX_PORTS) {
668 			kfree(pd->chip[i].port_names[port_index]);
669 			port_index++;
670 		}
671 		kfree(pd->chip[i].rtable);
672 
673 		/* Drop our reference to the MDIO bus device */
674 		if (pd->chip[i].host_dev)
675 			put_device(pd->chip[i].host_dev);
676 	}
677 	kfree(pd->chip);
678 }
679 
680 static int dsa_of_probe(struct device *dev)
681 {
682 	struct device_node *np = dev->of_node;
683 	struct device_node *child, *mdio, *ethernet, *port;
684 	struct mii_bus *mdio_bus, *mdio_bus_switch;
685 	struct net_device *ethernet_dev;
686 	struct dsa_platform_data *pd;
687 	struct dsa_chip_data *cd;
688 	const char *port_name;
689 	int chip_index, port_index;
690 	const unsigned int *sw_addr, *port_reg;
691 	u32 eeprom_len;
692 	int ret;
693 
694 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
695 	if (!mdio)
696 		return -EINVAL;
697 
698 	mdio_bus = of_mdio_find_bus(mdio);
699 	if (!mdio_bus)
700 		return -EPROBE_DEFER;
701 
702 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
703 	if (!ethernet) {
704 		ret = -EINVAL;
705 		goto out_put_mdio;
706 	}
707 
708 	ethernet_dev = of_find_net_device_by_node(ethernet);
709 	if (!ethernet_dev) {
710 		ret = -EPROBE_DEFER;
711 		goto out_put_mdio;
712 	}
713 
714 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
715 	if (!pd) {
716 		ret = -ENOMEM;
717 		goto out_put_ethernet;
718 	}
719 
720 	dev->platform_data = pd;
721 	pd->of_netdev = ethernet_dev;
722 	pd->nr_chips = of_get_available_child_count(np);
723 	if (pd->nr_chips > DSA_MAX_SWITCHES)
724 		pd->nr_chips = DSA_MAX_SWITCHES;
725 
726 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
727 			   GFP_KERNEL);
728 	if (!pd->chip) {
729 		ret = -ENOMEM;
730 		goto out_free;
731 	}
732 
733 	chip_index = -1;
734 	for_each_available_child_of_node(np, child) {
735 		chip_index++;
736 		cd = &pd->chip[chip_index];
737 
738 		cd->of_node = child;
739 
740 		/* When assigning the host device, increment its refcount */
741 		cd->host_dev = get_device(&mdio_bus->dev);
742 
743 		sw_addr = of_get_property(child, "reg", NULL);
744 		if (!sw_addr)
745 			continue;
746 
747 		cd->sw_addr = be32_to_cpup(sw_addr);
748 		if (cd->sw_addr >= PHY_MAX_ADDR)
749 			continue;
750 
751 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
752 			cd->eeprom_len = eeprom_len;
753 
754 		mdio = of_parse_phandle(child, "mii-bus", 0);
755 		if (mdio) {
756 			mdio_bus_switch = of_mdio_find_bus(mdio);
757 			if (!mdio_bus_switch) {
758 				ret = -EPROBE_DEFER;
759 				goto out_free_chip;
760 			}
761 
762 			/* Drop the mdio_bus device ref, replacing the host
763 			 * device with the mdio_bus_switch device, keeping
764 			 * the refcount from of_mdio_find_bus() above.
765 			 */
766 			put_device(cd->host_dev);
767 			cd->host_dev = &mdio_bus_switch->dev;
768 		}
769 
770 		for_each_available_child_of_node(child, port) {
771 			port_reg = of_get_property(port, "reg", NULL);
772 			if (!port_reg)
773 				continue;
774 
775 			port_index = be32_to_cpup(port_reg);
776 			if (port_index >= DSA_MAX_PORTS)
777 				break;
778 
779 			port_name = of_get_property(port, "label", NULL);
780 			if (!port_name)
781 				continue;
782 
783 			cd->port_dn[port_index] = port;
784 
785 			cd->port_names[port_index] = kstrdup(port_name,
786 					GFP_KERNEL);
787 			if (!cd->port_names[port_index]) {
788 				ret = -ENOMEM;
789 				goto out_free_chip;
790 			}
791 
792 			ret = dsa_of_probe_links(pd, cd, chip_index,
793 						 port_index, port, port_name);
794 			if (ret)
795 				goto out_free_chip;
796 
797 		}
798 	}
799 
800 	/* The individual chips hold their own refcount on the mdio bus,
801 	 * so drop ours */
802 	put_device(&mdio_bus->dev);
803 
804 	return 0;
805 
806 out_free_chip:
807 	dsa_of_free_platform_data(pd);
808 out_free:
809 	kfree(pd);
810 	dev->platform_data = NULL;
811 out_put_ethernet:
812 	put_device(&ethernet_dev->dev);
813 out_put_mdio:
814 	put_device(&mdio_bus->dev);
815 	return ret;
816 }
817 
818 static void dsa_of_remove(struct device *dev)
819 {
820 	struct dsa_platform_data *pd = dev->platform_data;
821 
822 	if (!dev->of_node)
823 		return;
824 
825 	dsa_of_free_platform_data(pd);
826 	put_device(&pd->of_netdev->dev);
827 	kfree(pd);
828 }
829 #else
830 static inline int dsa_of_probe(struct device *dev)
831 {
832 	return 0;
833 }
834 
835 static inline void dsa_of_remove(struct device *dev)
836 {
837 }
838 #endif
839 
840 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
841 			 struct device *parent, struct dsa_platform_data *pd)
842 {
843 	int i;
844 	unsigned configured = 0;
845 
846 	dst->pd = pd;
847 	dst->master_netdev = dev;
848 	dst->cpu_switch = -1;
849 	dst->cpu_port = -1;
850 
851 	for (i = 0; i < pd->nr_chips; i++) {
852 		struct dsa_switch *ds;
853 
854 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
855 		if (IS_ERR(ds)) {
856 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
857 				   i, PTR_ERR(ds));
858 			continue;
859 		}
860 
861 		dst->ds[i] = ds;
862 		if (ds->drv->poll_link != NULL)
863 			dst->link_poll_needed = 1;
864 
865 		++configured;
866 	}
867 
868 	/*
869 	 * If no switch was found, exit cleanly
870 	 */
871 	if (!configured)
872 		return -EPROBE_DEFER;
873 
874 	/*
875 	 * If we use a tagging format that doesn't have an ethertype
876 	 * field, make sure that all packets from this point on get
877 	 * sent to the tag format's receive function.
878 	 */
879 	wmb();
880 	dev->dsa_ptr = (void *)dst;
881 
882 	if (dst->link_poll_needed) {
883 		INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
884 		init_timer(&dst->link_poll_timer);
885 		dst->link_poll_timer.data = (unsigned long)dst;
886 		dst->link_poll_timer.function = dsa_link_poll_timer;
887 		dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
888 		add_timer(&dst->link_poll_timer);
889 	}
890 
891 	return 0;
892 }
893 
894 static int dsa_probe(struct platform_device *pdev)
895 {
896 	struct dsa_platform_data *pd = pdev->dev.platform_data;
897 	struct net_device *dev;
898 	struct dsa_switch_tree *dst;
899 	int ret;
900 
901 	pr_notice_once("Distributed Switch Architecture driver version %s\n",
902 		       dsa_driver_version);
903 
904 	if (pdev->dev.of_node) {
905 		ret = dsa_of_probe(&pdev->dev);
906 		if (ret)
907 			return ret;
908 
909 		pd = pdev->dev.platform_data;
910 	}
911 
912 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
913 		return -EINVAL;
914 
915 	if (pd->of_netdev) {
916 		dev = pd->of_netdev;
917 		dev_hold(dev);
918 	} else {
919 		dev = dev_to_net_device(pd->netdev);
920 	}
921 	if (dev == NULL) {
922 		ret = -EPROBE_DEFER;
923 		goto out;
924 	}
925 
926 	if (dev->dsa_ptr != NULL) {
927 		dev_put(dev);
928 		ret = -EEXIST;
929 		goto out;
930 	}
931 
932 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
933 	if (dst == NULL) {
934 		dev_put(dev);
935 		ret = -ENOMEM;
936 		goto out;
937 	}
938 
939 	platform_set_drvdata(pdev, dst);
940 
941 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
942 	if (ret)
943 		goto out;
944 
945 	return 0;
946 
947 out:
948 	dsa_of_remove(&pdev->dev);
949 
950 	return ret;
951 }
952 
953 static void dsa_remove_dst(struct dsa_switch_tree *dst)
954 {
955 	int i;
956 
957 	if (dst->link_poll_needed)
958 		del_timer_sync(&dst->link_poll_timer);
959 
960 	flush_work(&dst->link_poll_work);
961 
962 	for (i = 0; i < dst->pd->nr_chips; i++) {
963 		struct dsa_switch *ds = dst->ds[i];
964 
965 		if (ds)
966 			dsa_switch_destroy(ds);
967 	}
968 }
969 
970 static int dsa_remove(struct platform_device *pdev)
971 {
972 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
973 
974 	dsa_remove_dst(dst);
975 	dsa_of_remove(&pdev->dev);
976 
977 	return 0;
978 }
979 
980 static void dsa_shutdown(struct platform_device *pdev)
981 {
982 }
983 
984 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
985 			  struct packet_type *pt, struct net_device *orig_dev)
986 {
987 	struct dsa_switch_tree *dst = dev->dsa_ptr;
988 
989 	if (unlikely(dst == NULL)) {
990 		kfree_skb(skb);
991 		return 0;
992 	}
993 
994 	return dst->rcv(skb, dev, pt, orig_dev);
995 }
996 
997 static struct packet_type dsa_pack_type __read_mostly = {
998 	.type	= cpu_to_be16(ETH_P_XDSA),
999 	.func	= dsa_switch_rcv,
1000 };
1001 
1002 static struct notifier_block dsa_netdevice_nb __read_mostly = {
1003 	.notifier_call	= dsa_slave_netdevice_event,
1004 };
1005 
1006 #ifdef CONFIG_PM_SLEEP
1007 static int dsa_suspend(struct device *d)
1008 {
1009 	struct platform_device *pdev = to_platform_device(d);
1010 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1011 	int i, ret = 0;
1012 
1013 	for (i = 0; i < dst->pd->nr_chips; i++) {
1014 		struct dsa_switch *ds = dst->ds[i];
1015 
1016 		if (ds != NULL)
1017 			ret = dsa_switch_suspend(ds);
1018 	}
1019 
1020 	return ret;
1021 }
1022 
1023 static int dsa_resume(struct device *d)
1024 {
1025 	struct platform_device *pdev = to_platform_device(d);
1026 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1027 	int i, ret = 0;
1028 
1029 	for (i = 0; i < dst->pd->nr_chips; i++) {
1030 		struct dsa_switch *ds = dst->ds[i];
1031 
1032 		if (ds != NULL)
1033 			ret = dsa_switch_resume(ds);
1034 	}
1035 
1036 	return ret;
1037 }
1038 #endif
1039 
1040 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
1041 
1042 static const struct of_device_id dsa_of_match_table[] = {
1043 	{ .compatible = "brcm,bcm7445-switch-v4.0" },
1044 	{ .compatible = "marvell,dsa", },
1045 	{}
1046 };
1047 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
1048 
1049 static struct platform_driver dsa_driver = {
1050 	.probe		= dsa_probe,
1051 	.remove		= dsa_remove,
1052 	.shutdown	= dsa_shutdown,
1053 	.driver = {
1054 		.name	= "dsa",
1055 		.of_match_table = dsa_of_match_table,
1056 		.pm	= &dsa_pm_ops,
1057 	},
1058 };
1059 
1060 static int __init dsa_init_module(void)
1061 {
1062 	int rc;
1063 
1064 	register_netdevice_notifier(&dsa_netdevice_nb);
1065 
1066 	rc = platform_driver_register(&dsa_driver);
1067 	if (rc)
1068 		return rc;
1069 
1070 	dev_add_pack(&dsa_pack_type);
1071 
1072 	return 0;
1073 }
1074 module_init(dsa_init_module);
1075 
1076 static void __exit dsa_cleanup_module(void)
1077 {
1078 	unregister_netdevice_notifier(&dsa_netdevice_nb);
1079 	dev_remove_pack(&dsa_pack_type);
1080 	platform_driver_unregister(&dsa_driver);
1081 }
1082 module_exit(dsa_cleanup_module);
1083 
1084 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
1085 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
1086 MODULE_LICENSE("GPL");
1087 MODULE_ALIAS("platform:dsa");
1088