xref: /openbmc/linux/net/dsa/dsa.c (revision cc8bbe1a)
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 
33 /* switch driver registration ***********************************************/
34 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
35 static LIST_HEAD(dsa_switch_drivers);
36 
37 void register_switch_driver(struct dsa_switch_driver *drv)
38 {
39 	mutex_lock(&dsa_switch_drivers_mutex);
40 	list_add_tail(&drv->list, &dsa_switch_drivers);
41 	mutex_unlock(&dsa_switch_drivers_mutex);
42 }
43 EXPORT_SYMBOL_GPL(register_switch_driver);
44 
45 void unregister_switch_driver(struct dsa_switch_driver *drv)
46 {
47 	mutex_lock(&dsa_switch_drivers_mutex);
48 	list_del_init(&drv->list);
49 	mutex_unlock(&dsa_switch_drivers_mutex);
50 }
51 EXPORT_SYMBOL_GPL(unregister_switch_driver);
52 
53 static struct dsa_switch_driver *
54 dsa_switch_probe(struct device *host_dev, int sw_addr, char **_name)
55 {
56 	struct dsa_switch_driver *ret;
57 	struct list_head *list;
58 	char *name;
59 
60 	ret = NULL;
61 	name = NULL;
62 
63 	mutex_lock(&dsa_switch_drivers_mutex);
64 	list_for_each(list, &dsa_switch_drivers) {
65 		struct dsa_switch_driver *drv;
66 
67 		drv = list_entry(list, struct dsa_switch_driver, list);
68 
69 		name = drv->probe(host_dev, sw_addr);
70 		if (name != NULL) {
71 			ret = drv;
72 			break;
73 		}
74 	}
75 	mutex_unlock(&dsa_switch_drivers_mutex);
76 
77 	*_name = name;
78 
79 	return ret;
80 }
81 
82 /* hwmon support ************************************************************/
83 
84 #ifdef CONFIG_NET_DSA_HWMON
85 
86 static ssize_t temp1_input_show(struct device *dev,
87 				struct device_attribute *attr, char *buf)
88 {
89 	struct dsa_switch *ds = dev_get_drvdata(dev);
90 	int temp, ret;
91 
92 	ret = ds->drv->get_temp(ds, &temp);
93 	if (ret < 0)
94 		return ret;
95 
96 	return sprintf(buf, "%d\n", temp * 1000);
97 }
98 static DEVICE_ATTR_RO(temp1_input);
99 
100 static ssize_t temp1_max_show(struct device *dev,
101 			      struct device_attribute *attr, char *buf)
102 {
103 	struct dsa_switch *ds = dev_get_drvdata(dev);
104 	int temp, ret;
105 
106 	ret = ds->drv->get_temp_limit(ds, &temp);
107 	if (ret < 0)
108 		return ret;
109 
110 	return sprintf(buf, "%d\n", temp * 1000);
111 }
112 
113 static ssize_t temp1_max_store(struct device *dev,
114 			       struct device_attribute *attr, const char *buf,
115 			       size_t count)
116 {
117 	struct dsa_switch *ds = dev_get_drvdata(dev);
118 	int temp, ret;
119 
120 	ret = kstrtoint(buf, 0, &temp);
121 	if (ret < 0)
122 		return ret;
123 
124 	ret = ds->drv->set_temp_limit(ds, DIV_ROUND_CLOSEST(temp, 1000));
125 	if (ret < 0)
126 		return ret;
127 
128 	return count;
129 }
130 static DEVICE_ATTR_RW(temp1_max);
131 
132 static ssize_t temp1_max_alarm_show(struct device *dev,
133 				    struct device_attribute *attr, char *buf)
134 {
135 	struct dsa_switch *ds = dev_get_drvdata(dev);
136 	bool alarm;
137 	int ret;
138 
139 	ret = ds->drv->get_temp_alarm(ds, &alarm);
140 	if (ret < 0)
141 		return ret;
142 
143 	return sprintf(buf, "%d\n", alarm);
144 }
145 static DEVICE_ATTR_RO(temp1_max_alarm);
146 
147 static struct attribute *dsa_hwmon_attrs[] = {
148 	&dev_attr_temp1_input.attr,	/* 0 */
149 	&dev_attr_temp1_max.attr,	/* 1 */
150 	&dev_attr_temp1_max_alarm.attr,	/* 2 */
151 	NULL
152 };
153 
154 static umode_t dsa_hwmon_attrs_visible(struct kobject *kobj,
155 				       struct attribute *attr, int index)
156 {
157 	struct device *dev = container_of(kobj, struct device, kobj);
158 	struct dsa_switch *ds = dev_get_drvdata(dev);
159 	struct dsa_switch_driver *drv = ds->drv;
160 	umode_t mode = attr->mode;
161 
162 	if (index == 1) {
163 		if (!drv->get_temp_limit)
164 			mode = 0;
165 		else if (!drv->set_temp_limit)
166 			mode &= ~S_IWUSR;
167 	} else if (index == 2 && !drv->get_temp_alarm) {
168 		mode = 0;
169 	}
170 	return mode;
171 }
172 
173 static const struct attribute_group dsa_hwmon_group = {
174 	.attrs = dsa_hwmon_attrs,
175 	.is_visible = dsa_hwmon_attrs_visible,
176 };
177 __ATTRIBUTE_GROUPS(dsa_hwmon);
178 
179 #endif /* CONFIG_NET_DSA_HWMON */
180 
181 /* basic switch operations **************************************************/
182 static int dsa_cpu_dsa_setup(struct dsa_switch *ds, struct net_device *master)
183 {
184 	struct dsa_chip_data *cd = ds->pd;
185 	struct device_node *port_dn;
186 	struct phy_device *phydev;
187 	int ret, port, mode;
188 
189 	for (port = 0; port < DSA_MAX_PORTS; port++) {
190 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
191 			continue;
192 
193 		port_dn = cd->port_dn[port];
194 		if (of_phy_is_fixed_link(port_dn)) {
195 			ret = of_phy_register_fixed_link(port_dn);
196 			if (ret) {
197 				netdev_err(master,
198 					   "failed to register fixed PHY\n");
199 				return ret;
200 			}
201 			phydev = of_phy_find_device(port_dn);
202 
203 			mode = of_get_phy_mode(port_dn);
204 			if (mode < 0)
205 				mode = PHY_INTERFACE_MODE_NA;
206 			phydev->interface = mode;
207 
208 			genphy_config_init(phydev);
209 			genphy_read_status(phydev);
210 			if (ds->drv->adjust_link)
211 				ds->drv->adjust_link(ds, port, phydev);
212 		}
213 	}
214 	return 0;
215 }
216 
217 static int dsa_switch_setup_one(struct dsa_switch *ds, struct device *parent)
218 {
219 	struct dsa_switch_driver *drv = ds->drv;
220 	struct dsa_switch_tree *dst = ds->dst;
221 	struct dsa_chip_data *pd = ds->pd;
222 	bool valid_name_found = false;
223 	int index = ds->index;
224 	int i, ret;
225 
226 	/*
227 	 * Validate supplied switch configuration.
228 	 */
229 	for (i = 0; i < DSA_MAX_PORTS; i++) {
230 		char *name;
231 
232 		name = pd->port_names[i];
233 		if (name == NULL)
234 			continue;
235 
236 		if (!strcmp(name, "cpu")) {
237 			if (dst->cpu_switch != -1) {
238 				netdev_err(dst->master_netdev,
239 					   "multiple cpu ports?!\n");
240 				ret = -EINVAL;
241 				goto out;
242 			}
243 			dst->cpu_switch = index;
244 			dst->cpu_port = i;
245 		} else if (!strcmp(name, "dsa")) {
246 			ds->dsa_port_mask |= 1 << i;
247 		} else {
248 			ds->phys_port_mask |= 1 << i;
249 		}
250 		valid_name_found = true;
251 	}
252 
253 	if (!valid_name_found && i == DSA_MAX_PORTS) {
254 		ret = -EINVAL;
255 		goto out;
256 	}
257 
258 	/* Make the built-in MII bus mask match the number of ports,
259 	 * switch drivers can override this later
260 	 */
261 	ds->phys_mii_mask = ds->phys_port_mask;
262 
263 	/*
264 	 * If the CPU connects to this switch, set the switch tree
265 	 * tagging protocol to the preferred tagging format of this
266 	 * switch.
267 	 */
268 	if (dst->cpu_switch == index) {
269 		switch (ds->tag_protocol) {
270 #ifdef CONFIG_NET_DSA_TAG_DSA
271 		case DSA_TAG_PROTO_DSA:
272 			dst->rcv = dsa_netdev_ops.rcv;
273 			break;
274 #endif
275 #ifdef CONFIG_NET_DSA_TAG_EDSA
276 		case DSA_TAG_PROTO_EDSA:
277 			dst->rcv = edsa_netdev_ops.rcv;
278 			break;
279 #endif
280 #ifdef CONFIG_NET_DSA_TAG_TRAILER
281 		case DSA_TAG_PROTO_TRAILER:
282 			dst->rcv = trailer_netdev_ops.rcv;
283 			break;
284 #endif
285 #ifdef CONFIG_NET_DSA_TAG_BRCM
286 		case DSA_TAG_PROTO_BRCM:
287 			dst->rcv = brcm_netdev_ops.rcv;
288 			break;
289 #endif
290 		case DSA_TAG_PROTO_NONE:
291 			break;
292 		default:
293 			ret = -ENOPROTOOPT;
294 			goto out;
295 		}
296 
297 		dst->tag_protocol = ds->tag_protocol;
298 	}
299 
300 	/*
301 	 * Do basic register setup.
302 	 */
303 	ret = drv->setup(ds);
304 	if (ret < 0)
305 		goto out;
306 
307 	ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
308 	if (ret < 0)
309 		goto out;
310 
311 	ds->slave_mii_bus = devm_mdiobus_alloc(parent);
312 	if (ds->slave_mii_bus == NULL) {
313 		ret = -ENOMEM;
314 		goto out;
315 	}
316 	dsa_slave_mii_bus_init(ds);
317 
318 	ret = mdiobus_register(ds->slave_mii_bus);
319 	if (ret < 0)
320 		goto out;
321 
322 
323 	/*
324 	 * Create network devices for physical switch ports.
325 	 */
326 	for (i = 0; i < DSA_MAX_PORTS; i++) {
327 		if (!(ds->phys_port_mask & (1 << i)))
328 			continue;
329 
330 		ret = dsa_slave_create(ds, parent, i, pd->port_names[i]);
331 		if (ret < 0) {
332 			netdev_err(dst->master_netdev, "[%d]: can't create dsa slave device for port %d(%s): %d\n",
333 				   index, i, pd->port_names[i], ret);
334 			ret = 0;
335 		}
336 	}
337 
338 	/* Perform configuration of the CPU and DSA ports */
339 	ret = dsa_cpu_dsa_setup(ds, dst->master_netdev);
340 	if (ret < 0) {
341 		netdev_err(dst->master_netdev, "[%d] : can't configure CPU and DSA ports\n",
342 			   index);
343 		ret = 0;
344 	}
345 
346 #ifdef CONFIG_NET_DSA_HWMON
347 	/* If the switch provides a temperature sensor,
348 	 * register with hardware monitoring subsystem.
349 	 * Treat registration error as non-fatal and ignore it.
350 	 */
351 	if (drv->get_temp) {
352 		const char *netname = netdev_name(dst->master_netdev);
353 		char hname[IFNAMSIZ + 1];
354 		int i, j;
355 
356 		/* Create valid hwmon 'name' attribute */
357 		for (i = j = 0; i < IFNAMSIZ && netname[i]; i++) {
358 			if (isalnum(netname[i]))
359 				hname[j++] = netname[i];
360 		}
361 		hname[j] = '\0';
362 		scnprintf(ds->hwmon_name, sizeof(ds->hwmon_name), "%s_dsa%d",
363 			  hname, index);
364 		ds->hwmon_dev = hwmon_device_register_with_groups(NULL,
365 					ds->hwmon_name, ds, dsa_hwmon_groups);
366 		if (IS_ERR(ds->hwmon_dev))
367 			ds->hwmon_dev = NULL;
368 	}
369 #endif /* CONFIG_NET_DSA_HWMON */
370 
371 	return ret;
372 
373 out:
374 	return ret;
375 }
376 
377 static struct dsa_switch *
378 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
379 		 struct device *parent, struct device *host_dev)
380 {
381 	struct dsa_chip_data *pd = dst->pd->chip + index;
382 	struct dsa_switch_driver *drv;
383 	struct dsa_switch *ds;
384 	int ret;
385 	char *name;
386 
387 	/*
388 	 * Probe for switch model.
389 	 */
390 	drv = dsa_switch_probe(host_dev, pd->sw_addr, &name);
391 	if (drv == NULL) {
392 		netdev_err(dst->master_netdev, "[%d]: could not detect attached switch\n",
393 			   index);
394 		return ERR_PTR(-EINVAL);
395 	}
396 	netdev_info(dst->master_netdev, "[%d]: detected a %s switch\n",
397 		    index, name);
398 
399 
400 	/*
401 	 * Allocate and initialise switch state.
402 	 */
403 	ds = devm_kzalloc(parent, sizeof(*ds) + drv->priv_size, GFP_KERNEL);
404 	if (ds == NULL)
405 		return ERR_PTR(-ENOMEM);
406 
407 	ds->dst = dst;
408 	ds->index = index;
409 	ds->pd = pd;
410 	ds->drv = drv;
411 	ds->tag_protocol = drv->tag_protocol;
412 	ds->master_dev = host_dev;
413 
414 	ret = dsa_switch_setup_one(ds, parent);
415 	if (ret)
416 		return ERR_PTR(ret);
417 
418 	return ds;
419 }
420 
421 static void dsa_switch_destroy(struct dsa_switch *ds)
422 {
423 	struct device_node *port_dn;
424 	struct phy_device *phydev;
425 	struct dsa_chip_data *cd = ds->pd;
426 	int port;
427 
428 #ifdef CONFIG_NET_DSA_HWMON
429 	if (ds->hwmon_dev)
430 		hwmon_device_unregister(ds->hwmon_dev);
431 #endif
432 
433 	/* Disable configuration of the CPU and DSA ports */
434 	for (port = 0; port < DSA_MAX_PORTS; port++) {
435 		if (!(dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port)))
436 			continue;
437 
438 		port_dn = cd->port_dn[port];
439 		if (of_phy_is_fixed_link(port_dn)) {
440 			phydev = of_phy_find_device(port_dn);
441 			if (phydev) {
442 				int addr = phydev->mdio.addr;
443 
444 				phy_device_free(phydev);
445 				of_node_put(port_dn);
446 				fixed_phy_del(addr);
447 			}
448 		}
449 	}
450 
451 	/* Destroy network devices for physical switch ports. */
452 	for (port = 0; port < DSA_MAX_PORTS; port++) {
453 		if (!(ds->phys_port_mask & (1 << port)))
454 			continue;
455 
456 		if (!ds->ports[port])
457 			continue;
458 
459 		dsa_slave_destroy(ds->ports[port]);
460 	}
461 
462 	mdiobus_unregister(ds->slave_mii_bus);
463 }
464 
465 #ifdef CONFIG_PM_SLEEP
466 static int dsa_switch_suspend(struct dsa_switch *ds)
467 {
468 	int i, ret = 0;
469 
470 	/* Suspend slave network devices */
471 	for (i = 0; i < DSA_MAX_PORTS; i++) {
472 		if (!dsa_is_port_initialized(ds, i))
473 			continue;
474 
475 		ret = dsa_slave_suspend(ds->ports[i]);
476 		if (ret)
477 			return ret;
478 	}
479 
480 	if (ds->drv->suspend)
481 		ret = ds->drv->suspend(ds);
482 
483 	return ret;
484 }
485 
486 static int dsa_switch_resume(struct dsa_switch *ds)
487 {
488 	int i, ret = 0;
489 
490 	if (ds->drv->resume)
491 		ret = ds->drv->resume(ds);
492 
493 	if (ret)
494 		return ret;
495 
496 	/* Resume slave network devices */
497 	for (i = 0; i < DSA_MAX_PORTS; i++) {
498 		if (!dsa_is_port_initialized(ds, i))
499 			continue;
500 
501 		ret = dsa_slave_resume(ds->ports[i]);
502 		if (ret)
503 			return ret;
504 	}
505 
506 	return 0;
507 }
508 #endif
509 
510 /* platform driver init and cleanup *****************************************/
511 static int dev_is_class(struct device *dev, void *class)
512 {
513 	if (dev->class != NULL && !strcmp(dev->class->name, class))
514 		return 1;
515 
516 	return 0;
517 }
518 
519 static struct device *dev_find_class(struct device *parent, char *class)
520 {
521 	if (dev_is_class(parent, class)) {
522 		get_device(parent);
523 		return parent;
524 	}
525 
526 	return device_find_child(parent, class, dev_is_class);
527 }
528 
529 struct mii_bus *dsa_host_dev_to_mii_bus(struct device *dev)
530 {
531 	struct device *d;
532 
533 	d = dev_find_class(dev, "mdio_bus");
534 	if (d != NULL) {
535 		struct mii_bus *bus;
536 
537 		bus = to_mii_bus(d);
538 		put_device(d);
539 
540 		return bus;
541 	}
542 
543 	return NULL;
544 }
545 EXPORT_SYMBOL_GPL(dsa_host_dev_to_mii_bus);
546 
547 static struct net_device *dev_to_net_device(struct device *dev)
548 {
549 	struct device *d;
550 
551 	d = dev_find_class(dev, "net");
552 	if (d != NULL) {
553 		struct net_device *nd;
554 
555 		nd = to_net_dev(d);
556 		dev_hold(nd);
557 		put_device(d);
558 
559 		return nd;
560 	}
561 
562 	return NULL;
563 }
564 
565 #ifdef CONFIG_OF
566 static int dsa_of_setup_routing_table(struct dsa_platform_data *pd,
567 					struct dsa_chip_data *cd,
568 					int chip_index, int port_index,
569 					struct device_node *link)
570 {
571 	const __be32 *reg;
572 	int link_sw_addr;
573 	struct device_node *parent_sw;
574 	int len;
575 
576 	parent_sw = of_get_parent(link);
577 	if (!parent_sw)
578 		return -EINVAL;
579 
580 	reg = of_get_property(parent_sw, "reg", &len);
581 	if (!reg || (len != sizeof(*reg) * 2))
582 		return -EINVAL;
583 
584 	/*
585 	 * Get the destination switch number from the second field of its 'reg'
586 	 * property, i.e. for "reg = <0x19 1>" sw_addr is '1'.
587 	 */
588 	link_sw_addr = be32_to_cpup(reg + 1);
589 
590 	if (link_sw_addr >= pd->nr_chips)
591 		return -EINVAL;
592 
593 	/* First time routing table allocation */
594 	if (!cd->rtable) {
595 		cd->rtable = kmalloc_array(pd->nr_chips, sizeof(s8),
596 					   GFP_KERNEL);
597 		if (!cd->rtable)
598 			return -ENOMEM;
599 
600 		/* default to no valid uplink/downlink */
601 		memset(cd->rtable, -1, pd->nr_chips * sizeof(s8));
602 	}
603 
604 	cd->rtable[link_sw_addr] = port_index;
605 
606 	return 0;
607 }
608 
609 static int dsa_of_probe_links(struct dsa_platform_data *pd,
610 			      struct dsa_chip_data *cd,
611 			      int chip_index, int port_index,
612 			      struct device_node *port,
613 			      const char *port_name)
614 {
615 	struct device_node *link;
616 	int link_index;
617 	int ret;
618 
619 	for (link_index = 0;; link_index++) {
620 		link = of_parse_phandle(port, "link", link_index);
621 		if (!link)
622 			break;
623 
624 		if (!strcmp(port_name, "dsa") && pd->nr_chips > 1) {
625 			ret = dsa_of_setup_routing_table(pd, cd, chip_index,
626 							 port_index, link);
627 			if (ret)
628 				return ret;
629 		}
630 	}
631 	return 0;
632 }
633 
634 static void dsa_of_free_platform_data(struct dsa_platform_data *pd)
635 {
636 	int i;
637 	int port_index;
638 
639 	for (i = 0; i < pd->nr_chips; i++) {
640 		port_index = 0;
641 		while (port_index < DSA_MAX_PORTS) {
642 			kfree(pd->chip[i].port_names[port_index]);
643 			port_index++;
644 		}
645 		kfree(pd->chip[i].rtable);
646 
647 		/* Drop our reference to the MDIO bus device */
648 		if (pd->chip[i].host_dev)
649 			put_device(pd->chip[i].host_dev);
650 	}
651 	kfree(pd->chip);
652 }
653 
654 static int dsa_of_probe(struct device *dev)
655 {
656 	struct device_node *np = dev->of_node;
657 	struct device_node *child, *mdio, *ethernet, *port;
658 	struct mii_bus *mdio_bus, *mdio_bus_switch;
659 	struct net_device *ethernet_dev;
660 	struct dsa_platform_data *pd;
661 	struct dsa_chip_data *cd;
662 	const char *port_name;
663 	int chip_index, port_index;
664 	const unsigned int *sw_addr, *port_reg;
665 	int gpio;
666 	enum of_gpio_flags of_flags;
667 	unsigned long flags;
668 	u32 eeprom_len;
669 	int ret;
670 
671 	mdio = of_parse_phandle(np, "dsa,mii-bus", 0);
672 	if (!mdio)
673 		return -EINVAL;
674 
675 	mdio_bus = of_mdio_find_bus(mdio);
676 	if (!mdio_bus)
677 		return -EPROBE_DEFER;
678 
679 	ethernet = of_parse_phandle(np, "dsa,ethernet", 0);
680 	if (!ethernet) {
681 		ret = -EINVAL;
682 		goto out_put_mdio;
683 	}
684 
685 	ethernet_dev = of_find_net_device_by_node(ethernet);
686 	if (!ethernet_dev) {
687 		ret = -EPROBE_DEFER;
688 		goto out_put_mdio;
689 	}
690 
691 	pd = kzalloc(sizeof(*pd), GFP_KERNEL);
692 	if (!pd) {
693 		ret = -ENOMEM;
694 		goto out_put_ethernet;
695 	}
696 
697 	dev->platform_data = pd;
698 	pd->of_netdev = ethernet_dev;
699 	pd->nr_chips = of_get_available_child_count(np);
700 	if (pd->nr_chips > DSA_MAX_SWITCHES)
701 		pd->nr_chips = DSA_MAX_SWITCHES;
702 
703 	pd->chip = kcalloc(pd->nr_chips, sizeof(struct dsa_chip_data),
704 			   GFP_KERNEL);
705 	if (!pd->chip) {
706 		ret = -ENOMEM;
707 		goto out_free;
708 	}
709 
710 	chip_index = -1;
711 	for_each_available_child_of_node(np, child) {
712 		chip_index++;
713 		cd = &pd->chip[chip_index];
714 
715 		cd->of_node = child;
716 
717 		/* When assigning the host device, increment its refcount */
718 		cd->host_dev = get_device(&mdio_bus->dev);
719 
720 		sw_addr = of_get_property(child, "reg", NULL);
721 		if (!sw_addr)
722 			continue;
723 
724 		cd->sw_addr = be32_to_cpup(sw_addr);
725 		if (cd->sw_addr >= PHY_MAX_ADDR)
726 			continue;
727 
728 		if (!of_property_read_u32(child, "eeprom-length", &eeprom_len))
729 			cd->eeprom_len = eeprom_len;
730 
731 		mdio = of_parse_phandle(child, "mii-bus", 0);
732 		if (mdio) {
733 			mdio_bus_switch = of_mdio_find_bus(mdio);
734 			if (!mdio_bus_switch) {
735 				ret = -EPROBE_DEFER;
736 				goto out_free_chip;
737 			}
738 
739 			/* Drop the mdio_bus device ref, replacing the host
740 			 * device with the mdio_bus_switch device, keeping
741 			 * the refcount from of_mdio_find_bus() above.
742 			 */
743 			put_device(cd->host_dev);
744 			cd->host_dev = &mdio_bus_switch->dev;
745 		}
746 		gpio = of_get_named_gpio_flags(child, "reset-gpios", 0,
747 					       &of_flags);
748 		if (gpio_is_valid(gpio)) {
749 			flags = (of_flags == OF_GPIO_ACTIVE_LOW ?
750 				 GPIOF_ACTIVE_LOW : 0);
751 			ret = devm_gpio_request_one(dev, gpio, flags,
752 						    "switch_reset");
753 			if (ret)
754 				goto out_free_chip;
755 
756 			cd->reset = gpio_to_desc(gpio);
757 			gpiod_direction_output(cd->reset, 0);
758 		}
759 
760 		for_each_available_child_of_node(child, port) {
761 			port_reg = of_get_property(port, "reg", NULL);
762 			if (!port_reg)
763 				continue;
764 
765 			port_index = be32_to_cpup(port_reg);
766 			if (port_index >= DSA_MAX_PORTS)
767 				break;
768 
769 			port_name = of_get_property(port, "label", NULL);
770 			if (!port_name)
771 				continue;
772 
773 			cd->port_dn[port_index] = port;
774 
775 			cd->port_names[port_index] = kstrdup(port_name,
776 					GFP_KERNEL);
777 			if (!cd->port_names[port_index]) {
778 				ret = -ENOMEM;
779 				goto out_free_chip;
780 			}
781 
782 			ret = dsa_of_probe_links(pd, cd, chip_index,
783 						 port_index, port, port_name);
784 			if (ret)
785 				goto out_free_chip;
786 
787 		}
788 	}
789 
790 	/* The individual chips hold their own refcount on the mdio bus,
791 	 * so drop ours */
792 	put_device(&mdio_bus->dev);
793 
794 	return 0;
795 
796 out_free_chip:
797 	dsa_of_free_platform_data(pd);
798 out_free:
799 	kfree(pd);
800 	dev->platform_data = NULL;
801 out_put_ethernet:
802 	put_device(&ethernet_dev->dev);
803 out_put_mdio:
804 	put_device(&mdio_bus->dev);
805 	return ret;
806 }
807 
808 static void dsa_of_remove(struct device *dev)
809 {
810 	struct dsa_platform_data *pd = dev->platform_data;
811 
812 	if (!dev->of_node)
813 		return;
814 
815 	dsa_of_free_platform_data(pd);
816 	put_device(&pd->of_netdev->dev);
817 	kfree(pd);
818 }
819 #else
820 static inline int dsa_of_probe(struct device *dev)
821 {
822 	return 0;
823 }
824 
825 static inline void dsa_of_remove(struct device *dev)
826 {
827 }
828 #endif
829 
830 static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
831 			 struct device *parent, struct dsa_platform_data *pd)
832 {
833 	int i;
834 	unsigned configured = 0;
835 
836 	dst->pd = pd;
837 	dst->master_netdev = dev;
838 	dst->cpu_switch = -1;
839 	dst->cpu_port = -1;
840 
841 	for (i = 0; i < pd->nr_chips; i++) {
842 		struct dsa_switch *ds;
843 
844 		ds = dsa_switch_setup(dst, i, parent, pd->chip[i].host_dev);
845 		if (IS_ERR(ds)) {
846 			netdev_err(dev, "[%d]: couldn't create dsa switch instance (error %ld)\n",
847 				   i, PTR_ERR(ds));
848 			continue;
849 		}
850 
851 		dst->ds[i] = ds;
852 
853 		++configured;
854 	}
855 
856 	/*
857 	 * If no switch was found, exit cleanly
858 	 */
859 	if (!configured)
860 		return -EPROBE_DEFER;
861 
862 	/*
863 	 * If we use a tagging format that doesn't have an ethertype
864 	 * field, make sure that all packets from this point on get
865 	 * sent to the tag format's receive function.
866 	 */
867 	wmb();
868 	dev->dsa_ptr = (void *)dst;
869 
870 	return 0;
871 }
872 
873 static int dsa_probe(struct platform_device *pdev)
874 {
875 	struct dsa_platform_data *pd = pdev->dev.platform_data;
876 	struct net_device *dev;
877 	struct dsa_switch_tree *dst;
878 	int ret;
879 
880 	pr_notice_once("Distributed Switch Architecture driver version %s\n",
881 		       dsa_driver_version);
882 
883 	if (pdev->dev.of_node) {
884 		ret = dsa_of_probe(&pdev->dev);
885 		if (ret)
886 			return ret;
887 
888 		pd = pdev->dev.platform_data;
889 	}
890 
891 	if (pd == NULL || (pd->netdev == NULL && pd->of_netdev == NULL))
892 		return -EINVAL;
893 
894 	if (pd->of_netdev) {
895 		dev = pd->of_netdev;
896 		dev_hold(dev);
897 	} else {
898 		dev = dev_to_net_device(pd->netdev);
899 	}
900 	if (dev == NULL) {
901 		ret = -EPROBE_DEFER;
902 		goto out;
903 	}
904 
905 	if (dev->dsa_ptr != NULL) {
906 		dev_put(dev);
907 		ret = -EEXIST;
908 		goto out;
909 	}
910 
911 	dst = devm_kzalloc(&pdev->dev, sizeof(*dst), GFP_KERNEL);
912 	if (dst == NULL) {
913 		dev_put(dev);
914 		ret = -ENOMEM;
915 		goto out;
916 	}
917 
918 	platform_set_drvdata(pdev, dst);
919 
920 	ret = dsa_setup_dst(dst, dev, &pdev->dev, pd);
921 	if (ret) {
922 		dev_put(dev);
923 		goto out;
924 	}
925 
926 	return 0;
927 
928 out:
929 	dsa_of_remove(&pdev->dev);
930 
931 	return ret;
932 }
933 
934 static void dsa_remove_dst(struct dsa_switch_tree *dst)
935 {
936 	int i;
937 
938 	for (i = 0; i < dst->pd->nr_chips; i++) {
939 		struct dsa_switch *ds = dst->ds[i];
940 
941 		if (ds)
942 			dsa_switch_destroy(ds);
943 	}
944 
945 	dev_put(dst->master_netdev);
946 }
947 
948 static int dsa_remove(struct platform_device *pdev)
949 {
950 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
951 
952 	dsa_remove_dst(dst);
953 	dsa_of_remove(&pdev->dev);
954 
955 	return 0;
956 }
957 
958 static void dsa_shutdown(struct platform_device *pdev)
959 {
960 }
961 
962 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
963 			  struct packet_type *pt, struct net_device *orig_dev)
964 {
965 	struct dsa_switch_tree *dst = dev->dsa_ptr;
966 
967 	if (unlikely(dst == NULL)) {
968 		kfree_skb(skb);
969 		return 0;
970 	}
971 
972 	return dst->rcv(skb, dev, pt, orig_dev);
973 }
974 
975 static struct packet_type dsa_pack_type __read_mostly = {
976 	.type	= cpu_to_be16(ETH_P_XDSA),
977 	.func	= dsa_switch_rcv,
978 };
979 
980 static struct notifier_block dsa_netdevice_nb __read_mostly = {
981 	.notifier_call	= dsa_slave_netdevice_event,
982 };
983 
984 #ifdef CONFIG_PM_SLEEP
985 static int dsa_suspend(struct device *d)
986 {
987 	struct platform_device *pdev = to_platform_device(d);
988 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
989 	int i, ret = 0;
990 
991 	dst->master_netdev->dsa_ptr = NULL;
992 
993 	/* If we used a tagging format that doesn't have an ethertype
994 	 * field, make sure that all packets from this point get sent
995 	 * without the tag and go through the regular receive path.
996 	 */
997 	wmb();
998 
999 	for (i = 0; i < dst->pd->nr_chips; i++) {
1000 		struct dsa_switch *ds = dst->ds[i];
1001 
1002 		if (ds != NULL)
1003 			ret = dsa_switch_suspend(ds);
1004 	}
1005 
1006 	return ret;
1007 }
1008 
1009 static int dsa_resume(struct device *d)
1010 {
1011 	struct platform_device *pdev = to_platform_device(d);
1012 	struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
1013 	int i, ret = 0;
1014 
1015 	for (i = 0; i < dst->pd->nr_chips; i++) {
1016 		struct dsa_switch *ds = dst->ds[i];
1017 
1018 		if (ds != NULL)
1019 			ret = dsa_switch_resume(ds);
1020 	}
1021 
1022 	return ret;
1023 }
1024 #endif
1025 
1026 static SIMPLE_DEV_PM_OPS(dsa_pm_ops, dsa_suspend, dsa_resume);
1027 
1028 static const struct of_device_id dsa_of_match_table[] = {
1029 	{ .compatible = "brcm,bcm7445-switch-v4.0" },
1030 	{ .compatible = "marvell,dsa", },
1031 	{}
1032 };
1033 MODULE_DEVICE_TABLE(of, dsa_of_match_table);
1034 
1035 static struct platform_driver dsa_driver = {
1036 	.probe		= dsa_probe,
1037 	.remove		= dsa_remove,
1038 	.shutdown	= dsa_shutdown,
1039 	.driver = {
1040 		.name	= "dsa",
1041 		.of_match_table = dsa_of_match_table,
1042 		.pm	= &dsa_pm_ops,
1043 	},
1044 };
1045 
1046 static int __init dsa_init_module(void)
1047 {
1048 	int rc;
1049 
1050 	register_netdevice_notifier(&dsa_netdevice_nb);
1051 
1052 	rc = platform_driver_register(&dsa_driver);
1053 	if (rc)
1054 		return rc;
1055 
1056 	dev_add_pack(&dsa_pack_type);
1057 
1058 	return 0;
1059 }
1060 module_init(dsa_init_module);
1061 
1062 static void __exit dsa_cleanup_module(void)
1063 {
1064 	unregister_netdevice_notifier(&dsa_netdevice_nb);
1065 	dev_remove_pack(&dsa_pack_type);
1066 	platform_driver_unregister(&dsa_driver);
1067 }
1068 module_exit(dsa_cleanup_module);
1069 
1070 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
1071 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
1072 MODULE_LICENSE("GPL");
1073 MODULE_ALIAS("platform:dsa");
1074