Merge branch 'topic/user-access-begin' into next
[linux-2.6-microblaze.git] / net / dsa / dsa2.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/dsa/dsa2.c - Hardware switch handling, binding version 2
4  * Copyright (c) 2008-2009 Marvell Semiconductor
5  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
6  * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
7  */
8
9 #include <linux/device.h>
10 #include <linux/err.h>
11 #include <linux/list.h>
12 #include <linux/netdevice.h>
13 #include <linux/slab.h>
14 #include <linux/rtnetlink.h>
15 #include <linux/of.h>
16 #include <linux/of_net.h>
17 #include <net/devlink.h>
18
19 #include "dsa_priv.h"
20
21 static LIST_HEAD(dsa_tree_list);
22 static DEFINE_MUTEX(dsa2_mutex);
23
24 static const struct devlink_ops dsa_devlink_ops = {
25 };
26
27 static struct dsa_switch_tree *dsa_tree_find(int index)
28 {
29         struct dsa_switch_tree *dst;
30
31         list_for_each_entry(dst, &dsa_tree_list, list)
32                 if (dst->index == index)
33                         return dst;
34
35         return NULL;
36 }
37
38 static struct dsa_switch_tree *dsa_tree_alloc(int index)
39 {
40         struct dsa_switch_tree *dst;
41
42         dst = kzalloc(sizeof(*dst), GFP_KERNEL);
43         if (!dst)
44                 return NULL;
45
46         dst->index = index;
47
48         INIT_LIST_HEAD(&dst->rtable);
49
50         INIT_LIST_HEAD(&dst->ports);
51
52         INIT_LIST_HEAD(&dst->list);
53         list_add_tail(&dst->list, &dsa_tree_list);
54
55         kref_init(&dst->refcount);
56
57         return dst;
58 }
59
60 static void dsa_tree_free(struct dsa_switch_tree *dst)
61 {
62         list_del(&dst->list);
63         kfree(dst);
64 }
65
66 static struct dsa_switch_tree *dsa_tree_get(struct dsa_switch_tree *dst)
67 {
68         if (dst)
69                 kref_get(&dst->refcount);
70
71         return dst;
72 }
73
74 static struct dsa_switch_tree *dsa_tree_touch(int index)
75 {
76         struct dsa_switch_tree *dst;
77
78         dst = dsa_tree_find(index);
79         if (dst)
80                 return dsa_tree_get(dst);
81         else
82                 return dsa_tree_alloc(index);
83 }
84
85 static void dsa_tree_release(struct kref *ref)
86 {
87         struct dsa_switch_tree *dst;
88
89         dst = container_of(ref, struct dsa_switch_tree, refcount);
90
91         dsa_tree_free(dst);
92 }
93
94 static void dsa_tree_put(struct dsa_switch_tree *dst)
95 {
96         if (dst)
97                 kref_put(&dst->refcount, dsa_tree_release);
98 }
99
100 static bool dsa_port_is_dsa(struct dsa_port *port)
101 {
102         return port->type == DSA_PORT_TYPE_DSA;
103 }
104
105 static bool dsa_port_is_cpu(struct dsa_port *port)
106 {
107         return port->type == DSA_PORT_TYPE_CPU;
108 }
109
110 static bool dsa_port_is_user(struct dsa_port *dp)
111 {
112         return dp->type == DSA_PORT_TYPE_USER;
113 }
114
115 static struct dsa_port *dsa_tree_find_port_by_node(struct dsa_switch_tree *dst,
116                                                    struct device_node *dn)
117 {
118         struct dsa_port *dp;
119
120         list_for_each_entry(dp, &dst->ports, list)
121                 if (dp->dn == dn)
122                         return dp;
123
124         return NULL;
125 }
126
127 static struct dsa_link *dsa_link_touch(struct dsa_port *dp,
128                                        struct dsa_port *link_dp)
129 {
130         struct dsa_switch *ds = dp->ds;
131         struct dsa_switch_tree *dst;
132         struct dsa_link *dl;
133
134         dst = ds->dst;
135
136         list_for_each_entry(dl, &dst->rtable, list)
137                 if (dl->dp == dp && dl->link_dp == link_dp)
138                         return dl;
139
140         dl = kzalloc(sizeof(*dl), GFP_KERNEL);
141         if (!dl)
142                 return NULL;
143
144         dl->dp = dp;
145         dl->link_dp = link_dp;
146
147         INIT_LIST_HEAD(&dl->list);
148         list_add_tail(&dl->list, &dst->rtable);
149
150         return dl;
151 }
152
153 static bool dsa_port_setup_routing_table(struct dsa_port *dp)
154 {
155         struct dsa_switch *ds = dp->ds;
156         struct dsa_switch_tree *dst = ds->dst;
157         struct device_node *dn = dp->dn;
158         struct of_phandle_iterator it;
159         struct dsa_port *link_dp;
160         struct dsa_link *dl;
161         int err;
162
163         of_for_each_phandle(&it, err, dn, "link", NULL, 0) {
164                 link_dp = dsa_tree_find_port_by_node(dst, it.node);
165                 if (!link_dp) {
166                         of_node_put(it.node);
167                         return false;
168                 }
169
170                 dl = dsa_link_touch(dp, link_dp);
171                 if (!dl) {
172                         of_node_put(it.node);
173                         return false;
174                 }
175         }
176
177         return true;
178 }
179
180 static bool dsa_tree_setup_routing_table(struct dsa_switch_tree *dst)
181 {
182         bool complete = true;
183         struct dsa_port *dp;
184
185         list_for_each_entry(dp, &dst->ports, list) {
186                 if (dsa_port_is_dsa(dp)) {
187                         complete = dsa_port_setup_routing_table(dp);
188                         if (!complete)
189                                 break;
190                 }
191         }
192
193         return complete;
194 }
195
196 static struct dsa_port *dsa_tree_find_first_cpu(struct dsa_switch_tree *dst)
197 {
198         struct dsa_port *dp;
199
200         list_for_each_entry(dp, &dst->ports, list)
201                 if (dsa_port_is_cpu(dp))
202                         return dp;
203
204         return NULL;
205 }
206
207 static int dsa_tree_setup_default_cpu(struct dsa_switch_tree *dst)
208 {
209         struct dsa_port *cpu_dp, *dp;
210
211         cpu_dp = dsa_tree_find_first_cpu(dst);
212         if (!cpu_dp) {
213                 pr_err("DSA: tree %d has no CPU port\n", dst->index);
214                 return -EINVAL;
215         }
216
217         /* Assign the default CPU port to all ports of the fabric */
218         list_for_each_entry(dp, &dst->ports, list)
219                 if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
220                         dp->cpu_dp = cpu_dp;
221
222         return 0;
223 }
224
225 static void dsa_tree_teardown_default_cpu(struct dsa_switch_tree *dst)
226 {
227         struct dsa_port *dp;
228
229         list_for_each_entry(dp, &dst->ports, list)
230                 if (dsa_port_is_user(dp) || dsa_port_is_dsa(dp))
231                         dp->cpu_dp = NULL;
232 }
233
234 static int dsa_port_setup(struct dsa_port *dp)
235 {
236         struct dsa_switch *ds = dp->ds;
237         struct dsa_switch_tree *dst = ds->dst;
238         const unsigned char *id = (const unsigned char *)&dst->index;
239         const unsigned char len = sizeof(dst->index);
240         struct devlink_port *dlp = &dp->devlink_port;
241         bool dsa_port_link_registered = false;
242         bool devlink_port_registered = false;
243         struct devlink *dl = ds->devlink;
244         bool dsa_port_enabled = false;
245         int err = 0;
246
247         if (dp->setup)
248                 return 0;
249
250         switch (dp->type) {
251         case DSA_PORT_TYPE_UNUSED:
252                 dsa_port_disable(dp);
253                 break;
254         case DSA_PORT_TYPE_CPU:
255                 memset(dlp, 0, sizeof(*dlp));
256                 devlink_port_attrs_set(dlp, DEVLINK_PORT_FLAVOUR_CPU,
257                                        dp->index, false, 0, id, len);
258                 err = devlink_port_register(dl, dlp, dp->index);
259                 if (err)
260                         break;
261                 devlink_port_registered = true;
262
263                 err = dsa_port_link_register_of(dp);
264                 if (err)
265                         break;
266                 dsa_port_link_registered = true;
267
268                 err = dsa_port_enable(dp, NULL);
269                 if (err)
270                         break;
271                 dsa_port_enabled = true;
272
273                 break;
274         case DSA_PORT_TYPE_DSA:
275                 memset(dlp, 0, sizeof(*dlp));
276                 devlink_port_attrs_set(dlp, DEVLINK_PORT_FLAVOUR_DSA,
277                                        dp->index, false, 0, id, len);
278                 err = devlink_port_register(dl, dlp, dp->index);
279                 if (err)
280                         break;
281                 devlink_port_registered = true;
282
283                 err = dsa_port_link_register_of(dp);
284                 if (err)
285                         break;
286                 dsa_port_link_registered = true;
287
288                 err = dsa_port_enable(dp, NULL);
289                 if (err)
290                         break;
291                 dsa_port_enabled = true;
292
293                 break;
294         case DSA_PORT_TYPE_USER:
295                 memset(dlp, 0, sizeof(*dlp));
296                 devlink_port_attrs_set(dlp, DEVLINK_PORT_FLAVOUR_PHYSICAL,
297                                        dp->index, false, 0, id, len);
298                 err = devlink_port_register(dl, dlp, dp->index);
299                 if (err)
300                         break;
301                 devlink_port_registered = true;
302
303                 dp->mac = of_get_mac_address(dp->dn);
304                 err = dsa_slave_create(dp);
305                 if (err)
306                         break;
307
308                 devlink_port_type_eth_set(dlp, dp->slave);
309                 break;
310         }
311
312         if (err && dsa_port_enabled)
313                 dsa_port_disable(dp);
314         if (err && dsa_port_link_registered)
315                 dsa_port_link_unregister_of(dp);
316         if (err && devlink_port_registered)
317                 devlink_port_unregister(dlp);
318         if (err)
319                 return err;
320
321         dp->setup = true;
322
323         return 0;
324 }
325
326 static void dsa_port_teardown(struct dsa_port *dp)
327 {
328         struct devlink_port *dlp = &dp->devlink_port;
329
330         if (!dp->setup)
331                 return;
332
333         switch (dp->type) {
334         case DSA_PORT_TYPE_UNUSED:
335                 break;
336         case DSA_PORT_TYPE_CPU:
337                 dsa_port_disable(dp);
338                 dsa_tag_driver_put(dp->tag_ops);
339                 devlink_port_unregister(dlp);
340                 dsa_port_link_unregister_of(dp);
341                 break;
342         case DSA_PORT_TYPE_DSA:
343                 dsa_port_disable(dp);
344                 devlink_port_unregister(dlp);
345                 dsa_port_link_unregister_of(dp);
346                 break;
347         case DSA_PORT_TYPE_USER:
348                 devlink_port_unregister(dlp);
349                 if (dp->slave) {
350                         dsa_slave_destroy(dp->slave);
351                         dp->slave = NULL;
352                 }
353                 break;
354         }
355
356         dp->setup = false;
357 }
358
359 static int dsa_switch_setup(struct dsa_switch *ds)
360 {
361         struct dsa_devlink_priv *dl_priv;
362         int err;
363
364         if (ds->setup)
365                 return 0;
366
367         /* Initialize ds->phys_mii_mask before registering the slave MDIO bus
368          * driver and before ops->setup() has run, since the switch drivers and
369          * the slave MDIO bus driver rely on these values for probing PHY
370          * devices or not
371          */
372         ds->phys_mii_mask |= dsa_user_ports(ds);
373
374         /* Add the switch to devlink before calling setup, so that setup can
375          * add dpipe tables
376          */
377         ds->devlink = devlink_alloc(&dsa_devlink_ops, sizeof(*dl_priv));
378         if (!ds->devlink)
379                 return -ENOMEM;
380         dl_priv = devlink_priv(ds->devlink);
381         dl_priv->ds = ds;
382
383         err = devlink_register(ds->devlink, ds->dev);
384         if (err)
385                 goto free_devlink;
386
387         err = dsa_switch_register_notifier(ds);
388         if (err)
389                 goto unregister_devlink;
390
391         err = ds->ops->setup(ds);
392         if (err < 0)
393                 goto unregister_notifier;
394
395         devlink_params_publish(ds->devlink);
396
397         if (!ds->slave_mii_bus && ds->ops->phy_read) {
398                 ds->slave_mii_bus = devm_mdiobus_alloc(ds->dev);
399                 if (!ds->slave_mii_bus) {
400                         err = -ENOMEM;
401                         goto unregister_notifier;
402                 }
403
404                 dsa_slave_mii_bus_init(ds);
405
406                 err = mdiobus_register(ds->slave_mii_bus);
407                 if (err < 0)
408                         goto unregister_notifier;
409         }
410
411         ds->setup = true;
412
413         return 0;
414
415 unregister_notifier:
416         dsa_switch_unregister_notifier(ds);
417 unregister_devlink:
418         devlink_unregister(ds->devlink);
419 free_devlink:
420         devlink_free(ds->devlink);
421         ds->devlink = NULL;
422
423         return err;
424 }
425
426 static void dsa_switch_teardown(struct dsa_switch *ds)
427 {
428         if (!ds->setup)
429                 return;
430
431         if (ds->slave_mii_bus && ds->ops->phy_read)
432                 mdiobus_unregister(ds->slave_mii_bus);
433
434         dsa_switch_unregister_notifier(ds);
435
436         if (ds->ops->teardown)
437                 ds->ops->teardown(ds);
438
439         if (ds->devlink) {
440                 devlink_unregister(ds->devlink);
441                 devlink_free(ds->devlink);
442                 ds->devlink = NULL;
443         }
444
445         ds->setup = false;
446 }
447
448 static int dsa_tree_setup_switches(struct dsa_switch_tree *dst)
449 {
450         struct dsa_port *dp;
451         int err;
452
453         list_for_each_entry(dp, &dst->ports, list) {
454                 err = dsa_switch_setup(dp->ds);
455                 if (err)
456                         goto teardown;
457         }
458
459         list_for_each_entry(dp, &dst->ports, list) {
460                 err = dsa_port_setup(dp);
461                 if (err)
462                         goto teardown;
463         }
464
465         return 0;
466
467 teardown:
468         list_for_each_entry(dp, &dst->ports, list)
469                 dsa_port_teardown(dp);
470
471         list_for_each_entry(dp, &dst->ports, list)
472                 dsa_switch_teardown(dp->ds);
473
474         return err;
475 }
476
477 static void dsa_tree_teardown_switches(struct dsa_switch_tree *dst)
478 {
479         struct dsa_port *dp;
480
481         list_for_each_entry(dp, &dst->ports, list)
482                 dsa_port_teardown(dp);
483
484         list_for_each_entry(dp, &dst->ports, list)
485                 dsa_switch_teardown(dp->ds);
486 }
487
488 static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
489 {
490         struct dsa_port *dp;
491         int err;
492
493         list_for_each_entry(dp, &dst->ports, list) {
494                 if (dsa_port_is_cpu(dp)) {
495                         err = dsa_master_setup(dp->master, dp);
496                         if (err)
497                                 return err;
498                 }
499         }
500
501         return 0;
502 }
503
504 static void dsa_tree_teardown_master(struct dsa_switch_tree *dst)
505 {
506         struct dsa_port *dp;
507
508         list_for_each_entry(dp, &dst->ports, list)
509                 if (dsa_port_is_cpu(dp))
510                         dsa_master_teardown(dp->master);
511 }
512
513 static int dsa_tree_setup(struct dsa_switch_tree *dst)
514 {
515         bool complete;
516         int err;
517
518         if (dst->setup) {
519                 pr_err("DSA: tree %d already setup! Disjoint trees?\n",
520                        dst->index);
521                 return -EEXIST;
522         }
523
524         complete = dsa_tree_setup_routing_table(dst);
525         if (!complete)
526                 return 0;
527
528         err = dsa_tree_setup_default_cpu(dst);
529         if (err)
530                 return err;
531
532         err = dsa_tree_setup_switches(dst);
533         if (err)
534                 goto teardown_default_cpu;
535
536         err = dsa_tree_setup_master(dst);
537         if (err)
538                 goto teardown_switches;
539
540         dst->setup = true;
541
542         pr_info("DSA: tree %d setup\n", dst->index);
543
544         return 0;
545
546 teardown_switches:
547         dsa_tree_teardown_switches(dst);
548 teardown_default_cpu:
549         dsa_tree_teardown_default_cpu(dst);
550
551         return err;
552 }
553
554 static void dsa_tree_teardown(struct dsa_switch_tree *dst)
555 {
556         struct dsa_link *dl, *next;
557
558         if (!dst->setup)
559                 return;
560
561         dsa_tree_teardown_master(dst);
562
563         dsa_tree_teardown_switches(dst);
564
565         dsa_tree_teardown_default_cpu(dst);
566
567         list_for_each_entry_safe(dl, next, &dst->rtable, list) {
568                 list_del(&dl->list);
569                 kfree(dl);
570         }
571
572         pr_info("DSA: tree %d torn down\n", dst->index);
573
574         dst->setup = false;
575 }
576
577 static struct dsa_port *dsa_port_touch(struct dsa_switch *ds, int index)
578 {
579         struct dsa_switch_tree *dst = ds->dst;
580         struct dsa_port *dp;
581
582         list_for_each_entry(dp, &dst->ports, list)
583                 if (dp->ds == ds && dp->index == index)
584                         return dp;
585
586         dp = kzalloc(sizeof(*dp), GFP_KERNEL);
587         if (!dp)
588                 return NULL;
589
590         dp->ds = ds;
591         dp->index = index;
592
593         INIT_LIST_HEAD(&dp->list);
594         list_add_tail(&dp->list, &dst->ports);
595
596         return dp;
597 }
598
599 static int dsa_port_parse_user(struct dsa_port *dp, const char *name)
600 {
601         if (!name)
602                 name = "eth%d";
603
604         dp->type = DSA_PORT_TYPE_USER;
605         dp->name = name;
606
607         return 0;
608 }
609
610 static int dsa_port_parse_dsa(struct dsa_port *dp)
611 {
612         dp->type = DSA_PORT_TYPE_DSA;
613
614         return 0;
615 }
616
617 static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master)
618 {
619         struct dsa_switch *ds = dp->ds;
620         struct dsa_switch_tree *dst = ds->dst;
621         const struct dsa_device_ops *tag_ops;
622         enum dsa_tag_protocol tag_protocol;
623
624         tag_protocol = ds->ops->get_tag_protocol(ds, dp->index);
625         tag_ops = dsa_tag_driver_get(tag_protocol);
626         if (IS_ERR(tag_ops)) {
627                 if (PTR_ERR(tag_ops) == -ENOPROTOOPT)
628                         return -EPROBE_DEFER;
629                 dev_warn(ds->dev, "No tagger for this switch\n");
630                 return PTR_ERR(tag_ops);
631         }
632
633         dp->type = DSA_PORT_TYPE_CPU;
634         dp->filter = tag_ops->filter;
635         dp->rcv = tag_ops->rcv;
636         dp->tag_ops = tag_ops;
637         dp->master = master;
638         dp->dst = dst;
639
640         return 0;
641 }
642
643 static int dsa_port_parse_of(struct dsa_port *dp, struct device_node *dn)
644 {
645         struct device_node *ethernet = of_parse_phandle(dn, "ethernet", 0);
646         const char *name = of_get_property(dn, "label", NULL);
647         bool link = of_property_read_bool(dn, "link");
648
649         dp->dn = dn;
650
651         if (ethernet) {
652                 struct net_device *master;
653
654                 master = of_find_net_device_by_node(ethernet);
655                 if (!master)
656                         return -EPROBE_DEFER;
657
658                 return dsa_port_parse_cpu(dp, master);
659         }
660
661         if (link)
662                 return dsa_port_parse_dsa(dp);
663
664         return dsa_port_parse_user(dp, name);
665 }
666
667 static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
668                                      struct device_node *dn)
669 {
670         struct device_node *ports, *port;
671         struct dsa_port *dp;
672         int err = 0;
673         u32 reg;
674
675         ports = of_get_child_by_name(dn, "ports");
676         if (!ports) {
677                 dev_err(ds->dev, "no ports child node found\n");
678                 return -EINVAL;
679         }
680
681         for_each_available_child_of_node(ports, port) {
682                 err = of_property_read_u32(port, "reg", &reg);
683                 if (err)
684                         goto out_put_node;
685
686                 if (reg >= ds->num_ports) {
687                         err = -EINVAL;
688                         goto out_put_node;
689                 }
690
691                 dp = dsa_to_port(ds, reg);
692
693                 err = dsa_port_parse_of(dp, port);
694                 if (err)
695                         goto out_put_node;
696         }
697
698 out_put_node:
699         of_node_put(ports);
700         return err;
701 }
702
703 static int dsa_switch_parse_member_of(struct dsa_switch *ds,
704                                       struct device_node *dn)
705 {
706         u32 m[2] = { 0, 0 };
707         int sz;
708
709         /* Don't error out if this optional property isn't found */
710         sz = of_property_read_variable_u32_array(dn, "dsa,member", m, 2, 2);
711         if (sz < 0 && sz != -EINVAL)
712                 return sz;
713
714         ds->index = m[1];
715
716         ds->dst = dsa_tree_touch(m[0]);
717         if (!ds->dst)
718                 return -ENOMEM;
719
720         return 0;
721 }
722
723 static int dsa_switch_touch_ports(struct dsa_switch *ds)
724 {
725         struct dsa_port *dp;
726         int port;
727
728         for (port = 0; port < ds->num_ports; port++) {
729                 dp = dsa_port_touch(ds, port);
730                 if (!dp)
731                         return -ENOMEM;
732         }
733
734         return 0;
735 }
736
737 static int dsa_switch_parse_of(struct dsa_switch *ds, struct device_node *dn)
738 {
739         int err;
740
741         err = dsa_switch_parse_member_of(ds, dn);
742         if (err)
743                 return err;
744
745         err = dsa_switch_touch_ports(ds);
746         if (err)
747                 return err;
748
749         return dsa_switch_parse_ports_of(ds, dn);
750 }
751
752 static int dsa_port_parse(struct dsa_port *dp, const char *name,
753                           struct device *dev)
754 {
755         if (!strcmp(name, "cpu")) {
756                 struct net_device *master;
757
758                 master = dsa_dev_to_net_device(dev);
759                 if (!master)
760                         return -EPROBE_DEFER;
761
762                 dev_put(master);
763
764                 return dsa_port_parse_cpu(dp, master);
765         }
766
767         if (!strcmp(name, "dsa"))
768                 return dsa_port_parse_dsa(dp);
769
770         return dsa_port_parse_user(dp, name);
771 }
772
773 static int dsa_switch_parse_ports(struct dsa_switch *ds,
774                                   struct dsa_chip_data *cd)
775 {
776         bool valid_name_found = false;
777         struct dsa_port *dp;
778         struct device *dev;
779         const char *name;
780         unsigned int i;
781         int err;
782
783         for (i = 0; i < DSA_MAX_PORTS; i++) {
784                 name = cd->port_names[i];
785                 dev = cd->netdev[i];
786                 dp = dsa_to_port(ds, i);
787
788                 if (!name)
789                         continue;
790
791                 err = dsa_port_parse(dp, name, dev);
792                 if (err)
793                         return err;
794
795                 valid_name_found = true;
796         }
797
798         if (!valid_name_found && i == DSA_MAX_PORTS)
799                 return -EINVAL;
800
801         return 0;
802 }
803
804 static int dsa_switch_parse(struct dsa_switch *ds, struct dsa_chip_data *cd)
805 {
806         int err;
807
808         ds->cd = cd;
809
810         /* We don't support interconnected switches nor multiple trees via
811          * platform data, so this is the unique switch of the tree.
812          */
813         ds->index = 0;
814         ds->dst = dsa_tree_touch(0);
815         if (!ds->dst)
816                 return -ENOMEM;
817
818         err = dsa_switch_touch_ports(ds);
819         if (err)
820                 return err;
821
822         return dsa_switch_parse_ports(ds, cd);
823 }
824
825 static int dsa_switch_probe(struct dsa_switch *ds)
826 {
827         struct dsa_switch_tree *dst;
828         struct dsa_chip_data *pdata;
829         struct device_node *np;
830         int err;
831
832         if (!ds->dev)
833                 return -ENODEV;
834
835         pdata = ds->dev->platform_data;
836         np = ds->dev->of_node;
837
838         if (!ds->num_ports)
839                 return -EINVAL;
840
841         if (np)
842                 err = dsa_switch_parse_of(ds, np);
843         else if (pdata)
844                 err = dsa_switch_parse(ds, pdata);
845         else
846                 err = -ENODEV;
847
848         if (err)
849                 return err;
850
851         dst = ds->dst;
852         dsa_tree_get(dst);
853         err = dsa_tree_setup(dst);
854         if (err)
855                 dsa_tree_put(dst);
856
857         return err;
858 }
859
860 int dsa_register_switch(struct dsa_switch *ds)
861 {
862         int err;
863
864         mutex_lock(&dsa2_mutex);
865         err = dsa_switch_probe(ds);
866         dsa_tree_put(ds->dst);
867         mutex_unlock(&dsa2_mutex);
868
869         return err;
870 }
871 EXPORT_SYMBOL_GPL(dsa_register_switch);
872
873 static void dsa_switch_remove(struct dsa_switch *ds)
874 {
875         struct dsa_switch_tree *dst = ds->dst;
876         struct dsa_port *dp, *next;
877
878         dsa_tree_teardown(dst);
879
880         list_for_each_entry_safe(dp, next, &dst->ports, list) {
881                 list_del(&dp->list);
882                 kfree(dp);
883         }
884
885         dsa_tree_put(dst);
886 }
887
888 void dsa_unregister_switch(struct dsa_switch *ds)
889 {
890         mutex_lock(&dsa2_mutex);
891         dsa_switch_remove(ds);
892         mutex_unlock(&dsa2_mutex);
893 }
894 EXPORT_SYMBOL_GPL(dsa_unregister_switch);