Linux-libre 5.7.5-gnu
[librecmc/linux-libre.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 DEFINE_MUTEX(dsa2_mutex);
22 LIST_HEAD(dsa_tree_list);
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                         continue;
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 enum dsa_tag_protocol dsa_get_tag_protocol(struct dsa_port *dp,
618                                                   struct net_device *master)
619 {
620         enum dsa_tag_protocol tag_protocol = DSA_TAG_PROTO_NONE;
621         struct dsa_switch *mds, *ds = dp->ds;
622         unsigned int mdp_upstream;
623         struct dsa_port *mdp;
624
625         /* It is possible to stack DSA switches onto one another when that
626          * happens the switch driver may want to know if its tagging protocol
627          * is going to work in such a configuration.
628          */
629         if (dsa_slave_dev_check(master)) {
630                 mdp = dsa_slave_to_port(master);
631                 mds = mdp->ds;
632                 mdp_upstream = dsa_upstream_port(mds, mdp->index);
633                 tag_protocol = mds->ops->get_tag_protocol(mds, mdp_upstream,
634                                                           DSA_TAG_PROTO_NONE);
635         }
636
637         /* If the master device is not itself a DSA slave in a disjoint DSA
638          * tree, then return immediately.
639          */
640         return ds->ops->get_tag_protocol(ds, dp->index, tag_protocol);
641 }
642
643 static int dsa_port_parse_cpu(struct dsa_port *dp, struct net_device *master)
644 {
645         struct dsa_switch *ds = dp->ds;
646         struct dsa_switch_tree *dst = ds->dst;
647         const struct dsa_device_ops *tag_ops;
648         enum dsa_tag_protocol tag_protocol;
649
650         tag_protocol = dsa_get_tag_protocol(dp, master);
651         tag_ops = dsa_tag_driver_get(tag_protocol);
652         if (IS_ERR(tag_ops)) {
653                 if (PTR_ERR(tag_ops) == -ENOPROTOOPT)
654                         return -EPROBE_DEFER;
655                 dev_warn(ds->dev, "No tagger for this switch\n");
656                 dp->master = NULL;
657                 return PTR_ERR(tag_ops);
658         }
659
660         dp->master = master;
661         dp->type = DSA_PORT_TYPE_CPU;
662         dp->filter = tag_ops->filter;
663         dp->rcv = tag_ops->rcv;
664         dp->tag_ops = tag_ops;
665         dp->dst = dst;
666
667         return 0;
668 }
669
670 static int dsa_port_parse_of(struct dsa_port *dp, struct device_node *dn)
671 {
672         struct device_node *ethernet = of_parse_phandle(dn, "ethernet", 0);
673         const char *name = of_get_property(dn, "label", NULL);
674         bool link = of_property_read_bool(dn, "link");
675
676         dp->dn = dn;
677
678         if (ethernet) {
679                 struct net_device *master;
680
681                 master = of_find_net_device_by_node(ethernet);
682                 if (!master)
683                         return -EPROBE_DEFER;
684
685                 return dsa_port_parse_cpu(dp, master);
686         }
687
688         if (link)
689                 return dsa_port_parse_dsa(dp);
690
691         return dsa_port_parse_user(dp, name);
692 }
693
694 static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
695                                      struct device_node *dn)
696 {
697         struct device_node *ports, *port;
698         struct dsa_port *dp;
699         int err = 0;
700         u32 reg;
701
702         ports = of_get_child_by_name(dn, "ports");
703         if (!ports) {
704                 dev_err(ds->dev, "no ports child node found\n");
705                 return -EINVAL;
706         }
707
708         for_each_available_child_of_node(ports, port) {
709                 err = of_property_read_u32(port, "reg", &reg);
710                 if (err)
711                         goto out_put_node;
712
713                 if (reg >= ds->num_ports) {
714                         err = -EINVAL;
715                         goto out_put_node;
716                 }
717
718                 dp = dsa_to_port(ds, reg);
719
720                 err = dsa_port_parse_of(dp, port);
721                 if (err)
722                         goto out_put_node;
723         }
724
725 out_put_node:
726         of_node_put(ports);
727         return err;
728 }
729
730 static int dsa_switch_parse_member_of(struct dsa_switch *ds,
731                                       struct device_node *dn)
732 {
733         u32 m[2] = { 0, 0 };
734         int sz;
735
736         /* Don't error out if this optional property isn't found */
737         sz = of_property_read_variable_u32_array(dn, "dsa,member", m, 2, 2);
738         if (sz < 0 && sz != -EINVAL)
739                 return sz;
740
741         ds->index = m[1];
742
743         ds->dst = dsa_tree_touch(m[0]);
744         if (!ds->dst)
745                 return -ENOMEM;
746
747         return 0;
748 }
749
750 static int dsa_switch_touch_ports(struct dsa_switch *ds)
751 {
752         struct dsa_port *dp;
753         int port;
754
755         for (port = 0; port < ds->num_ports; port++) {
756                 dp = dsa_port_touch(ds, port);
757                 if (!dp)
758                         return -ENOMEM;
759         }
760
761         return 0;
762 }
763
764 static int dsa_switch_parse_of(struct dsa_switch *ds, struct device_node *dn)
765 {
766         int err;
767
768         err = dsa_switch_parse_member_of(ds, dn);
769         if (err)
770                 return err;
771
772         err = dsa_switch_touch_ports(ds);
773         if (err)
774                 return err;
775
776         return dsa_switch_parse_ports_of(ds, dn);
777 }
778
779 static int dsa_port_parse(struct dsa_port *dp, const char *name,
780                           struct device *dev)
781 {
782         if (!strcmp(name, "cpu")) {
783                 struct net_device *master;
784
785                 master = dsa_dev_to_net_device(dev);
786                 if (!master)
787                         return -EPROBE_DEFER;
788
789                 dev_put(master);
790
791                 return dsa_port_parse_cpu(dp, master);
792         }
793
794         if (!strcmp(name, "dsa"))
795                 return dsa_port_parse_dsa(dp);
796
797         return dsa_port_parse_user(dp, name);
798 }
799
800 static int dsa_switch_parse_ports(struct dsa_switch *ds,
801                                   struct dsa_chip_data *cd)
802 {
803         bool valid_name_found = false;
804         struct dsa_port *dp;
805         struct device *dev;
806         const char *name;
807         unsigned int i;
808         int err;
809
810         for (i = 0; i < DSA_MAX_PORTS; i++) {
811                 name = cd->port_names[i];
812                 dev = cd->netdev[i];
813                 dp = dsa_to_port(ds, i);
814
815                 if (!name)
816                         continue;
817
818                 err = dsa_port_parse(dp, name, dev);
819                 if (err)
820                         return err;
821
822                 valid_name_found = true;
823         }
824
825         if (!valid_name_found && i == DSA_MAX_PORTS)
826                 return -EINVAL;
827
828         return 0;
829 }
830
831 static int dsa_switch_parse(struct dsa_switch *ds, struct dsa_chip_data *cd)
832 {
833         int err;
834
835         ds->cd = cd;
836
837         /* We don't support interconnected switches nor multiple trees via
838          * platform data, so this is the unique switch of the tree.
839          */
840         ds->index = 0;
841         ds->dst = dsa_tree_touch(0);
842         if (!ds->dst)
843                 return -ENOMEM;
844
845         err = dsa_switch_touch_ports(ds);
846         if (err)
847                 return err;
848
849         return dsa_switch_parse_ports(ds, cd);
850 }
851
852 static void dsa_switch_release_ports(struct dsa_switch *ds)
853 {
854         struct dsa_switch_tree *dst = ds->dst;
855         struct dsa_port *dp, *next;
856
857         list_for_each_entry_safe(dp, next, &dst->ports, list) {
858                 if (dp->ds != ds)
859                         continue;
860                 list_del(&dp->list);
861                 kfree(dp);
862         }
863 }
864
865 static int dsa_switch_probe(struct dsa_switch *ds)
866 {
867         struct dsa_switch_tree *dst;
868         struct dsa_chip_data *pdata;
869         struct device_node *np;
870         int err;
871
872         if (!ds->dev)
873                 return -ENODEV;
874
875         pdata = ds->dev->platform_data;
876         np = ds->dev->of_node;
877
878         if (!ds->num_ports)
879                 return -EINVAL;
880
881         if (np) {
882                 err = dsa_switch_parse_of(ds, np);
883                 if (err)
884                         dsa_switch_release_ports(ds);
885         } else if (pdata) {
886                 err = dsa_switch_parse(ds, pdata);
887                 if (err)
888                         dsa_switch_release_ports(ds);
889         } else {
890                 err = -ENODEV;
891         }
892
893         if (err)
894                 return err;
895
896         dst = ds->dst;
897         dsa_tree_get(dst);
898         err = dsa_tree_setup(dst);
899         if (err) {
900                 dsa_switch_release_ports(ds);
901                 dsa_tree_put(dst);
902         }
903
904         return err;
905 }
906
907 int dsa_register_switch(struct dsa_switch *ds)
908 {
909         int err;
910
911         mutex_lock(&dsa2_mutex);
912         err = dsa_switch_probe(ds);
913         dsa_tree_put(ds->dst);
914         mutex_unlock(&dsa2_mutex);
915
916         return err;
917 }
918 EXPORT_SYMBOL_GPL(dsa_register_switch);
919
920 static void dsa_switch_remove(struct dsa_switch *ds)
921 {
922         struct dsa_switch_tree *dst = ds->dst;
923
924         dsa_tree_teardown(dst);
925         dsa_switch_release_ports(ds);
926         dsa_tree_put(dst);
927 }
928
929 void dsa_unregister_switch(struct dsa_switch *ds)
930 {
931         mutex_lock(&dsa2_mutex);
932         dsa_switch_remove(ds);
933         mutex_unlock(&dsa2_mutex);
934 }
935 EXPORT_SYMBOL_GPL(dsa_unregister_switch);