1 /*
2 * net/dsa/dsa.c - Hardware switch handling
3 * Copyright (c) 2008-2009 Marvell Semiconductor
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11 #include <linux/list.h>
12 #include <linux/netdevice.h>
13 #include <linux/platform_device.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <net/dsa.h>
17 #include "dsa_priv.h"
18
19 char dsa_driver_version[] = "0.1";
20
21
22 /* switch driver registration ***********************************************/
23 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
24 static LIST_HEAD(dsa_switch_drivers);
25
register_switch_driver(struct dsa_switch_driver * drv)26 void register_switch_driver(struct dsa_switch_driver *drv)
27 {
28 mutex_lock(&dsa_switch_drivers_mutex);
29 list_add_tail(&drv->list, &dsa_switch_drivers);
30 mutex_unlock(&dsa_switch_drivers_mutex);
31 }
32 EXPORT_SYMBOL_GPL(register_switch_driver);
33
unregister_switch_driver(struct dsa_switch_driver * drv)34 void unregister_switch_driver(struct dsa_switch_driver *drv)
35 {
36 mutex_lock(&dsa_switch_drivers_mutex);
37 list_del_init(&drv->list);
38 mutex_unlock(&dsa_switch_drivers_mutex);
39 }
40 EXPORT_SYMBOL_GPL(unregister_switch_driver);
41
42 static struct dsa_switch_driver *
dsa_switch_probe(struct mii_bus * bus,int sw_addr,char ** _name)43 dsa_switch_probe(struct mii_bus *bus, int sw_addr, char **_name)
44 {
45 struct dsa_switch_driver *ret;
46 struct list_head *list;
47 char *name;
48
49 ret = NULL;
50 name = NULL;
51
52 mutex_lock(&dsa_switch_drivers_mutex);
53 list_for_each(list, &dsa_switch_drivers) {
54 struct dsa_switch_driver *drv;
55
56 drv = list_entry(list, struct dsa_switch_driver, list);
57
58 name = drv->probe(bus, sw_addr);
59 if (name != NULL) {
60 ret = drv;
61 break;
62 }
63 }
64 mutex_unlock(&dsa_switch_drivers_mutex);
65
66 *_name = name;
67
68 return ret;
69 }
70
71
72 /* basic switch operations **************************************************/
73 static struct dsa_switch *
dsa_switch_setup(struct dsa_switch_tree * dst,int index,struct device * parent,struct mii_bus * bus)74 dsa_switch_setup(struct dsa_switch_tree *dst, int index,
75 struct device *parent, struct mii_bus *bus)
76 {
77 struct dsa_chip_data *pd = dst->pd->chip + index;
78 struct dsa_switch_driver *drv;
79 struct dsa_switch *ds;
80 int ret;
81 char *name;
82 int i;
83
84 /*
85 * Probe for switch model.
86 */
87 drv = dsa_switch_probe(bus, pd->sw_addr, &name);
88 if (drv == NULL) {
89 printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
90 dst->master_netdev->name, index);
91 return ERR_PTR(-EINVAL);
92 }
93 printk(KERN_INFO "%s[%d]: detected a %s switch\n",
94 dst->master_netdev->name, index, name);
95
96
97 /*
98 * Allocate and initialise switch state.
99 */
100 ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
101 if (ds == NULL)
102 return ERR_PTR(-ENOMEM);
103
104 ds->dst = dst;
105 ds->index = index;
106 ds->pd = dst->pd->chip + index;
107 ds->drv = drv;
108 ds->master_mii_bus = bus;
109
110
111 /*
112 * Validate supplied switch configuration.
113 */
114 for (i = 0; i < DSA_MAX_PORTS; i++) {
115 char *name;
116
117 name = pd->port_names[i];
118 if (name == NULL)
119 continue;
120
121 if (!strcmp(name, "cpu")) {
122 if (dst->cpu_switch != -1) {
123 printk(KERN_ERR "multiple cpu ports?!\n");
124 ret = -EINVAL;
125 goto out;
126 }
127 dst->cpu_switch = index;
128 dst->cpu_port = i;
129 } else if (!strcmp(name, "dsa")) {
130 ds->dsa_port_mask |= 1 << i;
131 } else {
132 ds->phys_port_mask |= 1 << i;
133 }
134 }
135
136
137 /*
138 * If the CPU connects to this switch, set the switch tree
139 * tagging protocol to the preferred tagging format of this
140 * switch.
141 */
142 if (ds->dst->cpu_switch == index)
143 ds->dst->tag_protocol = drv->tag_protocol;
144
145
146 /*
147 * Do basic register setup.
148 */
149 ret = drv->setup(ds);
150 if (ret < 0)
151 goto out;
152
153 ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
154 if (ret < 0)
155 goto out;
156
157 ds->slave_mii_bus = mdiobus_alloc();
158 if (ds->slave_mii_bus == NULL) {
159 ret = -ENOMEM;
160 goto out;
161 }
162 dsa_slave_mii_bus_init(ds);
163
164 ret = mdiobus_register(ds->slave_mii_bus);
165 if (ret < 0)
166 goto out_free;
167
168
169 /*
170 * Create network devices for physical switch ports.
171 */
172 for (i = 0; i < DSA_MAX_PORTS; i++) {
173 struct net_device *slave_dev;
174
175 if (!(ds->phys_port_mask & (1 << i)))
176 continue;
177
178 slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
179 if (slave_dev == NULL) {
180 printk(KERN_ERR "%s[%d]: can't create dsa "
181 "slave device for port %d(%s)\n",
182 dst->master_netdev->name,
183 index, i, pd->port_names[i]);
184 continue;
185 }
186
187 ds->ports[i] = slave_dev;
188 }
189
190 return ds;
191
192 out_free:
193 mdiobus_free(ds->slave_mii_bus);
194 out:
195 kfree(ds);
196 return ERR_PTR(ret);
197 }
198
dsa_switch_destroy(struct dsa_switch * ds)199 static void dsa_switch_destroy(struct dsa_switch *ds)
200 {
201 }
202
203
204 /* link polling *************************************************************/
dsa_link_poll_work(struct work_struct * ugly)205 static void dsa_link_poll_work(struct work_struct *ugly)
206 {
207 struct dsa_switch_tree *dst;
208 int i;
209
210 dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
211
212 for (i = 0; i < dst->pd->nr_chips; i++) {
213 struct dsa_switch *ds = dst->ds[i];
214
215 if (ds != NULL && ds->drv->poll_link != NULL)
216 ds->drv->poll_link(ds);
217 }
218
219 mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
220 }
221
dsa_link_poll_timer(unsigned long _dst)222 static void dsa_link_poll_timer(unsigned long _dst)
223 {
224 struct dsa_switch_tree *dst = (void *)_dst;
225
226 schedule_work(&dst->link_poll_work);
227 }
228
229
230 /* platform driver init and cleanup *****************************************/
dev_is_class(struct device * dev,void * class)231 static int dev_is_class(struct device *dev, void *class)
232 {
233 if (dev->class != NULL && !strcmp(dev->class->name, class))
234 return 1;
235
236 return 0;
237 }
238
dev_find_class(struct device * parent,char * class)239 static struct device *dev_find_class(struct device *parent, char *class)
240 {
241 if (dev_is_class(parent, class)) {
242 get_device(parent);
243 return parent;
244 }
245
246 return device_find_child(parent, class, dev_is_class);
247 }
248
dev_to_mii_bus(struct device * dev)249 static struct mii_bus *dev_to_mii_bus(struct device *dev)
250 {
251 struct device *d;
252
253 d = dev_find_class(dev, "mdio_bus");
254 if (d != NULL) {
255 struct mii_bus *bus;
256
257 bus = to_mii_bus(d);
258 put_device(d);
259
260 return bus;
261 }
262
263 return NULL;
264 }
265
dev_to_net_device(struct device * dev)266 static struct net_device *dev_to_net_device(struct device *dev)
267 {
268 struct device *d;
269
270 d = dev_find_class(dev, "net");
271 if (d != NULL) {
272 struct net_device *nd;
273
274 nd = to_net_dev(d);
275 dev_hold(nd);
276 put_device(d);
277
278 return nd;
279 }
280
281 return NULL;
282 }
283
dsa_probe(struct platform_device * pdev)284 static int dsa_probe(struct platform_device *pdev)
285 {
286 static int dsa_version_printed;
287 struct dsa_platform_data *pd = pdev->dev.platform_data;
288 struct net_device *dev;
289 struct dsa_switch_tree *dst;
290 int i;
291
292 if (!dsa_version_printed++)
293 printk(KERN_NOTICE "Distributed Switch Architecture "
294 "driver version %s\n", dsa_driver_version);
295
296 if (pd == NULL || pd->netdev == NULL)
297 return -EINVAL;
298
299 dev = dev_to_net_device(pd->netdev);
300 if (dev == NULL)
301 return -EINVAL;
302
303 if (dev->dsa_ptr != NULL) {
304 dev_put(dev);
305 return -EEXIST;
306 }
307
308 dst = kzalloc(sizeof(*dst), GFP_KERNEL);
309 if (dst == NULL) {
310 dev_put(dev);
311 return -ENOMEM;
312 }
313
314 platform_set_drvdata(pdev, dst);
315
316 dst->pd = pd;
317 dst->master_netdev = dev;
318 dst->cpu_switch = -1;
319 dst->cpu_port = -1;
320
321 for (i = 0; i < pd->nr_chips; i++) {
322 struct mii_bus *bus;
323 struct dsa_switch *ds;
324
325 bus = dev_to_mii_bus(pd->chip[i].mii_bus);
326 if (bus == NULL) {
327 printk(KERN_ERR "%s[%d]: no mii bus found for "
328 "dsa switch\n", dev->name, i);
329 continue;
330 }
331
332 ds = dsa_switch_setup(dst, i, &pdev->dev, bus);
333 if (IS_ERR(ds)) {
334 printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
335 "instance (error %ld)\n", dev->name, i,
336 PTR_ERR(ds));
337 continue;
338 }
339
340 dst->ds[i] = ds;
341 if (ds->drv->poll_link != NULL)
342 dst->link_poll_needed = 1;
343 }
344
345 /*
346 * If we use a tagging format that doesn't have an ethertype
347 * field, make sure that all packets from this point on get
348 * sent to the tag format's receive function.
349 */
350 wmb();
351 dev->dsa_ptr = (void *)dst;
352
353 if (dst->link_poll_needed) {
354 INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
355 init_timer(&dst->link_poll_timer);
356 dst->link_poll_timer.data = (unsigned long)dst;
357 dst->link_poll_timer.function = dsa_link_poll_timer;
358 dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
359 add_timer(&dst->link_poll_timer);
360 }
361
362 return 0;
363 }
364
dsa_remove(struct platform_device * pdev)365 static int dsa_remove(struct platform_device *pdev)
366 {
367 struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
368 int i;
369
370 if (dst->link_poll_needed)
371 del_timer_sync(&dst->link_poll_timer);
372
373 flush_work_sync(&dst->link_poll_work);
374
375 for (i = 0; i < dst->pd->nr_chips; i++) {
376 struct dsa_switch *ds = dst->ds[i];
377
378 if (ds != NULL)
379 dsa_switch_destroy(ds);
380 }
381
382 return 0;
383 }
384
dsa_shutdown(struct platform_device * pdev)385 static void dsa_shutdown(struct platform_device *pdev)
386 {
387 }
388
389 static struct platform_driver dsa_driver = {
390 .probe = dsa_probe,
391 .remove = dsa_remove,
392 .shutdown = dsa_shutdown,
393 .driver = {
394 .name = "dsa",
395 .owner = THIS_MODULE,
396 },
397 };
398
dsa_init_module(void)399 static int __init dsa_init_module(void)
400 {
401 int rc;
402
403 rc = platform_driver_register(&dsa_driver);
404 if (rc)
405 return rc;
406
407 #ifdef CONFIG_NET_DSA_TAG_DSA
408 dev_add_pack(&dsa_packet_type);
409 #endif
410 #ifdef CONFIG_NET_DSA_TAG_EDSA
411 dev_add_pack(&edsa_packet_type);
412 #endif
413 #ifdef CONFIG_NET_DSA_TAG_TRAILER
414 dev_add_pack(&trailer_packet_type);
415 #endif
416 return 0;
417 }
418 module_init(dsa_init_module);
419
dsa_cleanup_module(void)420 static void __exit dsa_cleanup_module(void)
421 {
422 #ifdef CONFIG_NET_DSA_TAG_TRAILER
423 dev_remove_pack(&trailer_packet_type);
424 #endif
425 #ifdef CONFIG_NET_DSA_TAG_EDSA
426 dev_remove_pack(&edsa_packet_type);
427 #endif
428 #ifdef CONFIG_NET_DSA_TAG_DSA
429 dev_remove_pack(&dsa_packet_type);
430 #endif
431 platform_driver_unregister(&dsa_driver);
432 }
433 module_exit(dsa_cleanup_module);
434
435 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
436 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
437 MODULE_LICENSE("GPL");
438 MODULE_ALIAS("platform:dsa");
439