Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael...
[linux-2.6.git] / net / dsa / dsa.c
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
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
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 *
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 *
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
199 static void dsa_switch_destroy(struct dsa_switch *ds)
200 {
201 }
202
203
204 /* link polling *************************************************************/
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
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 *****************************************/
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
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
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
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
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
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
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
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
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");