net: struct device - replace bus_id with dev_name(), dev_set_name()
[linux-2.6.git] / net / dsa / dsa.c
1 /*
2  * net/dsa/dsa.c - Hardware switch handling
3  * Copyright (c) 2008 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 <net/dsa.h>
15 #include "dsa_priv.h"
16
17 char dsa_driver_version[] = "0.1";
18
19
20 /* switch driver registration ***********************************************/
21 static DEFINE_MUTEX(dsa_switch_drivers_mutex);
22 static LIST_HEAD(dsa_switch_drivers);
23
24 void register_switch_driver(struct dsa_switch_driver *drv)
25 {
26         mutex_lock(&dsa_switch_drivers_mutex);
27         list_add_tail(&drv->list, &dsa_switch_drivers);
28         mutex_unlock(&dsa_switch_drivers_mutex);
29 }
30
31 void unregister_switch_driver(struct dsa_switch_driver *drv)
32 {
33         mutex_lock(&dsa_switch_drivers_mutex);
34         list_del_init(&drv->list);
35         mutex_unlock(&dsa_switch_drivers_mutex);
36 }
37
38 static struct dsa_switch_driver *
39 dsa_switch_probe(struct mii_bus *bus, int sw_addr, char **_name)
40 {
41         struct dsa_switch_driver *ret;
42         struct list_head *list;
43         char *name;
44
45         ret = NULL;
46         name = NULL;
47
48         mutex_lock(&dsa_switch_drivers_mutex);
49         list_for_each(list, &dsa_switch_drivers) {
50                 struct dsa_switch_driver *drv;
51
52                 drv = list_entry(list, struct dsa_switch_driver, list);
53
54                 name = drv->probe(bus, sw_addr);
55                 if (name != NULL) {
56                         ret = drv;
57                         break;
58                 }
59         }
60         mutex_unlock(&dsa_switch_drivers_mutex);
61
62         *_name = name;
63
64         return ret;
65 }
66
67
68 /* basic switch operations **************************************************/
69 static struct dsa_switch *
70 dsa_switch_setup(struct device *parent, struct dsa_platform_data *pd,
71                  struct mii_bus *bus, struct net_device *dev)
72 {
73         struct dsa_switch *ds;
74         int ret;
75         struct dsa_switch_driver *drv;
76         char *name;
77         int i;
78
79         /*
80          * Probe for switch model.
81          */
82         drv = dsa_switch_probe(bus, pd->sw_addr, &name);
83         if (drv == NULL) {
84                 printk(KERN_ERR "%s: could not detect attached switch\n",
85                        dev->name);
86                 return ERR_PTR(-EINVAL);
87         }
88         printk(KERN_INFO "%s: detected a %s switch\n", dev->name, name);
89
90
91         /*
92          * Allocate and initialise switch state.
93          */
94         ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
95         if (ds == NULL)
96                 return ERR_PTR(-ENOMEM);
97
98         ds->pd = pd;
99         ds->master_netdev = dev;
100         ds->master_mii_bus = bus;
101
102         ds->drv = drv;
103         ds->tag_protocol = drv->tag_protocol;
104
105
106         /*
107          * Validate supplied switch configuration.
108          */
109         ds->cpu_port = -1;
110         for (i = 0; i < DSA_MAX_PORTS; i++) {
111                 char *name;
112
113                 name = pd->port_names[i];
114                 if (name == NULL)
115                         continue;
116
117                 if (!strcmp(name, "cpu")) {
118                         if (ds->cpu_port != -1) {
119                                 printk(KERN_ERR "multiple cpu ports?!\n");
120                                 ret = -EINVAL;
121                                 goto out;
122                         }
123                         ds->cpu_port = i;
124                 } else {
125                         ds->valid_port_mask |= 1 << i;
126                 }
127         }
128
129         if (ds->cpu_port == -1) {
130                 printk(KERN_ERR "no cpu port?!\n");
131                 ret = -EINVAL;
132                 goto out;
133         }
134
135
136         /*
137          * If we use a tagging format that doesn't have an ethertype
138          * field, make sure that all packets from this point on get
139          * sent to the tag format's receive function.  (Which will
140          * discard received packets until we set ds->ports[] below.)
141          */
142         wmb();
143         dev->dsa_ptr = (void *)ds;
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, dev->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         wmb();
173         for (i = 0; i < DSA_MAX_PORTS; i++) {
174                 struct net_device *slave_dev;
175
176                 if (!(ds->valid_port_mask & (1 << i)))
177                         continue;
178
179                 slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
180                 if (slave_dev == NULL) {
181                         printk(KERN_ERR "%s: can't create dsa slave "
182                                "device for port %d(%s)\n",
183                                dev->name, 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         dev->dsa_ptr = NULL;
196         kfree(ds);
197         return ERR_PTR(ret);
198 }
199
200 static void dsa_switch_destroy(struct dsa_switch *ds)
201 {
202 }
203
204
205 /* hooks for ethertype-less tagging formats *********************************/
206 /*
207  * The original DSA tag format and some other tag formats have no
208  * ethertype, which means that we need to add a little hack to the
209  * networking receive path to make sure that received frames get
210  * the right ->protocol assigned to them when one of those tag
211  * formats is in use.
212  */
213 bool dsa_uses_dsa_tags(void *dsa_ptr)
214 {
215         struct dsa_switch *ds = dsa_ptr;
216
217         return !!(ds->tag_protocol == htons(ETH_P_DSA));
218 }
219
220 bool dsa_uses_trailer_tags(void *dsa_ptr)
221 {
222         struct dsa_switch *ds = dsa_ptr;
223
224         return !!(ds->tag_protocol == htons(ETH_P_TRAILER));
225 }
226
227
228 /* link polling *************************************************************/
229 static void dsa_link_poll_work(struct work_struct *ugly)
230 {
231         struct dsa_switch *ds;
232
233         ds = container_of(ugly, struct dsa_switch, link_poll_work);
234
235         ds->drv->poll_link(ds);
236         mod_timer(&ds->link_poll_timer, round_jiffies(jiffies + HZ));
237 }
238
239 static void dsa_link_poll_timer(unsigned long _ds)
240 {
241         struct dsa_switch *ds = (void *)_ds;
242
243         schedule_work(&ds->link_poll_work);
244 }
245
246
247 /* platform driver init and cleanup *****************************************/
248 static int dev_is_class(struct device *dev, void *class)
249 {
250         if (dev->class != NULL && !strcmp(dev->class->name, class))
251                 return 1;
252
253         return 0;
254 }
255
256 static struct device *dev_find_class(struct device *parent, char *class)
257 {
258         if (dev_is_class(parent, class)) {
259                 get_device(parent);
260                 return parent;
261         }
262
263         return device_find_child(parent, class, dev_is_class);
264 }
265
266 static struct mii_bus *dev_to_mii_bus(struct device *dev)
267 {
268         struct device *d;
269
270         d = dev_find_class(dev, "mdio_bus");
271         if (d != NULL) {
272                 struct mii_bus *bus;
273
274                 bus = to_mii_bus(d);
275                 put_device(d);
276
277                 return bus;
278         }
279
280         return NULL;
281 }
282
283 static struct net_device *dev_to_net_device(struct device *dev)
284 {
285         struct device *d;
286
287         d = dev_find_class(dev, "net");
288         if (d != NULL) {
289                 struct net_device *nd;
290
291                 nd = to_net_dev(d);
292                 dev_hold(nd);
293                 put_device(d);
294
295                 return nd;
296         }
297
298         return NULL;
299 }
300
301 static int dsa_probe(struct platform_device *pdev)
302 {
303         static int dsa_version_printed;
304         struct dsa_platform_data *pd = pdev->dev.platform_data;
305         struct net_device *dev;
306         struct mii_bus *bus;
307         struct dsa_switch *ds;
308
309         if (!dsa_version_printed++)
310                 printk(KERN_NOTICE "Distributed Switch Architecture "
311                         "driver version %s\n", dsa_driver_version);
312
313         if (pd == NULL || pd->mii_bus == NULL || pd->netdev == NULL)
314                 return -EINVAL;
315
316         bus = dev_to_mii_bus(pd->mii_bus);
317         if (bus == NULL)
318                 return -EINVAL;
319
320         dev = dev_to_net_device(pd->netdev);
321         if (dev == NULL)
322                 return -EINVAL;
323
324         if (dev->dsa_ptr != NULL) {
325                 dev_put(dev);
326                 return -EEXIST;
327         }
328
329         ds = dsa_switch_setup(&pdev->dev, pd, bus, dev);
330         if (IS_ERR(ds)) {
331                 dev_put(dev);
332                 return PTR_ERR(ds);
333         }
334
335         if (ds->drv->poll_link != NULL) {
336                 INIT_WORK(&ds->link_poll_work, dsa_link_poll_work);
337                 init_timer(&ds->link_poll_timer);
338                 ds->link_poll_timer.data = (unsigned long)ds;
339                 ds->link_poll_timer.function = dsa_link_poll_timer;
340                 ds->link_poll_timer.expires = round_jiffies(jiffies + HZ);
341                 add_timer(&ds->link_poll_timer);
342         }
343
344         platform_set_drvdata(pdev, ds);
345
346         return 0;
347 }
348
349 static int dsa_remove(struct platform_device *pdev)
350 {
351         struct dsa_switch *ds = platform_get_drvdata(pdev);
352
353         if (ds->drv->poll_link != NULL)
354                 del_timer_sync(&ds->link_poll_timer);
355
356         flush_scheduled_work();
357
358         dsa_switch_destroy(ds);
359
360         return 0;
361 }
362
363 static void dsa_shutdown(struct platform_device *pdev)
364 {
365 }
366
367 static struct platform_driver dsa_driver = {
368         .probe          = dsa_probe,
369         .remove         = dsa_remove,
370         .shutdown       = dsa_shutdown,
371         .driver = {
372                 .name   = "dsa",
373                 .owner  = THIS_MODULE,
374         },
375 };
376
377 static int __init dsa_init_module(void)
378 {
379         return platform_driver_register(&dsa_driver);
380 }
381 module_init(dsa_init_module);
382
383 static void __exit dsa_cleanup_module(void)
384 {
385         platform_driver_unregister(&dsa_driver);
386 }
387 module_exit(dsa_cleanup_module);
388
389 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>")
390 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
391 MODULE_LICENSE("GPL");
392 MODULE_ALIAS("platform:dsa");