xref: /openbmc/linux/drivers/isdn/mISDN/core.c (revision 2223cbec)
1 /*
2  * Copyright 2008  by Karsten Keil <kkeil@novell.com>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  */
14 
15 #include <linux/slab.h>
16 #include <linux/types.h>
17 #include <linux/stddef.h>
18 #include <linux/module.h>
19 #include <linux/spinlock.h>
20 #include <linux/mISDNif.h>
21 #include "core.h"
22 
23 static u_int debug;
24 
25 MODULE_AUTHOR("Karsten Keil");
26 MODULE_LICENSE("GPL");
27 module_param(debug, uint, S_IRUGO | S_IWUSR);
28 
29 static u64		device_ids;
30 #define MAX_DEVICE_ID	63
31 
32 static LIST_HEAD(Bprotocols);
33 static DEFINE_RWLOCK(bp_lock);
34 
35 static void mISDN_dev_release(struct device *dev)
36 {
37 	/* nothing to do: the device is part of its parent's data structure */
38 }
39 
40 static ssize_t _show_id(struct device *dev,
41 			struct device_attribute *attr, char *buf)
42 {
43 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
44 
45 	if (!mdev)
46 		return -ENODEV;
47 	return sprintf(buf, "%d\n", mdev->id);
48 }
49 
50 static ssize_t _show_nrbchan(struct device *dev,
51 			     struct device_attribute *attr, char *buf)
52 {
53 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
54 
55 	if (!mdev)
56 		return -ENODEV;
57 	return sprintf(buf, "%d\n", mdev->nrbchan);
58 }
59 
60 static ssize_t _show_d_protocols(struct device *dev,
61 				 struct device_attribute *attr, char *buf)
62 {
63 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
64 
65 	if (!mdev)
66 		return -ENODEV;
67 	return sprintf(buf, "%d\n", mdev->Dprotocols);
68 }
69 
70 static ssize_t _show_b_protocols(struct device *dev,
71 				 struct device_attribute *attr, char *buf)
72 {
73 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
74 
75 	if (!mdev)
76 		return -ENODEV;
77 	return sprintf(buf, "%d\n", mdev->Bprotocols | get_all_Bprotocols());
78 }
79 
80 static ssize_t _show_protocol(struct device *dev,
81 			      struct device_attribute *attr, char *buf)
82 {
83 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
84 
85 	if (!mdev)
86 		return -ENODEV;
87 	return sprintf(buf, "%d\n", mdev->D.protocol);
88 }
89 
90 static ssize_t _show_name(struct device *dev,
91 			  struct device_attribute *attr, char *buf)
92 {
93 	strcpy(buf, dev_name(dev));
94 	return strlen(buf);
95 }
96 
97 #if 0 /* hangs */
98 static ssize_t _set_name(struct device *dev, struct device_attribute *attr,
99 			 const char *buf, size_t count)
100 {
101 	int err = 0;
102 	char *out = kmalloc(count + 1, GFP_KERNEL);
103 
104 	if (!out)
105 		return -ENOMEM;
106 
107 	memcpy(out, buf, count);
108 	if (count && out[count - 1] == '\n')
109 		out[--count] = 0;
110 	if (count)
111 		err = device_rename(dev, out);
112 	kfree(out);
113 
114 	return (err < 0) ? err : count;
115 }
116 #endif
117 
118 static ssize_t _show_channelmap(struct device *dev,
119 				struct device_attribute *attr, char *buf)
120 {
121 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
122 	char *bp = buf;
123 	int i;
124 
125 	for (i = 0; i <= mdev->nrbchan; i++)
126 		*bp++ = test_channelmap(i, mdev->channelmap) ? '1' : '0';
127 
128 	return bp - buf;
129 }
130 
131 static struct device_attribute mISDN_dev_attrs[] = {
132 	__ATTR(id,          S_IRUGO,         _show_id,          NULL),
133 	__ATTR(d_protocols, S_IRUGO,         _show_d_protocols, NULL),
134 	__ATTR(b_protocols, S_IRUGO,         _show_b_protocols, NULL),
135 	__ATTR(protocol,    S_IRUGO,         _show_protocol,    NULL),
136 	__ATTR(channelmap,  S_IRUGO,         _show_channelmap,  NULL),
137 	__ATTR(nrbchan,     S_IRUGO,         _show_nrbchan,     NULL),
138 	__ATTR(name,        S_IRUGO,         _show_name,        NULL),
139 /*	__ATTR(name,        S_IRUGO | S_IWUSR, _show_name,      _set_name), */
140 	{}
141 };
142 
143 #ifdef CONFIG_HOTPLUG
144 static int mISDN_uevent(struct device *dev, struct kobj_uevent_env *env)
145 {
146 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
147 
148 	if (!mdev)
149 		return 0;
150 
151 	if (add_uevent_var(env, "nchans=%d", mdev->nrbchan))
152 		return -ENOMEM;
153 
154 	return 0;
155 }
156 #endif
157 
158 static void mISDN_class_release(struct class *cls)
159 {
160 	/* do nothing, it's static */
161 }
162 
163 static struct class mISDN_class = {
164 	.name = "mISDN",
165 	.owner = THIS_MODULE,
166 #ifdef CONFIG_HOTPLUG
167 	.dev_uevent = mISDN_uevent,
168 #endif
169 	.dev_attrs = mISDN_dev_attrs,
170 	.dev_release = mISDN_dev_release,
171 	.class_release = mISDN_class_release,
172 };
173 
174 static int
175 _get_mdevice(struct device *dev, void *id)
176 {
177 	struct mISDNdevice *mdev = dev_to_mISDN(dev);
178 
179 	if (!mdev)
180 		return 0;
181 	if (mdev->id != *(u_int *)id)
182 		return 0;
183 	return 1;
184 }
185 
186 struct mISDNdevice
187 *get_mdevice(u_int id)
188 {
189 	return dev_to_mISDN(class_find_device(&mISDN_class, NULL, &id,
190 					      _get_mdevice));
191 }
192 
193 static int
194 _get_mdevice_count(struct device *dev, void *cnt)
195 {
196 	*(int *)cnt += 1;
197 	return 0;
198 }
199 
200 int
201 get_mdevice_count(void)
202 {
203 	int cnt = 0;
204 
205 	class_for_each_device(&mISDN_class, NULL, &cnt, _get_mdevice_count);
206 	return cnt;
207 }
208 
209 static int
210 get_free_devid(void)
211 {
212 	u_int	i;
213 
214 	for (i = 0; i <= MAX_DEVICE_ID; i++)
215 		if (!test_and_set_bit(i, (u_long *)&device_ids))
216 			break;
217 	if (i > MAX_DEVICE_ID)
218 		return -EBUSY;
219 	return i;
220 }
221 
222 int
223 mISDN_register_device(struct mISDNdevice *dev,
224 		      struct device *parent, char *name)
225 {
226 	int	err;
227 
228 	err = get_free_devid();
229 	if (err < 0)
230 		goto error1;
231 	dev->id = err;
232 
233 	device_initialize(&dev->dev);
234 	if (name && name[0])
235 		dev_set_name(&dev->dev, "%s", name);
236 	else
237 		dev_set_name(&dev->dev, "mISDN%d", dev->id);
238 	if (debug & DEBUG_CORE)
239 		printk(KERN_DEBUG "mISDN_register %s %d\n",
240 		       dev_name(&dev->dev), dev->id);
241 	err = create_stack(dev);
242 	if (err)
243 		goto error1;
244 
245 	dev->dev.class = &mISDN_class;
246 	dev->dev.platform_data = dev;
247 	dev->dev.parent = parent;
248 	dev_set_drvdata(&dev->dev, dev);
249 
250 	err = device_add(&dev->dev);
251 	if (err)
252 		goto error3;
253 	return 0;
254 
255 error3:
256 	delete_stack(dev);
257 	return err;
258 error1:
259 	return err;
260 
261 }
262 EXPORT_SYMBOL(mISDN_register_device);
263 
264 void
265 mISDN_unregister_device(struct mISDNdevice *dev) {
266 	if (debug & DEBUG_CORE)
267 		printk(KERN_DEBUG "mISDN_unregister %s %d\n",
268 		       dev_name(&dev->dev), dev->id);
269 	/* sysfs_remove_link(&dev->dev.kobj, "device"); */
270 	device_del(&dev->dev);
271 	dev_set_drvdata(&dev->dev, NULL);
272 
273 	test_and_clear_bit(dev->id, (u_long *)&device_ids);
274 	delete_stack(dev);
275 	put_device(&dev->dev);
276 }
277 EXPORT_SYMBOL(mISDN_unregister_device);
278 
279 u_int
280 get_all_Bprotocols(void)
281 {
282 	struct Bprotocol	*bp;
283 	u_int	m = 0;
284 
285 	read_lock(&bp_lock);
286 	list_for_each_entry(bp, &Bprotocols, list)
287 		m |= bp->Bprotocols;
288 	read_unlock(&bp_lock);
289 	return m;
290 }
291 
292 struct Bprotocol *
293 get_Bprotocol4mask(u_int m)
294 {
295 	struct Bprotocol	*bp;
296 
297 	read_lock(&bp_lock);
298 	list_for_each_entry(bp, &Bprotocols, list)
299 		if (bp->Bprotocols & m) {
300 			read_unlock(&bp_lock);
301 			return bp;
302 		}
303 	read_unlock(&bp_lock);
304 	return NULL;
305 }
306 
307 struct Bprotocol *
308 get_Bprotocol4id(u_int id)
309 {
310 	u_int	m;
311 
312 	if (id < ISDN_P_B_START || id > 63) {
313 		printk(KERN_WARNING "%s id not in range  %d\n",
314 		       __func__, id);
315 		return NULL;
316 	}
317 	m = 1 << (id & ISDN_P_B_MASK);
318 	return get_Bprotocol4mask(m);
319 }
320 
321 int
322 mISDN_register_Bprotocol(struct Bprotocol *bp)
323 {
324 	u_long			flags;
325 	struct Bprotocol	*old;
326 
327 	if (debug & DEBUG_CORE)
328 		printk(KERN_DEBUG "%s: %s/%x\n", __func__,
329 		       bp->name, bp->Bprotocols);
330 	old = get_Bprotocol4mask(bp->Bprotocols);
331 	if (old) {
332 		printk(KERN_WARNING
333 		       "register duplicate protocol old %s/%x new %s/%x\n",
334 		       old->name, old->Bprotocols, bp->name, bp->Bprotocols);
335 		return -EBUSY;
336 	}
337 	write_lock_irqsave(&bp_lock, flags);
338 	list_add_tail(&bp->list, &Bprotocols);
339 	write_unlock_irqrestore(&bp_lock, flags);
340 	return 0;
341 }
342 EXPORT_SYMBOL(mISDN_register_Bprotocol);
343 
344 void
345 mISDN_unregister_Bprotocol(struct Bprotocol *bp)
346 {
347 	u_long	flags;
348 
349 	if (debug & DEBUG_CORE)
350 		printk(KERN_DEBUG "%s: %s/%x\n", __func__, bp->name,
351 		       bp->Bprotocols);
352 	write_lock_irqsave(&bp_lock, flags);
353 	list_del(&bp->list);
354 	write_unlock_irqrestore(&bp_lock, flags);
355 }
356 EXPORT_SYMBOL(mISDN_unregister_Bprotocol);
357 
358 static const char *msg_no_channel = "<no channel>";
359 static const char *msg_no_stack = "<no stack>";
360 static const char *msg_no_stackdev = "<no stack device>";
361 
362 const char *mISDNDevName4ch(struct mISDNchannel *ch)
363 {
364 	if (!ch)
365 		return msg_no_channel;
366 	if (!ch->st)
367 		return msg_no_stack;
368 	if (!ch->st->dev)
369 		return msg_no_stackdev;
370 	return dev_name(&ch->st->dev->dev);
371 };
372 EXPORT_SYMBOL(mISDNDevName4ch);
373 
374 static int
375 mISDNInit(void)
376 {
377 	int	err;
378 
379 	printk(KERN_INFO "Modular ISDN core version %d.%d.%d\n",
380 	       MISDN_MAJOR_VERSION, MISDN_MINOR_VERSION, MISDN_RELEASE);
381 	mISDN_init_clock(&debug);
382 	mISDN_initstack(&debug);
383 	err = class_register(&mISDN_class);
384 	if (err)
385 		goto error1;
386 	err = mISDN_inittimer(&debug);
387 	if (err)
388 		goto error2;
389 	err = l1_init(&debug);
390 	if (err)
391 		goto error3;
392 	err = Isdnl2_Init(&debug);
393 	if (err)
394 		goto error4;
395 	err = misdn_sock_init(&debug);
396 	if (err)
397 		goto error5;
398 	return 0;
399 
400 error5:
401 	Isdnl2_cleanup();
402 error4:
403 	l1_cleanup();
404 error3:
405 	mISDN_timer_cleanup();
406 error2:
407 	class_unregister(&mISDN_class);
408 error1:
409 	return err;
410 }
411 
412 static void mISDN_cleanup(void)
413 {
414 	misdn_sock_cleanup();
415 	Isdnl2_cleanup();
416 	l1_cleanup();
417 	mISDN_timer_cleanup();
418 	class_unregister(&mISDN_class);
419 
420 	printk(KERN_DEBUG "mISDNcore unloaded\n");
421 }
422 
423 module_init(mISDNInit);
424 module_exit(mISDN_cleanup);
425