1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2008 by Karsten Keil <kkeil@novell.com>
4 */
5
6 #include <linux/slab.h>
7 #include <linux/types.h>
8 #include <linux/stddef.h>
9 #include <linux/module.h>
10 #include <linux/spinlock.h>
11 #include <linux/mISDNif.h>
12 #include "core.h"
13
14 static u_int debug;
15
16 MODULE_AUTHOR("Karsten Keil");
17 MODULE_LICENSE("GPL");
18 module_param(debug, uint, S_IRUGO | S_IWUSR);
19
20 static u64 device_ids;
21 #define MAX_DEVICE_ID 63
22
23 static LIST_HEAD(Bprotocols);
24 static DEFINE_RWLOCK(bp_lock);
25
mISDN_dev_release(struct device * dev)26 static void mISDN_dev_release(struct device *dev)
27 {
28 /* nothing to do: the device is part of its parent's data structure */
29 }
30
id_show(struct device * dev,struct device_attribute * attr,char * buf)31 static ssize_t id_show(struct device *dev,
32 struct device_attribute *attr, char *buf)
33 {
34 struct mISDNdevice *mdev = dev_to_mISDN(dev);
35
36 if (!mdev)
37 return -ENODEV;
38 return sprintf(buf, "%d\n", mdev->id);
39 }
40 static DEVICE_ATTR_RO(id);
41
nrbchan_show(struct device * dev,struct device_attribute * attr,char * buf)42 static ssize_t nrbchan_show(struct device *dev,
43 struct device_attribute *attr, char *buf)
44 {
45 struct mISDNdevice *mdev = dev_to_mISDN(dev);
46
47 if (!mdev)
48 return -ENODEV;
49 return sprintf(buf, "%d\n", mdev->nrbchan);
50 }
51 static DEVICE_ATTR_RO(nrbchan);
52
d_protocols_show(struct device * dev,struct device_attribute * attr,char * buf)53 static ssize_t d_protocols_show(struct device *dev,
54 struct device_attribute *attr, char *buf)
55 {
56 struct mISDNdevice *mdev = dev_to_mISDN(dev);
57
58 if (!mdev)
59 return -ENODEV;
60 return sprintf(buf, "%d\n", mdev->Dprotocols);
61 }
62 static DEVICE_ATTR_RO(d_protocols);
63
b_protocols_show(struct device * dev,struct device_attribute * attr,char * buf)64 static ssize_t b_protocols_show(struct device *dev,
65 struct device_attribute *attr, char *buf)
66 {
67 struct mISDNdevice *mdev = dev_to_mISDN(dev);
68
69 if (!mdev)
70 return -ENODEV;
71 return sprintf(buf, "%d\n", mdev->Bprotocols | get_all_Bprotocols());
72 }
73 static DEVICE_ATTR_RO(b_protocols);
74
protocol_show(struct device * dev,struct device_attribute * attr,char * buf)75 static ssize_t protocol_show(struct device *dev,
76 struct device_attribute *attr, char *buf)
77 {
78 struct mISDNdevice *mdev = dev_to_mISDN(dev);
79
80 if (!mdev)
81 return -ENODEV;
82 return sprintf(buf, "%d\n", mdev->D.protocol);
83 }
84 static DEVICE_ATTR_RO(protocol);
85
name_show(struct device * dev,struct device_attribute * attr,char * buf)86 static ssize_t name_show(struct device *dev,
87 struct device_attribute *attr, char *buf)
88 {
89 strcpy(buf, dev_name(dev));
90 return strlen(buf);
91 }
92 static DEVICE_ATTR_RO(name);
93
94 #if 0 /* hangs */
95 static ssize_t name_set(struct device *dev, struct device_attribute *attr,
96 const char *buf, size_t count)
97 {
98 int err = 0;
99 char *out = kmalloc(count + 1, GFP_KERNEL);
100
101 if (!out)
102 return -ENOMEM;
103
104 memcpy(out, buf, count);
105 if (count && out[count - 1] == '\n')
106 out[--count] = 0;
107 if (count)
108 err = device_rename(dev, out);
109 kfree(out);
110
111 return (err < 0) ? err : count;
112 }
113 static DEVICE_ATTR_RW(name);
114 #endif
115
channelmap_show(struct device * dev,struct device_attribute * attr,char * buf)116 static ssize_t channelmap_show(struct device *dev,
117 struct device_attribute *attr, char *buf)
118 {
119 struct mISDNdevice *mdev = dev_to_mISDN(dev);
120 char *bp = buf;
121 int i;
122
123 for (i = 0; i <= mdev->nrbchan; i++)
124 *bp++ = test_channelmap(i, mdev->channelmap) ? '1' : '0';
125
126 return bp - buf;
127 }
128 static DEVICE_ATTR_RO(channelmap);
129
130 static struct attribute *mISDN_attrs[] = {
131 &dev_attr_id.attr,
132 &dev_attr_d_protocols.attr,
133 &dev_attr_b_protocols.attr,
134 &dev_attr_protocol.attr,
135 &dev_attr_channelmap.attr,
136 &dev_attr_nrbchan.attr,
137 &dev_attr_name.attr,
138 NULL,
139 };
140 ATTRIBUTE_GROUPS(mISDN);
141
mISDN_uevent(const struct device * dev,struct kobj_uevent_env * env)142 static int mISDN_uevent(const struct device *dev, struct kobj_uevent_env *env)
143 {
144 const struct mISDNdevice *mdev = dev_to_mISDN(dev);
145
146 if (!mdev)
147 return 0;
148
149 if (add_uevent_var(env, "nchans=%d", mdev->nrbchan))
150 return -ENOMEM;
151
152 return 0;
153 }
154
155 static struct class mISDN_class = {
156 .name = "mISDN",
157 .dev_uevent = mISDN_uevent,
158 .dev_groups = mISDN_groups,
159 .dev_release = mISDN_dev_release,
160 };
161
162 static int
_get_mdevice(struct device * dev,const void * id)163 _get_mdevice(struct device *dev, const void *id)
164 {
165 struct mISDNdevice *mdev = dev_to_mISDN(dev);
166
167 if (!mdev)
168 return 0;
169 if (mdev->id != *(const u_int *)id)
170 return 0;
171 return 1;
172 }
173
174 struct mISDNdevice
get_mdevice(u_int id)175 *get_mdevice(u_int id)
176 {
177 return dev_to_mISDN(class_find_device(&mISDN_class, NULL, &id,
178 _get_mdevice));
179 }
180
181 static int
_get_mdevice_count(struct device * dev,void * cnt)182 _get_mdevice_count(struct device *dev, void *cnt)
183 {
184 *(int *)cnt += 1;
185 return 0;
186 }
187
188 int
get_mdevice_count(void)189 get_mdevice_count(void)
190 {
191 int cnt = 0;
192
193 class_for_each_device(&mISDN_class, NULL, &cnt, _get_mdevice_count);
194 return cnt;
195 }
196
197 static int
get_free_devid(void)198 get_free_devid(void)
199 {
200 u_int i;
201
202 for (i = 0; i <= MAX_DEVICE_ID; i++)
203 if (!test_and_set_bit(i, (u_long *)&device_ids))
204 break;
205 if (i > MAX_DEVICE_ID)
206 return -EBUSY;
207 return i;
208 }
209
210 int
mISDN_register_device(struct mISDNdevice * dev,struct device * parent,char * name)211 mISDN_register_device(struct mISDNdevice *dev,
212 struct device *parent, char *name)
213 {
214 int err;
215
216 err = get_free_devid();
217 if (err < 0)
218 return err;
219 dev->id = err;
220
221 device_initialize(&dev->dev);
222 if (name && name[0])
223 dev_set_name(&dev->dev, "%s", name);
224 else
225 dev_set_name(&dev->dev, "mISDN%d", dev->id);
226 if (debug & DEBUG_CORE)
227 printk(KERN_DEBUG "mISDN_register %s %d\n",
228 dev_name(&dev->dev), dev->id);
229 dev->dev.class = &mISDN_class;
230
231 err = create_stack(dev);
232 if (err)
233 goto error1;
234
235 dev->dev.platform_data = dev;
236 dev->dev.parent = parent;
237 dev_set_drvdata(&dev->dev, dev);
238
239 err = device_add(&dev->dev);
240 if (err)
241 goto error3;
242 return 0;
243
244 error3:
245 delete_stack(dev);
246 error1:
247 put_device(&dev->dev);
248 return err;
249
250 }
251 EXPORT_SYMBOL(mISDN_register_device);
252
253 void
mISDN_unregister_device(struct mISDNdevice * dev)254 mISDN_unregister_device(struct mISDNdevice *dev) {
255 if (debug & DEBUG_CORE)
256 printk(KERN_DEBUG "mISDN_unregister %s %d\n",
257 dev_name(&dev->dev), dev->id);
258 /* sysfs_remove_link(&dev->dev.kobj, "device"); */
259 device_del(&dev->dev);
260 dev_set_drvdata(&dev->dev, NULL);
261
262 test_and_clear_bit(dev->id, (u_long *)&device_ids);
263 delete_stack(dev);
264 put_device(&dev->dev);
265 }
266 EXPORT_SYMBOL(mISDN_unregister_device);
267
268 u_int
get_all_Bprotocols(void)269 get_all_Bprotocols(void)
270 {
271 struct Bprotocol *bp;
272 u_int m = 0;
273
274 read_lock(&bp_lock);
275 list_for_each_entry(bp, &Bprotocols, list)
276 m |= bp->Bprotocols;
277 read_unlock(&bp_lock);
278 return m;
279 }
280
281 struct Bprotocol *
get_Bprotocol4mask(u_int m)282 get_Bprotocol4mask(u_int m)
283 {
284 struct Bprotocol *bp;
285
286 read_lock(&bp_lock);
287 list_for_each_entry(bp, &Bprotocols, list)
288 if (bp->Bprotocols & m) {
289 read_unlock(&bp_lock);
290 return bp;
291 }
292 read_unlock(&bp_lock);
293 return NULL;
294 }
295
296 struct Bprotocol *
get_Bprotocol4id(u_int id)297 get_Bprotocol4id(u_int id)
298 {
299 u_int m;
300
301 if (id < ISDN_P_B_START || id > 63) {
302 printk(KERN_WARNING "%s id not in range %d\n",
303 __func__, id);
304 return NULL;
305 }
306 m = 1 << (id & ISDN_P_B_MASK);
307 return get_Bprotocol4mask(m);
308 }
309
310 int
mISDN_register_Bprotocol(struct Bprotocol * bp)311 mISDN_register_Bprotocol(struct Bprotocol *bp)
312 {
313 u_long flags;
314 struct Bprotocol *old;
315
316 if (debug & DEBUG_CORE)
317 printk(KERN_DEBUG "%s: %s/%x\n", __func__,
318 bp->name, bp->Bprotocols);
319 old = get_Bprotocol4mask(bp->Bprotocols);
320 if (old) {
321 printk(KERN_WARNING
322 "register duplicate protocol old %s/%x new %s/%x\n",
323 old->name, old->Bprotocols, bp->name, bp->Bprotocols);
324 return -EBUSY;
325 }
326 write_lock_irqsave(&bp_lock, flags);
327 list_add_tail(&bp->list, &Bprotocols);
328 write_unlock_irqrestore(&bp_lock, flags);
329 return 0;
330 }
331 EXPORT_SYMBOL(mISDN_register_Bprotocol);
332
333 void
mISDN_unregister_Bprotocol(struct Bprotocol * bp)334 mISDN_unregister_Bprotocol(struct Bprotocol *bp)
335 {
336 u_long flags;
337
338 if (debug & DEBUG_CORE)
339 printk(KERN_DEBUG "%s: %s/%x\n", __func__, bp->name,
340 bp->Bprotocols);
341 write_lock_irqsave(&bp_lock, flags);
342 list_del(&bp->list);
343 write_unlock_irqrestore(&bp_lock, flags);
344 }
345 EXPORT_SYMBOL(mISDN_unregister_Bprotocol);
346
347 static const char *msg_no_channel = "<no channel>";
348 static const char *msg_no_stack = "<no stack>";
349 static const char *msg_no_stackdev = "<no stack device>";
350
mISDNDevName4ch(struct mISDNchannel * ch)351 const char *mISDNDevName4ch(struct mISDNchannel *ch)
352 {
353 if (!ch)
354 return msg_no_channel;
355 if (!ch->st)
356 return msg_no_stack;
357 if (!ch->st->dev)
358 return msg_no_stackdev;
359 return dev_name(&ch->st->dev->dev);
360 };
361 EXPORT_SYMBOL(mISDNDevName4ch);
362
363 static int
mISDNInit(void)364 mISDNInit(void)
365 {
366 int err;
367
368 printk(KERN_INFO "Modular ISDN core version %d.%d.%d\n",
369 MISDN_MAJOR_VERSION, MISDN_MINOR_VERSION, MISDN_RELEASE);
370 mISDN_init_clock(&debug);
371 mISDN_initstack(&debug);
372 err = class_register(&mISDN_class);
373 if (err)
374 goto error1;
375 err = mISDN_inittimer(&debug);
376 if (err)
377 goto error2;
378 err = Isdnl1_Init(&debug);
379 if (err)
380 goto error3;
381 err = Isdnl2_Init(&debug);
382 if (err)
383 goto error4;
384 err = misdn_sock_init(&debug);
385 if (err)
386 goto error5;
387 return 0;
388
389 error5:
390 Isdnl2_cleanup();
391 error4:
392 Isdnl1_cleanup();
393 error3:
394 mISDN_timer_cleanup();
395 error2:
396 class_unregister(&mISDN_class);
397 error1:
398 return err;
399 }
400
mISDN_cleanup(void)401 static void mISDN_cleanup(void)
402 {
403 misdn_sock_cleanup();
404 Isdnl2_cleanup();
405 Isdnl1_cleanup();
406 mISDN_timer_cleanup();
407 class_unregister(&mISDN_class);
408
409 printk(KERN_DEBUG "mISDNcore unloaded\n");
410 }
411
412 module_init(mISDNInit);
413 module_exit(mISDN_cleanup);
414