drivers/isdn/mISDN/core.c

   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 id_show(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 static DEVICE_ATTR_RO(id);
  50
  51 static ssize_t nrbchan_show(struct device *dev,
  52                             struct device_attribute *attr, char *buf)
  53 {
  54         struct mISDNdevice *mdev = dev_to_mISDN(dev);
  55
  56         if (!mdev)
  57                 return -ENODEV;
  58         return sprintf(buf, "%d\n", mdev->nrbchan);
  59 }
  60 static DEVICE_ATTR_RO(nrbchan);
  61
  62 static ssize_t d_protocols_show(struct device *dev,
  63                                 struct device_attribute *attr, char *buf)
  64 {
  65         struct mISDNdevice *mdev = dev_to_mISDN(dev);
  66
  67         if (!mdev)
  68                 return -ENODEV;
  69         return sprintf(buf, "%d\n", mdev->Dprotocols);
  70 }
  71 static DEVICE_ATTR_RO(d_protocols);
  72
  73 static ssize_t b_protocols_show(struct device *dev,
  74                                 struct device_attribute *attr, char *buf)
  75 {
  76         struct mISDNdevice *mdev = dev_to_mISDN(dev);
  77
  78         if (!mdev)
  79                 return -ENODEV;
  80         return sprintf(buf, "%d\n", mdev->Bprotocols | get_all_Bprotocols());
  81 }
  82 static DEVICE_ATTR_RO(b_protocols);
  83
  84 static ssize_t protocol_show(struct device *dev,
  85                              struct device_attribute *attr, char *buf)
  86 {
  87         struct mISDNdevice *mdev = dev_to_mISDN(dev);
  88
  89         if (!mdev)
  90                 return -ENODEV;
  91         return sprintf(buf, "%d\n", mdev->D.protocol);
  92 }
  93 static DEVICE_ATTR_RO(protocol);
  94
  95 static ssize_t name_show(struct device *dev,
  96                          struct device_attribute *attr, char *buf)
  97 {
  98         strcpy(buf, dev_name(dev));
  99         return strlen(buf);
 100 }
 101 static DEVICE_ATTR_RO(name);
 102
 103 #if 0 /* hangs */
 104 static ssize_t name_set(struct device *dev, struct device_attribute *attr,
 105                         const char *buf, size_t count)
 106 {
 107         int err = 0;
 108         char *out = kmalloc(count + 1, GFP_KERNEL);
 109
 110         if (!out)
 111                 return -ENOMEM;
 112
 113         memcpy(out, buf, count);
 114         if (count && out[count - 1] == '\n')
 115                 out[--count] = 0;
 116         if (count)
 117                 err = device_rename(dev, out);
 118         kfree(out);
 119
 120         return (err < 0) ? err : count;
 121 }
 122 static DEVICE_ATTR_RW(name);
 123 #endif
 124
 125 static ssize_t channelmap_show(struct device *dev,
 126                                struct device_attribute *attr, char *buf)
 127 {
 128         struct mISDNdevice *mdev = dev_to_mISDN(dev);
 129         char *bp = buf;
 130         int i;
 131
 132         for (i = 0; i <= mdev->nrbchan; i++)
 133                 *bp++ = test_channelmap(i, mdev->channelmap) ? '1' : '0';
 134
 135         return bp - buf;
 136 }
 137 static DEVICE_ATTR_RO(channelmap);
 138
 139 static struct attribute *mISDN_attrs[] = {
 140         &dev_attr_id.attr,
 141         &dev_attr_d_protocols.attr,
 142         &dev_attr_b_protocols.attr,
 143         &dev_attr_protocol.attr,
 144         &dev_attr_channelmap.attr,
 145         &dev_attr_nrbchan.attr,
 146         &dev_attr_name.attr,
 147         NULL,
 148 };
 149 ATTRIBUTE_GROUPS(mISDN);
 150
 151 static int mISDN_uevent(struct device *dev, struct kobj_uevent_env *env)
 152 {
 153         struct mISDNdevice *mdev = dev_to_mISDN(dev);
 154
 155         if (!mdev)
 156                 return 0;
 157
 158         if (add_uevent_var(env, "nchans=%d", mdev->nrbchan))
 159                 return -ENOMEM;
 160
 161         return 0;
 162 }
 163
 164 static void mISDN_class_release(struct class *cls)
 165 {
 166         /* do nothing, it's static */
 167 }
 168
 169 static struct class mISDN_class = {
 170         .name = "mISDN",
 171         .owner = THIS_MODULE,
 172         .dev_uevent = mISDN_uevent,
 173         .dev_groups = mISDN_groups,
 174         .dev_release = mISDN_dev_release,
 175         .class_release = mISDN_class_release,
 176 };
 177
 178 static int
 179 _get_mdevice(struct device *dev, const void *id)
 180 {
 181         struct mISDNdevice *mdev = dev_to_mISDN(dev);
 182
 183         if (!mdev)
 184                 return 0;
 185         if (mdev->id != *(const u_int *)id)
 186                 return 0;
 187         return 1;
 188 }
 189
 190 struct mISDNdevice
 191 *get_mdevice(u_int id)
 192 {
 193         return dev_to_mISDN(class_find_device(&mISDN_class, NULL, &id,
 194                                               _get_mdevice));
 195 }
 196
 197 static int
 198 _get_mdevice_count(struct device *dev, void *cnt)
 199 {
 200         *(int *)cnt += 1;
 201         return 0;
 202 }
 203
 204 int
 205 get_mdevice_count(void)
 206 {
 207         int cnt = 0;
 208
 209         class_for_each_device(&mISDN_class, NULL, &cnt, _get_mdevice_count);
 210         return cnt;
 211 }
 212
 213 static int
 214 get_free_devid(void)
 215 {
 216         u_int   i;
 217
 218         for (i = 0; i <= MAX_DEVICE_ID; i++)
 219                 if (!test_and_set_bit(i, (u_long *)&device_ids))
 220                         break;
 221         if (i > MAX_DEVICE_ID)
 222                 return -EBUSY;
 223         return i;
 224 }
 225
 226 int
 227 mISDN_register_device(struct mISDNdevice *dev,
 228                       struct device *parent, char *name)
 229 {
 230         int     err;
 231
 232         err = get_free_devid();
 233         if (err < 0)
 234                 goto error1;
 235         dev->id = err;
 236
 237         device_initialize(&dev->dev);
 238         if (name && name[0])
 239                 dev_set_name(&dev->dev, "%s", name);
 240         else
 241                 dev_set_name(&dev->dev, "mISDN%d", dev->id);
 242         if (debug & DEBUG_CORE)
 243                 printk(KERN_DEBUG "mISDN_register %s %d\n",
 244                        dev_name(&dev->dev), dev->id);
 245         err = create_stack(dev);
 246         if (err)
 247                 goto error1;
 248
 249         dev->dev.class = &mISDN_class;
 250         dev->dev.platform_data = dev;
 251         dev->dev.parent = parent;
 252         dev_set_drvdata(&dev->dev, dev);
 253
 254         err = device_add(&dev->dev);
 255         if (err)
 256                 goto error3;
 257         return 0;
 258
 259 error3:
 260         delete_stack(dev);
 261         return err;
 262 error1:
 263         return err;
 264
 265 }
 266 EXPORT_SYMBOL(mISDN_register_device);
 267
 268 void
 269 mISDN_unregister_device(struct mISDNdevice *dev) {
 270         if (debug & DEBUG_CORE)
 271                 printk(KERN_DEBUG "mISDN_unregister %s %d\n",
 272                        dev_name(&dev->dev), dev->id);
 273         /* sysfs_remove_link(&dev->dev.kobj, "device"); */
 274         device_del(&dev->dev);
 275         dev_set_drvdata(&dev->dev, NULL);
 276
 277         test_and_clear_bit(dev->id, (u_long *)&device_ids);
 278         delete_stack(dev);
 279         put_device(&dev->dev);
 280 }
 281 EXPORT_SYMBOL(mISDN_unregister_device);
 282
 283 u_int
 284 get_all_Bprotocols(void)
 285 {
 286         struct Bprotocol        *bp;
 287         u_int   m = 0;
 288
 289         read_lock(&bp_lock);
 290         list_for_each_entry(bp, &Bprotocols, list)
 291                 m |= bp->Bprotocols;
 292         read_unlock(&bp_lock);
 293         return m;
 294 }
 295
 296 struct Bprotocol *
 297 get_Bprotocol4mask(u_int m)
 298 {
 299         struct Bprotocol        *bp;
 300
 301         read_lock(&bp_lock);
 302         list_for_each_entry(bp, &Bprotocols, list)
 303                 if (bp->Bprotocols & m) {
 304                         read_unlock(&bp_lock);
 305                         return bp;
 306                 }
 307         read_unlock(&bp_lock);
 308         return NULL;
 309 }
 310
 311 struct Bprotocol *
 312 get_Bprotocol4id(u_int id)
 313 {
 314         u_int   m;
 315
 316         if (id < ISDN_P_B_START || id > 63) {
 317                 printk(KERN_WARNING "%s id not in range  %d\n",
 318                        __func__, id);
 319                 return NULL;
 320         }
 321         m = 1 << (id & ISDN_P_B_MASK);
 322         return get_Bprotocol4mask(m);
 323 }
 324
 325 int
 326 mISDN_register_Bprotocol(struct Bprotocol *bp)
 327 {
 328         u_long                  flags;
 329         struct Bprotocol        *old;
 330
 331         if (debug & DEBUG_CORE)
 332                 printk(KERN_DEBUG "%s: %s/%x\n", __func__,
 333                        bp->name, bp->Bprotocols);
 334         old = get_Bprotocol4mask(bp->Bprotocols);
 335         if (old) {
 336                 printk(KERN_WARNING
 337                        "register duplicate protocol old %s/%x new %s/%x\n",
 338                        old->name, old->Bprotocols, bp->name, bp->Bprotocols);
 339                 return -EBUSY;
 340         }
 341         write_lock_irqsave(&bp_lock, flags);
 342         list_add_tail(&bp->list, &Bprotocols);
 343         write_unlock_irqrestore(&bp_lock, flags);
 344         return 0;
 345 }
 346 EXPORT_SYMBOL(mISDN_register_Bprotocol);
 347
 348 void
 349 mISDN_unregister_Bprotocol(struct Bprotocol *bp)
 350 {
 351         u_long  flags;
 352
 353         if (debug & DEBUG_CORE)
 354                 printk(KERN_DEBUG "%s: %s/%x\n", __func__, bp->name,
 355                        bp->Bprotocols);
 356         write_lock_irqsave(&bp_lock, flags);
 357         list_del(&bp->list);
 358         write_unlock_irqrestore(&bp_lock, flags);
 359 }
 360 EXPORT_SYMBOL(mISDN_unregister_Bprotocol);
 361
 362 static const char *msg_no_channel = "<no channel>";
 363 static const char *msg_no_stack = "<no stack>";
 364 static const char *msg_no_stackdev = "<no stack device>";
 365
 366 const char *mISDNDevName4ch(struct mISDNchannel *ch)
 367 {
 368         if (!ch)
 369                 return msg_no_channel;
 370         if (!ch->st)
 371                 return msg_no_stack;
 372         if (!ch->st->dev)
 373                 return msg_no_stackdev;
 374         return dev_name(&ch->st->dev->dev);
 375 };
 376 EXPORT_SYMBOL(mISDNDevName4ch);
 377
 378 static int
 379 mISDNInit(void)
 380 {
 381         int     err;
 382
 383         printk(KERN_INFO "Modular ISDN core version %d.%d.%d\n",
 384                MISDN_MAJOR_VERSION, MISDN_MINOR_VERSION, MISDN_RELEASE);
 385         mISDN_init_clock(&debug);
 386         mISDN_initstack(&debug);
 387         err = class_register(&mISDN_class);
 388         if (err)
 389                 goto error1;
 390         err = mISDN_inittimer(&debug);
 391         if (err)
 392                 goto error2;
 393         err = l1_init(&debug);
 394         if (err)
 395                 goto error3;
 396         err = Isdnl2_Init(&debug);
 397         if (err)
 398                 goto error4;
 399         err = misdn_sock_init(&debug);
 400         if (err)
 401                 goto error5;
 402         return 0;
 403
 404 error5:
 405         Isdnl2_cleanup();
 406 error4:
 407         l1_cleanup();
 408 error3:
 409         mISDN_timer_cleanup();
 410 error2:
 411         class_unregister(&mISDN_class);
 412 error1:
 413         return err;
 414 }
 415
 416 static void mISDN_cleanup(void)
 417 {
 418         misdn_sock_cleanup();
 419         Isdnl2_cleanup();
 420         l1_cleanup();
 421         mISDN_timer_cleanup();
 422         class_unregister(&mISDN_class);
 423
 424         printk(KERN_DEBUG "mISDNcore unloaded\n");
 425 }
 426
 427 module_init(mISDNInit);
 428 module_exit(mISDN_cleanup);