drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *
   5  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
   6  *                       IBM Corporation
   7  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   9  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
  10  */
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/errno.h>
  15 #include <linux/err.h>
  16 #include <linux/slab.h>
  17 #include <linux/list.h>
  18 #include <linux/device.h>
  19 #include <linux/workqueue.h>
  20
  21 #include <asm/ccwdev.h>
  22 #include <asm/cio.h>
  23 #include <asm/param.h>          /* HZ */
  24
  25 #include "cio.h"
  26 #include "cio_debug.h"
  27 #include "css.h"
  28 #include "device.h"
  29 #include "ioasm.h"
  30
  31 /******************* bus type handling ***********************/
  32
  33 /* The Linux driver model distinguishes between a bus type and
  34  * the bus itself. Of course we only have one channel
  35  * subsystem driver and one channel system per machine, but
  36  * we still use the abstraction. T.R. says it's a good idea. */
  37 static int
  38 ccw_bus_match (struct device * dev, struct device_driver * drv)
  39 {
  40         struct ccw_device *cdev = to_ccwdev(dev);
  41         struct ccw_driver *cdrv = to_ccwdrv(drv);
  42         const struct ccw_device_id *ids = cdrv->ids, *found;
  43
  44         if (!ids)
  45                 return 0;
  46
  47         found = ccw_device_id_match(ids, &cdev->id);
  48         if (!found)
  49                 return 0;
  50
  51         cdev->id.driver_info = found->driver_info;
  52
  53         return 1;
  54 }
  55
  56 /* Store modalias string delimited by prefix/suffix string into buffer with
  57  * specified size. Return length of resulting string (excluding trailing '\0')
  58  * even if string doesn't fit buffer (snprintf semantics). */
  59 static int snprint_alias(char *buf, size_t size, const char *prefix,
  60                          struct ccw_device_id *id, const char *suffix)
  61 {
  62         int len;
  63
  64         len = snprintf(buf, size, "%sccw:t%04Xm%02X", prefix, id->cu_type,
  65                        id->cu_model);
  66         if (len > size)
  67                 return len;
  68         buf += len;
  69         size -= len;
  70
  71         if (id->dev_type != 0)
  72                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  73                                 id->dev_model, suffix);
  74         else
  75                 len += snprintf(buf, size, "dtdm%s", suffix);
  76
  77         return len;
  78 }
  79
  80 /* Set up environment variables for ccw device uevent. Return 0 on success,
  81  * non-zero otherwise. */
  82 static int ccw_uevent(struct device *dev, char **envp, int num_envp,
  83                       char *buffer, int buffer_size)
  84 {
  85         struct ccw_device *cdev = to_ccwdev(dev);
  86         struct ccw_device_id *id = &(cdev->id);
  87         int i = 0;
  88         int len;
  89
  90         /* CU_TYPE= */
  91         len = snprintf(buffer, buffer_size, "CU_TYPE=%04X", id->cu_type) + 1;
  92         if (len > buffer_size || i >= num_envp)
  93                 return -ENOMEM;
  94         envp[i++] = buffer;
  95         buffer += len;
  96         buffer_size -= len;
  97
  98         /* CU_MODEL= */
  99         len = snprintf(buffer, buffer_size, "CU_MODEL=%02X", id->cu_model) + 1;
 100         if (len > buffer_size || i >= num_envp)
 101                 return -ENOMEM;
 102         envp[i++] = buffer;
 103         buffer += len;
 104         buffer_size -= len;
 105
 106         /* The next two can be zero, that's ok for us */
 107         /* DEV_TYPE= */
 108         len = snprintf(buffer, buffer_size, "DEV_TYPE=%04X", id->dev_type) + 1;
 109         if (len > buffer_size || i >= num_envp)
 110                 return -ENOMEM;
 111         envp[i++] = buffer;
 112         buffer += len;
 113         buffer_size -= len;
 114
 115         /* DEV_MODEL= */
 116         len = snprintf(buffer, buffer_size, "DEV_MODEL=%02X",
 117                         (unsigned char) id->dev_model) + 1;
 118         if (len > buffer_size || i >= num_envp)
 119                 return -ENOMEM;
 120         envp[i++] = buffer;
 121         buffer += len;
 122         buffer_size -= len;
 123
 124         /* MODALIAS=  */
 125         len = snprint_alias(buffer, buffer_size, "MODALIAS=", id, "") + 1;
 126         if (len > buffer_size || i >= num_envp)
 127                 return -ENOMEM;
 128         envp[i++] = buffer;
 129         buffer += len;
 130         buffer_size -= len;
 131
 132         envp[i] = NULL;
 133
 134         return 0;
 135 }
 136
 137 struct bus_type ccw_bus_type;
 138
 139 static int io_subchannel_probe (struct subchannel *);
 140 static int io_subchannel_remove (struct subchannel *);
 141 void io_subchannel_irq (struct device *);
 142 static int io_subchannel_notify(struct device *, int);
 143 static void io_subchannel_verify(struct device *);
 144 static void io_subchannel_ioterm(struct device *);
 145 static void io_subchannel_shutdown(struct subchannel *);
 146
 147 struct css_driver io_subchannel_driver = {
 148         .subchannel_type = SUBCHANNEL_TYPE_IO,
 149         .drv = {
 150                 .name = "io_subchannel",
 151                 .bus  = &css_bus_type,
 152         },
 153         .irq = io_subchannel_irq,
 154         .notify = io_subchannel_notify,
 155         .verify = io_subchannel_verify,
 156         .termination = io_subchannel_ioterm,
 157         .probe = io_subchannel_probe,
 158         .remove = io_subchannel_remove,
 159         .shutdown = io_subchannel_shutdown,
 160 };
 161
 162 struct workqueue_struct *ccw_device_work;
 163 struct workqueue_struct *ccw_device_notify_work;
 164 wait_queue_head_t ccw_device_init_wq;
 165 atomic_t ccw_device_init_count;
 166
 167 static int __init
 168 init_ccw_bus_type (void)
 169 {
 170         int ret;
 171
 172         init_waitqueue_head(&ccw_device_init_wq);
 173         atomic_set(&ccw_device_init_count, 0);
 174
 175         ccw_device_work = create_singlethread_workqueue("cio");
 176         if (!ccw_device_work)
 177                 return -ENOMEM; /* FIXME: better errno ? */
 178         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 179         if (!ccw_device_notify_work) {
 180                 ret = -ENOMEM; /* FIXME: better errno ? */
 181                 goto out_err;
 182         }
 183         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 184         if (!slow_path_wq) {
 185                 ret = -ENOMEM; /* FIXME: better errno ? */
 186                 goto out_err;
 187         }
 188         if ((ret = bus_register (&ccw_bus_type)))
 189                 goto out_err;
 190
 191         if ((ret = driver_register(&io_subchannel_driver.drv)))
 192                 goto out_err;
 193
 194         wait_event(ccw_device_init_wq,
 195                    atomic_read(&ccw_device_init_count) == 0);
 196         flush_workqueue(ccw_device_work);
 197         return 0;
 198 out_err:
 199         if (ccw_device_work)
 200                 destroy_workqueue(ccw_device_work);
 201         if (ccw_device_notify_work)
 202                 destroy_workqueue(ccw_device_notify_work);
 203         if (slow_path_wq)
 204                 destroy_workqueue(slow_path_wq);
 205         return ret;
 206 }
 207
 208 static void __exit
 209 cleanup_ccw_bus_type (void)
 210 {
 211         driver_unregister(&io_subchannel_driver.drv);
 212         bus_unregister(&ccw_bus_type);
 213         destroy_workqueue(ccw_device_notify_work);
 214         destroy_workqueue(ccw_device_work);
 215 }
 216
 217 subsys_initcall(init_ccw_bus_type);
 218 module_exit(cleanup_ccw_bus_type);
 219
 220 /************************ device handling **************************/
 221
 222 /*
 223  * A ccw_device has some interfaces in sysfs in addition to the
 224  * standard ones.
 225  * The following entries are designed to export the information which
 226  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 227  * are obvious, so they don't have an entry :)
 228  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 229  */
 230 static ssize_t
 231 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 232 {
 233         struct subchannel *sch = to_subchannel(dev);
 234         struct ssd_info *ssd = &sch->ssd_info;
 235         ssize_t ret = 0;
 236         int chp;
 237
 238         for (chp = 0; chp < 8; chp++)
 239                 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
 240
 241         ret += sprintf (buf+ret, "\n");
 242         return min((ssize_t)PAGE_SIZE, ret);
 243 }
 244
 245 static ssize_t
 246 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 247 {
 248         struct subchannel *sch = to_subchannel(dev);
 249         struct pmcw *pmcw = &sch->schib.pmcw;
 250
 251         return sprintf (buf, "%02x %02x %02x\n",
 252                         pmcw->pim, pmcw->pam, pmcw->pom);
 253 }
 254
 255 static ssize_t
 256 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 257 {
 258         struct ccw_device *cdev = to_ccwdev(dev);
 259         struct ccw_device_id *id = &(cdev->id);
 260
 261         if (id->dev_type != 0)
 262                 return sprintf(buf, "%04x/%02x\n",
 263                                 id->dev_type, id->dev_model);
 264         else
 265                 return sprintf(buf, "n/a\n");
 266 }
 267
 268 static ssize_t
 269 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 270 {
 271         struct ccw_device *cdev = to_ccwdev(dev);
 272         struct ccw_device_id *id = &(cdev->id);
 273
 274         return sprintf(buf, "%04x/%02x\n",
 275                        id->cu_type, id->cu_model);
 276 }
 277
 278 static ssize_t
 279 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 280 {
 281         struct ccw_device *cdev = to_ccwdev(dev);
 282         struct ccw_device_id *id = &(cdev->id);
 283         int len;
 284
 285         len = snprint_alias(buf, PAGE_SIZE, "", id, "\n") + 1;
 286
 287         return len > PAGE_SIZE ? PAGE_SIZE : len;
 288 }
 289
 290 static ssize_t
 291 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 292 {
 293         struct ccw_device *cdev = to_ccwdev(dev);
 294
 295         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 296 }
 297
 298 int ccw_device_is_orphan(struct ccw_device *cdev)
 299 {
 300         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 301 }
 302
 303 static void ccw_device_unregister(struct work_struct *work)
 304 {
 305         struct ccw_device_private *priv;
 306         struct ccw_device *cdev;
 307
 308         priv = container_of(work, struct ccw_device_private, kick_work);
 309         cdev = priv->cdev;
 310         if (test_and_clear_bit(1, &cdev->private->registered))
 311                 device_unregister(&cdev->dev);
 312         put_device(&cdev->dev);
 313 }
 314
 315 static void
 316 ccw_device_remove_disconnected(struct ccw_device *cdev)
 317 {
 318         struct subchannel *sch;
 319         unsigned long flags;
 320         /*
 321          * Forced offline in disconnected state means
 322          * 'throw away device'.
 323          */
 324         if (ccw_device_is_orphan(cdev)) {
 325                 /* Deregister ccw device. */
 326                 spin_lock_irqsave(cdev->ccwlock, flags);
 327                 cdev->private->state = DEV_STATE_NOT_OPER;
 328                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 329                 if (get_device(&cdev->dev)) {
 330                         PREPARE_WORK(&cdev->private->kick_work,
 331                                      ccw_device_unregister);
 332                         queue_work(ccw_device_work, &cdev->private->kick_work);
 333                 }
 334                 return ;
 335         }
 336         sch = to_subchannel(cdev->dev.parent);
 337         css_sch_device_unregister(sch);
 338         /* Reset intparm to zeroes. */
 339         sch->schib.pmcw.intparm = 0;
 340         cio_modify(sch);
 341         put_device(&sch->dev);
 342 }
 343
 344 int
 345 ccw_device_set_offline(struct ccw_device *cdev)
 346 {
 347         int ret;
 348
 349         if (!cdev)
 350                 return -ENODEV;
 351         if (!cdev->online || !cdev->drv)
 352                 return -EINVAL;
 353
 354         if (cdev->drv->set_offline) {
 355                 ret = cdev->drv->set_offline(cdev);
 356                 if (ret != 0)
 357                         return ret;
 358         }
 359         cdev->online = 0;
 360         spin_lock_irq(cdev->ccwlock);
 361         ret = ccw_device_offline(cdev);
 362         if (ret == -ENODEV) {
 363                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 364                         cdev->private->state = DEV_STATE_OFFLINE;
 365                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 366                 }
 367                 spin_unlock_irq(cdev->ccwlock);
 368                 return ret;
 369         }
 370         spin_unlock_irq(cdev->ccwlock);
 371         if (ret == 0)
 372                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 373         else {
 374                 pr_debug("ccw_device_offline returned %d, device %s\n",
 375                          ret, cdev->dev.bus_id);
 376                 cdev->online = 1;
 377         }
 378         return ret;
 379 }
 380
 381 int
 382 ccw_device_set_online(struct ccw_device *cdev)
 383 {
 384         int ret;
 385
 386         if (!cdev)
 387                 return -ENODEV;
 388         if (cdev->online || !cdev->drv)
 389                 return -EINVAL;
 390
 391         spin_lock_irq(cdev->ccwlock);
 392         ret = ccw_device_online(cdev);
 393         spin_unlock_irq(cdev->ccwlock);
 394         if (ret == 0)
 395                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 396         else {
 397                 pr_debug("ccw_device_online returned %d, device %s\n",
 398                          ret, cdev->dev.bus_id);
 399                 return ret;
 400         }
 401         if (cdev->private->state != DEV_STATE_ONLINE)
 402                 return -ENODEV;
 403         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 404                 cdev->online = 1;
 405                 return 0;
 406         }
 407         spin_lock_irq(cdev->ccwlock);
 408         ret = ccw_device_offline(cdev);
 409         spin_unlock_irq(cdev->ccwlock);
 410         if (ret == 0)
 411                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 412         else
 413                 pr_debug("ccw_device_offline returned %d, device %s\n",
 414                          ret, cdev->dev.bus_id);
 415         return (ret == 0) ? -ENODEV : ret;
 416 }
 417
 418 static ssize_t
 419 online_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 420 {
 421         struct ccw_device *cdev = to_ccwdev(dev);
 422         int i, force, ret;
 423         char *tmp;
 424
 425         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 426                 return -EAGAIN;
 427
 428         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 429                 atomic_set(&cdev->private->onoff, 0);
 430                 return -EINVAL;
 431         }
 432         if (!strncmp(buf, "force\n", count)) {
 433                 force = 1;
 434                 i = 1;
 435         } else {
 436                 force = 0;
 437                 i = simple_strtoul(buf, &tmp, 16);
 438         }
 439         if (i == 1) {
 440                 /* Do device recognition, if needed. */
 441                 if (cdev->id.cu_type == 0) {
 442                         ret = ccw_device_recognition(cdev);
 443                         if (ret) {
 444                                 printk(KERN_WARNING"Couldn't start recognition "
 445                                        "for device %s (ret=%d)\n",
 446                                        cdev->dev.bus_id, ret);
 447                                 goto out;
 448                         }
 449                         wait_event(cdev->private->wait_q,
 450                                    cdev->private->flags.recog_done);
 451                 }
 452                 if (cdev->drv && cdev->drv->set_online)
 453                         ccw_device_set_online(cdev);
 454         } else if (i == 0) {
 455                 if (cdev->private->state == DEV_STATE_DISCONNECTED)
 456                         ccw_device_remove_disconnected(cdev);
 457                 else if (cdev->drv && cdev->drv->set_offline)
 458                         ccw_device_set_offline(cdev);
 459         }
 460         if (force && cdev->private->state == DEV_STATE_BOXED) {
 461                 ret = ccw_device_stlck(cdev);
 462                 if (ret) {
 463                         printk(KERN_WARNING"ccw_device_stlck for device %s "
 464                                "returned %d!\n", cdev->dev.bus_id, ret);
 465                         goto out;
 466                 }
 467                 /* Do device recognition, if needed. */
 468                 if (cdev->id.cu_type == 0) {
 469                         cdev->private->state = DEV_STATE_NOT_OPER;
 470                         ret = ccw_device_recognition(cdev);
 471                         if (ret) {
 472                                 printk(KERN_WARNING"Couldn't start recognition "
 473                                        "for device %s (ret=%d)\n",
 474                                        cdev->dev.bus_id, ret);
 475                                 goto out;
 476                         }
 477                         wait_event(cdev->private->wait_q,
 478                                    cdev->private->flags.recog_done);
 479                 }
 480                 if (cdev->drv && cdev->drv->set_online)
 481                         ccw_device_set_online(cdev);
 482         }
 483         out:
 484         if (cdev->drv)
 485                 module_put(cdev->drv->owner);
 486         atomic_set(&cdev->private->onoff, 0);
 487         return count;
 488 }
 489
 490 static ssize_t
 491 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 492 {
 493         struct ccw_device *cdev = to_ccwdev(dev);
 494         struct subchannel *sch;
 495
 496         if (ccw_device_is_orphan(cdev))
 497                 return sprintf(buf, "no device\n");
 498         switch (cdev->private->state) {
 499         case DEV_STATE_BOXED:
 500                 return sprintf(buf, "boxed\n");
 501         case DEV_STATE_DISCONNECTED:
 502         case DEV_STATE_DISCONNECTED_SENSE_ID:
 503         case DEV_STATE_NOT_OPER:
 504                 sch = to_subchannel(dev->parent);
 505                 if (!sch->lpm)
 506                         return sprintf(buf, "no path\n");
 507                 else
 508                         return sprintf(buf, "no device\n");
 509         default:
 510                 /* All other states considered fine. */
 511                 return sprintf(buf, "good\n");
 512         }
 513 }
 514
 515 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 516 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 517 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 518 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 519 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 520 static DEVICE_ATTR(online, 0644, online_show, online_store);
 521 extern struct device_attribute dev_attr_cmb_enable;
 522 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 523
 524 static struct attribute * subch_attrs[] = {
 525         &dev_attr_chpids.attr,
 526         &dev_attr_pimpampom.attr,
 527         NULL,
 528 };
 529
 530 static struct attribute_group subch_attr_group = {
 531         .attrs = subch_attrs,
 532 };
 533
 534 int subchannel_add_files (struct device *dev)
 535 {
 536         return sysfs_create_group(&dev->kobj, &subch_attr_group);
 537 }
 538
 539 static struct attribute * ccwdev_attrs[] = {
 540         &dev_attr_devtype.attr,
 541         &dev_attr_cutype.attr,
 542         &dev_attr_modalias.attr,
 543         &dev_attr_online.attr,
 544         &dev_attr_cmb_enable.attr,
 545         &dev_attr_availability.attr,
 546         NULL,
 547 };
 548
 549 static struct attribute_group ccwdev_attr_group = {
 550         .attrs = ccwdev_attrs,
 551 };
 552
 553 static inline int
 554 device_add_files (struct device *dev)
 555 {
 556         return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
 557 }
 558
 559 static inline void
 560 device_remove_files(struct device *dev)
 561 {
 562         sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
 563 }
 564
 565 /* this is a simple abstraction for device_register that sets the
 566  * correct bus type and adds the bus specific files */
 567 static int ccw_device_register(struct ccw_device *cdev)
 568 {
 569         struct device *dev = &cdev->dev;
 570         int ret;
 571
 572         dev->bus = &ccw_bus_type;
 573
 574         if ((ret = device_add(dev)))
 575                 return ret;
 576
 577         set_bit(1, &cdev->private->registered);
 578         if ((ret = device_add_files(dev))) {
 579                 if (test_and_clear_bit(1, &cdev->private->registered))
 580                         device_del(dev);
 581         }
 582         return ret;
 583 }
 584
 585 struct match_data {
 586         struct ccw_dev_id dev_id;
 587         struct ccw_device * sibling;
 588 };
 589
 590 static int
 591 match_devno(struct device * dev, void * data)
 592 {
 593         struct match_data * d = data;
 594         struct ccw_device * cdev;
 595
 596         cdev = to_ccwdev(dev);
 597         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 598             !ccw_device_is_orphan(cdev) &&
 599             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 600             (cdev != d->sibling))
 601                 return 1;
 602         return 0;
 603 }
 604
 605 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 606                                                      struct ccw_device *sibling)
 607 {
 608         struct device *dev;
 609         struct match_data data;
 610
 611         data.dev_id = *dev_id;
 612         data.sibling = sibling;
 613         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 614
 615         return dev ? to_ccwdev(dev) : NULL;
 616 }
 617
 618 static int match_orphan(struct device *dev, void *data)
 619 {
 620         struct ccw_dev_id *dev_id;
 621         struct ccw_device *cdev;
 622
 623         dev_id = data;
 624         cdev = to_ccwdev(dev);
 625         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 626 }
 627
 628 static struct ccw_device *
 629 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 630                               struct ccw_dev_id *dev_id)
 631 {
 632         struct device *dev;
 633
 634         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 635                                 match_orphan);
 636
 637         return dev ? to_ccwdev(dev) : NULL;
 638 }
 639
 640 static void
 641 ccw_device_add_changed(struct work_struct *work)
 642 {
 643         struct ccw_device_private *priv;
 644         struct ccw_device *cdev;
 645
 646         priv = container_of(work, struct ccw_device_private, kick_work);
 647         cdev = priv->cdev;
 648         if (device_add(&cdev->dev)) {
 649                 put_device(&cdev->dev);
 650                 return;
 651         }
 652         set_bit(1, &cdev->private->registered);
 653         if (device_add_files(&cdev->dev)) {
 654                 if (test_and_clear_bit(1, &cdev->private->registered))
 655                         device_unregister(&cdev->dev);
 656         }
 657 }
 658
 659 void ccw_device_do_unreg_rereg(struct work_struct *work)
 660 {
 661         struct ccw_device_private *priv;
 662         struct ccw_device *cdev;
 663         struct subchannel *sch;
 664
 665         priv = container_of(work, struct ccw_device_private, kick_work);
 666         cdev = priv->cdev;
 667         sch = to_subchannel(cdev->dev.parent);
 668
 669         device_remove_files(&cdev->dev);
 670         if (test_and_clear_bit(1, &cdev->private->registered))
 671                 device_del(&cdev->dev);
 672         PREPARE_WORK(&cdev->private->kick_work,
 673                      ccw_device_add_changed);
 674         queue_work(ccw_device_work, &cdev->private->kick_work);
 675 }
 676
 677 static void
 678 ccw_device_release(struct device *dev)
 679 {
 680         struct ccw_device *cdev;
 681
 682         cdev = to_ccwdev(dev);
 683         kfree(cdev->private);
 684         kfree(cdev);
 685 }
 686
 687 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 688 {
 689         struct ccw_device *cdev;
 690
 691         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 692         if (cdev) {
 693                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 694                                         GFP_KERNEL | GFP_DMA);
 695                 if (cdev->private)
 696                         return cdev;
 697         }
 698         kfree(cdev);
 699         return ERR_PTR(-ENOMEM);
 700 }
 701
 702 static int io_subchannel_initialize_dev(struct subchannel *sch,
 703                                         struct ccw_device *cdev)
 704 {
 705         cdev->private->cdev = cdev;
 706         atomic_set(&cdev->private->onoff, 0);
 707         cdev->dev.parent = &sch->dev;
 708         cdev->dev.release = ccw_device_release;
 709         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
 710         /* Do first half of device_register. */
 711         device_initialize(&cdev->dev);
 712         if (!get_device(&sch->dev)) {
 713                 if (cdev->dev.release)
 714                         cdev->dev.release(&cdev->dev);
 715                 return -ENODEV;
 716         }
 717         return 0;
 718 }
 719
 720 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 721 {
 722         struct ccw_device *cdev;
 723         int ret;
 724
 725         cdev = io_subchannel_allocate_dev(sch);
 726         if (!IS_ERR(cdev)) {
 727                 ret = io_subchannel_initialize_dev(sch, cdev);
 728                 if (ret) {
 729                         kfree(cdev);
 730                         cdev = ERR_PTR(ret);
 731                 }
 732         }
 733         return cdev;
 734 }
 735
 736 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 737
 738 static void sch_attach_device(struct subchannel *sch,
 739                               struct ccw_device *cdev)
 740 {
 741         spin_lock_irq(sch->lock);
 742         sch->dev.driver_data = cdev;
 743         cdev->private->schid = sch->schid;
 744         cdev->ccwlock = sch->lock;
 745         device_trigger_reprobe(sch);
 746         spin_unlock_irq(sch->lock);
 747 }
 748
 749 static void sch_attach_disconnected_device(struct subchannel *sch,
 750                                            struct ccw_device *cdev)
 751 {
 752         struct subchannel *other_sch;
 753         int ret;
 754
 755         other_sch = to_subchannel(get_device(cdev->dev.parent));
 756         ret = device_move(&cdev->dev, &sch->dev);
 757         if (ret) {
 758                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
 759                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 760                               cdev->private->dev_id.devno, ret);
 761                 put_device(&other_sch->dev);
 762                 return;
 763         }
 764         other_sch->dev.driver_data = NULL;
 765         /* No need to keep a subchannel without ccw device around. */
 766         css_sch_device_unregister(other_sch);
 767         put_device(&other_sch->dev);
 768         sch_attach_device(sch, cdev);
 769 }
 770
 771 static void sch_attach_orphaned_device(struct subchannel *sch,
 772                                        struct ccw_device *cdev)
 773 {
 774         int ret;
 775
 776         /* Try to move the ccw device to its new subchannel. */
 777         ret = device_move(&cdev->dev, &sch->dev);
 778         if (ret) {
 779                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 780                               "failed (ret=%d)!\n",
 781                               cdev->private->dev_id.ssid,
 782                               cdev->private->dev_id.devno, ret);
 783                 return;
 784         }
 785         sch_attach_device(sch, cdev);
 786 }
 787
 788 static void sch_create_and_recog_new_device(struct subchannel *sch)
 789 {
 790         struct ccw_device *cdev;
 791
 792         /* Need to allocate a new ccw device. */
 793         cdev = io_subchannel_create_ccwdev(sch);
 794         if (IS_ERR(cdev)) {
 795                 /* OK, we did everything we could... */
 796                 css_sch_device_unregister(sch);
 797                 return;
 798         }
 799         spin_lock_irq(sch->lock);
 800         sch->dev.driver_data = cdev;
 801         spin_unlock_irq(sch->lock);
 802         /* Start recognition for the new ccw device. */
 803         if (io_subchannel_recog(cdev, sch)) {
 804                 spin_lock_irq(sch->lock);
 805                 sch->dev.driver_data = NULL;
 806                 spin_unlock_irq(sch->lock);
 807                 if (cdev->dev.release)
 808                         cdev->dev.release(&cdev->dev);
 809                 css_sch_device_unregister(sch);
 810         }
 811 }
 812
 813
 814 void ccw_device_move_to_orphanage(struct work_struct *work)
 815 {
 816         struct ccw_device_private *priv;
 817         struct ccw_device *cdev;
 818         struct ccw_device *replacing_cdev;
 819         struct subchannel *sch;
 820         int ret;
 821         struct channel_subsystem *css;
 822         struct ccw_dev_id dev_id;
 823
 824         priv = container_of(work, struct ccw_device_private, kick_work);
 825         cdev = priv->cdev;
 826         sch = to_subchannel(cdev->dev.parent);
 827         css = to_css(sch->dev.parent);
 828         dev_id.devno = sch->schib.pmcw.dev;
 829         dev_id.ssid = sch->schid.ssid;
 830
 831         /*
 832          * Move the orphaned ccw device to the orphanage so the replacing
 833          * ccw device can take its place on the subchannel.
 834          */
 835         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 836         if (ret) {
 837                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 838                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 839                               cdev->private->dev_id.devno, ret);
 840                 return;
 841         }
 842         cdev->ccwlock = css->pseudo_subchannel->lock;
 843         /*
 844          * Search for the replacing ccw device
 845          * - among the disconnected devices
 846          * - in the orphanage
 847          */
 848         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 849         if (replacing_cdev) {
 850                 sch_attach_disconnected_device(sch, replacing_cdev);
 851                 return;
 852         }
 853         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 854         if (replacing_cdev) {
 855                 sch_attach_orphaned_device(sch, replacing_cdev);
 856                 return;
 857         }
 858         sch_create_and_recog_new_device(sch);
 859 }
 860
 861 /*
 862  * Register recognized device.
 863  */
 864 static void
 865 io_subchannel_register(struct work_struct *work)
 866 {
 867         struct ccw_device_private *priv;
 868         struct ccw_device *cdev;
 869         struct subchannel *sch;
 870         int ret;
 871         unsigned long flags;
 872
 873         priv = container_of(work, struct ccw_device_private, kick_work);
 874         cdev = priv->cdev;
 875         sch = to_subchannel(cdev->dev.parent);
 876
 877         /*
 878          * io_subchannel_register() will also be called after device
 879          * recognition has been done for a boxed device (which will already
 880          * be registered). We need to reprobe since we may now have sense id
 881          * information.
 882          */
 883         if (klist_node_attached(&cdev->dev.knode_parent)) {
 884                 if (!cdev->drv) {
 885                         ret = device_reprobe(&cdev->dev);
 886                         if (ret)
 887                                 /* We can't do much here. */
 888                                 dev_info(&cdev->dev, "device_reprobe() returned"
 889                                          " %d\n", ret);
 890                 }
 891                 goto out;
 892         }
 893         /* make it known to the system */
 894         ret = ccw_device_register(cdev);
 895         if (ret) {
 896                 printk (KERN_WARNING "%s: could not register %s\n",
 897                         __func__, cdev->dev.bus_id);
 898                 put_device(&cdev->dev);
 899                 spin_lock_irqsave(sch->lock, flags);
 900                 sch->dev.driver_data = NULL;
 901                 spin_unlock_irqrestore(sch->lock, flags);
 902                 kfree (cdev->private);
 903                 kfree (cdev);
 904                 put_device(&sch->dev);
 905                 if (atomic_dec_and_test(&ccw_device_init_count))
 906                         wake_up(&ccw_device_init_wq);
 907                 return;
 908         }
 909         put_device(&cdev->dev);
 910 out:
 911         cdev->private->flags.recog_done = 1;
 912         put_device(&sch->dev);
 913         wake_up(&cdev->private->wait_q);
 914         if (atomic_dec_and_test(&ccw_device_init_count))
 915                 wake_up(&ccw_device_init_wq);
 916 }
 917
 918 void
 919 ccw_device_call_sch_unregister(struct work_struct *work)
 920 {
 921         struct ccw_device_private *priv;
 922         struct ccw_device *cdev;
 923         struct subchannel *sch;
 924
 925         priv = container_of(work, struct ccw_device_private, kick_work);
 926         cdev = priv->cdev;
 927         sch = to_subchannel(cdev->dev.parent);
 928         css_sch_device_unregister(sch);
 929         /* Reset intparm to zeroes. */
 930         sch->schib.pmcw.intparm = 0;
 931         cio_modify(sch);
 932         put_device(&cdev->dev);
 933         put_device(&sch->dev);
 934 }
 935
 936 /*
 937  * subchannel recognition done. Called from the state machine.
 938  */
 939 void
 940 io_subchannel_recog_done(struct ccw_device *cdev)
 941 {
 942         struct subchannel *sch;
 943
 944         if (css_init_done == 0) {
 945                 cdev->private->flags.recog_done = 1;
 946                 return;
 947         }
 948         switch (cdev->private->state) {
 949         case DEV_STATE_NOT_OPER:
 950                 cdev->private->flags.recog_done = 1;
 951                 /* Remove device found not operational. */
 952                 if (!get_device(&cdev->dev))
 953                         break;
 954                 sch = to_subchannel(cdev->dev.parent);
 955                 PREPARE_WORK(&cdev->private->kick_work,
 956                              ccw_device_call_sch_unregister);
 957                 queue_work(slow_path_wq, &cdev->private->kick_work);
 958                 if (atomic_dec_and_test(&ccw_device_init_count))
 959                         wake_up(&ccw_device_init_wq);
 960                 break;
 961         case DEV_STATE_BOXED:
 962                 /* Device did not respond in time. */
 963         case DEV_STATE_OFFLINE:
 964                 /*
 965                  * We can't register the device in interrupt context so
 966                  * we schedule a work item.
 967                  */
 968                 if (!get_device(&cdev->dev))
 969                         break;
 970                 PREPARE_WORK(&cdev->private->kick_work,
 971                              io_subchannel_register);
 972                 queue_work(slow_path_wq, &cdev->private->kick_work);
 973                 break;
 974         }
 975 }
 976
 977 static int
 978 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 979 {
 980         int rc;
 981         struct ccw_device_private *priv;
 982
 983         sch->dev.driver_data = cdev;
 984         sch->driver = &io_subchannel_driver;
 985         cdev->ccwlock = sch->lock;
 986
 987         /* Init private data. */
 988         priv = cdev->private;
 989         priv->dev_id.devno = sch->schib.pmcw.dev;
 990         priv->dev_id.ssid = sch->schid.ssid;
 991         priv->schid = sch->schid;
 992         priv->state = DEV_STATE_NOT_OPER;
 993         INIT_LIST_HEAD(&priv->cmb_list);
 994         init_waitqueue_head(&priv->wait_q);
 995         init_timer(&priv->timer);
 996
 997         /* Set an initial name for the device. */
 998         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
 999                   sch->schid.ssid, sch->schib.pmcw.dev);
1000
1001         /* Increase counter of devices currently in recognition. */
1002         atomic_inc(&ccw_device_init_count);
1003
1004         /* Start async. device sensing. */
1005         spin_lock_irq(sch->lock);
1006         rc = ccw_device_recognition(cdev);
1007         spin_unlock_irq(sch->lock);
1008         if (rc) {
1009                 if (atomic_dec_and_test(&ccw_device_init_count))
1010                         wake_up(&ccw_device_init_wq);
1011         }
1012         return rc;
1013 }
1014
1015 static void ccw_device_move_to_sch(struct work_struct *work)
1016 {
1017         struct ccw_device_private *priv;
1018         int rc;
1019         struct subchannel *sch;
1020         struct ccw_device *cdev;
1021         struct subchannel *former_parent;
1022
1023         priv = container_of(work, struct ccw_device_private, kick_work);
1024         sch = priv->sch;
1025         cdev = priv->cdev;
1026         former_parent = ccw_device_is_orphan(cdev) ?
1027                 NULL : to_subchannel(get_device(cdev->dev.parent));
1028         mutex_lock(&sch->reg_mutex);
1029         /* Try to move the ccw device to its new subchannel. */
1030         rc = device_move(&cdev->dev, &sch->dev);
1031         mutex_unlock(&sch->reg_mutex);
1032         if (rc) {
1033                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1034                               "0.%x.%04x failed (ret=%d)!\n",
1035                               cdev->private->dev_id.ssid,
1036                               cdev->private->dev_id.devno, sch->schid.ssid,
1037                               sch->schid.sch_no, rc);
1038                 css_sch_device_unregister(sch);
1039                 goto out;
1040         }
1041         if (former_parent) {
1042                 spin_lock_irq(former_parent->lock);
1043                 former_parent->dev.driver_data = NULL;
1044                 spin_unlock_irq(former_parent->lock);
1045                 css_sch_device_unregister(former_parent);
1046                 /* Reset intparm to zeroes. */
1047                 former_parent->schib.pmcw.intparm = 0;
1048                 cio_modify(former_parent);
1049         }
1050         sch_attach_device(sch, cdev);
1051 out:
1052         if (former_parent)
1053                 put_device(&former_parent->dev);
1054         put_device(&cdev->dev);
1055 }
1056
1057 static int
1058 io_subchannel_probe (struct subchannel *sch)
1059 {
1060         struct ccw_device *cdev;
1061         int rc;
1062         unsigned long flags;
1063         struct ccw_dev_id dev_id;
1064
1065         if (sch->dev.driver_data) {
1066                 /*
1067                  * This subchannel already has an associated ccw_device.
1068                  * Register it and exit. This happens for all early
1069                  * device, e.g. the console.
1070                  */
1071                 cdev = sch->dev.driver_data;
1072                 device_initialize(&cdev->dev);
1073                 ccw_device_register(cdev);
1074                 /*
1075                  * Check if the device is already online. If it is
1076                  * the reference count needs to be corrected
1077                  * (see ccw_device_online and css_init_done for the
1078                  * ugly details).
1079                  */
1080                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1081                     cdev->private->state != DEV_STATE_OFFLINE &&
1082                     cdev->private->state != DEV_STATE_BOXED)
1083                         get_device(&cdev->dev);
1084                 return 0;
1085         }
1086         /*
1087          * First check if a fitting device may be found amongst the
1088          * disconnected devices or in the orphanage.
1089          */
1090         dev_id.devno = sch->schib.pmcw.dev;
1091         dev_id.ssid = sch->schid.ssid;
1092         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1093         if (!cdev)
1094                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1095                                                      &dev_id);
1096         if (cdev) {
1097                 /*
1098                  * Schedule moving the device until when we have a registered
1099                  * subchannel to move to and succeed the probe. We can
1100                  * unregister later again, when the probe is through.
1101                  */
1102                 cdev->private->sch = sch;
1103                 PREPARE_WORK(&cdev->private->kick_work,
1104                              ccw_device_move_to_sch);
1105                 queue_work(slow_path_wq, &cdev->private->kick_work);
1106                 return 0;
1107         }
1108         cdev = io_subchannel_create_ccwdev(sch);
1109         if (IS_ERR(cdev))
1110                 return PTR_ERR(cdev);
1111
1112         rc = io_subchannel_recog(cdev, sch);
1113         if (rc) {
1114                 spin_lock_irqsave(sch->lock, flags);
1115                 sch->dev.driver_data = NULL;
1116                 spin_unlock_irqrestore(sch->lock, flags);
1117                 if (cdev->dev.release)
1118                         cdev->dev.release(&cdev->dev);
1119         }
1120
1121         return rc;
1122 }
1123
1124 static int
1125 io_subchannel_remove (struct subchannel *sch)
1126 {
1127         struct ccw_device *cdev;
1128         unsigned long flags;
1129
1130         if (!sch->dev.driver_data)
1131                 return 0;
1132         cdev = sch->dev.driver_data;
1133         /* Set ccw device to not operational and drop reference. */
1134         spin_lock_irqsave(cdev->ccwlock, flags);
1135         sch->dev.driver_data = NULL;
1136         cdev->private->state = DEV_STATE_NOT_OPER;
1137         spin_unlock_irqrestore(cdev->ccwlock, flags);
1138         /*
1139          * Put unregistration on workqueue to avoid livelocks on the css bus
1140          * semaphore.
1141          */
1142         if (get_device(&cdev->dev)) {
1143                 PREPARE_WORK(&cdev->private->kick_work,
1144                              ccw_device_unregister);
1145                 queue_work(ccw_device_work, &cdev->private->kick_work);
1146         }
1147         return 0;
1148 }
1149
1150 static int
1151 io_subchannel_notify(struct device *dev, int event)
1152 {
1153         struct ccw_device *cdev;
1154
1155         cdev = dev->driver_data;
1156         if (!cdev)
1157                 return 0;
1158         if (!cdev->drv)
1159                 return 0;
1160         if (!cdev->online)
1161                 return 0;
1162         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1163 }
1164
1165 static void
1166 io_subchannel_verify(struct device *dev)
1167 {
1168         struct ccw_device *cdev;
1169
1170         cdev = dev->driver_data;
1171         if (cdev)
1172                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1173 }
1174
1175 static void
1176 io_subchannel_ioterm(struct device *dev)
1177 {
1178         struct ccw_device *cdev;
1179
1180         cdev = dev->driver_data;
1181         if (!cdev)
1182                 return;
1183         /* Internal I/O will be retried by the interrupt handler. */
1184         if (cdev->private->flags.intretry)
1185                 return;
1186         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1187         if (cdev->handler)
1188                 cdev->handler(cdev, cdev->private->intparm,
1189                               ERR_PTR(-EIO));
1190 }
1191
1192 static void
1193 io_subchannel_shutdown(struct subchannel *sch)
1194 {
1195         struct ccw_device *cdev;
1196         int ret;
1197
1198         cdev = sch->dev.driver_data;
1199
1200         if (cio_is_console(sch->schid))
1201                 return;
1202         if (!sch->schib.pmcw.ena)
1203                 /* Nothing to do. */
1204                 return;
1205         ret = cio_disable_subchannel(sch);
1206         if (ret != -EBUSY)
1207                 /* Subchannel is disabled, we're done. */
1208                 return;
1209         cdev->private->state = DEV_STATE_QUIESCE;
1210         if (cdev->handler)
1211                 cdev->handler(cdev, cdev->private->intparm,
1212                               ERR_PTR(-EIO));
1213         ret = ccw_device_cancel_halt_clear(cdev);
1214         if (ret == -EBUSY) {
1215                 ccw_device_set_timeout(cdev, HZ/10);
1216                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1217         }
1218         cio_disable_subchannel(sch);
1219 }
1220
1221 #ifdef CONFIG_CCW_CONSOLE
1222 static struct ccw_device console_cdev;
1223 static struct ccw_device_private console_private;
1224 static int console_cdev_in_use;
1225
1226 static DEFINE_SPINLOCK(ccw_console_lock);
1227
1228 spinlock_t * cio_get_console_lock(void)
1229 {
1230         return &ccw_console_lock;
1231 }
1232
1233 static int
1234 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1235 {
1236         int rc;
1237
1238         /* Initialize the ccw_device structure. */
1239         cdev->dev.parent= &sch->dev;
1240         rc = io_subchannel_recog(cdev, sch);
1241         if (rc)
1242                 return rc;
1243
1244         /* Now wait for the async. recognition to come to an end. */
1245         spin_lock_irq(cdev->ccwlock);
1246         while (!dev_fsm_final_state(cdev))
1247                 wait_cons_dev();
1248         rc = -EIO;
1249         if (cdev->private->state != DEV_STATE_OFFLINE)
1250                 goto out_unlock;
1251         ccw_device_online(cdev);
1252         while (!dev_fsm_final_state(cdev))
1253                 wait_cons_dev();
1254         if (cdev->private->state != DEV_STATE_ONLINE)
1255                 goto out_unlock;
1256         rc = 0;
1257 out_unlock:
1258         spin_unlock_irq(cdev->ccwlock);
1259         return 0;
1260 }
1261
1262 struct ccw_device *
1263 ccw_device_probe_console(void)
1264 {
1265         struct subchannel *sch;
1266         int ret;
1267
1268         if (xchg(&console_cdev_in_use, 1) != 0)
1269                 return ERR_PTR(-EBUSY);
1270         sch = cio_probe_console();
1271         if (IS_ERR(sch)) {
1272                 console_cdev_in_use = 0;
1273                 return (void *) sch;
1274         }
1275         memset(&console_cdev, 0, sizeof(struct ccw_device));
1276         memset(&console_private, 0, sizeof(struct ccw_device_private));
1277         console_cdev.private = &console_private;
1278         console_private.cdev = &console_cdev;
1279         ret = ccw_device_console_enable(&console_cdev, sch);
1280         if (ret) {
1281                 cio_release_console();
1282                 console_cdev_in_use = 0;
1283                 return ERR_PTR(ret);
1284         }
1285         console_cdev.online = 1;
1286         return &console_cdev;
1287 }
1288 #endif
1289
1290 /*
1291  * get ccw_device matching the busid, but only if owned by cdrv
1292  */
1293 static int
1294 __ccwdev_check_busid(struct device *dev, void *id)
1295 {
1296         char *bus_id;
1297
1298         bus_id = id;
1299
1300         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1301 }
1302
1303
1304 struct ccw_device *
1305 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1306 {
1307         struct device *dev;
1308         struct device_driver *drv;
1309
1310         drv = get_driver(&cdrv->driver);
1311         if (!drv)
1312                 return NULL;
1313
1314         dev = driver_find_device(drv, NULL, (void *)bus_id,
1315                                  __ccwdev_check_busid);
1316         put_driver(drv);
1317
1318         return dev ? to_ccwdev(dev) : NULL;
1319 }
1320
1321 /************************** device driver handling ************************/
1322
1323 /* This is the implementation of the ccw_driver class. The probe, remove
1324  * and release methods are initially very similar to the device_driver
1325  * implementations, with the difference that they have ccw_device
1326  * arguments.
1327  *
1328  * A ccw driver also contains the information that is needed for
1329  * device matching.
1330  */
1331 static int
1332 ccw_device_probe (struct device *dev)
1333 {
1334         struct ccw_device *cdev = to_ccwdev(dev);
1335         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1336         int ret;
1337
1338         cdev->drv = cdrv; /* to let the driver call _set_online */
1339
1340         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1341
1342         if (ret) {
1343                 cdev->drv = NULL;
1344                 return ret;
1345         }
1346
1347         return 0;
1348 }
1349
1350 static int
1351 ccw_device_remove (struct device *dev)
1352 {
1353         struct ccw_device *cdev = to_ccwdev(dev);
1354         struct ccw_driver *cdrv = cdev->drv;
1355         int ret;
1356
1357         pr_debug("removing device %s\n", cdev->dev.bus_id);
1358         if (cdrv->remove)
1359                 cdrv->remove(cdev);
1360         if (cdev->online) {
1361                 cdev->online = 0;
1362                 spin_lock_irq(cdev->ccwlock);
1363                 ret = ccw_device_offline(cdev);
1364                 spin_unlock_irq(cdev->ccwlock);
1365                 if (ret == 0)
1366                         wait_event(cdev->private->wait_q,
1367                                    dev_fsm_final_state(cdev));
1368                 else
1369                         //FIXME: we can't fail!
1370                         pr_debug("ccw_device_offline returned %d, device %s\n",
1371                                  ret, cdev->dev.bus_id);
1372         }
1373         ccw_device_set_timeout(cdev, 0);
1374         cdev->drv = NULL;
1375         return 0;
1376 }
1377
1378 struct bus_type ccw_bus_type = {
1379         .name   = "ccw",
1380         .match  = ccw_bus_match,
1381         .uevent = ccw_uevent,
1382         .probe  = ccw_device_probe,
1383         .remove = ccw_device_remove,
1384 };
1385
1386 int
1387 ccw_driver_register (struct ccw_driver *cdriver)
1388 {
1389         struct device_driver *drv = &cdriver->driver;
1390
1391         drv->bus = &ccw_bus_type;
1392         drv->name = cdriver->name;
1393
1394         return driver_register(drv);
1395 }
1396
1397 void
1398 ccw_driver_unregister (struct ccw_driver *cdriver)
1399 {
1400         driver_unregister(&cdriver->driver);
1401 }
1402
1403 /* Helper func for qdio. */
1404 struct subchannel_id
1405 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1406 {
1407         struct subchannel *sch;
1408
1409         sch = to_subchannel(cdev->dev.parent);
1410         return sch->schid;
1411 }
1412
1413 MODULE_LICENSE("GPL");
1414 EXPORT_SYMBOL(ccw_device_set_online);
1415 EXPORT_SYMBOL(ccw_device_set_offline);
1416 EXPORT_SYMBOL(ccw_driver_register);
1417 EXPORT_SYMBOL(ccw_driver_unregister);
1418 EXPORT_SYMBOL(get_ccwdev_by_busid);
1419 EXPORT_SYMBOL(ccw_bus_type);
1420 EXPORT_SYMBOL(ccw_device_work);
1421 EXPORT_SYMBOL(ccw_device_notify_work);
1422 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);