git.oblomov.eu Git - linux-2.6/blob - 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,
  60                          struct ccw_device_id *id, const char *suffix)
  61 {
  62         int len;
  63
  64         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  65         if (len > size)
  66                 return len;
  67         buf += len;
  68         size -= len;
  69
  70         if (id->dev_type != 0)
  71                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  72                                 id->dev_model, suffix);
  73         else
  74                 len += snprintf(buf, size, "dtdm%s", suffix);
  75
  76         return len;
  77 }
  78
  79 /* Set up environment variables for ccw device uevent. Return 0 on success,
  80  * non-zero otherwise. */
  81 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  82 {
  83         struct ccw_device *cdev = to_ccwdev(dev);
  84         struct ccw_device_id *id = &(cdev->id);
  85         int ret;
  86         char modalias_buf[30];
  87
  88         /* CU_TYPE= */
  89         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
  90         if (ret)
  91                 return ret;
  92
  93         /* CU_MODEL= */
  94         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
  95         if (ret)
  96                 return ret;
  97
  98         /* The next two can be zero, that's ok for us */
  99         /* DEV_TYPE= */
 100         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 101         if (ret)
 102                 return ret;
 103
 104         /* DEV_MODEL= */
 105         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 106         if (ret)
 107                 return ret;
 108
 109         /* MODALIAS=  */
 110         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 111         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 112         return ret;
 113 }
 114
 115 struct bus_type ccw_bus_type;
 116
 117 static int io_subchannel_probe (struct subchannel *);
 118 static int io_subchannel_remove (struct subchannel *);
 119 static int io_subchannel_notify(struct device *, int);
 120 static void io_subchannel_verify(struct device *);
 121 static void io_subchannel_ioterm(struct device *);
 122 static void io_subchannel_shutdown(struct subchannel *);
 123
 124 static struct css_driver io_subchannel_driver = {
 125         .subchannel_type = SUBCHANNEL_TYPE_IO,
 126         .drv = {
 127                 .name = "io_subchannel",
 128                 .bus  = &css_bus_type,
 129         },
 130         .irq = io_subchannel_irq,
 131         .notify = io_subchannel_notify,
 132         .verify = io_subchannel_verify,
 133         .termination = io_subchannel_ioterm,
 134         .probe = io_subchannel_probe,
 135         .remove = io_subchannel_remove,
 136         .shutdown = io_subchannel_shutdown,
 137 };
 138
 139 struct workqueue_struct *ccw_device_work;
 140 struct workqueue_struct *ccw_device_notify_work;
 141 wait_queue_head_t ccw_device_init_wq;
 142 atomic_t ccw_device_init_count;
 143
 144 static int __init
 145 init_ccw_bus_type (void)
 146 {
 147         int ret;
 148
 149         init_waitqueue_head(&ccw_device_init_wq);
 150         atomic_set(&ccw_device_init_count, 0);
 151
 152         ccw_device_work = create_singlethread_workqueue("cio");
 153         if (!ccw_device_work)
 154                 return -ENOMEM; /* FIXME: better errno ? */
 155         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 156         if (!ccw_device_notify_work) {
 157                 ret = -ENOMEM; /* FIXME: better errno ? */
 158                 goto out_err;
 159         }
 160         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 161         if (!slow_path_wq) {
 162                 ret = -ENOMEM; /* FIXME: better errno ? */
 163                 goto out_err;
 164         }
 165         if ((ret = bus_register (&ccw_bus_type)))
 166                 goto out_err;
 167
 168         if ((ret = driver_register(&io_subchannel_driver.drv)))
 169                 goto out_err;
 170
 171         wait_event(ccw_device_init_wq,
 172                    atomic_read(&ccw_device_init_count) == 0);
 173         flush_workqueue(ccw_device_work);
 174         return 0;
 175 out_err:
 176         if (ccw_device_work)
 177                 destroy_workqueue(ccw_device_work);
 178         if (ccw_device_notify_work)
 179                 destroy_workqueue(ccw_device_notify_work);
 180         if (slow_path_wq)
 181                 destroy_workqueue(slow_path_wq);
 182         return ret;
 183 }
 184
 185 static void __exit
 186 cleanup_ccw_bus_type (void)
 187 {
 188         driver_unregister(&io_subchannel_driver.drv);
 189         bus_unregister(&ccw_bus_type);
 190         destroy_workqueue(ccw_device_notify_work);
 191         destroy_workqueue(ccw_device_work);
 192 }
 193
 194 subsys_initcall(init_ccw_bus_type);
 195 module_exit(cleanup_ccw_bus_type);
 196
 197 /************************ device handling **************************/
 198
 199 /*
 200  * A ccw_device has some interfaces in sysfs in addition to the
 201  * standard ones.
 202  * The following entries are designed to export the information which
 203  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 204  * are obvious, so they don't have an entry :)
 205  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 206  */
 207 static ssize_t
 208 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 209 {
 210         struct subchannel *sch = to_subchannel(dev);
 211         struct chsc_ssd_info *ssd = &sch->ssd_info;
 212         ssize_t ret = 0;
 213         int chp;
 214         int mask;
 215
 216         for (chp = 0; chp < 8; chp++) {
 217                 mask = 0x80 >> chp;
 218                 if (ssd->path_mask & mask)
 219                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 220                 else
 221                         ret += sprintf(buf + ret, "00 ");
 222         }
 223         ret += sprintf (buf+ret, "\n");
 224         return min((ssize_t)PAGE_SIZE, ret);
 225 }
 226
 227 static ssize_t
 228 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 229 {
 230         struct subchannel *sch = to_subchannel(dev);
 231         struct pmcw *pmcw = &sch->schib.pmcw;
 232
 233         return sprintf (buf, "%02x %02x %02x\n",
 234                         pmcw->pim, pmcw->pam, pmcw->pom);
 235 }
 236
 237 static ssize_t
 238 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 239 {
 240         struct ccw_device *cdev = to_ccwdev(dev);
 241         struct ccw_device_id *id = &(cdev->id);
 242
 243         if (id->dev_type != 0)
 244                 return sprintf(buf, "%04x/%02x\n",
 245                                 id->dev_type, id->dev_model);
 246         else
 247                 return sprintf(buf, "n/a\n");
 248 }
 249
 250 static ssize_t
 251 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 252 {
 253         struct ccw_device *cdev = to_ccwdev(dev);
 254         struct ccw_device_id *id = &(cdev->id);
 255
 256         return sprintf(buf, "%04x/%02x\n",
 257                        id->cu_type, id->cu_model);
 258 }
 259
 260 static ssize_t
 261 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 262 {
 263         struct ccw_device *cdev = to_ccwdev(dev);
 264         struct ccw_device_id *id = &(cdev->id);
 265         int len;
 266
 267         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 268
 269         return len > PAGE_SIZE ? PAGE_SIZE : len;
 270 }
 271
 272 static ssize_t
 273 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 274 {
 275         struct ccw_device *cdev = to_ccwdev(dev);
 276
 277         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 278 }
 279
 280 int ccw_device_is_orphan(struct ccw_device *cdev)
 281 {
 282         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 283 }
 284
 285 static void ccw_device_unregister(struct ccw_device *cdev)
 286 {
 287         if (test_and_clear_bit(1, &cdev->private->registered))
 288                 device_del(&cdev->dev);
 289 }
 290
 291 static void ccw_device_remove_orphan_cb(struct device *dev)
 292 {
 293         struct ccw_device *cdev = to_ccwdev(dev);
 294
 295         ccw_device_unregister(cdev);
 296         put_device(&cdev->dev);
 297 }
 298
 299 static void ccw_device_remove_sch_cb(struct device *dev)
 300 {
 301         struct subchannel *sch;
 302
 303         sch = to_subchannel(dev);
 304         css_sch_device_unregister(sch);
 305         /* Reset intparm to zeroes. */
 306         sch->schib.pmcw.intparm = 0;
 307         cio_modify(sch);
 308         put_device(&sch->dev);
 309 }
 310
 311 static void
 312 ccw_device_remove_disconnected(struct ccw_device *cdev)
 313 {
 314         unsigned long flags;
 315         int rc;
 316
 317         /*
 318          * Forced offline in disconnected state means
 319          * 'throw away device'.
 320          */
 321         if (ccw_device_is_orphan(cdev)) {
 322                 /*
 323                  * Deregister ccw device.
 324                  * Unfortunately, we cannot do this directly from the
 325                  * attribute method.
 326                  */
 327                 spin_lock_irqsave(cdev->ccwlock, flags);
 328                 cdev->private->state = DEV_STATE_NOT_OPER;
 329                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 330                 rc = device_schedule_callback(&cdev->dev,
 331                                               ccw_device_remove_orphan_cb);
 332                 if (rc)
 333                         CIO_MSG_EVENT(2, "Couldn't unregister orphan "
 334                                       "0.%x.%04x\n",
 335                                       cdev->private->dev_id.ssid,
 336                                       cdev->private->dev_id.devno);
 337                 return;
 338         }
 339         /* Deregister subchannel, which will kill the ccw device. */
 340         rc = device_schedule_callback(cdev->dev.parent,
 341                                       ccw_device_remove_sch_cb);
 342         if (rc)
 343                 CIO_MSG_EVENT(2, "Couldn't unregister disconnected device "
 344                               "0.%x.%04x\n",
 345                               cdev->private->dev_id.ssid,
 346                               cdev->private->dev_id.devno);
 347 }
 348
 349 int
 350 ccw_device_set_offline(struct ccw_device *cdev)
 351 {
 352         int ret;
 353
 354         if (!cdev)
 355                 return -ENODEV;
 356         if (!cdev->online || !cdev->drv)
 357                 return -EINVAL;
 358
 359         if (cdev->drv->set_offline) {
 360                 ret = cdev->drv->set_offline(cdev);
 361                 if (ret != 0)
 362                         return ret;
 363         }
 364         cdev->online = 0;
 365         spin_lock_irq(cdev->ccwlock);
 366         ret = ccw_device_offline(cdev);
 367         if (ret == -ENODEV) {
 368                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 369                         cdev->private->state = DEV_STATE_OFFLINE;
 370                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 371                 }
 372                 spin_unlock_irq(cdev->ccwlock);
 373                 return ret;
 374         }
 375         spin_unlock_irq(cdev->ccwlock);
 376         if (ret == 0)
 377                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 378         else {
 379                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 380                               "device 0.%x.%04x\n",
 381                               ret, cdev->private->dev_id.ssid,
 382                               cdev->private->dev_id.devno);
 383                 cdev->online = 1;
 384         }
 385         return ret;
 386 }
 387
 388 int
 389 ccw_device_set_online(struct ccw_device *cdev)
 390 {
 391         int ret;
 392
 393         if (!cdev)
 394                 return -ENODEV;
 395         if (cdev->online || !cdev->drv)
 396                 return -EINVAL;
 397
 398         spin_lock_irq(cdev->ccwlock);
 399         ret = ccw_device_online(cdev);
 400         spin_unlock_irq(cdev->ccwlock);
 401         if (ret == 0)
 402                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 403         else {
 404                 CIO_MSG_EVENT(2, "ccw_device_online returned %d, "
 405                               "device 0.%x.%04x\n",
 406                               ret, cdev->private->dev_id.ssid,
 407                               cdev->private->dev_id.devno);
 408                 return ret;
 409         }
 410         if (cdev->private->state != DEV_STATE_ONLINE)
 411                 return -ENODEV;
 412         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 413                 cdev->online = 1;
 414                 return 0;
 415         }
 416         spin_lock_irq(cdev->ccwlock);
 417         ret = ccw_device_offline(cdev);
 418         spin_unlock_irq(cdev->ccwlock);
 419         if (ret == 0)
 420                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 421         else
 422                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 423                               "device 0.%x.%04x\n",
 424                               ret, cdev->private->dev_id.ssid,
 425                               cdev->private->dev_id.devno);
 426         return (ret == 0) ? -ENODEV : ret;
 427 }
 428
 429 static void online_store_handle_offline(struct ccw_device *cdev)
 430 {
 431         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 432                 ccw_device_remove_disconnected(cdev);
 433         else if (cdev->drv && cdev->drv->set_offline)
 434                 ccw_device_set_offline(cdev);
 435 }
 436
 437 static int online_store_recog_and_online(struct ccw_device *cdev)
 438 {
 439         int ret;
 440
 441         /* Do device recognition, if needed. */
 442         if (cdev->id.cu_type == 0) {
 443                 ret = ccw_device_recognition(cdev);
 444                 if (ret) {
 445                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 446                                       "for device 0.%x.%04x (ret=%d)\n",
 447                                       cdev->private->dev_id.ssid,
 448                                       cdev->private->dev_id.devno, ret);
 449                         return ret;
 450                 }
 451                 wait_event(cdev->private->wait_q,
 452                            cdev->private->flags.recog_done);
 453         }
 454         if (cdev->drv && cdev->drv->set_online)
 455                 ccw_device_set_online(cdev);
 456         return 0;
 457 }
 458 static void online_store_handle_online(struct ccw_device *cdev, int force)
 459 {
 460         int ret;
 461
 462         ret = online_store_recog_and_online(cdev);
 463         if (ret)
 464                 return;
 465         if (force && cdev->private->state == DEV_STATE_BOXED) {
 466                 ret = ccw_device_stlck(cdev);
 467                 if (ret) {
 468                         dev_warn(&cdev->dev,
 469                                  "ccw_device_stlck returned %d!\n", ret);
 470                         return;
 471                 }
 472                 if (cdev->id.cu_type == 0)
 473                         cdev->private->state = DEV_STATE_NOT_OPER;
 474                 online_store_recog_and_online(cdev);
 475         }
 476
 477 }
 478
 479 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 480                              const char *buf, size_t count)
 481 {
 482         struct ccw_device *cdev = to_ccwdev(dev);
 483         int i, force;
 484         char *tmp;
 485
 486         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 487                 return -EAGAIN;
 488
 489         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 490                 atomic_set(&cdev->private->onoff, 0);
 491                 return -EINVAL;
 492         }
 493         if (!strncmp(buf, "force\n", count)) {
 494                 force = 1;
 495                 i = 1;
 496         } else {
 497                 force = 0;
 498                 i = simple_strtoul(buf, &tmp, 16);
 499         }
 500
 501         switch (i) {
 502         case 0:
 503                 online_store_handle_offline(cdev);
 504                 break;
 505         case 1:
 506                 online_store_handle_online(cdev, force);
 507                 break;
 508         default:
 509                 count = -EINVAL;
 510         }
 511         if (cdev->drv)
 512                 module_put(cdev->drv->owner);
 513         atomic_set(&cdev->private->onoff, 0);
 514         return count;
 515 }
 516
 517 static ssize_t
 518 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 519 {
 520         struct ccw_device *cdev = to_ccwdev(dev);
 521         struct subchannel *sch;
 522
 523         if (ccw_device_is_orphan(cdev))
 524                 return sprintf(buf, "no device\n");
 525         switch (cdev->private->state) {
 526         case DEV_STATE_BOXED:
 527                 return sprintf(buf, "boxed\n");
 528         case DEV_STATE_DISCONNECTED:
 529         case DEV_STATE_DISCONNECTED_SENSE_ID:
 530         case DEV_STATE_NOT_OPER:
 531                 sch = to_subchannel(dev->parent);
 532                 if (!sch->lpm)
 533                         return sprintf(buf, "no path\n");
 534                 else
 535                         return sprintf(buf, "no device\n");
 536         default:
 537                 /* All other states considered fine. */
 538                 return sprintf(buf, "good\n");
 539         }
 540 }
 541
 542 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 543 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 544 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 545 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 546 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 547 static DEVICE_ATTR(online, 0644, online_show, online_store);
 548 extern struct device_attribute dev_attr_cmb_enable;
 549 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 550
 551 static struct attribute * subch_attrs[] = {
 552         &dev_attr_chpids.attr,
 553         &dev_attr_pimpampom.attr,
 554         NULL,
 555 };
 556
 557 static struct attribute_group subch_attr_group = {
 558         .attrs = subch_attrs,
 559 };
 560
 561 struct attribute_group *subch_attr_groups[] = {
 562         &subch_attr_group,
 563         NULL,
 564 };
 565
 566 static struct attribute * ccwdev_attrs[] = {
 567         &dev_attr_devtype.attr,
 568         &dev_attr_cutype.attr,
 569         &dev_attr_modalias.attr,
 570         &dev_attr_online.attr,
 571         &dev_attr_cmb_enable.attr,
 572         &dev_attr_availability.attr,
 573         NULL,
 574 };
 575
 576 static struct attribute_group ccwdev_attr_group = {
 577         .attrs = ccwdev_attrs,
 578 };
 579
 580 static struct attribute_group *ccwdev_attr_groups[] = {
 581         &ccwdev_attr_group,
 582         NULL,
 583 };
 584
 585 /* this is a simple abstraction for device_register that sets the
 586  * correct bus type and adds the bus specific files */
 587 static int ccw_device_register(struct ccw_device *cdev)
 588 {
 589         struct device *dev = &cdev->dev;
 590         int ret;
 591
 592         dev->bus = &ccw_bus_type;
 593
 594         if ((ret = device_add(dev)))
 595                 return ret;
 596
 597         set_bit(1, &cdev->private->registered);
 598         return ret;
 599 }
 600
 601 struct match_data {
 602         struct ccw_dev_id dev_id;
 603         struct ccw_device * sibling;
 604 };
 605
 606 static int
 607 match_devno(struct device * dev, void * data)
 608 {
 609         struct match_data * d = data;
 610         struct ccw_device * cdev;
 611
 612         cdev = to_ccwdev(dev);
 613         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 614             !ccw_device_is_orphan(cdev) &&
 615             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 616             (cdev != d->sibling))
 617                 return 1;
 618         return 0;
 619 }
 620
 621 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 622                                                      struct ccw_device *sibling)
 623 {
 624         struct device *dev;
 625         struct match_data data;
 626
 627         data.dev_id = *dev_id;
 628         data.sibling = sibling;
 629         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 630
 631         return dev ? to_ccwdev(dev) : NULL;
 632 }
 633
 634 static int match_orphan(struct device *dev, void *data)
 635 {
 636         struct ccw_dev_id *dev_id;
 637         struct ccw_device *cdev;
 638
 639         dev_id = data;
 640         cdev = to_ccwdev(dev);
 641         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 642 }
 643
 644 static struct ccw_device *
 645 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 646                               struct ccw_dev_id *dev_id)
 647 {
 648         struct device *dev;
 649
 650         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 651                                 match_orphan);
 652
 653         return dev ? to_ccwdev(dev) : NULL;
 654 }
 655
 656 static void
 657 ccw_device_add_changed(struct work_struct *work)
 658 {
 659         struct ccw_device_private *priv;
 660         struct ccw_device *cdev;
 661
 662         priv = container_of(work, struct ccw_device_private, kick_work);
 663         cdev = priv->cdev;
 664         if (device_add(&cdev->dev)) {
 665                 put_device(&cdev->dev);
 666                 return;
 667         }
 668         set_bit(1, &cdev->private->registered);
 669 }
 670
 671 void ccw_device_do_unreg_rereg(struct work_struct *work)
 672 {
 673         struct ccw_device_private *priv;
 674         struct ccw_device *cdev;
 675         struct subchannel *sch;
 676
 677         priv = container_of(work, struct ccw_device_private, kick_work);
 678         cdev = priv->cdev;
 679         sch = to_subchannel(cdev->dev.parent);
 680
 681         ccw_device_unregister(cdev);
 682         PREPARE_WORK(&cdev->private->kick_work,
 683                      ccw_device_add_changed);
 684         queue_work(ccw_device_work, &cdev->private->kick_work);
 685 }
 686
 687 static void
 688 ccw_device_release(struct device *dev)
 689 {
 690         struct ccw_device *cdev;
 691
 692         cdev = to_ccwdev(dev);
 693         kfree(cdev->private);
 694         kfree(cdev);
 695 }
 696
 697 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 698 {
 699         struct ccw_device *cdev;
 700
 701         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 702         if (cdev) {
 703                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 704                                         GFP_KERNEL | GFP_DMA);
 705                 if (cdev->private)
 706                         return cdev;
 707         }
 708         kfree(cdev);
 709         return ERR_PTR(-ENOMEM);
 710 }
 711
 712 static int io_subchannel_initialize_dev(struct subchannel *sch,
 713                                         struct ccw_device *cdev)
 714 {
 715         cdev->private->cdev = cdev;
 716         atomic_set(&cdev->private->onoff, 0);
 717         cdev->dev.parent = &sch->dev;
 718         cdev->dev.release = ccw_device_release;
 719         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
 720         cdev->dev.groups = ccwdev_attr_groups;
 721         /* Do first half of device_register. */
 722         device_initialize(&cdev->dev);
 723         if (!get_device(&sch->dev)) {
 724                 if (cdev->dev.release)
 725                         cdev->dev.release(&cdev->dev);
 726                 return -ENODEV;
 727         }
 728         return 0;
 729 }
 730
 731 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 732 {
 733         struct ccw_device *cdev;
 734         int ret;
 735
 736         cdev = io_subchannel_allocate_dev(sch);
 737         if (!IS_ERR(cdev)) {
 738                 ret = io_subchannel_initialize_dev(sch, cdev);
 739                 if (ret) {
 740                         kfree(cdev);
 741                         cdev = ERR_PTR(ret);
 742                 }
 743         }
 744         return cdev;
 745 }
 746
 747 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 748
 749 static void sch_attach_device(struct subchannel *sch,
 750                               struct ccw_device *cdev)
 751 {
 752         css_update_ssd_info(sch);
 753         spin_lock_irq(sch->lock);
 754         sch->dev.driver_data = cdev;
 755         cdev->private->schid = sch->schid;
 756         cdev->ccwlock = sch->lock;
 757         device_trigger_reprobe(sch);
 758         spin_unlock_irq(sch->lock);
 759 }
 760
 761 static void sch_attach_disconnected_device(struct subchannel *sch,
 762                                            struct ccw_device *cdev)
 763 {
 764         struct subchannel *other_sch;
 765         int ret;
 766
 767         other_sch = to_subchannel(get_device(cdev->dev.parent));
 768         ret = device_move(&cdev->dev, &sch->dev);
 769         if (ret) {
 770                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
 771                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 772                               cdev->private->dev_id.devno, ret);
 773                 put_device(&other_sch->dev);
 774                 return;
 775         }
 776         other_sch->dev.driver_data = NULL;
 777         /* No need to keep a subchannel without ccw device around. */
 778         css_sch_device_unregister(other_sch);
 779         put_device(&other_sch->dev);
 780         sch_attach_device(sch, cdev);
 781 }
 782
 783 static void sch_attach_orphaned_device(struct subchannel *sch,
 784                                        struct ccw_device *cdev)
 785 {
 786         int ret;
 787
 788         /* Try to move the ccw device to its new subchannel. */
 789         ret = device_move(&cdev->dev, &sch->dev);
 790         if (ret) {
 791                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 792                               "failed (ret=%d)!\n",
 793                               cdev->private->dev_id.ssid,
 794                               cdev->private->dev_id.devno, ret);
 795                 return;
 796         }
 797         sch_attach_device(sch, cdev);
 798 }
 799
 800 static void sch_create_and_recog_new_device(struct subchannel *sch)
 801 {
 802         struct ccw_device *cdev;
 803
 804         /* Need to allocate a new ccw device. */
 805         cdev = io_subchannel_create_ccwdev(sch);
 806         if (IS_ERR(cdev)) {
 807                 /* OK, we did everything we could... */
 808                 css_sch_device_unregister(sch);
 809                 return;
 810         }
 811         spin_lock_irq(sch->lock);
 812         sch->dev.driver_data = cdev;
 813         spin_unlock_irq(sch->lock);
 814         /* Start recognition for the new ccw device. */
 815         if (io_subchannel_recog(cdev, sch)) {
 816                 spin_lock_irq(sch->lock);
 817                 sch->dev.driver_data = NULL;
 818                 spin_unlock_irq(sch->lock);
 819                 if (cdev->dev.release)
 820                         cdev->dev.release(&cdev->dev);
 821                 css_sch_device_unregister(sch);
 822         }
 823 }
 824
 825
 826 void ccw_device_move_to_orphanage(struct work_struct *work)
 827 {
 828         struct ccw_device_private *priv;
 829         struct ccw_device *cdev;
 830         struct ccw_device *replacing_cdev;
 831         struct subchannel *sch;
 832         int ret;
 833         struct channel_subsystem *css;
 834         struct ccw_dev_id dev_id;
 835
 836         priv = container_of(work, struct ccw_device_private, kick_work);
 837         cdev = priv->cdev;
 838         sch = to_subchannel(cdev->dev.parent);
 839         css = to_css(sch->dev.parent);
 840         dev_id.devno = sch->schib.pmcw.dev;
 841         dev_id.ssid = sch->schid.ssid;
 842
 843         /*
 844          * Move the orphaned ccw device to the orphanage so the replacing
 845          * ccw device can take its place on the subchannel.
 846          */
 847         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 848         if (ret) {
 849                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 850                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 851                               cdev->private->dev_id.devno, ret);
 852                 return;
 853         }
 854         cdev->ccwlock = css->pseudo_subchannel->lock;
 855         /*
 856          * Search for the replacing ccw device
 857          * - among the disconnected devices
 858          * - in the orphanage
 859          */
 860         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 861         if (replacing_cdev) {
 862                 sch_attach_disconnected_device(sch, replacing_cdev);
 863                 return;
 864         }
 865         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 866         if (replacing_cdev) {
 867                 sch_attach_orphaned_device(sch, replacing_cdev);
 868                 return;
 869         }
 870         sch_create_and_recog_new_device(sch);
 871 }
 872
 873 /*
 874  * Register recognized device.
 875  */
 876 static void
 877 io_subchannel_register(struct work_struct *work)
 878 {
 879         struct ccw_device_private *priv;
 880         struct ccw_device *cdev;
 881         struct subchannel *sch;
 882         int ret;
 883         unsigned long flags;
 884
 885         priv = container_of(work, struct ccw_device_private, kick_work);
 886         cdev = priv->cdev;
 887         sch = to_subchannel(cdev->dev.parent);
 888         css_update_ssd_info(sch);
 889         /*
 890          * io_subchannel_register() will also be called after device
 891          * recognition has been done for a boxed device (which will already
 892          * be registered). We need to reprobe since we may now have sense id
 893          * information.
 894          */
 895         if (klist_node_attached(&cdev->dev.knode_parent)) {
 896                 if (!cdev->drv) {
 897                         ret = device_reprobe(&cdev->dev);
 898                         if (ret)
 899                                 /* We can't do much here. */
 900                                 CIO_MSG_EVENT(2, "device_reprobe() returned"
 901                                               " %d for 0.%x.%04x\n", ret,
 902                                               cdev->private->dev_id.ssid,
 903                                               cdev->private->dev_id.devno);
 904                 }
 905                 goto out;
 906         }
 907         /*
 908          * Now we know this subchannel will stay, we can throw
 909          * our delayed uevent.
 910          */
 911         sch->dev.uevent_suppress = 0;
 912         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 913         /* make it known to the system */
 914         ret = ccw_device_register(cdev);
 915         if (ret) {
 916                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 917                               cdev->private->dev_id.ssid,
 918                               cdev->private->dev_id.devno, ret);
 919                 put_device(&cdev->dev);
 920                 spin_lock_irqsave(sch->lock, flags);
 921                 sch->dev.driver_data = NULL;
 922                 spin_unlock_irqrestore(sch->lock, flags);
 923                 kfree (cdev->private);
 924                 kfree (cdev);
 925                 put_device(&sch->dev);
 926                 if (atomic_dec_and_test(&ccw_device_init_count))
 927                         wake_up(&ccw_device_init_wq);
 928                 return;
 929         }
 930         put_device(&cdev->dev);
 931 out:
 932         cdev->private->flags.recog_done = 1;
 933         put_device(&sch->dev);
 934         wake_up(&cdev->private->wait_q);
 935         if (atomic_dec_and_test(&ccw_device_init_count))
 936                 wake_up(&ccw_device_init_wq);
 937 }
 938
 939 void
 940 ccw_device_call_sch_unregister(struct work_struct *work)
 941 {
 942         struct ccw_device_private *priv;
 943         struct ccw_device *cdev;
 944         struct subchannel *sch;
 945
 946         priv = container_of(work, struct ccw_device_private, kick_work);
 947         cdev = priv->cdev;
 948         sch = to_subchannel(cdev->dev.parent);
 949         css_sch_device_unregister(sch);
 950         /* Reset intparm to zeroes. */
 951         sch->schib.pmcw.intparm = 0;
 952         cio_modify(sch);
 953         put_device(&cdev->dev);
 954         put_device(&sch->dev);
 955 }
 956
 957 /*
 958  * subchannel recognition done. Called from the state machine.
 959  */
 960 void
 961 io_subchannel_recog_done(struct ccw_device *cdev)
 962 {
 963         struct subchannel *sch;
 964
 965         if (css_init_done == 0) {
 966                 cdev->private->flags.recog_done = 1;
 967                 return;
 968         }
 969         switch (cdev->private->state) {
 970         case DEV_STATE_NOT_OPER:
 971                 cdev->private->flags.recog_done = 1;
 972                 /* Remove device found not operational. */
 973                 if (!get_device(&cdev->dev))
 974                         break;
 975                 sch = to_subchannel(cdev->dev.parent);
 976                 PREPARE_WORK(&cdev->private->kick_work,
 977                              ccw_device_call_sch_unregister);
 978                 queue_work(slow_path_wq, &cdev->private->kick_work);
 979                 if (atomic_dec_and_test(&ccw_device_init_count))
 980                         wake_up(&ccw_device_init_wq);
 981                 break;
 982         case DEV_STATE_BOXED:
 983                 /* Device did not respond in time. */
 984         case DEV_STATE_OFFLINE:
 985                 /*
 986                  * We can't register the device in interrupt context so
 987                  * we schedule a work item.
 988                  */
 989                 if (!get_device(&cdev->dev))
 990                         break;
 991                 PREPARE_WORK(&cdev->private->kick_work,
 992                              io_subchannel_register);
 993                 queue_work(slow_path_wq, &cdev->private->kick_work);
 994                 break;
 995         }
 996 }
 997
 998 static int
 999 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1000 {
1001         int rc;
1002         struct ccw_device_private *priv;
1003
1004         sch->dev.driver_data = cdev;
1005         sch->driver = &io_subchannel_driver;
1006         cdev->ccwlock = sch->lock;
1007
1008         /* Init private data. */
1009         priv = cdev->private;
1010         priv->dev_id.devno = sch->schib.pmcw.dev;
1011         priv->dev_id.ssid = sch->schid.ssid;
1012         priv->schid = sch->schid;
1013         priv->state = DEV_STATE_NOT_OPER;
1014         INIT_LIST_HEAD(&priv->cmb_list);
1015         init_waitqueue_head(&priv->wait_q);
1016         init_timer(&priv->timer);
1017
1018         /* Set an initial name for the device. */
1019         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1020                   sch->schid.ssid, sch->schib.pmcw.dev);
1021
1022         /* Increase counter of devices currently in recognition. */
1023         atomic_inc(&ccw_device_init_count);
1024
1025         /* Start async. device sensing. */
1026         spin_lock_irq(sch->lock);
1027         rc = ccw_device_recognition(cdev);
1028         spin_unlock_irq(sch->lock);
1029         if (rc) {
1030                 if (atomic_dec_and_test(&ccw_device_init_count))
1031                         wake_up(&ccw_device_init_wq);
1032         }
1033         return rc;
1034 }
1035
1036 static void ccw_device_move_to_sch(struct work_struct *work)
1037 {
1038         struct ccw_device_private *priv;
1039         int rc;
1040         struct subchannel *sch;
1041         struct ccw_device *cdev;
1042         struct subchannel *former_parent;
1043
1044         priv = container_of(work, struct ccw_device_private, kick_work);
1045         sch = priv->sch;
1046         cdev = priv->cdev;
1047         former_parent = ccw_device_is_orphan(cdev) ?
1048                 NULL : to_subchannel(get_device(cdev->dev.parent));
1049         mutex_lock(&sch->reg_mutex);
1050         /* Try to move the ccw device to its new subchannel. */
1051         rc = device_move(&cdev->dev, &sch->dev);
1052         mutex_unlock(&sch->reg_mutex);
1053         if (rc) {
1054                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1055                               "0.%x.%04x failed (ret=%d)!\n",
1056                               cdev->private->dev_id.ssid,
1057                               cdev->private->dev_id.devno, sch->schid.ssid,
1058                               sch->schid.sch_no, rc);
1059                 css_sch_device_unregister(sch);
1060                 goto out;
1061         }
1062         if (former_parent) {
1063                 spin_lock_irq(former_parent->lock);
1064                 former_parent->dev.driver_data = NULL;
1065                 spin_unlock_irq(former_parent->lock);
1066                 css_sch_device_unregister(former_parent);
1067                 /* Reset intparm to zeroes. */
1068                 former_parent->schib.pmcw.intparm = 0;
1069                 cio_modify(former_parent);
1070         }
1071         sch_attach_device(sch, cdev);
1072 out:
1073         if (former_parent)
1074                 put_device(&former_parent->dev);
1075         put_device(&cdev->dev);
1076 }
1077
1078 static int
1079 io_subchannel_probe (struct subchannel *sch)
1080 {
1081         struct ccw_device *cdev;
1082         int rc;
1083         unsigned long flags;
1084         struct ccw_dev_id dev_id;
1085
1086         if (sch->dev.driver_data) {
1087                 /*
1088                  * This subchannel already has an associated ccw_device.
1089                  * Register it and exit. This happens for all early
1090                  * device, e.g. the console.
1091                  */
1092                 cdev = sch->dev.driver_data;
1093                 device_initialize(&cdev->dev);
1094                 ccw_device_register(cdev);
1095                 /*
1096                  * Check if the device is already online. If it is
1097                  * the reference count needs to be corrected
1098                  * (see ccw_device_online and css_init_done for the
1099                  * ugly details).
1100                  */
1101                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1102                     cdev->private->state != DEV_STATE_OFFLINE &&
1103                     cdev->private->state != DEV_STATE_BOXED)
1104                         get_device(&cdev->dev);
1105                 return 0;
1106         }
1107         /*
1108          * First check if a fitting device may be found amongst the
1109          * disconnected devices or in the orphanage.
1110          */
1111         dev_id.devno = sch->schib.pmcw.dev;
1112         dev_id.ssid = sch->schid.ssid;
1113         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1114         if (!cdev)
1115                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1116                                                      &dev_id);
1117         if (cdev) {
1118                 /*
1119                  * Schedule moving the device until when we have a registered
1120                  * subchannel to move to and succeed the probe. We can
1121                  * unregister later again, when the probe is through.
1122                  */
1123                 cdev->private->sch = sch;
1124                 PREPARE_WORK(&cdev->private->kick_work,
1125                              ccw_device_move_to_sch);
1126                 queue_work(slow_path_wq, &cdev->private->kick_work);
1127                 return 0;
1128         }
1129         cdev = io_subchannel_create_ccwdev(sch);
1130         if (IS_ERR(cdev))
1131                 return PTR_ERR(cdev);
1132
1133         rc = io_subchannel_recog(cdev, sch);
1134         if (rc) {
1135                 spin_lock_irqsave(sch->lock, flags);
1136                 sch->dev.driver_data = NULL;
1137                 spin_unlock_irqrestore(sch->lock, flags);
1138                 if (cdev->dev.release)
1139                         cdev->dev.release(&cdev->dev);
1140         }
1141
1142         return rc;
1143 }
1144
1145 static int
1146 io_subchannel_remove (struct subchannel *sch)
1147 {
1148         struct ccw_device *cdev;
1149         unsigned long flags;
1150
1151         if (!sch->dev.driver_data)
1152                 return 0;
1153         cdev = sch->dev.driver_data;
1154         /* Set ccw device to not operational and drop reference. */
1155         spin_lock_irqsave(cdev->ccwlock, flags);
1156         sch->dev.driver_data = NULL;
1157         cdev->private->state = DEV_STATE_NOT_OPER;
1158         spin_unlock_irqrestore(cdev->ccwlock, flags);
1159         ccw_device_unregister(cdev);
1160         put_device(&cdev->dev);
1161         return 0;
1162 }
1163
1164 static int
1165 io_subchannel_notify(struct device *dev, int event)
1166 {
1167         struct ccw_device *cdev;
1168
1169         cdev = dev->driver_data;
1170         if (!cdev)
1171                 return 0;
1172         if (!cdev->drv)
1173                 return 0;
1174         if (!cdev->online)
1175                 return 0;
1176         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1177 }
1178
1179 static void
1180 io_subchannel_verify(struct device *dev)
1181 {
1182         struct ccw_device *cdev;
1183
1184         cdev = dev->driver_data;
1185         if (cdev)
1186                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1187 }
1188
1189 static void
1190 io_subchannel_ioterm(struct device *dev)
1191 {
1192         struct ccw_device *cdev;
1193
1194         cdev = dev->driver_data;
1195         if (!cdev)
1196                 return;
1197         /* Internal I/O will be retried by the interrupt handler. */
1198         if (cdev->private->flags.intretry)
1199                 return;
1200         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1201         if (cdev->handler)
1202                 cdev->handler(cdev, cdev->private->intparm,
1203                               ERR_PTR(-EIO));
1204 }
1205
1206 static void
1207 io_subchannel_shutdown(struct subchannel *sch)
1208 {
1209         struct ccw_device *cdev;
1210         int ret;
1211
1212         cdev = sch->dev.driver_data;
1213
1214         if (cio_is_console(sch->schid))
1215                 return;
1216         if (!sch->schib.pmcw.ena)
1217                 /* Nothing to do. */
1218                 return;
1219         ret = cio_disable_subchannel(sch);
1220         if (ret != -EBUSY)
1221                 /* Subchannel is disabled, we're done. */
1222                 return;
1223         cdev->private->state = DEV_STATE_QUIESCE;
1224         if (cdev->handler)
1225                 cdev->handler(cdev, cdev->private->intparm,
1226                               ERR_PTR(-EIO));
1227         ret = ccw_device_cancel_halt_clear(cdev);
1228         if (ret == -EBUSY) {
1229                 ccw_device_set_timeout(cdev, HZ/10);
1230                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1231         }
1232         cio_disable_subchannel(sch);
1233 }
1234
1235 #ifdef CONFIG_CCW_CONSOLE
1236 static struct ccw_device console_cdev;
1237 static struct ccw_device_private console_private;
1238 static int console_cdev_in_use;
1239
1240 static DEFINE_SPINLOCK(ccw_console_lock);
1241
1242 spinlock_t * cio_get_console_lock(void)
1243 {
1244         return &ccw_console_lock;
1245 }
1246
1247 static int
1248 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1249 {
1250         int rc;
1251
1252         /* Initialize the ccw_device structure. */
1253         cdev->dev.parent= &sch->dev;
1254         rc = io_subchannel_recog(cdev, sch);
1255         if (rc)
1256                 return rc;
1257
1258         /* Now wait for the async. recognition to come to an end. */
1259         spin_lock_irq(cdev->ccwlock);
1260         while (!dev_fsm_final_state(cdev))
1261                 wait_cons_dev();
1262         rc = -EIO;
1263         if (cdev->private->state != DEV_STATE_OFFLINE)
1264                 goto out_unlock;
1265         ccw_device_online(cdev);
1266         while (!dev_fsm_final_state(cdev))
1267                 wait_cons_dev();
1268         if (cdev->private->state != DEV_STATE_ONLINE)
1269                 goto out_unlock;
1270         rc = 0;
1271 out_unlock:
1272         spin_unlock_irq(cdev->ccwlock);
1273         return 0;
1274 }
1275
1276 struct ccw_device *
1277 ccw_device_probe_console(void)
1278 {
1279         struct subchannel *sch;
1280         int ret;
1281
1282         if (xchg(&console_cdev_in_use, 1) != 0)
1283                 return ERR_PTR(-EBUSY);
1284         sch = cio_probe_console();
1285         if (IS_ERR(sch)) {
1286                 console_cdev_in_use = 0;
1287                 return (void *) sch;
1288         }
1289         memset(&console_cdev, 0, sizeof(struct ccw_device));
1290         memset(&console_private, 0, sizeof(struct ccw_device_private));
1291         console_cdev.private = &console_private;
1292         console_private.cdev = &console_cdev;
1293         ret = ccw_device_console_enable(&console_cdev, sch);
1294         if (ret) {
1295                 cio_release_console();
1296                 console_cdev_in_use = 0;
1297                 return ERR_PTR(ret);
1298         }
1299         console_cdev.online = 1;
1300         return &console_cdev;
1301 }
1302 #endif
1303
1304 /*
1305  * get ccw_device matching the busid, but only if owned by cdrv
1306  */
1307 static int
1308 __ccwdev_check_busid(struct device *dev, void *id)
1309 {
1310         char *bus_id;
1311
1312         bus_id = id;
1313
1314         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1315 }
1316
1317
1318 struct ccw_device *
1319 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1320 {
1321         struct device *dev;
1322         struct device_driver *drv;
1323
1324         drv = get_driver(&cdrv->driver);
1325         if (!drv)
1326                 return NULL;
1327
1328         dev = driver_find_device(drv, NULL, (void *)bus_id,
1329                                  __ccwdev_check_busid);
1330         put_driver(drv);
1331
1332         return dev ? to_ccwdev(dev) : NULL;
1333 }
1334
1335 /************************** device driver handling ************************/
1336
1337 /* This is the implementation of the ccw_driver class. The probe, remove
1338  * and release methods are initially very similar to the device_driver
1339  * implementations, with the difference that they have ccw_device
1340  * arguments.
1341  *
1342  * A ccw driver also contains the information that is needed for
1343  * device matching.
1344  */
1345 static int
1346 ccw_device_probe (struct device *dev)
1347 {
1348         struct ccw_device *cdev = to_ccwdev(dev);
1349         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1350         int ret;
1351
1352         cdev->drv = cdrv; /* to let the driver call _set_online */
1353
1354         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1355
1356         if (ret) {
1357                 cdev->drv = NULL;
1358                 return ret;
1359         }
1360
1361         return 0;
1362 }
1363
1364 static int
1365 ccw_device_remove (struct device *dev)
1366 {
1367         struct ccw_device *cdev = to_ccwdev(dev);
1368         struct ccw_driver *cdrv = cdev->drv;
1369         int ret;
1370
1371         if (cdrv->remove)
1372                 cdrv->remove(cdev);
1373         if (cdev->online) {
1374                 cdev->online = 0;
1375                 spin_lock_irq(cdev->ccwlock);
1376                 ret = ccw_device_offline(cdev);
1377                 spin_unlock_irq(cdev->ccwlock);
1378                 if (ret == 0)
1379                         wait_event(cdev->private->wait_q,
1380                                    dev_fsm_final_state(cdev));
1381                 else
1382                         //FIXME: we can't fail!
1383                         CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1384                                       "device 0.%x.%04x\n",
1385                                       ret, cdev->private->dev_id.ssid,
1386                                       cdev->private->dev_id.devno);
1387         }
1388         ccw_device_set_timeout(cdev, 0);
1389         cdev->drv = NULL;
1390         return 0;
1391 }
1392
1393 struct bus_type ccw_bus_type = {
1394         .name   = "ccw",
1395         .match  = ccw_bus_match,
1396         .uevent = ccw_uevent,
1397         .probe  = ccw_device_probe,
1398         .remove = ccw_device_remove,
1399 };
1400
1401 int
1402 ccw_driver_register (struct ccw_driver *cdriver)
1403 {
1404         struct device_driver *drv = &cdriver->driver;
1405
1406         drv->bus = &ccw_bus_type;
1407         drv->name = cdriver->name;
1408
1409         return driver_register(drv);
1410 }
1411
1412 void
1413 ccw_driver_unregister (struct ccw_driver *cdriver)
1414 {
1415         driver_unregister(&cdriver->driver);
1416 }
1417
1418 /* Helper func for qdio. */
1419 struct subchannel_id
1420 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1421 {
1422         struct subchannel *sch;
1423
1424         sch = to_subchannel(cdev->dev.parent);
1425         return sch->schid;
1426 }
1427
1428 MODULE_LICENSE("GPL");
1429 EXPORT_SYMBOL(ccw_device_set_online);
1430 EXPORT_SYMBOL(ccw_device_set_offline);
1431 EXPORT_SYMBOL(ccw_driver_register);
1432 EXPORT_SYMBOL(ccw_driver_unregister);
1433 EXPORT_SYMBOL(get_ccwdev_by_busid);
1434 EXPORT_SYMBOL(ccw_bus_type);
1435 EXPORT_SYMBOL(ccw_device_work);
1436 EXPORT_SYMBOL(ccw_device_notify_work);
1437 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);