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 #include <linux/timer.h>
  21
  22 #include <asm/ccwdev.h>
  23 #include <asm/cio.h>
  24 #include <asm/param.h>          /* HZ */
  25 #include <asm/cmb.h>
  26
  27 #include "cio.h"
  28 #include "cio_debug.h"
  29 #include "css.h"
  30 #include "device.h"
  31 #include "ioasm.h"
  32 #include "io_sch.h"
  33
  34 static struct timer_list recovery_timer;
  35 static DEFINE_SPINLOCK(recovery_lock);
  36 static int recovery_phase;
  37 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  38
  39 /******************* bus type handling ***********************/
  40
  41 /* The Linux driver model distinguishes between a bus type and
  42  * the bus itself. Of course we only have one channel
  43  * subsystem driver and one channel system per machine, but
  44  * we still use the abstraction. T.R. says it's a good idea. */
  45 static int
  46 ccw_bus_match (struct device * dev, struct device_driver * drv)
  47 {
  48         struct ccw_device *cdev = to_ccwdev(dev);
  49         struct ccw_driver *cdrv = to_ccwdrv(drv);
  50         const struct ccw_device_id *ids = cdrv->ids, *found;
  51
  52         if (!ids)
  53                 return 0;
  54
  55         found = ccw_device_id_match(ids, &cdev->id);
  56         if (!found)
  57                 return 0;
  58
  59         cdev->id.driver_info = found->driver_info;
  60
  61         return 1;
  62 }
  63
  64 /* Store modalias string delimited by prefix/suffix string into buffer with
  65  * specified size. Return length of resulting string (excluding trailing '\0')
  66  * even if string doesn't fit buffer (snprintf semantics). */
  67 static int snprint_alias(char *buf, size_t size,
  68                          struct ccw_device_id *id, const char *suffix)
  69 {
  70         int len;
  71
  72         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  73         if (len > size)
  74                 return len;
  75         buf += len;
  76         size -= len;
  77
  78         if (id->dev_type != 0)
  79                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  80                                 id->dev_model, suffix);
  81         else
  82                 len += snprintf(buf, size, "dtdm%s", suffix);
  83
  84         return len;
  85 }
  86
  87 /* Set up environment variables for ccw device uevent. Return 0 on success,
  88  * non-zero otherwise. */
  89 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  90 {
  91         struct ccw_device *cdev = to_ccwdev(dev);
  92         struct ccw_device_id *id = &(cdev->id);
  93         int ret;
  94         char modalias_buf[30];
  95
  96         /* CU_TYPE= */
  97         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
  98         if (ret)
  99                 return ret;
 100
 101         /* CU_MODEL= */
 102         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 103         if (ret)
 104                 return ret;
 105
 106         /* The next two can be zero, that's ok for us */
 107         /* DEV_TYPE= */
 108         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 109         if (ret)
 110                 return ret;
 111
 112         /* DEV_MODEL= */
 113         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 114         if (ret)
 115                 return ret;
 116
 117         /* MODALIAS=  */
 118         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 119         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 120         return ret;
 121 }
 122
 123 struct bus_type ccw_bus_type;
 124
 125 static void io_subchannel_irq(struct subchannel *);
 126 static int io_subchannel_probe(struct subchannel *);
 127 static int io_subchannel_remove(struct subchannel *);
 128 static int io_subchannel_notify(struct subchannel *, int);
 129 static void io_subchannel_verify(struct subchannel *);
 130 static void io_subchannel_ioterm(struct subchannel *);
 131 static void io_subchannel_shutdown(struct subchannel *);
 132
 133 static struct css_driver io_subchannel_driver = {
 134         .owner = THIS_MODULE,
 135         .subchannel_type = SUBCHANNEL_TYPE_IO,
 136         .name = "io_subchannel",
 137         .irq = io_subchannel_irq,
 138         .notify = io_subchannel_notify,
 139         .verify = io_subchannel_verify,
 140         .termination = io_subchannel_ioterm,
 141         .probe = io_subchannel_probe,
 142         .remove = io_subchannel_remove,
 143         .shutdown = io_subchannel_shutdown,
 144 };
 145
 146 struct workqueue_struct *ccw_device_work;
 147 struct workqueue_struct *ccw_device_notify_work;
 148 wait_queue_head_t ccw_device_init_wq;
 149 atomic_t ccw_device_init_count;
 150
 151 static void recovery_func(unsigned long data);
 152
 153 static int __init
 154 init_ccw_bus_type (void)
 155 {
 156         int ret;
 157
 158         init_waitqueue_head(&ccw_device_init_wq);
 159         atomic_set(&ccw_device_init_count, 0);
 160         setup_timer(&recovery_timer, recovery_func, 0);
 161
 162         ccw_device_work = create_singlethread_workqueue("cio");
 163         if (!ccw_device_work)
 164                 return -ENOMEM; /* FIXME: better errno ? */
 165         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 166         if (!ccw_device_notify_work) {
 167                 ret = -ENOMEM; /* FIXME: better errno ? */
 168                 goto out_err;
 169         }
 170         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 171         if (!slow_path_wq) {
 172                 ret = -ENOMEM; /* FIXME: better errno ? */
 173                 goto out_err;
 174         }
 175         if ((ret = bus_register (&ccw_bus_type)))
 176                 goto out_err;
 177
 178         ret = css_driver_register(&io_subchannel_driver);
 179         if (ret)
 180                 goto out_err;
 181
 182         wait_event(ccw_device_init_wq,
 183                    atomic_read(&ccw_device_init_count) == 0);
 184         flush_workqueue(ccw_device_work);
 185         return 0;
 186 out_err:
 187         if (ccw_device_work)
 188                 destroy_workqueue(ccw_device_work);
 189         if (ccw_device_notify_work)
 190                 destroy_workqueue(ccw_device_notify_work);
 191         if (slow_path_wq)
 192                 destroy_workqueue(slow_path_wq);
 193         return ret;
 194 }
 195
 196 static void __exit
 197 cleanup_ccw_bus_type (void)
 198 {
 199         css_driver_unregister(&io_subchannel_driver);
 200         bus_unregister(&ccw_bus_type);
 201         destroy_workqueue(ccw_device_notify_work);
 202         destroy_workqueue(ccw_device_work);
 203 }
 204
 205 subsys_initcall(init_ccw_bus_type);
 206 module_exit(cleanup_ccw_bus_type);
 207
 208 /************************ device handling **************************/
 209
 210 /*
 211  * A ccw_device has some interfaces in sysfs in addition to the
 212  * standard ones.
 213  * The following entries are designed to export the information which
 214  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 215  * are obvious, so they don't have an entry :)
 216  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 217  */
 218 static ssize_t
 219 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 220 {
 221         struct subchannel *sch = to_subchannel(dev);
 222         struct chsc_ssd_info *ssd = &sch->ssd_info;
 223         ssize_t ret = 0;
 224         int chp;
 225         int mask;
 226
 227         for (chp = 0; chp < 8; chp++) {
 228                 mask = 0x80 >> chp;
 229                 if (ssd->path_mask & mask)
 230                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 231                 else
 232                         ret += sprintf(buf + ret, "00 ");
 233         }
 234         ret += sprintf (buf+ret, "\n");
 235         return min((ssize_t)PAGE_SIZE, ret);
 236 }
 237
 238 static ssize_t
 239 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 240 {
 241         struct subchannel *sch = to_subchannel(dev);
 242         struct pmcw *pmcw = &sch->schib.pmcw;
 243
 244         return sprintf (buf, "%02x %02x %02x\n",
 245                         pmcw->pim, pmcw->pam, pmcw->pom);
 246 }
 247
 248 static ssize_t
 249 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 250 {
 251         struct ccw_device *cdev = to_ccwdev(dev);
 252         struct ccw_device_id *id = &(cdev->id);
 253
 254         if (id->dev_type != 0)
 255                 return sprintf(buf, "%04x/%02x\n",
 256                                 id->dev_type, id->dev_model);
 257         else
 258                 return sprintf(buf, "n/a\n");
 259 }
 260
 261 static ssize_t
 262 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 263 {
 264         struct ccw_device *cdev = to_ccwdev(dev);
 265         struct ccw_device_id *id = &(cdev->id);
 266
 267         return sprintf(buf, "%04x/%02x\n",
 268                        id->cu_type, id->cu_model);
 269 }
 270
 271 static ssize_t
 272 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 273 {
 274         struct ccw_device *cdev = to_ccwdev(dev);
 275         struct ccw_device_id *id = &(cdev->id);
 276         int len;
 277
 278         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 279
 280         return len > PAGE_SIZE ? PAGE_SIZE : len;
 281 }
 282
 283 static ssize_t
 284 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 285 {
 286         struct ccw_device *cdev = to_ccwdev(dev);
 287
 288         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 289 }
 290
 291 int ccw_device_is_orphan(struct ccw_device *cdev)
 292 {
 293         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 294 }
 295
 296 static void ccw_device_unregister(struct ccw_device *cdev)
 297 {
 298         if (test_and_clear_bit(1, &cdev->private->registered))
 299                 device_del(&cdev->dev);
 300 }
 301
 302 static void ccw_device_remove_orphan_cb(struct device *dev)
 303 {
 304         struct ccw_device *cdev = to_ccwdev(dev);
 305
 306         ccw_device_unregister(cdev);
 307         put_device(&cdev->dev);
 308 }
 309
 310 static void ccw_device_remove_sch_cb(struct device *dev)
 311 {
 312         struct subchannel *sch;
 313
 314         sch = to_subchannel(dev);
 315         css_sch_device_unregister(sch);
 316         /* Reset intparm to zeroes. */
 317         sch->schib.pmcw.intparm = 0;
 318         cio_modify(sch);
 319         put_device(&sch->dev);
 320 }
 321
 322 static void
 323 ccw_device_remove_disconnected(struct ccw_device *cdev)
 324 {
 325         unsigned long flags;
 326         int rc;
 327
 328         /*
 329          * Forced offline in disconnected state means
 330          * 'throw away device'.
 331          */
 332         if (ccw_device_is_orphan(cdev)) {
 333                 /*
 334                  * Deregister ccw device.
 335                  * Unfortunately, we cannot do this directly from the
 336                  * attribute method.
 337                  */
 338                 spin_lock_irqsave(cdev->ccwlock, flags);
 339                 cdev->private->state = DEV_STATE_NOT_OPER;
 340                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 341                 rc = device_schedule_callback(&cdev->dev,
 342                                               ccw_device_remove_orphan_cb);
 343                 if (rc)
 344                         CIO_MSG_EVENT(0, "Couldn't unregister orphan "
 345                                       "0.%x.%04x\n",
 346                                       cdev->private->dev_id.ssid,
 347                                       cdev->private->dev_id.devno);
 348                 return;
 349         }
 350         /* Deregister subchannel, which will kill the ccw device. */
 351         rc = device_schedule_callback(cdev->dev.parent,
 352                                       ccw_device_remove_sch_cb);
 353         if (rc)
 354                 CIO_MSG_EVENT(0, "Couldn't unregister disconnected device "
 355                               "0.%x.%04x\n",
 356                               cdev->private->dev_id.ssid,
 357                               cdev->private->dev_id.devno);
 358 }
 359
 360 /**
 361  * ccw_device_set_offline() - disable a ccw device for I/O
 362  * @cdev: target ccw device
 363  *
 364  * This function calls the driver's set_offline() function for @cdev, if
 365  * given, and then disables @cdev.
 366  * Returns:
 367  *   %0 on success and a negative error value on failure.
 368  * Context:
 369  *  enabled, ccw device lock not held
 370  */
 371 int ccw_device_set_offline(struct ccw_device *cdev)
 372 {
 373         int ret;
 374
 375         if (!cdev)
 376                 return -ENODEV;
 377         if (!cdev->online || !cdev->drv)
 378                 return -EINVAL;
 379
 380         if (cdev->drv->set_offline) {
 381                 ret = cdev->drv->set_offline(cdev);
 382                 if (ret != 0)
 383                         return ret;
 384         }
 385         cdev->online = 0;
 386         spin_lock_irq(cdev->ccwlock);
 387         ret = ccw_device_offline(cdev);
 388         if (ret == -ENODEV) {
 389                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 390                         cdev->private->state = DEV_STATE_OFFLINE;
 391                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 392                 }
 393                 spin_unlock_irq(cdev->ccwlock);
 394                 return ret;
 395         }
 396         spin_unlock_irq(cdev->ccwlock);
 397         if (ret == 0)
 398                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 399         else {
 400                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
 401                               "device 0.%x.%04x\n",
 402                               ret, cdev->private->dev_id.ssid,
 403                               cdev->private->dev_id.devno);
 404                 cdev->online = 1;
 405         }
 406         return ret;
 407 }
 408
 409 /**
 410  * ccw_device_set_online() - enable a ccw device for I/O
 411  * @cdev: target ccw device
 412  *
 413  * This function first enables @cdev and then calls the driver's set_online()
 414  * function for @cdev, if given. If set_online() returns an error, @cdev is
 415  * disabled again.
 416  * Returns:
 417  *   %0 on success and a negative error value on failure.
 418  * Context:
 419  *  enabled, ccw device lock not held
 420  */
 421 int ccw_device_set_online(struct ccw_device *cdev)
 422 {
 423         int ret;
 424
 425         if (!cdev)
 426                 return -ENODEV;
 427         if (cdev->online || !cdev->drv)
 428                 return -EINVAL;
 429
 430         spin_lock_irq(cdev->ccwlock);
 431         ret = ccw_device_online(cdev);
 432         spin_unlock_irq(cdev->ccwlock);
 433         if (ret == 0)
 434                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 435         else {
 436                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 437                               "device 0.%x.%04x\n",
 438                               ret, cdev->private->dev_id.ssid,
 439                               cdev->private->dev_id.devno);
 440                 return ret;
 441         }
 442         if (cdev->private->state != DEV_STATE_ONLINE)
 443                 return -ENODEV;
 444         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 445                 cdev->online = 1;
 446                 return 0;
 447         }
 448         spin_lock_irq(cdev->ccwlock);
 449         ret = ccw_device_offline(cdev);
 450         spin_unlock_irq(cdev->ccwlock);
 451         if (ret == 0)
 452                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 453         else
 454                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
 455                               "device 0.%x.%04x\n",
 456                               ret, cdev->private->dev_id.ssid,
 457                               cdev->private->dev_id.devno);
 458         return (ret == 0) ? -ENODEV : ret;
 459 }
 460
 461 static void online_store_handle_offline(struct ccw_device *cdev)
 462 {
 463         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 464                 ccw_device_remove_disconnected(cdev);
 465         else if (cdev->drv && cdev->drv->set_offline)
 466                 ccw_device_set_offline(cdev);
 467 }
 468
 469 static int online_store_recog_and_online(struct ccw_device *cdev)
 470 {
 471         int ret;
 472
 473         /* Do device recognition, if needed. */
 474         if (cdev->id.cu_type == 0) {
 475                 ret = ccw_device_recognition(cdev);
 476                 if (ret) {
 477                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 478                                       "for device 0.%x.%04x (ret=%d)\n",
 479                                       cdev->private->dev_id.ssid,
 480                                       cdev->private->dev_id.devno, ret);
 481                         return ret;
 482                 }
 483                 wait_event(cdev->private->wait_q,
 484                            cdev->private->flags.recog_done);
 485         }
 486         if (cdev->drv && cdev->drv->set_online)
 487                 ccw_device_set_online(cdev);
 488         return 0;
 489 }
 490 static void online_store_handle_online(struct ccw_device *cdev, int force)
 491 {
 492         int ret;
 493
 494         ret = online_store_recog_and_online(cdev);
 495         if (ret)
 496                 return;
 497         if (force && cdev->private->state == DEV_STATE_BOXED) {
 498                 ret = ccw_device_stlck(cdev);
 499                 if (ret) {
 500                         dev_warn(&cdev->dev,
 501                                  "ccw_device_stlck returned %d!\n", ret);
 502                         return;
 503                 }
 504                 if (cdev->id.cu_type == 0)
 505                         cdev->private->state = DEV_STATE_NOT_OPER;
 506                 online_store_recog_and_online(cdev);
 507         }
 508
 509 }
 510
 511 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 512                              const char *buf, size_t count)
 513 {
 514         struct ccw_device *cdev = to_ccwdev(dev);
 515         int force, ret;
 516         unsigned long i;
 517
 518         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 519                 return -EAGAIN;
 520
 521         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 522                 atomic_set(&cdev->private->onoff, 0);
 523                 return -EINVAL;
 524         }
 525         if (!strncmp(buf, "force\n", count)) {
 526                 force = 1;
 527                 i = 1;
 528                 ret = 0;
 529         } else {
 530                 force = 0;
 531                 ret = strict_strtoul(buf, 16, &i);
 532         }
 533         if (ret)
 534                 goto out;
 535         switch (i) {
 536         case 0:
 537                 online_store_handle_offline(cdev);
 538                 ret = count;
 539                 break;
 540         case 1:
 541                 online_store_handle_online(cdev, force);
 542                 ret = count;
 543                 break;
 544         default:
 545                 ret = -EINVAL;
 546         }
 547 out:
 548         if (cdev->drv)
 549                 module_put(cdev->drv->owner);
 550         atomic_set(&cdev->private->onoff, 0);
 551         return ret;
 552 }
 553
 554 static ssize_t
 555 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 556 {
 557         struct ccw_device *cdev = to_ccwdev(dev);
 558         struct subchannel *sch;
 559
 560         if (ccw_device_is_orphan(cdev))
 561                 return sprintf(buf, "no device\n");
 562         switch (cdev->private->state) {
 563         case DEV_STATE_BOXED:
 564                 return sprintf(buf, "boxed\n");
 565         case DEV_STATE_DISCONNECTED:
 566         case DEV_STATE_DISCONNECTED_SENSE_ID:
 567         case DEV_STATE_NOT_OPER:
 568                 sch = to_subchannel(dev->parent);
 569                 if (!sch->lpm)
 570                         return sprintf(buf, "no path\n");
 571                 else
 572                         return sprintf(buf, "no device\n");
 573         default:
 574                 /* All other states considered fine. */
 575                 return sprintf(buf, "good\n");
 576         }
 577 }
 578
 579 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 580 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 581 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 582 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 583 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 584 static DEVICE_ATTR(online, 0644, online_show, online_store);
 585 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 586
 587 static struct attribute * subch_attrs[] = {
 588         &dev_attr_chpids.attr,
 589         &dev_attr_pimpampom.attr,
 590         NULL,
 591 };
 592
 593 static struct attribute_group subch_attr_group = {
 594         .attrs = subch_attrs,
 595 };
 596
 597 struct attribute_group *subch_attr_groups[] = {
 598         &subch_attr_group,
 599         NULL,
 600 };
 601
 602 static struct attribute * ccwdev_attrs[] = {
 603         &dev_attr_devtype.attr,
 604         &dev_attr_cutype.attr,
 605         &dev_attr_modalias.attr,
 606         &dev_attr_online.attr,
 607         &dev_attr_cmb_enable.attr,
 608         &dev_attr_availability.attr,
 609         NULL,
 610 };
 611
 612 static struct attribute_group ccwdev_attr_group = {
 613         .attrs = ccwdev_attrs,
 614 };
 615
 616 static struct attribute_group *ccwdev_attr_groups[] = {
 617         &ccwdev_attr_group,
 618         NULL,
 619 };
 620
 621 /* this is a simple abstraction for device_register that sets the
 622  * correct bus type and adds the bus specific files */
 623 static int ccw_device_register(struct ccw_device *cdev)
 624 {
 625         struct device *dev = &cdev->dev;
 626         int ret;
 627
 628         dev->bus = &ccw_bus_type;
 629
 630         if ((ret = device_add(dev)))
 631                 return ret;
 632
 633         set_bit(1, &cdev->private->registered);
 634         return ret;
 635 }
 636
 637 struct match_data {
 638         struct ccw_dev_id dev_id;
 639         struct ccw_device * sibling;
 640 };
 641
 642 static int
 643 match_devno(struct device * dev, void * data)
 644 {
 645         struct match_data * d = data;
 646         struct ccw_device * cdev;
 647
 648         cdev = to_ccwdev(dev);
 649         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 650             !ccw_device_is_orphan(cdev) &&
 651             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 652             (cdev != d->sibling))
 653                 return 1;
 654         return 0;
 655 }
 656
 657 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 658                                                      struct ccw_device *sibling)
 659 {
 660         struct device *dev;
 661         struct match_data data;
 662
 663         data.dev_id = *dev_id;
 664         data.sibling = sibling;
 665         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 666
 667         return dev ? to_ccwdev(dev) : NULL;
 668 }
 669
 670 static int match_orphan(struct device *dev, void *data)
 671 {
 672         struct ccw_dev_id *dev_id;
 673         struct ccw_device *cdev;
 674
 675         dev_id = data;
 676         cdev = to_ccwdev(dev);
 677         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 678 }
 679
 680 static struct ccw_device *
 681 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 682                               struct ccw_dev_id *dev_id)
 683 {
 684         struct device *dev;
 685
 686         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 687                                 match_orphan);
 688
 689         return dev ? to_ccwdev(dev) : NULL;
 690 }
 691
 692 static void
 693 ccw_device_add_changed(struct work_struct *work)
 694 {
 695         struct ccw_device_private *priv;
 696         struct ccw_device *cdev;
 697
 698         priv = container_of(work, struct ccw_device_private, kick_work);
 699         cdev = priv->cdev;
 700         if (device_add(&cdev->dev)) {
 701                 put_device(&cdev->dev);
 702                 return;
 703         }
 704         set_bit(1, &cdev->private->registered);
 705 }
 706
 707 void ccw_device_do_unreg_rereg(struct work_struct *work)
 708 {
 709         struct ccw_device_private *priv;
 710         struct ccw_device *cdev;
 711         struct subchannel *sch;
 712
 713         priv = container_of(work, struct ccw_device_private, kick_work);
 714         cdev = priv->cdev;
 715         sch = to_subchannel(cdev->dev.parent);
 716
 717         ccw_device_unregister(cdev);
 718         PREPARE_WORK(&cdev->private->kick_work,
 719                      ccw_device_add_changed);
 720         queue_work(ccw_device_work, &cdev->private->kick_work);
 721 }
 722
 723 static void
 724 ccw_device_release(struct device *dev)
 725 {
 726         struct ccw_device *cdev;
 727
 728         cdev = to_ccwdev(dev);
 729         kfree(cdev->private);
 730         kfree(cdev);
 731 }
 732
 733 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 734 {
 735         struct ccw_device *cdev;
 736
 737         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 738         if (cdev) {
 739                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 740                                         GFP_KERNEL | GFP_DMA);
 741                 if (cdev->private)
 742                         return cdev;
 743         }
 744         kfree(cdev);
 745         return ERR_PTR(-ENOMEM);
 746 }
 747
 748 static int io_subchannel_initialize_dev(struct subchannel *sch,
 749                                         struct ccw_device *cdev)
 750 {
 751         cdev->private->cdev = cdev;
 752         atomic_set(&cdev->private->onoff, 0);
 753         cdev->dev.parent = &sch->dev;
 754         cdev->dev.release = ccw_device_release;
 755         INIT_WORK(&cdev->private->kick_work, NULL);
 756         cdev->dev.groups = ccwdev_attr_groups;
 757         /* Do first half of device_register. */
 758         device_initialize(&cdev->dev);
 759         if (!get_device(&sch->dev)) {
 760                 if (cdev->dev.release)
 761                         cdev->dev.release(&cdev->dev);
 762                 return -ENODEV;
 763         }
 764         return 0;
 765 }
 766
 767 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 768 {
 769         struct ccw_device *cdev;
 770         int ret;
 771
 772         cdev = io_subchannel_allocate_dev(sch);
 773         if (!IS_ERR(cdev)) {
 774                 ret = io_subchannel_initialize_dev(sch, cdev);
 775                 if (ret) {
 776                         kfree(cdev);
 777                         cdev = ERR_PTR(ret);
 778                 }
 779         }
 780         return cdev;
 781 }
 782
 783 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 784
 785 static void sch_attach_device(struct subchannel *sch,
 786                               struct ccw_device *cdev)
 787 {
 788         css_update_ssd_info(sch);
 789         spin_lock_irq(sch->lock);
 790         sch_set_cdev(sch, cdev);
 791         cdev->private->schid = sch->schid;
 792         cdev->ccwlock = sch->lock;
 793         device_trigger_reprobe(sch);
 794         spin_unlock_irq(sch->lock);
 795 }
 796
 797 static void sch_attach_disconnected_device(struct subchannel *sch,
 798                                            struct ccw_device *cdev)
 799 {
 800         struct subchannel *other_sch;
 801         int ret;
 802
 803         other_sch = to_subchannel(get_device(cdev->dev.parent));
 804         ret = device_move(&cdev->dev, &sch->dev);
 805         if (ret) {
 806                 CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
 807                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 808                               cdev->private->dev_id.devno, ret);
 809                 put_device(&other_sch->dev);
 810                 return;
 811         }
 812         sch_set_cdev(other_sch, NULL);
 813         /* No need to keep a subchannel without ccw device around. */
 814         css_sch_device_unregister(other_sch);
 815         put_device(&other_sch->dev);
 816         sch_attach_device(sch, cdev);
 817 }
 818
 819 static void sch_attach_orphaned_device(struct subchannel *sch,
 820                                        struct ccw_device *cdev)
 821 {
 822         int ret;
 823
 824         /* Try to move the ccw device to its new subchannel. */
 825         ret = device_move(&cdev->dev, &sch->dev);
 826         if (ret) {
 827                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 828                               "failed (ret=%d)!\n",
 829                               cdev->private->dev_id.ssid,
 830                               cdev->private->dev_id.devno, ret);
 831                 return;
 832         }
 833         sch_attach_device(sch, cdev);
 834 }
 835
 836 static void sch_create_and_recog_new_device(struct subchannel *sch)
 837 {
 838         struct ccw_device *cdev;
 839
 840         /* Need to allocate a new ccw device. */
 841         cdev = io_subchannel_create_ccwdev(sch);
 842         if (IS_ERR(cdev)) {
 843                 /* OK, we did everything we could... */
 844                 css_sch_device_unregister(sch);
 845                 return;
 846         }
 847         spin_lock_irq(sch->lock);
 848         sch_set_cdev(sch, cdev);
 849         spin_unlock_irq(sch->lock);
 850         /* Start recognition for the new ccw device. */
 851         if (io_subchannel_recog(cdev, sch)) {
 852                 spin_lock_irq(sch->lock);
 853                 sch_set_cdev(sch, NULL);
 854                 spin_unlock_irq(sch->lock);
 855                 if (cdev->dev.release)
 856                         cdev->dev.release(&cdev->dev);
 857                 css_sch_device_unregister(sch);
 858         }
 859 }
 860
 861
 862 void ccw_device_move_to_orphanage(struct work_struct *work)
 863 {
 864         struct ccw_device_private *priv;
 865         struct ccw_device *cdev;
 866         struct ccw_device *replacing_cdev;
 867         struct subchannel *sch;
 868         int ret;
 869         struct channel_subsystem *css;
 870         struct ccw_dev_id dev_id;
 871
 872         priv = container_of(work, struct ccw_device_private, kick_work);
 873         cdev = priv->cdev;
 874         sch = to_subchannel(cdev->dev.parent);
 875         css = to_css(sch->dev.parent);
 876         dev_id.devno = sch->schib.pmcw.dev;
 877         dev_id.ssid = sch->schid.ssid;
 878
 879         /*
 880          * Move the orphaned ccw device to the orphanage so the replacing
 881          * ccw device can take its place on the subchannel.
 882          */
 883         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 884         if (ret) {
 885                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 886                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 887                               cdev->private->dev_id.devno, ret);
 888                 return;
 889         }
 890         cdev->ccwlock = css->pseudo_subchannel->lock;
 891         /*
 892          * Search for the replacing ccw device
 893          * - among the disconnected devices
 894          * - in the orphanage
 895          */
 896         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 897         if (replacing_cdev) {
 898                 sch_attach_disconnected_device(sch, replacing_cdev);
 899                 return;
 900         }
 901         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 902         if (replacing_cdev) {
 903                 sch_attach_orphaned_device(sch, replacing_cdev);
 904                 return;
 905         }
 906         sch_create_and_recog_new_device(sch);
 907 }
 908
 909 /*
 910  * Register recognized device.
 911  */
 912 static void
 913 io_subchannel_register(struct work_struct *work)
 914 {
 915         struct ccw_device_private *priv;
 916         struct ccw_device *cdev;
 917         struct subchannel *sch;
 918         int ret;
 919         unsigned long flags;
 920
 921         priv = container_of(work, struct ccw_device_private, kick_work);
 922         cdev = priv->cdev;
 923         sch = to_subchannel(cdev->dev.parent);
 924         css_update_ssd_info(sch);
 925         /*
 926          * io_subchannel_register() will also be called after device
 927          * recognition has been done for a boxed device (which will already
 928          * be registered). We need to reprobe since we may now have sense id
 929          * information.
 930          */
 931         if (klist_node_attached(&cdev->dev.knode_parent)) {
 932                 if (!cdev->drv) {
 933                         ret = device_reprobe(&cdev->dev);
 934                         if (ret)
 935                                 /* We can't do much here. */
 936                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 937                                               " %d for 0.%x.%04x\n", ret,
 938                                               cdev->private->dev_id.ssid,
 939                                               cdev->private->dev_id.devno);
 940                 }
 941                 goto out;
 942         }
 943         /*
 944          * Now we know this subchannel will stay, we can throw
 945          * our delayed uevent.
 946          */
 947         sch->dev.uevent_suppress = 0;
 948         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 949         /* make it known to the system */
 950         ret = ccw_device_register(cdev);
 951         if (ret) {
 952                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 953                               cdev->private->dev_id.ssid,
 954                               cdev->private->dev_id.devno, ret);
 955                 put_device(&cdev->dev);
 956                 spin_lock_irqsave(sch->lock, flags);
 957                 sch_set_cdev(sch, NULL);
 958                 spin_unlock_irqrestore(sch->lock, flags);
 959                 kfree (cdev->private);
 960                 kfree (cdev);
 961                 put_device(&sch->dev);
 962                 if (atomic_dec_and_test(&ccw_device_init_count))
 963                         wake_up(&ccw_device_init_wq);
 964                 return;
 965         }
 966         put_device(&cdev->dev);
 967 out:
 968         cdev->private->flags.recog_done = 1;
 969         put_device(&sch->dev);
 970         wake_up(&cdev->private->wait_q);
 971         if (atomic_dec_and_test(&ccw_device_init_count))
 972                 wake_up(&ccw_device_init_wq);
 973 }
 974
 975 static void ccw_device_call_sch_unregister(struct work_struct *work)
 976 {
 977         struct ccw_device_private *priv;
 978         struct ccw_device *cdev;
 979         struct subchannel *sch;
 980
 981         priv = container_of(work, struct ccw_device_private, kick_work);
 982         cdev = priv->cdev;
 983         sch = to_subchannel(cdev->dev.parent);
 984         css_sch_device_unregister(sch);
 985         /* Reset intparm to zeroes. */
 986         sch->schib.pmcw.intparm = 0;
 987         cio_modify(sch);
 988         put_device(&cdev->dev);
 989         put_device(&sch->dev);
 990 }
 991
 992 /*
 993  * subchannel recognition done. Called from the state machine.
 994  */
 995 void
 996 io_subchannel_recog_done(struct ccw_device *cdev)
 997 {
 998         struct subchannel *sch;
 999
1000         if (css_init_done == 0) {
1001                 cdev->private->flags.recog_done = 1;
1002                 return;
1003         }
1004         switch (cdev->private->state) {
1005         case DEV_STATE_NOT_OPER:
1006                 cdev->private->flags.recog_done = 1;
1007                 /* Remove device found not operational. */
1008                 if (!get_device(&cdev->dev))
1009                         break;
1010                 sch = to_subchannel(cdev->dev.parent);
1011                 PREPARE_WORK(&cdev->private->kick_work,
1012                              ccw_device_call_sch_unregister);
1013                 queue_work(slow_path_wq, &cdev->private->kick_work);
1014                 if (atomic_dec_and_test(&ccw_device_init_count))
1015                         wake_up(&ccw_device_init_wq);
1016                 break;
1017         case DEV_STATE_BOXED:
1018                 /* Device did not respond in time. */
1019         case DEV_STATE_OFFLINE:
1020                 /*
1021                  * We can't register the device in interrupt context so
1022                  * we schedule a work item.
1023                  */
1024                 if (!get_device(&cdev->dev))
1025                         break;
1026                 PREPARE_WORK(&cdev->private->kick_work,
1027                              io_subchannel_register);
1028                 queue_work(slow_path_wq, &cdev->private->kick_work);
1029                 break;
1030         }
1031 }
1032
1033 static int
1034 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1035 {
1036         int rc;
1037         struct ccw_device_private *priv;
1038
1039         sch_set_cdev(sch, cdev);
1040         sch->driver = &io_subchannel_driver;
1041         cdev->ccwlock = sch->lock;
1042
1043         /* Init private data. */
1044         priv = cdev->private;
1045         priv->dev_id.devno = sch->schib.pmcw.dev;
1046         priv->dev_id.ssid = sch->schid.ssid;
1047         priv->schid = sch->schid;
1048         priv->state = DEV_STATE_NOT_OPER;
1049         INIT_LIST_HEAD(&priv->cmb_list);
1050         init_waitqueue_head(&priv->wait_q);
1051         init_timer(&priv->timer);
1052
1053         /* Set an initial name for the device. */
1054         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1055                   sch->schid.ssid, sch->schib.pmcw.dev);
1056
1057         /* Increase counter of devices currently in recognition. */
1058         atomic_inc(&ccw_device_init_count);
1059
1060         /* Start async. device sensing. */
1061         spin_lock_irq(sch->lock);
1062         rc = ccw_device_recognition(cdev);
1063         spin_unlock_irq(sch->lock);
1064         if (rc) {
1065                 if (atomic_dec_and_test(&ccw_device_init_count))
1066                         wake_up(&ccw_device_init_wq);
1067         }
1068         return rc;
1069 }
1070
1071 static void ccw_device_move_to_sch(struct work_struct *work)
1072 {
1073         struct ccw_device_private *priv;
1074         int rc;
1075         struct subchannel *sch;
1076         struct ccw_device *cdev;
1077         struct subchannel *former_parent;
1078
1079         priv = container_of(work, struct ccw_device_private, kick_work);
1080         sch = priv->sch;
1081         cdev = priv->cdev;
1082         former_parent = ccw_device_is_orphan(cdev) ?
1083                 NULL : to_subchannel(get_device(cdev->dev.parent));
1084         mutex_lock(&sch->reg_mutex);
1085         /* Try to move the ccw device to its new subchannel. */
1086         rc = device_move(&cdev->dev, &sch->dev);
1087         mutex_unlock(&sch->reg_mutex);
1088         if (rc) {
1089                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
1090                               "0.%x.%04x failed (ret=%d)!\n",
1091                               cdev->private->dev_id.ssid,
1092                               cdev->private->dev_id.devno, sch->schid.ssid,
1093                               sch->schid.sch_no, rc);
1094                 css_sch_device_unregister(sch);
1095                 goto out;
1096         }
1097         if (former_parent) {
1098                 spin_lock_irq(former_parent->lock);
1099                 sch_set_cdev(former_parent, NULL);
1100                 spin_unlock_irq(former_parent->lock);
1101                 css_sch_device_unregister(former_parent);
1102                 /* Reset intparm to zeroes. */
1103                 former_parent->schib.pmcw.intparm = 0;
1104                 cio_modify(former_parent);
1105         }
1106         sch_attach_device(sch, cdev);
1107 out:
1108         if (former_parent)
1109                 put_device(&former_parent->dev);
1110         put_device(&cdev->dev);
1111 }
1112
1113 static void io_subchannel_irq(struct subchannel *sch)
1114 {
1115         struct ccw_device *cdev;
1116
1117         cdev = sch_get_cdev(sch);
1118
1119         CIO_TRACE_EVENT(3, "IRQ");
1120         CIO_TRACE_EVENT(3, sch->dev.bus_id);
1121         if (cdev)
1122                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1123 }
1124
1125 static int
1126 io_subchannel_probe (struct subchannel *sch)
1127 {
1128         struct ccw_device *cdev;
1129         int rc;
1130         unsigned long flags;
1131         struct ccw_dev_id dev_id;
1132
1133         cdev = sch_get_cdev(sch);
1134         if (cdev) {
1135                 /*
1136                  * This subchannel already has an associated ccw_device.
1137                  * Register it and exit. This happens for all early
1138                  * device, e.g. the console.
1139                  */
1140                 cdev->dev.groups = ccwdev_attr_groups;
1141                 device_initialize(&cdev->dev);
1142                 ccw_device_register(cdev);
1143                 /*
1144                  * Check if the device is already online. If it is
1145                  * the reference count needs to be corrected
1146                  * (see ccw_device_online and css_init_done for the
1147                  * ugly details).
1148                  */
1149                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1150                     cdev->private->state != DEV_STATE_OFFLINE &&
1151                     cdev->private->state != DEV_STATE_BOXED)
1152                         get_device(&cdev->dev);
1153                 return 0;
1154         }
1155         /*
1156          * First check if a fitting device may be found amongst the
1157          * disconnected devices or in the orphanage.
1158          */
1159         dev_id.devno = sch->schib.pmcw.dev;
1160         dev_id.ssid = sch->schid.ssid;
1161         /* Allocate I/O subchannel private data. */
1162         sch->private = kzalloc(sizeof(struct io_subchannel_private),
1163                                GFP_KERNEL | GFP_DMA);
1164         if (!sch->private)
1165                 return -ENOMEM;
1166         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1167         if (!cdev)
1168                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1169                                                      &dev_id);
1170         if (cdev) {
1171                 /*
1172                  * Schedule moving the device until when we have a registered
1173                  * subchannel to move to and succeed the probe. We can
1174                  * unregister later again, when the probe is through.
1175                  */
1176                 cdev->private->sch = sch;
1177                 PREPARE_WORK(&cdev->private->kick_work,
1178                              ccw_device_move_to_sch);
1179                 queue_work(slow_path_wq, &cdev->private->kick_work);
1180                 return 0;
1181         }
1182         cdev = io_subchannel_create_ccwdev(sch);
1183         if (IS_ERR(cdev)) {
1184                 kfree(sch->private);
1185                 return PTR_ERR(cdev);
1186         }
1187         rc = io_subchannel_recog(cdev, sch);
1188         if (rc) {
1189                 spin_lock_irqsave(sch->lock, flags);
1190                 sch_set_cdev(sch, NULL);
1191                 spin_unlock_irqrestore(sch->lock, flags);
1192                 if (cdev->dev.release)
1193                         cdev->dev.release(&cdev->dev);
1194                 kfree(sch->private);
1195         }
1196
1197         return rc;
1198 }
1199
1200 static int
1201 io_subchannel_remove (struct subchannel *sch)
1202 {
1203         struct ccw_device *cdev;
1204         unsigned long flags;
1205
1206         cdev = sch_get_cdev(sch);
1207         if (!cdev)
1208                 return 0;
1209         /* Set ccw device to not operational and drop reference. */
1210         spin_lock_irqsave(cdev->ccwlock, flags);
1211         sch_set_cdev(sch, NULL);
1212         cdev->private->state = DEV_STATE_NOT_OPER;
1213         spin_unlock_irqrestore(cdev->ccwlock, flags);
1214         ccw_device_unregister(cdev);
1215         put_device(&cdev->dev);
1216         kfree(sch->private);
1217         return 0;
1218 }
1219
1220 static int io_subchannel_notify(struct subchannel *sch, int event)
1221 {
1222         struct ccw_device *cdev;
1223
1224         cdev = sch_get_cdev(sch);
1225         if (!cdev)
1226                 return 0;
1227         if (!cdev->drv)
1228                 return 0;
1229         if (!cdev->online)
1230                 return 0;
1231         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1232 }
1233
1234 static void io_subchannel_verify(struct subchannel *sch)
1235 {
1236         struct ccw_device *cdev;
1237
1238         cdev = sch_get_cdev(sch);
1239         if (cdev)
1240                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1241 }
1242
1243 static void io_subchannel_ioterm(struct subchannel *sch)
1244 {
1245         struct ccw_device *cdev;
1246
1247         cdev = sch_get_cdev(sch);
1248         if (!cdev)
1249                 return;
1250         /* Internal I/O will be retried by the interrupt handler. */
1251         if (cdev->private->flags.intretry)
1252                 return;
1253         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1254         if (cdev->handler)
1255                 cdev->handler(cdev, cdev->private->intparm,
1256                               ERR_PTR(-EIO));
1257 }
1258
1259 static void
1260 io_subchannel_shutdown(struct subchannel *sch)
1261 {
1262         struct ccw_device *cdev;
1263         int ret;
1264
1265         cdev = sch_get_cdev(sch);
1266
1267         if (cio_is_console(sch->schid))
1268                 return;
1269         if (!sch->schib.pmcw.ena)
1270                 /* Nothing to do. */
1271                 return;
1272         ret = cio_disable_subchannel(sch);
1273         if (ret != -EBUSY)
1274                 /* Subchannel is disabled, we're done. */
1275                 return;
1276         cdev->private->state = DEV_STATE_QUIESCE;
1277         if (cdev->handler)
1278                 cdev->handler(cdev, cdev->private->intparm,
1279                               ERR_PTR(-EIO));
1280         ret = ccw_device_cancel_halt_clear(cdev);
1281         if (ret == -EBUSY) {
1282                 ccw_device_set_timeout(cdev, HZ/10);
1283                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1284         }
1285         cio_disable_subchannel(sch);
1286 }
1287
1288 #ifdef CONFIG_CCW_CONSOLE
1289 static struct ccw_device console_cdev;
1290 static struct ccw_device_private console_private;
1291 static int console_cdev_in_use;
1292
1293 static DEFINE_SPINLOCK(ccw_console_lock);
1294
1295 spinlock_t * cio_get_console_lock(void)
1296 {
1297         return &ccw_console_lock;
1298 }
1299
1300 static int
1301 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1302 {
1303         int rc;
1304
1305         /* Attach subchannel private data. */
1306         sch->private = cio_get_console_priv();
1307         memset(sch->private, 0, sizeof(struct io_subchannel_private));
1308         /* Initialize the ccw_device structure. */
1309         cdev->dev.parent= &sch->dev;
1310         rc = io_subchannel_recog(cdev, sch);
1311         if (rc)
1312                 return rc;
1313
1314         /* Now wait for the async. recognition to come to an end. */
1315         spin_lock_irq(cdev->ccwlock);
1316         while (!dev_fsm_final_state(cdev))
1317                 wait_cons_dev();
1318         rc = -EIO;
1319         if (cdev->private->state != DEV_STATE_OFFLINE)
1320                 goto out_unlock;
1321         ccw_device_online(cdev);
1322         while (!dev_fsm_final_state(cdev))
1323                 wait_cons_dev();
1324         if (cdev->private->state != DEV_STATE_ONLINE)
1325                 goto out_unlock;
1326         rc = 0;
1327 out_unlock:
1328         spin_unlock_irq(cdev->ccwlock);
1329         return 0;
1330 }
1331
1332 struct ccw_device *
1333 ccw_device_probe_console(void)
1334 {
1335         struct subchannel *sch;
1336         int ret;
1337
1338         if (xchg(&console_cdev_in_use, 1) != 0)
1339                 return ERR_PTR(-EBUSY);
1340         sch = cio_probe_console();
1341         if (IS_ERR(sch)) {
1342                 console_cdev_in_use = 0;
1343                 return (void *) sch;
1344         }
1345         memset(&console_cdev, 0, sizeof(struct ccw_device));
1346         memset(&console_private, 0, sizeof(struct ccw_device_private));
1347         console_cdev.private = &console_private;
1348         console_private.cdev = &console_cdev;
1349         ret = ccw_device_console_enable(&console_cdev, sch);
1350         if (ret) {
1351                 cio_release_console();
1352                 console_cdev_in_use = 0;
1353                 return ERR_PTR(ret);
1354         }
1355         console_cdev.online = 1;
1356         return &console_cdev;
1357 }
1358 #endif
1359
1360 /*
1361  * get ccw_device matching the busid, but only if owned by cdrv
1362  */
1363 static int
1364 __ccwdev_check_busid(struct device *dev, void *id)
1365 {
1366         char *bus_id;
1367
1368         bus_id = id;
1369
1370         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1371 }
1372
1373
1374 /**
1375  * get_ccwdev_by_busid() - obtain device from a bus id
1376  * @cdrv: driver the device is owned by
1377  * @bus_id: bus id of the device to be searched
1378  *
1379  * This function searches all devices owned by @cdrv for a device with a bus
1380  * id matching @bus_id.
1381  * Returns:
1382  *  If a match is found, its reference count of the found device is increased
1383  *  and it is returned; else %NULL is returned.
1384  */
1385 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1386                                        const char *bus_id)
1387 {
1388         struct device *dev;
1389         struct device_driver *drv;
1390
1391         drv = get_driver(&cdrv->driver);
1392         if (!drv)
1393                 return NULL;
1394
1395         dev = driver_find_device(drv, NULL, (void *)bus_id,
1396                                  __ccwdev_check_busid);
1397         put_driver(drv);
1398
1399         return dev ? to_ccwdev(dev) : NULL;
1400 }
1401
1402 /************************** device driver handling ************************/
1403
1404 /* This is the implementation of the ccw_driver class. The probe, remove
1405  * and release methods are initially very similar to the device_driver
1406  * implementations, with the difference that they have ccw_device
1407  * arguments.
1408  *
1409  * A ccw driver also contains the information that is needed for
1410  * device matching.
1411  */
1412 static int
1413 ccw_device_probe (struct device *dev)
1414 {
1415         struct ccw_device *cdev = to_ccwdev(dev);
1416         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1417         int ret;
1418
1419         cdev->drv = cdrv; /* to let the driver call _set_online */
1420
1421         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1422
1423         if (ret) {
1424                 cdev->drv = NULL;
1425                 return ret;
1426         }
1427
1428         return 0;
1429 }
1430
1431 static int
1432 ccw_device_remove (struct device *dev)
1433 {
1434         struct ccw_device *cdev = to_ccwdev(dev);
1435         struct ccw_driver *cdrv = cdev->drv;
1436         int ret;
1437
1438         if (cdrv->remove)
1439                 cdrv->remove(cdev);
1440         if (cdev->online) {
1441                 cdev->online = 0;
1442                 spin_lock_irq(cdev->ccwlock);
1443                 ret = ccw_device_offline(cdev);
1444                 spin_unlock_irq(cdev->ccwlock);
1445                 if (ret == 0)
1446                         wait_event(cdev->private->wait_q,
1447                                    dev_fsm_final_state(cdev));
1448                 else
1449                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1450                                       "device 0.%x.%04x\n",
1451                                       ret, cdev->private->dev_id.ssid,
1452                                       cdev->private->dev_id.devno);
1453         }
1454         ccw_device_set_timeout(cdev, 0);
1455         cdev->drv = NULL;
1456         return 0;
1457 }
1458
1459 static void ccw_device_shutdown(struct device *dev)
1460 {
1461         struct ccw_device *cdev;
1462
1463         cdev = to_ccwdev(dev);
1464         if (cdev->drv && cdev->drv->shutdown)
1465                 cdev->drv->shutdown(cdev);
1466         disable_cmf(cdev);
1467 }
1468
1469 struct bus_type ccw_bus_type = {
1470         .name   = "ccw",
1471         .match  = ccw_bus_match,
1472         .uevent = ccw_uevent,
1473         .probe  = ccw_device_probe,
1474         .remove = ccw_device_remove,
1475         .shutdown = ccw_device_shutdown,
1476 };
1477
1478 /**
1479  * ccw_driver_register() - register a ccw driver
1480  * @cdriver: driver to be registered
1481  *
1482  * This function is mainly a wrapper around driver_register().
1483  * Returns:
1484  *   %0 on success and a negative error value on failure.
1485  */
1486 int ccw_driver_register(struct ccw_driver *cdriver)
1487 {
1488         struct device_driver *drv = &cdriver->driver;
1489
1490         drv->bus = &ccw_bus_type;
1491         drv->name = cdriver->name;
1492         drv->owner = cdriver->owner;
1493
1494         return driver_register(drv);
1495 }
1496
1497 /**
1498  * ccw_driver_unregister() - deregister a ccw driver
1499  * @cdriver: driver to be deregistered
1500  *
1501  * This function is mainly a wrapper around driver_unregister().
1502  */
1503 void ccw_driver_unregister(struct ccw_driver *cdriver)
1504 {
1505         driver_unregister(&cdriver->driver);
1506 }
1507
1508 /* Helper func for qdio. */
1509 struct subchannel_id
1510 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1511 {
1512         struct subchannel *sch;
1513
1514         sch = to_subchannel(cdev->dev.parent);
1515         return sch->schid;
1516 }
1517
1518 static int recovery_check(struct device *dev, void *data)
1519 {
1520         struct ccw_device *cdev = to_ccwdev(dev);
1521         int *redo = data;
1522
1523         spin_lock_irq(cdev->ccwlock);
1524         switch (cdev->private->state) {
1525         case DEV_STATE_DISCONNECTED:
1526                 CIO_MSG_EVENT(4, "recovery: trigger 0.%x.%04x\n",
1527                               cdev->private->dev_id.ssid,
1528                               cdev->private->dev_id.devno);
1529                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1530                 *redo = 1;
1531                 break;
1532         case DEV_STATE_DISCONNECTED_SENSE_ID:
1533                 *redo = 1;
1534                 break;
1535         }
1536         spin_unlock_irq(cdev->ccwlock);
1537
1538         return 0;
1539 }
1540
1541 static void recovery_work_func(struct work_struct *unused)
1542 {
1543         int redo = 0;
1544
1545         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1546         if (redo) {
1547                 spin_lock_irq(&recovery_lock);
1548                 if (!timer_pending(&recovery_timer)) {
1549                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1550                                 recovery_phase++;
1551                         mod_timer(&recovery_timer, jiffies +
1552                                   recovery_delay[recovery_phase] * HZ);
1553                 }
1554                 spin_unlock_irq(&recovery_lock);
1555         } else
1556                 CIO_MSG_EVENT(4, "recovery: end\n");
1557 }
1558
1559 static DECLARE_WORK(recovery_work, recovery_work_func);
1560
1561 static void recovery_func(unsigned long data)
1562 {
1563         /*
1564          * We can't do our recovery in softirq context and it's not
1565          * performance critical, so we schedule it.
1566          */
1567         schedule_work(&recovery_work);
1568 }
1569
1570 void ccw_device_schedule_recovery(void)
1571 {
1572         unsigned long flags;
1573
1574         CIO_MSG_EVENT(4, "recovery: schedule\n");
1575         spin_lock_irqsave(&recovery_lock, flags);
1576         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1577                 recovery_phase = 0;
1578                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1579         }
1580         spin_unlock_irqrestore(&recovery_lock, flags);
1581 }
1582
1583 MODULE_LICENSE("GPL");
1584 EXPORT_SYMBOL(ccw_device_set_online);
1585 EXPORT_SYMBOL(ccw_device_set_offline);
1586 EXPORT_SYMBOL(ccw_driver_register);
1587 EXPORT_SYMBOL(ccw_driver_unregister);
1588 EXPORT_SYMBOL(get_ccwdev_by_busid);
1589 EXPORT_SYMBOL(ccw_bus_type);
1590 EXPORT_SYMBOL(ccw_device_work);
1591 EXPORT_SYMBOL(ccw_device_notify_work);
1592 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);