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, char **envp, int num_envp,
  82                       char *buffer, int buffer_size)
  83 {
  84         struct ccw_device *cdev = to_ccwdev(dev);
  85         struct ccw_device_id *id = &(cdev->id);
  86         int i = 0;
  87         int len = 0;
  88         int ret;
  89         char modalias_buf[30];
  90
  91         /* CU_TYPE= */
  92         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
  93                              "CU_TYPE=%04X", id->cu_type);
  94         if (ret)
  95                 return ret;
  96
  97         /* CU_MODEL= */
  98         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
  99                              "CU_MODEL=%02X", id->cu_model);
 100         if (ret)
 101                 return ret;
 102
 103         /* The next two can be zero, that's ok for us */
 104         /* DEV_TYPE= */
 105         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
 106                              "DEV_TYPE=%04X", id->dev_type);
 107         if (ret)
 108                 return ret;
 109
 110         /* DEV_MODEL= */
 111         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
 112                              "DEV_MODEL=%02X", id->dev_model);
 113         if (ret)
 114                 return ret;
 115
 116         /* MODALIAS=  */
 117         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 118         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
 119                              "MODALIAS=%s", modalias_buf);
 120         if (ret)
 121                 return ret;
 122         envp[i] = NULL;
 123         return 0;
 124 }
 125
 126 struct bus_type ccw_bus_type;
 127
 128 static int io_subchannel_probe (struct subchannel *);
 129 static int io_subchannel_remove (struct subchannel *);
 130 static int io_subchannel_notify(struct device *, int);
 131 static void io_subchannel_verify(struct device *);
 132 static void io_subchannel_ioterm(struct device *);
 133 static void io_subchannel_shutdown(struct subchannel *);
 134
 135 static struct css_driver io_subchannel_driver = {
 136         .subchannel_type = SUBCHANNEL_TYPE_IO,
 137         .drv = {
 138                 .name = "io_subchannel",
 139                 .bus  = &css_bus_type,
 140         },
 141         .irq = io_subchannel_irq,
 142         .notify = io_subchannel_notify,
 143         .verify = io_subchannel_verify,
 144         .termination = io_subchannel_ioterm,
 145         .probe = io_subchannel_probe,
 146         .remove = io_subchannel_remove,
 147         .shutdown = io_subchannel_shutdown,
 148 };
 149
 150 struct workqueue_struct *ccw_device_work;
 151 struct workqueue_struct *ccw_device_notify_work;
 152 wait_queue_head_t ccw_device_init_wq;
 153 atomic_t ccw_device_init_count;
 154
 155 static int __init
 156 init_ccw_bus_type (void)
 157 {
 158         int ret;
 159
 160         init_waitqueue_head(&ccw_device_init_wq);
 161         atomic_set(&ccw_device_init_count, 0);
 162
 163         ccw_device_work = create_singlethread_workqueue("cio");
 164         if (!ccw_device_work)
 165                 return -ENOMEM; /* FIXME: better errno ? */
 166         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 167         if (!ccw_device_notify_work) {
 168                 ret = -ENOMEM; /* FIXME: better errno ? */
 169                 goto out_err;
 170         }
 171         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 172         if (!slow_path_wq) {
 173                 ret = -ENOMEM; /* FIXME: better errno ? */
 174                 goto out_err;
 175         }
 176         if ((ret = bus_register (&ccw_bus_type)))
 177                 goto out_err;
 178
 179         if ((ret = driver_register(&io_subchannel_driver.drv)))
 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         driver_unregister(&io_subchannel_driver.drv);
 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(2, "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(2, "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(2, "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(2, "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(2, "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 i, force;
 516         char *tmp;
 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         } else {
 529                 force = 0;
 530                 i = simple_strtoul(buf, &tmp, 16);
 531         }
 532
 533         switch (i) {
 534         case 0:
 535                 online_store_handle_offline(cdev);
 536                 break;
 537         case 1:
 538                 online_store_handle_online(cdev, force);
 539                 break;
 540         default:
 541                 count = -EINVAL;
 542         }
 543         if (cdev->drv)
 544                 module_put(cdev->drv->owner);
 545         atomic_set(&cdev->private->onoff, 0);
 546         return count;
 547 }
 548
 549 static ssize_t
 550 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 551 {
 552         struct ccw_device *cdev = to_ccwdev(dev);
 553         struct subchannel *sch;
 554
 555         if (ccw_device_is_orphan(cdev))
 556                 return sprintf(buf, "no device\n");
 557         switch (cdev->private->state) {
 558         case DEV_STATE_BOXED:
 559                 return sprintf(buf, "boxed\n");
 560         case DEV_STATE_DISCONNECTED:
 561         case DEV_STATE_DISCONNECTED_SENSE_ID:
 562         case DEV_STATE_NOT_OPER:
 563                 sch = to_subchannel(dev->parent);
 564                 if (!sch->lpm)
 565                         return sprintf(buf, "no path\n");
 566                 else
 567                         return sprintf(buf, "no device\n");
 568         default:
 569                 /* All other states considered fine. */
 570                 return sprintf(buf, "good\n");
 571         }
 572 }
 573
 574 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 575 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 576 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 577 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 578 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 579 static DEVICE_ATTR(online, 0644, online_show, online_store);
 580 extern struct device_attribute dev_attr_cmb_enable;
 581 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 582
 583 static struct attribute * subch_attrs[] = {
 584         &dev_attr_chpids.attr,
 585         &dev_attr_pimpampom.attr,
 586         NULL,
 587 };
 588
 589 static struct attribute_group subch_attr_group = {
 590         .attrs = subch_attrs,
 591 };
 592
 593 struct attribute_group *subch_attr_groups[] = {
 594         &subch_attr_group,
 595         NULL,
 596 };
 597
 598 static struct attribute * ccwdev_attrs[] = {
 599         &dev_attr_devtype.attr,
 600         &dev_attr_cutype.attr,
 601         &dev_attr_modalias.attr,
 602         &dev_attr_online.attr,
 603         &dev_attr_cmb_enable.attr,
 604         &dev_attr_availability.attr,
 605         NULL,
 606 };
 607
 608 static struct attribute_group ccwdev_attr_group = {
 609         .attrs = ccwdev_attrs,
 610 };
 611
 612 static struct attribute_group *ccwdev_attr_groups[] = {
 613         &ccwdev_attr_group,
 614         NULL,
 615 };
 616
 617 /* this is a simple abstraction for device_register that sets the
 618  * correct bus type and adds the bus specific files */
 619 static int ccw_device_register(struct ccw_device *cdev)
 620 {
 621         struct device *dev = &cdev->dev;
 622         int ret;
 623
 624         dev->bus = &ccw_bus_type;
 625
 626         if ((ret = device_add(dev)))
 627                 return ret;
 628
 629         set_bit(1, &cdev->private->registered);
 630         return ret;
 631 }
 632
 633 struct match_data {
 634         struct ccw_dev_id dev_id;
 635         struct ccw_device * sibling;
 636 };
 637
 638 static int
 639 match_devno(struct device * dev, void * data)
 640 {
 641         struct match_data * d = data;
 642         struct ccw_device * cdev;
 643
 644         cdev = to_ccwdev(dev);
 645         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 646             !ccw_device_is_orphan(cdev) &&
 647             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 648             (cdev != d->sibling))
 649                 return 1;
 650         return 0;
 651 }
 652
 653 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 654                                                      struct ccw_device *sibling)
 655 {
 656         struct device *dev;
 657         struct match_data data;
 658
 659         data.dev_id = *dev_id;
 660         data.sibling = sibling;
 661         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 662
 663         return dev ? to_ccwdev(dev) : NULL;
 664 }
 665
 666 static int match_orphan(struct device *dev, void *data)
 667 {
 668         struct ccw_dev_id *dev_id;
 669         struct ccw_device *cdev;
 670
 671         dev_id = data;
 672         cdev = to_ccwdev(dev);
 673         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 674 }
 675
 676 static struct ccw_device *
 677 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 678                               struct ccw_dev_id *dev_id)
 679 {
 680         struct device *dev;
 681
 682         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 683                                 match_orphan);
 684
 685         return dev ? to_ccwdev(dev) : NULL;
 686 }
 687
 688 static void
 689 ccw_device_add_changed(struct work_struct *work)
 690 {
 691         struct ccw_device_private *priv;
 692         struct ccw_device *cdev;
 693
 694         priv = container_of(work, struct ccw_device_private, kick_work);
 695         cdev = priv->cdev;
 696         if (device_add(&cdev->dev)) {
 697                 put_device(&cdev->dev);
 698                 return;
 699         }
 700         set_bit(1, &cdev->private->registered);
 701 }
 702
 703 void ccw_device_do_unreg_rereg(struct work_struct *work)
 704 {
 705         struct ccw_device_private *priv;
 706         struct ccw_device *cdev;
 707         struct subchannel *sch;
 708
 709         priv = container_of(work, struct ccw_device_private, kick_work);
 710         cdev = priv->cdev;
 711         sch = to_subchannel(cdev->dev.parent);
 712
 713         ccw_device_unregister(cdev);
 714         PREPARE_WORK(&cdev->private->kick_work,
 715                      ccw_device_add_changed);
 716         queue_work(ccw_device_work, &cdev->private->kick_work);
 717 }
 718
 719 static void
 720 ccw_device_release(struct device *dev)
 721 {
 722         struct ccw_device *cdev;
 723
 724         cdev = to_ccwdev(dev);
 725         kfree(cdev->private);
 726         kfree(cdev);
 727 }
 728
 729 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 730 {
 731         struct ccw_device *cdev;
 732
 733         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 734         if (cdev) {
 735                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 736                                         GFP_KERNEL | GFP_DMA);
 737                 if (cdev->private)
 738                         return cdev;
 739         }
 740         kfree(cdev);
 741         return ERR_PTR(-ENOMEM);
 742 }
 743
 744 static int io_subchannel_initialize_dev(struct subchannel *sch,
 745                                         struct ccw_device *cdev)
 746 {
 747         cdev->private->cdev = cdev;
 748         atomic_set(&cdev->private->onoff, 0);
 749         cdev->dev.parent = &sch->dev;
 750         cdev->dev.release = ccw_device_release;
 751         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
 752         cdev->dev.groups = ccwdev_attr_groups;
 753         /* Do first half of device_register. */
 754         device_initialize(&cdev->dev);
 755         if (!get_device(&sch->dev)) {
 756                 if (cdev->dev.release)
 757                         cdev->dev.release(&cdev->dev);
 758                 return -ENODEV;
 759         }
 760         return 0;
 761 }
 762
 763 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 764 {
 765         struct ccw_device *cdev;
 766         int ret;
 767
 768         cdev = io_subchannel_allocate_dev(sch);
 769         if (!IS_ERR(cdev)) {
 770                 ret = io_subchannel_initialize_dev(sch, cdev);
 771                 if (ret) {
 772                         kfree(cdev);
 773                         cdev = ERR_PTR(ret);
 774                 }
 775         }
 776         return cdev;
 777 }
 778
 779 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 780
 781 static void sch_attach_device(struct subchannel *sch,
 782                               struct ccw_device *cdev)
 783 {
 784         css_update_ssd_info(sch);
 785         spin_lock_irq(sch->lock);
 786         sch->dev.driver_data = cdev;
 787         cdev->private->schid = sch->schid;
 788         cdev->ccwlock = sch->lock;
 789         device_trigger_reprobe(sch);
 790         spin_unlock_irq(sch->lock);
 791 }
 792
 793 static void sch_attach_disconnected_device(struct subchannel *sch,
 794                                            struct ccw_device *cdev)
 795 {
 796         struct subchannel *other_sch;
 797         int ret;
 798
 799         other_sch = to_subchannel(get_device(cdev->dev.parent));
 800         ret = device_move(&cdev->dev, &sch->dev);
 801         if (ret) {
 802                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
 803                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 804                               cdev->private->dev_id.devno, ret);
 805                 put_device(&other_sch->dev);
 806                 return;
 807         }
 808         other_sch->dev.driver_data = NULL;
 809         /* No need to keep a subchannel without ccw device around. */
 810         css_sch_device_unregister(other_sch);
 811         put_device(&other_sch->dev);
 812         sch_attach_device(sch, cdev);
 813 }
 814
 815 static void sch_attach_orphaned_device(struct subchannel *sch,
 816                                        struct ccw_device *cdev)
 817 {
 818         int ret;
 819
 820         /* Try to move the ccw device to its new subchannel. */
 821         ret = device_move(&cdev->dev, &sch->dev);
 822         if (ret) {
 823                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 824                               "failed (ret=%d)!\n",
 825                               cdev->private->dev_id.ssid,
 826                               cdev->private->dev_id.devno, ret);
 827                 return;
 828         }
 829         sch_attach_device(sch, cdev);
 830 }
 831
 832 static void sch_create_and_recog_new_device(struct subchannel *sch)
 833 {
 834         struct ccw_device *cdev;
 835
 836         /* Need to allocate a new ccw device. */
 837         cdev = io_subchannel_create_ccwdev(sch);
 838         if (IS_ERR(cdev)) {
 839                 /* OK, we did everything we could... */
 840                 css_sch_device_unregister(sch);
 841                 return;
 842         }
 843         spin_lock_irq(sch->lock);
 844         sch->dev.driver_data = cdev;
 845         spin_unlock_irq(sch->lock);
 846         /* Start recognition for the new ccw device. */
 847         if (io_subchannel_recog(cdev, sch)) {
 848                 spin_lock_irq(sch->lock);
 849                 sch->dev.driver_data = NULL;
 850                 spin_unlock_irq(sch->lock);
 851                 if (cdev->dev.release)
 852                         cdev->dev.release(&cdev->dev);
 853                 css_sch_device_unregister(sch);
 854         }
 855 }
 856
 857
 858 void ccw_device_move_to_orphanage(struct work_struct *work)
 859 {
 860         struct ccw_device_private *priv;
 861         struct ccw_device *cdev;
 862         struct ccw_device *replacing_cdev;
 863         struct subchannel *sch;
 864         int ret;
 865         struct channel_subsystem *css;
 866         struct ccw_dev_id dev_id;
 867
 868         priv = container_of(work, struct ccw_device_private, kick_work);
 869         cdev = priv->cdev;
 870         sch = to_subchannel(cdev->dev.parent);
 871         css = to_css(sch->dev.parent);
 872         dev_id.devno = sch->schib.pmcw.dev;
 873         dev_id.ssid = sch->schid.ssid;
 874
 875         /*
 876          * Move the orphaned ccw device to the orphanage so the replacing
 877          * ccw device can take its place on the subchannel.
 878          */
 879         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 880         if (ret) {
 881                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 882                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 883                               cdev->private->dev_id.devno, ret);
 884                 return;
 885         }
 886         cdev->ccwlock = css->pseudo_subchannel->lock;
 887         /*
 888          * Search for the replacing ccw device
 889          * - among the disconnected devices
 890          * - in the orphanage
 891          */
 892         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 893         if (replacing_cdev) {
 894                 sch_attach_disconnected_device(sch, replacing_cdev);
 895                 return;
 896         }
 897         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 898         if (replacing_cdev) {
 899                 sch_attach_orphaned_device(sch, replacing_cdev);
 900                 return;
 901         }
 902         sch_create_and_recog_new_device(sch);
 903 }
 904
 905 /*
 906  * Register recognized device.
 907  */
 908 static void
 909 io_subchannel_register(struct work_struct *work)
 910 {
 911         struct ccw_device_private *priv;
 912         struct ccw_device *cdev;
 913         struct subchannel *sch;
 914         int ret;
 915         unsigned long flags;
 916
 917         priv = container_of(work, struct ccw_device_private, kick_work);
 918         cdev = priv->cdev;
 919         sch = to_subchannel(cdev->dev.parent);
 920         css_update_ssd_info(sch);
 921         /*
 922          * io_subchannel_register() will also be called after device
 923          * recognition has been done for a boxed device (which will already
 924          * be registered). We need to reprobe since we may now have sense id
 925          * information.
 926          */
 927         if (klist_node_attached(&cdev->dev.knode_parent)) {
 928                 if (!cdev->drv) {
 929                         ret = device_reprobe(&cdev->dev);
 930                         if (ret)
 931                                 /* We can't do much here. */
 932                                 CIO_MSG_EVENT(2, "device_reprobe() returned"
 933                                               " %d for 0.%x.%04x\n", ret,
 934                                               cdev->private->dev_id.ssid,
 935                                               cdev->private->dev_id.devno);
 936                 }
 937                 goto out;
 938         }
 939         /*
 940          * Now we know this subchannel will stay, we can throw
 941          * our delayed uevent.
 942          */
 943         sch->dev.uevent_suppress = 0;
 944         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 945         /* make it known to the system */
 946         ret = ccw_device_register(cdev);
 947         if (ret) {
 948                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 949                               cdev->private->dev_id.ssid,
 950                               cdev->private->dev_id.devno, ret);
 951                 put_device(&cdev->dev);
 952                 spin_lock_irqsave(sch->lock, flags);
 953                 sch->dev.driver_data = NULL;
 954                 spin_unlock_irqrestore(sch->lock, flags);
 955                 kfree (cdev->private);
 956                 kfree (cdev);
 957                 put_device(&sch->dev);
 958                 if (atomic_dec_and_test(&ccw_device_init_count))
 959                         wake_up(&ccw_device_init_wq);
 960                 return;
 961         }
 962         put_device(&cdev->dev);
 963 out:
 964         cdev->private->flags.recog_done = 1;
 965         put_device(&sch->dev);
 966         wake_up(&cdev->private->wait_q);
 967         if (atomic_dec_and_test(&ccw_device_init_count))
 968                 wake_up(&ccw_device_init_wq);
 969 }
 970
 971 void
 972 ccw_device_call_sch_unregister(struct work_struct *work)
 973 {
 974         struct ccw_device_private *priv;
 975         struct ccw_device *cdev;
 976         struct subchannel *sch;
 977
 978         priv = container_of(work, struct ccw_device_private, kick_work);
 979         cdev = priv->cdev;
 980         sch = to_subchannel(cdev->dev.parent);
 981         css_sch_device_unregister(sch);
 982         /* Reset intparm to zeroes. */
 983         sch->schib.pmcw.intparm = 0;
 984         cio_modify(sch);
 985         put_device(&cdev->dev);
 986         put_device(&sch->dev);
 987 }
 988
 989 /*
 990  * subchannel recognition done. Called from the state machine.
 991  */
 992 void
 993 io_subchannel_recog_done(struct ccw_device *cdev)
 994 {
 995         struct subchannel *sch;
 996
 997         if (css_init_done == 0) {
 998                 cdev->private->flags.recog_done = 1;
 999                 return;
1000         }
1001         switch (cdev->private->state) {
1002         case DEV_STATE_NOT_OPER:
1003                 cdev->private->flags.recog_done = 1;
1004                 /* Remove device found not operational. */
1005                 if (!get_device(&cdev->dev))
1006                         break;
1007                 sch = to_subchannel(cdev->dev.parent);
1008                 PREPARE_WORK(&cdev->private->kick_work,
1009                              ccw_device_call_sch_unregister);
1010                 queue_work(slow_path_wq, &cdev->private->kick_work);
1011                 if (atomic_dec_and_test(&ccw_device_init_count))
1012                         wake_up(&ccw_device_init_wq);
1013                 break;
1014         case DEV_STATE_BOXED:
1015                 /* Device did not respond in time. */
1016         case DEV_STATE_OFFLINE:
1017                 /*
1018                  * We can't register the device in interrupt context so
1019                  * we schedule a work item.
1020                  */
1021                 if (!get_device(&cdev->dev))
1022                         break;
1023                 PREPARE_WORK(&cdev->private->kick_work,
1024                              io_subchannel_register);
1025                 queue_work(slow_path_wq, &cdev->private->kick_work);
1026                 break;
1027         }
1028 }
1029
1030 static int
1031 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1032 {
1033         int rc;
1034         struct ccw_device_private *priv;
1035
1036         sch->dev.driver_data = cdev;
1037         sch->driver = &io_subchannel_driver;
1038         cdev->ccwlock = sch->lock;
1039
1040         /* Init private data. */
1041         priv = cdev->private;
1042         priv->dev_id.devno = sch->schib.pmcw.dev;
1043         priv->dev_id.ssid = sch->schid.ssid;
1044         priv->schid = sch->schid;
1045         priv->state = DEV_STATE_NOT_OPER;
1046         INIT_LIST_HEAD(&priv->cmb_list);
1047         init_waitqueue_head(&priv->wait_q);
1048         init_timer(&priv->timer);
1049
1050         /* Set an initial name for the device. */
1051         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1052                   sch->schid.ssid, sch->schib.pmcw.dev);
1053
1054         /* Increase counter of devices currently in recognition. */
1055         atomic_inc(&ccw_device_init_count);
1056
1057         /* Start async. device sensing. */
1058         spin_lock_irq(sch->lock);
1059         rc = ccw_device_recognition(cdev);
1060         spin_unlock_irq(sch->lock);
1061         if (rc) {
1062                 if (atomic_dec_and_test(&ccw_device_init_count))
1063                         wake_up(&ccw_device_init_wq);
1064         }
1065         return rc;
1066 }
1067
1068 static void ccw_device_move_to_sch(struct work_struct *work)
1069 {
1070         struct ccw_device_private *priv;
1071         int rc;
1072         struct subchannel *sch;
1073         struct ccw_device *cdev;
1074         struct subchannel *former_parent;
1075
1076         priv = container_of(work, struct ccw_device_private, kick_work);
1077         sch = priv->sch;
1078         cdev = priv->cdev;
1079         former_parent = ccw_device_is_orphan(cdev) ?
1080                 NULL : to_subchannel(get_device(cdev->dev.parent));
1081         mutex_lock(&sch->reg_mutex);
1082         /* Try to move the ccw device to its new subchannel. */
1083         rc = device_move(&cdev->dev, &sch->dev);
1084         mutex_unlock(&sch->reg_mutex);
1085         if (rc) {
1086                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1087                               "0.%x.%04x failed (ret=%d)!\n",
1088                               cdev->private->dev_id.ssid,
1089                               cdev->private->dev_id.devno, sch->schid.ssid,
1090                               sch->schid.sch_no, rc);
1091                 css_sch_device_unregister(sch);
1092                 goto out;
1093         }
1094         if (former_parent) {
1095                 spin_lock_irq(former_parent->lock);
1096                 former_parent->dev.driver_data = NULL;
1097                 spin_unlock_irq(former_parent->lock);
1098                 css_sch_device_unregister(former_parent);
1099                 /* Reset intparm to zeroes. */
1100                 former_parent->schib.pmcw.intparm = 0;
1101                 cio_modify(former_parent);
1102         }
1103         sch_attach_device(sch, cdev);
1104 out:
1105         if (former_parent)
1106                 put_device(&former_parent->dev);
1107         put_device(&cdev->dev);
1108 }
1109
1110 static int
1111 io_subchannel_probe (struct subchannel *sch)
1112 {
1113         struct ccw_device *cdev;
1114         int rc;
1115         unsigned long flags;
1116         struct ccw_dev_id dev_id;
1117
1118         if (sch->dev.driver_data) {
1119                 /*
1120                  * This subchannel already has an associated ccw_device.
1121                  * Register it and exit. This happens for all early
1122                  * device, e.g. the console.
1123                  */
1124                 cdev = sch->dev.driver_data;
1125                 device_initialize(&cdev->dev);
1126                 ccw_device_register(cdev);
1127                 /*
1128                  * Check if the device is already online. If it is
1129                  * the reference count needs to be corrected
1130                  * (see ccw_device_online and css_init_done for the
1131                  * ugly details).
1132                  */
1133                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1134                     cdev->private->state != DEV_STATE_OFFLINE &&
1135                     cdev->private->state != DEV_STATE_BOXED)
1136                         get_device(&cdev->dev);
1137                 return 0;
1138         }
1139         /*
1140          * First check if a fitting device may be found amongst the
1141          * disconnected devices or in the orphanage.
1142          */
1143         dev_id.devno = sch->schib.pmcw.dev;
1144         dev_id.ssid = sch->schid.ssid;
1145         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1146         if (!cdev)
1147                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1148                                                      &dev_id);
1149         if (cdev) {
1150                 /*
1151                  * Schedule moving the device until when we have a registered
1152                  * subchannel to move to and succeed the probe. We can
1153                  * unregister later again, when the probe is through.
1154                  */
1155                 cdev->private->sch = sch;
1156                 PREPARE_WORK(&cdev->private->kick_work,
1157                              ccw_device_move_to_sch);
1158                 queue_work(slow_path_wq, &cdev->private->kick_work);
1159                 return 0;
1160         }
1161         cdev = io_subchannel_create_ccwdev(sch);
1162         if (IS_ERR(cdev))
1163                 return PTR_ERR(cdev);
1164
1165         rc = io_subchannel_recog(cdev, sch);
1166         if (rc) {
1167                 spin_lock_irqsave(sch->lock, flags);
1168                 sch->dev.driver_data = NULL;
1169                 spin_unlock_irqrestore(sch->lock, flags);
1170                 if (cdev->dev.release)
1171                         cdev->dev.release(&cdev->dev);
1172         }
1173
1174         return rc;
1175 }
1176
1177 static int
1178 io_subchannel_remove (struct subchannel *sch)
1179 {
1180         struct ccw_device *cdev;
1181         unsigned long flags;
1182
1183         if (!sch->dev.driver_data)
1184                 return 0;
1185         cdev = sch->dev.driver_data;
1186         /* Set ccw device to not operational and drop reference. */
1187         spin_lock_irqsave(cdev->ccwlock, flags);
1188         sch->dev.driver_data = NULL;
1189         cdev->private->state = DEV_STATE_NOT_OPER;
1190         spin_unlock_irqrestore(cdev->ccwlock, flags);
1191         ccw_device_unregister(cdev);
1192         put_device(&cdev->dev);
1193         return 0;
1194 }
1195
1196 static int
1197 io_subchannel_notify(struct device *dev, int event)
1198 {
1199         struct ccw_device *cdev;
1200
1201         cdev = dev->driver_data;
1202         if (!cdev)
1203                 return 0;
1204         if (!cdev->drv)
1205                 return 0;
1206         if (!cdev->online)
1207                 return 0;
1208         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1209 }
1210
1211 static void
1212 io_subchannel_verify(struct device *dev)
1213 {
1214         struct ccw_device *cdev;
1215
1216         cdev = dev->driver_data;
1217         if (cdev)
1218                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1219 }
1220
1221 static void
1222 io_subchannel_ioterm(struct device *dev)
1223 {
1224         struct ccw_device *cdev;
1225
1226         cdev = dev->driver_data;
1227         if (!cdev)
1228                 return;
1229         /* Internal I/O will be retried by the interrupt handler. */
1230         if (cdev->private->flags.intretry)
1231                 return;
1232         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1233         if (cdev->handler)
1234                 cdev->handler(cdev, cdev->private->intparm,
1235                               ERR_PTR(-EIO));
1236 }
1237
1238 static void
1239 io_subchannel_shutdown(struct subchannel *sch)
1240 {
1241         struct ccw_device *cdev;
1242         int ret;
1243
1244         cdev = sch->dev.driver_data;
1245
1246         if (cio_is_console(sch->schid))
1247                 return;
1248         if (!sch->schib.pmcw.ena)
1249                 /* Nothing to do. */
1250                 return;
1251         ret = cio_disable_subchannel(sch);
1252         if (ret != -EBUSY)
1253                 /* Subchannel is disabled, we're done. */
1254                 return;
1255         cdev->private->state = DEV_STATE_QUIESCE;
1256         if (cdev->handler)
1257                 cdev->handler(cdev, cdev->private->intparm,
1258                               ERR_PTR(-EIO));
1259         ret = ccw_device_cancel_halt_clear(cdev);
1260         if (ret == -EBUSY) {
1261                 ccw_device_set_timeout(cdev, HZ/10);
1262                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1263         }
1264         cio_disable_subchannel(sch);
1265 }
1266
1267 #ifdef CONFIG_CCW_CONSOLE
1268 static struct ccw_device console_cdev;
1269 static struct ccw_device_private console_private;
1270 static int console_cdev_in_use;
1271
1272 static DEFINE_SPINLOCK(ccw_console_lock);
1273
1274 spinlock_t * cio_get_console_lock(void)
1275 {
1276         return &ccw_console_lock;
1277 }
1278
1279 static int
1280 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1281 {
1282         int rc;
1283
1284         /* Initialize the ccw_device structure. */
1285         cdev->dev.parent= &sch->dev;
1286         rc = io_subchannel_recog(cdev, sch);
1287         if (rc)
1288                 return rc;
1289
1290         /* Now wait for the async. recognition to come to an end. */
1291         spin_lock_irq(cdev->ccwlock);
1292         while (!dev_fsm_final_state(cdev))
1293                 wait_cons_dev();
1294         rc = -EIO;
1295         if (cdev->private->state != DEV_STATE_OFFLINE)
1296                 goto out_unlock;
1297         ccw_device_online(cdev);
1298         while (!dev_fsm_final_state(cdev))
1299                 wait_cons_dev();
1300         if (cdev->private->state != DEV_STATE_ONLINE)
1301                 goto out_unlock;
1302         rc = 0;
1303 out_unlock:
1304         spin_unlock_irq(cdev->ccwlock);
1305         return 0;
1306 }
1307
1308 struct ccw_device *
1309 ccw_device_probe_console(void)
1310 {
1311         struct subchannel *sch;
1312         int ret;
1313
1314         if (xchg(&console_cdev_in_use, 1) != 0)
1315                 return ERR_PTR(-EBUSY);
1316         sch = cio_probe_console();
1317         if (IS_ERR(sch)) {
1318                 console_cdev_in_use = 0;
1319                 return (void *) sch;
1320         }
1321         memset(&console_cdev, 0, sizeof(struct ccw_device));
1322         memset(&console_private, 0, sizeof(struct ccw_device_private));
1323         console_cdev.private = &console_private;
1324         console_private.cdev = &console_cdev;
1325         ret = ccw_device_console_enable(&console_cdev, sch);
1326         if (ret) {
1327                 cio_release_console();
1328                 console_cdev_in_use = 0;
1329                 return ERR_PTR(ret);
1330         }
1331         console_cdev.online = 1;
1332         return &console_cdev;
1333 }
1334 #endif
1335
1336 /*
1337  * get ccw_device matching the busid, but only if owned by cdrv
1338  */
1339 static int
1340 __ccwdev_check_busid(struct device *dev, void *id)
1341 {
1342         char *bus_id;
1343
1344         bus_id = id;
1345
1346         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1347 }
1348
1349
1350 /**
1351  * get_ccwdev_by_busid() - obtain device from a bus id
1352  * @cdrv: driver the device is owned by
1353  * @bus_id: bus id of the device to be searched
1354  *
1355  * This function searches all devices owned by @cdrv for a device with a bus
1356  * id matching @bus_id.
1357  * Returns:
1358  *  If a match is found, its reference count of the found device is increased
1359  *  and it is returned; else %NULL is returned.
1360  */
1361 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1362                                        const char *bus_id)
1363 {
1364         struct device *dev;
1365         struct device_driver *drv;
1366
1367         drv = get_driver(&cdrv->driver);
1368         if (!drv)
1369                 return NULL;
1370
1371         dev = driver_find_device(drv, NULL, (void *)bus_id,
1372                                  __ccwdev_check_busid);
1373         put_driver(drv);
1374
1375         return dev ? to_ccwdev(dev) : NULL;
1376 }
1377
1378 /************************** device driver handling ************************/
1379
1380 /* This is the implementation of the ccw_driver class. The probe, remove
1381  * and release methods are initially very similar to the device_driver
1382  * implementations, with the difference that they have ccw_device
1383  * arguments.
1384  *
1385  * A ccw driver also contains the information that is needed for
1386  * device matching.
1387  */
1388 static int
1389 ccw_device_probe (struct device *dev)
1390 {
1391         struct ccw_device *cdev = to_ccwdev(dev);
1392         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1393         int ret;
1394
1395         cdev->drv = cdrv; /* to let the driver call _set_online */
1396
1397         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1398
1399         if (ret) {
1400                 cdev->drv = NULL;
1401                 return ret;
1402         }
1403
1404         return 0;
1405 }
1406
1407 static int
1408 ccw_device_remove (struct device *dev)
1409 {
1410         struct ccw_device *cdev = to_ccwdev(dev);
1411         struct ccw_driver *cdrv = cdev->drv;
1412         int ret;
1413
1414         if (cdrv->remove)
1415                 cdrv->remove(cdev);
1416         if (cdev->online) {
1417                 cdev->online = 0;
1418                 spin_lock_irq(cdev->ccwlock);
1419                 ret = ccw_device_offline(cdev);
1420                 spin_unlock_irq(cdev->ccwlock);
1421                 if (ret == 0)
1422                         wait_event(cdev->private->wait_q,
1423                                    dev_fsm_final_state(cdev));
1424                 else
1425                         //FIXME: we can't fail!
1426                         CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1427                                       "device 0.%x.%04x\n",
1428                                       ret, cdev->private->dev_id.ssid,
1429                                       cdev->private->dev_id.devno);
1430         }
1431         ccw_device_set_timeout(cdev, 0);
1432         cdev->drv = NULL;
1433         return 0;
1434 }
1435
1436 struct bus_type ccw_bus_type = {
1437         .name   = "ccw",
1438         .match  = ccw_bus_match,
1439         .uevent = ccw_uevent,
1440         .probe  = ccw_device_probe,
1441         .remove = ccw_device_remove,
1442 };
1443
1444 /**
1445  * ccw_driver_register() - register a ccw driver
1446  * @cdriver: driver to be registered
1447  *
1448  * This function is mainly a wrapper around driver_register().
1449  * Returns:
1450  *   %0 on success and a negative error value on failure.
1451  */
1452 int ccw_driver_register(struct ccw_driver *cdriver)
1453 {
1454         struct device_driver *drv = &cdriver->driver;
1455
1456         drv->bus = &ccw_bus_type;
1457         drv->name = cdriver->name;
1458
1459         return driver_register(drv);
1460 }
1461
1462 /**
1463  * ccw_driver_unregister() - deregister a ccw driver
1464  * @cdriver: driver to be deregistered
1465  *
1466  * This function is mainly a wrapper around driver_unregister().
1467  */
1468 void ccw_driver_unregister(struct ccw_driver *cdriver)
1469 {
1470         driver_unregister(&cdriver->driver);
1471 }
1472
1473 /* Helper func for qdio. */
1474 struct subchannel_id
1475 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1476 {
1477         struct subchannel *sch;
1478
1479         sch = to_subchannel(cdev->dev.parent);
1480         return sch->schid;
1481 }
1482
1483 MODULE_LICENSE("GPL");
1484 EXPORT_SYMBOL(ccw_device_set_online);
1485 EXPORT_SYMBOL(ccw_device_set_offline);
1486 EXPORT_SYMBOL(ccw_driver_register);
1487 EXPORT_SYMBOL(ccw_driver_unregister);
1488 EXPORT_SYMBOL(get_ccwdev_by_busid);
1489 EXPORT_SYMBOL(ccw_bus_type);
1490 EXPORT_SYMBOL(ccw_device_work);
1491 EXPORT_SYMBOL(ccw_device_notify_work);
1492 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);