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 #include <asm/cmb.h>
  25
  26 #include "cio.h"
  27 #include "cio_debug.h"
  28 #include "css.h"
  29 #include "device.h"
  30 #include "ioasm.h"
  31 #include "io_sch.h"
  32
  33 /******************* bus type handling ***********************/
  34
  35 /* The Linux driver model distinguishes between a bus type and
  36  * the bus itself. Of course we only have one channel
  37  * subsystem driver and one channel system per machine, but
  38  * we still use the abstraction. T.R. says it's a good idea. */
  39 static int
  40 ccw_bus_match (struct device * dev, struct device_driver * drv)
  41 {
  42         struct ccw_device *cdev = to_ccwdev(dev);
  43         struct ccw_driver *cdrv = to_ccwdrv(drv);
  44         const struct ccw_device_id *ids = cdrv->ids, *found;
  45
  46         if (!ids)
  47                 return 0;
  48
  49         found = ccw_device_id_match(ids, &cdev->id);
  50         if (!found)
  51                 return 0;
  52
  53         cdev->id.driver_info = found->driver_info;
  54
  55         return 1;
  56 }
  57
  58 /* Store modalias string delimited by prefix/suffix string into buffer with
  59  * specified size. Return length of resulting string (excluding trailing '\0')
  60  * even if string doesn't fit buffer (snprintf semantics). */
  61 static int snprint_alias(char *buf, size_t size,
  62                          struct ccw_device_id *id, const char *suffix)
  63 {
  64         int len;
  65
  66         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  67         if (len > size)
  68                 return len;
  69         buf += len;
  70         size -= len;
  71
  72         if (id->dev_type != 0)
  73                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  74                                 id->dev_model, suffix);
  75         else
  76                 len += snprintf(buf, size, "dtdm%s", suffix);
  77
  78         return len;
  79 }
  80
  81 /* Set up environment variables for ccw device uevent. Return 0 on success,
  82  * non-zero otherwise. */
  83 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  84 {
  85         struct ccw_device *cdev = to_ccwdev(dev);
  86         struct ccw_device_id *id = &(cdev->id);
  87         int ret;
  88         char modalias_buf[30];
  89
  90         /* CU_TYPE= */
  91         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
  92         if (ret)
  93                 return ret;
  94
  95         /* CU_MODEL= */
  96         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
  97         if (ret)
  98                 return ret;
  99
 100         /* The next two can be zero, that's ok for us */
 101         /* DEV_TYPE= */
 102         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 103         if (ret)
 104                 return ret;
 105
 106         /* DEV_MODEL= */
 107         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 108         if (ret)
 109                 return ret;
 110
 111         /* MODALIAS=  */
 112         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 113         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 114         return ret;
 115 }
 116
 117 struct bus_type ccw_bus_type;
 118
 119 static void io_subchannel_irq(struct subchannel *);
 120 static int io_subchannel_probe(struct subchannel *);
 121 static int io_subchannel_remove(struct subchannel *);
 122 static int io_subchannel_notify(struct subchannel *, int);
 123 static void io_subchannel_verify(struct subchannel *);
 124 static void io_subchannel_ioterm(struct subchannel *);
 125 static void io_subchannel_shutdown(struct subchannel *);
 126
 127 static struct css_driver io_subchannel_driver = {
 128         .owner = THIS_MODULE,
 129         .subchannel_type = SUBCHANNEL_TYPE_IO,
 130         .name = "io_subchannel",
 131         .irq = io_subchannel_irq,
 132         .notify = io_subchannel_notify,
 133         .verify = io_subchannel_verify,
 134         .termination = io_subchannel_ioterm,
 135         .probe = io_subchannel_probe,
 136         .remove = io_subchannel_remove,
 137         .shutdown = io_subchannel_shutdown,
 138 };
 139
 140 struct workqueue_struct *ccw_device_work;
 141 struct workqueue_struct *ccw_device_notify_work;
 142 wait_queue_head_t ccw_device_init_wq;
 143 atomic_t ccw_device_init_count;
 144
 145 static int __init
 146 init_ccw_bus_type (void)
 147 {
 148         int ret;
 149
 150         init_waitqueue_head(&ccw_device_init_wq);
 151         atomic_set(&ccw_device_init_count, 0);
 152
 153         ccw_device_work = create_singlethread_workqueue("cio");
 154         if (!ccw_device_work)
 155                 return -ENOMEM; /* FIXME: better errno ? */
 156         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 157         if (!ccw_device_notify_work) {
 158                 ret = -ENOMEM; /* FIXME: better errno ? */
 159                 goto out_err;
 160         }
 161         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 162         if (!slow_path_wq) {
 163                 ret = -ENOMEM; /* FIXME: better errno ? */
 164                 goto out_err;
 165         }
 166         if ((ret = bus_register (&ccw_bus_type)))
 167                 goto out_err;
 168
 169         ret = css_driver_register(&io_subchannel_driver);
 170         if (ret)
 171                 goto out_err;
 172
 173         wait_event(ccw_device_init_wq,
 174                    atomic_read(&ccw_device_init_count) == 0);
 175         flush_workqueue(ccw_device_work);
 176         return 0;
 177 out_err:
 178         if (ccw_device_work)
 179                 destroy_workqueue(ccw_device_work);
 180         if (ccw_device_notify_work)
 181                 destroy_workqueue(ccw_device_notify_work);
 182         if (slow_path_wq)
 183                 destroy_workqueue(slow_path_wq);
 184         return ret;
 185 }
 186
 187 static void __exit
 188 cleanup_ccw_bus_type (void)
 189 {
 190         css_driver_unregister(&io_subchannel_driver);
 191         bus_unregister(&ccw_bus_type);
 192         destroy_workqueue(ccw_device_notify_work);
 193         destroy_workqueue(ccw_device_work);
 194 }
 195
 196 subsys_initcall(init_ccw_bus_type);
 197 module_exit(cleanup_ccw_bus_type);
 198
 199 /************************ device handling **************************/
 200
 201 /*
 202  * A ccw_device has some interfaces in sysfs in addition to the
 203  * standard ones.
 204  * The following entries are designed to export the information which
 205  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 206  * are obvious, so they don't have an entry :)
 207  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 208  */
 209 static ssize_t
 210 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 211 {
 212         struct subchannel *sch = to_subchannel(dev);
 213         struct chsc_ssd_info *ssd = &sch->ssd_info;
 214         ssize_t ret = 0;
 215         int chp;
 216         int mask;
 217
 218         for (chp = 0; chp < 8; chp++) {
 219                 mask = 0x80 >> chp;
 220                 if (ssd->path_mask & mask)
 221                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 222                 else
 223                         ret += sprintf(buf + ret, "00 ");
 224         }
 225         ret += sprintf (buf+ret, "\n");
 226         return min((ssize_t)PAGE_SIZE, ret);
 227 }
 228
 229 static ssize_t
 230 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 231 {
 232         struct subchannel *sch = to_subchannel(dev);
 233         struct pmcw *pmcw = &sch->schib.pmcw;
 234
 235         return sprintf (buf, "%02x %02x %02x\n",
 236                         pmcw->pim, pmcw->pam, pmcw->pom);
 237 }
 238
 239 static ssize_t
 240 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 241 {
 242         struct ccw_device *cdev = to_ccwdev(dev);
 243         struct ccw_device_id *id = &(cdev->id);
 244
 245         if (id->dev_type != 0)
 246                 return sprintf(buf, "%04x/%02x\n",
 247                                 id->dev_type, id->dev_model);
 248         else
 249                 return sprintf(buf, "n/a\n");
 250 }
 251
 252 static ssize_t
 253 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 254 {
 255         struct ccw_device *cdev = to_ccwdev(dev);
 256         struct ccw_device_id *id = &(cdev->id);
 257
 258         return sprintf(buf, "%04x/%02x\n",
 259                        id->cu_type, id->cu_model);
 260 }
 261
 262 static ssize_t
 263 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 264 {
 265         struct ccw_device *cdev = to_ccwdev(dev);
 266         struct ccw_device_id *id = &(cdev->id);
 267         int len;
 268
 269         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 270
 271         return len > PAGE_SIZE ? PAGE_SIZE : len;
 272 }
 273
 274 static ssize_t
 275 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 276 {
 277         struct ccw_device *cdev = to_ccwdev(dev);
 278
 279         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 280 }
 281
 282 int ccw_device_is_orphan(struct ccw_device *cdev)
 283 {
 284         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 285 }
 286
 287 static void ccw_device_unregister(struct ccw_device *cdev)
 288 {
 289         if (test_and_clear_bit(1, &cdev->private->registered))
 290                 device_del(&cdev->dev);
 291 }
 292
 293 static void ccw_device_remove_orphan_cb(struct device *dev)
 294 {
 295         struct ccw_device *cdev = to_ccwdev(dev);
 296
 297         ccw_device_unregister(cdev);
 298         put_device(&cdev->dev);
 299 }
 300
 301 static void ccw_device_remove_sch_cb(struct device *dev)
 302 {
 303         struct subchannel *sch;
 304
 305         sch = to_subchannel(dev);
 306         css_sch_device_unregister(sch);
 307         /* Reset intparm to zeroes. */
 308         sch->schib.pmcw.intparm = 0;
 309         cio_modify(sch);
 310         put_device(&sch->dev);
 311 }
 312
 313 static void
 314 ccw_device_remove_disconnected(struct ccw_device *cdev)
 315 {
 316         unsigned long flags;
 317         int rc;
 318
 319         /*
 320          * Forced offline in disconnected state means
 321          * 'throw away device'.
 322          */
 323         if (ccw_device_is_orphan(cdev)) {
 324                 /*
 325                  * Deregister ccw device.
 326                  * Unfortunately, we cannot do this directly from the
 327                  * attribute method.
 328                  */
 329                 spin_lock_irqsave(cdev->ccwlock, flags);
 330                 cdev->private->state = DEV_STATE_NOT_OPER;
 331                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 332                 rc = device_schedule_callback(&cdev->dev,
 333                                               ccw_device_remove_orphan_cb);
 334                 if (rc)
 335                         CIO_MSG_EVENT(2, "Couldn't unregister orphan "
 336                                       "0.%x.%04x\n",
 337                                       cdev->private->dev_id.ssid,
 338                                       cdev->private->dev_id.devno);
 339                 return;
 340         }
 341         /* Deregister subchannel, which will kill the ccw device. */
 342         rc = device_schedule_callback(cdev->dev.parent,
 343                                       ccw_device_remove_sch_cb);
 344         if (rc)
 345                 CIO_MSG_EVENT(2, "Couldn't unregister disconnected device "
 346                               "0.%x.%04x\n",
 347                               cdev->private->dev_id.ssid,
 348                               cdev->private->dev_id.devno);
 349 }
 350
 351 /**
 352  * ccw_device_set_offline() - disable a ccw device for I/O
 353  * @cdev: target ccw device
 354  *
 355  * This function calls the driver's set_offline() function for @cdev, if
 356  * given, and then disables @cdev.
 357  * Returns:
 358  *   %0 on success and a negative error value on failure.
 359  * Context:
 360  *  enabled, ccw device lock not held
 361  */
 362 int ccw_device_set_offline(struct ccw_device *cdev)
 363 {
 364         int ret;
 365
 366         if (!cdev)
 367                 return -ENODEV;
 368         if (!cdev->online || !cdev->drv)
 369                 return -EINVAL;
 370
 371         if (cdev->drv->set_offline) {
 372                 ret = cdev->drv->set_offline(cdev);
 373                 if (ret != 0)
 374                         return ret;
 375         }
 376         cdev->online = 0;
 377         spin_lock_irq(cdev->ccwlock);
 378         ret = ccw_device_offline(cdev);
 379         if (ret == -ENODEV) {
 380                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 381                         cdev->private->state = DEV_STATE_OFFLINE;
 382                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 383                 }
 384                 spin_unlock_irq(cdev->ccwlock);
 385                 return ret;
 386         }
 387         spin_unlock_irq(cdev->ccwlock);
 388         if (ret == 0)
 389                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 390         else {
 391                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 392                               "device 0.%x.%04x\n",
 393                               ret, cdev->private->dev_id.ssid,
 394                               cdev->private->dev_id.devno);
 395                 cdev->online = 1;
 396         }
 397         return ret;
 398 }
 399
 400 /**
 401  * ccw_device_set_online() - enable a ccw device for I/O
 402  * @cdev: target ccw device
 403  *
 404  * This function first enables @cdev and then calls the driver's set_online()
 405  * function for @cdev, if given. If set_online() returns an error, @cdev is
 406  * disabled again.
 407  * Returns:
 408  *   %0 on success and a negative error value on failure.
 409  * Context:
 410  *  enabled, ccw device lock not held
 411  */
 412 int ccw_device_set_online(struct ccw_device *cdev)
 413 {
 414         int ret;
 415
 416         if (!cdev)
 417                 return -ENODEV;
 418         if (cdev->online || !cdev->drv)
 419                 return -EINVAL;
 420
 421         spin_lock_irq(cdev->ccwlock);
 422         ret = ccw_device_online(cdev);
 423         spin_unlock_irq(cdev->ccwlock);
 424         if (ret == 0)
 425                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 426         else {
 427                 CIO_MSG_EVENT(2, "ccw_device_online returned %d, "
 428                               "device 0.%x.%04x\n",
 429                               ret, cdev->private->dev_id.ssid,
 430                               cdev->private->dev_id.devno);
 431                 return ret;
 432         }
 433         if (cdev->private->state != DEV_STATE_ONLINE)
 434                 return -ENODEV;
 435         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 436                 cdev->online = 1;
 437                 return 0;
 438         }
 439         spin_lock_irq(cdev->ccwlock);
 440         ret = ccw_device_offline(cdev);
 441         spin_unlock_irq(cdev->ccwlock);
 442         if (ret == 0)
 443                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 444         else
 445                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 446                               "device 0.%x.%04x\n",
 447                               ret, cdev->private->dev_id.ssid,
 448                               cdev->private->dev_id.devno);
 449         return (ret == 0) ? -ENODEV : ret;
 450 }
 451
 452 static void online_store_handle_offline(struct ccw_device *cdev)
 453 {
 454         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 455                 ccw_device_remove_disconnected(cdev);
 456         else if (cdev->drv && cdev->drv->set_offline)
 457                 ccw_device_set_offline(cdev);
 458 }
 459
 460 static int online_store_recog_and_online(struct ccw_device *cdev)
 461 {
 462         int ret;
 463
 464         /* Do device recognition, if needed. */
 465         if (cdev->id.cu_type == 0) {
 466                 ret = ccw_device_recognition(cdev);
 467                 if (ret) {
 468                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 469                                       "for device 0.%x.%04x (ret=%d)\n",
 470                                       cdev->private->dev_id.ssid,
 471                                       cdev->private->dev_id.devno, ret);
 472                         return ret;
 473                 }
 474                 wait_event(cdev->private->wait_q,
 475                            cdev->private->flags.recog_done);
 476         }
 477         if (cdev->drv && cdev->drv->set_online)
 478                 ccw_device_set_online(cdev);
 479         return 0;
 480 }
 481 static void online_store_handle_online(struct ccw_device *cdev, int force)
 482 {
 483         int ret;
 484
 485         ret = online_store_recog_and_online(cdev);
 486         if (ret)
 487                 return;
 488         if (force && cdev->private->state == DEV_STATE_BOXED) {
 489                 ret = ccw_device_stlck(cdev);
 490                 if (ret) {
 491                         dev_warn(&cdev->dev,
 492                                  "ccw_device_stlck returned %d!\n", ret);
 493                         return;
 494                 }
 495                 if (cdev->id.cu_type == 0)
 496                         cdev->private->state = DEV_STATE_NOT_OPER;
 497                 online_store_recog_and_online(cdev);
 498         }
 499
 500 }
 501
 502 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 503                              const char *buf, size_t count)
 504 {
 505         struct ccw_device *cdev = to_ccwdev(dev);
 506         int i, force;
 507         char *tmp;
 508
 509         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 510                 return -EAGAIN;
 511
 512         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 513                 atomic_set(&cdev->private->onoff, 0);
 514                 return -EINVAL;
 515         }
 516         if (!strncmp(buf, "force\n", count)) {
 517                 force = 1;
 518                 i = 1;
 519         } else {
 520                 force = 0;
 521                 i = simple_strtoul(buf, &tmp, 16);
 522         }
 523
 524         switch (i) {
 525         case 0:
 526                 online_store_handle_offline(cdev);
 527                 break;
 528         case 1:
 529                 online_store_handle_online(cdev, force);
 530                 break;
 531         default:
 532                 count = -EINVAL;
 533         }
 534         if (cdev->drv)
 535                 module_put(cdev->drv->owner);
 536         atomic_set(&cdev->private->onoff, 0);
 537         return count;
 538 }
 539
 540 static ssize_t
 541 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 542 {
 543         struct ccw_device *cdev = to_ccwdev(dev);
 544         struct subchannel *sch;
 545
 546         if (ccw_device_is_orphan(cdev))
 547                 return sprintf(buf, "no device\n");
 548         switch (cdev->private->state) {
 549         case DEV_STATE_BOXED:
 550                 return sprintf(buf, "boxed\n");
 551         case DEV_STATE_DISCONNECTED:
 552         case DEV_STATE_DISCONNECTED_SENSE_ID:
 553         case DEV_STATE_NOT_OPER:
 554                 sch = to_subchannel(dev->parent);
 555                 if (!sch->lpm)
 556                         return sprintf(buf, "no path\n");
 557                 else
 558                         return sprintf(buf, "no device\n");
 559         default:
 560                 /* All other states considered fine. */
 561                 return sprintf(buf, "good\n");
 562         }
 563 }
 564
 565 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 566 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 567 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 568 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 569 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 570 static DEVICE_ATTR(online, 0644, online_show, online_store);
 571 extern struct device_attribute dev_attr_cmb_enable;
 572 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 573
 574 static struct attribute * subch_attrs[] = {
 575         &dev_attr_chpids.attr,
 576         &dev_attr_pimpampom.attr,
 577         NULL,
 578 };
 579
 580 static struct attribute_group subch_attr_group = {
 581         .attrs = subch_attrs,
 582 };
 583
 584 struct attribute_group *subch_attr_groups[] = {
 585         &subch_attr_group,
 586         NULL,
 587 };
 588
 589 static struct attribute * ccwdev_attrs[] = {
 590         &dev_attr_devtype.attr,
 591         &dev_attr_cutype.attr,
 592         &dev_attr_modalias.attr,
 593         &dev_attr_online.attr,
 594         &dev_attr_cmb_enable.attr,
 595         &dev_attr_availability.attr,
 596         NULL,
 597 };
 598
 599 static struct attribute_group ccwdev_attr_group = {
 600         .attrs = ccwdev_attrs,
 601 };
 602
 603 static struct attribute_group *ccwdev_attr_groups[] = {
 604         &ccwdev_attr_group,
 605         NULL,
 606 };
 607
 608 /* this is a simple abstraction for device_register that sets the
 609  * correct bus type and adds the bus specific files */
 610 static int ccw_device_register(struct ccw_device *cdev)
 611 {
 612         struct device *dev = &cdev->dev;
 613         int ret;
 614
 615         dev->bus = &ccw_bus_type;
 616
 617         if ((ret = device_add(dev)))
 618                 return ret;
 619
 620         set_bit(1, &cdev->private->registered);
 621         return ret;
 622 }
 623
 624 struct match_data {
 625         struct ccw_dev_id dev_id;
 626         struct ccw_device * sibling;
 627 };
 628
 629 static int
 630 match_devno(struct device * dev, void * data)
 631 {
 632         struct match_data * d = data;
 633         struct ccw_device * cdev;
 634
 635         cdev = to_ccwdev(dev);
 636         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 637             !ccw_device_is_orphan(cdev) &&
 638             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 639             (cdev != d->sibling))
 640                 return 1;
 641         return 0;
 642 }
 643
 644 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 645                                                      struct ccw_device *sibling)
 646 {
 647         struct device *dev;
 648         struct match_data data;
 649
 650         data.dev_id = *dev_id;
 651         data.sibling = sibling;
 652         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 653
 654         return dev ? to_ccwdev(dev) : NULL;
 655 }
 656
 657 static int match_orphan(struct device *dev, void *data)
 658 {
 659         struct ccw_dev_id *dev_id;
 660         struct ccw_device *cdev;
 661
 662         dev_id = data;
 663         cdev = to_ccwdev(dev);
 664         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 665 }
 666
 667 static struct ccw_device *
 668 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 669                               struct ccw_dev_id *dev_id)
 670 {
 671         struct device *dev;
 672
 673         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 674                                 match_orphan);
 675
 676         return dev ? to_ccwdev(dev) : NULL;
 677 }
 678
 679 static void
 680 ccw_device_add_changed(struct work_struct *work)
 681 {
 682         struct ccw_device_private *priv;
 683         struct ccw_device *cdev;
 684
 685         priv = container_of(work, struct ccw_device_private, kick_work);
 686         cdev = priv->cdev;
 687         if (device_add(&cdev->dev)) {
 688                 put_device(&cdev->dev);
 689                 return;
 690         }
 691         set_bit(1, &cdev->private->registered);
 692 }
 693
 694 void ccw_device_do_unreg_rereg(struct work_struct *work)
 695 {
 696         struct ccw_device_private *priv;
 697         struct ccw_device *cdev;
 698         struct subchannel *sch;
 699
 700         priv = container_of(work, struct ccw_device_private, kick_work);
 701         cdev = priv->cdev;
 702         sch = to_subchannel(cdev->dev.parent);
 703
 704         ccw_device_unregister(cdev);
 705         PREPARE_WORK(&cdev->private->kick_work,
 706                      ccw_device_add_changed);
 707         queue_work(ccw_device_work, &cdev->private->kick_work);
 708 }
 709
 710 static void
 711 ccw_device_release(struct device *dev)
 712 {
 713         struct ccw_device *cdev;
 714
 715         cdev = to_ccwdev(dev);
 716         kfree(cdev->private);
 717         kfree(cdev);
 718 }
 719
 720 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 721 {
 722         struct ccw_device *cdev;
 723
 724         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 725         if (cdev) {
 726                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 727                                         GFP_KERNEL | GFP_DMA);
 728                 if (cdev->private)
 729                         return cdev;
 730         }
 731         kfree(cdev);
 732         return ERR_PTR(-ENOMEM);
 733 }
 734
 735 static int io_subchannel_initialize_dev(struct subchannel *sch,
 736                                         struct ccw_device *cdev)
 737 {
 738         cdev->private->cdev = cdev;
 739         atomic_set(&cdev->private->onoff, 0);
 740         cdev->dev.parent = &sch->dev;
 741         cdev->dev.release = ccw_device_release;
 742         INIT_WORK(&cdev->private->kick_work, NULL);
 743         cdev->dev.groups = ccwdev_attr_groups;
 744         /* Do first half of device_register. */
 745         device_initialize(&cdev->dev);
 746         if (!get_device(&sch->dev)) {
 747                 if (cdev->dev.release)
 748                         cdev->dev.release(&cdev->dev);
 749                 return -ENODEV;
 750         }
 751         return 0;
 752 }
 753
 754 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 755 {
 756         struct ccw_device *cdev;
 757         int ret;
 758
 759         cdev = io_subchannel_allocate_dev(sch);
 760         if (!IS_ERR(cdev)) {
 761                 ret = io_subchannel_initialize_dev(sch, cdev);
 762                 if (ret) {
 763                         kfree(cdev);
 764                         cdev = ERR_PTR(ret);
 765                 }
 766         }
 767         return cdev;
 768 }
 769
 770 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 771
 772 static void sch_attach_device(struct subchannel *sch,
 773                               struct ccw_device *cdev)
 774 {
 775         css_update_ssd_info(sch);
 776         spin_lock_irq(sch->lock);
 777         sch_set_cdev(sch, cdev);
 778         cdev->private->schid = sch->schid;
 779         cdev->ccwlock = sch->lock;
 780         device_trigger_reprobe(sch);
 781         spin_unlock_irq(sch->lock);
 782 }
 783
 784 static void sch_attach_disconnected_device(struct subchannel *sch,
 785                                            struct ccw_device *cdev)
 786 {
 787         struct subchannel *other_sch;
 788         int ret;
 789
 790         other_sch = to_subchannel(get_device(cdev->dev.parent));
 791         ret = device_move(&cdev->dev, &sch->dev);
 792         if (ret) {
 793                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
 794                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 795                               cdev->private->dev_id.devno, ret);
 796                 put_device(&other_sch->dev);
 797                 return;
 798         }
 799         sch_set_cdev(other_sch, NULL);
 800         /* No need to keep a subchannel without ccw device around. */
 801         css_sch_device_unregister(other_sch);
 802         put_device(&other_sch->dev);
 803         sch_attach_device(sch, cdev);
 804 }
 805
 806 static void sch_attach_orphaned_device(struct subchannel *sch,
 807                                        struct ccw_device *cdev)
 808 {
 809         int ret;
 810
 811         /* Try to move the ccw device to its new subchannel. */
 812         ret = device_move(&cdev->dev, &sch->dev);
 813         if (ret) {
 814                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 815                               "failed (ret=%d)!\n",
 816                               cdev->private->dev_id.ssid,
 817                               cdev->private->dev_id.devno, ret);
 818                 return;
 819         }
 820         sch_attach_device(sch, cdev);
 821 }
 822
 823 static void sch_create_and_recog_new_device(struct subchannel *sch)
 824 {
 825         struct ccw_device *cdev;
 826
 827         /* Need to allocate a new ccw device. */
 828         cdev = io_subchannel_create_ccwdev(sch);
 829         if (IS_ERR(cdev)) {
 830                 /* OK, we did everything we could... */
 831                 css_sch_device_unregister(sch);
 832                 return;
 833         }
 834         spin_lock_irq(sch->lock);
 835         sch_set_cdev(sch, cdev);
 836         spin_unlock_irq(sch->lock);
 837         /* Start recognition for the new ccw device. */
 838         if (io_subchannel_recog(cdev, sch)) {
 839                 spin_lock_irq(sch->lock);
 840                 sch_set_cdev(sch, NULL);
 841                 spin_unlock_irq(sch->lock);
 842                 if (cdev->dev.release)
 843                         cdev->dev.release(&cdev->dev);
 844                 css_sch_device_unregister(sch);
 845         }
 846 }
 847
 848
 849 void ccw_device_move_to_orphanage(struct work_struct *work)
 850 {
 851         struct ccw_device_private *priv;
 852         struct ccw_device *cdev;
 853         struct ccw_device *replacing_cdev;
 854         struct subchannel *sch;
 855         int ret;
 856         struct channel_subsystem *css;
 857         struct ccw_dev_id dev_id;
 858
 859         priv = container_of(work, struct ccw_device_private, kick_work);
 860         cdev = priv->cdev;
 861         sch = to_subchannel(cdev->dev.parent);
 862         css = to_css(sch->dev.parent);
 863         dev_id.devno = sch->schib.pmcw.dev;
 864         dev_id.ssid = sch->schid.ssid;
 865
 866         /*
 867          * Move the orphaned ccw device to the orphanage so the replacing
 868          * ccw device can take its place on the subchannel.
 869          */
 870         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 871         if (ret) {
 872                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 873                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 874                               cdev->private->dev_id.devno, ret);
 875                 return;
 876         }
 877         cdev->ccwlock = css->pseudo_subchannel->lock;
 878         /*
 879          * Search for the replacing ccw device
 880          * - among the disconnected devices
 881          * - in the orphanage
 882          */
 883         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 884         if (replacing_cdev) {
 885                 sch_attach_disconnected_device(sch, replacing_cdev);
 886                 return;
 887         }
 888         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 889         if (replacing_cdev) {
 890                 sch_attach_orphaned_device(sch, replacing_cdev);
 891                 return;
 892         }
 893         sch_create_and_recog_new_device(sch);
 894 }
 895
 896 /*
 897  * Register recognized device.
 898  */
 899 static void
 900 io_subchannel_register(struct work_struct *work)
 901 {
 902         struct ccw_device_private *priv;
 903         struct ccw_device *cdev;
 904         struct subchannel *sch;
 905         int ret;
 906         unsigned long flags;
 907
 908         priv = container_of(work, struct ccw_device_private, kick_work);
 909         cdev = priv->cdev;
 910         sch = to_subchannel(cdev->dev.parent);
 911         css_update_ssd_info(sch);
 912         /*
 913          * io_subchannel_register() will also be called after device
 914          * recognition has been done for a boxed device (which will already
 915          * be registered). We need to reprobe since we may now have sense id
 916          * information.
 917          */
 918         if (klist_node_attached(&cdev->dev.knode_parent)) {
 919                 if (!cdev->drv) {
 920                         ret = device_reprobe(&cdev->dev);
 921                         if (ret)
 922                                 /* We can't do much here. */
 923                                 CIO_MSG_EVENT(2, "device_reprobe() returned"
 924                                               " %d for 0.%x.%04x\n", ret,
 925                                               cdev->private->dev_id.ssid,
 926                                               cdev->private->dev_id.devno);
 927                 }
 928                 goto out;
 929         }
 930         /*
 931          * Now we know this subchannel will stay, we can throw
 932          * our delayed uevent.
 933          */
 934         sch->dev.uevent_suppress = 0;
 935         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 936         /* make it known to the system */
 937         ret = ccw_device_register(cdev);
 938         if (ret) {
 939                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 940                               cdev->private->dev_id.ssid,
 941                               cdev->private->dev_id.devno, ret);
 942                 put_device(&cdev->dev);
 943                 spin_lock_irqsave(sch->lock, flags);
 944                 sch_set_cdev(sch, NULL);
 945                 spin_unlock_irqrestore(sch->lock, flags);
 946                 kfree (cdev->private);
 947                 kfree (cdev);
 948                 put_device(&sch->dev);
 949                 if (atomic_dec_and_test(&ccw_device_init_count))
 950                         wake_up(&ccw_device_init_wq);
 951                 return;
 952         }
 953         put_device(&cdev->dev);
 954 out:
 955         cdev->private->flags.recog_done = 1;
 956         put_device(&sch->dev);
 957         wake_up(&cdev->private->wait_q);
 958         if (atomic_dec_and_test(&ccw_device_init_count))
 959                 wake_up(&ccw_device_init_wq);
 960 }
 961
 962 static void ccw_device_call_sch_unregister(struct work_struct *work)
 963 {
 964         struct ccw_device_private *priv;
 965         struct ccw_device *cdev;
 966         struct subchannel *sch;
 967
 968         priv = container_of(work, struct ccw_device_private, kick_work);
 969         cdev = priv->cdev;
 970         sch = to_subchannel(cdev->dev.parent);
 971         css_sch_device_unregister(sch);
 972         /* Reset intparm to zeroes. */
 973         sch->schib.pmcw.intparm = 0;
 974         cio_modify(sch);
 975         put_device(&cdev->dev);
 976         put_device(&sch->dev);
 977 }
 978
 979 /*
 980  * subchannel recognition done. Called from the state machine.
 981  */
 982 void
 983 io_subchannel_recog_done(struct ccw_device *cdev)
 984 {
 985         struct subchannel *sch;
 986
 987         if (css_init_done == 0) {
 988                 cdev->private->flags.recog_done = 1;
 989                 return;
 990         }
 991         switch (cdev->private->state) {
 992         case DEV_STATE_NOT_OPER:
 993                 cdev->private->flags.recog_done = 1;
 994                 /* Remove device found not operational. */
 995                 if (!get_device(&cdev->dev))
 996                         break;
 997                 sch = to_subchannel(cdev->dev.parent);
 998                 PREPARE_WORK(&cdev->private->kick_work,
 999                              ccw_device_call_sch_unregister);
1000                 queue_work(slow_path_wq, &cdev->private->kick_work);
1001                 if (atomic_dec_and_test(&ccw_device_init_count))
1002                         wake_up(&ccw_device_init_wq);
1003                 break;
1004         case DEV_STATE_BOXED:
1005                 /* Device did not respond in time. */
1006         case DEV_STATE_OFFLINE:
1007                 /*
1008                  * We can't register the device in interrupt context so
1009                  * we schedule a work item.
1010                  */
1011                 if (!get_device(&cdev->dev))
1012                         break;
1013                 PREPARE_WORK(&cdev->private->kick_work,
1014                              io_subchannel_register);
1015                 queue_work(slow_path_wq, &cdev->private->kick_work);
1016                 break;
1017         }
1018 }
1019
1020 static int
1021 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1022 {
1023         int rc;
1024         struct ccw_device_private *priv;
1025
1026         sch_set_cdev(sch, cdev);
1027         sch->driver = &io_subchannel_driver;
1028         cdev->ccwlock = sch->lock;
1029
1030         /* Init private data. */
1031         priv = cdev->private;
1032         priv->dev_id.devno = sch->schib.pmcw.dev;
1033         priv->dev_id.ssid = sch->schid.ssid;
1034         priv->schid = sch->schid;
1035         priv->state = DEV_STATE_NOT_OPER;
1036         INIT_LIST_HEAD(&priv->cmb_list);
1037         init_waitqueue_head(&priv->wait_q);
1038         init_timer(&priv->timer);
1039
1040         /* Set an initial name for the device. */
1041         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1042                   sch->schid.ssid, sch->schib.pmcw.dev);
1043
1044         /* Increase counter of devices currently in recognition. */
1045         atomic_inc(&ccw_device_init_count);
1046
1047         /* Start async. device sensing. */
1048         spin_lock_irq(sch->lock);
1049         rc = ccw_device_recognition(cdev);
1050         spin_unlock_irq(sch->lock);
1051         if (rc) {
1052                 if (atomic_dec_and_test(&ccw_device_init_count))
1053                         wake_up(&ccw_device_init_wq);
1054         }
1055         return rc;
1056 }
1057
1058 static void ccw_device_move_to_sch(struct work_struct *work)
1059 {
1060         struct ccw_device_private *priv;
1061         int rc;
1062         struct subchannel *sch;
1063         struct ccw_device *cdev;
1064         struct subchannel *former_parent;
1065
1066         priv = container_of(work, struct ccw_device_private, kick_work);
1067         sch = priv->sch;
1068         cdev = priv->cdev;
1069         former_parent = ccw_device_is_orphan(cdev) ?
1070                 NULL : to_subchannel(get_device(cdev->dev.parent));
1071         mutex_lock(&sch->reg_mutex);
1072         /* Try to move the ccw device to its new subchannel. */
1073         rc = device_move(&cdev->dev, &sch->dev);
1074         mutex_unlock(&sch->reg_mutex);
1075         if (rc) {
1076                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1077                               "0.%x.%04x failed (ret=%d)!\n",
1078                               cdev->private->dev_id.ssid,
1079                               cdev->private->dev_id.devno, sch->schid.ssid,
1080                               sch->schid.sch_no, rc);
1081                 css_sch_device_unregister(sch);
1082                 goto out;
1083         }
1084         if (former_parent) {
1085                 spin_lock_irq(former_parent->lock);
1086                 sch_set_cdev(former_parent, NULL);
1087                 spin_unlock_irq(former_parent->lock);
1088                 css_sch_device_unregister(former_parent);
1089                 /* Reset intparm to zeroes. */
1090                 former_parent->schib.pmcw.intparm = 0;
1091                 cio_modify(former_parent);
1092         }
1093         sch_attach_device(sch, cdev);
1094 out:
1095         if (former_parent)
1096                 put_device(&former_parent->dev);
1097         put_device(&cdev->dev);
1098 }
1099
1100 static void io_subchannel_irq(struct subchannel *sch)
1101 {
1102         struct ccw_device *cdev;
1103
1104         cdev = sch_get_cdev(sch);
1105
1106         CIO_TRACE_EVENT(3, "IRQ");
1107         CIO_TRACE_EVENT(3, sch->dev.bus_id);
1108         if (cdev)
1109                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1110 }
1111
1112 static int
1113 io_subchannel_probe (struct subchannel *sch)
1114 {
1115         struct ccw_device *cdev;
1116         int rc;
1117         unsigned long flags;
1118         struct ccw_dev_id dev_id;
1119
1120         cdev = sch_get_cdev(sch);
1121         if (cdev) {
1122                 /*
1123                  * This subchannel already has an associated ccw_device.
1124                  * Register it and exit. This happens for all early
1125                  * device, e.g. the console.
1126                  */
1127                 cdev->dev.groups = ccwdev_attr_groups;
1128                 device_initialize(&cdev->dev);
1129                 ccw_device_register(cdev);
1130                 /*
1131                  * Check if the device is already online. If it is
1132                  * the reference count needs to be corrected
1133                  * (see ccw_device_online and css_init_done for the
1134                  * ugly details).
1135                  */
1136                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1137                     cdev->private->state != DEV_STATE_OFFLINE &&
1138                     cdev->private->state != DEV_STATE_BOXED)
1139                         get_device(&cdev->dev);
1140                 return 0;
1141         }
1142         /*
1143          * First check if a fitting device may be found amongst the
1144          * disconnected devices or in the orphanage.
1145          */
1146         dev_id.devno = sch->schib.pmcw.dev;
1147         dev_id.ssid = sch->schid.ssid;
1148         /* Allocate I/O subchannel private data. */
1149         sch->private = kzalloc(sizeof(struct io_subchannel_private),
1150                                GFP_KERNEL | GFP_DMA);
1151         if (!sch->private)
1152                 return -ENOMEM;
1153         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1154         if (!cdev)
1155                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1156                                                      &dev_id);
1157         if (cdev) {
1158                 /*
1159                  * Schedule moving the device until when we have a registered
1160                  * subchannel to move to and succeed the probe. We can
1161                  * unregister later again, when the probe is through.
1162                  */
1163                 cdev->private->sch = sch;
1164                 PREPARE_WORK(&cdev->private->kick_work,
1165                              ccw_device_move_to_sch);
1166                 queue_work(slow_path_wq, &cdev->private->kick_work);
1167                 return 0;
1168         }
1169         cdev = io_subchannel_create_ccwdev(sch);
1170         if (IS_ERR(cdev)) {
1171                 kfree(sch->private);
1172                 return PTR_ERR(cdev);
1173         }
1174         rc = io_subchannel_recog(cdev, sch);
1175         if (rc) {
1176                 spin_lock_irqsave(sch->lock, flags);
1177                 sch_set_cdev(sch, NULL);
1178                 spin_unlock_irqrestore(sch->lock, flags);
1179                 if (cdev->dev.release)
1180                         cdev->dev.release(&cdev->dev);
1181                 kfree(sch->private);
1182         }
1183
1184         return rc;
1185 }
1186
1187 static int
1188 io_subchannel_remove (struct subchannel *sch)
1189 {
1190         struct ccw_device *cdev;
1191         unsigned long flags;
1192
1193         cdev = sch_get_cdev(sch);
1194         if (!cdev)
1195                 return 0;
1196         /* Set ccw device to not operational and drop reference. */
1197         spin_lock_irqsave(cdev->ccwlock, flags);
1198         sch_set_cdev(sch, NULL);
1199         cdev->private->state = DEV_STATE_NOT_OPER;
1200         spin_unlock_irqrestore(cdev->ccwlock, flags);
1201         ccw_device_unregister(cdev);
1202         put_device(&cdev->dev);
1203         kfree(sch->private);
1204         return 0;
1205 }
1206
1207 static int io_subchannel_notify(struct subchannel *sch, int event)
1208 {
1209         struct ccw_device *cdev;
1210
1211         cdev = sch_get_cdev(sch);
1212         if (!cdev)
1213                 return 0;
1214         if (!cdev->drv)
1215                 return 0;
1216         if (!cdev->online)
1217                 return 0;
1218         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1219 }
1220
1221 static void io_subchannel_verify(struct subchannel *sch)
1222 {
1223         struct ccw_device *cdev;
1224
1225         cdev = sch_get_cdev(sch);
1226         if (cdev)
1227                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1228 }
1229
1230 static void io_subchannel_ioterm(struct subchannel *sch)
1231 {
1232         struct ccw_device *cdev;
1233
1234         cdev = sch_get_cdev(sch);
1235         if (!cdev)
1236                 return;
1237         /* Internal I/O will be retried by the interrupt handler. */
1238         if (cdev->private->flags.intretry)
1239                 return;
1240         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1241         if (cdev->handler)
1242                 cdev->handler(cdev, cdev->private->intparm,
1243                               ERR_PTR(-EIO));
1244 }
1245
1246 static void
1247 io_subchannel_shutdown(struct subchannel *sch)
1248 {
1249         struct ccw_device *cdev;
1250         int ret;
1251
1252         cdev = sch_get_cdev(sch);
1253
1254         if (cio_is_console(sch->schid))
1255                 return;
1256         if (!sch->schib.pmcw.ena)
1257                 /* Nothing to do. */
1258                 return;
1259         ret = cio_disable_subchannel(sch);
1260         if (ret != -EBUSY)
1261                 /* Subchannel is disabled, we're done. */
1262                 return;
1263         cdev->private->state = DEV_STATE_QUIESCE;
1264         if (cdev->handler)
1265                 cdev->handler(cdev, cdev->private->intparm,
1266                               ERR_PTR(-EIO));
1267         ret = ccw_device_cancel_halt_clear(cdev);
1268         if (ret == -EBUSY) {
1269                 ccw_device_set_timeout(cdev, HZ/10);
1270                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1271         }
1272         cio_disable_subchannel(sch);
1273 }
1274
1275 #ifdef CONFIG_CCW_CONSOLE
1276 static struct ccw_device console_cdev;
1277 static struct ccw_device_private console_private;
1278 static int console_cdev_in_use;
1279
1280 static DEFINE_SPINLOCK(ccw_console_lock);
1281
1282 spinlock_t * cio_get_console_lock(void)
1283 {
1284         return &ccw_console_lock;
1285 }
1286
1287 static int
1288 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1289 {
1290         int rc;
1291
1292         /* Attach subchannel private data. */
1293         sch->private = cio_get_console_priv();
1294         memset(sch->private, 0, sizeof(struct io_subchannel_private));
1295         /* Initialize the ccw_device structure. */
1296         cdev->dev.parent= &sch->dev;
1297         rc = io_subchannel_recog(cdev, sch);
1298         if (rc)
1299                 return rc;
1300
1301         /* Now wait for the async. recognition to come to an end. */
1302         spin_lock_irq(cdev->ccwlock);
1303         while (!dev_fsm_final_state(cdev))
1304                 wait_cons_dev();
1305         rc = -EIO;
1306         if (cdev->private->state != DEV_STATE_OFFLINE)
1307                 goto out_unlock;
1308         ccw_device_online(cdev);
1309         while (!dev_fsm_final_state(cdev))
1310                 wait_cons_dev();
1311         if (cdev->private->state != DEV_STATE_ONLINE)
1312                 goto out_unlock;
1313         rc = 0;
1314 out_unlock:
1315         spin_unlock_irq(cdev->ccwlock);
1316         return 0;
1317 }
1318
1319 struct ccw_device *
1320 ccw_device_probe_console(void)
1321 {
1322         struct subchannel *sch;
1323         int ret;
1324
1325         if (xchg(&console_cdev_in_use, 1) != 0)
1326                 return ERR_PTR(-EBUSY);
1327         sch = cio_probe_console();
1328         if (IS_ERR(sch)) {
1329                 console_cdev_in_use = 0;
1330                 return (void *) sch;
1331         }
1332         memset(&console_cdev, 0, sizeof(struct ccw_device));
1333         memset(&console_private, 0, sizeof(struct ccw_device_private));
1334         console_cdev.private = &console_private;
1335         console_private.cdev = &console_cdev;
1336         ret = ccw_device_console_enable(&console_cdev, sch);
1337         if (ret) {
1338                 cio_release_console();
1339                 console_cdev_in_use = 0;
1340                 return ERR_PTR(ret);
1341         }
1342         console_cdev.online = 1;
1343         return &console_cdev;
1344 }
1345 #endif
1346
1347 /*
1348  * get ccw_device matching the busid, but only if owned by cdrv
1349  */
1350 static int
1351 __ccwdev_check_busid(struct device *dev, void *id)
1352 {
1353         char *bus_id;
1354
1355         bus_id = id;
1356
1357         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1358 }
1359
1360
1361 /**
1362  * get_ccwdev_by_busid() - obtain device from a bus id
1363  * @cdrv: driver the device is owned by
1364  * @bus_id: bus id of the device to be searched
1365  *
1366  * This function searches all devices owned by @cdrv for a device with a bus
1367  * id matching @bus_id.
1368  * Returns:
1369  *  If a match is found, its reference count of the found device is increased
1370  *  and it is returned; else %NULL is returned.
1371  */
1372 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1373                                        const char *bus_id)
1374 {
1375         struct device *dev;
1376         struct device_driver *drv;
1377
1378         drv = get_driver(&cdrv->driver);
1379         if (!drv)
1380                 return NULL;
1381
1382         dev = driver_find_device(drv, NULL, (void *)bus_id,
1383                                  __ccwdev_check_busid);
1384         put_driver(drv);
1385
1386         return dev ? to_ccwdev(dev) : NULL;
1387 }
1388
1389 /************************** device driver handling ************************/
1390
1391 /* This is the implementation of the ccw_driver class. The probe, remove
1392  * and release methods are initially very similar to the device_driver
1393  * implementations, with the difference that they have ccw_device
1394  * arguments.
1395  *
1396  * A ccw driver also contains the information that is needed for
1397  * device matching.
1398  */
1399 static int
1400 ccw_device_probe (struct device *dev)
1401 {
1402         struct ccw_device *cdev = to_ccwdev(dev);
1403         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1404         int ret;
1405
1406         cdev->drv = cdrv; /* to let the driver call _set_online */
1407
1408         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1409
1410         if (ret) {
1411                 cdev->drv = NULL;
1412                 return ret;
1413         }
1414
1415         return 0;
1416 }
1417
1418 static int
1419 ccw_device_remove (struct device *dev)
1420 {
1421         struct ccw_device *cdev = to_ccwdev(dev);
1422         struct ccw_driver *cdrv = cdev->drv;
1423         int ret;
1424
1425         if (cdrv->remove)
1426                 cdrv->remove(cdev);
1427         if (cdev->online) {
1428                 cdev->online = 0;
1429                 spin_lock_irq(cdev->ccwlock);
1430                 ret = ccw_device_offline(cdev);
1431                 spin_unlock_irq(cdev->ccwlock);
1432                 if (ret == 0)
1433                         wait_event(cdev->private->wait_q,
1434                                    dev_fsm_final_state(cdev));
1435                 else
1436                         //FIXME: we can't fail!
1437                         CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1438                                       "device 0.%x.%04x\n",
1439                                       ret, cdev->private->dev_id.ssid,
1440                                       cdev->private->dev_id.devno);
1441         }
1442         ccw_device_set_timeout(cdev, 0);
1443         cdev->drv = NULL;
1444         return 0;
1445 }
1446
1447 static void ccw_device_shutdown(struct device *dev)
1448 {
1449         struct ccw_device *cdev;
1450
1451         cdev = to_ccwdev(dev);
1452         if (cdev->drv && cdev->drv->shutdown)
1453                 cdev->drv->shutdown(cdev);
1454         disable_cmf(cdev);
1455 }
1456
1457 struct bus_type ccw_bus_type = {
1458         .name   = "ccw",
1459         .match  = ccw_bus_match,
1460         .uevent = ccw_uevent,
1461         .probe  = ccw_device_probe,
1462         .remove = ccw_device_remove,
1463         .shutdown = ccw_device_shutdown,
1464 };
1465
1466 /**
1467  * ccw_driver_register() - register a ccw driver
1468  * @cdriver: driver to be registered
1469  *
1470  * This function is mainly a wrapper around driver_register().
1471  * Returns:
1472  *   %0 on success and a negative error value on failure.
1473  */
1474 int ccw_driver_register(struct ccw_driver *cdriver)
1475 {
1476         struct device_driver *drv = &cdriver->driver;
1477
1478         drv->bus = &ccw_bus_type;
1479         drv->name = cdriver->name;
1480         drv->owner = cdriver->owner;
1481
1482         return driver_register(drv);
1483 }
1484
1485 /**
1486  * ccw_driver_unregister() - deregister a ccw driver
1487  * @cdriver: driver to be deregistered
1488  *
1489  * This function is mainly a wrapper around driver_unregister().
1490  */
1491 void ccw_driver_unregister(struct ccw_driver *cdriver)
1492 {
1493         driver_unregister(&cdriver->driver);
1494 }
1495
1496 /* Helper func for qdio. */
1497 struct subchannel_id
1498 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1499 {
1500         struct subchannel *sch;
1501
1502         sch = to_subchannel(cdev->dev.parent);
1503         return sch->schid;
1504 }
1505
1506 MODULE_LICENSE("GPL");
1507 EXPORT_SYMBOL(ccw_device_set_online);
1508 EXPORT_SYMBOL(ccw_device_set_offline);
1509 EXPORT_SYMBOL(ccw_driver_register);
1510 EXPORT_SYMBOL(ccw_driver_unregister);
1511 EXPORT_SYMBOL(get_ccwdev_by_busid);
1512 EXPORT_SYMBOL(ccw_bus_type);
1513 EXPORT_SYMBOL(ccw_device_work);
1514 EXPORT_SYMBOL(ccw_device_notify_work);
1515 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);