git.oblomov.eu Git - linux-2.6/blob - drivers/s390/cio/device.c

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