drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *
   5  *    Copyright IBM Corp. 2002,2008
   6  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   8  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   9  */
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/errno.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/list.h>
  17 #include <linux/device.h>
  18 #include <linux/workqueue.h>
  19 #include <linux/timer.h>
  20
  21 #include <asm/ccwdev.h>
  22 #include <asm/cio.h>
  23 #include <asm/param.h>          /* HZ */
  24 #include <asm/cmb.h>
  25 #include <asm/isc.h>
  26
  27 #include "chp.h"
  28 #include "cio.h"
  29 #include "cio_debug.h"
  30 #include "css.h"
  31 #include "device.h"
  32 #include "ioasm.h"
  33 #include "io_sch.h"
  34 #include "blacklist.h"
  35
  36 static struct timer_list recovery_timer;
  37 static DEFINE_SPINLOCK(recovery_lock);
  38 static int recovery_phase;
  39 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  40
  41 /******************* bus type handling ***********************/
  42
  43 /* The Linux driver model distinguishes between a bus type and
  44  * the bus itself. Of course we only have one channel
  45  * subsystem driver and one channel system per machine, but
  46  * we still use the abstraction. T.R. says it's a good idea. */
  47 static int
  48 ccw_bus_match (struct device * dev, struct device_driver * drv)
  49 {
  50         struct ccw_device *cdev = to_ccwdev(dev);
  51         struct ccw_driver *cdrv = to_ccwdrv(drv);
  52         const struct ccw_device_id *ids = cdrv->ids, *found;
  53
  54         if (!ids)
  55                 return 0;
  56
  57         found = ccw_device_id_match(ids, &cdev->id);
  58         if (!found)
  59                 return 0;
  60
  61         cdev->id.driver_info = found->driver_info;
  62
  63         return 1;
  64 }
  65
  66 /* Store modalias string delimited by prefix/suffix string into buffer with
  67  * specified size. Return length of resulting string (excluding trailing '\0')
  68  * even if string doesn't fit buffer (snprintf semantics). */
  69 static int snprint_alias(char *buf, size_t size,
  70                          struct ccw_device_id *id, const char *suffix)
  71 {
  72         int len;
  73
  74         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  75         if (len > size)
  76                 return len;
  77         buf += len;
  78         size -= len;
  79
  80         if (id->dev_type != 0)
  81                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  82                                 id->dev_model, suffix);
  83         else
  84                 len += snprintf(buf, size, "dtdm%s", suffix);
  85
  86         return len;
  87 }
  88
  89 /* Set up environment variables for ccw device uevent. Return 0 on success,
  90  * non-zero otherwise. */
  91 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  92 {
  93         struct ccw_device *cdev = to_ccwdev(dev);
  94         struct ccw_device_id *id = &(cdev->id);
  95         int ret;
  96         char modalias_buf[30];
  97
  98         /* CU_TYPE= */
  99         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 100         if (ret)
 101                 return ret;
 102
 103         /* CU_MODEL= */
 104         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 105         if (ret)
 106                 return ret;
 107
 108         /* The next two can be zero, that's ok for us */
 109         /* DEV_TYPE= */
 110         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 111         if (ret)
 112                 return ret;
 113
 114         /* DEV_MODEL= */
 115         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 116         if (ret)
 117                 return ret;
 118
 119         /* MODALIAS=  */
 120         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 121         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 122         return ret;
 123 }
 124
 125 struct bus_type ccw_bus_type;
 126
 127 static void io_subchannel_irq(struct subchannel *);
 128 static int io_subchannel_probe(struct subchannel *);
 129 static int io_subchannel_remove(struct subchannel *);
 130 static void io_subchannel_shutdown(struct subchannel *);
 131 static int io_subchannel_sch_event(struct subchannel *, int);
 132 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 133                                    int);
 134
 135 static struct css_device_id io_subchannel_ids[] = {
 136         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 137         { /* end of list */ },
 138 };
 139 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 140
 141 static int io_subchannel_prepare(struct subchannel *sch)
 142 {
 143         struct ccw_device *cdev;
 144         /*
 145          * Don't allow suspend while a ccw device registration
 146          * is still outstanding.
 147          */
 148         cdev = sch_get_cdev(sch);
 149         if (cdev && !device_is_registered(&cdev->dev))
 150                 return -EAGAIN;
 151         return 0;
 152 }
 153
 154 static struct css_driver io_subchannel_driver = {
 155         .owner = THIS_MODULE,
 156         .subchannel_type = io_subchannel_ids,
 157         .name = "io_subchannel",
 158         .irq = io_subchannel_irq,
 159         .sch_event = io_subchannel_sch_event,
 160         .chp_event = io_subchannel_chp_event,
 161         .probe = io_subchannel_probe,
 162         .remove = io_subchannel_remove,
 163         .shutdown = io_subchannel_shutdown,
 164         .prepare = io_subchannel_prepare,
 165 };
 166
 167 struct workqueue_struct *ccw_device_work;
 168 wait_queue_head_t ccw_device_init_wq;
 169 atomic_t ccw_device_init_count;
 170
 171 static void recovery_func(unsigned long data);
 172
 173 static int __init
 174 init_ccw_bus_type (void)
 175 {
 176         int ret;
 177
 178         init_waitqueue_head(&ccw_device_init_wq);
 179         atomic_set(&ccw_device_init_count, 0);
 180         setup_timer(&recovery_timer, recovery_func, 0);
 181
 182         ccw_device_work = create_singlethread_workqueue("cio");
 183         if (!ccw_device_work)
 184                 return -ENOMEM; /* FIXME: better errno ? */
 185         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 186         if (!slow_path_wq) {
 187                 ret = -ENOMEM; /* FIXME: better errno ? */
 188                 goto out_err;
 189         }
 190         if ((ret = bus_register (&ccw_bus_type)))
 191                 goto out_err;
 192
 193         ret = css_driver_register(&io_subchannel_driver);
 194         if (ret)
 195                 goto out_err;
 196
 197         wait_event(ccw_device_init_wq,
 198                    atomic_read(&ccw_device_init_count) == 0);
 199         flush_workqueue(ccw_device_work);
 200         return 0;
 201 out_err:
 202         if (ccw_device_work)
 203                 destroy_workqueue(ccw_device_work);
 204         if (slow_path_wq)
 205                 destroy_workqueue(slow_path_wq);
 206         return ret;
 207 }
 208
 209 static void __exit
 210 cleanup_ccw_bus_type (void)
 211 {
 212         css_driver_unregister(&io_subchannel_driver);
 213         bus_unregister(&ccw_bus_type);
 214         destroy_workqueue(ccw_device_work);
 215 }
 216
 217 subsys_initcall(init_ccw_bus_type);
 218 module_exit(cleanup_ccw_bus_type);
 219
 220 /************************ device handling **************************/
 221
 222 /*
 223  * A ccw_device has some interfaces in sysfs in addition to the
 224  * standard ones.
 225  * The following entries are designed to export the information which
 226  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 227  * are obvious, so they don't have an entry :)
 228  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 229  */
 230 static ssize_t
 231 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 232 {
 233         struct subchannel *sch = to_subchannel(dev);
 234         struct chsc_ssd_info *ssd = &sch->ssd_info;
 235         ssize_t ret = 0;
 236         int chp;
 237         int mask;
 238
 239         for (chp = 0; chp < 8; chp++) {
 240                 mask = 0x80 >> chp;
 241                 if (ssd->path_mask & mask)
 242                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 243                 else
 244                         ret += sprintf(buf + ret, "00 ");
 245         }
 246         ret += sprintf (buf+ret, "\n");
 247         return min((ssize_t)PAGE_SIZE, ret);
 248 }
 249
 250 static ssize_t
 251 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 252 {
 253         struct subchannel *sch = to_subchannel(dev);
 254         struct pmcw *pmcw = &sch->schib.pmcw;
 255
 256         return sprintf (buf, "%02x %02x %02x\n",
 257                         pmcw->pim, pmcw->pam, pmcw->pom);
 258 }
 259
 260 static ssize_t
 261 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 262 {
 263         struct ccw_device *cdev = to_ccwdev(dev);
 264         struct ccw_device_id *id = &(cdev->id);
 265
 266         if (id->dev_type != 0)
 267                 return sprintf(buf, "%04x/%02x\n",
 268                                 id->dev_type, id->dev_model);
 269         else
 270                 return sprintf(buf, "n/a\n");
 271 }
 272
 273 static ssize_t
 274 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 275 {
 276         struct ccw_device *cdev = to_ccwdev(dev);
 277         struct ccw_device_id *id = &(cdev->id);
 278
 279         return sprintf(buf, "%04x/%02x\n",
 280                        id->cu_type, id->cu_model);
 281 }
 282
 283 static ssize_t
 284 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 285 {
 286         struct ccw_device *cdev = to_ccwdev(dev);
 287         struct ccw_device_id *id = &(cdev->id);
 288         int len;
 289
 290         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 291
 292         return len > PAGE_SIZE ? PAGE_SIZE : len;
 293 }
 294
 295 static ssize_t
 296 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 297 {
 298         struct ccw_device *cdev = to_ccwdev(dev);
 299
 300         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 301 }
 302
 303 int ccw_device_is_orphan(struct ccw_device *cdev)
 304 {
 305         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 306 }
 307
 308 static void ccw_device_unregister(struct ccw_device *cdev)
 309 {
 310         if (test_and_clear_bit(1, &cdev->private->registered))
 311                 device_del(&cdev->dev);
 312 }
 313
 314 static void ccw_device_remove_orphan_cb(struct work_struct *work)
 315 {
 316         struct ccw_device_private *priv;
 317         struct ccw_device *cdev;
 318
 319         priv = container_of(work, struct ccw_device_private, kick_work);
 320         cdev = priv->cdev;
 321         ccw_device_unregister(cdev);
 322         put_device(&cdev->dev);
 323         /* Release cdev reference for workqueue processing. */
 324         put_device(&cdev->dev);
 325 }
 326
 327 static void
 328 ccw_device_remove_disconnected(struct ccw_device *cdev)
 329 {
 330         unsigned long flags;
 331
 332         /*
 333          * Forced offline in disconnected state means
 334          * 'throw away device'.
 335          */
 336         if (ccw_device_is_orphan(cdev)) {
 337                 /*
 338                  * Deregister ccw device.
 339                  * Unfortunately, we cannot do this directly from the
 340                  * attribute method.
 341                  */
 342                 /* Get cdev reference for workqueue processing. */
 343                 if (!get_device(&cdev->dev))
 344                         return;
 345                 spin_lock_irqsave(cdev->ccwlock, flags);
 346                 cdev->private->state = DEV_STATE_NOT_OPER;
 347                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 348                 PREPARE_WORK(&cdev->private->kick_work,
 349                                 ccw_device_remove_orphan_cb);
 350                 queue_work(slow_path_wq, &cdev->private->kick_work);
 351         } else
 352                 /* Deregister subchannel, which will kill the ccw device. */
 353                 ccw_device_schedule_sch_unregister(cdev);
 354 }
 355
 356 /**
 357  * ccw_device_set_offline() - disable a ccw device for I/O
 358  * @cdev: target ccw device
 359  *
 360  * This function calls the driver's set_offline() function for @cdev, if
 361  * given, and then disables @cdev.
 362  * Returns:
 363  *   %0 on success and a negative error value on failure.
 364  * Context:
 365  *  enabled, ccw device lock not held
 366  */
 367 int ccw_device_set_offline(struct ccw_device *cdev)
 368 {
 369         int ret;
 370
 371         if (!cdev)
 372                 return -ENODEV;
 373         if (!cdev->online || !cdev->drv)
 374                 return -EINVAL;
 375
 376         if (cdev->drv->set_offline) {
 377                 ret = cdev->drv->set_offline(cdev);
 378                 if (ret != 0)
 379                         return ret;
 380         }
 381         cdev->online = 0;
 382         spin_lock_irq(cdev->ccwlock);
 383         ret = ccw_device_offline(cdev);
 384         if (ret == -ENODEV) {
 385                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 386                         cdev->private->state = DEV_STATE_OFFLINE;
 387                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 388                 }
 389                 spin_unlock_irq(cdev->ccwlock);
 390                 /* Give up reference from ccw_device_set_online(). */
 391                 put_device(&cdev->dev);
 392                 return ret;
 393         }
 394         spin_unlock_irq(cdev->ccwlock);
 395         if (ret == 0) {
 396                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 397                 /* Give up reference from ccw_device_set_online(). */
 398                 put_device(&cdev->dev);
 399         } else {
 400                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
 401                               "device 0.%x.%04x\n",
 402                               ret, cdev->private->dev_id.ssid,
 403                               cdev->private->dev_id.devno);
 404                 cdev->online = 1;
 405         }
 406         return ret;
 407 }
 408
 409 /**
 410  * ccw_device_set_online() - enable a ccw device for I/O
 411  * @cdev: target ccw device
 412  *
 413  * This function first enables @cdev and then calls the driver's set_online()
 414  * function for @cdev, if given. If set_online() returns an error, @cdev is
 415  * disabled again.
 416  * Returns:
 417  *   %0 on success and a negative error value on failure.
 418  * Context:
 419  *  enabled, ccw device lock not held
 420  */
 421 int ccw_device_set_online(struct ccw_device *cdev)
 422 {
 423         int ret;
 424
 425         if (!cdev)
 426                 return -ENODEV;
 427         if (cdev->online || !cdev->drv)
 428                 return -EINVAL;
 429         /* Hold on to an extra reference while device is online. */
 430         if (!get_device(&cdev->dev))
 431                 return -ENODEV;
 432
 433         spin_lock_irq(cdev->ccwlock);
 434         ret = ccw_device_online(cdev);
 435         spin_unlock_irq(cdev->ccwlock);
 436         if (ret == 0)
 437                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 438         else {
 439                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 440                               "device 0.%x.%04x\n",
 441                               ret, cdev->private->dev_id.ssid,
 442                               cdev->private->dev_id.devno);
 443                 /* Give up online reference since onlining failed. */
 444                 put_device(&cdev->dev);
 445                 return ret;
 446         }
 447         if (cdev->private->state != DEV_STATE_ONLINE) {
 448                 /* Give up online reference since onlining failed. */
 449                 put_device(&cdev->dev);
 450                 return -ENODEV;
 451         }
 452         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 453                 cdev->online = 1;
 454                 return 0;
 455         }
 456         spin_lock_irq(cdev->ccwlock);
 457         ret = ccw_device_offline(cdev);
 458         spin_unlock_irq(cdev->ccwlock);
 459         if (ret == 0)
 460                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 461         else
 462                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
 463                               "device 0.%x.%04x\n",
 464                               ret, cdev->private->dev_id.ssid,
 465                               cdev->private->dev_id.devno);
 466         /* Give up online reference since onlining failed. */
 467         put_device(&cdev->dev);
 468         return (ret == 0) ? -ENODEV : ret;
 469 }
 470
 471 static int online_store_handle_offline(struct ccw_device *cdev)
 472 {
 473         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 474                 ccw_device_remove_disconnected(cdev);
 475         else if (cdev->online && cdev->drv && cdev->drv->set_offline)
 476                 return ccw_device_set_offline(cdev);
 477         return 0;
 478 }
 479
 480 static int online_store_recog_and_online(struct ccw_device *cdev)
 481 {
 482         int ret;
 483
 484         /* Do device recognition, if needed. */
 485         if (cdev->private->state == DEV_STATE_BOXED) {
 486                 ret = ccw_device_recognition(cdev);
 487                 if (ret) {
 488                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 489                                       "for device 0.%x.%04x (ret=%d)\n",
 490                                       cdev->private->dev_id.ssid,
 491                                       cdev->private->dev_id.devno, ret);
 492                         return ret;
 493                 }
 494                 wait_event(cdev->private->wait_q,
 495                            cdev->private->flags.recog_done);
 496                 if (cdev->private->state != DEV_STATE_OFFLINE)
 497                         /* recognition failed */
 498                         return -EAGAIN;
 499         }
 500         if (cdev->drv && cdev->drv->set_online)
 501                 ccw_device_set_online(cdev);
 502         return 0;
 503 }
 504
 505 static int online_store_handle_online(struct ccw_device *cdev, int force)
 506 {
 507         int ret;
 508
 509         ret = online_store_recog_and_online(cdev);
 510         if (ret && !force)
 511                 return ret;
 512         if (force && cdev->private->state == DEV_STATE_BOXED) {
 513                 ret = ccw_device_stlck(cdev);
 514                 if (ret)
 515                         return ret;
 516                 if (cdev->id.cu_type == 0)
 517                         cdev->private->state = DEV_STATE_NOT_OPER;
 518                 ret = online_store_recog_and_online(cdev);
 519                 if (ret)
 520                         return ret;
 521         }
 522         return 0;
 523 }
 524
 525 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 526                              const char *buf, size_t count)
 527 {
 528         struct ccw_device *cdev = to_ccwdev(dev);
 529         int force, ret;
 530         unsigned long i;
 531
 532         if ((cdev->private->state != DEV_STATE_OFFLINE &&
 533              cdev->private->state != DEV_STATE_ONLINE &&
 534              cdev->private->state != DEV_STATE_BOXED &&
 535              cdev->private->state != DEV_STATE_DISCONNECTED) ||
 536             atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 537                 return -EAGAIN;
 538
 539         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 540                 atomic_set(&cdev->private->onoff, 0);
 541                 return -EINVAL;
 542         }
 543         if (!strncmp(buf, "force\n", count)) {
 544                 force = 1;
 545                 i = 1;
 546                 ret = 0;
 547         } else {
 548                 force = 0;
 549                 ret = strict_strtoul(buf, 16, &i);
 550         }
 551         if (ret)
 552                 goto out;
 553         switch (i) {
 554         case 0:
 555                 ret = online_store_handle_offline(cdev);
 556                 break;
 557         case 1:
 558                 ret = online_store_handle_online(cdev, force);
 559                 break;
 560         default:
 561                 ret = -EINVAL;
 562         }
 563 out:
 564         if (cdev->drv)
 565                 module_put(cdev->drv->owner);
 566         atomic_set(&cdev->private->onoff, 0);
 567         return (ret < 0) ? ret : count;
 568 }
 569
 570 static ssize_t
 571 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 572 {
 573         struct ccw_device *cdev = to_ccwdev(dev);
 574         struct subchannel *sch;
 575
 576         if (ccw_device_is_orphan(cdev))
 577                 return sprintf(buf, "no device\n");
 578         switch (cdev->private->state) {
 579         case DEV_STATE_BOXED:
 580                 return sprintf(buf, "boxed\n");
 581         case DEV_STATE_DISCONNECTED:
 582         case DEV_STATE_DISCONNECTED_SENSE_ID:
 583         case DEV_STATE_NOT_OPER:
 584                 sch = to_subchannel(dev->parent);
 585                 if (!sch->lpm)
 586                         return sprintf(buf, "no path\n");
 587                 else
 588                         return sprintf(buf, "no device\n");
 589         default:
 590                 /* All other states considered fine. */
 591                 return sprintf(buf, "good\n");
 592         }
 593 }
 594
 595 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 596 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 597 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 598 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 599 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 600 static DEVICE_ATTR(online, 0644, online_show, online_store);
 601 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 602
 603 static struct attribute *io_subchannel_attrs[] = {
 604         &dev_attr_chpids.attr,
 605         &dev_attr_pimpampom.attr,
 606         NULL,
 607 };
 608
 609 static struct attribute_group io_subchannel_attr_group = {
 610         .attrs = io_subchannel_attrs,
 611 };
 612
 613 static struct attribute * ccwdev_attrs[] = {
 614         &dev_attr_devtype.attr,
 615         &dev_attr_cutype.attr,
 616         &dev_attr_modalias.attr,
 617         &dev_attr_online.attr,
 618         &dev_attr_cmb_enable.attr,
 619         &dev_attr_availability.attr,
 620         NULL,
 621 };
 622
 623 static struct attribute_group ccwdev_attr_group = {
 624         .attrs = ccwdev_attrs,
 625 };
 626
 627 static struct attribute_group *ccwdev_attr_groups[] = {
 628         &ccwdev_attr_group,
 629         NULL,
 630 };
 631
 632 /* this is a simple abstraction for device_register that sets the
 633  * correct bus type and adds the bus specific files */
 634 static int ccw_device_register(struct ccw_device *cdev)
 635 {
 636         struct device *dev = &cdev->dev;
 637         int ret;
 638
 639         dev->bus = &ccw_bus_type;
 640
 641         if ((ret = device_add(dev)))
 642                 return ret;
 643
 644         set_bit(1, &cdev->private->registered);
 645         return ret;
 646 }
 647
 648 struct match_data {
 649         struct ccw_dev_id dev_id;
 650         struct ccw_device * sibling;
 651 };
 652
 653 static int
 654 match_devno(struct device * dev, void * data)
 655 {
 656         struct match_data * d = data;
 657         struct ccw_device * cdev;
 658
 659         cdev = to_ccwdev(dev);
 660         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 661             !ccw_device_is_orphan(cdev) &&
 662             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 663             (cdev != d->sibling))
 664                 return 1;
 665         return 0;
 666 }
 667
 668 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 669                                                      struct ccw_device *sibling)
 670 {
 671         struct device *dev;
 672         struct match_data data;
 673
 674         data.dev_id = *dev_id;
 675         data.sibling = sibling;
 676         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 677
 678         return dev ? to_ccwdev(dev) : NULL;
 679 }
 680
 681 static int match_orphan(struct device *dev, void *data)
 682 {
 683         struct ccw_dev_id *dev_id;
 684         struct ccw_device *cdev;
 685
 686         dev_id = data;
 687         cdev = to_ccwdev(dev);
 688         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 689 }
 690
 691 static struct ccw_device *
 692 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 693                               struct ccw_dev_id *dev_id)
 694 {
 695         struct device *dev;
 696
 697         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 698                                 match_orphan);
 699
 700         return dev ? to_ccwdev(dev) : NULL;
 701 }
 702
 703 void ccw_device_do_unbind_bind(struct work_struct *work)
 704 {
 705         struct ccw_device_private *priv;
 706         struct ccw_device *cdev;
 707         struct subchannel *sch;
 708         int ret;
 709
 710         priv = container_of(work, struct ccw_device_private, kick_work);
 711         cdev = priv->cdev;
 712         sch = to_subchannel(cdev->dev.parent);
 713
 714         if (test_bit(1, &cdev->private->registered)) {
 715                 device_release_driver(&cdev->dev);
 716                 ret = device_attach(&cdev->dev);
 717                 WARN_ON(ret == -ENODEV);
 718         }
 719 }
 720
 721 static void
 722 ccw_device_release(struct device *dev)
 723 {
 724         struct ccw_device *cdev;
 725
 726         cdev = to_ccwdev(dev);
 727         /* Release reference of parent subchannel. */
 728         put_device(cdev->dev.parent);
 729         kfree(cdev->private);
 730         kfree(cdev);
 731 }
 732
 733 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 734 {
 735         struct ccw_device *cdev;
 736
 737         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 738         if (cdev) {
 739                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 740                                         GFP_KERNEL | GFP_DMA);
 741                 if (cdev->private)
 742                         return cdev;
 743         }
 744         kfree(cdev);
 745         return ERR_PTR(-ENOMEM);
 746 }
 747
 748 static int io_subchannel_initialize_dev(struct subchannel *sch,
 749                                         struct ccw_device *cdev)
 750 {
 751         cdev->private->cdev = cdev;
 752         atomic_set(&cdev->private->onoff, 0);
 753         cdev->dev.parent = &sch->dev;
 754         cdev->dev.release = ccw_device_release;
 755         INIT_WORK(&cdev->private->kick_work, NULL);
 756         cdev->dev.groups = ccwdev_attr_groups;
 757         /* Do first half of device_register. */
 758         device_initialize(&cdev->dev);
 759         if (!get_device(&sch->dev)) {
 760                 /* Release reference from device_initialize(). */
 761                 put_device(&cdev->dev);
 762                 return -ENODEV;
 763         }
 764         return 0;
 765 }
 766
 767 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 768 {
 769         struct ccw_device *cdev;
 770         int ret;
 771
 772         cdev = io_subchannel_allocate_dev(sch);
 773         if (!IS_ERR(cdev)) {
 774                 ret = io_subchannel_initialize_dev(sch, cdev);
 775                 if (ret)
 776                         cdev = ERR_PTR(ret);
 777         }
 778         return cdev;
 779 }
 780
 781 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 782
 783 static void sch_attach_device(struct subchannel *sch,
 784                               struct ccw_device *cdev)
 785 {
 786         css_update_ssd_info(sch);
 787         spin_lock_irq(sch->lock);
 788         sch_set_cdev(sch, cdev);
 789         cdev->private->schid = sch->schid;
 790         cdev->ccwlock = sch->lock;
 791         ccw_device_trigger_reprobe(cdev);
 792         spin_unlock_irq(sch->lock);
 793 }
 794
 795 static void sch_attach_disconnected_device(struct subchannel *sch,
 796                                            struct ccw_device *cdev)
 797 {
 798         struct subchannel *other_sch;
 799         int ret;
 800
 801         /* Get reference for new parent. */
 802         if (!get_device(&sch->dev))
 803                 return;
 804         other_sch = to_subchannel(cdev->dev.parent);
 805         /* Note: device_move() changes cdev->dev.parent */
 806         ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 807         if (ret) {
 808                 CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
 809                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 810                               cdev->private->dev_id.devno, ret);
 811                 /* Put reference for new parent. */
 812                 put_device(&sch->dev);
 813                 return;
 814         }
 815         sch_set_cdev(other_sch, NULL);
 816         /* No need to keep a subchannel without ccw device around. */
 817         css_sch_device_unregister(other_sch);
 818         sch_attach_device(sch, cdev);
 819         /* Put reference for old parent. */
 820         put_device(&other_sch->dev);
 821 }
 822
 823 static void sch_attach_orphaned_device(struct subchannel *sch,
 824                                        struct ccw_device *cdev)
 825 {
 826         int ret;
 827         struct subchannel *pseudo_sch;
 828
 829         /* Get reference for new parent. */
 830         if (!get_device(&sch->dev))
 831                 return;
 832         pseudo_sch = to_subchannel(cdev->dev.parent);
 833         /*
 834          * Try to move the ccw device to its new subchannel.
 835          * Note: device_move() changes cdev->dev.parent
 836          */
 837         ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 838         if (ret) {
 839                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 840                               "failed (ret=%d)!\n",
 841                               cdev->private->dev_id.ssid,
 842                               cdev->private->dev_id.devno, ret);
 843                 /* Put reference for new parent. */
 844                 put_device(&sch->dev);
 845                 return;
 846         }
 847         sch_attach_device(sch, cdev);
 848         /* Put reference on pseudo subchannel. */
 849         put_device(&pseudo_sch->dev);
 850 }
 851
 852 static void sch_create_and_recog_new_device(struct subchannel *sch)
 853 {
 854         struct ccw_device *cdev;
 855
 856         /* Need to allocate a new ccw device. */
 857         cdev = io_subchannel_create_ccwdev(sch);
 858         if (IS_ERR(cdev)) {
 859                 /* OK, we did everything we could... */
 860                 css_sch_device_unregister(sch);
 861                 return;
 862         }
 863         spin_lock_irq(sch->lock);
 864         sch_set_cdev(sch, cdev);
 865         spin_unlock_irq(sch->lock);
 866         /* Start recognition for the new ccw device. */
 867         if (io_subchannel_recog(cdev, sch)) {
 868                 spin_lock_irq(sch->lock);
 869                 sch_set_cdev(sch, NULL);
 870                 spin_unlock_irq(sch->lock);
 871                 css_sch_device_unregister(sch);
 872                 /* Put reference from io_subchannel_create_ccwdev(). */
 873                 put_device(&sch->dev);
 874                 /* Give up initial reference. */
 875                 put_device(&cdev->dev);
 876         }
 877 }
 878
 879
 880 void ccw_device_move_to_orphanage(struct work_struct *work)
 881 {
 882         struct ccw_device_private *priv;
 883         struct ccw_device *cdev;
 884         struct ccw_device *replacing_cdev;
 885         struct subchannel *sch;
 886         int ret;
 887         struct channel_subsystem *css;
 888         struct ccw_dev_id dev_id;
 889
 890         priv = container_of(work, struct ccw_device_private, kick_work);
 891         cdev = priv->cdev;
 892         sch = to_subchannel(cdev->dev.parent);
 893         css = to_css(sch->dev.parent);
 894         dev_id.devno = sch->schib.pmcw.dev;
 895         dev_id.ssid = sch->schid.ssid;
 896
 897         /* Increase refcount for pseudo subchannel. */
 898         get_device(&css->pseudo_subchannel->dev);
 899         /*
 900          * Move the orphaned ccw device to the orphanage so the replacing
 901          * ccw device can take its place on the subchannel.
 902          * Note: device_move() changes cdev->dev.parent
 903          */
 904         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev,
 905                 DPM_ORDER_NONE);
 906         if (ret) {
 907                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 908                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 909                               cdev->private->dev_id.devno, ret);
 910                 /* Decrease refcount for pseudo subchannel again. */
 911                 put_device(&css->pseudo_subchannel->dev);
 912                 return;
 913         }
 914         cdev->ccwlock = css->pseudo_subchannel->lock;
 915         /*
 916          * Search for the replacing ccw device
 917          * - among the disconnected devices
 918          * - in the orphanage
 919          */
 920         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 921         if (replacing_cdev) {
 922                 sch_attach_disconnected_device(sch, replacing_cdev);
 923                 /* Release reference from get_disc_ccwdev_by_dev_id() */
 924                 put_device(&replacing_cdev->dev);
 925                 /* Release reference of subchannel from old cdev. */
 926                 put_device(&sch->dev);
 927                 return;
 928         }
 929         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 930         if (replacing_cdev) {
 931                 sch_attach_orphaned_device(sch, replacing_cdev);
 932                 /* Release reference from get_orphaned_ccwdev_by_dev_id() */
 933                 put_device(&replacing_cdev->dev);
 934                 /* Release reference of subchannel from old cdev. */
 935                 put_device(&sch->dev);
 936                 return;
 937         }
 938         sch_create_and_recog_new_device(sch);
 939         /* Release reference of subchannel from old cdev. */
 940         put_device(&sch->dev);
 941 }
 942
 943 /*
 944  * Register recognized device.
 945  */
 946 static void
 947 io_subchannel_register(struct work_struct *work)
 948 {
 949         struct ccw_device_private *priv;
 950         struct ccw_device *cdev;
 951         struct subchannel *sch;
 952         int ret;
 953         unsigned long flags;
 954
 955         priv = container_of(work, struct ccw_device_private, kick_work);
 956         cdev = priv->cdev;
 957         sch = to_subchannel(cdev->dev.parent);
 958         /*
 959          * Check if subchannel is still registered. It may have become
 960          * unregistered if a machine check hit us after finishing
 961          * device recognition but before the register work could be
 962          * queued.
 963          */
 964         if (!device_is_registered(&sch->dev))
 965                 goto out_err;
 966         css_update_ssd_info(sch);
 967         /*
 968          * io_subchannel_register() will also be called after device
 969          * recognition has been done for a boxed device (which will already
 970          * be registered). We need to reprobe since we may now have sense id
 971          * information.
 972          */
 973         if (device_is_registered(&cdev->dev)) {
 974                 if (!cdev->drv) {
 975                         ret = device_reprobe(&cdev->dev);
 976                         if (ret)
 977                                 /* We can't do much here. */
 978                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 979                                               " %d for 0.%x.%04x\n", ret,
 980                                               cdev->private->dev_id.ssid,
 981                                               cdev->private->dev_id.devno);
 982                 }
 983                 goto out;
 984         }
 985         /*
 986          * Now we know this subchannel will stay, we can throw
 987          * our delayed uevent.
 988          */
 989         dev_set_uevent_suppress(&sch->dev, 0);
 990         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 991         /* make it known to the system */
 992         ret = ccw_device_register(cdev);
 993         if (ret) {
 994                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 995                               cdev->private->dev_id.ssid,
 996                               cdev->private->dev_id.devno, ret);
 997                 spin_lock_irqsave(sch->lock, flags);
 998                 sch_set_cdev(sch, NULL);
 999                 spin_unlock_irqrestore(sch->lock, flags);
1000                 /* Release initial device reference. */
1001                 put_device(&cdev->dev);
1002                 goto out_err;
1003         }
1004 out:
1005         cdev->private->flags.recog_done = 1;
1006         wake_up(&cdev->private->wait_q);
1007 out_err:
1008         /* Release reference for workqueue processing. */
1009         put_device(&cdev->dev);
1010         if (atomic_dec_and_test(&ccw_device_init_count))
1011                 wake_up(&ccw_device_init_wq);
1012 }
1013
1014 static void ccw_device_call_sch_unregister(struct work_struct *work)
1015 {
1016         struct ccw_device_private *priv;
1017         struct ccw_device *cdev;
1018         struct subchannel *sch;
1019
1020         priv = container_of(work, struct ccw_device_private, kick_work);
1021         cdev = priv->cdev;
1022         /* Get subchannel reference for local processing. */
1023         if (!get_device(cdev->dev.parent))
1024                 return;
1025         sch = to_subchannel(cdev->dev.parent);
1026         css_sch_device_unregister(sch);
1027         /* Release cdev reference for workqueue processing.*/
1028         put_device(&cdev->dev);
1029         /* Release subchannel reference for local processing. */
1030         put_device(&sch->dev);
1031 }
1032
1033 void ccw_device_schedule_sch_unregister(struct ccw_device *cdev)
1034 {
1035         /* Get cdev reference for workqueue processing. */
1036         if (!get_device(&cdev->dev))
1037                 return;
1038         PREPARE_WORK(&cdev->private->kick_work,
1039                      ccw_device_call_sch_unregister);
1040         queue_work(slow_path_wq, &cdev->private->kick_work);
1041 }
1042
1043 /*
1044  * subchannel recognition done. Called from the state machine.
1045  */
1046 void
1047 io_subchannel_recog_done(struct ccw_device *cdev)
1048 {
1049         if (css_init_done == 0) {
1050                 cdev->private->flags.recog_done = 1;
1051                 return;
1052         }
1053         switch (cdev->private->state) {
1054         case DEV_STATE_BOXED:
1055                 /* Device did not respond in time. */
1056         case DEV_STATE_NOT_OPER:
1057                 cdev->private->flags.recog_done = 1;
1058                 ccw_device_schedule_sch_unregister(cdev);
1059                 if (atomic_dec_and_test(&ccw_device_init_count))
1060                         wake_up(&ccw_device_init_wq);
1061                 break;
1062         case DEV_STATE_OFFLINE:
1063                 /*
1064                  * We can't register the device in interrupt context so
1065                  * we schedule a work item.
1066                  */
1067                 if (!get_device(&cdev->dev))
1068                         break;
1069                 PREPARE_WORK(&cdev->private->kick_work,
1070                              io_subchannel_register);
1071                 queue_work(slow_path_wq, &cdev->private->kick_work);
1072                 break;
1073         }
1074 }
1075
1076 static int
1077 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1078 {
1079         int rc;
1080         struct ccw_device_private *priv;
1081
1082         sch_set_cdev(sch, cdev);
1083         cdev->ccwlock = sch->lock;
1084
1085         /* Init private data. */
1086         priv = cdev->private;
1087         priv->dev_id.devno = sch->schib.pmcw.dev;
1088         priv->dev_id.ssid = sch->schid.ssid;
1089         priv->schid = sch->schid;
1090         priv->state = DEV_STATE_NOT_OPER;
1091         INIT_LIST_HEAD(&priv->cmb_list);
1092         init_waitqueue_head(&priv->wait_q);
1093         init_timer(&priv->timer);
1094
1095         /* Set an initial name for the device. */
1096         if (cio_is_console(sch->schid))
1097                 cdev->dev.init_name = cio_get_console_cdev_name(sch);
1098         else
1099                 dev_set_name(&cdev->dev, "0.%x.%04x",
1100                              sch->schid.ssid, sch->schib.pmcw.dev);
1101
1102         /* Increase counter of devices currently in recognition. */
1103         atomic_inc(&ccw_device_init_count);
1104
1105         /* Start async. device sensing. */
1106         spin_lock_irq(sch->lock);
1107         rc = ccw_device_recognition(cdev);
1108         spin_unlock_irq(sch->lock);
1109         if (rc) {
1110                 if (atomic_dec_and_test(&ccw_device_init_count))
1111                         wake_up(&ccw_device_init_wq);
1112         }
1113         return rc;
1114 }
1115
1116 static void ccw_device_move_to_sch(struct work_struct *work)
1117 {
1118         struct ccw_device_private *priv;
1119         int rc;
1120         struct subchannel *sch;
1121         struct ccw_device *cdev;
1122         struct subchannel *former_parent;
1123
1124         priv = container_of(work, struct ccw_device_private, kick_work);
1125         sch = priv->sch;
1126         cdev = priv->cdev;
1127         former_parent = to_subchannel(cdev->dev.parent);
1128         /* Get reference for new parent. */
1129         if (!get_device(&sch->dev))
1130                 return;
1131         mutex_lock(&sch->reg_mutex);
1132         /*
1133          * Try to move the ccw device to its new subchannel.
1134          * Note: device_move() changes cdev->dev.parent
1135          */
1136         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
1137         mutex_unlock(&sch->reg_mutex);
1138         if (rc) {
1139                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
1140                               "0.%x.%04x failed (ret=%d)!\n",
1141                               cdev->private->dev_id.ssid,
1142                               cdev->private->dev_id.devno, sch->schid.ssid,
1143                               sch->schid.sch_no, rc);
1144                 css_sch_device_unregister(sch);
1145                 /* Put reference for new parent again. */
1146                 put_device(&sch->dev);
1147                 goto out;
1148         }
1149         if (!sch_is_pseudo_sch(former_parent)) {
1150                 spin_lock_irq(former_parent->lock);
1151                 sch_set_cdev(former_parent, NULL);
1152                 spin_unlock_irq(former_parent->lock);
1153                 css_sch_device_unregister(former_parent);
1154                 /* Reset intparm to zeroes. */
1155                 former_parent->config.intparm = 0;
1156                 cio_commit_config(former_parent);
1157         }
1158         sch_attach_device(sch, cdev);
1159 out:
1160         /* Put reference for old parent. */
1161         put_device(&former_parent->dev);
1162         put_device(&cdev->dev);
1163 }
1164
1165 static void io_subchannel_irq(struct subchannel *sch)
1166 {
1167         struct ccw_device *cdev;
1168
1169         cdev = sch_get_cdev(sch);
1170
1171         CIO_TRACE_EVENT(6, "IRQ");
1172         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1173         if (cdev)
1174                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1175 }
1176
1177 void io_subchannel_init_config(struct subchannel *sch)
1178 {
1179         memset(&sch->config, 0, sizeof(sch->config));
1180         sch->config.csense = 1;
1181         /* Use subchannel mp mode when there is more than 1 installed CHPID. */
1182         if ((sch->schib.pmcw.pim & (sch->schib.pmcw.pim - 1)) != 0)
1183                 sch->config.mp = 1;
1184 }
1185
1186 static void io_subchannel_init_fields(struct subchannel *sch)
1187 {
1188         if (cio_is_console(sch->schid))
1189                 sch->opm = 0xff;
1190         else
1191                 sch->opm = chp_get_sch_opm(sch);
1192         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1193         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1194
1195         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1196                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1197                       sch->schib.pmcw.dev, sch->schid.ssid,
1198                       sch->schid.sch_no, sch->schib.pmcw.pim,
1199                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1200
1201         io_subchannel_init_config(sch);
1202 }
1203
1204 static void io_subchannel_do_unreg(struct work_struct *work)
1205 {
1206         struct subchannel *sch;
1207
1208         sch = container_of(work, struct subchannel, work);
1209         css_sch_device_unregister(sch);
1210         put_device(&sch->dev);
1211 }
1212
1213 /* Schedule unregister if we have no cdev. */
1214 static void io_subchannel_schedule_removal(struct subchannel *sch)
1215 {
1216         get_device(&sch->dev);
1217         INIT_WORK(&sch->work, io_subchannel_do_unreg);
1218         queue_work(slow_path_wq, &sch->work);
1219 }
1220
1221 /*
1222  * Note: We always return 0 so that we bind to the device even on error.
1223  * This is needed so that our remove function is called on unregister.
1224  */
1225 static int io_subchannel_probe(struct subchannel *sch)
1226 {
1227         struct ccw_device *cdev;
1228         int rc;
1229         unsigned long flags;
1230         struct ccw_dev_id dev_id;
1231
1232         cdev = sch_get_cdev(sch);
1233         if (cdev) {
1234                 rc = sysfs_create_group(&sch->dev.kobj,
1235                                         &io_subchannel_attr_group);
1236                 if (rc)
1237                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1238                                       "attributes for subchannel "
1239                                       "0.%x.%04x (rc=%d)\n",
1240                                       sch->schid.ssid, sch->schid.sch_no, rc);
1241                 /*
1242                  * This subchannel already has an associated ccw_device.
1243                  * Throw the delayed uevent for the subchannel, register
1244                  * the ccw_device and exit. This happens for all early
1245                  * devices, e.g. the console.
1246                  */
1247                 dev_set_uevent_suppress(&sch->dev, 0);
1248                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1249                 cdev->dev.groups = ccwdev_attr_groups;
1250                 device_initialize(&cdev->dev);
1251                 ccw_device_register(cdev);
1252                 /*
1253                  * Check if the device is already online. If it is
1254                  * the reference count needs to be corrected since we
1255                  * didn't obtain a reference in ccw_device_set_online.
1256                  */
1257                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1258                     cdev->private->state != DEV_STATE_OFFLINE &&
1259                     cdev->private->state != DEV_STATE_BOXED)
1260                         get_device(&cdev->dev);
1261                 return 0;
1262         }
1263         io_subchannel_init_fields(sch);
1264         rc = cio_commit_config(sch);
1265         if (rc)
1266                 goto out_schedule;
1267         rc = sysfs_create_group(&sch->dev.kobj,
1268                                 &io_subchannel_attr_group);
1269         if (rc)
1270                 goto out_schedule;
1271         /* Allocate I/O subchannel private data. */
1272         sch->private = kzalloc(sizeof(struct io_subchannel_private),
1273                                GFP_KERNEL | GFP_DMA);
1274         if (!sch->private)
1275                 goto out_err;
1276         /*
1277          * First check if a fitting device may be found amongst the
1278          * disconnected devices or in the orphanage.
1279          */
1280         dev_id.devno = sch->schib.pmcw.dev;
1281         dev_id.ssid = sch->schid.ssid;
1282         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1283         if (!cdev)
1284                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1285                                                      &dev_id);
1286         if (cdev) {
1287                 /*
1288                  * Schedule moving the device until when we have a registered
1289                  * subchannel to move to and succeed the probe. We can
1290                  * unregister later again, when the probe is through.
1291                  */
1292                 cdev->private->sch = sch;
1293                 PREPARE_WORK(&cdev->private->kick_work,
1294                              ccw_device_move_to_sch);
1295                 queue_work(slow_path_wq, &cdev->private->kick_work);
1296                 return 0;
1297         }
1298         cdev = io_subchannel_create_ccwdev(sch);
1299         if (IS_ERR(cdev))
1300                 goto out_err;
1301         rc = io_subchannel_recog(cdev, sch);
1302         if (rc) {
1303                 spin_lock_irqsave(sch->lock, flags);
1304                 io_subchannel_recog_done(cdev);
1305                 spin_unlock_irqrestore(sch->lock, flags);
1306         }
1307         return 0;
1308 out_err:
1309         kfree(sch->private);
1310         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1311 out_schedule:
1312         io_subchannel_schedule_removal(sch);
1313         return 0;
1314 }
1315
1316 static int
1317 io_subchannel_remove (struct subchannel *sch)
1318 {
1319         struct ccw_device *cdev;
1320         unsigned long flags;
1321
1322         cdev = sch_get_cdev(sch);
1323         if (!cdev)
1324                 return 0;
1325         /* Set ccw device to not operational and drop reference. */
1326         spin_lock_irqsave(cdev->ccwlock, flags);
1327         sch_set_cdev(sch, NULL);
1328         cdev->private->state = DEV_STATE_NOT_OPER;
1329         spin_unlock_irqrestore(cdev->ccwlock, flags);
1330         ccw_device_unregister(cdev);
1331         put_device(&cdev->dev);
1332         kfree(sch->private);
1333         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1334         return 0;
1335 }
1336
1337 static int io_subchannel_notify(struct subchannel *sch, int event)
1338 {
1339         struct ccw_device *cdev;
1340
1341         cdev = sch_get_cdev(sch);
1342         if (!cdev)
1343                 return 0;
1344         return ccw_device_notify(cdev, event);
1345 }
1346
1347 static void io_subchannel_verify(struct subchannel *sch)
1348 {
1349         struct ccw_device *cdev;
1350
1351         cdev = sch_get_cdev(sch);
1352         if (cdev)
1353                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1354 }
1355
1356 static int check_for_io_on_path(struct subchannel *sch, int mask)
1357 {
1358         if (cio_update_schib(sch))
1359                 return 0;
1360         if (scsw_actl(&sch->schib.scsw) && sch->schib.pmcw.lpum == mask)
1361                 return 1;
1362         return 0;
1363 }
1364
1365 static void terminate_internal_io(struct subchannel *sch,
1366                                   struct ccw_device *cdev)
1367 {
1368         if (cio_clear(sch)) {
1369                 /* Recheck device in case clear failed. */
1370                 sch->lpm = 0;
1371                 if (cdev->online)
1372                         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1373                 else
1374                         css_schedule_eval(sch->schid);
1375                 return;
1376         }
1377         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1378         /* Request retry of internal operation. */
1379         cdev->private->flags.intretry = 1;
1380         /* Call handler. */
1381         if (cdev->handler)
1382                 cdev->handler(cdev, cdev->private->intparm,
1383                               ERR_PTR(-EIO));
1384 }
1385
1386 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1387 {
1388         struct ccw_device *cdev;
1389
1390         cdev = sch_get_cdev(sch);
1391         if (!cdev)
1392                 return;
1393         if (check_for_io_on_path(sch, mask)) {
1394                 if (cdev->private->state == DEV_STATE_ONLINE)
1395                         ccw_device_kill_io(cdev);
1396                 else {
1397                         terminate_internal_io(sch, cdev);
1398                         /* Re-start path verification. */
1399                         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1400                 }
1401         } else
1402                 /* trigger path verification. */
1403                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1404
1405 }
1406
1407 static int io_subchannel_chp_event(struct subchannel *sch,
1408                                    struct chp_link *link, int event)
1409 {
1410         int mask;
1411
1412         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1413         if (!mask)
1414                 return 0;
1415         switch (event) {
1416         case CHP_VARY_OFF:
1417                 sch->opm &= ~mask;
1418                 sch->lpm &= ~mask;
1419                 io_subchannel_terminate_path(sch, mask);
1420                 break;
1421         case CHP_VARY_ON:
1422                 sch->opm |= mask;
1423                 sch->lpm |= mask;
1424                 io_subchannel_verify(sch);
1425                 break;
1426         case CHP_OFFLINE:
1427                 if (cio_update_schib(sch))
1428                         return -ENODEV;
1429                 io_subchannel_terminate_path(sch, mask);
1430                 break;
1431         case CHP_ONLINE:
1432                 if (cio_update_schib(sch))
1433                         return -ENODEV;
1434                 sch->lpm |= mask & sch->opm;
1435                 io_subchannel_verify(sch);
1436                 break;
1437         }
1438         return 0;
1439 }
1440
1441 static void
1442 io_subchannel_shutdown(struct subchannel *sch)
1443 {
1444         struct ccw_device *cdev;
1445         int ret;
1446
1447         cdev = sch_get_cdev(sch);
1448
1449         if (cio_is_console(sch->schid))
1450                 return;
1451         if (!sch->schib.pmcw.ena)
1452                 /* Nothing to do. */
1453                 return;
1454         ret = cio_disable_subchannel(sch);
1455         if (ret != -EBUSY)
1456                 /* Subchannel is disabled, we're done. */
1457                 return;
1458         cdev->private->state = DEV_STATE_QUIESCE;
1459         if (cdev->handler)
1460                 cdev->handler(cdev, cdev->private->intparm,
1461                               ERR_PTR(-EIO));
1462         ret = ccw_device_cancel_halt_clear(cdev);
1463         if (ret == -EBUSY) {
1464                 ccw_device_set_timeout(cdev, HZ/10);
1465                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1466         }
1467         cio_disable_subchannel(sch);
1468 }
1469
1470 static int io_subchannel_get_status(struct subchannel *sch)
1471 {
1472         struct schib schib;
1473
1474         if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
1475                 return CIO_GONE;
1476         if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
1477                 return CIO_REVALIDATE;
1478         if (!sch->lpm)
1479                 return CIO_NO_PATH;
1480         return CIO_OPER;
1481 }
1482
1483 static int device_is_disconnected(struct ccw_device *cdev)
1484 {
1485         if (!cdev)
1486                 return 0;
1487         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1488                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1489 }
1490
1491 static int recovery_check(struct device *dev, void *data)
1492 {
1493         struct ccw_device *cdev = to_ccwdev(dev);
1494         int *redo = data;
1495
1496         spin_lock_irq(cdev->ccwlock);
1497         switch (cdev->private->state) {
1498         case DEV_STATE_DISCONNECTED:
1499                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1500                               cdev->private->dev_id.ssid,
1501                               cdev->private->dev_id.devno);
1502                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1503                 *redo = 1;
1504                 break;
1505         case DEV_STATE_DISCONNECTED_SENSE_ID:
1506                 *redo = 1;
1507                 break;
1508         }
1509         spin_unlock_irq(cdev->ccwlock);
1510
1511         return 0;
1512 }
1513
1514 static void recovery_work_func(struct work_struct *unused)
1515 {
1516         int redo = 0;
1517
1518         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1519         if (redo) {
1520                 spin_lock_irq(&recovery_lock);
1521                 if (!timer_pending(&recovery_timer)) {
1522                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1523                                 recovery_phase++;
1524                         mod_timer(&recovery_timer, jiffies +
1525                                   recovery_delay[recovery_phase] * HZ);
1526                 }
1527                 spin_unlock_irq(&recovery_lock);
1528         } else
1529                 CIO_MSG_EVENT(4, "recovery: end\n");
1530 }
1531
1532 static DECLARE_WORK(recovery_work, recovery_work_func);
1533
1534 static void recovery_func(unsigned long data)
1535 {
1536         /*
1537          * We can't do our recovery in softirq context and it's not
1538          * performance critical, so we schedule it.
1539          */
1540         schedule_work(&recovery_work);
1541 }
1542
1543 static void ccw_device_schedule_recovery(void)
1544 {
1545         unsigned long flags;
1546
1547         CIO_MSG_EVENT(4, "recovery: schedule\n");
1548         spin_lock_irqsave(&recovery_lock, flags);
1549         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1550                 recovery_phase = 0;
1551                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1552         }
1553         spin_unlock_irqrestore(&recovery_lock, flags);
1554 }
1555
1556 static int purge_fn(struct device *dev, void *data)
1557 {
1558         struct ccw_device *cdev = to_ccwdev(dev);
1559         struct ccw_device_private *priv = cdev->private;
1560         int unreg;
1561
1562         spin_lock_irq(cdev->ccwlock);
1563         unreg = is_blacklisted(priv->dev_id.ssid, priv->dev_id.devno) &&
1564                 (priv->state == DEV_STATE_OFFLINE);
1565         spin_unlock_irq(cdev->ccwlock);
1566         if (!unreg)
1567                 goto out;
1568         CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", priv->dev_id.ssid,
1569                       priv->dev_id.devno);
1570         ccw_device_schedule_sch_unregister(cdev);
1571
1572 out:
1573         /* Abort loop in case of pending signal. */
1574         if (signal_pending(current))
1575                 return -EINTR;
1576
1577         return 0;
1578 }
1579
1580 /**
1581  * ccw_purge_blacklisted - purge unused, blacklisted devices
1582  *
1583  * Unregister all ccw devices that are offline and on the blacklist.
1584  */
1585 int ccw_purge_blacklisted(void)
1586 {
1587         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1588         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1589         return 0;
1590 }
1591
1592 static void device_set_disconnected(struct ccw_device *cdev)
1593 {
1594         if (!cdev)
1595                 return;
1596         ccw_device_set_timeout(cdev, 0);
1597         cdev->private->flags.fake_irb = 0;
1598         cdev->private->state = DEV_STATE_DISCONNECTED;
1599         if (cdev->online)
1600                 ccw_device_schedule_recovery();
1601 }
1602
1603 void ccw_device_set_notoper(struct ccw_device *cdev)
1604 {
1605         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1606
1607         CIO_TRACE_EVENT(2, "notoper");
1608         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1609         ccw_device_set_timeout(cdev, 0);
1610         cio_disable_subchannel(sch);
1611         cdev->private->state = DEV_STATE_NOT_OPER;
1612 }
1613
1614 static int io_subchannel_sch_event(struct subchannel *sch, int slow)
1615 {
1616         int event, ret, disc;
1617         unsigned long flags;
1618         enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE, DISC } action;
1619         struct ccw_device *cdev;
1620
1621         spin_lock_irqsave(sch->lock, flags);
1622         cdev = sch_get_cdev(sch);
1623         disc = device_is_disconnected(cdev);
1624         if (disc && slow) {
1625                 /* Disconnected devices are evaluated directly only.*/
1626                 spin_unlock_irqrestore(sch->lock, flags);
1627                 return 0;
1628         }
1629         /* No interrupt after machine check - kill pending timers. */
1630         if (cdev)
1631                 ccw_device_set_timeout(cdev, 0);
1632         if (!disc && !slow) {
1633                 /* Non-disconnected devices are evaluated on the slow path. */
1634                 spin_unlock_irqrestore(sch->lock, flags);
1635                 return -EAGAIN;
1636         }
1637         event = io_subchannel_get_status(sch);
1638         CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
1639                       sch->schid.ssid, sch->schid.sch_no, event,
1640                       disc ? "disconnected" : "normal",
1641                       slow ? "slow" : "fast");
1642         /* Analyze subchannel status. */
1643         action = NONE;
1644         switch (event) {
1645         case CIO_NO_PATH:
1646                 if (disc) {
1647                         /* Check if paths have become available. */
1648                         action = REPROBE;
1649                         break;
1650                 }
1651                 /* fall through */
1652         case CIO_GONE:
1653                 /* Ask driver what to do with device. */
1654                 if (io_subchannel_notify(sch, event))
1655                         action = DISC;
1656                 else
1657                         action = UNREGISTER;
1658                 break;
1659         case CIO_REVALIDATE:
1660                 /* Device will be removed, so no notify necessary. */
1661                 if (disc)
1662                         /* Reprobe because immediate unregister might block. */
1663                         action = REPROBE;
1664                 else
1665                         action = UNREGISTER_PROBE;
1666                 break;
1667         case CIO_OPER:
1668                 if (disc)
1669                         /* Get device operational again. */
1670                         action = REPROBE;
1671                 break;
1672         }
1673         /* Perform action. */
1674         ret = 0;
1675         switch (action) {
1676         case UNREGISTER:
1677         case UNREGISTER_PROBE:
1678                 ccw_device_set_notoper(cdev);
1679                 /* Unregister device (will use subchannel lock). */
1680                 spin_unlock_irqrestore(sch->lock, flags);
1681                 css_sch_device_unregister(sch);
1682                 spin_lock_irqsave(sch->lock, flags);
1683                 break;
1684         case REPROBE:
1685                 ccw_device_trigger_reprobe(cdev);
1686                 break;
1687         case DISC:
1688                 device_set_disconnected(cdev);
1689                 break;
1690         default:
1691                 break;
1692         }
1693         spin_unlock_irqrestore(sch->lock, flags);
1694         /* Probe if necessary. */
1695         if (action == UNREGISTER_PROBE)
1696                 ret = css_probe_device(sch->schid);
1697
1698         return ret;
1699 }
1700
1701 #ifdef CONFIG_CCW_CONSOLE
1702 static struct ccw_device console_cdev;
1703 static char console_cdev_name[10] = "0.x.xxxx";
1704 static struct ccw_device_private console_private;
1705 static int console_cdev_in_use;
1706
1707 static DEFINE_SPINLOCK(ccw_console_lock);
1708
1709 spinlock_t * cio_get_console_lock(void)
1710 {
1711         return &ccw_console_lock;
1712 }
1713
1714 static int ccw_device_console_enable(struct ccw_device *cdev,
1715                                      struct subchannel *sch)
1716 {
1717         int rc;
1718
1719         /* Attach subchannel private data. */
1720         sch->private = cio_get_console_priv();
1721         memset(sch->private, 0, sizeof(struct io_subchannel_private));
1722         io_subchannel_init_fields(sch);
1723         rc = cio_commit_config(sch);
1724         if (rc)
1725                 return rc;
1726         sch->driver = &io_subchannel_driver;
1727         /* Initialize the ccw_device structure. */
1728         cdev->dev.parent= &sch->dev;
1729         rc = io_subchannel_recog(cdev, sch);
1730         if (rc)
1731                 return rc;
1732
1733         /* Now wait for the async. recognition to come to an end. */
1734         spin_lock_irq(cdev->ccwlock);
1735         while (!dev_fsm_final_state(cdev))
1736                 wait_cons_dev();
1737         rc = -EIO;
1738         if (cdev->private->state != DEV_STATE_OFFLINE)
1739                 goto out_unlock;
1740         ccw_device_online(cdev);
1741         while (!dev_fsm_final_state(cdev))
1742                 wait_cons_dev();
1743         if (cdev->private->state != DEV_STATE_ONLINE)
1744                 goto out_unlock;
1745         rc = 0;
1746 out_unlock:
1747         spin_unlock_irq(cdev->ccwlock);
1748         return 0;
1749 }
1750
1751 struct ccw_device *
1752 ccw_device_probe_console(void)
1753 {
1754         struct subchannel *sch;
1755         int ret;
1756
1757         if (xchg(&console_cdev_in_use, 1) != 0)
1758                 return ERR_PTR(-EBUSY);
1759         sch = cio_probe_console();
1760         if (IS_ERR(sch)) {
1761                 console_cdev_in_use = 0;
1762                 return (void *) sch;
1763         }
1764         memset(&console_cdev, 0, sizeof(struct ccw_device));
1765         memset(&console_private, 0, sizeof(struct ccw_device_private));
1766         console_cdev.private = &console_private;
1767         console_private.cdev = &console_cdev;
1768         ret = ccw_device_console_enable(&console_cdev, sch);
1769         if (ret) {
1770                 cio_release_console();
1771                 console_cdev_in_use = 0;
1772                 return ERR_PTR(ret);
1773         }
1774         console_cdev.online = 1;
1775         return &console_cdev;
1776 }
1777
1778 static int ccw_device_pm_restore(struct device *dev);
1779
1780 int ccw_device_force_console(void)
1781 {
1782         if (!console_cdev_in_use)
1783                 return -ENODEV;
1784         return ccw_device_pm_restore(&console_cdev.dev);
1785 }
1786 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1787
1788 const char *cio_get_console_cdev_name(struct subchannel *sch)
1789 {
1790         snprintf(console_cdev_name, 10, "0.%x.%04x",
1791                  sch->schid.ssid, sch->schib.pmcw.dev);
1792         return (const char *)console_cdev_name;
1793 }
1794 #endif
1795
1796 /*
1797  * get ccw_device matching the busid, but only if owned by cdrv
1798  */
1799 static int
1800 __ccwdev_check_busid(struct device *dev, void *id)
1801 {
1802         char *bus_id;
1803
1804         bus_id = id;
1805
1806         return (strcmp(bus_id, dev_name(dev)) == 0);
1807 }
1808
1809
1810 /**
1811  * get_ccwdev_by_busid() - obtain device from a bus id
1812  * @cdrv: driver the device is owned by
1813  * @bus_id: bus id of the device to be searched
1814  *
1815  * This function searches all devices owned by @cdrv for a device with a bus
1816  * id matching @bus_id.
1817  * Returns:
1818  *  If a match is found, its reference count of the found device is increased
1819  *  and it is returned; else %NULL is returned.
1820  */
1821 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1822                                        const char *bus_id)
1823 {
1824         struct device *dev;
1825         struct device_driver *drv;
1826
1827         drv = get_driver(&cdrv->driver);
1828         if (!drv)
1829                 return NULL;
1830
1831         dev = driver_find_device(drv, NULL, (void *)bus_id,
1832                                  __ccwdev_check_busid);
1833         put_driver(drv);
1834
1835         return dev ? to_ccwdev(dev) : NULL;
1836 }
1837
1838 /************************** device driver handling ************************/
1839
1840 /* This is the implementation of the ccw_driver class. The probe, remove
1841  * and release methods are initially very similar to the device_driver
1842  * implementations, with the difference that they have ccw_device
1843  * arguments.
1844  *
1845  * A ccw driver also contains the information that is needed for
1846  * device matching.
1847  */
1848 static int
1849 ccw_device_probe (struct device *dev)
1850 {
1851         struct ccw_device *cdev = to_ccwdev(dev);
1852         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1853         int ret;
1854
1855         cdev->drv = cdrv; /* to let the driver call _set_online */
1856
1857         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1858
1859         if (ret) {
1860                 cdev->drv = NULL;
1861                 return ret;
1862         }
1863
1864         return 0;
1865 }
1866
1867 static int
1868 ccw_device_remove (struct device *dev)
1869 {
1870         struct ccw_device *cdev = to_ccwdev(dev);
1871         struct ccw_driver *cdrv = cdev->drv;
1872         int ret;
1873
1874         if (cdrv->remove)
1875                 cdrv->remove(cdev);
1876         if (cdev->online) {
1877                 cdev->online = 0;
1878                 spin_lock_irq(cdev->ccwlock);
1879                 ret = ccw_device_offline(cdev);
1880                 spin_unlock_irq(cdev->ccwlock);
1881                 if (ret == 0)
1882                         wait_event(cdev->private->wait_q,
1883                                    dev_fsm_final_state(cdev));
1884                 else
1885                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1886                                       "device 0.%x.%04x\n",
1887                                       ret, cdev->private->dev_id.ssid,
1888                                       cdev->private->dev_id.devno);
1889                 /* Give up reference obtained in ccw_device_set_online(). */
1890                 put_device(&cdev->dev);
1891         }
1892         ccw_device_set_timeout(cdev, 0);
1893         cdev->drv = NULL;
1894         return 0;
1895 }
1896
1897 static void ccw_device_shutdown(struct device *dev)
1898 {
1899         struct ccw_device *cdev;
1900
1901         cdev = to_ccwdev(dev);
1902         if (cdev->drv && cdev->drv->shutdown)
1903                 cdev->drv->shutdown(cdev);
1904         disable_cmf(cdev);
1905 }
1906
1907 static int ccw_device_pm_prepare(struct device *dev)
1908 {
1909         struct ccw_device *cdev = to_ccwdev(dev);
1910
1911         if (work_pending(&cdev->private->kick_work))
1912                 return -EAGAIN;
1913         /* Fail while device is being set online/offline. */
1914         if (atomic_read(&cdev->private->onoff))
1915                 return -EAGAIN;
1916
1917         if (cdev->online && cdev->drv && cdev->drv->prepare)
1918                 return cdev->drv->prepare(cdev);
1919
1920         return 0;
1921 }
1922
1923 static void ccw_device_pm_complete(struct device *dev)
1924 {
1925         struct ccw_device *cdev = to_ccwdev(dev);
1926
1927         if (cdev->online && cdev->drv && cdev->drv->complete)
1928                 cdev->drv->complete(cdev);
1929 }
1930
1931 static int ccw_device_pm_freeze(struct device *dev)
1932 {
1933         struct ccw_device *cdev = to_ccwdev(dev);
1934         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1935         int ret, cm_enabled;
1936
1937         /* Fail suspend while device is in transistional state. */
1938         if (!dev_fsm_final_state(cdev))
1939                 return -EAGAIN;
1940         if (!cdev->online)
1941                 return 0;
1942         if (cdev->drv && cdev->drv->freeze) {
1943                 ret = cdev->drv->freeze(cdev);
1944                 if (ret)
1945                         return ret;
1946         }
1947
1948         spin_lock_irq(sch->lock);
1949         cm_enabled = cdev->private->cmb != NULL;
1950         spin_unlock_irq(sch->lock);
1951         if (cm_enabled) {
1952                 /* Don't have the css write on memory. */
1953                 ret = ccw_set_cmf(cdev, 0);
1954                 if (ret)
1955                         return ret;
1956         }
1957         /* From here on, disallow device driver I/O. */
1958         spin_lock_irq(sch->lock);
1959         ret = cio_disable_subchannel(sch);
1960         spin_unlock_irq(sch->lock);
1961
1962         return ret;
1963 }
1964
1965 static int ccw_device_pm_thaw(struct device *dev)
1966 {
1967         struct ccw_device *cdev = to_ccwdev(dev);
1968         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1969         int ret, cm_enabled;
1970
1971         if (!cdev->online)
1972                 return 0;
1973
1974         spin_lock_irq(sch->lock);
1975         /* Allow device driver I/O again. */
1976         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1977         cm_enabled = cdev->private->cmb != NULL;
1978         spin_unlock_irq(sch->lock);
1979         if (ret)
1980                 return ret;
1981
1982         if (cm_enabled) {
1983                 ret = ccw_set_cmf(cdev, 1);
1984                 if (ret)
1985                         return ret;
1986         }
1987
1988         if (cdev->drv && cdev->drv->thaw)
1989                 ret = cdev->drv->thaw(cdev);
1990
1991         return ret;
1992 }
1993
1994 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1995 {
1996         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1997         int ret;
1998
1999         if (cio_is_console(sch->schid))
2000                 goto out;
2001         /*
2002          * While we were sleeping, devices may have gone or become
2003          * available again. Kick re-detection.
2004          */
2005         spin_lock_irq(sch->lock);
2006         cdev->private->flags.resuming = 1;
2007         ret = ccw_device_recognition(cdev);
2008         spin_unlock_irq(sch->lock);
2009         if (ret) {
2010                 CIO_MSG_EVENT(0, "Couldn't start recognition for device "
2011                               "%s (ret=%d)\n", dev_name(&cdev->dev), ret);
2012                 spin_lock_irq(sch->lock);
2013                 cdev->private->state = DEV_STATE_DISCONNECTED;
2014                 spin_unlock_irq(sch->lock);
2015                 /* notify driver after the resume cb */
2016                 goto out;
2017         }
2018         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
2019                    cdev->private->state == DEV_STATE_DISCONNECTED);
2020
2021 out:
2022         cdev->private->flags.resuming = 0;
2023 }
2024
2025 static int resume_handle_boxed(struct ccw_device *cdev)
2026 {
2027         cdev->private->state = DEV_STATE_BOXED;
2028         if (ccw_device_notify(cdev, CIO_BOXED))
2029                 return 0;
2030         ccw_device_schedule_sch_unregister(cdev);
2031         return -ENODEV;
2032 }
2033
2034 static int resume_handle_disc(struct ccw_device *cdev)
2035 {
2036         cdev->private->state = DEV_STATE_DISCONNECTED;
2037         if (ccw_device_notify(cdev, CIO_GONE))
2038                 return 0;
2039         ccw_device_schedule_sch_unregister(cdev);
2040         return -ENODEV;
2041 }
2042
2043 static int ccw_device_pm_restore(struct device *dev)
2044 {
2045         struct ccw_device *cdev = to_ccwdev(dev);
2046         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2047         int ret = 0, cm_enabled;
2048
2049         __ccw_device_pm_restore(cdev);
2050         spin_lock_irq(sch->lock);
2051         if (cio_is_console(sch->schid)) {
2052                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
2053                 spin_unlock_irq(sch->lock);
2054                 goto out_restore;
2055         }
2056         cdev->private->flags.donotify = 0;
2057         /* check recognition results */
2058         switch (cdev->private->state) {
2059         case DEV_STATE_OFFLINE:
2060                 break;
2061         case DEV_STATE_BOXED:
2062                 ret = resume_handle_boxed(cdev);
2063                 spin_unlock_irq(sch->lock);
2064                 if (ret)
2065                         goto out;
2066                 goto out_restore;
2067         case DEV_STATE_DISCONNECTED:
2068                 goto out_disc_unlock;
2069         default:
2070                 goto out_unreg_unlock;
2071         }
2072         /* check if the device id has changed */
2073         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
2074                 CIO_MSG_EVENT(0, "resume: sch %s: failed (devno changed from "
2075                               "%04x to %04x)\n", dev_name(&sch->dev),
2076                               cdev->private->dev_id.devno,
2077                               sch->schib.pmcw.dev);
2078                 goto out_unreg_unlock;
2079         }
2080         /* check if the device type has changed */
2081         if (!ccw_device_test_sense_data(cdev)) {
2082                 ccw_device_update_sense_data(cdev);
2083                 PREPARE_WORK(&cdev->private->kick_work,
2084                              ccw_device_do_unbind_bind);
2085                 queue_work(ccw_device_work, &cdev->private->kick_work);
2086                 ret = -ENODEV;
2087                 goto out_unlock;
2088         }
2089         if (!cdev->online) {
2090                 ret = 0;
2091                 goto out_unlock;
2092         }
2093         ret = ccw_device_online(cdev);
2094         if (ret)
2095                 goto out_disc_unlock;
2096
2097         cm_enabled = cdev->private->cmb != NULL;
2098         spin_unlock_irq(sch->lock);
2099
2100         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
2101         if (cdev->private->state != DEV_STATE_ONLINE) {
2102                 spin_lock_irq(sch->lock);
2103                 goto out_disc_unlock;
2104         }
2105         if (cm_enabled) {
2106                 ret = ccw_set_cmf(cdev, 1);
2107                 if (ret) {
2108                         CIO_MSG_EVENT(2, "resume: cdev %s: cmf failed "
2109                                       "(rc=%d)\n", dev_name(&cdev->dev), ret);
2110                         ret = 0;
2111                 }
2112         }
2113
2114 out_restore:
2115         if (cdev->online && cdev->drv && cdev->drv->restore)
2116                 ret = cdev->drv->restore(cdev);
2117 out:
2118         return ret;
2119
2120 out_disc_unlock:
2121         ret = resume_handle_disc(cdev);
2122         spin_unlock_irq(sch->lock);
2123         if (ret)
2124                 return ret;
2125         goto out_restore;
2126
2127 out_unreg_unlock:
2128         ccw_device_schedule_sch_unregister(cdev);
2129         ret = -ENODEV;
2130 out_unlock:
2131         spin_unlock_irq(sch->lock);
2132         return ret;
2133 }
2134
2135 static struct dev_pm_ops ccw_pm_ops = {
2136         .prepare = ccw_device_pm_prepare,
2137         .complete = ccw_device_pm_complete,
2138         .freeze = ccw_device_pm_freeze,
2139         .thaw = ccw_device_pm_thaw,
2140         .restore = ccw_device_pm_restore,
2141 };
2142
2143 struct bus_type ccw_bus_type = {
2144         .name   = "ccw",
2145         .match  = ccw_bus_match,
2146         .uevent = ccw_uevent,
2147         .probe  = ccw_device_probe,
2148         .remove = ccw_device_remove,
2149         .shutdown = ccw_device_shutdown,
2150         .pm = &ccw_pm_ops,
2151 };
2152
2153 /**
2154  * ccw_driver_register() - register a ccw driver
2155  * @cdriver: driver to be registered
2156  *
2157  * This function is mainly a wrapper around driver_register().
2158  * Returns:
2159  *   %0 on success and a negative error value on failure.
2160  */
2161 int ccw_driver_register(struct ccw_driver *cdriver)
2162 {
2163         struct device_driver *drv = &cdriver->driver;
2164
2165         drv->bus = &ccw_bus_type;
2166         drv->name = cdriver->name;
2167         drv->owner = cdriver->owner;
2168
2169         return driver_register(drv);
2170 }
2171
2172 /**
2173  * ccw_driver_unregister() - deregister a ccw driver
2174  * @cdriver: driver to be deregistered
2175  *
2176  * This function is mainly a wrapper around driver_unregister().
2177  */
2178 void ccw_driver_unregister(struct ccw_driver *cdriver)
2179 {
2180         driver_unregister(&cdriver->driver);
2181 }
2182
2183 /* Helper func for qdio. */
2184 struct subchannel_id
2185 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2186 {
2187         struct subchannel *sch;
2188
2189         sch = to_subchannel(cdev->dev.parent);
2190         return sch->schid;
2191 }
2192
2193 MODULE_LICENSE("GPL");
2194 EXPORT_SYMBOL(ccw_device_set_online);
2195 EXPORT_SYMBOL(ccw_device_set_offline);
2196 EXPORT_SYMBOL(ccw_driver_register);
2197 EXPORT_SYMBOL(ccw_driver_unregister);
2198 EXPORT_SYMBOL(get_ccwdev_by_busid);
2199 EXPORT_SYMBOL(ccw_bus_type);
2200 EXPORT_SYMBOL(ccw_device_work);
2201 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);