drivers/s390/cio/device.c

   1 /*
   2  *  bus driver for ccw devices
   3  *
   4  *    Copyright IBM Corp. 2002, 2008
   5  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   6  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  */
   9
  10 #define KMSG_COMPONENT "cio"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/list.h>
  20 #include <linux/device.h>
  21 #include <linux/workqueue.h>
  22 #include <linux/delay.h>
  23 #include <linux/timer.h>
  24 #include <linux/kernel_stat.h>
  25
  26 #include <asm/ccwdev.h>
  27 #include <asm/cio.h>
  28 #include <asm/param.h>          /* HZ */
  29 #include <asm/cmb.h>
  30 #include <asm/isc.h>
  31
  32 #include "chp.h"
  33 #include "cio.h"
  34 #include "cio_debug.h"
  35 #include "css.h"
  36 #include "device.h"
  37 #include "ioasm.h"
  38 #include "io_sch.h"
  39 #include "blacklist.h"
  40 #include "chsc.h"
  41
  42 static struct timer_list recovery_timer;
  43 static DEFINE_SPINLOCK(recovery_lock);
  44 static int recovery_phase;
  45 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  46
  47 static atomic_t ccw_device_init_count = ATOMIC_INIT(0);
  48 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq);
  49 static struct bus_type ccw_bus_type;
  50
  51 /******************* bus type handling ***********************/
  52
  53 /* The Linux driver model distinguishes between a bus type and
  54  * the bus itself. Of course we only have one channel
  55  * subsystem driver and one channel system per machine, but
  56  * we still use the abstraction. T.R. says it's a good idea. */
  57 static int
  58 ccw_bus_match (struct device * dev, struct device_driver * drv)
  59 {
  60         struct ccw_device *cdev = to_ccwdev(dev);
  61         struct ccw_driver *cdrv = to_ccwdrv(drv);
  62         const struct ccw_device_id *ids = cdrv->ids, *found;
  63
  64         if (!ids)
  65                 return 0;
  66
  67         found = ccw_device_id_match(ids, &cdev->id);
  68         if (!found)
  69                 return 0;
  70
  71         cdev->id.driver_info = found->driver_info;
  72
  73         return 1;
  74 }
  75
  76 /* Store modalias string delimited by prefix/suffix string into buffer with
  77  * specified size. Return length of resulting string (excluding trailing '\0')
  78  * even if string doesn't fit buffer (snprintf semantics). */
  79 static int snprint_alias(char *buf, size_t size,
  80                          struct ccw_device_id *id, const char *suffix)
  81 {
  82         int len;
  83
  84         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  85         if (len > size)
  86                 return len;
  87         buf += len;
  88         size -= len;
  89
  90         if (id->dev_type != 0)
  91                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  92                                 id->dev_model, suffix);
  93         else
  94                 len += snprintf(buf, size, "dtdm%s", suffix);
  95
  96         return len;
  97 }
  98
  99 /* Set up environment variables for ccw device uevent. Return 0 on success,
 100  * non-zero otherwise. */
 101 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
 102 {
 103         struct ccw_device *cdev = to_ccwdev(dev);
 104         struct ccw_device_id *id = &(cdev->id);
 105         int ret;
 106         char modalias_buf[30];
 107
 108         /* CU_TYPE= */
 109         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 110         if (ret)
 111                 return ret;
 112
 113         /* CU_MODEL= */
 114         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 115         if (ret)
 116                 return ret;
 117
 118         /* The next two can be zero, that's ok for us */
 119         /* DEV_TYPE= */
 120         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 121         if (ret)
 122                 return ret;
 123
 124         /* DEV_MODEL= */
 125         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 126         if (ret)
 127                 return ret;
 128
 129         /* MODALIAS=  */
 130         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 131         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 132         return ret;
 133 }
 134
 135 static void io_subchannel_irq(struct subchannel *);
 136 static int io_subchannel_probe(struct subchannel *);
 137 static int io_subchannel_remove(struct subchannel *);
 138 static void io_subchannel_shutdown(struct subchannel *);
 139 static int io_subchannel_sch_event(struct subchannel *, int);
 140 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 141                                    int);
 142 static void recovery_func(unsigned long data);
 143
 144 static struct css_device_id io_subchannel_ids[] = {
 145         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 146         { /* end of list */ },
 147 };
 148 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 149
 150 static int io_subchannel_prepare(struct subchannel *sch)
 151 {
 152         struct ccw_device *cdev;
 153         /*
 154          * Don't allow suspend while a ccw device registration
 155          * is still outstanding.
 156          */
 157         cdev = sch_get_cdev(sch);
 158         if (cdev && !device_is_registered(&cdev->dev))
 159                 return -EAGAIN;
 160         return 0;
 161 }
 162
 163 static int io_subchannel_settle(void)
 164 {
 165         int ret;
 166
 167         ret = wait_event_interruptible(ccw_device_init_wq,
 168                                 atomic_read(&ccw_device_init_count) == 0);
 169         if (ret)
 170                 return -EINTR;
 171         flush_workqueue(cio_work_q);
 172         return 0;
 173 }
 174
 175 static struct css_driver io_subchannel_driver = {
 176         .drv = {
 177                 .owner = THIS_MODULE,
 178                 .name = "io_subchannel",
 179         },
 180         .subchannel_type = io_subchannel_ids,
 181         .irq = io_subchannel_irq,
 182         .sch_event = io_subchannel_sch_event,
 183         .chp_event = io_subchannel_chp_event,
 184         .probe = io_subchannel_probe,
 185         .remove = io_subchannel_remove,
 186         .shutdown = io_subchannel_shutdown,
 187         .prepare = io_subchannel_prepare,
 188         .settle = io_subchannel_settle,
 189 };
 190
 191 int __init io_subchannel_init(void)
 192 {
 193         int ret;
 194
 195         setup_timer(&recovery_timer, recovery_func, 0);
 196         ret = bus_register(&ccw_bus_type);
 197         if (ret)
 198                 return ret;
 199         ret = css_driver_register(&io_subchannel_driver);
 200         if (ret)
 201                 bus_unregister(&ccw_bus_type);
 202
 203         return ret;
 204 }
 205
 206
 207 /************************ device handling **************************/
 208
 209 /*
 210  * A ccw_device has some interfaces in sysfs in addition to the
 211  * standard ones.
 212  * The following entries are designed to export the information which
 213  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 214  * are obvious, so they don't have an entry :)
 215  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 216  */
 217 static ssize_t
 218 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 219 {
 220         struct subchannel *sch = to_subchannel(dev);
 221         struct chsc_ssd_info *ssd = &sch->ssd_info;
 222         ssize_t ret = 0;
 223         int chp;
 224         int mask;
 225
 226         for (chp = 0; chp < 8; chp++) {
 227                 mask = 0x80 >> chp;
 228                 if (ssd->path_mask & mask)
 229                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 230                 else
 231                         ret += sprintf(buf + ret, "00 ");
 232         }
 233         ret += sprintf (buf+ret, "\n");
 234         return min((ssize_t)PAGE_SIZE, ret);
 235 }
 236
 237 static ssize_t
 238 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 239 {
 240         struct subchannel *sch = to_subchannel(dev);
 241         struct pmcw *pmcw = &sch->schib.pmcw;
 242
 243         return sprintf (buf, "%02x %02x %02x\n",
 244                         pmcw->pim, pmcw->pam, pmcw->pom);
 245 }
 246
 247 static ssize_t
 248 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 249 {
 250         struct ccw_device *cdev = to_ccwdev(dev);
 251         struct ccw_device_id *id = &(cdev->id);
 252
 253         if (id->dev_type != 0)
 254                 return sprintf(buf, "%04x/%02x\n",
 255                                 id->dev_type, id->dev_model);
 256         else
 257                 return sprintf(buf, "n/a\n");
 258 }
 259
 260 static ssize_t
 261 cutype_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         return sprintf(buf, "%04x/%02x\n",
 267                        id->cu_type, id->cu_model);
 268 }
 269
 270 static ssize_t
 271 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 272 {
 273         struct ccw_device *cdev = to_ccwdev(dev);
 274         struct ccw_device_id *id = &(cdev->id);
 275         int len;
 276
 277         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 278
 279         return len > PAGE_SIZE ? PAGE_SIZE : len;
 280 }
 281
 282 static ssize_t
 283 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 284 {
 285         struct ccw_device *cdev = to_ccwdev(dev);
 286
 287         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 288 }
 289
 290 int ccw_device_is_orphan(struct ccw_device *cdev)
 291 {
 292         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 293 }
 294
 295 static void ccw_device_unregister(struct ccw_device *cdev)
 296 {
 297         if (device_is_registered(&cdev->dev)) {
 298                 /* Undo device_add(). */
 299                 device_del(&cdev->dev);
 300         }
 301         if (cdev->private->flags.initialized) {
 302                 cdev->private->flags.initialized = 0;
 303                 /* Release reference from device_initialize(). */
 304                 put_device(&cdev->dev);
 305         }
 306 }
 307
 308 static void io_subchannel_quiesce(struct subchannel *);
 309
 310 /**
 311  * ccw_device_set_offline() - disable a ccw device for I/O
 312  * @cdev: target ccw device
 313  *
 314  * This function calls the driver's set_offline() function for @cdev, if
 315  * given, and then disables @cdev.
 316  * Returns:
 317  *   %0 on success and a negative error value on failure.
 318  * Context:
 319  *  enabled, ccw device lock not held
 320  */
 321 int ccw_device_set_offline(struct ccw_device *cdev)
 322 {
 323         struct subchannel *sch;
 324         int ret, state;
 325
 326         if (!cdev)
 327                 return -ENODEV;
 328         if (!cdev->online || !cdev->drv)
 329                 return -EINVAL;
 330
 331         if (cdev->drv->set_offline) {
 332                 ret = cdev->drv->set_offline(cdev);
 333                 if (ret != 0)
 334                         return ret;
 335         }
 336         spin_lock_irq(cdev->ccwlock);
 337         sch = to_subchannel(cdev->dev.parent);
 338         cdev->online = 0;
 339         /* Wait until a final state or DISCONNECTED is reached */
 340         while (!dev_fsm_final_state(cdev) &&
 341                cdev->private->state != DEV_STATE_DISCONNECTED) {
 342                 spin_unlock_irq(cdev->ccwlock);
 343                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 344                            cdev->private->state == DEV_STATE_DISCONNECTED));
 345                 spin_lock_irq(cdev->ccwlock);
 346         }
 347         do {
 348                 ret = ccw_device_offline(cdev);
 349                 if (!ret)
 350                         break;
 351                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 352                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 353                               cdev->private->dev_id.devno);
 354                 if (ret != -EBUSY)
 355                         goto error;
 356                 state = cdev->private->state;
 357                 spin_unlock_irq(cdev->ccwlock);
 358                 io_subchannel_quiesce(sch);
 359                 spin_lock_irq(cdev->ccwlock);
 360                 cdev->private->state = state;
 361         } while (ret == -EBUSY);
 362         spin_unlock_irq(cdev->ccwlock);
 363         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 364                    cdev->private->state == DEV_STATE_DISCONNECTED));
 365         /* Inform the user if set offline failed. */
 366         if (cdev->private->state == DEV_STATE_BOXED) {
 367                 pr_warn("%s: The device entered boxed state while being set offline\n",
 368                         dev_name(&cdev->dev));
 369         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 370                 pr_warn("%s: The device stopped operating while being set offline\n",
 371                         dev_name(&cdev->dev));
 372         }
 373         /* Give up reference from ccw_device_set_online(). */
 374         put_device(&cdev->dev);
 375         return 0;
 376
 377 error:
 378         cdev->private->state = DEV_STATE_OFFLINE;
 379         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 380         spin_unlock_irq(cdev->ccwlock);
 381         /* Give up reference from ccw_device_set_online(). */
 382         put_device(&cdev->dev);
 383         return -ENODEV;
 384 }
 385
 386 /**
 387  * ccw_device_set_online() - enable a ccw device for I/O
 388  * @cdev: target ccw device
 389  *
 390  * This function first enables @cdev and then calls the driver's set_online()
 391  * function for @cdev, if given. If set_online() returns an error, @cdev is
 392  * disabled again.
 393  * Returns:
 394  *   %0 on success and a negative error value on failure.
 395  * Context:
 396  *  enabled, ccw device lock not held
 397  */
 398 int ccw_device_set_online(struct ccw_device *cdev)
 399 {
 400         int ret;
 401         int ret2;
 402
 403         if (!cdev)
 404                 return -ENODEV;
 405         if (cdev->online || !cdev->drv)
 406                 return -EINVAL;
 407         /* Hold on to an extra reference while device is online. */
 408         if (!get_device(&cdev->dev))
 409                 return -ENODEV;
 410
 411         spin_lock_irq(cdev->ccwlock);
 412         ret = ccw_device_online(cdev);
 413         spin_unlock_irq(cdev->ccwlock);
 414         if (ret == 0)
 415                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 416         else {
 417                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 418                               "device 0.%x.%04x\n",
 419                               ret, cdev->private->dev_id.ssid,
 420                               cdev->private->dev_id.devno);
 421                 /* Give up online reference since onlining failed. */
 422                 put_device(&cdev->dev);
 423                 return ret;
 424         }
 425         spin_lock_irq(cdev->ccwlock);
 426         /* Check if online processing was successful */
 427         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 428             (cdev->private->state != DEV_STATE_W4SENSE)) {
 429                 spin_unlock_irq(cdev->ccwlock);
 430                 /* Inform the user that set online failed. */
 431                 if (cdev->private->state == DEV_STATE_BOXED) {
 432                         pr_warn("%s: Setting the device online failed because it is boxed\n",
 433                                 dev_name(&cdev->dev));
 434                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 435                         pr_warn("%s: Setting the device online failed because it is not operational\n",
 436                                 dev_name(&cdev->dev));
 437                 }
 438                 /* Give up online reference since onlining failed. */
 439                 put_device(&cdev->dev);
 440                 return -ENODEV;
 441         }
 442         spin_unlock_irq(cdev->ccwlock);
 443         if (cdev->drv->set_online)
 444                 ret = cdev->drv->set_online(cdev);
 445         if (ret)
 446                 goto rollback;
 447
 448         spin_lock_irq(cdev->ccwlock);
 449         cdev->online = 1;
 450         spin_unlock_irq(cdev->ccwlock);
 451         return 0;
 452
 453 rollback:
 454         spin_lock_irq(cdev->ccwlock);
 455         /* Wait until a final state or DISCONNECTED is reached */
 456         while (!dev_fsm_final_state(cdev) &&
 457                cdev->private->state != DEV_STATE_DISCONNECTED) {
 458                 spin_unlock_irq(cdev->ccwlock);
 459                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 460                            cdev->private->state == DEV_STATE_DISCONNECTED));
 461                 spin_lock_irq(cdev->ccwlock);
 462         }
 463         ret2 = ccw_device_offline(cdev);
 464         if (ret2)
 465                 goto error;
 466         spin_unlock_irq(cdev->ccwlock);
 467         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 468                    cdev->private->state == DEV_STATE_DISCONNECTED));
 469         /* Give up online reference since onlining failed. */
 470         put_device(&cdev->dev);
 471         return ret;
 472
 473 error:
 474         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 475                       "device 0.%x.%04x\n",
 476                       ret2, cdev->private->dev_id.ssid,
 477                       cdev->private->dev_id.devno);
 478         cdev->private->state = DEV_STATE_OFFLINE;
 479         spin_unlock_irq(cdev->ccwlock);
 480         /* Give up online reference since onlining failed. */
 481         put_device(&cdev->dev);
 482         return ret;
 483 }
 484
 485 static int online_store_handle_offline(struct ccw_device *cdev)
 486 {
 487         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 488                 spin_lock_irq(cdev->ccwlock);
 489                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 490                 spin_unlock_irq(cdev->ccwlock);
 491                 return 0;
 492         }
 493         if (cdev->drv && cdev->drv->set_offline)
 494                 return ccw_device_set_offline(cdev);
 495         return -EINVAL;
 496 }
 497
 498 static int online_store_recog_and_online(struct ccw_device *cdev)
 499 {
 500         /* Do device recognition, if needed. */
 501         if (cdev->private->state == DEV_STATE_BOXED) {
 502                 spin_lock_irq(cdev->ccwlock);
 503                 ccw_device_recognition(cdev);
 504                 spin_unlock_irq(cdev->ccwlock);
 505                 wait_event(cdev->private->wait_q,
 506                            cdev->private->flags.recog_done);
 507                 if (cdev->private->state != DEV_STATE_OFFLINE)
 508                         /* recognition failed */
 509                         return -EAGAIN;
 510         }
 511         if (cdev->drv && cdev->drv->set_online)
 512                 return ccw_device_set_online(cdev);
 513         return -EINVAL;
 514 }
 515
 516 static int online_store_handle_online(struct ccw_device *cdev, int force)
 517 {
 518         int ret;
 519
 520         ret = online_store_recog_and_online(cdev);
 521         if (ret && !force)
 522                 return ret;
 523         if (force && cdev->private->state == DEV_STATE_BOXED) {
 524                 ret = ccw_device_stlck(cdev);
 525                 if (ret)
 526                         return ret;
 527                 if (cdev->id.cu_type == 0)
 528                         cdev->private->state = DEV_STATE_NOT_OPER;
 529                 ret = online_store_recog_and_online(cdev);
 530                 if (ret)
 531                         return ret;
 532         }
 533         return 0;
 534 }
 535
 536 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 537                              const char *buf, size_t count)
 538 {
 539         struct ccw_device *cdev = to_ccwdev(dev);
 540         int force, ret;
 541         unsigned long i;
 542
 543         /* Prevent conflict between multiple on-/offline processing requests. */
 544         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 545                 return -EAGAIN;
 546         /* Prevent conflict between internal I/Os and on-/offline processing. */
 547         if (!dev_fsm_final_state(cdev) &&
 548             cdev->private->state != DEV_STATE_DISCONNECTED) {
 549                 ret = -EAGAIN;
 550                 goto out;
 551         }
 552         /* Prevent conflict between pending work and on-/offline processing.*/
 553         if (work_pending(&cdev->private->todo_work)) {
 554                 ret = -EAGAIN;
 555                 goto out;
 556         }
 557         if (!strncmp(buf, "force\n", count)) {
 558                 force = 1;
 559                 i = 1;
 560                 ret = 0;
 561         } else {
 562                 force = 0;
 563                 ret = kstrtoul(buf, 16, &i);
 564         }
 565         if (ret)
 566                 goto out;
 567
 568         device_lock(dev);
 569         switch (i) {
 570         case 0:
 571                 ret = online_store_handle_offline(cdev);
 572                 break;
 573         case 1:
 574                 ret = online_store_handle_online(cdev, force);
 575                 break;
 576         default:
 577                 ret = -EINVAL;
 578         }
 579         device_unlock(dev);
 580
 581 out:
 582         atomic_set(&cdev->private->onoff, 0);
 583         return (ret < 0) ? ret : count;
 584 }
 585
 586 static ssize_t
 587 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 588 {
 589         struct ccw_device *cdev = to_ccwdev(dev);
 590         struct subchannel *sch;
 591
 592         if (ccw_device_is_orphan(cdev))
 593                 return sprintf(buf, "no device\n");
 594         switch (cdev->private->state) {
 595         case DEV_STATE_BOXED:
 596                 return sprintf(buf, "boxed\n");
 597         case DEV_STATE_DISCONNECTED:
 598         case DEV_STATE_DISCONNECTED_SENSE_ID:
 599         case DEV_STATE_NOT_OPER:
 600                 sch = to_subchannel(dev->parent);
 601                 if (!sch->lpm)
 602                         return sprintf(buf, "no path\n");
 603                 else
 604                         return sprintf(buf, "no device\n");
 605         default:
 606                 /* All other states considered fine. */
 607                 return sprintf(buf, "good\n");
 608         }
 609 }
 610
 611 static ssize_t
 612 initiate_logging(struct device *dev, struct device_attribute *attr,
 613                  const char *buf, size_t count)
 614 {
 615         struct subchannel *sch = to_subchannel(dev);
 616         int rc;
 617
 618         rc = chsc_siosl(sch->schid);
 619         if (rc < 0) {
 620                 pr_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n",
 621                         sch->schid.ssid, sch->schid.sch_no, rc);
 622                 return rc;
 623         }
 624         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 625                   sch->schid.ssid, sch->schid.sch_no);
 626         return count;
 627 }
 628
 629 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
 630                         char *buf)
 631 {
 632         struct subchannel *sch = to_subchannel(dev);
 633
 634         return sprintf(buf, "%02x\n", sch->vpm);
 635 }
 636
 637 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 638 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 639 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 640 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 641 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 642 static DEVICE_ATTR(online, 0644, online_show, online_store);
 643 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 644 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 645 static DEVICE_ATTR(vpm, 0444, vpm_show, NULL);
 646
 647 static struct attribute *io_subchannel_attrs[] = {
 648         &dev_attr_chpids.attr,
 649         &dev_attr_pimpampom.attr,
 650         &dev_attr_logging.attr,
 651         &dev_attr_vpm.attr,
 652         NULL,
 653 };
 654
 655 static struct attribute_group io_subchannel_attr_group = {
 656         .attrs = io_subchannel_attrs,
 657 };
 658
 659 static struct attribute * ccwdev_attrs[] = {
 660         &dev_attr_devtype.attr,
 661         &dev_attr_cutype.attr,
 662         &dev_attr_modalias.attr,
 663         &dev_attr_online.attr,
 664         &dev_attr_cmb_enable.attr,
 665         &dev_attr_availability.attr,
 666         NULL,
 667 };
 668
 669 static struct attribute_group ccwdev_attr_group = {
 670         .attrs = ccwdev_attrs,
 671 };
 672
 673 static const struct attribute_group *ccwdev_attr_groups[] = {
 674         &ccwdev_attr_group,
 675         NULL,
 676 };
 677
 678 static int ccw_device_add(struct ccw_device *cdev)
 679 {
 680         struct device *dev = &cdev->dev;
 681
 682         dev->bus = &ccw_bus_type;
 683         return device_add(dev);
 684 }
 685
 686 static int match_dev_id(struct device *dev, void *data)
 687 {
 688         struct ccw_device *cdev = to_ccwdev(dev);
 689         struct ccw_dev_id *dev_id = data;
 690
 691         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 692 }
 693
 694 /**
 695  * get_ccwdev_by_dev_id() - obtain device from a ccw device id
 696  * @dev_id: id of the device to be searched
 697  *
 698  * This function searches all devices attached to the ccw bus for a device
 699  * matching @dev_id.
 700  * Returns:
 701  *  If a device is found its reference count is increased and returned;
 702  *  else %NULL is returned.
 703  */
 704 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 705 {
 706         struct device *dev;
 707
 708         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 709
 710         return dev ? to_ccwdev(dev) : NULL;
 711 }
 712 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
 713
 714 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 715 {
 716         int ret;
 717
 718         if (device_is_registered(&cdev->dev)) {
 719                 device_release_driver(&cdev->dev);
 720                 ret = device_attach(&cdev->dev);
 721                 WARN_ON(ret == -ENODEV);
 722         }
 723 }
 724
 725 static void
 726 ccw_device_release(struct device *dev)
 727 {
 728         struct ccw_device *cdev;
 729
 730         cdev = to_ccwdev(dev);
 731         /* Release reference of parent subchannel. */
 732         put_device(cdev->dev.parent);
 733         kfree(cdev->private);
 734         kfree(cdev);
 735 }
 736
 737 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 738 {
 739         struct ccw_device *cdev;
 740
 741         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 742         if (cdev) {
 743                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 744                                         GFP_KERNEL | GFP_DMA);
 745                 if (cdev->private)
 746                         return cdev;
 747         }
 748         kfree(cdev);
 749         return ERR_PTR(-ENOMEM);
 750 }
 751
 752 static void ccw_device_todo(struct work_struct *work);
 753
 754 static int io_subchannel_initialize_dev(struct subchannel *sch,
 755                                         struct ccw_device *cdev)
 756 {
 757         struct ccw_device_private *priv = cdev->private;
 758         int ret;
 759
 760         priv->cdev = cdev;
 761         priv->int_class = IRQIO_CIO;
 762         priv->state = DEV_STATE_NOT_OPER;
 763         priv->dev_id.devno = sch->schib.pmcw.dev;
 764         priv->dev_id.ssid = sch->schid.ssid;
 765
 766         INIT_WORK(&priv->todo_work, ccw_device_todo);
 767         INIT_LIST_HEAD(&priv->cmb_list);
 768         init_waitqueue_head(&priv->wait_q);
 769         init_timer(&priv->timer);
 770
 771         atomic_set(&priv->onoff, 0);
 772         cdev->ccwlock = sch->lock;
 773         cdev->dev.parent = &sch->dev;
 774         cdev->dev.release = ccw_device_release;
 775         cdev->dev.groups = ccwdev_attr_groups;
 776         /* Do first half of device_register. */
 777         device_initialize(&cdev->dev);
 778         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 779                            cdev->private->dev_id.devno);
 780         if (ret)
 781                 goto out_put;
 782         if (!get_device(&sch->dev)) {
 783                 ret = -ENODEV;
 784                 goto out_put;
 785         }
 786         priv->flags.initialized = 1;
 787         spin_lock_irq(sch->lock);
 788         sch_set_cdev(sch, cdev);
 789         spin_unlock_irq(sch->lock);
 790         return 0;
 791
 792 out_put:
 793         /* Release reference from device_initialize(). */
 794         put_device(&cdev->dev);
 795         return ret;
 796 }
 797
 798 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 799 {
 800         struct ccw_device *cdev;
 801         int ret;
 802
 803         cdev = io_subchannel_allocate_dev(sch);
 804         if (!IS_ERR(cdev)) {
 805                 ret = io_subchannel_initialize_dev(sch, cdev);
 806                 if (ret)
 807                         cdev = ERR_PTR(ret);
 808         }
 809         return cdev;
 810 }
 811
 812 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 813
 814 static void sch_create_and_recog_new_device(struct subchannel *sch)
 815 {
 816         struct ccw_device *cdev;
 817
 818         /* Need to allocate a new ccw device. */
 819         cdev = io_subchannel_create_ccwdev(sch);
 820         if (IS_ERR(cdev)) {
 821                 /* OK, we did everything we could... */
 822                 css_sch_device_unregister(sch);
 823                 return;
 824         }
 825         /* Start recognition for the new ccw device. */
 826         io_subchannel_recog(cdev, sch);
 827 }
 828
 829 /*
 830  * Register recognized device.
 831  */
 832 static void io_subchannel_register(struct ccw_device *cdev)
 833 {
 834         struct subchannel *sch;
 835         int ret, adjust_init_count = 1;
 836         unsigned long flags;
 837
 838         sch = to_subchannel(cdev->dev.parent);
 839         /*
 840          * Check if subchannel is still registered. It may have become
 841          * unregistered if a machine check hit us after finishing
 842          * device recognition but before the register work could be
 843          * queued.
 844          */
 845         if (!device_is_registered(&sch->dev))
 846                 goto out_err;
 847         css_update_ssd_info(sch);
 848         /*
 849          * io_subchannel_register() will also be called after device
 850          * recognition has been done for a boxed device (which will already
 851          * be registered). We need to reprobe since we may now have sense id
 852          * information.
 853          */
 854         if (device_is_registered(&cdev->dev)) {
 855                 if (!cdev->drv) {
 856                         ret = device_reprobe(&cdev->dev);
 857                         if (ret)
 858                                 /* We can't do much here. */
 859                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 860                                               " %d for 0.%x.%04x\n", ret,
 861                                               cdev->private->dev_id.ssid,
 862                                               cdev->private->dev_id.devno);
 863                 }
 864                 adjust_init_count = 0;
 865                 goto out;
 866         }
 867         /*
 868          * Now we know this subchannel will stay, we can throw
 869          * our delayed uevent.
 870          */
 871         dev_set_uevent_suppress(&sch->dev, 0);
 872         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 873         /* make it known to the system */
 874         ret = ccw_device_add(cdev);
 875         if (ret) {
 876                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 877                               cdev->private->dev_id.ssid,
 878                               cdev->private->dev_id.devno, ret);
 879                 spin_lock_irqsave(sch->lock, flags);
 880                 sch_set_cdev(sch, NULL);
 881                 spin_unlock_irqrestore(sch->lock, flags);
 882                 /* Release initial device reference. */
 883                 put_device(&cdev->dev);
 884                 goto out_err;
 885         }
 886 out:
 887         cdev->private->flags.recog_done = 1;
 888         wake_up(&cdev->private->wait_q);
 889 out_err:
 890         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 891                 wake_up(&ccw_device_init_wq);
 892 }
 893
 894 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 895 {
 896         struct subchannel *sch;
 897
 898         /* Get subchannel reference for local processing. */
 899         if (!get_device(cdev->dev.parent))
 900                 return;
 901         sch = to_subchannel(cdev->dev.parent);
 902         css_sch_device_unregister(sch);
 903         /* Release subchannel reference for local processing. */
 904         put_device(&sch->dev);
 905 }
 906
 907 /*
 908  * subchannel recognition done. Called from the state machine.
 909  */
 910 void
 911 io_subchannel_recog_done(struct ccw_device *cdev)
 912 {
 913         if (css_init_done == 0) {
 914                 cdev->private->flags.recog_done = 1;
 915                 return;
 916         }
 917         switch (cdev->private->state) {
 918         case DEV_STATE_BOXED:
 919                 /* Device did not respond in time. */
 920         case DEV_STATE_NOT_OPER:
 921                 cdev->private->flags.recog_done = 1;
 922                 /* Remove device found not operational. */
 923                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 924                 if (atomic_dec_and_test(&ccw_device_init_count))
 925                         wake_up(&ccw_device_init_wq);
 926                 break;
 927         case DEV_STATE_OFFLINE:
 928                 /*
 929                  * We can't register the device in interrupt context so
 930                  * we schedule a work item.
 931                  */
 932                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 933                 break;
 934         }
 935 }
 936
 937 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 938 {
 939         /* Increase counter of devices currently in recognition. */
 940         atomic_inc(&ccw_device_init_count);
 941
 942         /* Start async. device sensing. */
 943         spin_lock_irq(sch->lock);
 944         ccw_device_recognition(cdev);
 945         spin_unlock_irq(sch->lock);
 946 }
 947
 948 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 949                                   struct subchannel *sch)
 950 {
 951         struct subchannel *old_sch;
 952         int rc, old_enabled = 0;
 953
 954         old_sch = to_subchannel(cdev->dev.parent);
 955         /* Obtain child reference for new parent. */
 956         if (!get_device(&sch->dev))
 957                 return -ENODEV;
 958
 959         if (!sch_is_pseudo_sch(old_sch)) {
 960                 spin_lock_irq(old_sch->lock);
 961                 old_enabled = old_sch->schib.pmcw.ena;
 962                 rc = 0;
 963                 if (old_enabled)
 964                         rc = cio_disable_subchannel(old_sch);
 965                 spin_unlock_irq(old_sch->lock);
 966                 if (rc == -EBUSY) {
 967                         /* Release child reference for new parent. */
 968                         put_device(&sch->dev);
 969                         return rc;
 970                 }
 971         }
 972
 973         mutex_lock(&sch->reg_mutex);
 974         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 975         mutex_unlock(&sch->reg_mutex);
 976         if (rc) {
 977                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 978                               cdev->private->dev_id.ssid,
 979                               cdev->private->dev_id.devno, sch->schid.ssid,
 980                               sch->schib.pmcw.dev, rc);
 981                 if (old_enabled) {
 982                         /* Try to reenable the old subchannel. */
 983                         spin_lock_irq(old_sch->lock);
 984                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 985                         spin_unlock_irq(old_sch->lock);
 986                 }
 987                 /* Release child reference for new parent. */
 988                 put_device(&sch->dev);
 989                 return rc;
 990         }
 991         /* Clean up old subchannel. */
 992         if (!sch_is_pseudo_sch(old_sch)) {
 993                 spin_lock_irq(old_sch->lock);
 994                 sch_set_cdev(old_sch, NULL);
 995                 spin_unlock_irq(old_sch->lock);
 996                 css_schedule_eval(old_sch->schid);
 997         }
 998         /* Release child reference for old parent. */
 999         put_device(&old_sch->dev);
1000         /* Initialize new subchannel. */
1001         spin_lock_irq(sch->lock);
1002         cdev->ccwlock = sch->lock;
1003         if (!sch_is_pseudo_sch(sch))
1004                 sch_set_cdev(sch, cdev);
1005         spin_unlock_irq(sch->lock);
1006         if (!sch_is_pseudo_sch(sch))
1007                 css_update_ssd_info(sch);
1008         return 0;
1009 }
1010
1011 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1012 {
1013         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1014         struct channel_subsystem *css = to_css(sch->dev.parent);
1015
1016         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1017 }
1018
1019 static void io_subchannel_irq(struct subchannel *sch)
1020 {
1021         struct ccw_device *cdev;
1022
1023         cdev = sch_get_cdev(sch);
1024
1025         CIO_TRACE_EVENT(6, "IRQ");
1026         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1027         if (cdev)
1028                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1029         else
1030                 inc_irq_stat(IRQIO_CIO);
1031 }
1032
1033 void io_subchannel_init_config(struct subchannel *sch)
1034 {
1035         memset(&sch->config, 0, sizeof(sch->config));
1036         sch->config.csense = 1;
1037 }
1038
1039 static void io_subchannel_init_fields(struct subchannel *sch)
1040 {
1041         if (cio_is_console(sch->schid))
1042                 sch->opm = 0xff;
1043         else
1044                 sch->opm = chp_get_sch_opm(sch);
1045         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1046         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1047
1048         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1049                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1050                       sch->schib.pmcw.dev, sch->schid.ssid,
1051                       sch->schid.sch_no, sch->schib.pmcw.pim,
1052                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1053
1054         io_subchannel_init_config(sch);
1055 }
1056
1057 /*
1058  * Note: We always return 0 so that we bind to the device even on error.
1059  * This is needed so that our remove function is called on unregister.
1060  */
1061 static int io_subchannel_probe(struct subchannel *sch)
1062 {
1063         struct io_subchannel_private *io_priv;
1064         struct ccw_device *cdev;
1065         int rc;
1066
1067         if (cio_is_console(sch->schid)) {
1068                 rc = sysfs_create_group(&sch->dev.kobj,
1069                                         &io_subchannel_attr_group);
1070                 if (rc)
1071                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1072                                       "attributes for subchannel "
1073                                       "0.%x.%04x (rc=%d)\n",
1074                                       sch->schid.ssid, sch->schid.sch_no, rc);
1075                 /*
1076                  * The console subchannel already has an associated ccw_device.
1077                  * Throw the delayed uevent for the subchannel, register
1078                  * the ccw_device and exit.
1079                  */
1080                 dev_set_uevent_suppress(&sch->dev, 0);
1081                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1082                 cdev = sch_get_cdev(sch);
1083                 rc = ccw_device_add(cdev);
1084                 if (rc) {
1085                         /* Release online reference. */
1086                         put_device(&cdev->dev);
1087                         goto out_schedule;
1088                 }
1089                 if (atomic_dec_and_test(&ccw_device_init_count))
1090                         wake_up(&ccw_device_init_wq);
1091                 return 0;
1092         }
1093         io_subchannel_init_fields(sch);
1094         rc = cio_commit_config(sch);
1095         if (rc)
1096                 goto out_schedule;
1097         rc = sysfs_create_group(&sch->dev.kobj,
1098                                 &io_subchannel_attr_group);
1099         if (rc)
1100                 goto out_schedule;
1101         /* Allocate I/O subchannel private data. */
1102         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1103         if (!io_priv)
1104                 goto out_schedule;
1105
1106         set_io_private(sch, io_priv);
1107         css_schedule_eval(sch->schid);
1108         return 0;
1109
1110 out_schedule:
1111         spin_lock_irq(sch->lock);
1112         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1113         spin_unlock_irq(sch->lock);
1114         return 0;
1115 }
1116
1117 static int
1118 io_subchannel_remove (struct subchannel *sch)
1119 {
1120         struct io_subchannel_private *io_priv = to_io_private(sch);
1121         struct ccw_device *cdev;
1122
1123         cdev = sch_get_cdev(sch);
1124         if (!cdev)
1125                 goto out_free;
1126         io_subchannel_quiesce(sch);
1127         /* Set ccw device to not operational and drop reference. */
1128         spin_lock_irq(cdev->ccwlock);
1129         sch_set_cdev(sch, NULL);
1130         set_io_private(sch, NULL);
1131         cdev->private->state = DEV_STATE_NOT_OPER;
1132         spin_unlock_irq(cdev->ccwlock);
1133         ccw_device_unregister(cdev);
1134 out_free:
1135         kfree(io_priv);
1136         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1137         return 0;
1138 }
1139
1140 static void io_subchannel_verify(struct subchannel *sch)
1141 {
1142         struct ccw_device *cdev;
1143
1144         cdev = sch_get_cdev(sch);
1145         if (cdev)
1146                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1147 }
1148
1149 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1150 {
1151         struct ccw_device *cdev;
1152
1153         cdev = sch_get_cdev(sch);
1154         if (!cdev)
1155                 return;
1156         if (cio_update_schib(sch))
1157                 goto err;
1158         /* Check for I/O on path. */
1159         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1160                 goto out;
1161         if (cdev->private->state == DEV_STATE_ONLINE) {
1162                 ccw_device_kill_io(cdev);
1163                 goto out;
1164         }
1165         if (cio_clear(sch))
1166                 goto err;
1167 out:
1168         /* Trigger path verification. */
1169         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1170         return;
1171
1172 err:
1173         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1174 }
1175
1176 static int io_subchannel_chp_event(struct subchannel *sch,
1177                                    struct chp_link *link, int event)
1178 {
1179         struct ccw_device *cdev = sch_get_cdev(sch);
1180         int mask;
1181
1182         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1183         if (!mask)
1184                 return 0;
1185         switch (event) {
1186         case CHP_VARY_OFF:
1187                 sch->opm &= ~mask;
1188                 sch->lpm &= ~mask;
1189                 if (cdev)
1190                         cdev->private->path_gone_mask |= mask;
1191                 io_subchannel_terminate_path(sch, mask);
1192                 break;
1193         case CHP_VARY_ON:
1194                 sch->opm |= mask;
1195                 sch->lpm |= mask;
1196                 if (cdev)
1197                         cdev->private->path_new_mask |= mask;
1198                 io_subchannel_verify(sch);
1199                 break;
1200         case CHP_OFFLINE:
1201                 if (cio_update_schib(sch))
1202                         return -ENODEV;
1203                 if (cdev)
1204                         cdev->private->path_gone_mask |= mask;
1205                 io_subchannel_terminate_path(sch, mask);
1206                 break;
1207         case CHP_ONLINE:
1208                 if (cio_update_schib(sch))
1209                         return -ENODEV;
1210                 sch->lpm |= mask & sch->opm;
1211                 if (cdev)
1212                         cdev->private->path_new_mask |= mask;
1213                 io_subchannel_verify(sch);
1214                 break;
1215         }
1216         return 0;
1217 }
1218
1219 static void io_subchannel_quiesce(struct subchannel *sch)
1220 {
1221         struct ccw_device *cdev;
1222         int ret;
1223
1224         spin_lock_irq(sch->lock);
1225         cdev = sch_get_cdev(sch);
1226         if (cio_is_console(sch->schid))
1227                 goto out_unlock;
1228         if (!sch->schib.pmcw.ena)
1229                 goto out_unlock;
1230         ret = cio_disable_subchannel(sch);
1231         if (ret != -EBUSY)
1232                 goto out_unlock;
1233         if (cdev->handler)
1234                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1235         while (ret == -EBUSY) {
1236                 cdev->private->state = DEV_STATE_QUIESCE;
1237                 cdev->private->iretry = 255;
1238                 ret = ccw_device_cancel_halt_clear(cdev);
1239                 if (ret == -EBUSY) {
1240                         ccw_device_set_timeout(cdev, HZ/10);
1241                         spin_unlock_irq(sch->lock);
1242                         wait_event(cdev->private->wait_q,
1243                                    cdev->private->state != DEV_STATE_QUIESCE);
1244                         spin_lock_irq(sch->lock);
1245                 }
1246                 ret = cio_disable_subchannel(sch);
1247         }
1248 out_unlock:
1249         spin_unlock_irq(sch->lock);
1250 }
1251
1252 static void io_subchannel_shutdown(struct subchannel *sch)
1253 {
1254         io_subchannel_quiesce(sch);
1255 }
1256
1257 static int device_is_disconnected(struct ccw_device *cdev)
1258 {
1259         if (!cdev)
1260                 return 0;
1261         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1262                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1263 }
1264
1265 static int recovery_check(struct device *dev, void *data)
1266 {
1267         struct ccw_device *cdev = to_ccwdev(dev);
1268         int *redo = data;
1269
1270         spin_lock_irq(cdev->ccwlock);
1271         switch (cdev->private->state) {
1272         case DEV_STATE_DISCONNECTED:
1273                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1274                               cdev->private->dev_id.ssid,
1275                               cdev->private->dev_id.devno);
1276                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1277                 *redo = 1;
1278                 break;
1279         case DEV_STATE_DISCONNECTED_SENSE_ID:
1280                 *redo = 1;
1281                 break;
1282         }
1283         spin_unlock_irq(cdev->ccwlock);
1284
1285         return 0;
1286 }
1287
1288 static void recovery_work_func(struct work_struct *unused)
1289 {
1290         int redo = 0;
1291
1292         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1293         if (redo) {
1294                 spin_lock_irq(&recovery_lock);
1295                 if (!timer_pending(&recovery_timer)) {
1296                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1297                                 recovery_phase++;
1298                         mod_timer(&recovery_timer, jiffies +
1299                                   recovery_delay[recovery_phase] * HZ);
1300                 }
1301                 spin_unlock_irq(&recovery_lock);
1302         } else
1303                 CIO_MSG_EVENT(4, "recovery: end\n");
1304 }
1305
1306 static DECLARE_WORK(recovery_work, recovery_work_func);
1307
1308 static void recovery_func(unsigned long data)
1309 {
1310         /*
1311          * We can't do our recovery in softirq context and it's not
1312          * performance critical, so we schedule it.
1313          */
1314         schedule_work(&recovery_work);
1315 }
1316
1317 static void ccw_device_schedule_recovery(void)
1318 {
1319         unsigned long flags;
1320
1321         CIO_MSG_EVENT(4, "recovery: schedule\n");
1322         spin_lock_irqsave(&recovery_lock, flags);
1323         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1324                 recovery_phase = 0;
1325                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1326         }
1327         spin_unlock_irqrestore(&recovery_lock, flags);
1328 }
1329
1330 static int purge_fn(struct device *dev, void *data)
1331 {
1332         struct ccw_device *cdev = to_ccwdev(dev);
1333         struct ccw_dev_id *id = &cdev->private->dev_id;
1334
1335         spin_lock_irq(cdev->ccwlock);
1336         if (is_blacklisted(id->ssid, id->devno) &&
1337             (cdev->private->state == DEV_STATE_OFFLINE) &&
1338             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1339                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1340                               id->devno);
1341                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1342                 atomic_set(&cdev->private->onoff, 0);
1343         }
1344         spin_unlock_irq(cdev->ccwlock);
1345         /* Abort loop in case of pending signal. */
1346         if (signal_pending(current))
1347                 return -EINTR;
1348
1349         return 0;
1350 }
1351
1352 /**
1353  * ccw_purge_blacklisted - purge unused, blacklisted devices
1354  *
1355  * Unregister all ccw devices that are offline and on the blacklist.
1356  */
1357 int ccw_purge_blacklisted(void)
1358 {
1359         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1360         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1361         return 0;
1362 }
1363
1364 void ccw_device_set_disconnected(struct ccw_device *cdev)
1365 {
1366         if (!cdev)
1367                 return;
1368         ccw_device_set_timeout(cdev, 0);
1369         cdev->private->flags.fake_irb = 0;
1370         cdev->private->state = DEV_STATE_DISCONNECTED;
1371         if (cdev->online)
1372                 ccw_device_schedule_recovery();
1373 }
1374
1375 void ccw_device_set_notoper(struct ccw_device *cdev)
1376 {
1377         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1378
1379         CIO_TRACE_EVENT(2, "notoper");
1380         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1381         ccw_device_set_timeout(cdev, 0);
1382         cio_disable_subchannel(sch);
1383         cdev->private->state = DEV_STATE_NOT_OPER;
1384 }
1385
1386 enum io_sch_action {
1387         IO_SCH_UNREG,
1388         IO_SCH_ORPH_UNREG,
1389         IO_SCH_ATTACH,
1390         IO_SCH_UNREG_ATTACH,
1391         IO_SCH_ORPH_ATTACH,
1392         IO_SCH_REPROBE,
1393         IO_SCH_VERIFY,
1394         IO_SCH_DISC,
1395         IO_SCH_NOP,
1396 };
1397
1398 static enum io_sch_action sch_get_action(struct subchannel *sch)
1399 {
1400         struct ccw_device *cdev;
1401
1402         cdev = sch_get_cdev(sch);
1403         if (cio_update_schib(sch)) {
1404                 /* Not operational. */
1405                 if (!cdev)
1406                         return IO_SCH_UNREG;
1407                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1408                         return IO_SCH_UNREG;
1409                 return IO_SCH_ORPH_UNREG;
1410         }
1411         /* Operational. */
1412         if (!cdev)
1413                 return IO_SCH_ATTACH;
1414         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1415                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1416                         return IO_SCH_UNREG_ATTACH;
1417                 return IO_SCH_ORPH_ATTACH;
1418         }
1419         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1420                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1421                         return IO_SCH_UNREG;
1422                 return IO_SCH_DISC;
1423         }
1424         if (device_is_disconnected(cdev))
1425                 return IO_SCH_REPROBE;
1426         if (cdev->online && !cdev->private->flags.resuming)
1427                 return IO_SCH_VERIFY;
1428         if (cdev->private->state == DEV_STATE_NOT_OPER)
1429                 return IO_SCH_UNREG_ATTACH;
1430         return IO_SCH_NOP;
1431 }
1432
1433 /**
1434  * io_subchannel_sch_event - process subchannel event
1435  * @sch: subchannel
1436  * @process: non-zero if function is called in process context
1437  *
1438  * An unspecified event occurred for this subchannel. Adjust data according
1439  * to the current operational state of the subchannel and device. Return
1440  * zero when the event has been handled sufficiently or -EAGAIN when this
1441  * function should be called again in process context.
1442  */
1443 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1444 {
1445         unsigned long flags;
1446         struct ccw_device *cdev;
1447         struct ccw_dev_id dev_id;
1448         enum io_sch_action action;
1449         int rc = -EAGAIN;
1450
1451         spin_lock_irqsave(sch->lock, flags);
1452         if (!device_is_registered(&sch->dev))
1453                 goto out_unlock;
1454         if (work_pending(&sch->todo_work))
1455                 goto out_unlock;
1456         cdev = sch_get_cdev(sch);
1457         if (cdev && work_pending(&cdev->private->todo_work))
1458                 goto out_unlock;
1459         action = sch_get_action(sch);
1460         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1461                       sch->schid.ssid, sch->schid.sch_no, process,
1462                       action);
1463         /* Perform immediate actions while holding the lock. */
1464         switch (action) {
1465         case IO_SCH_REPROBE:
1466                 /* Trigger device recognition. */
1467                 ccw_device_trigger_reprobe(cdev);
1468                 rc = 0;
1469                 goto out_unlock;
1470         case IO_SCH_VERIFY:
1471                 /* Trigger path verification. */
1472                 io_subchannel_verify(sch);
1473                 rc = 0;
1474                 goto out_unlock;
1475         case IO_SCH_DISC:
1476                 ccw_device_set_disconnected(cdev);
1477                 rc = 0;
1478                 goto out_unlock;
1479         case IO_SCH_ORPH_UNREG:
1480         case IO_SCH_ORPH_ATTACH:
1481                 ccw_device_set_disconnected(cdev);
1482                 break;
1483         case IO_SCH_UNREG_ATTACH:
1484         case IO_SCH_UNREG:
1485                 if (!cdev)
1486                         break;
1487                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1488                         /*
1489                          * Note: delayed work triggered by this event
1490                          * and repeated calls to sch_event are synchronized
1491                          * by the above check for work_pending(cdev).
1492                          */
1493                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1494                 } else
1495                         ccw_device_set_notoper(cdev);
1496                 break;
1497         case IO_SCH_NOP:
1498                 rc = 0;
1499                 goto out_unlock;
1500         default:
1501                 break;
1502         }
1503         spin_unlock_irqrestore(sch->lock, flags);
1504         /* All other actions require process context. */
1505         if (!process)
1506                 goto out;
1507         /* Handle attached ccw device. */
1508         switch (action) {
1509         case IO_SCH_ORPH_UNREG:
1510         case IO_SCH_ORPH_ATTACH:
1511                 /* Move ccw device to orphanage. */
1512                 rc = ccw_device_move_to_orph(cdev);
1513                 if (rc)
1514                         goto out;
1515                 break;
1516         case IO_SCH_UNREG_ATTACH:
1517                 spin_lock_irqsave(sch->lock, flags);
1518                 if (cdev->private->flags.resuming) {
1519                         /* Device will be handled later. */
1520                         rc = 0;
1521                         goto out_unlock;
1522                 }
1523                 sch_set_cdev(sch, NULL);
1524                 spin_unlock_irqrestore(sch->lock, flags);
1525                 /* Unregister ccw device. */
1526                 ccw_device_unregister(cdev);
1527                 break;
1528         default:
1529                 break;
1530         }
1531         /* Handle subchannel. */
1532         switch (action) {
1533         case IO_SCH_ORPH_UNREG:
1534         case IO_SCH_UNREG:
1535                 if (!cdev || !cdev->private->flags.resuming)
1536                         css_sch_device_unregister(sch);
1537                 break;
1538         case IO_SCH_ORPH_ATTACH:
1539         case IO_SCH_UNREG_ATTACH:
1540         case IO_SCH_ATTACH:
1541                 dev_id.ssid = sch->schid.ssid;
1542                 dev_id.devno = sch->schib.pmcw.dev;
1543                 cdev = get_ccwdev_by_dev_id(&dev_id);
1544                 if (!cdev) {
1545                         sch_create_and_recog_new_device(sch);
1546                         break;
1547                 }
1548                 rc = ccw_device_move_to_sch(cdev, sch);
1549                 if (rc) {
1550                         /* Release reference from get_ccwdev_by_dev_id() */
1551                         put_device(&cdev->dev);
1552                         goto out;
1553                 }
1554                 spin_lock_irqsave(sch->lock, flags);
1555                 ccw_device_trigger_reprobe(cdev);
1556                 spin_unlock_irqrestore(sch->lock, flags);
1557                 /* Release reference from get_ccwdev_by_dev_id() */
1558                 put_device(&cdev->dev);
1559                 break;
1560         default:
1561                 break;
1562         }
1563         return 0;
1564
1565 out_unlock:
1566         spin_unlock_irqrestore(sch->lock, flags);
1567 out:
1568         return rc;
1569 }
1570
1571 static void ccw_device_set_int_class(struct ccw_device *cdev)
1572 {
1573         struct ccw_driver *cdrv = cdev->drv;
1574
1575         /* Note: we interpret class 0 in this context as an uninitialized
1576          * field since it translates to a non-I/O interrupt class. */
1577         if (cdrv->int_class != 0)
1578                 cdev->private->int_class = cdrv->int_class;
1579         else
1580                 cdev->private->int_class = IRQIO_CIO;
1581 }
1582
1583 #ifdef CONFIG_CCW_CONSOLE
1584 int __init ccw_device_enable_console(struct ccw_device *cdev)
1585 {
1586         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1587         int rc;
1588
1589         if (!cdev->drv || !cdev->handler)
1590                 return -EINVAL;
1591
1592         io_subchannel_init_fields(sch);
1593         rc = cio_commit_config(sch);
1594         if (rc)
1595                 return rc;
1596         sch->driver = &io_subchannel_driver;
1597         io_subchannel_recog(cdev, sch);
1598         /* Now wait for the async. recognition to come to an end. */
1599         spin_lock_irq(cdev->ccwlock);
1600         while (!dev_fsm_final_state(cdev))
1601                 ccw_device_wait_idle(cdev);
1602
1603         /* Hold on to an extra reference while device is online. */
1604         get_device(&cdev->dev);
1605         rc = ccw_device_online(cdev);
1606         if (rc)
1607                 goto out_unlock;
1608
1609         while (!dev_fsm_final_state(cdev))
1610                 ccw_device_wait_idle(cdev);
1611
1612         if (cdev->private->state == DEV_STATE_ONLINE)
1613                 cdev->online = 1;
1614         else
1615                 rc = -EIO;
1616 out_unlock:
1617         spin_unlock_irq(cdev->ccwlock);
1618         if (rc) /* Give up online reference since onlining failed. */
1619                 put_device(&cdev->dev);
1620         return rc;
1621 }
1622
1623 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1624 {
1625         struct io_subchannel_private *io_priv;
1626         struct ccw_device *cdev;
1627         struct subchannel *sch;
1628
1629         sch = cio_probe_console();
1630         if (IS_ERR(sch))
1631                 return ERR_CAST(sch);
1632
1633         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1634         if (!io_priv) {
1635                 put_device(&sch->dev);
1636                 return ERR_PTR(-ENOMEM);
1637         }
1638         set_io_private(sch, io_priv);
1639         cdev = io_subchannel_create_ccwdev(sch);
1640         if (IS_ERR(cdev)) {
1641                 put_device(&sch->dev);
1642                 kfree(io_priv);
1643                 return cdev;
1644         }
1645         cdev->drv = drv;
1646         ccw_device_set_int_class(cdev);
1647         return cdev;
1648 }
1649
1650 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1651 {
1652         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1653         struct io_subchannel_private *io_priv = to_io_private(sch);
1654
1655         set_io_private(sch, NULL);
1656         put_device(&sch->dev);
1657         put_device(&cdev->dev);
1658         kfree(io_priv);
1659 }
1660
1661 /**
1662  * ccw_device_wait_idle() - busy wait for device to become idle
1663  * @cdev: ccw device
1664  *
1665  * Poll until activity control is zero, that is, no function or data
1666  * transfer is pending/active.
1667  * Called with device lock being held.
1668  */
1669 void ccw_device_wait_idle(struct ccw_device *cdev)
1670 {
1671         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1672
1673         while (1) {
1674                 cio_tsch(sch);
1675                 if (sch->schib.scsw.cmd.actl == 0)
1676                         break;
1677                 udelay_simple(100);
1678         }
1679 }
1680
1681 static int ccw_device_pm_restore(struct device *dev);
1682
1683 int ccw_device_force_console(struct ccw_device *cdev)
1684 {
1685         return ccw_device_pm_restore(&cdev->dev);
1686 }
1687 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1688 #endif
1689
1690 /*
1691  * get ccw_device matching the busid, but only if owned by cdrv
1692  */
1693 static int
1694 __ccwdev_check_busid(struct device *dev, void *id)
1695 {
1696         char *bus_id;
1697
1698         bus_id = id;
1699
1700         return (strcmp(bus_id, dev_name(dev)) == 0);
1701 }
1702
1703
1704 /**
1705  * get_ccwdev_by_busid() - obtain device from a bus id
1706  * @cdrv: driver the device is owned by
1707  * @bus_id: bus id of the device to be searched
1708  *
1709  * This function searches all devices owned by @cdrv for a device with a bus
1710  * id matching @bus_id.
1711  * Returns:
1712  *  If a match is found, its reference count of the found device is increased
1713  *  and it is returned; else %NULL is returned.
1714  */
1715 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1716                                        const char *bus_id)
1717 {
1718         struct device *dev;
1719
1720         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1721                                  __ccwdev_check_busid);
1722
1723         return dev ? to_ccwdev(dev) : NULL;
1724 }
1725
1726 /************************** device driver handling ************************/
1727
1728 /* This is the implementation of the ccw_driver class. The probe, remove
1729  * and release methods are initially very similar to the device_driver
1730  * implementations, with the difference that they have ccw_device
1731  * arguments.
1732  *
1733  * A ccw driver also contains the information that is needed for
1734  * device matching.
1735  */
1736 static int
1737 ccw_device_probe (struct device *dev)
1738 {
1739         struct ccw_device *cdev = to_ccwdev(dev);
1740         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1741         int ret;
1742
1743         cdev->drv = cdrv; /* to let the driver call _set_online */
1744         ccw_device_set_int_class(cdev);
1745         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1746         if (ret) {
1747                 cdev->drv = NULL;
1748                 cdev->private->int_class = IRQIO_CIO;
1749                 return ret;
1750         }
1751
1752         return 0;
1753 }
1754
1755 static int ccw_device_remove(struct device *dev)
1756 {
1757         struct ccw_device *cdev = to_ccwdev(dev);
1758         struct ccw_driver *cdrv = cdev->drv;
1759         int ret;
1760
1761         if (cdrv->remove)
1762                 cdrv->remove(cdev);
1763
1764         spin_lock_irq(cdev->ccwlock);
1765         if (cdev->online) {
1766                 cdev->online = 0;
1767                 ret = ccw_device_offline(cdev);
1768                 spin_unlock_irq(cdev->ccwlock);
1769                 if (ret == 0)
1770                         wait_event(cdev->private->wait_q,
1771                                    dev_fsm_final_state(cdev));
1772                 else
1773                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1774                                       "device 0.%x.%04x\n",
1775                                       ret, cdev->private->dev_id.ssid,
1776                                       cdev->private->dev_id.devno);
1777                 /* Give up reference obtained in ccw_device_set_online(). */
1778                 put_device(&cdev->dev);
1779                 spin_lock_irq(cdev->ccwlock);
1780         }
1781         ccw_device_set_timeout(cdev, 0);
1782         cdev->drv = NULL;
1783         cdev->private->int_class = IRQIO_CIO;
1784         spin_unlock_irq(cdev->ccwlock);
1785         __disable_cmf(cdev);
1786
1787         return 0;
1788 }
1789
1790 static void ccw_device_shutdown(struct device *dev)
1791 {
1792         struct ccw_device *cdev;
1793
1794         cdev = to_ccwdev(dev);
1795         if (cdev->drv && cdev->drv->shutdown)
1796                 cdev->drv->shutdown(cdev);
1797         __disable_cmf(cdev);
1798 }
1799
1800 static int ccw_device_pm_prepare(struct device *dev)
1801 {
1802         struct ccw_device *cdev = to_ccwdev(dev);
1803
1804         if (work_pending(&cdev->private->todo_work))
1805                 return -EAGAIN;
1806         /* Fail while device is being set online/offline. */
1807         if (atomic_read(&cdev->private->onoff))
1808                 return -EAGAIN;
1809
1810         if (cdev->online && cdev->drv && cdev->drv->prepare)
1811                 return cdev->drv->prepare(cdev);
1812
1813         return 0;
1814 }
1815
1816 static void ccw_device_pm_complete(struct device *dev)
1817 {
1818         struct ccw_device *cdev = to_ccwdev(dev);
1819
1820         if (cdev->online && cdev->drv && cdev->drv->complete)
1821                 cdev->drv->complete(cdev);
1822 }
1823
1824 static int ccw_device_pm_freeze(struct device *dev)
1825 {
1826         struct ccw_device *cdev = to_ccwdev(dev);
1827         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1828         int ret, cm_enabled;
1829
1830         /* Fail suspend while device is in transistional state. */
1831         if (!dev_fsm_final_state(cdev))
1832                 return -EAGAIN;
1833         if (!cdev->online)
1834                 return 0;
1835         if (cdev->drv && cdev->drv->freeze) {
1836                 ret = cdev->drv->freeze(cdev);
1837                 if (ret)
1838                         return ret;
1839         }
1840
1841         spin_lock_irq(sch->lock);
1842         cm_enabled = cdev->private->cmb != NULL;
1843         spin_unlock_irq(sch->lock);
1844         if (cm_enabled) {
1845                 /* Don't have the css write on memory. */
1846                 ret = ccw_set_cmf(cdev, 0);
1847                 if (ret)
1848                         return ret;
1849         }
1850         /* From here on, disallow device driver I/O. */
1851         spin_lock_irq(sch->lock);
1852         ret = cio_disable_subchannel(sch);
1853         spin_unlock_irq(sch->lock);
1854
1855         return ret;
1856 }
1857
1858 static int ccw_device_pm_thaw(struct device *dev)
1859 {
1860         struct ccw_device *cdev = to_ccwdev(dev);
1861         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1862         int ret, cm_enabled;
1863
1864         if (!cdev->online)
1865                 return 0;
1866
1867         spin_lock_irq(sch->lock);
1868         /* Allow device driver I/O again. */
1869         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1870         cm_enabled = cdev->private->cmb != NULL;
1871         spin_unlock_irq(sch->lock);
1872         if (ret)
1873                 return ret;
1874
1875         if (cm_enabled) {
1876                 ret = ccw_set_cmf(cdev, 1);
1877                 if (ret)
1878                         return ret;
1879         }
1880
1881         if (cdev->drv && cdev->drv->thaw)
1882                 ret = cdev->drv->thaw(cdev);
1883
1884         return ret;
1885 }
1886
1887 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1888 {
1889         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1890
1891         spin_lock_irq(sch->lock);
1892         if (cio_is_console(sch->schid)) {
1893                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1894                 goto out_unlock;
1895         }
1896         /*
1897          * While we were sleeping, devices may have gone or become
1898          * available again. Kick re-detection.
1899          */
1900         cdev->private->flags.resuming = 1;
1901         cdev->private->path_new_mask = LPM_ANYPATH;
1902         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1903         spin_unlock_irq(sch->lock);
1904         css_wait_for_slow_path();
1905
1906         /* cdev may have been moved to a different subchannel. */
1907         sch = to_subchannel(cdev->dev.parent);
1908         spin_lock_irq(sch->lock);
1909         if (cdev->private->state != DEV_STATE_ONLINE &&
1910             cdev->private->state != DEV_STATE_OFFLINE)
1911                 goto out_unlock;
1912
1913         ccw_device_recognition(cdev);
1914         spin_unlock_irq(sch->lock);
1915         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1916                    cdev->private->state == DEV_STATE_DISCONNECTED);
1917         spin_lock_irq(sch->lock);
1918
1919 out_unlock:
1920         cdev->private->flags.resuming = 0;
1921         spin_unlock_irq(sch->lock);
1922 }
1923
1924 static int resume_handle_boxed(struct ccw_device *cdev)
1925 {
1926         cdev->private->state = DEV_STATE_BOXED;
1927         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1928                 return 0;
1929         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1930         return -ENODEV;
1931 }
1932
1933 static int resume_handle_disc(struct ccw_device *cdev)
1934 {
1935         cdev->private->state = DEV_STATE_DISCONNECTED;
1936         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1937                 return 0;
1938         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1939         return -ENODEV;
1940 }
1941
1942 static int ccw_device_pm_restore(struct device *dev)
1943 {
1944         struct ccw_device *cdev = to_ccwdev(dev);
1945         struct subchannel *sch;
1946         int ret = 0;
1947
1948         __ccw_device_pm_restore(cdev);
1949         sch = to_subchannel(cdev->dev.parent);
1950         spin_lock_irq(sch->lock);
1951         if (cio_is_console(sch->schid))
1952                 goto out_restore;
1953
1954         /* check recognition results */
1955         switch (cdev->private->state) {
1956         case DEV_STATE_OFFLINE:
1957         case DEV_STATE_ONLINE:
1958                 cdev->private->flags.donotify = 0;
1959                 break;
1960         case DEV_STATE_BOXED:
1961                 ret = resume_handle_boxed(cdev);
1962                 if (ret)
1963                         goto out_unlock;
1964                 goto out_restore;
1965         default:
1966                 ret = resume_handle_disc(cdev);
1967                 if (ret)
1968                         goto out_unlock;
1969                 goto out_restore;
1970         }
1971         /* check if the device type has changed */
1972         if (!ccw_device_test_sense_data(cdev)) {
1973                 ccw_device_update_sense_data(cdev);
1974                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1975                 ret = -ENODEV;
1976                 goto out_unlock;
1977         }
1978         if (!cdev->online)
1979                 goto out_unlock;
1980
1981         if (ccw_device_online(cdev)) {
1982                 ret = resume_handle_disc(cdev);
1983                 if (ret)
1984                         goto out_unlock;
1985                 goto out_restore;
1986         }
1987         spin_unlock_irq(sch->lock);
1988         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1989         spin_lock_irq(sch->lock);
1990
1991         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1992                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1993                 ret = -ENODEV;
1994                 goto out_unlock;
1995         }
1996
1997         /* reenable cmf, if needed */
1998         if (cdev->private->cmb) {
1999                 spin_unlock_irq(sch->lock);
2000                 ret = ccw_set_cmf(cdev, 1);
2001                 spin_lock_irq(sch->lock);
2002                 if (ret) {
2003                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2004                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
2005                                       cdev->private->dev_id.devno, ret);
2006                         ret = 0;
2007                 }
2008         }
2009
2010 out_restore:
2011         spin_unlock_irq(sch->lock);
2012         if (cdev->online && cdev->drv && cdev->drv->restore)
2013                 ret = cdev->drv->restore(cdev);
2014         return ret;
2015
2016 out_unlock:
2017         spin_unlock_irq(sch->lock);
2018         return ret;
2019 }
2020
2021 static const struct dev_pm_ops ccw_pm_ops = {
2022         .prepare = ccw_device_pm_prepare,
2023         .complete = ccw_device_pm_complete,
2024         .freeze = ccw_device_pm_freeze,
2025         .thaw = ccw_device_pm_thaw,
2026         .restore = ccw_device_pm_restore,
2027 };
2028
2029 static struct bus_type ccw_bus_type = {
2030         .name   = "ccw",
2031         .match  = ccw_bus_match,
2032         .uevent = ccw_uevent,
2033         .probe  = ccw_device_probe,
2034         .remove = ccw_device_remove,
2035         .shutdown = ccw_device_shutdown,
2036         .pm = &ccw_pm_ops,
2037 };
2038
2039 /**
2040  * ccw_driver_register() - register a ccw driver
2041  * @cdriver: driver to be registered
2042  *
2043  * This function is mainly a wrapper around driver_register().
2044  * Returns:
2045  *   %0 on success and a negative error value on failure.
2046  */
2047 int ccw_driver_register(struct ccw_driver *cdriver)
2048 {
2049         struct device_driver *drv = &cdriver->driver;
2050
2051         drv->bus = &ccw_bus_type;
2052
2053         return driver_register(drv);
2054 }
2055
2056 /**
2057  * ccw_driver_unregister() - deregister a ccw driver
2058  * @cdriver: driver to be deregistered
2059  *
2060  * This function is mainly a wrapper around driver_unregister().
2061  */
2062 void ccw_driver_unregister(struct ccw_driver *cdriver)
2063 {
2064         driver_unregister(&cdriver->driver);
2065 }
2066
2067 static void ccw_device_todo(struct work_struct *work)
2068 {
2069         struct ccw_device_private *priv;
2070         struct ccw_device *cdev;
2071         struct subchannel *sch;
2072         enum cdev_todo todo;
2073
2074         priv = container_of(work, struct ccw_device_private, todo_work);
2075         cdev = priv->cdev;
2076         sch = to_subchannel(cdev->dev.parent);
2077         /* Find out todo. */
2078         spin_lock_irq(cdev->ccwlock);
2079         todo = priv->todo;
2080         priv->todo = CDEV_TODO_NOTHING;
2081         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2082                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2083         spin_unlock_irq(cdev->ccwlock);
2084         /* Perform todo. */
2085         switch (todo) {
2086         case CDEV_TODO_ENABLE_CMF:
2087                 cmf_reenable(cdev);
2088                 break;
2089         case CDEV_TODO_REBIND:
2090                 ccw_device_do_unbind_bind(cdev);
2091                 break;
2092         case CDEV_TODO_REGISTER:
2093                 io_subchannel_register(cdev);
2094                 break;
2095         case CDEV_TODO_UNREG_EVAL:
2096                 if (!sch_is_pseudo_sch(sch))
2097                         css_schedule_eval(sch->schid);
2098                 /* fall-through */
2099         case CDEV_TODO_UNREG:
2100                 if (sch_is_pseudo_sch(sch))
2101                         ccw_device_unregister(cdev);
2102                 else
2103                         ccw_device_call_sch_unregister(cdev);
2104                 break;
2105         default:
2106                 break;
2107         }
2108         /* Release workqueue ref. */
2109         put_device(&cdev->dev);
2110 }
2111
2112 /**
2113  * ccw_device_sched_todo - schedule ccw device operation
2114  * @cdev: ccw device
2115  * @todo: todo
2116  *
2117  * Schedule the operation identified by @todo to be performed on the slow path
2118  * workqueue. Do nothing if another operation with higher priority is already
2119  * scheduled. Needs to be called with ccwdev lock held.
2120  */
2121 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2122 {
2123         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2124                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2125                       todo);
2126         if (cdev->private->todo >= todo)
2127                 return;
2128         cdev->private->todo = todo;
2129         /* Get workqueue ref. */
2130         if (!get_device(&cdev->dev))
2131                 return;
2132         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2133                 /* Already queued, release workqueue ref. */
2134                 put_device(&cdev->dev);
2135         }
2136 }
2137
2138 /**
2139  * ccw_device_siosl() - initiate logging
2140  * @cdev: ccw device
2141  *
2142  * This function is used to invoke model-dependent logging within the channel
2143  * subsystem.
2144  */
2145 int ccw_device_siosl(struct ccw_device *cdev)
2146 {
2147         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2148
2149         return chsc_siosl(sch->schid);
2150 }
2151 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2152
2153 MODULE_LICENSE("GPL");
2154 EXPORT_SYMBOL(ccw_device_set_online);
2155 EXPORT_SYMBOL(ccw_device_set_offline);
2156 EXPORT_SYMBOL(ccw_driver_register);
2157 EXPORT_SYMBOL(ccw_driver_unregister);
2158 EXPORT_SYMBOL(get_ccwdev_by_busid);