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/timer.h>
  23 #include <linux/kernel_stat.h>
  24
  25 #include <asm/ccwdev.h>
  26 #include <asm/cio.h>
  27 #include <asm/param.h>          /* HZ */
  28 #include <asm/cmb.h>
  29 #include <asm/isc.h>
  30
  31 #include "chp.h"
  32 #include "cio.h"
  33 #include "cio_debug.h"
  34 #include "css.h"
  35 #include "device.h"
  36 #include "ioasm.h"
  37 #include "io_sch.h"
  38 #include "blacklist.h"
  39 #include "chsc.h"
  40
  41 static struct timer_list recovery_timer;
  42 static DEFINE_SPINLOCK(recovery_lock);
  43 static int recovery_phase;
  44 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  45
  46 /******************* bus type handling ***********************/
  47
  48 /* The Linux driver model distinguishes between a bus type and
  49  * the bus itself. Of course we only have one channel
  50  * subsystem driver and one channel system per machine, but
  51  * we still use the abstraction. T.R. says it's a good idea. */
  52 static int
  53 ccw_bus_match (struct device * dev, struct device_driver * drv)
  54 {
  55         struct ccw_device *cdev = to_ccwdev(dev);
  56         struct ccw_driver *cdrv = to_ccwdrv(drv);
  57         const struct ccw_device_id *ids = cdrv->ids, *found;
  58
  59         if (!ids)
  60                 return 0;
  61
  62         found = ccw_device_id_match(ids, &cdev->id);
  63         if (!found)
  64                 return 0;
  65
  66         cdev->id.driver_info = found->driver_info;
  67
  68         return 1;
  69 }
  70
  71 /* Store modalias string delimited by prefix/suffix string into buffer with
  72  * specified size. Return length of resulting string (excluding trailing '\0')
  73  * even if string doesn't fit buffer (snprintf semantics). */
  74 static int snprint_alias(char *buf, size_t size,
  75                          struct ccw_device_id *id, const char *suffix)
  76 {
  77         int len;
  78
  79         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  80         if (len > size)
  81                 return len;
  82         buf += len;
  83         size -= len;
  84
  85         if (id->dev_type != 0)
  86                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  87                                 id->dev_model, suffix);
  88         else
  89                 len += snprintf(buf, size, "dtdm%s", suffix);
  90
  91         return len;
  92 }
  93
  94 /* Set up environment variables for ccw device uevent. Return 0 on success,
  95  * non-zero otherwise. */
  96 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  97 {
  98         struct ccw_device *cdev = to_ccwdev(dev);
  99         struct ccw_device_id *id = &(cdev->id);
 100         int ret;
 101         char modalias_buf[30];
 102
 103         /* CU_TYPE= */
 104         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 105         if (ret)
 106                 return ret;
 107
 108         /* CU_MODEL= */
 109         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 110         if (ret)
 111                 return ret;
 112
 113         /* The next two can be zero, that's ok for us */
 114         /* DEV_TYPE= */
 115         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 116         if (ret)
 117                 return ret;
 118
 119         /* DEV_MODEL= */
 120         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 121         if (ret)
 122                 return ret;
 123
 124         /* MODALIAS=  */
 125         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 126         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 127         return ret;
 128 }
 129
 130 static struct bus_type ccw_bus_type;
 131
 132 static void io_subchannel_irq(struct subchannel *);
 133 static int io_subchannel_probe(struct subchannel *);
 134 static int io_subchannel_remove(struct subchannel *);
 135 static void io_subchannel_shutdown(struct subchannel *);
 136 static int io_subchannel_sch_event(struct subchannel *, int);
 137 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 138                                    int);
 139 static void recovery_func(unsigned long data);
 140 wait_queue_head_t ccw_device_init_wq;
 141 atomic_t ccw_device_init_count;
 142
 143 static struct css_device_id io_subchannel_ids[] = {
 144         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 145         { /* end of list */ },
 146 };
 147 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 148
 149 static int io_subchannel_prepare(struct subchannel *sch)
 150 {
 151         struct ccw_device *cdev;
 152         /*
 153          * Don't allow suspend while a ccw device registration
 154          * is still outstanding.
 155          */
 156         cdev = sch_get_cdev(sch);
 157         if (cdev && !device_is_registered(&cdev->dev))
 158                 return -EAGAIN;
 159         return 0;
 160 }
 161
 162 static int io_subchannel_settle(void)
 163 {
 164         int ret;
 165
 166         ret = wait_event_interruptible(ccw_device_init_wq,
 167                                 atomic_read(&ccw_device_init_count) == 0);
 168         if (ret)
 169                 return -EINTR;
 170         flush_workqueue(cio_work_q);
 171         return 0;
 172 }
 173
 174 static struct css_driver io_subchannel_driver = {
 175         .drv = {
 176                 .owner = THIS_MODULE,
 177                 .name = "io_subchannel",
 178         },
 179         .subchannel_type = io_subchannel_ids,
 180         .irq = io_subchannel_irq,
 181         .sch_event = io_subchannel_sch_event,
 182         .chp_event = io_subchannel_chp_event,
 183         .probe = io_subchannel_probe,
 184         .remove = io_subchannel_remove,
 185         .shutdown = io_subchannel_shutdown,
 186         .prepare = io_subchannel_prepare,
 187         .settle = io_subchannel_settle,
 188 };
 189
 190 int __init io_subchannel_init(void)
 191 {
 192         int ret;
 193
 194         init_waitqueue_head(&ccw_device_init_wq);
 195         atomic_set(&ccw_device_init_count, 0);
 196         setup_timer(&recovery_timer, recovery_func, 0);
 197
 198         ret = bus_register(&ccw_bus_type);
 199         if (ret)
 200                 return ret;
 201         ret = css_driver_register(&io_subchannel_driver);
 202         if (ret)
 203                 bus_unregister(&ccw_bus_type);
 204
 205         return ret;
 206 }
 207
 208
 209 /************************ device handling **************************/
 210
 211 /*
 212  * A ccw_device has some interfaces in sysfs in addition to the
 213  * standard ones.
 214  * The following entries are designed to export the information which
 215  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 216  * are obvious, so they don't have an entry :)
 217  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 218  */
 219 static ssize_t
 220 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 221 {
 222         struct subchannel *sch = to_subchannel(dev);
 223         struct chsc_ssd_info *ssd = &sch->ssd_info;
 224         ssize_t ret = 0;
 225         int chp;
 226         int mask;
 227
 228         for (chp = 0; chp < 8; chp++) {
 229                 mask = 0x80 >> chp;
 230                 if (ssd->path_mask & mask)
 231                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 232                 else
 233                         ret += sprintf(buf + ret, "00 ");
 234         }
 235         ret += sprintf (buf+ret, "\n");
 236         return min((ssize_t)PAGE_SIZE, ret);
 237 }
 238
 239 static ssize_t
 240 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 241 {
 242         struct subchannel *sch = to_subchannel(dev);
 243         struct pmcw *pmcw = &sch->schib.pmcw;
 244
 245         return sprintf (buf, "%02x %02x %02x\n",
 246                         pmcw->pim, pmcw->pam, pmcw->pom);
 247 }
 248
 249 static ssize_t
 250 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 251 {
 252         struct ccw_device *cdev = to_ccwdev(dev);
 253         struct ccw_device_id *id = &(cdev->id);
 254
 255         if (id->dev_type != 0)
 256                 return sprintf(buf, "%04x/%02x\n",
 257                                 id->dev_type, id->dev_model);
 258         else
 259                 return sprintf(buf, "n/a\n");
 260 }
 261
 262 static ssize_t
 263 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 264 {
 265         struct ccw_device *cdev = to_ccwdev(dev);
 266         struct ccw_device_id *id = &(cdev->id);
 267
 268         return sprintf(buf, "%04x/%02x\n",
 269                        id->cu_type, id->cu_model);
 270 }
 271
 272 static ssize_t
 273 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 274 {
 275         struct ccw_device *cdev = to_ccwdev(dev);
 276         struct ccw_device_id *id = &(cdev->id);
 277         int len;
 278
 279         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 280
 281         return len > PAGE_SIZE ? PAGE_SIZE : len;
 282 }
 283
 284 static ssize_t
 285 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 286 {
 287         struct ccw_device *cdev = to_ccwdev(dev);
 288
 289         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 290 }
 291
 292 int ccw_device_is_orphan(struct ccw_device *cdev)
 293 {
 294         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 295 }
 296
 297 static void ccw_device_unregister(struct ccw_device *cdev)
 298 {
 299         if (device_is_registered(&cdev->dev)) {
 300                 /* Undo device_add(). */
 301                 device_del(&cdev->dev);
 302         }
 303         if (cdev->private->flags.initialized) {
 304                 cdev->private->flags.initialized = 0;
 305                 /* Release reference from device_initialize(). */
 306                 put_device(&cdev->dev);
 307         }
 308 }
 309
 310 static void io_subchannel_quiesce(struct subchannel *);
 311
 312 /**
 313  * ccw_device_set_offline() - disable a ccw device for I/O
 314  * @cdev: target ccw device
 315  *
 316  * This function calls the driver's set_offline() function for @cdev, if
 317  * given, and then disables @cdev.
 318  * Returns:
 319  *   %0 on success and a negative error value on failure.
 320  * Context:
 321  *  enabled, ccw device lock not held
 322  */
 323 int ccw_device_set_offline(struct ccw_device *cdev)
 324 {
 325         struct subchannel *sch;
 326         int ret, state;
 327
 328         if (!cdev)
 329                 return -ENODEV;
 330         if (!cdev->online || !cdev->drv)
 331                 return -EINVAL;
 332
 333         if (cdev->drv->set_offline) {
 334                 ret = cdev->drv->set_offline(cdev);
 335                 if (ret != 0)
 336                         return ret;
 337         }
 338         cdev->online = 0;
 339         spin_lock_irq(cdev->ccwlock);
 340         sch = to_subchannel(cdev->dev.parent);
 341         /* Wait until a final state or DISCONNECTED is reached */
 342         while (!dev_fsm_final_state(cdev) &&
 343                cdev->private->state != DEV_STATE_DISCONNECTED) {
 344                 spin_unlock_irq(cdev->ccwlock);
 345                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 346                            cdev->private->state == DEV_STATE_DISCONNECTED));
 347                 spin_lock_irq(cdev->ccwlock);
 348         }
 349         do {
 350                 ret = ccw_device_offline(cdev);
 351                 if (!ret)
 352                         break;
 353                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 354                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 355                               cdev->private->dev_id.devno);
 356                 if (ret != -EBUSY)
 357                         goto error;
 358                 state = cdev->private->state;
 359                 spin_unlock_irq(cdev->ccwlock);
 360                 io_subchannel_quiesce(sch);
 361                 spin_lock_irq(cdev->ccwlock);
 362                 cdev->private->state = state;
 363         } while (ret == -EBUSY);
 364         spin_unlock_irq(cdev->ccwlock);
 365         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 366                    cdev->private->state == DEV_STATE_DISCONNECTED));
 367         /* Inform the user if set offline failed. */
 368         if (cdev->private->state == DEV_STATE_BOXED) {
 369                 pr_warning("%s: The device entered boxed state while "
 370                            "being set offline\n", dev_name(&cdev->dev));
 371         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 372                 pr_warning("%s: The device stopped operating while "
 373                            "being set offline\n", dev_name(&cdev->dev));
 374         }
 375         /* Give up reference from ccw_device_set_online(). */
 376         put_device(&cdev->dev);
 377         return 0;
 378
 379 error:
 380         cdev->private->state = DEV_STATE_OFFLINE;
 381         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 382         spin_unlock_irq(cdev->ccwlock);
 383         /* Give up reference from ccw_device_set_online(). */
 384         put_device(&cdev->dev);
 385         return -ENODEV;
 386 }
 387
 388 /**
 389  * ccw_device_set_online() - enable a ccw device for I/O
 390  * @cdev: target ccw device
 391  *
 392  * This function first enables @cdev and then calls the driver's set_online()
 393  * function for @cdev, if given. If set_online() returns an error, @cdev is
 394  * disabled again.
 395  * Returns:
 396  *   %0 on success and a negative error value on failure.
 397  * Context:
 398  *  enabled, ccw device lock not held
 399  */
 400 int ccw_device_set_online(struct ccw_device *cdev)
 401 {
 402         int ret;
 403         int ret2;
 404
 405         if (!cdev)
 406                 return -ENODEV;
 407         if (cdev->online || !cdev->drv)
 408                 return -EINVAL;
 409         /* Hold on to an extra reference while device is online. */
 410         if (!get_device(&cdev->dev))
 411                 return -ENODEV;
 412
 413         spin_lock_irq(cdev->ccwlock);
 414         ret = ccw_device_online(cdev);
 415         spin_unlock_irq(cdev->ccwlock);
 416         if (ret == 0)
 417                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 418         else {
 419                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 420                               "device 0.%x.%04x\n",
 421                               ret, cdev->private->dev_id.ssid,
 422                               cdev->private->dev_id.devno);
 423                 /* Give up online reference since onlining failed. */
 424                 put_device(&cdev->dev);
 425                 return ret;
 426         }
 427         spin_lock_irq(cdev->ccwlock);
 428         /* Check if online processing was successful */
 429         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 430             (cdev->private->state != DEV_STATE_W4SENSE)) {
 431                 spin_unlock_irq(cdev->ccwlock);
 432                 /* Inform the user that set online failed. */
 433                 if (cdev->private->state == DEV_STATE_BOXED) {
 434                         pr_warning("%s: Setting the device online failed "
 435                                    "because it is boxed\n",
 436                                    dev_name(&cdev->dev));
 437                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 438                         pr_warning("%s: Setting the device online failed "
 439                                    "because it is not operational\n",
 440                                    dev_name(&cdev->dev));
 441                 }
 442                 /* Give up online reference since onlining failed. */
 443                 put_device(&cdev->dev);
 444                 return -ENODEV;
 445         }
 446         spin_unlock_irq(cdev->ccwlock);
 447         if (cdev->drv->set_online)
 448                 ret = cdev->drv->set_online(cdev);
 449         if (ret)
 450                 goto rollback;
 451         cdev->online = 1;
 452         return 0;
 453
 454 rollback:
 455         spin_lock_irq(cdev->ccwlock);
 456         /* Wait until a final state or DISCONNECTED is reached */
 457         while (!dev_fsm_final_state(cdev) &&
 458                cdev->private->state != DEV_STATE_DISCONNECTED) {
 459                 spin_unlock_irq(cdev->ccwlock);
 460                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 461                            cdev->private->state == DEV_STATE_DISCONNECTED));
 462                 spin_lock_irq(cdev->ccwlock);
 463         }
 464         ret2 = ccw_device_offline(cdev);
 465         if (ret2)
 466                 goto error;
 467         spin_unlock_irq(cdev->ccwlock);
 468         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 469                    cdev->private->state == DEV_STATE_DISCONNECTED));
 470         /* Give up online reference since onlining failed. */
 471         put_device(&cdev->dev);
 472         return ret;
 473
 474 error:
 475         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 476                       "device 0.%x.%04x\n",
 477                       ret2, cdev->private->dev_id.ssid,
 478                       cdev->private->dev_id.devno);
 479         cdev->private->state = DEV_STATE_OFFLINE;
 480         spin_unlock_irq(cdev->ccwlock);
 481         /* Give up online reference since onlining failed. */
 482         put_device(&cdev->dev);
 483         return ret;
 484 }
 485
 486 static int online_store_handle_offline(struct ccw_device *cdev)
 487 {
 488         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 489                 spin_lock_irq(cdev->ccwlock);
 490                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 491                 spin_unlock_irq(cdev->ccwlock);
 492                 return 0;
 493         }
 494         if (cdev->drv && cdev->drv->set_offline)
 495                 return ccw_device_set_offline(cdev);
 496         return -EINVAL;
 497 }
 498
 499 static int online_store_recog_and_online(struct ccw_device *cdev)
 500 {
 501         /* Do device recognition, if needed. */
 502         if (cdev->private->state == DEV_STATE_BOXED) {
 503                 spin_lock_irq(cdev->ccwlock);
 504                 ccw_device_recognition(cdev);
 505                 spin_unlock_irq(cdev->ccwlock);
 506                 wait_event(cdev->private->wait_q,
 507                            cdev->private->flags.recog_done);
 508                 if (cdev->private->state != DEV_STATE_OFFLINE)
 509                         /* recognition failed */
 510                         return -EAGAIN;
 511         }
 512         if (cdev->drv && cdev->drv->set_online)
 513                 return ccw_device_set_online(cdev);
 514         return -EINVAL;
 515 }
 516
 517 static int online_store_handle_online(struct ccw_device *cdev, int force)
 518 {
 519         int ret;
 520
 521         ret = online_store_recog_and_online(cdev);
 522         if (ret && !force)
 523                 return ret;
 524         if (force && cdev->private->state == DEV_STATE_BOXED) {
 525                 ret = ccw_device_stlck(cdev);
 526                 if (ret)
 527                         return ret;
 528                 if (cdev->id.cu_type == 0)
 529                         cdev->private->state = DEV_STATE_NOT_OPER;
 530                 ret = online_store_recog_and_online(cdev);
 531                 if (ret)
 532                         return ret;
 533         }
 534         return 0;
 535 }
 536
 537 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 538                              const char *buf, size_t count)
 539 {
 540         struct ccw_device *cdev = to_ccwdev(dev);
 541         int force, ret;
 542         unsigned long i;
 543
 544         /* Prevent conflict between multiple on-/offline processing requests. */
 545         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 546                 return -EAGAIN;
 547         /* Prevent conflict between internal I/Os and on-/offline processing. */
 548         if (!dev_fsm_final_state(cdev) &&
 549             cdev->private->state != DEV_STATE_DISCONNECTED) {
 550                 ret = -EAGAIN;
 551                 goto out_onoff;
 552         }
 553         /* Prevent conflict between pending work and on-/offline processing.*/
 554         if (work_pending(&cdev->private->todo_work)) {
 555                 ret = -EAGAIN;
 556                 goto out_onoff;
 557         }
 558
 559         if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
 560                 ret = -EINVAL;
 561                 goto out_onoff;
 562         }
 563         if (!strncmp(buf, "force\n", count)) {
 564                 force = 1;
 565                 i = 1;
 566                 ret = 0;
 567         } else {
 568                 force = 0;
 569                 ret = strict_strtoul(buf, 16, &i);
 570         }
 571         if (ret)
 572                 goto out;
 573         switch (i) {
 574         case 0:
 575                 ret = online_store_handle_offline(cdev);
 576                 break;
 577         case 1:
 578                 ret = online_store_handle_online(cdev, force);
 579                 break;
 580         default:
 581                 ret = -EINVAL;
 582         }
 583 out:
 584         if (cdev->drv)
 585                 module_put(cdev->drv->driver.owner);
 586 out_onoff:
 587         atomic_set(&cdev->private->onoff, 0);
 588         return (ret < 0) ? ret : count;
 589 }
 590
 591 static ssize_t
 592 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 593 {
 594         struct ccw_device *cdev = to_ccwdev(dev);
 595         struct subchannel *sch;
 596
 597         if (ccw_device_is_orphan(cdev))
 598                 return sprintf(buf, "no device\n");
 599         switch (cdev->private->state) {
 600         case DEV_STATE_BOXED:
 601                 return sprintf(buf, "boxed\n");
 602         case DEV_STATE_DISCONNECTED:
 603         case DEV_STATE_DISCONNECTED_SENSE_ID:
 604         case DEV_STATE_NOT_OPER:
 605                 sch = to_subchannel(dev->parent);
 606                 if (!sch->lpm)
 607                         return sprintf(buf, "no path\n");
 608                 else
 609                         return sprintf(buf, "no device\n");
 610         default:
 611                 /* All other states considered fine. */
 612                 return sprintf(buf, "good\n");
 613         }
 614 }
 615
 616 static ssize_t
 617 initiate_logging(struct device *dev, struct device_attribute *attr,
 618                  const char *buf, size_t count)
 619 {
 620         struct subchannel *sch = to_subchannel(dev);
 621         int rc;
 622
 623         rc = chsc_siosl(sch->schid);
 624         if (rc < 0) {
 625                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
 626                            "errno=%d\n",
 627                            sch->schid.ssid, sch->schid.sch_no, rc);
 628                 return rc;
 629         }
 630         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 631                   sch->schid.ssid, sch->schid.sch_no);
 632         return count;
 633 }
 634
 635 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 636 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 637 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 638 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 639 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 640 static DEVICE_ATTR(online, 0644, online_show, online_store);
 641 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 642 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 643
 644 static struct attribute *io_subchannel_attrs[] = {
 645         &dev_attr_chpids.attr,
 646         &dev_attr_pimpampom.attr,
 647         &dev_attr_logging.attr,
 648         NULL,
 649 };
 650
 651 static struct attribute_group io_subchannel_attr_group = {
 652         .attrs = io_subchannel_attrs,
 653 };
 654
 655 static struct attribute * ccwdev_attrs[] = {
 656         &dev_attr_devtype.attr,
 657         &dev_attr_cutype.attr,
 658         &dev_attr_modalias.attr,
 659         &dev_attr_online.attr,
 660         &dev_attr_cmb_enable.attr,
 661         &dev_attr_availability.attr,
 662         NULL,
 663 };
 664
 665 static struct attribute_group ccwdev_attr_group = {
 666         .attrs = ccwdev_attrs,
 667 };
 668
 669 static const struct attribute_group *ccwdev_attr_groups[] = {
 670         &ccwdev_attr_group,
 671         NULL,
 672 };
 673
 674 /* this is a simple abstraction for device_register that sets the
 675  * correct bus type and adds the bus specific files */
 676 static int ccw_device_register(struct ccw_device *cdev)
 677 {
 678         struct device *dev = &cdev->dev;
 679         int ret;
 680
 681         dev->bus = &ccw_bus_type;
 682         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 683                            cdev->private->dev_id.devno);
 684         if (ret)
 685                 return ret;
 686         return device_add(dev);
 687 }
 688
 689 static int match_dev_id(struct device *dev, void *data)
 690 {
 691         struct ccw_device *cdev = to_ccwdev(dev);
 692         struct ccw_dev_id *dev_id = data;
 693
 694         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 695 }
 696
 697 /**
 698  * get_ccwdev_by_dev_id() - obtain device from a ccw device id
 699  * @dev_id: id of the device to be searched
 700  *
 701  * This function searches all devices attached to the ccw bus for a device
 702  * matching @dev_id.
 703  * Returns:
 704  *  If a device is found its reference count is increased and returned;
 705  *  else %NULL is returned.
 706  */
 707 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 708 {
 709         struct device *dev;
 710
 711         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 712
 713         return dev ? to_ccwdev(dev) : NULL;
 714 }
 715 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
 716
 717 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 718 {
 719         int ret;
 720
 721         if (device_is_registered(&cdev->dev)) {
 722                 device_release_driver(&cdev->dev);
 723                 ret = device_attach(&cdev->dev);
 724                 WARN_ON(ret == -ENODEV);
 725         }
 726 }
 727
 728 static void
 729 ccw_device_release(struct device *dev)
 730 {
 731         struct ccw_device *cdev;
 732
 733         cdev = to_ccwdev(dev);
 734         /* Release reference of parent subchannel. */
 735         put_device(cdev->dev.parent);
 736         kfree(cdev->private);
 737         kfree(cdev);
 738 }
 739
 740 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 741 {
 742         struct ccw_device *cdev;
 743
 744         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 745         if (cdev) {
 746                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 747                                         GFP_KERNEL | GFP_DMA);
 748                 if (cdev->private)
 749                         return cdev;
 750         }
 751         kfree(cdev);
 752         return ERR_PTR(-ENOMEM);
 753 }
 754
 755 static void ccw_device_todo(struct work_struct *work);
 756
 757 static int io_subchannel_initialize_dev(struct subchannel *sch,
 758                                         struct ccw_device *cdev)
 759 {
 760         cdev->private->cdev = cdev;
 761         cdev->private->int_class = IOINT_CIO;
 762         atomic_set(&cdev->private->onoff, 0);
 763         cdev->dev.parent = &sch->dev;
 764         cdev->dev.release = ccw_device_release;
 765         INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
 766         cdev->dev.groups = ccwdev_attr_groups;
 767         /* Do first half of device_register. */
 768         device_initialize(&cdev->dev);
 769         if (!get_device(&sch->dev)) {
 770                 /* Release reference from device_initialize(). */
 771                 put_device(&cdev->dev);
 772                 return -ENODEV;
 773         }
 774         cdev->private->flags.initialized = 1;
 775         return 0;
 776 }
 777
 778 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 779 {
 780         struct ccw_device *cdev;
 781         int ret;
 782
 783         cdev = io_subchannel_allocate_dev(sch);
 784         if (!IS_ERR(cdev)) {
 785                 ret = io_subchannel_initialize_dev(sch, cdev);
 786                 if (ret)
 787                         cdev = ERR_PTR(ret);
 788         }
 789         return cdev;
 790 }
 791
 792 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 793
 794 static void sch_create_and_recog_new_device(struct subchannel *sch)
 795 {
 796         struct ccw_device *cdev;
 797
 798         /* Need to allocate a new ccw device. */
 799         cdev = io_subchannel_create_ccwdev(sch);
 800         if (IS_ERR(cdev)) {
 801                 /* OK, we did everything we could... */
 802                 css_sch_device_unregister(sch);
 803                 return;
 804         }
 805         /* Start recognition for the new ccw device. */
 806         io_subchannel_recog(cdev, sch);
 807 }
 808
 809 /*
 810  * Register recognized device.
 811  */
 812 static void io_subchannel_register(struct ccw_device *cdev)
 813 {
 814         struct subchannel *sch;
 815         int ret, adjust_init_count = 1;
 816         unsigned long flags;
 817
 818         sch = to_subchannel(cdev->dev.parent);
 819         /*
 820          * Check if subchannel is still registered. It may have become
 821          * unregistered if a machine check hit us after finishing
 822          * device recognition but before the register work could be
 823          * queued.
 824          */
 825         if (!device_is_registered(&sch->dev))
 826                 goto out_err;
 827         css_update_ssd_info(sch);
 828         /*
 829          * io_subchannel_register() will also be called after device
 830          * recognition has been done for a boxed device (which will already
 831          * be registered). We need to reprobe since we may now have sense id
 832          * information.
 833          */
 834         if (device_is_registered(&cdev->dev)) {
 835                 if (!cdev->drv) {
 836                         ret = device_reprobe(&cdev->dev);
 837                         if (ret)
 838                                 /* We can't do much here. */
 839                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 840                                               " %d for 0.%x.%04x\n", ret,
 841                                               cdev->private->dev_id.ssid,
 842                                               cdev->private->dev_id.devno);
 843                 }
 844                 adjust_init_count = 0;
 845                 goto out;
 846         }
 847         /*
 848          * Now we know this subchannel will stay, we can throw
 849          * our delayed uevent.
 850          */
 851         dev_set_uevent_suppress(&sch->dev, 0);
 852         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 853         /* make it known to the system */
 854         ret = ccw_device_register(cdev);
 855         if (ret) {
 856                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 857                               cdev->private->dev_id.ssid,
 858                               cdev->private->dev_id.devno, ret);
 859                 spin_lock_irqsave(sch->lock, flags);
 860                 sch_set_cdev(sch, NULL);
 861                 spin_unlock_irqrestore(sch->lock, flags);
 862                 /* Release initial device reference. */
 863                 put_device(&cdev->dev);
 864                 goto out_err;
 865         }
 866 out:
 867         cdev->private->flags.recog_done = 1;
 868         wake_up(&cdev->private->wait_q);
 869 out_err:
 870         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 871                 wake_up(&ccw_device_init_wq);
 872 }
 873
 874 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 875 {
 876         struct subchannel *sch;
 877
 878         /* Get subchannel reference for local processing. */
 879         if (!get_device(cdev->dev.parent))
 880                 return;
 881         sch = to_subchannel(cdev->dev.parent);
 882         css_sch_device_unregister(sch);
 883         /* Release subchannel reference for local processing. */
 884         put_device(&sch->dev);
 885 }
 886
 887 /*
 888  * subchannel recognition done. Called from the state machine.
 889  */
 890 void
 891 io_subchannel_recog_done(struct ccw_device *cdev)
 892 {
 893         if (css_init_done == 0) {
 894                 cdev->private->flags.recog_done = 1;
 895                 return;
 896         }
 897         switch (cdev->private->state) {
 898         case DEV_STATE_BOXED:
 899                 /* Device did not respond in time. */
 900         case DEV_STATE_NOT_OPER:
 901                 cdev->private->flags.recog_done = 1;
 902                 /* Remove device found not operational. */
 903                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 904                 if (atomic_dec_and_test(&ccw_device_init_count))
 905                         wake_up(&ccw_device_init_wq);
 906                 break;
 907         case DEV_STATE_OFFLINE:
 908                 /*
 909                  * We can't register the device in interrupt context so
 910                  * we schedule a work item.
 911                  */
 912                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 913                 break;
 914         }
 915 }
 916
 917 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 918 {
 919         struct ccw_device_private *priv;
 920
 921         cdev->ccwlock = sch->lock;
 922
 923         /* Init private data. */
 924         priv = cdev->private;
 925         priv->dev_id.devno = sch->schib.pmcw.dev;
 926         priv->dev_id.ssid = sch->schid.ssid;
 927         priv->schid = sch->schid;
 928         priv->state = DEV_STATE_NOT_OPER;
 929         INIT_LIST_HEAD(&priv->cmb_list);
 930         init_waitqueue_head(&priv->wait_q);
 931         init_timer(&priv->timer);
 932
 933         /* Increase counter of devices currently in recognition. */
 934         atomic_inc(&ccw_device_init_count);
 935
 936         /* Start async. device sensing. */
 937         spin_lock_irq(sch->lock);
 938         sch_set_cdev(sch, cdev);
 939         ccw_device_recognition(cdev);
 940         spin_unlock_irq(sch->lock);
 941 }
 942
 943 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 944                                   struct subchannel *sch)
 945 {
 946         struct subchannel *old_sch;
 947         int rc, old_enabled = 0;
 948
 949         old_sch = to_subchannel(cdev->dev.parent);
 950         /* Obtain child reference for new parent. */
 951         if (!get_device(&sch->dev))
 952                 return -ENODEV;
 953
 954         if (!sch_is_pseudo_sch(old_sch)) {
 955                 spin_lock_irq(old_sch->lock);
 956                 old_enabled = old_sch->schib.pmcw.ena;
 957                 rc = 0;
 958                 if (old_enabled)
 959                         rc = cio_disable_subchannel(old_sch);
 960                 spin_unlock_irq(old_sch->lock);
 961                 if (rc == -EBUSY) {
 962                         /* Release child reference for new parent. */
 963                         put_device(&sch->dev);
 964                         return rc;
 965                 }
 966         }
 967
 968         mutex_lock(&sch->reg_mutex);
 969         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 970         mutex_unlock(&sch->reg_mutex);
 971         if (rc) {
 972                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 973                               cdev->private->dev_id.ssid,
 974                               cdev->private->dev_id.devno, sch->schid.ssid,
 975                               sch->schib.pmcw.dev, rc);
 976                 if (old_enabled) {
 977                         /* Try to reenable the old subchannel. */
 978                         spin_lock_irq(old_sch->lock);
 979                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 980                         spin_unlock_irq(old_sch->lock);
 981                 }
 982                 /* Release child reference for new parent. */
 983                 put_device(&sch->dev);
 984                 return rc;
 985         }
 986         /* Clean up old subchannel. */
 987         if (!sch_is_pseudo_sch(old_sch)) {
 988                 spin_lock_irq(old_sch->lock);
 989                 sch_set_cdev(old_sch, NULL);
 990                 spin_unlock_irq(old_sch->lock);
 991                 css_schedule_eval(old_sch->schid);
 992         }
 993         /* Release child reference for old parent. */
 994         put_device(&old_sch->dev);
 995         /* Initialize new subchannel. */
 996         spin_lock_irq(sch->lock);
 997         cdev->private->schid = sch->schid;
 998         cdev->ccwlock = sch->lock;
 999         if (!sch_is_pseudo_sch(sch))
1000                 sch_set_cdev(sch, cdev);
1001         spin_unlock_irq(sch->lock);
1002         if (!sch_is_pseudo_sch(sch))
1003                 css_update_ssd_info(sch);
1004         return 0;
1005 }
1006
1007 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1008 {
1009         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1010         struct channel_subsystem *css = to_css(sch->dev.parent);
1011
1012         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1013 }
1014
1015 static void io_subchannel_irq(struct subchannel *sch)
1016 {
1017         struct ccw_device *cdev;
1018
1019         cdev = sch_get_cdev(sch);
1020
1021         CIO_TRACE_EVENT(6, "IRQ");
1022         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1023         if (cdev)
1024                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1025         else
1026                 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
1027 }
1028
1029 void io_subchannel_init_config(struct subchannel *sch)
1030 {
1031         memset(&sch->config, 0, sizeof(sch->config));
1032         sch->config.csense = 1;
1033 }
1034
1035 static void io_subchannel_init_fields(struct subchannel *sch)
1036 {
1037         if (cio_is_console(sch->schid))
1038                 sch->opm = 0xff;
1039         else
1040                 sch->opm = chp_get_sch_opm(sch);
1041         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1042         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1043
1044         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1045                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1046                       sch->schib.pmcw.dev, sch->schid.ssid,
1047                       sch->schid.sch_no, sch->schib.pmcw.pim,
1048                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1049
1050         io_subchannel_init_config(sch);
1051 }
1052
1053 /*
1054  * Note: We always return 0 so that we bind to the device even on error.
1055  * This is needed so that our remove function is called on unregister.
1056  */
1057 static int io_subchannel_probe(struct subchannel *sch)
1058 {
1059         struct io_subchannel_private *io_priv;
1060         struct ccw_device *cdev;
1061         int rc;
1062
1063         if (cio_is_console(sch->schid)) {
1064                 rc = sysfs_create_group(&sch->dev.kobj,
1065                                         &io_subchannel_attr_group);
1066                 if (rc)
1067                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1068                                       "attributes for subchannel "
1069                                       "0.%x.%04x (rc=%d)\n",
1070                                       sch->schid.ssid, sch->schid.sch_no, rc);
1071                 /*
1072                  * The console subchannel already has an associated ccw_device.
1073                  * Throw the delayed uevent for the subchannel, register
1074                  * the ccw_device and exit.
1075                  */
1076                 dev_set_uevent_suppress(&sch->dev, 0);
1077                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1078                 cdev = sch_get_cdev(sch);
1079                 cdev->dev.groups = ccwdev_attr_groups;
1080                 device_initialize(&cdev->dev);
1081                 cdev->private->flags.initialized = 1;
1082                 ccw_device_register(cdev);
1083                 /*
1084                  * Check if the device is already online. If it is
1085                  * the reference count needs to be corrected since we
1086                  * didn't obtain a reference in ccw_device_set_online.
1087                  */
1088                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1089                     cdev->private->state != DEV_STATE_OFFLINE &&
1090                     cdev->private->state != DEV_STATE_BOXED)
1091                         get_device(&cdev->dev);
1092                 return 0;
1093         }
1094         io_subchannel_init_fields(sch);
1095         rc = cio_commit_config(sch);
1096         if (rc)
1097                 goto out_schedule;
1098         rc = sysfs_create_group(&sch->dev.kobj,
1099                                 &io_subchannel_attr_group);
1100         if (rc)
1101                 goto out_schedule;
1102         /* Allocate I/O subchannel private data. */
1103         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1104         if (!io_priv)
1105                 goto out_schedule;
1106
1107         set_io_private(sch, io_priv);
1108         css_schedule_eval(sch->schid);
1109         return 0;
1110
1111 out_schedule:
1112         spin_lock_irq(sch->lock);
1113         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1114         spin_unlock_irq(sch->lock);
1115         return 0;
1116 }
1117
1118 static int
1119 io_subchannel_remove (struct subchannel *sch)
1120 {
1121         struct io_subchannel_private *io_priv = to_io_private(sch);
1122         struct ccw_device *cdev;
1123
1124         cdev = sch_get_cdev(sch);
1125         if (!cdev)
1126                 goto out_free;
1127         io_subchannel_quiesce(sch);
1128         /* Set ccw device to not operational and drop reference. */
1129         spin_lock_irq(cdev->ccwlock);
1130         sch_set_cdev(sch, NULL);
1131         set_io_private(sch, NULL);
1132         cdev->private->state = DEV_STATE_NOT_OPER;
1133         spin_unlock_irq(cdev->ccwlock);
1134         ccw_device_unregister(cdev);
1135 out_free:
1136         kfree(io_priv);
1137         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1138         return 0;
1139 }
1140
1141 static void io_subchannel_verify(struct subchannel *sch)
1142 {
1143         struct ccw_device *cdev;
1144
1145         cdev = sch_get_cdev(sch);
1146         if (cdev)
1147                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1148 }
1149
1150 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1151 {
1152         struct ccw_device *cdev;
1153
1154         cdev = sch_get_cdev(sch);
1155         if (!cdev)
1156                 return;
1157         if (cio_update_schib(sch))
1158                 goto err;
1159         /* Check for I/O on path. */
1160         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1161                 goto out;
1162         if (cdev->private->state == DEV_STATE_ONLINE) {
1163                 ccw_device_kill_io(cdev);
1164                 goto out;
1165         }
1166         if (cio_clear(sch))
1167                 goto err;
1168 out:
1169         /* Trigger path verification. */
1170         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1171         return;
1172
1173 err:
1174         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1175 }
1176
1177 static int io_subchannel_chp_event(struct subchannel *sch,
1178                                    struct chp_link *link, int event)
1179 {
1180         struct ccw_device *cdev = sch_get_cdev(sch);
1181         int mask;
1182
1183         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1184         if (!mask)
1185                 return 0;
1186         switch (event) {
1187         case CHP_VARY_OFF:
1188                 sch->opm &= ~mask;
1189                 sch->lpm &= ~mask;
1190                 if (cdev)
1191                         cdev->private->path_gone_mask |= mask;
1192                 io_subchannel_terminate_path(sch, mask);
1193                 break;
1194         case CHP_VARY_ON:
1195                 sch->opm |= mask;
1196                 sch->lpm |= mask;
1197                 if (cdev)
1198                         cdev->private->path_new_mask |= mask;
1199                 io_subchannel_verify(sch);
1200                 break;
1201         case CHP_OFFLINE:
1202                 if (cio_update_schib(sch))
1203                         return -ENODEV;
1204                 if (cdev)
1205                         cdev->private->path_gone_mask |= mask;
1206                 io_subchannel_terminate_path(sch, mask);
1207                 break;
1208         case CHP_ONLINE:
1209                 if (cio_update_schib(sch))
1210                         return -ENODEV;
1211                 sch->lpm |= mask & sch->opm;
1212                 if (cdev)
1213                         cdev->private->path_new_mask |= mask;
1214                 io_subchannel_verify(sch);
1215                 break;
1216         }
1217         return 0;
1218 }
1219
1220 static void io_subchannel_quiesce(struct subchannel *sch)
1221 {
1222         struct ccw_device *cdev;
1223         int ret;
1224
1225         spin_lock_irq(sch->lock);
1226         cdev = sch_get_cdev(sch);
1227         if (cio_is_console(sch->schid))
1228                 goto out_unlock;
1229         if (!sch->schib.pmcw.ena)
1230                 goto out_unlock;
1231         ret = cio_disable_subchannel(sch);
1232         if (ret != -EBUSY)
1233                 goto out_unlock;
1234         if (cdev->handler)
1235                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1236         while (ret == -EBUSY) {
1237                 cdev->private->state = DEV_STATE_QUIESCE;
1238                 cdev->private->iretry = 255;
1239                 ret = ccw_device_cancel_halt_clear(cdev);
1240                 if (ret == -EBUSY) {
1241                         ccw_device_set_timeout(cdev, HZ/10);
1242                         spin_unlock_irq(sch->lock);
1243                         wait_event(cdev->private->wait_q,
1244                                    cdev->private->state != DEV_STATE_QUIESCE);
1245                         spin_lock_irq(sch->lock);
1246                 }
1247                 ret = cio_disable_subchannel(sch);
1248         }
1249 out_unlock:
1250         spin_unlock_irq(sch->lock);
1251 }
1252
1253 static void io_subchannel_shutdown(struct subchannel *sch)
1254 {
1255         io_subchannel_quiesce(sch);
1256 }
1257
1258 static int device_is_disconnected(struct ccw_device *cdev)
1259 {
1260         if (!cdev)
1261                 return 0;
1262         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1263                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1264 }
1265
1266 static int recovery_check(struct device *dev, void *data)
1267 {
1268         struct ccw_device *cdev = to_ccwdev(dev);
1269         int *redo = data;
1270
1271         spin_lock_irq(cdev->ccwlock);
1272         switch (cdev->private->state) {
1273         case DEV_STATE_DISCONNECTED:
1274                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1275                               cdev->private->dev_id.ssid,
1276                               cdev->private->dev_id.devno);
1277                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1278                 *redo = 1;
1279                 break;
1280         case DEV_STATE_DISCONNECTED_SENSE_ID:
1281                 *redo = 1;
1282                 break;
1283         }
1284         spin_unlock_irq(cdev->ccwlock);
1285
1286         return 0;
1287 }
1288
1289 static void recovery_work_func(struct work_struct *unused)
1290 {
1291         int redo = 0;
1292
1293         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1294         if (redo) {
1295                 spin_lock_irq(&recovery_lock);
1296                 if (!timer_pending(&recovery_timer)) {
1297                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1298                                 recovery_phase++;
1299                         mod_timer(&recovery_timer, jiffies +
1300                                   recovery_delay[recovery_phase] * HZ);
1301                 }
1302                 spin_unlock_irq(&recovery_lock);
1303         } else
1304                 CIO_MSG_EVENT(4, "recovery: end\n");
1305 }
1306
1307 static DECLARE_WORK(recovery_work, recovery_work_func);
1308
1309 static void recovery_func(unsigned long data)
1310 {
1311         /*
1312          * We can't do our recovery in softirq context and it's not
1313          * performance critical, so we schedule it.
1314          */
1315         schedule_work(&recovery_work);
1316 }
1317
1318 static void ccw_device_schedule_recovery(void)
1319 {
1320         unsigned long flags;
1321
1322         CIO_MSG_EVENT(4, "recovery: schedule\n");
1323         spin_lock_irqsave(&recovery_lock, flags);
1324         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1325                 recovery_phase = 0;
1326                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1327         }
1328         spin_unlock_irqrestore(&recovery_lock, flags);
1329 }
1330
1331 static int purge_fn(struct device *dev, void *data)
1332 {
1333         struct ccw_device *cdev = to_ccwdev(dev);
1334         struct ccw_dev_id *id = &cdev->private->dev_id;
1335
1336         spin_lock_irq(cdev->ccwlock);
1337         if (is_blacklisted(id->ssid, id->devno) &&
1338             (cdev->private->state == DEV_STATE_OFFLINE) &&
1339             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1340                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1341                               id->devno);
1342                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1343                 atomic_set(&cdev->private->onoff, 0);
1344         }
1345         spin_unlock_irq(cdev->ccwlock);
1346         /* Abort loop in case of pending signal. */
1347         if (signal_pending(current))
1348                 return -EINTR;
1349
1350         return 0;
1351 }
1352
1353 /**
1354  * ccw_purge_blacklisted - purge unused, blacklisted devices
1355  *
1356  * Unregister all ccw devices that are offline and on the blacklist.
1357  */
1358 int ccw_purge_blacklisted(void)
1359 {
1360         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1361         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1362         return 0;
1363 }
1364
1365 void ccw_device_set_disconnected(struct ccw_device *cdev)
1366 {
1367         if (!cdev)
1368                 return;
1369         ccw_device_set_timeout(cdev, 0);
1370         cdev->private->flags.fake_irb = 0;
1371         cdev->private->state = DEV_STATE_DISCONNECTED;
1372         if (cdev->online)
1373                 ccw_device_schedule_recovery();
1374 }
1375
1376 void ccw_device_set_notoper(struct ccw_device *cdev)
1377 {
1378         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1379
1380         CIO_TRACE_EVENT(2, "notoper");
1381         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1382         ccw_device_set_timeout(cdev, 0);
1383         cio_disable_subchannel(sch);
1384         cdev->private->state = DEV_STATE_NOT_OPER;
1385 }
1386
1387 enum io_sch_action {
1388         IO_SCH_UNREG,
1389         IO_SCH_ORPH_UNREG,
1390         IO_SCH_ATTACH,
1391         IO_SCH_UNREG_ATTACH,
1392         IO_SCH_ORPH_ATTACH,
1393         IO_SCH_REPROBE,
1394         IO_SCH_VERIFY,
1395         IO_SCH_DISC,
1396         IO_SCH_NOP,
1397 };
1398
1399 static enum io_sch_action sch_get_action(struct subchannel *sch)
1400 {
1401         struct ccw_device *cdev;
1402
1403         cdev = sch_get_cdev(sch);
1404         if (cio_update_schib(sch)) {
1405                 /* Not operational. */
1406                 if (!cdev)
1407                         return IO_SCH_UNREG;
1408                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1409                         return IO_SCH_UNREG;
1410                 return IO_SCH_ORPH_UNREG;
1411         }
1412         /* Operational. */
1413         if (!cdev)
1414                 return IO_SCH_ATTACH;
1415         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1416                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1417                         return IO_SCH_UNREG_ATTACH;
1418                 return IO_SCH_ORPH_ATTACH;
1419         }
1420         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1421                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1422                         return IO_SCH_UNREG;
1423                 return IO_SCH_DISC;
1424         }
1425         if (device_is_disconnected(cdev))
1426                 return IO_SCH_REPROBE;
1427         if (cdev->online)
1428                 return IO_SCH_VERIFY;
1429         if (cdev->private->state == DEV_STATE_NOT_OPER)
1430                 return IO_SCH_UNREG_ATTACH;
1431         return IO_SCH_NOP;
1432 }
1433
1434 /**
1435  * io_subchannel_sch_event - process subchannel event
1436  * @sch: subchannel
1437  * @process: non-zero if function is called in process context
1438  *
1439  * An unspecified event occurred for this subchannel. Adjust data according
1440  * to the current operational state of the subchannel and device. Return
1441  * zero when the event has been handled sufficiently or -EAGAIN when this
1442  * function should be called again in process context.
1443  */
1444 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1445 {
1446         unsigned long flags;
1447         struct ccw_device *cdev;
1448         struct ccw_dev_id dev_id;
1449         enum io_sch_action action;
1450         int rc = -EAGAIN;
1451
1452         spin_lock_irqsave(sch->lock, flags);
1453         if (!device_is_registered(&sch->dev))
1454                 goto out_unlock;
1455         if (work_pending(&sch->todo_work))
1456                 goto out_unlock;
1457         cdev = sch_get_cdev(sch);
1458         if (cdev && work_pending(&cdev->private->todo_work))
1459                 goto out_unlock;
1460         action = sch_get_action(sch);
1461         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1462                       sch->schid.ssid, sch->schid.sch_no, process,
1463                       action);
1464         /* Perform immediate actions while holding the lock. */
1465         switch (action) {
1466         case IO_SCH_REPROBE:
1467                 /* Trigger device recognition. */
1468                 ccw_device_trigger_reprobe(cdev);
1469                 rc = 0;
1470                 goto out_unlock;
1471         case IO_SCH_VERIFY:
1472                 if (cdev->private->flags.resuming == 1) {
1473                         if (cio_enable_subchannel(sch, (u32)(addr_t)sch)) {
1474                                 ccw_device_set_notoper(cdev);
1475                                 break;
1476                         }
1477                 }
1478                 /* Trigger path verification. */
1479                 io_subchannel_verify(sch);
1480                 rc = 0;
1481                 goto out_unlock;
1482         case IO_SCH_DISC:
1483                 ccw_device_set_disconnected(cdev);
1484                 rc = 0;
1485                 goto out_unlock;
1486         case IO_SCH_ORPH_UNREG:
1487         case IO_SCH_ORPH_ATTACH:
1488                 ccw_device_set_disconnected(cdev);
1489                 break;
1490         case IO_SCH_UNREG_ATTACH:
1491         case IO_SCH_UNREG:
1492                 if (!cdev)
1493                         break;
1494                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1495                         /*
1496                          * Note: delayed work triggered by this event
1497                          * and repeated calls to sch_event are synchronized
1498                          * by the above check for work_pending(cdev).
1499                          */
1500                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1501                 } else
1502                         ccw_device_set_notoper(cdev);
1503                 break;
1504         case IO_SCH_NOP:
1505                 rc = 0;
1506                 goto out_unlock;
1507         default:
1508                 break;
1509         }
1510         spin_unlock_irqrestore(sch->lock, flags);
1511         /* All other actions require process context. */
1512         if (!process)
1513                 goto out;
1514         /* Handle attached ccw device. */
1515         switch (action) {
1516         case IO_SCH_ORPH_UNREG:
1517         case IO_SCH_ORPH_ATTACH:
1518                 /* Move ccw device to orphanage. */
1519                 rc = ccw_device_move_to_orph(cdev);
1520                 if (rc)
1521                         goto out;
1522                 break;
1523         case IO_SCH_UNREG_ATTACH:
1524                 spin_lock_irqsave(sch->lock, flags);
1525                 if (cdev->private->flags.resuming) {
1526                         /* Device will be handled later. */
1527                         rc = 0;
1528                         goto out_unlock;
1529                 }
1530                 sch_set_cdev(sch, NULL);
1531                 spin_unlock_irqrestore(sch->lock, flags);
1532                 /* Unregister ccw device. */
1533                 ccw_device_unregister(cdev);
1534                 break;
1535         default:
1536                 break;
1537         }
1538         /* Handle subchannel. */
1539         switch (action) {
1540         case IO_SCH_ORPH_UNREG:
1541         case IO_SCH_UNREG:
1542                 if (!cdev || !cdev->private->flags.resuming)
1543                         css_sch_device_unregister(sch);
1544                 break;
1545         case IO_SCH_ORPH_ATTACH:
1546         case IO_SCH_UNREG_ATTACH:
1547         case IO_SCH_ATTACH:
1548                 dev_id.ssid = sch->schid.ssid;
1549                 dev_id.devno = sch->schib.pmcw.dev;
1550                 cdev = get_ccwdev_by_dev_id(&dev_id);
1551                 if (!cdev) {
1552                         sch_create_and_recog_new_device(sch);
1553                         break;
1554                 }
1555                 rc = ccw_device_move_to_sch(cdev, sch);
1556                 if (rc) {
1557                         /* Release reference from get_ccwdev_by_dev_id() */
1558                         put_device(&cdev->dev);
1559                         goto out;
1560                 }
1561                 spin_lock_irqsave(sch->lock, flags);
1562                 ccw_device_trigger_reprobe(cdev);
1563                 spin_unlock_irqrestore(sch->lock, flags);
1564                 /* Release reference from get_ccwdev_by_dev_id() */
1565                 put_device(&cdev->dev);
1566                 break;
1567         default:
1568                 break;
1569         }
1570         return 0;
1571
1572 out_unlock:
1573         spin_unlock_irqrestore(sch->lock, flags);
1574 out:
1575         return rc;
1576 }
1577
1578 #ifdef CONFIG_CCW_CONSOLE
1579 static struct ccw_device console_cdev;
1580 static struct ccw_device_private console_private;
1581 static int console_cdev_in_use;
1582
1583 static DEFINE_SPINLOCK(ccw_console_lock);
1584
1585 spinlock_t * cio_get_console_lock(void)
1586 {
1587         return &ccw_console_lock;
1588 }
1589
1590 static int ccw_device_console_enable(struct ccw_device *cdev,
1591                                      struct subchannel *sch)
1592 {
1593         struct io_subchannel_private *io_priv = cio_get_console_priv();
1594         int rc;
1595
1596         /* Attach subchannel private data. */
1597         memset(io_priv, 0, sizeof(*io_priv));
1598         set_io_private(sch, io_priv);
1599         io_subchannel_init_fields(sch);
1600         rc = cio_commit_config(sch);
1601         if (rc)
1602                 return rc;
1603         sch->driver = &io_subchannel_driver;
1604         /* Initialize the ccw_device structure. */
1605         cdev->dev.parent= &sch->dev;
1606         sch_set_cdev(sch, cdev);
1607         io_subchannel_recog(cdev, sch);
1608         /* Now wait for the async. recognition to come to an end. */
1609         spin_lock_irq(cdev->ccwlock);
1610         while (!dev_fsm_final_state(cdev))
1611                 wait_cons_dev();
1612         rc = -EIO;
1613         if (cdev->private->state != DEV_STATE_OFFLINE)
1614                 goto out_unlock;
1615         ccw_device_online(cdev);
1616         while (!dev_fsm_final_state(cdev))
1617                 wait_cons_dev();
1618         if (cdev->private->state != DEV_STATE_ONLINE)
1619                 goto out_unlock;
1620         rc = 0;
1621 out_unlock:
1622         spin_unlock_irq(cdev->ccwlock);
1623         return rc;
1624 }
1625
1626 struct ccw_device *
1627 ccw_device_probe_console(void)
1628 {
1629         struct subchannel *sch;
1630         int ret;
1631
1632         if (xchg(&console_cdev_in_use, 1) != 0)
1633                 return ERR_PTR(-EBUSY);
1634         sch = cio_probe_console();
1635         if (IS_ERR(sch)) {
1636                 console_cdev_in_use = 0;
1637                 return (void *) sch;
1638         }
1639         memset(&console_cdev, 0, sizeof(struct ccw_device));
1640         memset(&console_private, 0, sizeof(struct ccw_device_private));
1641         console_cdev.private = &console_private;
1642         console_private.cdev = &console_cdev;
1643         console_private.int_class = IOINT_CIO;
1644         ret = ccw_device_console_enable(&console_cdev, sch);
1645         if (ret) {
1646                 cio_release_console();
1647                 console_cdev_in_use = 0;
1648                 return ERR_PTR(ret);
1649         }
1650         console_cdev.online = 1;
1651         return &console_cdev;
1652 }
1653
1654 static int ccw_device_pm_restore(struct device *dev);
1655
1656 int ccw_device_force_console(void)
1657 {
1658         if (!console_cdev_in_use)
1659                 return -ENODEV;
1660         return ccw_device_pm_restore(&console_cdev.dev);
1661 }
1662 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1663 #endif
1664
1665 /*
1666  * get ccw_device matching the busid, but only if owned by cdrv
1667  */
1668 static int
1669 __ccwdev_check_busid(struct device *dev, void *id)
1670 {
1671         char *bus_id;
1672
1673         bus_id = id;
1674
1675         return (strcmp(bus_id, dev_name(dev)) == 0);
1676 }
1677
1678
1679 /**
1680  * get_ccwdev_by_busid() - obtain device from a bus id
1681  * @cdrv: driver the device is owned by
1682  * @bus_id: bus id of the device to be searched
1683  *
1684  * This function searches all devices owned by @cdrv for a device with a bus
1685  * id matching @bus_id.
1686  * Returns:
1687  *  If a match is found, its reference count of the found device is increased
1688  *  and it is returned; else %NULL is returned.
1689  */
1690 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1691                                        const char *bus_id)
1692 {
1693         struct device *dev;
1694
1695         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1696                                  __ccwdev_check_busid);
1697
1698         return dev ? to_ccwdev(dev) : NULL;
1699 }
1700
1701 /************************** device driver handling ************************/
1702
1703 /* This is the implementation of the ccw_driver class. The probe, remove
1704  * and release methods are initially very similar to the device_driver
1705  * implementations, with the difference that they have ccw_device
1706  * arguments.
1707  *
1708  * A ccw driver also contains the information that is needed for
1709  * device matching.
1710  */
1711 static int
1712 ccw_device_probe (struct device *dev)
1713 {
1714         struct ccw_device *cdev = to_ccwdev(dev);
1715         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1716         int ret;
1717
1718         cdev->drv = cdrv; /* to let the driver call _set_online */
1719         /* Note: we interpret class 0 in this context as an uninitialized
1720          * field since it translates to a non-I/O interrupt class. */
1721         if (cdrv->int_class != 0)
1722                 cdev->private->int_class = cdrv->int_class;
1723         else
1724                 cdev->private->int_class = IOINT_CIO;
1725
1726         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1727
1728         if (ret) {
1729                 cdev->drv = NULL;
1730                 cdev->private->int_class = IOINT_CIO;
1731                 return ret;
1732         }
1733
1734         return 0;
1735 }
1736
1737 static int
1738 ccw_device_remove (struct device *dev)
1739 {
1740         struct ccw_device *cdev = to_ccwdev(dev);
1741         struct ccw_driver *cdrv = cdev->drv;
1742         int ret;
1743
1744         if (cdrv->remove)
1745                 cdrv->remove(cdev);
1746         if (cdev->online) {
1747                 cdev->online = 0;
1748                 spin_lock_irq(cdev->ccwlock);
1749                 ret = ccw_device_offline(cdev);
1750                 spin_unlock_irq(cdev->ccwlock);
1751                 if (ret == 0)
1752                         wait_event(cdev->private->wait_q,
1753                                    dev_fsm_final_state(cdev));
1754                 else
1755                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1756                                       "device 0.%x.%04x\n",
1757                                       ret, cdev->private->dev_id.ssid,
1758                                       cdev->private->dev_id.devno);
1759                 /* Give up reference obtained in ccw_device_set_online(). */
1760                 put_device(&cdev->dev);
1761         }
1762         ccw_device_set_timeout(cdev, 0);
1763         cdev->drv = NULL;
1764         cdev->private->int_class = IOINT_CIO;
1765         return 0;
1766 }
1767
1768 static void ccw_device_shutdown(struct device *dev)
1769 {
1770         struct ccw_device *cdev;
1771
1772         cdev = to_ccwdev(dev);
1773         if (cdev->drv && cdev->drv->shutdown)
1774                 cdev->drv->shutdown(cdev);
1775         disable_cmf(cdev);
1776 }
1777
1778 static int ccw_device_pm_prepare(struct device *dev)
1779 {
1780         struct ccw_device *cdev = to_ccwdev(dev);
1781
1782         if (work_pending(&cdev->private->todo_work))
1783                 return -EAGAIN;
1784         /* Fail while device is being set online/offline. */
1785         if (atomic_read(&cdev->private->onoff))
1786                 return -EAGAIN;
1787
1788         if (cdev->online && cdev->drv && cdev->drv->prepare)
1789                 return cdev->drv->prepare(cdev);
1790
1791         return 0;
1792 }
1793
1794 static void ccw_device_pm_complete(struct device *dev)
1795 {
1796         struct ccw_device *cdev = to_ccwdev(dev);
1797
1798         if (cdev->online && cdev->drv && cdev->drv->complete)
1799                 cdev->drv->complete(cdev);
1800 }
1801
1802 static int ccw_device_pm_freeze(struct device *dev)
1803 {
1804         struct ccw_device *cdev = to_ccwdev(dev);
1805         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1806         int ret, cm_enabled;
1807
1808         /* Fail suspend while device is in transistional state. */
1809         if (!dev_fsm_final_state(cdev))
1810                 return -EAGAIN;
1811         if (!cdev->online)
1812                 return 0;
1813         if (cdev->drv && cdev->drv->freeze) {
1814                 ret = cdev->drv->freeze(cdev);
1815                 if (ret)
1816                         return ret;
1817         }
1818
1819         spin_lock_irq(sch->lock);
1820         cm_enabled = cdev->private->cmb != NULL;
1821         spin_unlock_irq(sch->lock);
1822         if (cm_enabled) {
1823                 /* Don't have the css write on memory. */
1824                 ret = ccw_set_cmf(cdev, 0);
1825                 if (ret)
1826                         return ret;
1827         }
1828         /* From here on, disallow device driver I/O. */
1829         spin_lock_irq(sch->lock);
1830         ret = cio_disable_subchannel(sch);
1831         spin_unlock_irq(sch->lock);
1832
1833         return ret;
1834 }
1835
1836 static int ccw_device_pm_thaw(struct device *dev)
1837 {
1838         struct ccw_device *cdev = to_ccwdev(dev);
1839         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1840         int ret, cm_enabled;
1841
1842         if (!cdev->online)
1843                 return 0;
1844
1845         spin_lock_irq(sch->lock);
1846         /* Allow device driver I/O again. */
1847         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1848         cm_enabled = cdev->private->cmb != NULL;
1849         spin_unlock_irq(sch->lock);
1850         if (ret)
1851                 return ret;
1852
1853         if (cm_enabled) {
1854                 ret = ccw_set_cmf(cdev, 1);
1855                 if (ret)
1856                         return ret;
1857         }
1858
1859         if (cdev->drv && cdev->drv->thaw)
1860                 ret = cdev->drv->thaw(cdev);
1861
1862         return ret;
1863 }
1864
1865 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1866 {
1867         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1868
1869         spin_lock_irq(sch->lock);
1870         if (cio_is_console(sch->schid)) {
1871                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1872                 goto out_unlock;
1873         }
1874         /*
1875          * While we were sleeping, devices may have gone or become
1876          * available again. Kick re-detection.
1877          */
1878         cdev->private->flags.resuming = 1;
1879         cdev->private->path_new_mask = LPM_ANYPATH;
1880         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1881         spin_unlock_irq(sch->lock);
1882         css_wait_for_slow_path();
1883
1884         /* cdev may have been moved to a different subchannel. */
1885         sch = to_subchannel(cdev->dev.parent);
1886         spin_lock_irq(sch->lock);
1887         if (cdev->private->state != DEV_STATE_ONLINE &&
1888             cdev->private->state != DEV_STATE_OFFLINE)
1889                 goto out_unlock;
1890
1891         ccw_device_recognition(cdev);
1892         spin_unlock_irq(sch->lock);
1893         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1894                    cdev->private->state == DEV_STATE_DISCONNECTED);
1895         spin_lock_irq(sch->lock);
1896
1897 out_unlock:
1898         cdev->private->flags.resuming = 0;
1899         spin_unlock_irq(sch->lock);
1900 }
1901
1902 static int resume_handle_boxed(struct ccw_device *cdev)
1903 {
1904         cdev->private->state = DEV_STATE_BOXED;
1905         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1906                 return 0;
1907         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1908         return -ENODEV;
1909 }
1910
1911 static int resume_handle_disc(struct ccw_device *cdev)
1912 {
1913         cdev->private->state = DEV_STATE_DISCONNECTED;
1914         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1915                 return 0;
1916         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1917         return -ENODEV;
1918 }
1919
1920 static int ccw_device_pm_restore(struct device *dev)
1921 {
1922         struct ccw_device *cdev = to_ccwdev(dev);
1923         struct subchannel *sch;
1924         int ret = 0;
1925
1926         __ccw_device_pm_restore(cdev);
1927         sch = to_subchannel(cdev->dev.parent);
1928         spin_lock_irq(sch->lock);
1929         if (cio_is_console(sch->schid))
1930                 goto out_restore;
1931
1932         /* check recognition results */
1933         switch (cdev->private->state) {
1934         case DEV_STATE_OFFLINE:
1935         case DEV_STATE_ONLINE:
1936                 cdev->private->flags.donotify = 0;
1937                 break;
1938         case DEV_STATE_BOXED:
1939                 ret = resume_handle_boxed(cdev);
1940                 if (ret)
1941                         goto out_unlock;
1942                 goto out_restore;
1943         default:
1944                 ret = resume_handle_disc(cdev);
1945                 if (ret)
1946                         goto out_unlock;
1947                 goto out_restore;
1948         }
1949         /* check if the device type has changed */
1950         if (!ccw_device_test_sense_data(cdev)) {
1951                 ccw_device_update_sense_data(cdev);
1952                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1953                 ret = -ENODEV;
1954                 goto out_unlock;
1955         }
1956         if (!cdev->online)
1957                 goto out_unlock;
1958
1959         if (ccw_device_online(cdev)) {
1960                 ret = resume_handle_disc(cdev);
1961                 if (ret)
1962                         goto out_unlock;
1963                 goto out_restore;
1964         }
1965         spin_unlock_irq(sch->lock);
1966         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1967         spin_lock_irq(sch->lock);
1968
1969         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1970                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1971                 ret = -ENODEV;
1972                 goto out_unlock;
1973         }
1974
1975         /* reenable cmf, if needed */
1976         if (cdev->private->cmb) {
1977                 spin_unlock_irq(sch->lock);
1978                 ret = ccw_set_cmf(cdev, 1);
1979                 spin_lock_irq(sch->lock);
1980                 if (ret) {
1981                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1982                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
1983                                       cdev->private->dev_id.devno, ret);
1984                         ret = 0;
1985                 }
1986         }
1987
1988 out_restore:
1989         spin_unlock_irq(sch->lock);
1990         if (cdev->online && cdev->drv && cdev->drv->restore)
1991                 ret = cdev->drv->restore(cdev);
1992         return ret;
1993
1994 out_unlock:
1995         spin_unlock_irq(sch->lock);
1996         return ret;
1997 }
1998
1999 static const struct dev_pm_ops ccw_pm_ops = {
2000         .prepare = ccw_device_pm_prepare,
2001         .complete = ccw_device_pm_complete,
2002         .freeze = ccw_device_pm_freeze,
2003         .thaw = ccw_device_pm_thaw,
2004         .restore = ccw_device_pm_restore,
2005 };
2006
2007 static struct bus_type ccw_bus_type = {
2008         .name   = "ccw",
2009         .match  = ccw_bus_match,
2010         .uevent = ccw_uevent,
2011         .probe  = ccw_device_probe,
2012         .remove = ccw_device_remove,
2013         .shutdown = ccw_device_shutdown,
2014         .pm = &ccw_pm_ops,
2015 };
2016
2017 /**
2018  * ccw_driver_register() - register a ccw driver
2019  * @cdriver: driver to be registered
2020  *
2021  * This function is mainly a wrapper around driver_register().
2022  * Returns:
2023  *   %0 on success and a negative error value on failure.
2024  */
2025 int ccw_driver_register(struct ccw_driver *cdriver)
2026 {
2027         struct device_driver *drv = &cdriver->driver;
2028
2029         drv->bus = &ccw_bus_type;
2030
2031         return driver_register(drv);
2032 }
2033
2034 /**
2035  * ccw_driver_unregister() - deregister a ccw driver
2036  * @cdriver: driver to be deregistered
2037  *
2038  * This function is mainly a wrapper around driver_unregister().
2039  */
2040 void ccw_driver_unregister(struct ccw_driver *cdriver)
2041 {
2042         driver_unregister(&cdriver->driver);
2043 }
2044
2045 /* Helper func for qdio. */
2046 struct subchannel_id
2047 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2048 {
2049         struct subchannel *sch;
2050
2051         sch = to_subchannel(cdev->dev.parent);
2052         return sch->schid;
2053 }
2054
2055 static void ccw_device_todo(struct work_struct *work)
2056 {
2057         struct ccw_device_private *priv;
2058         struct ccw_device *cdev;
2059         struct subchannel *sch;
2060         enum cdev_todo todo;
2061
2062         priv = container_of(work, struct ccw_device_private, todo_work);
2063         cdev = priv->cdev;
2064         sch = to_subchannel(cdev->dev.parent);
2065         /* Find out todo. */
2066         spin_lock_irq(cdev->ccwlock);
2067         todo = priv->todo;
2068         priv->todo = CDEV_TODO_NOTHING;
2069         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2070                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2071         spin_unlock_irq(cdev->ccwlock);
2072         /* Perform todo. */
2073         switch (todo) {
2074         case CDEV_TODO_ENABLE_CMF:
2075                 cmf_reenable(cdev);
2076                 break;
2077         case CDEV_TODO_REBIND:
2078                 ccw_device_do_unbind_bind(cdev);
2079                 break;
2080         case CDEV_TODO_REGISTER:
2081                 io_subchannel_register(cdev);
2082                 break;
2083         case CDEV_TODO_UNREG_EVAL:
2084                 if (!sch_is_pseudo_sch(sch))
2085                         css_schedule_eval(sch->schid);
2086                 /* fall-through */
2087         case CDEV_TODO_UNREG:
2088                 if (sch_is_pseudo_sch(sch))
2089                         ccw_device_unregister(cdev);
2090                 else
2091                         ccw_device_call_sch_unregister(cdev);
2092                 break;
2093         default:
2094                 break;
2095         }
2096         /* Release workqueue ref. */
2097         put_device(&cdev->dev);
2098 }
2099
2100 /**
2101  * ccw_device_sched_todo - schedule ccw device operation
2102  * @cdev: ccw device
2103  * @todo: todo
2104  *
2105  * Schedule the operation identified by @todo to be performed on the slow path
2106  * workqueue. Do nothing if another operation with higher priority is already
2107  * scheduled. Needs to be called with ccwdev lock held.
2108  */
2109 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2110 {
2111         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2112                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2113                       todo);
2114         if (cdev->private->todo >= todo)
2115                 return;
2116         cdev->private->todo = todo;
2117         /* Get workqueue ref. */
2118         if (!get_device(&cdev->dev))
2119                 return;
2120         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2121                 /* Already queued, release workqueue ref. */
2122                 put_device(&cdev->dev);
2123         }
2124 }
2125
2126 /**
2127  * ccw_device_siosl() - initiate logging
2128  * @cdev: ccw device
2129  *
2130  * This function is used to invoke model-dependent logging within the channel
2131  * subsystem.
2132  */
2133 int ccw_device_siosl(struct ccw_device *cdev)
2134 {
2135         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2136
2137         return chsc_siosl(sch->schid);
2138 }
2139 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2140
2141 MODULE_LICENSE("GPL");
2142 EXPORT_SYMBOL(ccw_device_set_online);
2143 EXPORT_SYMBOL(ccw_device_set_offline);
2144 EXPORT_SYMBOL(ccw_driver_register);
2145 EXPORT_SYMBOL(ccw_driver_unregister);
2146 EXPORT_SYMBOL(get_ccwdev_by_busid);
2147 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);