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_warning("%s: The device entered boxed state while "
 368                            "being set offline\n", dev_name(&cdev->dev));
 369         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 370                 pr_warning("%s: The device stopped operating while "
 371                            "being set offline\n", 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_warning("%s: Setting the device online failed "
 433                                    "because it is boxed\n",
 434                                    dev_name(&cdev->dev));
 435                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 436                         pr_warning("%s: Setting the device online failed "
 437                                    "because it is not operational\n",
 438                                    dev_name(&cdev->dev));
 439                 }
 440                 /* Give up online reference since onlining failed. */
 441                 put_device(&cdev->dev);
 442                 return -ENODEV;
 443         }
 444         spin_unlock_irq(cdev->ccwlock);
 445         if (cdev->drv->set_online)
 446                 ret = cdev->drv->set_online(cdev);
 447         if (ret)
 448                 goto rollback;
 449
 450         spin_lock_irq(cdev->ccwlock);
 451         cdev->online = 1;
 452         spin_unlock_irq(cdev->ccwlock);
 453         return 0;
 454
 455 rollback:
 456         spin_lock_irq(cdev->ccwlock);
 457         /* Wait until a final state or DISCONNECTED is reached */
 458         while (!dev_fsm_final_state(cdev) &&
 459                cdev->private->state != DEV_STATE_DISCONNECTED) {
 460                 spin_unlock_irq(cdev->ccwlock);
 461                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 462                            cdev->private->state == DEV_STATE_DISCONNECTED));
 463                 spin_lock_irq(cdev->ccwlock);
 464         }
 465         ret2 = ccw_device_offline(cdev);
 466         if (ret2)
 467                 goto error;
 468         spin_unlock_irq(cdev->ccwlock);
 469         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 470                    cdev->private->state == DEV_STATE_DISCONNECTED));
 471         /* Give up online reference since onlining failed. */
 472         put_device(&cdev->dev);
 473         return ret;
 474
 475 error:
 476         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 477                       "device 0.%x.%04x\n",
 478                       ret2, cdev->private->dev_id.ssid,
 479                       cdev->private->dev_id.devno);
 480         cdev->private->state = DEV_STATE_OFFLINE;
 481         spin_unlock_irq(cdev->ccwlock);
 482         /* Give up online reference since onlining failed. */
 483         put_device(&cdev->dev);
 484         return ret;
 485 }
 486
 487 static int online_store_handle_offline(struct ccw_device *cdev)
 488 {
 489         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 490                 spin_lock_irq(cdev->ccwlock);
 491                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 492                 spin_unlock_irq(cdev->ccwlock);
 493                 return 0;
 494         }
 495         if (cdev->drv && cdev->drv->set_offline)
 496                 return ccw_device_set_offline(cdev);
 497         return -EINVAL;
 498 }
 499
 500 static int online_store_recog_and_online(struct ccw_device *cdev)
 501 {
 502         /* Do device recognition, if needed. */
 503         if (cdev->private->state == DEV_STATE_BOXED) {
 504                 spin_lock_irq(cdev->ccwlock);
 505                 ccw_device_recognition(cdev);
 506                 spin_unlock_irq(cdev->ccwlock);
 507                 wait_event(cdev->private->wait_q,
 508                            cdev->private->flags.recog_done);
 509                 if (cdev->private->state != DEV_STATE_OFFLINE)
 510                         /* recognition failed */
 511                         return -EAGAIN;
 512         }
 513         if (cdev->drv && cdev->drv->set_online)
 514                 return ccw_device_set_online(cdev);
 515         return -EINVAL;
 516 }
 517
 518 static int online_store_handle_online(struct ccw_device *cdev, int force)
 519 {
 520         int ret;
 521
 522         ret = online_store_recog_and_online(cdev);
 523         if (ret && !force)
 524                 return ret;
 525         if (force && cdev->private->state == DEV_STATE_BOXED) {
 526                 ret = ccw_device_stlck(cdev);
 527                 if (ret)
 528                         return ret;
 529                 if (cdev->id.cu_type == 0)
 530                         cdev->private->state = DEV_STATE_NOT_OPER;
 531                 ret = online_store_recog_and_online(cdev);
 532                 if (ret)
 533                         return ret;
 534         }
 535         return 0;
 536 }
 537
 538 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 539                              const char *buf, size_t count)
 540 {
 541         struct ccw_device *cdev = to_ccwdev(dev);
 542         int force, ret;
 543         unsigned long i;
 544
 545         /* Prevent conflict between multiple on-/offline processing requests. */
 546         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 547                 return -EAGAIN;
 548         /* Prevent conflict between internal I/Os and on-/offline processing. */
 549         if (!dev_fsm_final_state(cdev) &&
 550             cdev->private->state != DEV_STATE_DISCONNECTED) {
 551                 ret = -EAGAIN;
 552                 goto out;
 553         }
 554         /* Prevent conflict between pending work and on-/offline processing.*/
 555         if (work_pending(&cdev->private->todo_work)) {
 556                 ret = -EAGAIN;
 557                 goto out;
 558         }
 559         if (!strncmp(buf, "force\n", count)) {
 560                 force = 1;
 561                 i = 1;
 562                 ret = 0;
 563         } else {
 564                 force = 0;
 565                 ret = kstrtoul(buf, 16, &i);
 566         }
 567         if (ret)
 568                 goto out;
 569
 570         device_lock(dev);
 571         switch (i) {
 572         case 0:
 573                 ret = online_store_handle_offline(cdev);
 574                 break;
 575         case 1:
 576                 ret = online_store_handle_online(cdev, force);
 577                 break;
 578         default:
 579                 ret = -EINVAL;
 580         }
 581         device_unlock(dev);
 582
 583 out:
 584         atomic_set(&cdev->private->onoff, 0);
 585         return (ret < 0) ? ret : count;
 586 }
 587
 588 static ssize_t
 589 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 590 {
 591         struct ccw_device *cdev = to_ccwdev(dev);
 592         struct subchannel *sch;
 593
 594         if (ccw_device_is_orphan(cdev))
 595                 return sprintf(buf, "no device\n");
 596         switch (cdev->private->state) {
 597         case DEV_STATE_BOXED:
 598                 return sprintf(buf, "boxed\n");
 599         case DEV_STATE_DISCONNECTED:
 600         case DEV_STATE_DISCONNECTED_SENSE_ID:
 601         case DEV_STATE_NOT_OPER:
 602                 sch = to_subchannel(dev->parent);
 603                 if (!sch->lpm)
 604                         return sprintf(buf, "no path\n");
 605                 else
 606                         return sprintf(buf, "no device\n");
 607         default:
 608                 /* All other states considered fine. */
 609                 return sprintf(buf, "good\n");
 610         }
 611 }
 612
 613 static ssize_t
 614 initiate_logging(struct device *dev, struct device_attribute *attr,
 615                  const char *buf, size_t count)
 616 {
 617         struct subchannel *sch = to_subchannel(dev);
 618         int rc;
 619
 620         rc = chsc_siosl(sch->schid);
 621         if (rc < 0) {
 622                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
 623                            "errno=%d\n",
 624                            sch->schid.ssid, sch->schid.sch_no, rc);
 625                 return rc;
 626         }
 627         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 628                   sch->schid.ssid, sch->schid.sch_no);
 629         return count;
 630 }
 631
 632 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
 633                         char *buf)
 634 {
 635         struct subchannel *sch = to_subchannel(dev);
 636
 637         return sprintf(buf, "%02x\n", sch->vpm);
 638 }
 639
 640 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 641 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 642 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 643 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 644 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 645 static DEVICE_ATTR(online, 0644, online_show, online_store);
 646 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 647 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 648 static DEVICE_ATTR(vpm, 0444, vpm_show, NULL);
 649
 650 static struct attribute *io_subchannel_attrs[] = {
 651         &dev_attr_chpids.attr,
 652         &dev_attr_pimpampom.attr,
 653         &dev_attr_logging.attr,
 654         &dev_attr_vpm.attr,
 655         NULL,
 656 };
 657
 658 static struct attribute_group io_subchannel_attr_group = {
 659         .attrs = io_subchannel_attrs,
 660 };
 661
 662 static struct attribute * ccwdev_attrs[] = {
 663         &dev_attr_devtype.attr,
 664         &dev_attr_cutype.attr,
 665         &dev_attr_modalias.attr,
 666         &dev_attr_online.attr,
 667         &dev_attr_cmb_enable.attr,
 668         &dev_attr_availability.attr,
 669         NULL,
 670 };
 671
 672 static struct attribute_group ccwdev_attr_group = {
 673         .attrs = ccwdev_attrs,
 674 };
 675
 676 static const struct attribute_group *ccwdev_attr_groups[] = {
 677         &ccwdev_attr_group,
 678         NULL,
 679 };
 680
 681 static int ccw_device_add(struct ccw_device *cdev)
 682 {
 683         struct device *dev = &cdev->dev;
 684
 685         dev->bus = &ccw_bus_type;
 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         struct ccw_device_private *priv = cdev->private;
 761         int ret;
 762
 763         priv->cdev = cdev;
 764         priv->int_class = IRQIO_CIO;
 765         priv->state = DEV_STATE_NOT_OPER;
 766         priv->dev_id.devno = sch->schib.pmcw.dev;
 767         priv->dev_id.ssid = sch->schid.ssid;
 768         priv->schid = sch->schid;
 769
 770         INIT_WORK(&priv->todo_work, ccw_device_todo);
 771         INIT_LIST_HEAD(&priv->cmb_list);
 772         init_waitqueue_head(&priv->wait_q);
 773         init_timer(&priv->timer);
 774
 775         atomic_set(&priv->onoff, 0);
 776         cdev->ccwlock = sch->lock;
 777         cdev->dev.parent = &sch->dev;
 778         cdev->dev.release = ccw_device_release;
 779         cdev->dev.groups = ccwdev_attr_groups;
 780         /* Do first half of device_register. */
 781         device_initialize(&cdev->dev);
 782         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 783                            cdev->private->dev_id.devno);
 784         if (ret)
 785                 goto out_put;
 786         if (!get_device(&sch->dev)) {
 787                 ret = -ENODEV;
 788                 goto out_put;
 789         }
 790         priv->flags.initialized = 1;
 791         spin_lock_irq(sch->lock);
 792         sch_set_cdev(sch, cdev);
 793         spin_unlock_irq(sch->lock);
 794         return 0;
 795
 796 out_put:
 797         /* Release reference from device_initialize(). */
 798         put_device(&cdev->dev);
 799         return ret;
 800 }
 801
 802 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 803 {
 804         struct ccw_device *cdev;
 805         int ret;
 806
 807         cdev = io_subchannel_allocate_dev(sch);
 808         if (!IS_ERR(cdev)) {
 809                 ret = io_subchannel_initialize_dev(sch, cdev);
 810                 if (ret)
 811                         cdev = ERR_PTR(ret);
 812         }
 813         return cdev;
 814 }
 815
 816 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 817
 818 static void sch_create_and_recog_new_device(struct subchannel *sch)
 819 {
 820         struct ccw_device *cdev;
 821
 822         /* Need to allocate a new ccw device. */
 823         cdev = io_subchannel_create_ccwdev(sch);
 824         if (IS_ERR(cdev)) {
 825                 /* OK, we did everything we could... */
 826                 css_sch_device_unregister(sch);
 827                 return;
 828         }
 829         /* Start recognition for the new ccw device. */
 830         io_subchannel_recog(cdev, sch);
 831 }
 832
 833 /*
 834  * Register recognized device.
 835  */
 836 static void io_subchannel_register(struct ccw_device *cdev)
 837 {
 838         struct subchannel *sch;
 839         int ret, adjust_init_count = 1;
 840         unsigned long flags;
 841
 842         sch = to_subchannel(cdev->dev.parent);
 843         /*
 844          * Check if subchannel is still registered. It may have become
 845          * unregistered if a machine check hit us after finishing
 846          * device recognition but before the register work could be
 847          * queued.
 848          */
 849         if (!device_is_registered(&sch->dev))
 850                 goto out_err;
 851         css_update_ssd_info(sch);
 852         /*
 853          * io_subchannel_register() will also be called after device
 854          * recognition has been done for a boxed device (which will already
 855          * be registered). We need to reprobe since we may now have sense id
 856          * information.
 857          */
 858         if (device_is_registered(&cdev->dev)) {
 859                 if (!cdev->drv) {
 860                         ret = device_reprobe(&cdev->dev);
 861                         if (ret)
 862                                 /* We can't do much here. */
 863                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 864                                               " %d for 0.%x.%04x\n", ret,
 865                                               cdev->private->dev_id.ssid,
 866                                               cdev->private->dev_id.devno);
 867                 }
 868                 adjust_init_count = 0;
 869                 goto out;
 870         }
 871         /*
 872          * Now we know this subchannel will stay, we can throw
 873          * our delayed uevent.
 874          */
 875         if (dev_get_uevent_suppress(&sch->dev)) {
 876                 dev_set_uevent_suppress(&sch->dev, 0);
 877                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 878         }
 879         /* make it known to the system */
 880         ret = ccw_device_add(cdev);
 881         if (ret) {
 882                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 883                               cdev->private->dev_id.ssid,
 884                               cdev->private->dev_id.devno, ret);
 885                 spin_lock_irqsave(sch->lock, flags);
 886                 sch_set_cdev(sch, NULL);
 887                 spin_unlock_irqrestore(sch->lock, flags);
 888                 /* Release initial device reference. */
 889                 put_device(&cdev->dev);
 890                 goto out_err;
 891         }
 892 out:
 893         cdev->private->flags.recog_done = 1;
 894         wake_up(&cdev->private->wait_q);
 895 out_err:
 896         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 897                 wake_up(&ccw_device_init_wq);
 898 }
 899
 900 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 901 {
 902         struct subchannel *sch;
 903
 904         /* Get subchannel reference for local processing. */
 905         if (!get_device(cdev->dev.parent))
 906                 return;
 907         sch = to_subchannel(cdev->dev.parent);
 908         css_sch_device_unregister(sch);
 909         /* Release subchannel reference for local processing. */
 910         put_device(&sch->dev);
 911 }
 912
 913 /*
 914  * subchannel recognition done. Called from the state machine.
 915  */
 916 void
 917 io_subchannel_recog_done(struct ccw_device *cdev)
 918 {
 919         if (css_init_done == 0) {
 920                 cdev->private->flags.recog_done = 1;
 921                 return;
 922         }
 923         switch (cdev->private->state) {
 924         case DEV_STATE_BOXED:
 925                 /* Device did not respond in time. */
 926         case DEV_STATE_NOT_OPER:
 927                 cdev->private->flags.recog_done = 1;
 928                 /* Remove device found not operational. */
 929                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 930                 if (atomic_dec_and_test(&ccw_device_init_count))
 931                         wake_up(&ccw_device_init_wq);
 932                 break;
 933         case DEV_STATE_OFFLINE:
 934                 /*
 935                  * We can't register the device in interrupt context so
 936                  * we schedule a work item.
 937                  */
 938                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 939                 break;
 940         }
 941 }
 942
 943 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 944 {
 945         /* Increase counter of devices currently in recognition. */
 946         atomic_inc(&ccw_device_init_count);
 947
 948         /* Start async. device sensing. */
 949         spin_lock_irq(sch->lock);
 950         ccw_device_recognition(cdev);
 951         spin_unlock_irq(sch->lock);
 952 }
 953
 954 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 955                                   struct subchannel *sch)
 956 {
 957         struct subchannel *old_sch;
 958         int rc, old_enabled = 0;
 959
 960         old_sch = to_subchannel(cdev->dev.parent);
 961         /* Obtain child reference for new parent. */
 962         if (!get_device(&sch->dev))
 963                 return -ENODEV;
 964
 965         if (!sch_is_pseudo_sch(old_sch)) {
 966                 spin_lock_irq(old_sch->lock);
 967                 old_enabled = old_sch->schib.pmcw.ena;
 968                 rc = 0;
 969                 if (old_enabled)
 970                         rc = cio_disable_subchannel(old_sch);
 971                 spin_unlock_irq(old_sch->lock);
 972                 if (rc == -EBUSY) {
 973                         /* Release child reference for new parent. */
 974                         put_device(&sch->dev);
 975                         return rc;
 976                 }
 977         }
 978
 979         mutex_lock(&sch->reg_mutex);
 980         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 981         mutex_unlock(&sch->reg_mutex);
 982         if (rc) {
 983                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 984                               cdev->private->dev_id.ssid,
 985                               cdev->private->dev_id.devno, sch->schid.ssid,
 986                               sch->schib.pmcw.dev, rc);
 987                 if (old_enabled) {
 988                         /* Try to reenable the old subchannel. */
 989                         spin_lock_irq(old_sch->lock);
 990                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 991                         spin_unlock_irq(old_sch->lock);
 992                 }
 993                 /* Release child reference for new parent. */
 994                 put_device(&sch->dev);
 995                 return rc;
 996         }
 997         /* Clean up old subchannel. */
 998         if (!sch_is_pseudo_sch(old_sch)) {
 999                 spin_lock_irq(old_sch->lock);
1000                 sch_set_cdev(old_sch, NULL);
1001                 spin_unlock_irq(old_sch->lock);
1002                 css_schedule_eval(old_sch->schid);
1003         }
1004         /* Release child reference for old parent. */
1005         put_device(&old_sch->dev);
1006         /* Initialize new subchannel. */
1007         spin_lock_irq(sch->lock);
1008         cdev->private->schid = sch->schid;
1009         cdev->ccwlock = sch->lock;
1010         if (!sch_is_pseudo_sch(sch))
1011                 sch_set_cdev(sch, cdev);
1012         spin_unlock_irq(sch->lock);
1013         if (!sch_is_pseudo_sch(sch))
1014                 css_update_ssd_info(sch);
1015         return 0;
1016 }
1017
1018 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1019 {
1020         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1021         struct channel_subsystem *css = to_css(sch->dev.parent);
1022
1023         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1024 }
1025
1026 static void io_subchannel_irq(struct subchannel *sch)
1027 {
1028         struct ccw_device *cdev;
1029
1030         cdev = sch_get_cdev(sch);
1031
1032         CIO_TRACE_EVENT(6, "IRQ");
1033         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1034         if (cdev)
1035                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1036         else
1037                 inc_irq_stat(IRQIO_CIO);
1038 }
1039
1040 void io_subchannel_init_config(struct subchannel *sch)
1041 {
1042         memset(&sch->config, 0, sizeof(sch->config));
1043         sch->config.csense = 1;
1044 }
1045
1046 static void io_subchannel_init_fields(struct subchannel *sch)
1047 {
1048         if (cio_is_console(sch->schid))
1049                 sch->opm = 0xff;
1050         else
1051                 sch->opm = chp_get_sch_opm(sch);
1052         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1053         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1054
1055         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1056                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1057                       sch->schib.pmcw.dev, sch->schid.ssid,
1058                       sch->schid.sch_no, sch->schib.pmcw.pim,
1059                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1060
1061         io_subchannel_init_config(sch);
1062 }
1063
1064 /*
1065  * Note: We always return 0 so that we bind to the device even on error.
1066  * This is needed so that our remove function is called on unregister.
1067  */
1068 static int io_subchannel_probe(struct subchannel *sch)
1069 {
1070         struct io_subchannel_private *io_priv;
1071         struct ccw_device *cdev;
1072         int rc;
1073
1074         if (cio_is_console(sch->schid)) {
1075                 rc = sysfs_create_group(&sch->dev.kobj,
1076                                         &io_subchannel_attr_group);
1077                 if (rc)
1078                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1079                                       "attributes for subchannel "
1080                                       "0.%x.%04x (rc=%d)\n",
1081                                       sch->schid.ssid, sch->schid.sch_no, rc);
1082                 /*
1083                  * The console subchannel already has an associated ccw_device.
1084                  * Throw the delayed uevent for the subchannel, register
1085                  * the ccw_device and exit.
1086                  */
1087                 if (dev_get_uevent_suppress(&sch->dev)) {
1088                         /* should always be the case for the console */
1089                         dev_set_uevent_suppress(&sch->dev, 0);
1090                         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1091                 }
1092                 cdev = sch_get_cdev(sch);
1093                 rc = ccw_device_add(cdev);
1094                 if (rc) {
1095                         /* Release online reference. */
1096                         put_device(&cdev->dev);
1097                         goto out_schedule;
1098                 }
1099                 if (atomic_dec_and_test(&ccw_device_init_count))
1100                         wake_up(&ccw_device_init_wq);
1101                 return 0;
1102         }
1103         io_subchannel_init_fields(sch);
1104         rc = cio_commit_config(sch);
1105         if (rc)
1106                 goto out_schedule;
1107         rc = sysfs_create_group(&sch->dev.kobj,
1108                                 &io_subchannel_attr_group);
1109         if (rc)
1110                 goto out_schedule;
1111         /* Allocate I/O subchannel private data. */
1112         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1113         if (!io_priv)
1114                 goto out_schedule;
1115
1116         set_io_private(sch, io_priv);
1117         css_schedule_eval(sch->schid);
1118         return 0;
1119
1120 out_schedule:
1121         spin_lock_irq(sch->lock);
1122         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1123         spin_unlock_irq(sch->lock);
1124         return 0;
1125 }
1126
1127 static int
1128 io_subchannel_remove (struct subchannel *sch)
1129 {
1130         struct io_subchannel_private *io_priv = to_io_private(sch);
1131         struct ccw_device *cdev;
1132
1133         cdev = sch_get_cdev(sch);
1134         if (!cdev)
1135                 goto out_free;
1136         io_subchannel_quiesce(sch);
1137         /* Set ccw device to not operational and drop reference. */
1138         spin_lock_irq(cdev->ccwlock);
1139         sch_set_cdev(sch, NULL);
1140         set_io_private(sch, NULL);
1141         cdev->private->state = DEV_STATE_NOT_OPER;
1142         spin_unlock_irq(cdev->ccwlock);
1143         ccw_device_unregister(cdev);
1144 out_free:
1145         kfree(io_priv);
1146         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1147         return 0;
1148 }
1149
1150 static void io_subchannel_verify(struct subchannel *sch)
1151 {
1152         struct ccw_device *cdev;
1153
1154         cdev = sch_get_cdev(sch);
1155         if (cdev)
1156                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1157 }
1158
1159 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1160 {
1161         struct ccw_device *cdev;
1162
1163         cdev = sch_get_cdev(sch);
1164         if (!cdev)
1165                 return;
1166         if (cio_update_schib(sch))
1167                 goto err;
1168         /* Check for I/O on path. */
1169         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1170                 goto out;
1171         if (cdev->private->state == DEV_STATE_ONLINE) {
1172                 ccw_device_kill_io(cdev);
1173                 goto out;
1174         }
1175         if (cio_clear(sch))
1176                 goto err;
1177 out:
1178         /* Trigger path verification. */
1179         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1180         return;
1181
1182 err:
1183         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1184 }
1185
1186 static int io_subchannel_chp_event(struct subchannel *sch,
1187                                    struct chp_link *link, int event)
1188 {
1189         struct ccw_device *cdev = sch_get_cdev(sch);
1190         int mask;
1191
1192         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1193         if (!mask)
1194                 return 0;
1195         switch (event) {
1196         case CHP_VARY_OFF:
1197                 sch->opm &= ~mask;
1198                 sch->lpm &= ~mask;
1199                 if (cdev)
1200                         cdev->private->path_gone_mask |= mask;
1201                 io_subchannel_terminate_path(sch, mask);
1202                 break;
1203         case CHP_VARY_ON:
1204                 sch->opm |= mask;
1205                 sch->lpm |= mask;
1206                 if (cdev)
1207                         cdev->private->path_new_mask |= mask;
1208                 io_subchannel_verify(sch);
1209                 break;
1210         case CHP_OFFLINE:
1211                 if (cio_update_schib(sch))
1212                         return -ENODEV;
1213                 if (cdev)
1214                         cdev->private->path_gone_mask |= mask;
1215                 io_subchannel_terminate_path(sch, mask);
1216                 break;
1217         case CHP_ONLINE:
1218                 if (cio_update_schib(sch))
1219                         return -ENODEV;
1220                 sch->lpm |= mask & sch->opm;
1221                 if (cdev)
1222                         cdev->private->path_new_mask |= mask;
1223                 io_subchannel_verify(sch);
1224                 break;
1225         }
1226         return 0;
1227 }
1228
1229 static void io_subchannel_quiesce(struct subchannel *sch)
1230 {
1231         struct ccw_device *cdev;
1232         int ret;
1233
1234         spin_lock_irq(sch->lock);
1235         cdev = sch_get_cdev(sch);
1236         if (cio_is_console(sch->schid))
1237                 goto out_unlock;
1238         if (!sch->schib.pmcw.ena)
1239                 goto out_unlock;
1240         ret = cio_disable_subchannel(sch);
1241         if (ret != -EBUSY)
1242                 goto out_unlock;
1243         if (cdev->handler)
1244                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1245         while (ret == -EBUSY) {
1246                 cdev->private->state = DEV_STATE_QUIESCE;
1247                 cdev->private->iretry = 255;
1248                 ret = ccw_device_cancel_halt_clear(cdev);
1249                 if (ret == -EBUSY) {
1250                         ccw_device_set_timeout(cdev, HZ/10);
1251                         spin_unlock_irq(sch->lock);
1252                         wait_event(cdev->private->wait_q,
1253                                    cdev->private->state != DEV_STATE_QUIESCE);
1254                         spin_lock_irq(sch->lock);
1255                 }
1256                 ret = cio_disable_subchannel(sch);
1257         }
1258 out_unlock:
1259         spin_unlock_irq(sch->lock);
1260 }
1261
1262 static void io_subchannel_shutdown(struct subchannel *sch)
1263 {
1264         io_subchannel_quiesce(sch);
1265 }
1266
1267 static int device_is_disconnected(struct ccw_device *cdev)
1268 {
1269         if (!cdev)
1270                 return 0;
1271         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1272                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1273 }
1274
1275 static int recovery_check(struct device *dev, void *data)
1276 {
1277         struct ccw_device *cdev = to_ccwdev(dev);
1278         int *redo = data;
1279
1280         spin_lock_irq(cdev->ccwlock);
1281         switch (cdev->private->state) {
1282         case DEV_STATE_DISCONNECTED:
1283                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1284                               cdev->private->dev_id.ssid,
1285                               cdev->private->dev_id.devno);
1286                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1287                 *redo = 1;
1288                 break;
1289         case DEV_STATE_DISCONNECTED_SENSE_ID:
1290                 *redo = 1;
1291                 break;
1292         }
1293         spin_unlock_irq(cdev->ccwlock);
1294
1295         return 0;
1296 }
1297
1298 static void recovery_work_func(struct work_struct *unused)
1299 {
1300         int redo = 0;
1301
1302         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1303         if (redo) {
1304                 spin_lock_irq(&recovery_lock);
1305                 if (!timer_pending(&recovery_timer)) {
1306                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1307                                 recovery_phase++;
1308                         mod_timer(&recovery_timer, jiffies +
1309                                   recovery_delay[recovery_phase] * HZ);
1310                 }
1311                 spin_unlock_irq(&recovery_lock);
1312         } else
1313                 CIO_MSG_EVENT(4, "recovery: end\n");
1314 }
1315
1316 static DECLARE_WORK(recovery_work, recovery_work_func);
1317
1318 static void recovery_func(unsigned long data)
1319 {
1320         /*
1321          * We can't do our recovery in softirq context and it's not
1322          * performance critical, so we schedule it.
1323          */
1324         schedule_work(&recovery_work);
1325 }
1326
1327 static void ccw_device_schedule_recovery(void)
1328 {
1329         unsigned long flags;
1330
1331         CIO_MSG_EVENT(4, "recovery: schedule\n");
1332         spin_lock_irqsave(&recovery_lock, flags);
1333         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1334                 recovery_phase = 0;
1335                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1336         }
1337         spin_unlock_irqrestore(&recovery_lock, flags);
1338 }
1339
1340 static int purge_fn(struct device *dev, void *data)
1341 {
1342         struct ccw_device *cdev = to_ccwdev(dev);
1343         struct ccw_dev_id *id = &cdev->private->dev_id;
1344
1345         spin_lock_irq(cdev->ccwlock);
1346         if (is_blacklisted(id->ssid, id->devno) &&
1347             (cdev->private->state == DEV_STATE_OFFLINE) &&
1348             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1349                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1350                               id->devno);
1351                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1352                 atomic_set(&cdev->private->onoff, 0);
1353         }
1354         spin_unlock_irq(cdev->ccwlock);
1355         /* Abort loop in case of pending signal. */
1356         if (signal_pending(current))
1357                 return -EINTR;
1358
1359         return 0;
1360 }
1361
1362 /**
1363  * ccw_purge_blacklisted - purge unused, blacklisted devices
1364  *
1365  * Unregister all ccw devices that are offline and on the blacklist.
1366  */
1367 int ccw_purge_blacklisted(void)
1368 {
1369         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1370         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1371         return 0;
1372 }
1373
1374 void ccw_device_set_disconnected(struct ccw_device *cdev)
1375 {
1376         if (!cdev)
1377                 return;
1378         ccw_device_set_timeout(cdev, 0);
1379         cdev->private->flags.fake_irb = 0;
1380         cdev->private->state = DEV_STATE_DISCONNECTED;
1381         if (cdev->online)
1382                 ccw_device_schedule_recovery();
1383 }
1384
1385 void ccw_device_set_notoper(struct ccw_device *cdev)
1386 {
1387         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1388
1389         CIO_TRACE_EVENT(2, "notoper");
1390         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1391         ccw_device_set_timeout(cdev, 0);
1392         cio_disable_subchannel(sch);
1393         cdev->private->state = DEV_STATE_NOT_OPER;
1394 }
1395
1396 enum io_sch_action {
1397         IO_SCH_UNREG,
1398         IO_SCH_ORPH_UNREG,
1399         IO_SCH_ATTACH,
1400         IO_SCH_UNREG_ATTACH,
1401         IO_SCH_ORPH_ATTACH,
1402         IO_SCH_REPROBE,
1403         IO_SCH_VERIFY,
1404         IO_SCH_DISC,
1405         IO_SCH_NOP,
1406 };
1407
1408 static enum io_sch_action sch_get_action(struct subchannel *sch)
1409 {
1410         struct ccw_device *cdev;
1411
1412         cdev = sch_get_cdev(sch);
1413         if (cio_update_schib(sch)) {
1414                 /* Not operational. */
1415                 if (!cdev)
1416                         return IO_SCH_UNREG;
1417                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1418                         return IO_SCH_UNREG;
1419                 return IO_SCH_ORPH_UNREG;
1420         }
1421         /* Operational. */
1422         if (!cdev)
1423                 return IO_SCH_ATTACH;
1424         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1425                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1426                         return IO_SCH_UNREG_ATTACH;
1427                 return IO_SCH_ORPH_ATTACH;
1428         }
1429         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1430                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1431                         return IO_SCH_UNREG;
1432                 return IO_SCH_DISC;
1433         }
1434         if (device_is_disconnected(cdev))
1435                 return IO_SCH_REPROBE;
1436         if (cdev->online && !cdev->private->flags.resuming)
1437                 return IO_SCH_VERIFY;
1438         if (cdev->private->state == DEV_STATE_NOT_OPER)
1439                 return IO_SCH_UNREG_ATTACH;
1440         return IO_SCH_NOP;
1441 }
1442
1443 /**
1444  * io_subchannel_sch_event - process subchannel event
1445  * @sch: subchannel
1446  * @process: non-zero if function is called in process context
1447  *
1448  * An unspecified event occurred for this subchannel. Adjust data according
1449  * to the current operational state of the subchannel and device. Return
1450  * zero when the event has been handled sufficiently or -EAGAIN when this
1451  * function should be called again in process context.
1452  */
1453 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1454 {
1455         unsigned long flags;
1456         struct ccw_device *cdev;
1457         struct ccw_dev_id dev_id;
1458         enum io_sch_action action;
1459         int rc = -EAGAIN;
1460
1461         spin_lock_irqsave(sch->lock, flags);
1462         if (!device_is_registered(&sch->dev))
1463                 goto out_unlock;
1464         if (work_pending(&sch->todo_work))
1465                 goto out_unlock;
1466         cdev = sch_get_cdev(sch);
1467         if (cdev && work_pending(&cdev->private->todo_work))
1468                 goto out_unlock;
1469         action = sch_get_action(sch);
1470         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1471                       sch->schid.ssid, sch->schid.sch_no, process,
1472                       action);
1473         /* Perform immediate actions while holding the lock. */
1474         switch (action) {
1475         case IO_SCH_REPROBE:
1476                 /* Trigger device recognition. */
1477                 ccw_device_trigger_reprobe(cdev);
1478                 rc = 0;
1479                 goto out_unlock;
1480         case IO_SCH_VERIFY:
1481                 /* Trigger path verification. */
1482                 io_subchannel_verify(sch);
1483                 rc = 0;
1484                 goto out_unlock;
1485         case IO_SCH_DISC:
1486                 ccw_device_set_disconnected(cdev);
1487                 rc = 0;
1488                 goto out_unlock;
1489         case IO_SCH_ORPH_UNREG:
1490         case IO_SCH_ORPH_ATTACH:
1491                 ccw_device_set_disconnected(cdev);
1492                 break;
1493         case IO_SCH_UNREG_ATTACH:
1494         case IO_SCH_UNREG:
1495                 if (!cdev)
1496                         break;
1497                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1498                         /*
1499                          * Note: delayed work triggered by this event
1500                          * and repeated calls to sch_event are synchronized
1501                          * by the above check for work_pending(cdev).
1502                          */
1503                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1504                 } else
1505                         ccw_device_set_notoper(cdev);
1506                 break;
1507         case IO_SCH_NOP:
1508                 rc = 0;
1509                 goto out_unlock;
1510         default:
1511                 break;
1512         }
1513         spin_unlock_irqrestore(sch->lock, flags);
1514         /* All other actions require process context. */
1515         if (!process)
1516                 goto out;
1517         /* Handle attached ccw device. */
1518         switch (action) {
1519         case IO_SCH_ORPH_UNREG:
1520         case IO_SCH_ORPH_ATTACH:
1521                 /* Move ccw device to orphanage. */
1522                 rc = ccw_device_move_to_orph(cdev);
1523                 if (rc)
1524                         goto out;
1525                 break;
1526         case IO_SCH_UNREG_ATTACH:
1527                 spin_lock_irqsave(sch->lock, flags);
1528                 if (cdev->private->flags.resuming) {
1529                         /* Device will be handled later. */
1530                         rc = 0;
1531                         goto out_unlock;
1532                 }
1533                 sch_set_cdev(sch, NULL);
1534                 spin_unlock_irqrestore(sch->lock, flags);
1535                 /* Unregister ccw device. */
1536                 ccw_device_unregister(cdev);
1537                 break;
1538         default:
1539                 break;
1540         }
1541         /* Handle subchannel. */
1542         switch (action) {
1543         case IO_SCH_ORPH_UNREG:
1544         case IO_SCH_UNREG:
1545                 if (!cdev || !cdev->private->flags.resuming)
1546                         css_sch_device_unregister(sch);
1547                 break;
1548         case IO_SCH_ORPH_ATTACH:
1549         case IO_SCH_UNREG_ATTACH:
1550         case IO_SCH_ATTACH:
1551                 dev_id.ssid = sch->schid.ssid;
1552                 dev_id.devno = sch->schib.pmcw.dev;
1553                 cdev = get_ccwdev_by_dev_id(&dev_id);
1554                 if (!cdev) {
1555                         sch_create_and_recog_new_device(sch);
1556                         break;
1557                 }
1558                 rc = ccw_device_move_to_sch(cdev, sch);
1559                 if (rc) {
1560                         /* Release reference from get_ccwdev_by_dev_id() */
1561                         put_device(&cdev->dev);
1562                         goto out;
1563                 }
1564                 spin_lock_irqsave(sch->lock, flags);
1565                 ccw_device_trigger_reprobe(cdev);
1566                 spin_unlock_irqrestore(sch->lock, flags);
1567                 /* Release reference from get_ccwdev_by_dev_id() */
1568                 put_device(&cdev->dev);
1569                 break;
1570         default:
1571                 break;
1572         }
1573         return 0;
1574
1575 out_unlock:
1576         spin_unlock_irqrestore(sch->lock, flags);
1577 out:
1578         return rc;
1579 }
1580
1581 static void ccw_device_set_int_class(struct ccw_device *cdev)
1582 {
1583         struct ccw_driver *cdrv = cdev->drv;
1584
1585         /* Note: we interpret class 0 in this context as an uninitialized
1586          * field since it translates to a non-I/O interrupt class. */
1587         if (cdrv->int_class != 0)
1588                 cdev->private->int_class = cdrv->int_class;
1589         else
1590                 cdev->private->int_class = IRQIO_CIO;
1591 }
1592
1593 #ifdef CONFIG_CCW_CONSOLE
1594 int __init ccw_device_enable_console(struct ccw_device *cdev)
1595 {
1596         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1597         int rc;
1598
1599         if (!cdev->drv || !cdev->handler)
1600                 return -EINVAL;
1601
1602         io_subchannel_init_fields(sch);
1603         rc = cio_commit_config(sch);
1604         if (rc)
1605                 return rc;
1606         sch->driver = &io_subchannel_driver;
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                 ccw_device_wait_idle(cdev);
1612
1613         /* Hold on to an extra reference while device is online. */
1614         get_device(&cdev->dev);
1615         rc = ccw_device_online(cdev);
1616         if (rc)
1617                 goto out_unlock;
1618
1619         while (!dev_fsm_final_state(cdev))
1620                 ccw_device_wait_idle(cdev);
1621
1622         if (cdev->private->state == DEV_STATE_ONLINE)
1623                 cdev->online = 1;
1624         else
1625                 rc = -EIO;
1626 out_unlock:
1627         spin_unlock_irq(cdev->ccwlock);
1628         if (rc) /* Give up online reference since onlining failed. */
1629                 put_device(&cdev->dev);
1630         return rc;
1631 }
1632
1633 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1634 {
1635         struct io_subchannel_private *io_priv;
1636         struct ccw_device *cdev;
1637         struct subchannel *sch;
1638
1639         sch = cio_probe_console();
1640         if (IS_ERR(sch))
1641                 return ERR_CAST(sch);
1642
1643         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1644         if (!io_priv) {
1645                 put_device(&sch->dev);
1646                 return ERR_PTR(-ENOMEM);
1647         }
1648         set_io_private(sch, io_priv);
1649         cdev = io_subchannel_create_ccwdev(sch);
1650         if (IS_ERR(cdev)) {
1651                 put_device(&sch->dev);
1652                 kfree(io_priv);
1653                 return cdev;
1654         }
1655         cdev->drv = drv;
1656         ccw_device_set_int_class(cdev);
1657         return cdev;
1658 }
1659
1660 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1661 {
1662         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1663         struct io_subchannel_private *io_priv = to_io_private(sch);
1664
1665         set_io_private(sch, NULL);
1666         put_device(&sch->dev);
1667         put_device(&cdev->dev);
1668         kfree(io_priv);
1669 }
1670
1671 /**
1672  * ccw_device_wait_idle() - busy wait for device to become idle
1673  * @cdev: ccw device
1674  *
1675  * Poll until activity control is zero, that is, no function or data
1676  * transfer is pending/active.
1677  * Called with device lock being held.
1678  */
1679 void ccw_device_wait_idle(struct ccw_device *cdev)
1680 {
1681         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1682
1683         while (1) {
1684                 cio_tsch(sch);
1685                 if (sch->schib.scsw.cmd.actl == 0)
1686                         break;
1687                 udelay_simple(100);
1688         }
1689 }
1690
1691 static int ccw_device_pm_restore(struct device *dev);
1692
1693 int ccw_device_force_console(struct ccw_device *cdev)
1694 {
1695         return ccw_device_pm_restore(&cdev->dev);
1696 }
1697 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1698 #endif
1699
1700 /*
1701  * get ccw_device matching the busid, but only if owned by cdrv
1702  */
1703 static int
1704 __ccwdev_check_busid(struct device *dev, void *id)
1705 {
1706         char *bus_id;
1707
1708         bus_id = id;
1709
1710         return (strcmp(bus_id, dev_name(dev)) == 0);
1711 }
1712
1713
1714 /**
1715  * get_ccwdev_by_busid() - obtain device from a bus id
1716  * @cdrv: driver the device is owned by
1717  * @bus_id: bus id of the device to be searched
1718  *
1719  * This function searches all devices owned by @cdrv for a device with a bus
1720  * id matching @bus_id.
1721  * Returns:
1722  *  If a match is found, its reference count of the found device is increased
1723  *  and it is returned; else %NULL is returned.
1724  */
1725 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1726                                        const char *bus_id)
1727 {
1728         struct device *dev;
1729
1730         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1731                                  __ccwdev_check_busid);
1732
1733         return dev ? to_ccwdev(dev) : NULL;
1734 }
1735
1736 /************************** device driver handling ************************/
1737
1738 /* This is the implementation of the ccw_driver class. The probe, remove
1739  * and release methods are initially very similar to the device_driver
1740  * implementations, with the difference that they have ccw_device
1741  * arguments.
1742  *
1743  * A ccw driver also contains the information that is needed for
1744  * device matching.
1745  */
1746 static int
1747 ccw_device_probe (struct device *dev)
1748 {
1749         struct ccw_device *cdev = to_ccwdev(dev);
1750         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1751         int ret;
1752
1753         cdev->drv = cdrv; /* to let the driver call _set_online */
1754         ccw_device_set_int_class(cdev);
1755         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1756         if (ret) {
1757                 cdev->drv = NULL;
1758                 cdev->private->int_class = IRQIO_CIO;
1759                 return ret;
1760         }
1761
1762         return 0;
1763 }
1764
1765 static int ccw_device_remove(struct device *dev)
1766 {
1767         struct ccw_device *cdev = to_ccwdev(dev);
1768         struct ccw_driver *cdrv = cdev->drv;
1769         int ret;
1770
1771         if (cdrv->remove)
1772                 cdrv->remove(cdev);
1773
1774         spin_lock_irq(cdev->ccwlock);
1775         if (cdev->online) {
1776                 cdev->online = 0;
1777                 ret = ccw_device_offline(cdev);
1778                 spin_unlock_irq(cdev->ccwlock);
1779                 if (ret == 0)
1780                         wait_event(cdev->private->wait_q,
1781                                    dev_fsm_final_state(cdev));
1782                 else
1783                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1784                                       "device 0.%x.%04x\n",
1785                                       ret, cdev->private->dev_id.ssid,
1786                                       cdev->private->dev_id.devno);
1787                 /* Give up reference obtained in ccw_device_set_online(). */
1788                 put_device(&cdev->dev);
1789                 spin_lock_irq(cdev->ccwlock);
1790         }
1791         ccw_device_set_timeout(cdev, 0);
1792         cdev->drv = NULL;
1793         cdev->private->int_class = IRQIO_CIO;
1794         spin_unlock_irq(cdev->ccwlock);
1795         __disable_cmf(cdev);
1796
1797         return 0;
1798 }
1799
1800 static void ccw_device_shutdown(struct device *dev)
1801 {
1802         struct ccw_device *cdev;
1803
1804         cdev = to_ccwdev(dev);
1805         if (cdev->drv && cdev->drv->shutdown)
1806                 cdev->drv->shutdown(cdev);
1807         __disable_cmf(cdev);
1808 }
1809
1810 static int ccw_device_pm_prepare(struct device *dev)
1811 {
1812         struct ccw_device *cdev = to_ccwdev(dev);
1813
1814         if (work_pending(&cdev->private->todo_work))
1815                 return -EAGAIN;
1816         /* Fail while device is being set online/offline. */
1817         if (atomic_read(&cdev->private->onoff))
1818                 return -EAGAIN;
1819
1820         if (cdev->online && cdev->drv && cdev->drv->prepare)
1821                 return cdev->drv->prepare(cdev);
1822
1823         return 0;
1824 }
1825
1826 static void ccw_device_pm_complete(struct device *dev)
1827 {
1828         struct ccw_device *cdev = to_ccwdev(dev);
1829
1830         if (cdev->online && cdev->drv && cdev->drv->complete)
1831                 cdev->drv->complete(cdev);
1832 }
1833
1834 static int ccw_device_pm_freeze(struct device *dev)
1835 {
1836         struct ccw_device *cdev = to_ccwdev(dev);
1837         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1838         int ret, cm_enabled;
1839
1840         /* Fail suspend while device is in transistional state. */
1841         if (!dev_fsm_final_state(cdev))
1842                 return -EAGAIN;
1843         if (!cdev->online)
1844                 return 0;
1845         if (cdev->drv && cdev->drv->freeze) {
1846                 ret = cdev->drv->freeze(cdev);
1847                 if (ret)
1848                         return ret;
1849         }
1850
1851         spin_lock_irq(sch->lock);
1852         cm_enabled = cdev->private->cmb != NULL;
1853         spin_unlock_irq(sch->lock);
1854         if (cm_enabled) {
1855                 /* Don't have the css write on memory. */
1856                 ret = ccw_set_cmf(cdev, 0);
1857                 if (ret)
1858                         return ret;
1859         }
1860         /* From here on, disallow device driver I/O. */
1861         spin_lock_irq(sch->lock);
1862         ret = cio_disable_subchannel(sch);
1863         spin_unlock_irq(sch->lock);
1864
1865         return ret;
1866 }
1867
1868 static int ccw_device_pm_thaw(struct device *dev)
1869 {
1870         struct ccw_device *cdev = to_ccwdev(dev);
1871         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1872         int ret, cm_enabled;
1873
1874         if (!cdev->online)
1875                 return 0;
1876
1877         spin_lock_irq(sch->lock);
1878         /* Allow device driver I/O again. */
1879         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1880         cm_enabled = cdev->private->cmb != NULL;
1881         spin_unlock_irq(sch->lock);
1882         if (ret)
1883                 return ret;
1884
1885         if (cm_enabled) {
1886                 ret = ccw_set_cmf(cdev, 1);
1887                 if (ret)
1888                         return ret;
1889         }
1890
1891         if (cdev->drv && cdev->drv->thaw)
1892                 ret = cdev->drv->thaw(cdev);
1893
1894         return ret;
1895 }
1896
1897 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1898 {
1899         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1900
1901         spin_lock_irq(sch->lock);
1902         if (cio_is_console(sch->schid)) {
1903                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1904                 goto out_unlock;
1905         }
1906         /*
1907          * While we were sleeping, devices may have gone or become
1908          * available again. Kick re-detection.
1909          */
1910         cdev->private->flags.resuming = 1;
1911         cdev->private->path_new_mask = LPM_ANYPATH;
1912         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1913         spin_unlock_irq(sch->lock);
1914         css_wait_for_slow_path();
1915
1916         /* cdev may have been moved to a different subchannel. */
1917         sch = to_subchannel(cdev->dev.parent);
1918         spin_lock_irq(sch->lock);
1919         if (cdev->private->state != DEV_STATE_ONLINE &&
1920             cdev->private->state != DEV_STATE_OFFLINE)
1921                 goto out_unlock;
1922
1923         ccw_device_recognition(cdev);
1924         spin_unlock_irq(sch->lock);
1925         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1926                    cdev->private->state == DEV_STATE_DISCONNECTED);
1927         spin_lock_irq(sch->lock);
1928
1929 out_unlock:
1930         cdev->private->flags.resuming = 0;
1931         spin_unlock_irq(sch->lock);
1932 }
1933
1934 static int resume_handle_boxed(struct ccw_device *cdev)
1935 {
1936         cdev->private->state = DEV_STATE_BOXED;
1937         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1938                 return 0;
1939         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1940         return -ENODEV;
1941 }
1942
1943 static int resume_handle_disc(struct ccw_device *cdev)
1944 {
1945         cdev->private->state = DEV_STATE_DISCONNECTED;
1946         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1947                 return 0;
1948         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1949         return -ENODEV;
1950 }
1951
1952 static int ccw_device_pm_restore(struct device *dev)
1953 {
1954         struct ccw_device *cdev = to_ccwdev(dev);
1955         struct subchannel *sch;
1956         int ret = 0;
1957
1958         __ccw_device_pm_restore(cdev);
1959         sch = to_subchannel(cdev->dev.parent);
1960         spin_lock_irq(sch->lock);
1961         if (cio_is_console(sch->schid))
1962                 goto out_restore;
1963
1964         /* check recognition results */
1965         switch (cdev->private->state) {
1966         case DEV_STATE_OFFLINE:
1967         case DEV_STATE_ONLINE:
1968                 cdev->private->flags.donotify = 0;
1969                 break;
1970         case DEV_STATE_BOXED:
1971                 ret = resume_handle_boxed(cdev);
1972                 if (ret)
1973                         goto out_unlock;
1974                 goto out_restore;
1975         default:
1976                 ret = resume_handle_disc(cdev);
1977                 if (ret)
1978                         goto out_unlock;
1979                 goto out_restore;
1980         }
1981         /* check if the device type has changed */
1982         if (!ccw_device_test_sense_data(cdev)) {
1983                 ccw_device_update_sense_data(cdev);
1984                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1985                 ret = -ENODEV;
1986                 goto out_unlock;
1987         }
1988         if (!cdev->online)
1989                 goto out_unlock;
1990
1991         if (ccw_device_online(cdev)) {
1992                 ret = resume_handle_disc(cdev);
1993                 if (ret)
1994                         goto out_unlock;
1995                 goto out_restore;
1996         }
1997         spin_unlock_irq(sch->lock);
1998         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1999         spin_lock_irq(sch->lock);
2000
2001         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
2002                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
2003                 ret = -ENODEV;
2004                 goto out_unlock;
2005         }
2006
2007         /* reenable cmf, if needed */
2008         if (cdev->private->cmb) {
2009                 spin_unlock_irq(sch->lock);
2010                 ret = ccw_set_cmf(cdev, 1);
2011                 spin_lock_irq(sch->lock);
2012                 if (ret) {
2013                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2014                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
2015                                       cdev->private->dev_id.devno, ret);
2016                         ret = 0;
2017                 }
2018         }
2019
2020 out_restore:
2021         spin_unlock_irq(sch->lock);
2022         if (cdev->online && cdev->drv && cdev->drv->restore)
2023                 ret = cdev->drv->restore(cdev);
2024         return ret;
2025
2026 out_unlock:
2027         spin_unlock_irq(sch->lock);
2028         return ret;
2029 }
2030
2031 static const struct dev_pm_ops ccw_pm_ops = {
2032         .prepare = ccw_device_pm_prepare,
2033         .complete = ccw_device_pm_complete,
2034         .freeze = ccw_device_pm_freeze,
2035         .thaw = ccw_device_pm_thaw,
2036         .restore = ccw_device_pm_restore,
2037 };
2038
2039 static struct bus_type ccw_bus_type = {
2040         .name   = "ccw",
2041         .match  = ccw_bus_match,
2042         .uevent = ccw_uevent,
2043         .probe  = ccw_device_probe,
2044         .remove = ccw_device_remove,
2045         .shutdown = ccw_device_shutdown,
2046         .pm = &ccw_pm_ops,
2047 };
2048
2049 /**
2050  * ccw_driver_register() - register a ccw driver
2051  * @cdriver: driver to be registered
2052  *
2053  * This function is mainly a wrapper around driver_register().
2054  * Returns:
2055  *   %0 on success and a negative error value on failure.
2056  */
2057 int ccw_driver_register(struct ccw_driver *cdriver)
2058 {
2059         struct device_driver *drv = &cdriver->driver;
2060
2061         drv->bus = &ccw_bus_type;
2062
2063         return driver_register(drv);
2064 }
2065
2066 /**
2067  * ccw_driver_unregister() - deregister a ccw driver
2068  * @cdriver: driver to be deregistered
2069  *
2070  * This function is mainly a wrapper around driver_unregister().
2071  */
2072 void ccw_driver_unregister(struct ccw_driver *cdriver)
2073 {
2074         driver_unregister(&cdriver->driver);
2075 }
2076
2077 static void ccw_device_todo(struct work_struct *work)
2078 {
2079         struct ccw_device_private *priv;
2080         struct ccw_device *cdev;
2081         struct subchannel *sch;
2082         enum cdev_todo todo;
2083
2084         priv = container_of(work, struct ccw_device_private, todo_work);
2085         cdev = priv->cdev;
2086         sch = to_subchannel(cdev->dev.parent);
2087         /* Find out todo. */
2088         spin_lock_irq(cdev->ccwlock);
2089         todo = priv->todo;
2090         priv->todo = CDEV_TODO_NOTHING;
2091         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2092                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2093         spin_unlock_irq(cdev->ccwlock);
2094         /* Perform todo. */
2095         switch (todo) {
2096         case CDEV_TODO_ENABLE_CMF:
2097                 cmf_reenable(cdev);
2098                 break;
2099         case CDEV_TODO_REBIND:
2100                 ccw_device_do_unbind_bind(cdev);
2101                 break;
2102         case CDEV_TODO_REGISTER:
2103                 io_subchannel_register(cdev);
2104                 break;
2105         case CDEV_TODO_UNREG_EVAL:
2106                 if (!sch_is_pseudo_sch(sch))
2107                         css_schedule_eval(sch->schid);
2108                 /* fall-through */
2109         case CDEV_TODO_UNREG:
2110                 if (sch_is_pseudo_sch(sch))
2111                         ccw_device_unregister(cdev);
2112                 else
2113                         ccw_device_call_sch_unregister(cdev);
2114                 break;
2115         default:
2116                 break;
2117         }
2118         /* Release workqueue ref. */
2119         put_device(&cdev->dev);
2120 }
2121
2122 /**
2123  * ccw_device_sched_todo - schedule ccw device operation
2124  * @cdev: ccw device
2125  * @todo: todo
2126  *
2127  * Schedule the operation identified by @todo to be performed on the slow path
2128  * workqueue. Do nothing if another operation with higher priority is already
2129  * scheduled. Needs to be called with ccwdev lock held.
2130  */
2131 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2132 {
2133         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2134                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2135                       todo);
2136         if (cdev->private->todo >= todo)
2137                 return;
2138         cdev->private->todo = todo;
2139         /* Get workqueue ref. */
2140         if (!get_device(&cdev->dev))
2141                 return;
2142         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2143                 /* Already queued, release workqueue ref. */
2144                 put_device(&cdev->dev);
2145         }
2146 }
2147
2148 /**
2149  * ccw_device_siosl() - initiate logging
2150  * @cdev: ccw device
2151  *
2152  * This function is used to invoke model-dependent logging within the channel
2153  * subsystem.
2154  */
2155 int ccw_device_siosl(struct ccw_device *cdev)
2156 {
2157         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2158
2159         return chsc_siosl(sch->schid);
2160 }
2161 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2162
2163 MODULE_LICENSE("GPL");
2164 EXPORT_SYMBOL(ccw_device_set_online);
2165 EXPORT_SYMBOL(ccw_device_set_offline);
2166 EXPORT_SYMBOL(ccw_driver_register);
2167 EXPORT_SYMBOL(ccw_driver_unregister);
2168 EXPORT_SYMBOL(get_ccwdev_by_busid);