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         dev_set_uevent_suppress(&sch->dev, 0);
 876         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 877         /* make it known to the system */
 878         ret = ccw_device_add(cdev);
 879         if (ret) {
 880                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 881                               cdev->private->dev_id.ssid,
 882                               cdev->private->dev_id.devno, ret);
 883                 spin_lock_irqsave(sch->lock, flags);
 884                 sch_set_cdev(sch, NULL);
 885                 spin_unlock_irqrestore(sch->lock, flags);
 886                 /* Release initial device reference. */
 887                 put_device(&cdev->dev);
 888                 goto out_err;
 889         }
 890 out:
 891         cdev->private->flags.recog_done = 1;
 892         wake_up(&cdev->private->wait_q);
 893 out_err:
 894         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 895                 wake_up(&ccw_device_init_wq);
 896 }
 897
 898 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 899 {
 900         struct subchannel *sch;
 901
 902         /* Get subchannel reference for local processing. */
 903         if (!get_device(cdev->dev.parent))
 904                 return;
 905         sch = to_subchannel(cdev->dev.parent);
 906         css_sch_device_unregister(sch);
 907         /* Release subchannel reference for local processing. */
 908         put_device(&sch->dev);
 909 }
 910
 911 /*
 912  * subchannel recognition done. Called from the state machine.
 913  */
 914 void
 915 io_subchannel_recog_done(struct ccw_device *cdev)
 916 {
 917         if (css_init_done == 0) {
 918                 cdev->private->flags.recog_done = 1;
 919                 return;
 920         }
 921         switch (cdev->private->state) {
 922         case DEV_STATE_BOXED:
 923                 /* Device did not respond in time. */
 924         case DEV_STATE_NOT_OPER:
 925                 cdev->private->flags.recog_done = 1;
 926                 /* Remove device found not operational. */
 927                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 928                 if (atomic_dec_and_test(&ccw_device_init_count))
 929                         wake_up(&ccw_device_init_wq);
 930                 break;
 931         case DEV_STATE_OFFLINE:
 932                 /*
 933                  * We can't register the device in interrupt context so
 934                  * we schedule a work item.
 935                  */
 936                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 937                 break;
 938         }
 939 }
 940
 941 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 942 {
 943         /* Increase counter of devices currently in recognition. */
 944         atomic_inc(&ccw_device_init_count);
 945
 946         /* Start async. device sensing. */
 947         spin_lock_irq(sch->lock);
 948         ccw_device_recognition(cdev);
 949         spin_unlock_irq(sch->lock);
 950 }
 951
 952 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 953                                   struct subchannel *sch)
 954 {
 955         struct subchannel *old_sch;
 956         int rc, old_enabled = 0;
 957
 958         old_sch = to_subchannel(cdev->dev.parent);
 959         /* Obtain child reference for new parent. */
 960         if (!get_device(&sch->dev))
 961                 return -ENODEV;
 962
 963         if (!sch_is_pseudo_sch(old_sch)) {
 964                 spin_lock_irq(old_sch->lock);
 965                 old_enabled = old_sch->schib.pmcw.ena;
 966                 rc = 0;
 967                 if (old_enabled)
 968                         rc = cio_disable_subchannel(old_sch);
 969                 spin_unlock_irq(old_sch->lock);
 970                 if (rc == -EBUSY) {
 971                         /* Release child reference for new parent. */
 972                         put_device(&sch->dev);
 973                         return rc;
 974                 }
 975         }
 976
 977         mutex_lock(&sch->reg_mutex);
 978         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 979         mutex_unlock(&sch->reg_mutex);
 980         if (rc) {
 981                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 982                               cdev->private->dev_id.ssid,
 983                               cdev->private->dev_id.devno, sch->schid.ssid,
 984                               sch->schib.pmcw.dev, rc);
 985                 if (old_enabled) {
 986                         /* Try to reenable the old subchannel. */
 987                         spin_lock_irq(old_sch->lock);
 988                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 989                         spin_unlock_irq(old_sch->lock);
 990                 }
 991                 /* Release child reference for new parent. */
 992                 put_device(&sch->dev);
 993                 return rc;
 994         }
 995         /* Clean up old subchannel. */
 996         if (!sch_is_pseudo_sch(old_sch)) {
 997                 spin_lock_irq(old_sch->lock);
 998                 sch_set_cdev(old_sch, NULL);
 999                 spin_unlock_irq(old_sch->lock);
1000                 css_schedule_eval(old_sch->schid);
1001         }
1002         /* Release child reference for old parent. */
1003         put_device(&old_sch->dev);
1004         /* Initialize new subchannel. */
1005         spin_lock_irq(sch->lock);
1006         cdev->private->schid = sch->schid;
1007         cdev->ccwlock = sch->lock;
1008         if (!sch_is_pseudo_sch(sch))
1009                 sch_set_cdev(sch, cdev);
1010         spin_unlock_irq(sch->lock);
1011         if (!sch_is_pseudo_sch(sch))
1012                 css_update_ssd_info(sch);
1013         return 0;
1014 }
1015
1016 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1017 {
1018         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1019         struct channel_subsystem *css = to_css(sch->dev.parent);
1020
1021         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1022 }
1023
1024 static void io_subchannel_irq(struct subchannel *sch)
1025 {
1026         struct ccw_device *cdev;
1027
1028         cdev = sch_get_cdev(sch);
1029
1030         CIO_TRACE_EVENT(6, "IRQ");
1031         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1032         if (cdev)
1033                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1034         else
1035                 inc_irq_stat(IRQIO_CIO);
1036 }
1037
1038 void io_subchannel_init_config(struct subchannel *sch)
1039 {
1040         memset(&sch->config, 0, sizeof(sch->config));
1041         sch->config.csense = 1;
1042 }
1043
1044 static void io_subchannel_init_fields(struct subchannel *sch)
1045 {
1046         if (cio_is_console(sch->schid))
1047                 sch->opm = 0xff;
1048         else
1049                 sch->opm = chp_get_sch_opm(sch);
1050         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1051         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1052
1053         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1054                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1055                       sch->schib.pmcw.dev, sch->schid.ssid,
1056                       sch->schid.sch_no, sch->schib.pmcw.pim,
1057                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1058
1059         io_subchannel_init_config(sch);
1060 }
1061
1062 /*
1063  * Note: We always return 0 so that we bind to the device even on error.
1064  * This is needed so that our remove function is called on unregister.
1065  */
1066 static int io_subchannel_probe(struct subchannel *sch)
1067 {
1068         struct io_subchannel_private *io_priv;
1069         struct ccw_device *cdev;
1070         int rc;
1071
1072         if (cio_is_console(sch->schid)) {
1073                 rc = sysfs_create_group(&sch->dev.kobj,
1074                                         &io_subchannel_attr_group);
1075                 if (rc)
1076                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1077                                       "attributes for subchannel "
1078                                       "0.%x.%04x (rc=%d)\n",
1079                                       sch->schid.ssid, sch->schid.sch_no, rc);
1080                 /*
1081                  * The console subchannel already has an associated ccw_device.
1082                  * Throw the delayed uevent for the subchannel, register
1083                  * the ccw_device and exit.
1084                  */
1085                 dev_set_uevent_suppress(&sch->dev, 0);
1086                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1087                 cdev = sch_get_cdev(sch);
1088                 rc = ccw_device_add(cdev);
1089                 if (rc) {
1090                         /* Release online reference. */
1091                         put_device(&cdev->dev);
1092                         goto out_schedule;
1093                 }
1094                 if (atomic_dec_and_test(&ccw_device_init_count))
1095                         wake_up(&ccw_device_init_wq);
1096                 return 0;
1097         }
1098         io_subchannel_init_fields(sch);
1099         rc = cio_commit_config(sch);
1100         if (rc)
1101                 goto out_schedule;
1102         rc = sysfs_create_group(&sch->dev.kobj,
1103                                 &io_subchannel_attr_group);
1104         if (rc)
1105                 goto out_schedule;
1106         /* Allocate I/O subchannel private data. */
1107         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1108         if (!io_priv)
1109                 goto out_schedule;
1110
1111         set_io_private(sch, io_priv);
1112         css_schedule_eval(sch->schid);
1113         return 0;
1114
1115 out_schedule:
1116         spin_lock_irq(sch->lock);
1117         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1118         spin_unlock_irq(sch->lock);
1119         return 0;
1120 }
1121
1122 static int
1123 io_subchannel_remove (struct subchannel *sch)
1124 {
1125         struct io_subchannel_private *io_priv = to_io_private(sch);
1126         struct ccw_device *cdev;
1127
1128         cdev = sch_get_cdev(sch);
1129         if (!cdev)
1130                 goto out_free;
1131         io_subchannel_quiesce(sch);
1132         /* Set ccw device to not operational and drop reference. */
1133         spin_lock_irq(cdev->ccwlock);
1134         sch_set_cdev(sch, NULL);
1135         set_io_private(sch, NULL);
1136         cdev->private->state = DEV_STATE_NOT_OPER;
1137         spin_unlock_irq(cdev->ccwlock);
1138         ccw_device_unregister(cdev);
1139 out_free:
1140         kfree(io_priv);
1141         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1142         return 0;
1143 }
1144
1145 static void io_subchannel_verify(struct subchannel *sch)
1146 {
1147         struct ccw_device *cdev;
1148
1149         cdev = sch_get_cdev(sch);
1150         if (cdev)
1151                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1152 }
1153
1154 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1155 {
1156         struct ccw_device *cdev;
1157
1158         cdev = sch_get_cdev(sch);
1159         if (!cdev)
1160                 return;
1161         if (cio_update_schib(sch))
1162                 goto err;
1163         /* Check for I/O on path. */
1164         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1165                 goto out;
1166         if (cdev->private->state == DEV_STATE_ONLINE) {
1167                 ccw_device_kill_io(cdev);
1168                 goto out;
1169         }
1170         if (cio_clear(sch))
1171                 goto err;
1172 out:
1173         /* Trigger path verification. */
1174         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1175         return;
1176
1177 err:
1178         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1179 }
1180
1181 static int io_subchannel_chp_event(struct subchannel *sch,
1182                                    struct chp_link *link, int event)
1183 {
1184         struct ccw_device *cdev = sch_get_cdev(sch);
1185         int mask;
1186
1187         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1188         if (!mask)
1189                 return 0;
1190         switch (event) {
1191         case CHP_VARY_OFF:
1192                 sch->opm &= ~mask;
1193                 sch->lpm &= ~mask;
1194                 if (cdev)
1195                         cdev->private->path_gone_mask |= mask;
1196                 io_subchannel_terminate_path(sch, mask);
1197                 break;
1198         case CHP_VARY_ON:
1199                 sch->opm |= mask;
1200                 sch->lpm |= mask;
1201                 if (cdev)
1202                         cdev->private->path_new_mask |= mask;
1203                 io_subchannel_verify(sch);
1204                 break;
1205         case CHP_OFFLINE:
1206                 if (cio_update_schib(sch))
1207                         return -ENODEV;
1208                 if (cdev)
1209                         cdev->private->path_gone_mask |= mask;
1210                 io_subchannel_terminate_path(sch, mask);
1211                 break;
1212         case CHP_ONLINE:
1213                 if (cio_update_schib(sch))
1214                         return -ENODEV;
1215                 sch->lpm |= mask & sch->opm;
1216                 if (cdev)
1217                         cdev->private->path_new_mask |= mask;
1218                 io_subchannel_verify(sch);
1219                 break;
1220         }
1221         return 0;
1222 }
1223
1224 static void io_subchannel_quiesce(struct subchannel *sch)
1225 {
1226         struct ccw_device *cdev;
1227         int ret;
1228
1229         spin_lock_irq(sch->lock);
1230         cdev = sch_get_cdev(sch);
1231         if (cio_is_console(sch->schid))
1232                 goto out_unlock;
1233         if (!sch->schib.pmcw.ena)
1234                 goto out_unlock;
1235         ret = cio_disable_subchannel(sch);
1236         if (ret != -EBUSY)
1237                 goto out_unlock;
1238         if (cdev->handler)
1239                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1240         while (ret == -EBUSY) {
1241                 cdev->private->state = DEV_STATE_QUIESCE;
1242                 cdev->private->iretry = 255;
1243                 ret = ccw_device_cancel_halt_clear(cdev);
1244                 if (ret == -EBUSY) {
1245                         ccw_device_set_timeout(cdev, HZ/10);
1246                         spin_unlock_irq(sch->lock);
1247                         wait_event(cdev->private->wait_q,
1248                                    cdev->private->state != DEV_STATE_QUIESCE);
1249                         spin_lock_irq(sch->lock);
1250                 }
1251                 ret = cio_disable_subchannel(sch);
1252         }
1253 out_unlock:
1254         spin_unlock_irq(sch->lock);
1255 }
1256
1257 static void io_subchannel_shutdown(struct subchannel *sch)
1258 {
1259         io_subchannel_quiesce(sch);
1260 }
1261
1262 static int device_is_disconnected(struct ccw_device *cdev)
1263 {
1264         if (!cdev)
1265                 return 0;
1266         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1267                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1268 }
1269
1270 static int recovery_check(struct device *dev, void *data)
1271 {
1272         struct ccw_device *cdev = to_ccwdev(dev);
1273         int *redo = data;
1274
1275         spin_lock_irq(cdev->ccwlock);
1276         switch (cdev->private->state) {
1277         case DEV_STATE_DISCONNECTED:
1278                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1279                               cdev->private->dev_id.ssid,
1280                               cdev->private->dev_id.devno);
1281                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1282                 *redo = 1;
1283                 break;
1284         case DEV_STATE_DISCONNECTED_SENSE_ID:
1285                 *redo = 1;
1286                 break;
1287         }
1288         spin_unlock_irq(cdev->ccwlock);
1289
1290         return 0;
1291 }
1292
1293 static void recovery_work_func(struct work_struct *unused)
1294 {
1295         int redo = 0;
1296
1297         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1298         if (redo) {
1299                 spin_lock_irq(&recovery_lock);
1300                 if (!timer_pending(&recovery_timer)) {
1301                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1302                                 recovery_phase++;
1303                         mod_timer(&recovery_timer, jiffies +
1304                                   recovery_delay[recovery_phase] * HZ);
1305                 }
1306                 spin_unlock_irq(&recovery_lock);
1307         } else
1308                 CIO_MSG_EVENT(4, "recovery: end\n");
1309 }
1310
1311 static DECLARE_WORK(recovery_work, recovery_work_func);
1312
1313 static void recovery_func(unsigned long data)
1314 {
1315         /*
1316          * We can't do our recovery in softirq context and it's not
1317          * performance critical, so we schedule it.
1318          */
1319         schedule_work(&recovery_work);
1320 }
1321
1322 static void ccw_device_schedule_recovery(void)
1323 {
1324         unsigned long flags;
1325
1326         CIO_MSG_EVENT(4, "recovery: schedule\n");
1327         spin_lock_irqsave(&recovery_lock, flags);
1328         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1329                 recovery_phase = 0;
1330                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1331         }
1332         spin_unlock_irqrestore(&recovery_lock, flags);
1333 }
1334
1335 static int purge_fn(struct device *dev, void *data)
1336 {
1337         struct ccw_device *cdev = to_ccwdev(dev);
1338         struct ccw_dev_id *id = &cdev->private->dev_id;
1339
1340         spin_lock_irq(cdev->ccwlock);
1341         if (is_blacklisted(id->ssid, id->devno) &&
1342             (cdev->private->state == DEV_STATE_OFFLINE) &&
1343             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1344                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1345                               id->devno);
1346                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1347                 atomic_set(&cdev->private->onoff, 0);
1348         }
1349         spin_unlock_irq(cdev->ccwlock);
1350         /* Abort loop in case of pending signal. */
1351         if (signal_pending(current))
1352                 return -EINTR;
1353
1354         return 0;
1355 }
1356
1357 /**
1358  * ccw_purge_blacklisted - purge unused, blacklisted devices
1359  *
1360  * Unregister all ccw devices that are offline and on the blacklist.
1361  */
1362 int ccw_purge_blacklisted(void)
1363 {
1364         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1365         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1366         return 0;
1367 }
1368
1369 void ccw_device_set_disconnected(struct ccw_device *cdev)
1370 {
1371         if (!cdev)
1372                 return;
1373         ccw_device_set_timeout(cdev, 0);
1374         cdev->private->flags.fake_irb = 0;
1375         cdev->private->state = DEV_STATE_DISCONNECTED;
1376         if (cdev->online)
1377                 ccw_device_schedule_recovery();
1378 }
1379
1380 void ccw_device_set_notoper(struct ccw_device *cdev)
1381 {
1382         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1383
1384         CIO_TRACE_EVENT(2, "notoper");
1385         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1386         ccw_device_set_timeout(cdev, 0);
1387         cio_disable_subchannel(sch);
1388         cdev->private->state = DEV_STATE_NOT_OPER;
1389 }
1390
1391 enum io_sch_action {
1392         IO_SCH_UNREG,
1393         IO_SCH_ORPH_UNREG,
1394         IO_SCH_ATTACH,
1395         IO_SCH_UNREG_ATTACH,
1396         IO_SCH_ORPH_ATTACH,
1397         IO_SCH_REPROBE,
1398         IO_SCH_VERIFY,
1399         IO_SCH_DISC,
1400         IO_SCH_NOP,
1401 };
1402
1403 static enum io_sch_action sch_get_action(struct subchannel *sch)
1404 {
1405         struct ccw_device *cdev;
1406
1407         cdev = sch_get_cdev(sch);
1408         if (cio_update_schib(sch)) {
1409                 /* Not operational. */
1410                 if (!cdev)
1411                         return IO_SCH_UNREG;
1412                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1413                         return IO_SCH_UNREG;
1414                 return IO_SCH_ORPH_UNREG;
1415         }
1416         /* Operational. */
1417         if (!cdev)
1418                 return IO_SCH_ATTACH;
1419         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1420                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1421                         return IO_SCH_UNREG_ATTACH;
1422                 return IO_SCH_ORPH_ATTACH;
1423         }
1424         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1425                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1426                         return IO_SCH_UNREG;
1427                 return IO_SCH_DISC;
1428         }
1429         if (device_is_disconnected(cdev))
1430                 return IO_SCH_REPROBE;
1431         if (cdev->online && !cdev->private->flags.resuming)
1432                 return IO_SCH_VERIFY;
1433         if (cdev->private->state == DEV_STATE_NOT_OPER)
1434                 return IO_SCH_UNREG_ATTACH;
1435         return IO_SCH_NOP;
1436 }
1437
1438 /**
1439  * io_subchannel_sch_event - process subchannel event
1440  * @sch: subchannel
1441  * @process: non-zero if function is called in process context
1442  *
1443  * An unspecified event occurred for this subchannel. Adjust data according
1444  * to the current operational state of the subchannel and device. Return
1445  * zero when the event has been handled sufficiently or -EAGAIN when this
1446  * function should be called again in process context.
1447  */
1448 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1449 {
1450         unsigned long flags;
1451         struct ccw_device *cdev;
1452         struct ccw_dev_id dev_id;
1453         enum io_sch_action action;
1454         int rc = -EAGAIN;
1455
1456         spin_lock_irqsave(sch->lock, flags);
1457         if (!device_is_registered(&sch->dev))
1458                 goto out_unlock;
1459         if (work_pending(&sch->todo_work))
1460                 goto out_unlock;
1461         cdev = sch_get_cdev(sch);
1462         if (cdev && work_pending(&cdev->private->todo_work))
1463                 goto out_unlock;
1464         action = sch_get_action(sch);
1465         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1466                       sch->schid.ssid, sch->schid.sch_no, process,
1467                       action);
1468         /* Perform immediate actions while holding the lock. */
1469         switch (action) {
1470         case IO_SCH_REPROBE:
1471                 /* Trigger device recognition. */
1472                 ccw_device_trigger_reprobe(cdev);
1473                 rc = 0;
1474                 goto out_unlock;
1475         case IO_SCH_VERIFY:
1476                 /* Trigger path verification. */
1477                 io_subchannel_verify(sch);
1478                 rc = 0;
1479                 goto out_unlock;
1480         case IO_SCH_DISC:
1481                 ccw_device_set_disconnected(cdev);
1482                 rc = 0;
1483                 goto out_unlock;
1484         case IO_SCH_ORPH_UNREG:
1485         case IO_SCH_ORPH_ATTACH:
1486                 ccw_device_set_disconnected(cdev);
1487                 break;
1488         case IO_SCH_UNREG_ATTACH:
1489         case IO_SCH_UNREG:
1490                 if (!cdev)
1491                         break;
1492                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1493                         /*
1494                          * Note: delayed work triggered by this event
1495                          * and repeated calls to sch_event are synchronized
1496                          * by the above check for work_pending(cdev).
1497                          */
1498                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1499                 } else
1500                         ccw_device_set_notoper(cdev);
1501                 break;
1502         case IO_SCH_NOP:
1503                 rc = 0;
1504                 goto out_unlock;
1505         default:
1506                 break;
1507         }
1508         spin_unlock_irqrestore(sch->lock, flags);
1509         /* All other actions require process context. */
1510         if (!process)
1511                 goto out;
1512         /* Handle attached ccw device. */
1513         switch (action) {
1514         case IO_SCH_ORPH_UNREG:
1515         case IO_SCH_ORPH_ATTACH:
1516                 /* Move ccw device to orphanage. */
1517                 rc = ccw_device_move_to_orph(cdev);
1518                 if (rc)
1519                         goto out;
1520                 break;
1521         case IO_SCH_UNREG_ATTACH:
1522                 spin_lock_irqsave(sch->lock, flags);
1523                 if (cdev->private->flags.resuming) {
1524                         /* Device will be handled later. */
1525                         rc = 0;
1526                         goto out_unlock;
1527                 }
1528                 sch_set_cdev(sch, NULL);
1529                 spin_unlock_irqrestore(sch->lock, flags);
1530                 /* Unregister ccw device. */
1531                 ccw_device_unregister(cdev);
1532                 break;
1533         default:
1534                 break;
1535         }
1536         /* Handle subchannel. */
1537         switch (action) {
1538         case IO_SCH_ORPH_UNREG:
1539         case IO_SCH_UNREG:
1540                 if (!cdev || !cdev->private->flags.resuming)
1541                         css_sch_device_unregister(sch);
1542                 break;
1543         case IO_SCH_ORPH_ATTACH:
1544         case IO_SCH_UNREG_ATTACH:
1545         case IO_SCH_ATTACH:
1546                 dev_id.ssid = sch->schid.ssid;
1547                 dev_id.devno = sch->schib.pmcw.dev;
1548                 cdev = get_ccwdev_by_dev_id(&dev_id);
1549                 if (!cdev) {
1550                         sch_create_and_recog_new_device(sch);
1551                         break;
1552                 }
1553                 rc = ccw_device_move_to_sch(cdev, sch);
1554                 if (rc) {
1555                         /* Release reference from get_ccwdev_by_dev_id() */
1556                         put_device(&cdev->dev);
1557                         goto out;
1558                 }
1559                 spin_lock_irqsave(sch->lock, flags);
1560                 ccw_device_trigger_reprobe(cdev);
1561                 spin_unlock_irqrestore(sch->lock, flags);
1562                 /* Release reference from get_ccwdev_by_dev_id() */
1563                 put_device(&cdev->dev);
1564                 break;
1565         default:
1566                 break;
1567         }
1568         return 0;
1569
1570 out_unlock:
1571         spin_unlock_irqrestore(sch->lock, flags);
1572 out:
1573         return rc;
1574 }
1575
1576 static void ccw_device_set_int_class(struct ccw_device *cdev)
1577 {
1578         struct ccw_driver *cdrv = cdev->drv;
1579
1580         /* Note: we interpret class 0 in this context as an uninitialized
1581          * field since it translates to a non-I/O interrupt class. */
1582         if (cdrv->int_class != 0)
1583                 cdev->private->int_class = cdrv->int_class;
1584         else
1585                 cdev->private->int_class = IRQIO_CIO;
1586 }
1587
1588 #ifdef CONFIG_CCW_CONSOLE
1589 int __init ccw_device_enable_console(struct ccw_device *cdev)
1590 {
1591         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1592         int rc;
1593
1594         if (!cdev->drv || !cdev->handler)
1595                 return -EINVAL;
1596
1597         io_subchannel_init_fields(sch);
1598         rc = cio_commit_config(sch);
1599         if (rc)
1600                 return rc;
1601         sch->driver = &io_subchannel_driver;
1602         io_subchannel_recog(cdev, sch);
1603         /* Now wait for the async. recognition to come to an end. */
1604         spin_lock_irq(cdev->ccwlock);
1605         while (!dev_fsm_final_state(cdev))
1606                 ccw_device_wait_idle(cdev);
1607
1608         /* Hold on to an extra reference while device is online. */
1609         get_device(&cdev->dev);
1610         rc = ccw_device_online(cdev);
1611         if (rc)
1612                 goto out_unlock;
1613
1614         while (!dev_fsm_final_state(cdev))
1615                 ccw_device_wait_idle(cdev);
1616
1617         if (cdev->private->state == DEV_STATE_ONLINE)
1618                 cdev->online = 1;
1619         else
1620                 rc = -EIO;
1621 out_unlock:
1622         spin_unlock_irq(cdev->ccwlock);
1623         if (rc) /* Give up online reference since onlining failed. */
1624                 put_device(&cdev->dev);
1625         return rc;
1626 }
1627
1628 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1629 {
1630         struct io_subchannel_private *io_priv;
1631         struct ccw_device *cdev;
1632         struct subchannel *sch;
1633
1634         sch = cio_probe_console();
1635         if (IS_ERR(sch))
1636                 return ERR_CAST(sch);
1637
1638         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1639         if (!io_priv) {
1640                 put_device(&sch->dev);
1641                 return ERR_PTR(-ENOMEM);
1642         }
1643         set_io_private(sch, io_priv);
1644         cdev = io_subchannel_create_ccwdev(sch);
1645         if (IS_ERR(cdev)) {
1646                 put_device(&sch->dev);
1647                 kfree(io_priv);
1648                 return cdev;
1649         }
1650         cdev->drv = drv;
1651         ccw_device_set_int_class(cdev);
1652         return cdev;
1653 }
1654
1655 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1656 {
1657         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1658         struct io_subchannel_private *io_priv = to_io_private(sch);
1659
1660         set_io_private(sch, NULL);
1661         put_device(&sch->dev);
1662         put_device(&cdev->dev);
1663         kfree(io_priv);
1664 }
1665
1666 /**
1667  * ccw_device_wait_idle() - busy wait for device to become idle
1668  * @cdev: ccw device
1669  *
1670  * Poll until activity control is zero, that is, no function or data
1671  * transfer is pending/active.
1672  * Called with device lock being held.
1673  */
1674 void ccw_device_wait_idle(struct ccw_device *cdev)
1675 {
1676         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1677
1678         while (1) {
1679                 cio_tsch(sch);
1680                 if (sch->schib.scsw.cmd.actl == 0)
1681                         break;
1682                 udelay_simple(100);
1683         }
1684 }
1685
1686 static int ccw_device_pm_restore(struct device *dev);
1687
1688 int ccw_device_force_console(struct ccw_device *cdev)
1689 {
1690         return ccw_device_pm_restore(&cdev->dev);
1691 }
1692 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1693 #endif
1694
1695 /*
1696  * get ccw_device matching the busid, but only if owned by cdrv
1697  */
1698 static int
1699 __ccwdev_check_busid(struct device *dev, void *id)
1700 {
1701         char *bus_id;
1702
1703         bus_id = id;
1704
1705         return (strcmp(bus_id, dev_name(dev)) == 0);
1706 }
1707
1708
1709 /**
1710  * get_ccwdev_by_busid() - obtain device from a bus id
1711  * @cdrv: driver the device is owned by
1712  * @bus_id: bus id of the device to be searched
1713  *
1714  * This function searches all devices owned by @cdrv for a device with a bus
1715  * id matching @bus_id.
1716  * Returns:
1717  *  If a match is found, its reference count of the found device is increased
1718  *  and it is returned; else %NULL is returned.
1719  */
1720 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1721                                        const char *bus_id)
1722 {
1723         struct device *dev;
1724
1725         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1726                                  __ccwdev_check_busid);
1727
1728         return dev ? to_ccwdev(dev) : NULL;
1729 }
1730
1731 /************************** device driver handling ************************/
1732
1733 /* This is the implementation of the ccw_driver class. The probe, remove
1734  * and release methods are initially very similar to the device_driver
1735  * implementations, with the difference that they have ccw_device
1736  * arguments.
1737  *
1738  * A ccw driver also contains the information that is needed for
1739  * device matching.
1740  */
1741 static int
1742 ccw_device_probe (struct device *dev)
1743 {
1744         struct ccw_device *cdev = to_ccwdev(dev);
1745         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1746         int ret;
1747
1748         cdev->drv = cdrv; /* to let the driver call _set_online */
1749         ccw_device_set_int_class(cdev);
1750         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1751         if (ret) {
1752                 cdev->drv = NULL;
1753                 cdev->private->int_class = IRQIO_CIO;
1754                 return ret;
1755         }
1756
1757         return 0;
1758 }
1759
1760 static int ccw_device_remove(struct device *dev)
1761 {
1762         struct ccw_device *cdev = to_ccwdev(dev);
1763         struct ccw_driver *cdrv = cdev->drv;
1764         int ret;
1765
1766         if (cdrv->remove)
1767                 cdrv->remove(cdev);
1768
1769         spin_lock_irq(cdev->ccwlock);
1770         if (cdev->online) {
1771                 cdev->online = 0;
1772                 ret = ccw_device_offline(cdev);
1773                 spin_unlock_irq(cdev->ccwlock);
1774                 if (ret == 0)
1775                         wait_event(cdev->private->wait_q,
1776                                    dev_fsm_final_state(cdev));
1777                 else
1778                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1779                                       "device 0.%x.%04x\n",
1780                                       ret, cdev->private->dev_id.ssid,
1781                                       cdev->private->dev_id.devno);
1782                 /* Give up reference obtained in ccw_device_set_online(). */
1783                 put_device(&cdev->dev);
1784                 spin_lock_irq(cdev->ccwlock);
1785         }
1786         ccw_device_set_timeout(cdev, 0);
1787         cdev->drv = NULL;
1788         cdev->private->int_class = IRQIO_CIO;
1789         spin_unlock_irq(cdev->ccwlock);
1790         return 0;
1791 }
1792
1793 static void ccw_device_shutdown(struct device *dev)
1794 {
1795         struct ccw_device *cdev;
1796
1797         cdev = to_ccwdev(dev);
1798         if (cdev->drv && cdev->drv->shutdown)
1799                 cdev->drv->shutdown(cdev);
1800         disable_cmf(cdev);
1801 }
1802
1803 static int ccw_device_pm_prepare(struct device *dev)
1804 {
1805         struct ccw_device *cdev = to_ccwdev(dev);
1806
1807         if (work_pending(&cdev->private->todo_work))
1808                 return -EAGAIN;
1809         /* Fail while device is being set online/offline. */
1810         if (atomic_read(&cdev->private->onoff))
1811                 return -EAGAIN;
1812
1813         if (cdev->online && cdev->drv && cdev->drv->prepare)
1814                 return cdev->drv->prepare(cdev);
1815
1816         return 0;
1817 }
1818
1819 static void ccw_device_pm_complete(struct device *dev)
1820 {
1821         struct ccw_device *cdev = to_ccwdev(dev);
1822
1823         if (cdev->online && cdev->drv && cdev->drv->complete)
1824                 cdev->drv->complete(cdev);
1825 }
1826
1827 static int ccw_device_pm_freeze(struct device *dev)
1828 {
1829         struct ccw_device *cdev = to_ccwdev(dev);
1830         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1831         int ret, cm_enabled;
1832
1833         /* Fail suspend while device is in transistional state. */
1834         if (!dev_fsm_final_state(cdev))
1835                 return -EAGAIN;
1836         if (!cdev->online)
1837                 return 0;
1838         if (cdev->drv && cdev->drv->freeze) {
1839                 ret = cdev->drv->freeze(cdev);
1840                 if (ret)
1841                         return ret;
1842         }
1843
1844         spin_lock_irq(sch->lock);
1845         cm_enabled = cdev->private->cmb != NULL;
1846         spin_unlock_irq(sch->lock);
1847         if (cm_enabled) {
1848                 /* Don't have the css write on memory. */
1849                 ret = ccw_set_cmf(cdev, 0);
1850                 if (ret)
1851                         return ret;
1852         }
1853         /* From here on, disallow device driver I/O. */
1854         spin_lock_irq(sch->lock);
1855         ret = cio_disable_subchannel(sch);
1856         spin_unlock_irq(sch->lock);
1857
1858         return ret;
1859 }
1860
1861 static int ccw_device_pm_thaw(struct device *dev)
1862 {
1863         struct ccw_device *cdev = to_ccwdev(dev);
1864         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1865         int ret, cm_enabled;
1866
1867         if (!cdev->online)
1868                 return 0;
1869
1870         spin_lock_irq(sch->lock);
1871         /* Allow device driver I/O again. */
1872         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1873         cm_enabled = cdev->private->cmb != NULL;
1874         spin_unlock_irq(sch->lock);
1875         if (ret)
1876                 return ret;
1877
1878         if (cm_enabled) {
1879                 ret = ccw_set_cmf(cdev, 1);
1880                 if (ret)
1881                         return ret;
1882         }
1883
1884         if (cdev->drv && cdev->drv->thaw)
1885                 ret = cdev->drv->thaw(cdev);
1886
1887         return ret;
1888 }
1889
1890 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1891 {
1892         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1893
1894         spin_lock_irq(sch->lock);
1895         if (cio_is_console(sch->schid)) {
1896                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1897                 goto out_unlock;
1898         }
1899         /*
1900          * While we were sleeping, devices may have gone or become
1901          * available again. Kick re-detection.
1902          */
1903         cdev->private->flags.resuming = 1;
1904         cdev->private->path_new_mask = LPM_ANYPATH;
1905         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1906         spin_unlock_irq(sch->lock);
1907         css_wait_for_slow_path();
1908
1909         /* cdev may have been moved to a different subchannel. */
1910         sch = to_subchannel(cdev->dev.parent);
1911         spin_lock_irq(sch->lock);
1912         if (cdev->private->state != DEV_STATE_ONLINE &&
1913             cdev->private->state != DEV_STATE_OFFLINE)
1914                 goto out_unlock;
1915
1916         ccw_device_recognition(cdev);
1917         spin_unlock_irq(sch->lock);
1918         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1919                    cdev->private->state == DEV_STATE_DISCONNECTED);
1920         spin_lock_irq(sch->lock);
1921
1922 out_unlock:
1923         cdev->private->flags.resuming = 0;
1924         spin_unlock_irq(sch->lock);
1925 }
1926
1927 static int resume_handle_boxed(struct ccw_device *cdev)
1928 {
1929         cdev->private->state = DEV_STATE_BOXED;
1930         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1931                 return 0;
1932         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1933         return -ENODEV;
1934 }
1935
1936 static int resume_handle_disc(struct ccw_device *cdev)
1937 {
1938         cdev->private->state = DEV_STATE_DISCONNECTED;
1939         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1940                 return 0;
1941         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1942         return -ENODEV;
1943 }
1944
1945 static int ccw_device_pm_restore(struct device *dev)
1946 {
1947         struct ccw_device *cdev = to_ccwdev(dev);
1948         struct subchannel *sch;
1949         int ret = 0;
1950
1951         __ccw_device_pm_restore(cdev);
1952         sch = to_subchannel(cdev->dev.parent);
1953         spin_lock_irq(sch->lock);
1954         if (cio_is_console(sch->schid))
1955                 goto out_restore;
1956
1957         /* check recognition results */
1958         switch (cdev->private->state) {
1959         case DEV_STATE_OFFLINE:
1960         case DEV_STATE_ONLINE:
1961                 cdev->private->flags.donotify = 0;
1962                 break;
1963         case DEV_STATE_BOXED:
1964                 ret = resume_handle_boxed(cdev);
1965                 if (ret)
1966                         goto out_unlock;
1967                 goto out_restore;
1968         default:
1969                 ret = resume_handle_disc(cdev);
1970                 if (ret)
1971                         goto out_unlock;
1972                 goto out_restore;
1973         }
1974         /* check if the device type has changed */
1975         if (!ccw_device_test_sense_data(cdev)) {
1976                 ccw_device_update_sense_data(cdev);
1977                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1978                 ret = -ENODEV;
1979                 goto out_unlock;
1980         }
1981         if (!cdev->online)
1982                 goto out_unlock;
1983
1984         if (ccw_device_online(cdev)) {
1985                 ret = resume_handle_disc(cdev);
1986                 if (ret)
1987                         goto out_unlock;
1988                 goto out_restore;
1989         }
1990         spin_unlock_irq(sch->lock);
1991         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1992         spin_lock_irq(sch->lock);
1993
1994         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1995                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1996                 ret = -ENODEV;
1997                 goto out_unlock;
1998         }
1999
2000         /* reenable cmf, if needed */
2001         if (cdev->private->cmb) {
2002                 spin_unlock_irq(sch->lock);
2003                 ret = ccw_set_cmf(cdev, 1);
2004                 spin_lock_irq(sch->lock);
2005                 if (ret) {
2006                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2007                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
2008                                       cdev->private->dev_id.devno, ret);
2009                         ret = 0;
2010                 }
2011         }
2012
2013 out_restore:
2014         spin_unlock_irq(sch->lock);
2015         if (cdev->online && cdev->drv && cdev->drv->restore)
2016                 ret = cdev->drv->restore(cdev);
2017         return ret;
2018
2019 out_unlock:
2020         spin_unlock_irq(sch->lock);
2021         return ret;
2022 }
2023
2024 static const struct dev_pm_ops ccw_pm_ops = {
2025         .prepare = ccw_device_pm_prepare,
2026         .complete = ccw_device_pm_complete,
2027         .freeze = ccw_device_pm_freeze,
2028         .thaw = ccw_device_pm_thaw,
2029         .restore = ccw_device_pm_restore,
2030 };
2031
2032 static struct bus_type ccw_bus_type = {
2033         .name   = "ccw",
2034         .match  = ccw_bus_match,
2035         .uevent = ccw_uevent,
2036         .probe  = ccw_device_probe,
2037         .remove = ccw_device_remove,
2038         .shutdown = ccw_device_shutdown,
2039         .pm = &ccw_pm_ops,
2040 };
2041
2042 /**
2043  * ccw_driver_register() - register a ccw driver
2044  * @cdriver: driver to be registered
2045  *
2046  * This function is mainly a wrapper around driver_register().
2047  * Returns:
2048  *   %0 on success and a negative error value on failure.
2049  */
2050 int ccw_driver_register(struct ccw_driver *cdriver)
2051 {
2052         struct device_driver *drv = &cdriver->driver;
2053
2054         drv->bus = &ccw_bus_type;
2055
2056         return driver_register(drv);
2057 }
2058
2059 /**
2060  * ccw_driver_unregister() - deregister a ccw driver
2061  * @cdriver: driver to be deregistered
2062  *
2063  * This function is mainly a wrapper around driver_unregister().
2064  */
2065 void ccw_driver_unregister(struct ccw_driver *cdriver)
2066 {
2067         driver_unregister(&cdriver->driver);
2068 }
2069
2070 static void ccw_device_todo(struct work_struct *work)
2071 {
2072         struct ccw_device_private *priv;
2073         struct ccw_device *cdev;
2074         struct subchannel *sch;
2075         enum cdev_todo todo;
2076
2077         priv = container_of(work, struct ccw_device_private, todo_work);
2078         cdev = priv->cdev;
2079         sch = to_subchannel(cdev->dev.parent);
2080         /* Find out todo. */
2081         spin_lock_irq(cdev->ccwlock);
2082         todo = priv->todo;
2083         priv->todo = CDEV_TODO_NOTHING;
2084         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2085                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2086         spin_unlock_irq(cdev->ccwlock);
2087         /* Perform todo. */
2088         switch (todo) {
2089         case CDEV_TODO_ENABLE_CMF:
2090                 cmf_reenable(cdev);
2091                 break;
2092         case CDEV_TODO_REBIND:
2093                 ccw_device_do_unbind_bind(cdev);
2094                 break;
2095         case CDEV_TODO_REGISTER:
2096                 io_subchannel_register(cdev);
2097                 break;
2098         case CDEV_TODO_UNREG_EVAL:
2099                 if (!sch_is_pseudo_sch(sch))
2100                         css_schedule_eval(sch->schid);
2101                 /* fall-through */
2102         case CDEV_TODO_UNREG:
2103                 if (sch_is_pseudo_sch(sch))
2104                         ccw_device_unregister(cdev);
2105                 else
2106                         ccw_device_call_sch_unregister(cdev);
2107                 break;
2108         default:
2109                 break;
2110         }
2111         /* Release workqueue ref. */
2112         put_device(&cdev->dev);
2113 }
2114
2115 /**
2116  * ccw_device_sched_todo - schedule ccw device operation
2117  * @cdev: ccw device
2118  * @todo: todo
2119  *
2120  * Schedule the operation identified by @todo to be performed on the slow path
2121  * workqueue. Do nothing if another operation with higher priority is already
2122  * scheduled. Needs to be called with ccwdev lock held.
2123  */
2124 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2125 {
2126         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2127                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2128                       todo);
2129         if (cdev->private->todo >= todo)
2130                 return;
2131         cdev->private->todo = todo;
2132         /* Get workqueue ref. */
2133         if (!get_device(&cdev->dev))
2134                 return;
2135         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2136                 /* Already queued, release workqueue ref. */
2137                 put_device(&cdev->dev);
2138         }
2139 }
2140
2141 /**
2142  * ccw_device_siosl() - initiate logging
2143  * @cdev: ccw device
2144  *
2145  * This function is used to invoke model-dependent logging within the channel
2146  * subsystem.
2147  */
2148 int ccw_device_siosl(struct ccw_device *cdev)
2149 {
2150         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2151
2152         return chsc_siosl(sch->schid);
2153 }
2154 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2155
2156 MODULE_LICENSE("GPL");
2157 EXPORT_SYMBOL(ccw_device_set_online);
2158 EXPORT_SYMBOL(ccw_device_set_offline);
2159 EXPORT_SYMBOL(ccw_driver_register);
2160 EXPORT_SYMBOL(ccw_driver_unregister);
2161 EXPORT_SYMBOL(get_ccwdev_by_busid);