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  * License: GPL
  10  */
  11
  12 #define KMSG_COMPONENT "cio"
  13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  14
  15 #include <linux/export.h>
  16 #include <linux/init.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/errno.h>
  19 #include <linux/err.h>
  20 #include <linux/slab.h>
  21 #include <linux/list.h>
  22 #include <linux/device.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/delay.h>
  25 #include <linux/timer.h>
  26 #include <linux/kernel_stat.h>
  27 #include <linux/sched/signal.h>
  28
  29 #include <asm/ccwdev.h>
  30 #include <asm/cio.h>
  31 #include <asm/param.h>          /* HZ */
  32 #include <asm/cmb.h>
  33 #include <asm/isc.h>
  34
  35 #include "chp.h"
  36 #include "cio.h"
  37 #include "cio_debug.h"
  38 #include "css.h"
  39 #include "device.h"
  40 #include "ioasm.h"
  41 #include "io_sch.h"
  42 #include "blacklist.h"
  43 #include "chsc.h"
  44
  45 static struct timer_list recovery_timer;
  46 static DEFINE_SPINLOCK(recovery_lock);
  47 static int recovery_phase;
  48 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  49
  50 static atomic_t ccw_device_init_count = ATOMIC_INIT(0);
  51 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq);
  52 static struct bus_type ccw_bus_type;
  53
  54 /******************* bus type handling ***********************/
  55
  56 /* The Linux driver model distinguishes between a bus type and
  57  * the bus itself. Of course we only have one channel
  58  * subsystem driver and one channel system per machine, but
  59  * we still use the abstraction. T.R. says it's a good idea. */
  60 static int
  61 ccw_bus_match (struct device * dev, struct device_driver * drv)
  62 {
  63         struct ccw_device *cdev = to_ccwdev(dev);
  64         struct ccw_driver *cdrv = to_ccwdrv(drv);
  65         const struct ccw_device_id *ids = cdrv->ids, *found;
  66
  67         if (!ids)
  68                 return 0;
  69
  70         found = ccw_device_id_match(ids, &cdev->id);
  71         if (!found)
  72                 return 0;
  73
  74         cdev->id.driver_info = found->driver_info;
  75
  76         return 1;
  77 }
  78
  79 /* Store modalias string delimited by prefix/suffix string into buffer with
  80  * specified size. Return length of resulting string (excluding trailing '\0')
  81  * even if string doesn't fit buffer (snprintf semantics). */
  82 static int snprint_alias(char *buf, size_t size,
  83                          struct ccw_device_id *id, const char *suffix)
  84 {
  85         int len;
  86
  87         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  88         if (len > size)
  89                 return len;
  90         buf += len;
  91         size -= len;
  92
  93         if (id->dev_type != 0)
  94                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  95                                 id->dev_model, suffix);
  96         else
  97                 len += snprintf(buf, size, "dtdm%s", suffix);
  98
  99         return len;
 100 }
 101
 102 /* Set up environment variables for ccw device uevent. Return 0 on success,
 103  * non-zero otherwise. */
 104 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
 105 {
 106         struct ccw_device *cdev = to_ccwdev(dev);
 107         struct ccw_device_id *id = &(cdev->id);
 108         int ret;
 109         char modalias_buf[30];
 110
 111         /* CU_TYPE= */
 112         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 113         if (ret)
 114                 return ret;
 115
 116         /* CU_MODEL= */
 117         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 118         if (ret)
 119                 return ret;
 120
 121         /* The next two can be zero, that's ok for us */
 122         /* DEV_TYPE= */
 123         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 124         if (ret)
 125                 return ret;
 126
 127         /* DEV_MODEL= */
 128         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 129         if (ret)
 130                 return ret;
 131
 132         /* MODALIAS=  */
 133         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 134         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 135         return ret;
 136 }
 137
 138 static void io_subchannel_irq(struct subchannel *);
 139 static int io_subchannel_probe(struct subchannel *);
 140 static int io_subchannel_remove(struct subchannel *);
 141 static void io_subchannel_shutdown(struct subchannel *);
 142 static int io_subchannel_sch_event(struct subchannel *, int);
 143 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 144                                    int);
 145 static void recovery_func(unsigned long data);
 146
 147 static struct css_device_id io_subchannel_ids[] = {
 148         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 149         { /* end of list */ },
 150 };
 151
 152 static int io_subchannel_prepare(struct subchannel *sch)
 153 {
 154         struct ccw_device *cdev;
 155         /*
 156          * Don't allow suspend while a ccw device registration
 157          * is still outstanding.
 158          */
 159         cdev = sch_get_cdev(sch);
 160         if (cdev && !device_is_registered(&cdev->dev))
 161                 return -EAGAIN;
 162         return 0;
 163 }
 164
 165 static int io_subchannel_settle(void)
 166 {
 167         int ret;
 168
 169         ret = wait_event_interruptible(ccw_device_init_wq,
 170                                 atomic_read(&ccw_device_init_count) == 0);
 171         if (ret)
 172                 return -EINTR;
 173         flush_workqueue(cio_work_q);
 174         return 0;
 175 }
 176
 177 static struct css_driver io_subchannel_driver = {
 178         .drv = {
 179                 .owner = THIS_MODULE,
 180                 .name = "io_subchannel",
 181         },
 182         .subchannel_type = io_subchannel_ids,
 183         .irq = io_subchannel_irq,
 184         .sch_event = io_subchannel_sch_event,
 185         .chp_event = io_subchannel_chp_event,
 186         .probe = io_subchannel_probe,
 187         .remove = io_subchannel_remove,
 188         .shutdown = io_subchannel_shutdown,
 189         .prepare = io_subchannel_prepare,
 190         .settle = io_subchannel_settle,
 191 };
 192
 193 int __init io_subchannel_init(void)
 194 {
 195         int ret;
 196
 197         setup_timer(&recovery_timer, recovery_func, 0);
 198         ret = bus_register(&ccw_bus_type);
 199         if (ret)
 200                 return ret;
 201         ret = css_driver_register(&io_subchannel_driver);
 202         if (ret)
 203                 bus_unregister(&ccw_bus_type);
 204
 205         return ret;
 206 }
 207
 208
 209 /************************ device handling **************************/
 210
 211 /*
 212  * A ccw_device has some interfaces in sysfs in addition to the
 213  * standard ones.
 214  * The following entries are designed to export the information which
 215  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 216  * are obvious, so they don't have an entry :)
 217  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 218  */
 219 static ssize_t
 220 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 221 {
 222         struct subchannel *sch = to_subchannel(dev);
 223         struct chsc_ssd_info *ssd = &sch->ssd_info;
 224         ssize_t ret = 0;
 225         int chp;
 226         int mask;
 227
 228         for (chp = 0; chp < 8; chp++) {
 229                 mask = 0x80 >> chp;
 230                 if (ssd->path_mask & mask)
 231                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 232                 else
 233                         ret += sprintf(buf + ret, "00 ");
 234         }
 235         ret += sprintf (buf+ret, "\n");
 236         return min((ssize_t)PAGE_SIZE, ret);
 237 }
 238
 239 static ssize_t
 240 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 241 {
 242         struct subchannel *sch = to_subchannel(dev);
 243         struct pmcw *pmcw = &sch->schib.pmcw;
 244
 245         return sprintf (buf, "%02x %02x %02x\n",
 246                         pmcw->pim, pmcw->pam, pmcw->pom);
 247 }
 248
 249 static ssize_t
 250 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 251 {
 252         struct ccw_device *cdev = to_ccwdev(dev);
 253         struct ccw_device_id *id = &(cdev->id);
 254
 255         if (id->dev_type != 0)
 256                 return sprintf(buf, "%04x/%02x\n",
 257                                 id->dev_type, id->dev_model);
 258         else
 259                 return sprintf(buf, "n/a\n");
 260 }
 261
 262 static ssize_t
 263 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 264 {
 265         struct ccw_device *cdev = to_ccwdev(dev);
 266         struct ccw_device_id *id = &(cdev->id);
 267
 268         return sprintf(buf, "%04x/%02x\n",
 269                        id->cu_type, id->cu_model);
 270 }
 271
 272 static ssize_t
 273 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 274 {
 275         struct ccw_device *cdev = to_ccwdev(dev);
 276         struct ccw_device_id *id = &(cdev->id);
 277         int len;
 278
 279         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 280
 281         return len > PAGE_SIZE ? PAGE_SIZE : len;
 282 }
 283
 284 static ssize_t
 285 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 286 {
 287         struct ccw_device *cdev = to_ccwdev(dev);
 288
 289         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 290 }
 291
 292 int ccw_device_is_orphan(struct ccw_device *cdev)
 293 {
 294         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 295 }
 296
 297 static void ccw_device_unregister(struct ccw_device *cdev)
 298 {
 299         if (device_is_registered(&cdev->dev)) {
 300                 /* Undo device_add(). */
 301                 device_del(&cdev->dev);
 302         }
 303         if (cdev->private->flags.initialized) {
 304                 cdev->private->flags.initialized = 0;
 305                 /* Release reference from device_initialize(). */
 306                 put_device(&cdev->dev);
 307         }
 308 }
 309
 310 static void io_subchannel_quiesce(struct subchannel *);
 311
 312 /**
 313  * ccw_device_set_offline() - disable a ccw device for I/O
 314  * @cdev: target ccw device
 315  *
 316  * This function calls the driver's set_offline() function for @cdev, if
 317  * given, and then disables @cdev.
 318  * Returns:
 319  *   %0 on success and a negative error value on failure.
 320  * Context:
 321  *  enabled, ccw device lock not held
 322  */
 323 int ccw_device_set_offline(struct ccw_device *cdev)
 324 {
 325         struct subchannel *sch;
 326         int ret, state;
 327
 328         if (!cdev)
 329                 return -ENODEV;
 330         if (!cdev->online || !cdev->drv)
 331                 return -EINVAL;
 332
 333         if (cdev->drv->set_offline) {
 334                 ret = cdev->drv->set_offline(cdev);
 335                 if (ret != 0)
 336                         return ret;
 337         }
 338         spin_lock_irq(cdev->ccwlock);
 339         sch = to_subchannel(cdev->dev.parent);
 340         cdev->online = 0;
 341         /* Wait until a final state or DISCONNECTED is reached */
 342         while (!dev_fsm_final_state(cdev) &&
 343                cdev->private->state != DEV_STATE_DISCONNECTED) {
 344                 spin_unlock_irq(cdev->ccwlock);
 345                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 346                            cdev->private->state == DEV_STATE_DISCONNECTED));
 347                 spin_lock_irq(cdev->ccwlock);
 348         }
 349         do {
 350                 ret = ccw_device_offline(cdev);
 351                 if (!ret)
 352                         break;
 353                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 354                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 355                               cdev->private->dev_id.devno);
 356                 if (ret != -EBUSY)
 357                         goto error;
 358                 state = cdev->private->state;
 359                 spin_unlock_irq(cdev->ccwlock);
 360                 io_subchannel_quiesce(sch);
 361                 spin_lock_irq(cdev->ccwlock);
 362                 cdev->private->state = state;
 363         } while (ret == -EBUSY);
 364         spin_unlock_irq(cdev->ccwlock);
 365         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 366                    cdev->private->state == DEV_STATE_DISCONNECTED));
 367         /* Inform the user if set offline failed. */
 368         if (cdev->private->state == DEV_STATE_BOXED) {
 369                 pr_warn("%s: The device entered boxed state while being set offline\n",
 370                         dev_name(&cdev->dev));
 371         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 372                 pr_warn("%s: The device stopped operating while being set offline\n",
 373                         dev_name(&cdev->dev));
 374         }
 375         /* Give up reference from ccw_device_set_online(). */
 376         put_device(&cdev->dev);
 377         return 0;
 378
 379 error:
 380         cdev->private->state = DEV_STATE_OFFLINE;
 381         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 382         spin_unlock_irq(cdev->ccwlock);
 383         /* Give up reference from ccw_device_set_online(). */
 384         put_device(&cdev->dev);
 385         return -ENODEV;
 386 }
 387
 388 /**
 389  * ccw_device_set_online() - enable a ccw device for I/O
 390  * @cdev: target ccw device
 391  *
 392  * This function first enables @cdev and then calls the driver's set_online()
 393  * function for @cdev, if given. If set_online() returns an error, @cdev is
 394  * disabled again.
 395  * Returns:
 396  *   %0 on success and a negative error value on failure.
 397  * Context:
 398  *  enabled, ccw device lock not held
 399  */
 400 int ccw_device_set_online(struct ccw_device *cdev)
 401 {
 402         int ret;
 403         int ret2;
 404
 405         if (!cdev)
 406                 return -ENODEV;
 407         if (cdev->online || !cdev->drv)
 408                 return -EINVAL;
 409         /* Hold on to an extra reference while device is online. */
 410         if (!get_device(&cdev->dev))
 411                 return -ENODEV;
 412
 413         spin_lock_irq(cdev->ccwlock);
 414         ret = ccw_device_online(cdev);
 415         spin_unlock_irq(cdev->ccwlock);
 416         if (ret == 0)
 417                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 418         else {
 419                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 420                               "device 0.%x.%04x\n",
 421                               ret, cdev->private->dev_id.ssid,
 422                               cdev->private->dev_id.devno);
 423                 /* Give up online reference since onlining failed. */
 424                 put_device(&cdev->dev);
 425                 return ret;
 426         }
 427         spin_lock_irq(cdev->ccwlock);
 428         /* Check if online processing was successful */
 429         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 430             (cdev->private->state != DEV_STATE_W4SENSE)) {
 431                 spin_unlock_irq(cdev->ccwlock);
 432                 /* Inform the user that set online failed. */
 433                 if (cdev->private->state == DEV_STATE_BOXED) {
 434                         pr_warn("%s: Setting the device online failed because it is boxed\n",
 435                                 dev_name(&cdev->dev));
 436                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 437                         pr_warn("%s: Setting the device online failed 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_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n",
 623                         sch->schid.ssid, sch->schid.sch_no, rc);
 624                 return rc;
 625         }
 626         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 627                   sch->schid.ssid, sch->schid.sch_no);
 628         return count;
 629 }
 630
 631 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
 632                         char *buf)
 633 {
 634         struct subchannel *sch = to_subchannel(dev);
 635
 636         return sprintf(buf, "%02x\n", sch->vpm);
 637 }
 638
 639 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 640 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 641 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 642 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 643 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 644 static DEVICE_ATTR(online, 0644, online_show, online_store);
 645 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 646 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 647 static DEVICE_ATTR(vpm, 0444, vpm_show, NULL);
 648
 649 static struct attribute *io_subchannel_attrs[] = {
 650         &dev_attr_chpids.attr,
 651         &dev_attr_pimpampom.attr,
 652         &dev_attr_logging.attr,
 653         &dev_attr_vpm.attr,
 654         NULL,
 655 };
 656
 657 static struct attribute_group io_subchannel_attr_group = {
 658         .attrs = io_subchannel_attrs,
 659 };
 660
 661 static struct attribute * ccwdev_attrs[] = {
 662         &dev_attr_devtype.attr,
 663         &dev_attr_cutype.attr,
 664         &dev_attr_modalias.attr,
 665         &dev_attr_online.attr,
 666         &dev_attr_cmb_enable.attr,
 667         &dev_attr_availability.attr,
 668         NULL,
 669 };
 670
 671 static struct attribute_group ccwdev_attr_group = {
 672         .attrs = ccwdev_attrs,
 673 };
 674
 675 static const struct attribute_group *ccwdev_attr_groups[] = {
 676         &ccwdev_attr_group,
 677         NULL,
 678 };
 679
 680 static int ccw_device_add(struct ccw_device *cdev)
 681 {
 682         struct device *dev = &cdev->dev;
 683
 684         dev->bus = &ccw_bus_type;
 685         return device_add(dev);
 686 }
 687
 688 static int match_dev_id(struct device *dev, void *data)
 689 {
 690         struct ccw_device *cdev = to_ccwdev(dev);
 691         struct ccw_dev_id *dev_id = data;
 692
 693         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 694 }
 695
 696 /**
 697  * get_ccwdev_by_dev_id() - obtain device from a ccw device id
 698  * @dev_id: id of the device to be searched
 699  *
 700  * This function searches all devices attached to the ccw bus for a device
 701  * matching @dev_id.
 702  * Returns:
 703  *  If a device is found its reference count is increased and returned;
 704  *  else %NULL is returned.
 705  */
 706 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 707 {
 708         struct device *dev;
 709
 710         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 711
 712         return dev ? to_ccwdev(dev) : NULL;
 713 }
 714 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
 715
 716 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 717 {
 718         int ret;
 719
 720         if (device_is_registered(&cdev->dev)) {
 721                 device_release_driver(&cdev->dev);
 722                 ret = device_attach(&cdev->dev);
 723                 WARN_ON(ret == -ENODEV);
 724         }
 725 }
 726
 727 static void
 728 ccw_device_release(struct device *dev)
 729 {
 730         struct ccw_device *cdev;
 731
 732         cdev = to_ccwdev(dev);
 733         /* Release reference of parent subchannel. */
 734         put_device(cdev->dev.parent);
 735         kfree(cdev->private);
 736         kfree(cdev);
 737 }
 738
 739 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 740 {
 741         struct ccw_device *cdev;
 742
 743         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 744         if (cdev) {
 745                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 746                                         GFP_KERNEL | GFP_DMA);
 747                 if (cdev->private)
 748                         return cdev;
 749         }
 750         kfree(cdev);
 751         return ERR_PTR(-ENOMEM);
 752 }
 753
 754 static void ccw_device_todo(struct work_struct *work);
 755
 756 static int io_subchannel_initialize_dev(struct subchannel *sch,
 757                                         struct ccw_device *cdev)
 758 {
 759         struct ccw_device_private *priv = cdev->private;
 760         int ret;
 761
 762         priv->cdev = cdev;
 763         priv->int_class = IRQIO_CIO;
 764         priv->state = DEV_STATE_NOT_OPER;
 765         priv->dev_id.devno = sch->schib.pmcw.dev;
 766         priv->dev_id.ssid = sch->schid.ssid;
 767
 768         INIT_WORK(&priv->todo_work, ccw_device_todo);
 769         INIT_LIST_HEAD(&priv->cmb_list);
 770         init_waitqueue_head(&priv->wait_q);
 771         init_timer(&priv->timer);
 772
 773         atomic_set(&priv->onoff, 0);
 774         cdev->ccwlock = sch->lock;
 775         cdev->dev.parent = &sch->dev;
 776         cdev->dev.release = ccw_device_release;
 777         cdev->dev.groups = ccwdev_attr_groups;
 778         /* Do first half of device_register. */
 779         device_initialize(&cdev->dev);
 780         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 781                            cdev->private->dev_id.devno);
 782         if (ret)
 783                 goto out_put;
 784         if (!get_device(&sch->dev)) {
 785                 ret = -ENODEV;
 786                 goto out_put;
 787         }
 788         priv->flags.initialized = 1;
 789         spin_lock_irq(sch->lock);
 790         sch_set_cdev(sch, cdev);
 791         spin_unlock_irq(sch->lock);
 792         return 0;
 793
 794 out_put:
 795         /* Release reference from device_initialize(). */
 796         put_device(&cdev->dev);
 797         return ret;
 798 }
 799
 800 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 801 {
 802         struct ccw_device *cdev;
 803         int ret;
 804
 805         cdev = io_subchannel_allocate_dev(sch);
 806         if (!IS_ERR(cdev)) {
 807                 ret = io_subchannel_initialize_dev(sch, cdev);
 808                 if (ret)
 809                         cdev = ERR_PTR(ret);
 810         }
 811         return cdev;
 812 }
 813
 814 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 815
 816 static void sch_create_and_recog_new_device(struct subchannel *sch)
 817 {
 818         struct ccw_device *cdev;
 819
 820         /* Need to allocate a new ccw device. */
 821         cdev = io_subchannel_create_ccwdev(sch);
 822         if (IS_ERR(cdev)) {
 823                 /* OK, we did everything we could... */
 824                 css_sch_device_unregister(sch);
 825                 return;
 826         }
 827         /* Start recognition for the new ccw device. */
 828         io_subchannel_recog(cdev, sch);
 829 }
 830
 831 /*
 832  * Register recognized device.
 833  */
 834 static void io_subchannel_register(struct ccw_device *cdev)
 835 {
 836         struct subchannel *sch;
 837         int ret, adjust_init_count = 1;
 838         unsigned long flags;
 839
 840         sch = to_subchannel(cdev->dev.parent);
 841         /*
 842          * Check if subchannel is still registered. It may have become
 843          * unregistered if a machine check hit us after finishing
 844          * device recognition but before the register work could be
 845          * queued.
 846          */
 847         if (!device_is_registered(&sch->dev))
 848                 goto out_err;
 849         css_update_ssd_info(sch);
 850         /*
 851          * io_subchannel_register() will also be called after device
 852          * recognition has been done for a boxed device (which will already
 853          * be registered). We need to reprobe since we may now have sense id
 854          * information.
 855          */
 856         if (device_is_registered(&cdev->dev)) {
 857                 if (!cdev->drv) {
 858                         ret = device_reprobe(&cdev->dev);
 859                         if (ret)
 860                                 /* We can't do much here. */
 861                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 862                                               " %d for 0.%x.%04x\n", ret,
 863                                               cdev->private->dev_id.ssid,
 864                                               cdev->private->dev_id.devno);
 865                 }
 866                 adjust_init_count = 0;
 867                 goto out;
 868         }
 869         /*
 870          * Now we know this subchannel will stay, we can throw
 871          * our delayed uevent.
 872          */
 873         dev_set_uevent_suppress(&sch->dev, 0);
 874         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 875         /* make it known to the system */
 876         ret = ccw_device_add(cdev);
 877         if (ret) {
 878                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 879                               cdev->private->dev_id.ssid,
 880                               cdev->private->dev_id.devno, ret);
 881                 spin_lock_irqsave(sch->lock, flags);
 882                 sch_set_cdev(sch, NULL);
 883                 spin_unlock_irqrestore(sch->lock, flags);
 884                 /* Release initial device reference. */
 885                 put_device(&cdev->dev);
 886                 goto out_err;
 887         }
 888 out:
 889         cdev->private->flags.recog_done = 1;
 890         wake_up(&cdev->private->wait_q);
 891 out_err:
 892         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 893                 wake_up(&ccw_device_init_wq);
 894 }
 895
 896 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 897 {
 898         struct subchannel *sch;
 899
 900         /* Get subchannel reference for local processing. */
 901         if (!get_device(cdev->dev.parent))
 902                 return;
 903         sch = to_subchannel(cdev->dev.parent);
 904         css_sch_device_unregister(sch);
 905         /* Release subchannel reference for local processing. */
 906         put_device(&sch->dev);
 907 }
 908
 909 /*
 910  * subchannel recognition done. Called from the state machine.
 911  */
 912 void
 913 io_subchannel_recog_done(struct ccw_device *cdev)
 914 {
 915         if (css_init_done == 0) {
 916                 cdev->private->flags.recog_done = 1;
 917                 return;
 918         }
 919         switch (cdev->private->state) {
 920         case DEV_STATE_BOXED:
 921                 /* Device did not respond in time. */
 922         case DEV_STATE_NOT_OPER:
 923                 cdev->private->flags.recog_done = 1;
 924                 /* Remove device found not operational. */
 925                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 926                 if (atomic_dec_and_test(&ccw_device_init_count))
 927                         wake_up(&ccw_device_init_wq);
 928                 break;
 929         case DEV_STATE_OFFLINE:
 930                 /*
 931                  * We can't register the device in interrupt context so
 932                  * we schedule a work item.
 933                  */
 934                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 935                 break;
 936         }
 937 }
 938
 939 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 940 {
 941         /* Increase counter of devices currently in recognition. */
 942         atomic_inc(&ccw_device_init_count);
 943
 944         /* Start async. device sensing. */
 945         spin_lock_irq(sch->lock);
 946         ccw_device_recognition(cdev);
 947         spin_unlock_irq(sch->lock);
 948 }
 949
 950 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 951                                   struct subchannel *sch)
 952 {
 953         struct subchannel *old_sch;
 954         int rc, old_enabled = 0;
 955
 956         old_sch = to_subchannel(cdev->dev.parent);
 957         /* Obtain child reference for new parent. */
 958         if (!get_device(&sch->dev))
 959                 return -ENODEV;
 960
 961         if (!sch_is_pseudo_sch(old_sch)) {
 962                 spin_lock_irq(old_sch->lock);
 963                 old_enabled = old_sch->schib.pmcw.ena;
 964                 rc = 0;
 965                 if (old_enabled)
 966                         rc = cio_disable_subchannel(old_sch);
 967                 spin_unlock_irq(old_sch->lock);
 968                 if (rc == -EBUSY) {
 969                         /* Release child reference for new parent. */
 970                         put_device(&sch->dev);
 971                         return rc;
 972                 }
 973         }
 974
 975         mutex_lock(&sch->reg_mutex);
 976         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 977         mutex_unlock(&sch->reg_mutex);
 978         if (rc) {
 979                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 980                               cdev->private->dev_id.ssid,
 981                               cdev->private->dev_id.devno, sch->schid.ssid,
 982                               sch->schib.pmcw.dev, rc);
 983                 if (old_enabled) {
 984                         /* Try to reenable the old subchannel. */
 985                         spin_lock_irq(old_sch->lock);
 986                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 987                         spin_unlock_irq(old_sch->lock);
 988                 }
 989                 /* Release child reference for new parent. */
 990                 put_device(&sch->dev);
 991                 return rc;
 992         }
 993         /* Clean up old subchannel. */
 994         if (!sch_is_pseudo_sch(old_sch)) {
 995                 spin_lock_irq(old_sch->lock);
 996                 sch_set_cdev(old_sch, NULL);
 997                 spin_unlock_irq(old_sch->lock);
 998                 css_schedule_eval(old_sch->schid);
 999         }
1000         /* Release child reference for old parent. */
1001         put_device(&old_sch->dev);
1002         /* Initialize new subchannel. */
1003         spin_lock_irq(sch->lock);
1004         cdev->ccwlock = sch->lock;
1005         if (!sch_is_pseudo_sch(sch))
1006                 sch_set_cdev(sch, cdev);
1007         spin_unlock_irq(sch->lock);
1008         if (!sch_is_pseudo_sch(sch))
1009                 css_update_ssd_info(sch);
1010         return 0;
1011 }
1012
1013 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1014 {
1015         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1016         struct channel_subsystem *css = to_css(sch->dev.parent);
1017
1018         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1019 }
1020
1021 static void io_subchannel_irq(struct subchannel *sch)
1022 {
1023         struct ccw_device *cdev;
1024
1025         cdev = sch_get_cdev(sch);
1026
1027         CIO_TRACE_EVENT(6, "IRQ");
1028         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1029         if (cdev)
1030                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1031         else
1032                 inc_irq_stat(IRQIO_CIO);
1033 }
1034
1035 void io_subchannel_init_config(struct subchannel *sch)
1036 {
1037         memset(&sch->config, 0, sizeof(sch->config));
1038         sch->config.csense = 1;
1039 }
1040
1041 static void io_subchannel_init_fields(struct subchannel *sch)
1042 {
1043         if (cio_is_console(sch->schid))
1044                 sch->opm = 0xff;
1045         else
1046                 sch->opm = chp_get_sch_opm(sch);
1047         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1048         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1049
1050         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1051                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1052                       sch->schib.pmcw.dev, sch->schid.ssid,
1053                       sch->schid.sch_no, sch->schib.pmcw.pim,
1054                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1055
1056         io_subchannel_init_config(sch);
1057 }
1058
1059 /*
1060  * Note: We always return 0 so that we bind to the device even on error.
1061  * This is needed so that our remove function is called on unregister.
1062  */
1063 static int io_subchannel_probe(struct subchannel *sch)
1064 {
1065         struct io_subchannel_private *io_priv;
1066         struct ccw_device *cdev;
1067         int rc;
1068
1069         if (cio_is_console(sch->schid)) {
1070                 rc = sysfs_create_group(&sch->dev.kobj,
1071                                         &io_subchannel_attr_group);
1072                 if (rc)
1073                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1074                                       "attributes for subchannel "
1075                                       "0.%x.%04x (rc=%d)\n",
1076                                       sch->schid.ssid, sch->schid.sch_no, rc);
1077                 /*
1078                  * The console subchannel already has an associated ccw_device.
1079                  * Throw the delayed uevent for the subchannel, register
1080                  * the ccw_device and exit.
1081                  */
1082                 dev_set_uevent_suppress(&sch->dev, 0);
1083                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1084                 cdev = sch_get_cdev(sch);
1085                 rc = ccw_device_add(cdev);
1086                 if (rc) {
1087                         /* Release online reference. */
1088                         put_device(&cdev->dev);
1089                         goto out_schedule;
1090                 }
1091                 if (atomic_dec_and_test(&ccw_device_init_count))
1092                         wake_up(&ccw_device_init_wq);
1093                 return 0;
1094         }
1095         io_subchannel_init_fields(sch);
1096         rc = cio_commit_config(sch);
1097         if (rc)
1098                 goto out_schedule;
1099         rc = sysfs_create_group(&sch->dev.kobj,
1100                                 &io_subchannel_attr_group);
1101         if (rc)
1102                 goto out_schedule;
1103         /* Allocate I/O subchannel private data. */
1104         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1105         if (!io_priv)
1106                 goto out_schedule;
1107
1108         set_io_private(sch, io_priv);
1109         css_schedule_eval(sch->schid);
1110         return 0;
1111
1112 out_schedule:
1113         spin_lock_irq(sch->lock);
1114         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1115         spin_unlock_irq(sch->lock);
1116         return 0;
1117 }
1118
1119 static int
1120 io_subchannel_remove (struct subchannel *sch)
1121 {
1122         struct io_subchannel_private *io_priv = to_io_private(sch);
1123         struct ccw_device *cdev;
1124
1125         cdev = sch_get_cdev(sch);
1126         if (!cdev)
1127                 goto out_free;
1128         io_subchannel_quiesce(sch);
1129         /* Set ccw device to not operational and drop reference. */
1130         spin_lock_irq(cdev->ccwlock);
1131         sch_set_cdev(sch, NULL);
1132         set_io_private(sch, NULL);
1133         cdev->private->state = DEV_STATE_NOT_OPER;
1134         spin_unlock_irq(cdev->ccwlock);
1135         ccw_device_unregister(cdev);
1136 out_free:
1137         kfree(io_priv);
1138         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1139         return 0;
1140 }
1141
1142 static void io_subchannel_verify(struct subchannel *sch)
1143 {
1144         struct ccw_device *cdev;
1145
1146         cdev = sch_get_cdev(sch);
1147         if (cdev)
1148                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1149 }
1150
1151 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1152 {
1153         struct ccw_device *cdev;
1154
1155         cdev = sch_get_cdev(sch);
1156         if (!cdev)
1157                 return;
1158         if (cio_update_schib(sch))
1159                 goto err;
1160         /* Check for I/O on path. */
1161         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1162                 goto out;
1163         if (cdev->private->state == DEV_STATE_ONLINE) {
1164                 ccw_device_kill_io(cdev);
1165                 goto out;
1166         }
1167         if (cio_clear(sch))
1168                 goto err;
1169 out:
1170         /* Trigger path verification. */
1171         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1172         return;
1173
1174 err:
1175         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1176 }
1177
1178 static int io_subchannel_chp_event(struct subchannel *sch,
1179                                    struct chp_link *link, int event)
1180 {
1181         struct ccw_device *cdev = sch_get_cdev(sch);
1182         int mask;
1183
1184         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1185         if (!mask)
1186                 return 0;
1187         switch (event) {
1188         case CHP_VARY_OFF:
1189                 sch->opm &= ~mask;
1190                 sch->lpm &= ~mask;
1191                 if (cdev)
1192                         cdev->private->path_gone_mask |= mask;
1193                 io_subchannel_terminate_path(sch, mask);
1194                 break;
1195         case CHP_VARY_ON:
1196                 sch->opm |= mask;
1197                 sch->lpm |= mask;
1198                 if (cdev)
1199                         cdev->private->path_new_mask |= mask;
1200                 io_subchannel_verify(sch);
1201                 break;
1202         case CHP_OFFLINE:
1203                 if (cio_update_schib(sch))
1204                         return -ENODEV;
1205                 if (cdev)
1206                         cdev->private->path_gone_mask |= mask;
1207                 io_subchannel_terminate_path(sch, mask);
1208                 break;
1209         case CHP_ONLINE:
1210                 if (cio_update_schib(sch))
1211                         return -ENODEV;
1212                 sch->lpm |= mask & sch->opm;
1213                 if (cdev)
1214                         cdev->private->path_new_mask |= mask;
1215                 io_subchannel_verify(sch);
1216                 break;
1217         }
1218         return 0;
1219 }
1220
1221 static void io_subchannel_quiesce(struct subchannel *sch)
1222 {
1223         struct ccw_device *cdev;
1224         int ret;
1225
1226         spin_lock_irq(sch->lock);
1227         cdev = sch_get_cdev(sch);
1228         if (cio_is_console(sch->schid))
1229                 goto out_unlock;
1230         if (!sch->schib.pmcw.ena)
1231                 goto out_unlock;
1232         ret = cio_disable_subchannel(sch);
1233         if (ret != -EBUSY)
1234                 goto out_unlock;
1235         if (cdev->handler)
1236                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1237         while (ret == -EBUSY) {
1238                 cdev->private->state = DEV_STATE_QUIESCE;
1239                 cdev->private->iretry = 255;
1240                 ret = ccw_device_cancel_halt_clear(cdev);
1241                 if (ret == -EBUSY) {
1242                         ccw_device_set_timeout(cdev, HZ/10);
1243                         spin_unlock_irq(sch->lock);
1244                         wait_event(cdev->private->wait_q,
1245                                    cdev->private->state != DEV_STATE_QUIESCE);
1246                         spin_lock_irq(sch->lock);
1247                 }
1248                 ret = cio_disable_subchannel(sch);
1249         }
1250 out_unlock:
1251         spin_unlock_irq(sch->lock);
1252 }
1253
1254 static void io_subchannel_shutdown(struct subchannel *sch)
1255 {
1256         io_subchannel_quiesce(sch);
1257 }
1258
1259 static int device_is_disconnected(struct ccw_device *cdev)
1260 {
1261         if (!cdev)
1262                 return 0;
1263         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1264                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1265 }
1266
1267 static int recovery_check(struct device *dev, void *data)
1268 {
1269         struct ccw_device *cdev = to_ccwdev(dev);
1270         int *redo = data;
1271
1272         spin_lock_irq(cdev->ccwlock);
1273         switch (cdev->private->state) {
1274         case DEV_STATE_DISCONNECTED:
1275                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1276                               cdev->private->dev_id.ssid,
1277                               cdev->private->dev_id.devno);
1278                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1279                 *redo = 1;
1280                 break;
1281         case DEV_STATE_DISCONNECTED_SENSE_ID:
1282                 *redo = 1;
1283                 break;
1284         }
1285         spin_unlock_irq(cdev->ccwlock);
1286
1287         return 0;
1288 }
1289
1290 static void recovery_work_func(struct work_struct *unused)
1291 {
1292         int redo = 0;
1293
1294         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1295         if (redo) {
1296                 spin_lock_irq(&recovery_lock);
1297                 if (!timer_pending(&recovery_timer)) {
1298                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1299                                 recovery_phase++;
1300                         mod_timer(&recovery_timer, jiffies +
1301                                   recovery_delay[recovery_phase] * HZ);
1302                 }
1303                 spin_unlock_irq(&recovery_lock);
1304         } else
1305                 CIO_MSG_EVENT(4, "recovery: end\n");
1306 }
1307
1308 static DECLARE_WORK(recovery_work, recovery_work_func);
1309
1310 static void recovery_func(unsigned long data)
1311 {
1312         /*
1313          * We can't do our recovery in softirq context and it's not
1314          * performance critical, so we schedule it.
1315          */
1316         schedule_work(&recovery_work);
1317 }
1318
1319 static void ccw_device_schedule_recovery(void)
1320 {
1321         unsigned long flags;
1322
1323         CIO_MSG_EVENT(4, "recovery: schedule\n");
1324         spin_lock_irqsave(&recovery_lock, flags);
1325         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1326                 recovery_phase = 0;
1327                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1328         }
1329         spin_unlock_irqrestore(&recovery_lock, flags);
1330 }
1331
1332 static int purge_fn(struct device *dev, void *data)
1333 {
1334         struct ccw_device *cdev = to_ccwdev(dev);
1335         struct ccw_dev_id *id = &cdev->private->dev_id;
1336
1337         spin_lock_irq(cdev->ccwlock);
1338         if (is_blacklisted(id->ssid, id->devno) &&
1339             (cdev->private->state == DEV_STATE_OFFLINE) &&
1340             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1341                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1342                               id->devno);
1343                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1344                 atomic_set(&cdev->private->onoff, 0);
1345         }
1346         spin_unlock_irq(cdev->ccwlock);
1347         /* Abort loop in case of pending signal. */
1348         if (signal_pending(current))
1349                 return -EINTR;
1350
1351         return 0;
1352 }
1353
1354 /**
1355  * ccw_purge_blacklisted - purge unused, blacklisted devices
1356  *
1357  * Unregister all ccw devices that are offline and on the blacklist.
1358  */
1359 int ccw_purge_blacklisted(void)
1360 {
1361         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1362         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1363         return 0;
1364 }
1365
1366 void ccw_device_set_disconnected(struct ccw_device *cdev)
1367 {
1368         if (!cdev)
1369                 return;
1370         ccw_device_set_timeout(cdev, 0);
1371         cdev->private->flags.fake_irb = 0;
1372         cdev->private->state = DEV_STATE_DISCONNECTED;
1373         if (cdev->online)
1374                 ccw_device_schedule_recovery();
1375 }
1376
1377 void ccw_device_set_notoper(struct ccw_device *cdev)
1378 {
1379         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1380
1381         CIO_TRACE_EVENT(2, "notoper");
1382         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1383         ccw_device_set_timeout(cdev, 0);
1384         cio_disable_subchannel(sch);
1385         cdev->private->state = DEV_STATE_NOT_OPER;
1386 }
1387
1388 enum io_sch_action {
1389         IO_SCH_UNREG,
1390         IO_SCH_ORPH_UNREG,
1391         IO_SCH_ATTACH,
1392         IO_SCH_UNREG_ATTACH,
1393         IO_SCH_ORPH_ATTACH,
1394         IO_SCH_REPROBE,
1395         IO_SCH_VERIFY,
1396         IO_SCH_DISC,
1397         IO_SCH_NOP,
1398 };
1399
1400 static enum io_sch_action sch_get_action(struct subchannel *sch)
1401 {
1402         struct ccw_device *cdev;
1403
1404         cdev = sch_get_cdev(sch);
1405         if (cio_update_schib(sch)) {
1406                 /* Not operational. */
1407                 if (!cdev)
1408                         return IO_SCH_UNREG;
1409                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1410                         return IO_SCH_UNREG;
1411                 return IO_SCH_ORPH_UNREG;
1412         }
1413         /* Operational. */
1414         if (!cdev)
1415                 return IO_SCH_ATTACH;
1416         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1417                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1418                         return IO_SCH_UNREG_ATTACH;
1419                 return IO_SCH_ORPH_ATTACH;
1420         }
1421         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1422                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1423                         return IO_SCH_UNREG;
1424                 return IO_SCH_DISC;
1425         }
1426         if (device_is_disconnected(cdev))
1427                 return IO_SCH_REPROBE;
1428         if (cdev->online && !cdev->private->flags.resuming)
1429                 return IO_SCH_VERIFY;
1430         if (cdev->private->state == DEV_STATE_NOT_OPER)
1431                 return IO_SCH_UNREG_ATTACH;
1432         return IO_SCH_NOP;
1433 }
1434
1435 /**
1436  * io_subchannel_sch_event - process subchannel event
1437  * @sch: subchannel
1438  * @process: non-zero if function is called in process context
1439  *
1440  * An unspecified event occurred for this subchannel. Adjust data according
1441  * to the current operational state of the subchannel and device. Return
1442  * zero when the event has been handled sufficiently or -EAGAIN when this
1443  * function should be called again in process context.
1444  */
1445 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1446 {
1447         unsigned long flags;
1448         struct ccw_device *cdev;
1449         struct ccw_dev_id dev_id;
1450         enum io_sch_action action;
1451         int rc = -EAGAIN;
1452
1453         spin_lock_irqsave(sch->lock, flags);
1454         if (!device_is_registered(&sch->dev))
1455                 goto out_unlock;
1456         if (work_pending(&sch->todo_work))
1457                 goto out_unlock;
1458         cdev = sch_get_cdev(sch);
1459         if (cdev && work_pending(&cdev->private->todo_work))
1460                 goto out_unlock;
1461         action = sch_get_action(sch);
1462         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1463                       sch->schid.ssid, sch->schid.sch_no, process,
1464                       action);
1465         /* Perform immediate actions while holding the lock. */
1466         switch (action) {
1467         case IO_SCH_REPROBE:
1468                 /* Trigger device recognition. */
1469                 ccw_device_trigger_reprobe(cdev);
1470                 rc = 0;
1471                 goto out_unlock;
1472         case IO_SCH_VERIFY:
1473                 /* Trigger path verification. */
1474                 io_subchannel_verify(sch);
1475                 rc = 0;
1476                 goto out_unlock;
1477         case IO_SCH_DISC:
1478                 ccw_device_set_disconnected(cdev);
1479                 rc = 0;
1480                 goto out_unlock;
1481         case IO_SCH_ORPH_UNREG:
1482         case IO_SCH_ORPH_ATTACH:
1483                 ccw_device_set_disconnected(cdev);
1484                 break;
1485         case IO_SCH_UNREG_ATTACH:
1486         case IO_SCH_UNREG:
1487                 if (!cdev)
1488                         break;
1489                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1490                         /*
1491                          * Note: delayed work triggered by this event
1492                          * and repeated calls to sch_event are synchronized
1493                          * by the above check for work_pending(cdev).
1494                          */
1495                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1496                 } else
1497                         ccw_device_set_notoper(cdev);
1498                 break;
1499         case IO_SCH_NOP:
1500                 rc = 0;
1501                 goto out_unlock;
1502         default:
1503                 break;
1504         }
1505         spin_unlock_irqrestore(sch->lock, flags);
1506         /* All other actions require process context. */
1507         if (!process)
1508                 goto out;
1509         /* Handle attached ccw device. */
1510         switch (action) {
1511         case IO_SCH_ORPH_UNREG:
1512         case IO_SCH_ORPH_ATTACH:
1513                 /* Move ccw device to orphanage. */
1514                 rc = ccw_device_move_to_orph(cdev);
1515                 if (rc)
1516                         goto out;
1517                 break;
1518         case IO_SCH_UNREG_ATTACH:
1519                 spin_lock_irqsave(sch->lock, flags);
1520                 if (cdev->private->flags.resuming) {
1521                         /* Device will be handled later. */
1522                         rc = 0;
1523                         goto out_unlock;
1524                 }
1525                 sch_set_cdev(sch, NULL);
1526                 spin_unlock_irqrestore(sch->lock, flags);
1527                 /* Unregister ccw device. */
1528                 ccw_device_unregister(cdev);
1529                 break;
1530         default:
1531                 break;
1532         }
1533         /* Handle subchannel. */
1534         switch (action) {
1535         case IO_SCH_ORPH_UNREG:
1536         case IO_SCH_UNREG:
1537                 if (!cdev || !cdev->private->flags.resuming)
1538                         css_sch_device_unregister(sch);
1539                 break;
1540         case IO_SCH_ORPH_ATTACH:
1541         case IO_SCH_UNREG_ATTACH:
1542         case IO_SCH_ATTACH:
1543                 dev_id.ssid = sch->schid.ssid;
1544                 dev_id.devno = sch->schib.pmcw.dev;
1545                 cdev = get_ccwdev_by_dev_id(&dev_id);
1546                 if (!cdev) {
1547                         sch_create_and_recog_new_device(sch);
1548                         break;
1549                 }
1550                 rc = ccw_device_move_to_sch(cdev, sch);
1551                 if (rc) {
1552                         /* Release reference from get_ccwdev_by_dev_id() */
1553                         put_device(&cdev->dev);
1554                         goto out;
1555                 }
1556                 spin_lock_irqsave(sch->lock, flags);
1557                 ccw_device_trigger_reprobe(cdev);
1558                 spin_unlock_irqrestore(sch->lock, flags);
1559                 /* Release reference from get_ccwdev_by_dev_id() */
1560                 put_device(&cdev->dev);
1561                 break;
1562         default:
1563                 break;
1564         }
1565         return 0;
1566
1567 out_unlock:
1568         spin_unlock_irqrestore(sch->lock, flags);
1569 out:
1570         return rc;
1571 }
1572
1573 static void ccw_device_set_int_class(struct ccw_device *cdev)
1574 {
1575         struct ccw_driver *cdrv = cdev->drv;
1576
1577         /* Note: we interpret class 0 in this context as an uninitialized
1578          * field since it translates to a non-I/O interrupt class. */
1579         if (cdrv->int_class != 0)
1580                 cdev->private->int_class = cdrv->int_class;
1581         else
1582                 cdev->private->int_class = IRQIO_CIO;
1583 }
1584
1585 #ifdef CONFIG_CCW_CONSOLE
1586 int __init ccw_device_enable_console(struct ccw_device *cdev)
1587 {
1588         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1589         int rc;
1590
1591         if (!cdev->drv || !cdev->handler)
1592                 return -EINVAL;
1593
1594         io_subchannel_init_fields(sch);
1595         rc = cio_commit_config(sch);
1596         if (rc)
1597                 return rc;
1598         sch->driver = &io_subchannel_driver;
1599         io_subchannel_recog(cdev, sch);
1600         /* Now wait for the async. recognition to come to an end. */
1601         spin_lock_irq(cdev->ccwlock);
1602         while (!dev_fsm_final_state(cdev))
1603                 ccw_device_wait_idle(cdev);
1604
1605         /* Hold on to an extra reference while device is online. */
1606         get_device(&cdev->dev);
1607         rc = ccw_device_online(cdev);
1608         if (rc)
1609                 goto out_unlock;
1610
1611         while (!dev_fsm_final_state(cdev))
1612                 ccw_device_wait_idle(cdev);
1613
1614         if (cdev->private->state == DEV_STATE_ONLINE)
1615                 cdev->online = 1;
1616         else
1617                 rc = -EIO;
1618 out_unlock:
1619         spin_unlock_irq(cdev->ccwlock);
1620         if (rc) /* Give up online reference since onlining failed. */
1621                 put_device(&cdev->dev);
1622         return rc;
1623 }
1624
1625 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1626 {
1627         struct io_subchannel_private *io_priv;
1628         struct ccw_device *cdev;
1629         struct subchannel *sch;
1630
1631         sch = cio_probe_console();
1632         if (IS_ERR(sch))
1633                 return ERR_CAST(sch);
1634
1635         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1636         if (!io_priv) {
1637                 put_device(&sch->dev);
1638                 return ERR_PTR(-ENOMEM);
1639         }
1640         set_io_private(sch, io_priv);
1641         cdev = io_subchannel_create_ccwdev(sch);
1642         if (IS_ERR(cdev)) {
1643                 put_device(&sch->dev);
1644                 kfree(io_priv);
1645                 return cdev;
1646         }
1647         cdev->drv = drv;
1648         ccw_device_set_int_class(cdev);
1649         return cdev;
1650 }
1651
1652 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1653 {
1654         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1655         struct io_subchannel_private *io_priv = to_io_private(sch);
1656
1657         set_io_private(sch, NULL);
1658         put_device(&sch->dev);
1659         put_device(&cdev->dev);
1660         kfree(io_priv);
1661 }
1662
1663 /**
1664  * ccw_device_wait_idle() - busy wait for device to become idle
1665  * @cdev: ccw device
1666  *
1667  * Poll until activity control is zero, that is, no function or data
1668  * transfer is pending/active.
1669  * Called with device lock being held.
1670  */
1671 void ccw_device_wait_idle(struct ccw_device *cdev)
1672 {
1673         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1674
1675         while (1) {
1676                 cio_tsch(sch);
1677                 if (sch->schib.scsw.cmd.actl == 0)
1678                         break;
1679                 udelay_simple(100);
1680         }
1681 }
1682
1683 static int ccw_device_pm_restore(struct device *dev);
1684
1685 int ccw_device_force_console(struct ccw_device *cdev)
1686 {
1687         return ccw_device_pm_restore(&cdev->dev);
1688 }
1689 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1690 #endif
1691
1692 /*
1693  * get ccw_device matching the busid, but only if owned by cdrv
1694  */
1695 static int
1696 __ccwdev_check_busid(struct device *dev, void *id)
1697 {
1698         char *bus_id;
1699
1700         bus_id = id;
1701
1702         return (strcmp(bus_id, dev_name(dev)) == 0);
1703 }
1704
1705
1706 /**
1707  * get_ccwdev_by_busid() - obtain device from a bus id
1708  * @cdrv: driver the device is owned by
1709  * @bus_id: bus id of the device to be searched
1710  *
1711  * This function searches all devices owned by @cdrv for a device with a bus
1712  * id matching @bus_id.
1713  * Returns:
1714  *  If a match is found, its reference count of the found device is increased
1715  *  and it is returned; else %NULL is returned.
1716  */
1717 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1718                                        const char *bus_id)
1719 {
1720         struct device *dev;
1721
1722         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1723                                  __ccwdev_check_busid);
1724
1725         return dev ? to_ccwdev(dev) : NULL;
1726 }
1727
1728 /************************** device driver handling ************************/
1729
1730 /* This is the implementation of the ccw_driver class. The probe, remove
1731  * and release methods are initially very similar to the device_driver
1732  * implementations, with the difference that they have ccw_device
1733  * arguments.
1734  *
1735  * A ccw driver also contains the information that is needed for
1736  * device matching.
1737  */
1738 static int
1739 ccw_device_probe (struct device *dev)
1740 {
1741         struct ccw_device *cdev = to_ccwdev(dev);
1742         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1743         int ret;
1744
1745         cdev->drv = cdrv; /* to let the driver call _set_online */
1746         ccw_device_set_int_class(cdev);
1747         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1748         if (ret) {
1749                 cdev->drv = NULL;
1750                 cdev->private->int_class = IRQIO_CIO;
1751                 return ret;
1752         }
1753
1754         return 0;
1755 }
1756
1757 static int ccw_device_remove(struct device *dev)
1758 {
1759         struct ccw_device *cdev = to_ccwdev(dev);
1760         struct ccw_driver *cdrv = cdev->drv;
1761         int ret;
1762
1763         if (cdrv->remove)
1764                 cdrv->remove(cdev);
1765
1766         spin_lock_irq(cdev->ccwlock);
1767         if (cdev->online) {
1768                 cdev->online = 0;
1769                 ret = ccw_device_offline(cdev);
1770                 spin_unlock_irq(cdev->ccwlock);
1771                 if (ret == 0)
1772                         wait_event(cdev->private->wait_q,
1773                                    dev_fsm_final_state(cdev));
1774                 else
1775                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1776                                       "device 0.%x.%04x\n",
1777                                       ret, cdev->private->dev_id.ssid,
1778                                       cdev->private->dev_id.devno);
1779                 /* Give up reference obtained in ccw_device_set_online(). */
1780                 put_device(&cdev->dev);
1781                 spin_lock_irq(cdev->ccwlock);
1782         }
1783         ccw_device_set_timeout(cdev, 0);
1784         cdev->drv = NULL;
1785         cdev->private->int_class = IRQIO_CIO;
1786         spin_unlock_irq(cdev->ccwlock);
1787         __disable_cmf(cdev);
1788
1789         return 0;
1790 }
1791
1792 static void ccw_device_shutdown(struct device *dev)
1793 {
1794         struct ccw_device *cdev;
1795
1796         cdev = to_ccwdev(dev);
1797         if (cdev->drv && cdev->drv->shutdown)
1798                 cdev->drv->shutdown(cdev);
1799         __disable_cmf(cdev);
1800 }
1801
1802 static int ccw_device_pm_prepare(struct device *dev)
1803 {
1804         struct ccw_device *cdev = to_ccwdev(dev);
1805
1806         if (work_pending(&cdev->private->todo_work))
1807                 return -EAGAIN;
1808         /* Fail while device is being set online/offline. */
1809         if (atomic_read(&cdev->private->onoff))
1810                 return -EAGAIN;
1811
1812         if (cdev->online && cdev->drv && cdev->drv->prepare)
1813                 return cdev->drv->prepare(cdev);
1814
1815         return 0;
1816 }
1817
1818 static void ccw_device_pm_complete(struct device *dev)
1819 {
1820         struct ccw_device *cdev = to_ccwdev(dev);
1821
1822         if (cdev->online && cdev->drv && cdev->drv->complete)
1823                 cdev->drv->complete(cdev);
1824 }
1825
1826 static int ccw_device_pm_freeze(struct device *dev)
1827 {
1828         struct ccw_device *cdev = to_ccwdev(dev);
1829         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1830         int ret, cm_enabled;
1831
1832         /* Fail suspend while device is in transistional state. */
1833         if (!dev_fsm_final_state(cdev))
1834                 return -EAGAIN;
1835         if (!cdev->online)
1836                 return 0;
1837         if (cdev->drv && cdev->drv->freeze) {
1838                 ret = cdev->drv->freeze(cdev);
1839                 if (ret)
1840                         return ret;
1841         }
1842
1843         spin_lock_irq(sch->lock);
1844         cm_enabled = cdev->private->cmb != NULL;
1845         spin_unlock_irq(sch->lock);
1846         if (cm_enabled) {
1847                 /* Don't have the css write on memory. */
1848                 ret = ccw_set_cmf(cdev, 0);
1849                 if (ret)
1850                         return ret;
1851         }
1852         /* From here on, disallow device driver I/O. */
1853         spin_lock_irq(sch->lock);
1854         ret = cio_disable_subchannel(sch);
1855         spin_unlock_irq(sch->lock);
1856
1857         return ret;
1858 }
1859
1860 static int ccw_device_pm_thaw(struct device *dev)
1861 {
1862         struct ccw_device *cdev = to_ccwdev(dev);
1863         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1864         int ret, cm_enabled;
1865
1866         if (!cdev->online)
1867                 return 0;
1868
1869         spin_lock_irq(sch->lock);
1870         /* Allow device driver I/O again. */
1871         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1872         cm_enabled = cdev->private->cmb != NULL;
1873         spin_unlock_irq(sch->lock);
1874         if (ret)
1875                 return ret;
1876
1877         if (cm_enabled) {
1878                 ret = ccw_set_cmf(cdev, 1);
1879                 if (ret)
1880                         return ret;
1881         }
1882
1883         if (cdev->drv && cdev->drv->thaw)
1884                 ret = cdev->drv->thaw(cdev);
1885
1886         return ret;
1887 }
1888
1889 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1890 {
1891         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1892
1893         spin_lock_irq(sch->lock);
1894         if (cio_is_console(sch->schid)) {
1895                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1896                 goto out_unlock;
1897         }
1898         /*
1899          * While we were sleeping, devices may have gone or become
1900          * available again. Kick re-detection.
1901          */
1902         cdev->private->flags.resuming = 1;
1903         cdev->private->path_new_mask = LPM_ANYPATH;
1904         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1905         spin_unlock_irq(sch->lock);
1906         css_wait_for_slow_path();
1907
1908         /* cdev may have been moved to a different subchannel. */
1909         sch = to_subchannel(cdev->dev.parent);
1910         spin_lock_irq(sch->lock);
1911         if (cdev->private->state != DEV_STATE_ONLINE &&
1912             cdev->private->state != DEV_STATE_OFFLINE)
1913                 goto out_unlock;
1914
1915         ccw_device_recognition(cdev);
1916         spin_unlock_irq(sch->lock);
1917         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1918                    cdev->private->state == DEV_STATE_DISCONNECTED);
1919         spin_lock_irq(sch->lock);
1920
1921 out_unlock:
1922         cdev->private->flags.resuming = 0;
1923         spin_unlock_irq(sch->lock);
1924 }
1925
1926 static int resume_handle_boxed(struct ccw_device *cdev)
1927 {
1928         cdev->private->state = DEV_STATE_BOXED;
1929         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1930                 return 0;
1931         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1932         return -ENODEV;
1933 }
1934
1935 static int resume_handle_disc(struct ccw_device *cdev)
1936 {
1937         cdev->private->state = DEV_STATE_DISCONNECTED;
1938         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1939                 return 0;
1940         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1941         return -ENODEV;
1942 }
1943
1944 static int ccw_device_pm_restore(struct device *dev)
1945 {
1946         struct ccw_device *cdev = to_ccwdev(dev);
1947         struct subchannel *sch;
1948         int ret = 0;
1949
1950         __ccw_device_pm_restore(cdev);
1951         sch = to_subchannel(cdev->dev.parent);
1952         spin_lock_irq(sch->lock);
1953         if (cio_is_console(sch->schid))
1954                 goto out_restore;
1955
1956         /* check recognition results */
1957         switch (cdev->private->state) {
1958         case DEV_STATE_OFFLINE:
1959         case DEV_STATE_ONLINE:
1960                 cdev->private->flags.donotify = 0;
1961                 break;
1962         case DEV_STATE_BOXED:
1963                 ret = resume_handle_boxed(cdev);
1964                 if (ret)
1965                         goto out_unlock;
1966                 goto out_restore;
1967         default:
1968                 ret = resume_handle_disc(cdev);
1969                 if (ret)
1970                         goto out_unlock;
1971                 goto out_restore;
1972         }
1973         /* check if the device type has changed */
1974         if (!ccw_device_test_sense_data(cdev)) {
1975                 ccw_device_update_sense_data(cdev);
1976                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1977                 ret = -ENODEV;
1978                 goto out_unlock;
1979         }
1980         if (!cdev->online)
1981                 goto out_unlock;
1982
1983         if (ccw_device_online(cdev)) {
1984                 ret = resume_handle_disc(cdev);
1985                 if (ret)
1986                         goto out_unlock;
1987                 goto out_restore;
1988         }
1989         spin_unlock_irq(sch->lock);
1990         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1991         spin_lock_irq(sch->lock);
1992
1993         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1994                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1995                 ret = -ENODEV;
1996                 goto out_unlock;
1997         }
1998
1999         /* reenable cmf, if needed */
2000         if (cdev->private->cmb) {
2001                 spin_unlock_irq(sch->lock);
2002                 ret = ccw_set_cmf(cdev, 1);
2003                 spin_lock_irq(sch->lock);
2004                 if (ret) {
2005                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2006                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
2007                                       cdev->private->dev_id.devno, ret);
2008                         ret = 0;
2009                 }
2010         }
2011
2012 out_restore:
2013         spin_unlock_irq(sch->lock);
2014         if (cdev->online && cdev->drv && cdev->drv->restore)
2015                 ret = cdev->drv->restore(cdev);
2016         return ret;
2017
2018 out_unlock:
2019         spin_unlock_irq(sch->lock);
2020         return ret;
2021 }
2022
2023 static const struct dev_pm_ops ccw_pm_ops = {
2024         .prepare = ccw_device_pm_prepare,
2025         .complete = ccw_device_pm_complete,
2026         .freeze = ccw_device_pm_freeze,
2027         .thaw = ccw_device_pm_thaw,
2028         .restore = ccw_device_pm_restore,
2029 };
2030
2031 static struct bus_type ccw_bus_type = {
2032         .name   = "ccw",
2033         .match  = ccw_bus_match,
2034         .uevent = ccw_uevent,
2035         .probe  = ccw_device_probe,
2036         .remove = ccw_device_remove,
2037         .shutdown = ccw_device_shutdown,
2038         .pm = &ccw_pm_ops,
2039 };
2040
2041 /**
2042  * ccw_driver_register() - register a ccw driver
2043  * @cdriver: driver to be registered
2044  *
2045  * This function is mainly a wrapper around driver_register().
2046  * Returns:
2047  *   %0 on success and a negative error value on failure.
2048  */
2049 int ccw_driver_register(struct ccw_driver *cdriver)
2050 {
2051         struct device_driver *drv = &cdriver->driver;
2052
2053         drv->bus = &ccw_bus_type;
2054
2055         return driver_register(drv);
2056 }
2057
2058 /**
2059  * ccw_driver_unregister() - deregister a ccw driver
2060  * @cdriver: driver to be deregistered
2061  *
2062  * This function is mainly a wrapper around driver_unregister().
2063  */
2064 void ccw_driver_unregister(struct ccw_driver *cdriver)
2065 {
2066         driver_unregister(&cdriver->driver);
2067 }
2068
2069 static void ccw_device_todo(struct work_struct *work)
2070 {
2071         struct ccw_device_private *priv;
2072         struct ccw_device *cdev;
2073         struct subchannel *sch;
2074         enum cdev_todo todo;
2075
2076         priv = container_of(work, struct ccw_device_private, todo_work);
2077         cdev = priv->cdev;
2078         sch = to_subchannel(cdev->dev.parent);
2079         /* Find out todo. */
2080         spin_lock_irq(cdev->ccwlock);
2081         todo = priv->todo;
2082         priv->todo = CDEV_TODO_NOTHING;
2083         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2084                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2085         spin_unlock_irq(cdev->ccwlock);
2086         /* Perform todo. */
2087         switch (todo) {
2088         case CDEV_TODO_ENABLE_CMF:
2089                 cmf_reenable(cdev);
2090                 break;
2091         case CDEV_TODO_REBIND:
2092                 ccw_device_do_unbind_bind(cdev);
2093                 break;
2094         case CDEV_TODO_REGISTER:
2095                 io_subchannel_register(cdev);
2096                 break;
2097         case CDEV_TODO_UNREG_EVAL:
2098                 if (!sch_is_pseudo_sch(sch))
2099                         css_schedule_eval(sch->schid);
2100                 /* fall-through */
2101         case CDEV_TODO_UNREG:
2102                 if (sch_is_pseudo_sch(sch))
2103                         ccw_device_unregister(cdev);
2104                 else
2105                         ccw_device_call_sch_unregister(cdev);
2106                 break;
2107         default:
2108                 break;
2109         }
2110         /* Release workqueue ref. */
2111         put_device(&cdev->dev);
2112 }
2113
2114 /**
2115  * ccw_device_sched_todo - schedule ccw device operation
2116  * @cdev: ccw device
2117  * @todo: todo
2118  *
2119  * Schedule the operation identified by @todo to be performed on the slow path
2120  * workqueue. Do nothing if another operation with higher priority is already
2121  * scheduled. Needs to be called with ccwdev lock held.
2122  */
2123 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2124 {
2125         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2126                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2127                       todo);
2128         if (cdev->private->todo >= todo)
2129                 return;
2130         cdev->private->todo = todo;
2131         /* Get workqueue ref. */
2132         if (!get_device(&cdev->dev))
2133                 return;
2134         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2135                 /* Already queued, release workqueue ref. */
2136                 put_device(&cdev->dev);
2137         }
2138 }
2139
2140 /**
2141  * ccw_device_siosl() - initiate logging
2142  * @cdev: ccw device
2143  *
2144  * This function is used to invoke model-dependent logging within the channel
2145  * subsystem.
2146  */
2147 int ccw_device_siosl(struct ccw_device *cdev)
2148 {
2149         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2150
2151         return chsc_siosl(sch->schid);
2152 }
2153 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2154
2155 EXPORT_SYMBOL(ccw_device_set_online);
2156 EXPORT_SYMBOL(ccw_device_set_offline);
2157 EXPORT_SYMBOL(ccw_driver_register);
2158 EXPORT_SYMBOL(ccw_driver_unregister);
2159 EXPORT_SYMBOL(get_ccwdev_by_busid);