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   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *
   5  *    Copyright IBM Corp. 2002,2008
   6  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   8  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   9  */
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/errno.h>
  14 #include <linux/err.h>
  15 #include <linux/slab.h>
  16 #include <linux/list.h>
  17 #include <linux/device.h>
  18 #include <linux/workqueue.h>
  19 #include <linux/timer.h>
  20
  21 #include <asm/ccwdev.h>
  22 #include <asm/cio.h>
  23 #include <asm/param.h>          /* HZ */
  24 #include <asm/cmb.h>
  25 #include <asm/isc.h>
  26
  27 #include "chp.h"
  28 #include "cio.h"
  29 #include "cio_debug.h"
  30 #include "css.h"
  31 #include "device.h"
  32 #include "ioasm.h"
  33 #include "io_sch.h"
  34 #include "blacklist.h"
  35
  36 static struct timer_list recovery_timer;
  37 static DEFINE_SPINLOCK(recovery_lock);
  38 static int recovery_phase;
  39 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  40
  41 /******************* bus type handling ***********************/
  42
  43 /* The Linux driver model distinguishes between a bus type and
  44  * the bus itself. Of course we only have one channel
  45  * subsystem driver and one channel system per machine, but
  46  * we still use the abstraction. T.R. says it's a good idea. */
  47 static int
  48 ccw_bus_match (struct device * dev, struct device_driver * drv)
  49 {
  50         struct ccw_device *cdev = to_ccwdev(dev);
  51         struct ccw_driver *cdrv = to_ccwdrv(drv);
  52         const struct ccw_device_id *ids = cdrv->ids, *found;
  53
  54         if (!ids)
  55                 return 0;
  56
  57         found = ccw_device_id_match(ids, &cdev->id);
  58         if (!found)
  59                 return 0;
  60
  61         cdev->id.driver_info = found->driver_info;
  62
  63         return 1;
  64 }
  65
  66 /* Store modalias string delimited by prefix/suffix string into buffer with
  67  * specified size. Return length of resulting string (excluding trailing '\0')
  68  * even if string doesn't fit buffer (snprintf semantics). */
  69 static int snprint_alias(char *buf, size_t size,
  70                          struct ccw_device_id *id, const char *suffix)
  71 {
  72         int len;
  73
  74         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  75         if (len > size)
  76                 return len;
  77         buf += len;
  78         size -= len;
  79
  80         if (id->dev_type != 0)
  81                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  82                                 id->dev_model, suffix);
  83         else
  84                 len += snprintf(buf, size, "dtdm%s", suffix);
  85
  86         return len;
  87 }
  88
  89 /* Set up environment variables for ccw device uevent. Return 0 on success,
  90  * non-zero otherwise. */
  91 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  92 {
  93         struct ccw_device *cdev = to_ccwdev(dev);
  94         struct ccw_device_id *id = &(cdev->id);
  95         int ret;
  96         char modalias_buf[30];
  97
  98         /* CU_TYPE= */
  99         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 100         if (ret)
 101                 return ret;
 102
 103         /* CU_MODEL= */
 104         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 105         if (ret)
 106                 return ret;
 107
 108         /* The next two can be zero, that's ok for us */
 109         /* DEV_TYPE= */
 110         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 111         if (ret)
 112                 return ret;
 113
 114         /* DEV_MODEL= */
 115         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 116         if (ret)
 117                 return ret;
 118
 119         /* MODALIAS=  */
 120         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 121         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 122         return ret;
 123 }
 124
 125 struct bus_type ccw_bus_type;
 126
 127 static void io_subchannel_irq(struct subchannel *);
 128 static int io_subchannel_probe(struct subchannel *);
 129 static int io_subchannel_remove(struct subchannel *);
 130 static void io_subchannel_shutdown(struct subchannel *);
 131 static int io_subchannel_sch_event(struct subchannel *, int);
 132 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 133                                    int);
 134
 135 static struct css_device_id io_subchannel_ids[] = {
 136         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 137         { /* end of list */ },
 138 };
 139 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 140
 141 static int io_subchannel_prepare(struct subchannel *sch)
 142 {
 143         struct ccw_device *cdev;
 144         /*
 145          * Don't allow suspend while a ccw device registration
 146          * is still outstanding.
 147          */
 148         cdev = sch_get_cdev(sch);
 149         if (cdev && !device_is_registered(&cdev->dev))
 150                 return -EAGAIN;
 151         return 0;
 152 }
 153
 154 static struct css_driver io_subchannel_driver = {
 155         .owner = THIS_MODULE,
 156         .subchannel_type = io_subchannel_ids,
 157         .name = "io_subchannel",
 158         .irq = io_subchannel_irq,
 159         .sch_event = io_subchannel_sch_event,
 160         .chp_event = io_subchannel_chp_event,
 161         .probe = io_subchannel_probe,
 162         .remove = io_subchannel_remove,
 163         .shutdown = io_subchannel_shutdown,
 164         .prepare = io_subchannel_prepare,
 165 };
 166
 167 struct workqueue_struct *ccw_device_work;
 168 wait_queue_head_t ccw_device_init_wq;
 169 atomic_t ccw_device_init_count;
 170
 171 static void recovery_func(unsigned long data);
 172
 173 static int __init
 174 init_ccw_bus_type (void)
 175 {
 176         int ret;
 177
 178         init_waitqueue_head(&ccw_device_init_wq);
 179         atomic_set(&ccw_device_init_count, 0);
 180         setup_timer(&recovery_timer, recovery_func, 0);
 181
 182         ccw_device_work = create_singlethread_workqueue("cio");
 183         if (!ccw_device_work)
 184                 return -ENOMEM; /* FIXME: better errno ? */
 185         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 186         if (!slow_path_wq) {
 187                 ret = -ENOMEM; /* FIXME: better errno ? */
 188                 goto out_err;
 189         }
 190         if ((ret = bus_register (&ccw_bus_type)))
 191                 goto out_err;
 192
 193         ret = css_driver_register(&io_subchannel_driver);
 194         if (ret)
 195                 goto out_err;
 196
 197         wait_event(ccw_device_init_wq,
 198                    atomic_read(&ccw_device_init_count) == 0);
 199         flush_workqueue(ccw_device_work);
 200         return 0;
 201 out_err:
 202         if (ccw_device_work)
 203                 destroy_workqueue(ccw_device_work);
 204         if (slow_path_wq)
 205                 destroy_workqueue(slow_path_wq);
 206         return ret;
 207 }
 208
 209 static void __exit
 210 cleanup_ccw_bus_type (void)
 211 {
 212         css_driver_unregister(&io_subchannel_driver);
 213         bus_unregister(&ccw_bus_type);
 214         destroy_workqueue(ccw_device_work);
 215 }
 216
 217 subsys_initcall(init_ccw_bus_type);
 218 module_exit(cleanup_ccw_bus_type);
 219
 220 /************************ device handling **************************/
 221
 222 /*
 223  * A ccw_device has some interfaces in sysfs in addition to the
 224  * standard ones.
 225  * The following entries are designed to export the information which
 226  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 227  * are obvious, so they don't have an entry :)
 228  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 229  */
 230 static ssize_t
 231 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 232 {
 233         struct subchannel *sch = to_subchannel(dev);
 234         struct chsc_ssd_info *ssd = &sch->ssd_info;
 235         ssize_t ret = 0;
 236         int chp;
 237         int mask;
 238
 239         for (chp = 0; chp < 8; chp++) {
 240                 mask = 0x80 >> chp;
 241                 if (ssd->path_mask & mask)
 242                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 243                 else
 244                         ret += sprintf(buf + ret, "00 ");
 245         }
 246         ret += sprintf (buf+ret, "\n");
 247         return min((ssize_t)PAGE_SIZE, ret);
 248 }
 249
 250 static ssize_t
 251 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 252 {
 253         struct subchannel *sch = to_subchannel(dev);
 254         struct pmcw *pmcw = &sch->schib.pmcw;
 255
 256         return sprintf (buf, "%02x %02x %02x\n",
 257                         pmcw->pim, pmcw->pam, pmcw->pom);
 258 }
 259
 260 static ssize_t
 261 devtype_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         if (id->dev_type != 0)
 267                 return sprintf(buf, "%04x/%02x\n",
 268                                 id->dev_type, id->dev_model);
 269         else
 270                 return sprintf(buf, "n/a\n");
 271 }
 272
 273 static ssize_t
 274 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 275 {
 276         struct ccw_device *cdev = to_ccwdev(dev);
 277         struct ccw_device_id *id = &(cdev->id);
 278
 279         return sprintf(buf, "%04x/%02x\n",
 280                        id->cu_type, id->cu_model);
 281 }
 282
 283 static ssize_t
 284 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 285 {
 286         struct ccw_device *cdev = to_ccwdev(dev);
 287         struct ccw_device_id *id = &(cdev->id);
 288         int len;
 289
 290         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 291
 292         return len > PAGE_SIZE ? PAGE_SIZE : len;
 293 }
 294
 295 static ssize_t
 296 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 297 {
 298         struct ccw_device *cdev = to_ccwdev(dev);
 299
 300         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 301 }
 302
 303 int ccw_device_is_orphan(struct ccw_device *cdev)
 304 {
 305         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 306 }
 307
 308 static void ccw_device_unregister(struct ccw_device *cdev)
 309 {
 310         if (test_and_clear_bit(1, &cdev->private->registered))
 311                 device_del(&cdev->dev);
 312 }
 313
 314 static void ccw_device_remove_orphan_cb(struct work_struct *work)
 315 {
 316         struct ccw_device_private *priv;
 317         struct ccw_device *cdev;
 318
 319         priv = container_of(work, struct ccw_device_private, kick_work);
 320         cdev = priv->cdev;
 321         ccw_device_unregister(cdev);
 322         put_device(&cdev->dev);
 323         /* Release cdev reference for workqueue processing. */
 324         put_device(&cdev->dev);
 325 }
 326
 327 static void
 328 ccw_device_remove_disconnected(struct ccw_device *cdev)
 329 {
 330         unsigned long flags;
 331
 332         /*
 333          * Forced offline in disconnected state means
 334          * 'throw away device'.
 335          */
 336         if (ccw_device_is_orphan(cdev)) {
 337                 /*
 338                  * Deregister ccw device.
 339                  * Unfortunately, we cannot do this directly from the
 340                  * attribute method.
 341                  */
 342                 /* Get cdev reference for workqueue processing. */
 343                 if (!get_device(&cdev->dev))
 344                         return;
 345                 spin_lock_irqsave(cdev->ccwlock, flags);
 346                 cdev->private->state = DEV_STATE_NOT_OPER;
 347                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 348                 PREPARE_WORK(&cdev->private->kick_work,
 349                                 ccw_device_remove_orphan_cb);
 350                 queue_work(slow_path_wq, &cdev->private->kick_work);
 351         } else
 352                 /* Deregister subchannel, which will kill the ccw device. */
 353                 ccw_device_schedule_sch_unregister(cdev);
 354 }
 355
 356 /**
 357  * ccw_device_set_offline() - disable a ccw device for I/O
 358  * @cdev: target ccw device
 359  *
 360  * This function calls the driver's set_offline() function for @cdev, if
 361  * given, and then disables @cdev.
 362  * Returns:
 363  *   %0 on success and a negative error value on failure.
 364  * Context:
 365  *  enabled, ccw device lock not held
 366  */
 367 int ccw_device_set_offline(struct ccw_device *cdev)
 368 {
 369         int ret;
 370
 371         if (!cdev)
 372                 return -ENODEV;
 373         if (!cdev->online || !cdev->drv)
 374                 return -EINVAL;
 375
 376         if (cdev->drv->set_offline) {
 377                 ret = cdev->drv->set_offline(cdev);
 378                 if (ret != 0)
 379                         return ret;
 380         }
 381         cdev->online = 0;
 382         spin_lock_irq(cdev->ccwlock);
 383         /* Wait until a final state or DISCONNECTED is reached */
 384         while (!dev_fsm_final_state(cdev) &&
 385                cdev->private->state != DEV_STATE_DISCONNECTED) {
 386                 spin_unlock_irq(cdev->ccwlock);
 387                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 388                            cdev->private->state == DEV_STATE_DISCONNECTED));
 389                 spin_lock_irq(cdev->ccwlock);
 390         }
 391         ret = ccw_device_offline(cdev);
 392         if (ret)
 393                 goto error;
 394         spin_unlock_irq(cdev->ccwlock);
 395         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 396                    cdev->private->state == DEV_STATE_DISCONNECTED));
 397         /* Give up reference from ccw_device_set_online(). */
 398         put_device(&cdev->dev);
 399         return 0;
 400
 401 error:
 402         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device 0.%x.%04x\n",
 403                       ret, cdev->private->dev_id.ssid,
 404                       cdev->private->dev_id.devno);
 405         cdev->private->state = DEV_STATE_OFFLINE;
 406         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 407         spin_unlock_irq(cdev->ccwlock);
 408         /* Give up reference from ccw_device_set_online(). */
 409         put_device(&cdev->dev);
 410         return -ENODEV;
 411 }
 412
 413 /**
 414  * ccw_device_set_online() - enable a ccw device for I/O
 415  * @cdev: target ccw device
 416  *
 417  * This function first enables @cdev and then calls the driver's set_online()
 418  * function for @cdev, if given. If set_online() returns an error, @cdev is
 419  * disabled again.
 420  * Returns:
 421  *   %0 on success and a negative error value on failure.
 422  * Context:
 423  *  enabled, ccw device lock not held
 424  */
 425 int ccw_device_set_online(struct ccw_device *cdev)
 426 {
 427         int ret;
 428         int ret2;
 429
 430         if (!cdev)
 431                 return -ENODEV;
 432         if (cdev->online || !cdev->drv)
 433                 return -EINVAL;
 434         /* Hold on to an extra reference while device is online. */
 435         if (!get_device(&cdev->dev))
 436                 return -ENODEV;
 437
 438         spin_lock_irq(cdev->ccwlock);
 439         ret = ccw_device_online(cdev);
 440         spin_unlock_irq(cdev->ccwlock);
 441         if (ret == 0)
 442                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 443         else {
 444                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 445                               "device 0.%x.%04x\n",
 446                               ret, cdev->private->dev_id.ssid,
 447                               cdev->private->dev_id.devno);
 448                 /* Give up online reference since onlining failed. */
 449                 put_device(&cdev->dev);
 450                 return ret;
 451         }
 452         spin_lock_irq(cdev->ccwlock);
 453         /* Check if online processing was successful */
 454         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 455             (cdev->private->state != DEV_STATE_W4SENSE)) {
 456                 spin_unlock_irq(cdev->ccwlock);
 457                 /* Give up online reference since onlining failed. */
 458                 put_device(&cdev->dev);
 459                 return -ENODEV;
 460         }
 461         spin_unlock_irq(cdev->ccwlock);
 462         if (cdev->drv->set_online)
 463                 ret = cdev->drv->set_online(cdev);
 464         if (ret)
 465                 goto rollback;
 466         cdev->online = 1;
 467         return 0;
 468
 469 rollback:
 470         spin_lock_irq(cdev->ccwlock);
 471         /* Wait until a final state or DISCONNECTED is reached */
 472         while (!dev_fsm_final_state(cdev) &&
 473                cdev->private->state != DEV_STATE_DISCONNECTED) {
 474                 spin_unlock_irq(cdev->ccwlock);
 475                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 476                            cdev->private->state == DEV_STATE_DISCONNECTED));
 477                 spin_lock_irq(cdev->ccwlock);
 478         }
 479         ret2 = ccw_device_offline(cdev);
 480         if (ret2)
 481                 goto error;
 482         spin_unlock_irq(cdev->ccwlock);
 483         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 484                    cdev->private->state == DEV_STATE_DISCONNECTED));
 485         /* Give up online reference since onlining failed. */
 486         put_device(&cdev->dev);
 487         return ret;
 488
 489 error:
 490         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 491                       "device 0.%x.%04x\n",
 492                       ret2, cdev->private->dev_id.ssid,
 493                       cdev->private->dev_id.devno);
 494         cdev->private->state = DEV_STATE_OFFLINE;
 495         spin_unlock_irq(cdev->ccwlock);
 496         /* Give up online reference since onlining failed. */
 497         put_device(&cdev->dev);
 498         return ret;
 499 }
 500
 501 static int online_store_handle_offline(struct ccw_device *cdev)
 502 {
 503         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 504                 ccw_device_remove_disconnected(cdev);
 505         else if (cdev->online && cdev->drv && cdev->drv->set_offline)
 506                 return ccw_device_set_offline(cdev);
 507         return 0;
 508 }
 509
 510 static int online_store_recog_and_online(struct ccw_device *cdev)
 511 {
 512         int ret;
 513
 514         /* Do device recognition, if needed. */
 515         if (cdev->private->state == DEV_STATE_BOXED) {
 516                 ret = ccw_device_recognition(cdev);
 517                 if (ret) {
 518                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 519                                       "for device 0.%x.%04x (ret=%d)\n",
 520                                       cdev->private->dev_id.ssid,
 521                                       cdev->private->dev_id.devno, ret);
 522                         return ret;
 523                 }
 524                 wait_event(cdev->private->wait_q,
 525                            cdev->private->flags.recog_done);
 526                 if (cdev->private->state != DEV_STATE_OFFLINE)
 527                         /* recognition failed */
 528                         return -EAGAIN;
 529         }
 530         if (cdev->drv && cdev->drv->set_online)
 531                 ccw_device_set_online(cdev);
 532         return 0;
 533 }
 534
 535 static int online_store_handle_online(struct ccw_device *cdev, int force)
 536 {
 537         int ret;
 538
 539         ret = online_store_recog_and_online(cdev);
 540         if (ret && !force)
 541                 return ret;
 542         if (force && cdev->private->state == DEV_STATE_BOXED) {
 543                 ret = ccw_device_stlck(cdev);
 544                 if (ret)
 545                         return ret;
 546                 if (cdev->id.cu_type == 0)
 547                         cdev->private->state = DEV_STATE_NOT_OPER;
 548                 ret = online_store_recog_and_online(cdev);
 549                 if (ret)
 550                         return ret;
 551         }
 552         return 0;
 553 }
 554
 555 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 556                              const char *buf, size_t count)
 557 {
 558         struct ccw_device *cdev = to_ccwdev(dev);
 559         int force, ret;
 560         unsigned long i;
 561
 562         if ((cdev->private->state != DEV_STATE_OFFLINE &&
 563              cdev->private->state != DEV_STATE_ONLINE &&
 564              cdev->private->state != DEV_STATE_BOXED &&
 565              cdev->private->state != DEV_STATE_DISCONNECTED) ||
 566             atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 567                 return -EAGAIN;
 568
 569         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 570                 atomic_set(&cdev->private->onoff, 0);
 571                 return -EINVAL;
 572         }
 573         if (!strncmp(buf, "force\n", count)) {
 574                 force = 1;
 575                 i = 1;
 576                 ret = 0;
 577         } else {
 578                 force = 0;
 579                 ret = strict_strtoul(buf, 16, &i);
 580         }
 581         if (ret)
 582                 goto out;
 583         switch (i) {
 584         case 0:
 585                 ret = online_store_handle_offline(cdev);
 586                 break;
 587         case 1:
 588                 ret = online_store_handle_online(cdev, force);
 589                 break;
 590         default:
 591                 ret = -EINVAL;
 592         }
 593 out:
 594         if (cdev->drv)
 595                 module_put(cdev->drv->owner);
 596         atomic_set(&cdev->private->onoff, 0);
 597         return (ret < 0) ? ret : count;
 598 }
 599
 600 static ssize_t
 601 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 602 {
 603         struct ccw_device *cdev = to_ccwdev(dev);
 604         struct subchannel *sch;
 605
 606         if (ccw_device_is_orphan(cdev))
 607                 return sprintf(buf, "no device\n");
 608         switch (cdev->private->state) {
 609         case DEV_STATE_BOXED:
 610                 return sprintf(buf, "boxed\n");
 611         case DEV_STATE_DISCONNECTED:
 612         case DEV_STATE_DISCONNECTED_SENSE_ID:
 613         case DEV_STATE_NOT_OPER:
 614                 sch = to_subchannel(dev->parent);
 615                 if (!sch->lpm)
 616                         return sprintf(buf, "no path\n");
 617                 else
 618                         return sprintf(buf, "no device\n");
 619         default:
 620                 /* All other states considered fine. */
 621                 return sprintf(buf, "good\n");
 622         }
 623 }
 624
 625 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 626 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 627 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 628 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 629 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 630 static DEVICE_ATTR(online, 0644, online_show, online_store);
 631 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 632
 633 static struct attribute *io_subchannel_attrs[] = {
 634         &dev_attr_chpids.attr,
 635         &dev_attr_pimpampom.attr,
 636         NULL,
 637 };
 638
 639 static struct attribute_group io_subchannel_attr_group = {
 640         .attrs = io_subchannel_attrs,
 641 };
 642
 643 static struct attribute * ccwdev_attrs[] = {
 644         &dev_attr_devtype.attr,
 645         &dev_attr_cutype.attr,
 646         &dev_attr_modalias.attr,
 647         &dev_attr_online.attr,
 648         &dev_attr_cmb_enable.attr,
 649         &dev_attr_availability.attr,
 650         NULL,
 651 };
 652
 653 static struct attribute_group ccwdev_attr_group = {
 654         .attrs = ccwdev_attrs,
 655 };
 656
 657 static struct attribute_group *ccwdev_attr_groups[] = {
 658         &ccwdev_attr_group,
 659         NULL,
 660 };
 661
 662 /* this is a simple abstraction for device_register that sets the
 663  * correct bus type and adds the bus specific files */
 664 static int ccw_device_register(struct ccw_device *cdev)
 665 {
 666         struct device *dev = &cdev->dev;
 667         int ret;
 668
 669         dev->bus = &ccw_bus_type;
 670
 671         if ((ret = device_add(dev)))
 672                 return ret;
 673
 674         set_bit(1, &cdev->private->registered);
 675         return ret;
 676 }
 677
 678 struct match_data {
 679         struct ccw_dev_id dev_id;
 680         struct ccw_device * sibling;
 681 };
 682
 683 static int
 684 match_devno(struct device * dev, void * data)
 685 {
 686         struct match_data * d = data;
 687         struct ccw_device * cdev;
 688
 689         cdev = to_ccwdev(dev);
 690         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 691             !ccw_device_is_orphan(cdev) &&
 692             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 693             (cdev != d->sibling))
 694                 return 1;
 695         return 0;
 696 }
 697
 698 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 699                                                      struct ccw_device *sibling)
 700 {
 701         struct device *dev;
 702         struct match_data data;
 703
 704         data.dev_id = *dev_id;
 705         data.sibling = sibling;
 706         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 707
 708         return dev ? to_ccwdev(dev) : NULL;
 709 }
 710
 711 static int match_orphan(struct device *dev, void *data)
 712 {
 713         struct ccw_dev_id *dev_id;
 714         struct ccw_device *cdev;
 715
 716         dev_id = data;
 717         cdev = to_ccwdev(dev);
 718         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 719 }
 720
 721 static struct ccw_device *
 722 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 723                               struct ccw_dev_id *dev_id)
 724 {
 725         struct device *dev;
 726
 727         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 728                                 match_orphan);
 729
 730         return dev ? to_ccwdev(dev) : NULL;
 731 }
 732
 733 void ccw_device_do_unbind_bind(struct work_struct *work)
 734 {
 735         struct ccw_device_private *priv;
 736         struct ccw_device *cdev;
 737         struct subchannel *sch;
 738         int ret;
 739
 740         priv = container_of(work, struct ccw_device_private, kick_work);
 741         cdev = priv->cdev;
 742         sch = to_subchannel(cdev->dev.parent);
 743
 744         if (test_bit(1, &cdev->private->registered)) {
 745                 device_release_driver(&cdev->dev);
 746                 ret = device_attach(&cdev->dev);
 747                 WARN_ON(ret == -ENODEV);
 748         }
 749 }
 750
 751 static void
 752 ccw_device_release(struct device *dev)
 753 {
 754         struct ccw_device *cdev;
 755
 756         cdev = to_ccwdev(dev);
 757         /* Release reference of parent subchannel. */
 758         put_device(cdev->dev.parent);
 759         kfree(cdev->private);
 760         kfree(cdev);
 761 }
 762
 763 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 764 {
 765         struct ccw_device *cdev;
 766
 767         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 768         if (cdev) {
 769                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 770                                         GFP_KERNEL | GFP_DMA);
 771                 if (cdev->private)
 772                         return cdev;
 773         }
 774         kfree(cdev);
 775         return ERR_PTR(-ENOMEM);
 776 }
 777
 778 static int io_subchannel_initialize_dev(struct subchannel *sch,
 779                                         struct ccw_device *cdev)
 780 {
 781         cdev->private->cdev = cdev;
 782         atomic_set(&cdev->private->onoff, 0);
 783         cdev->dev.parent = &sch->dev;
 784         cdev->dev.release = ccw_device_release;
 785         INIT_WORK(&cdev->private->kick_work, NULL);
 786         cdev->dev.groups = ccwdev_attr_groups;
 787         /* Do first half of device_register. */
 788         device_initialize(&cdev->dev);
 789         if (!get_device(&sch->dev)) {
 790                 /* Release reference from device_initialize(). */
 791                 put_device(&cdev->dev);
 792                 return -ENODEV;
 793         }
 794         return 0;
 795 }
 796
 797 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 798 {
 799         struct ccw_device *cdev;
 800         int ret;
 801
 802         cdev = io_subchannel_allocate_dev(sch);
 803         if (!IS_ERR(cdev)) {
 804                 ret = io_subchannel_initialize_dev(sch, cdev);
 805                 if (ret)
 806                         cdev = ERR_PTR(ret);
 807         }
 808         return cdev;
 809 }
 810
 811 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 812
 813 static void sch_attach_device(struct subchannel *sch,
 814                               struct ccw_device *cdev)
 815 {
 816         css_update_ssd_info(sch);
 817         spin_lock_irq(sch->lock);
 818         sch_set_cdev(sch, cdev);
 819         cdev->private->schid = sch->schid;
 820         cdev->ccwlock = sch->lock;
 821         ccw_device_trigger_reprobe(cdev);
 822         spin_unlock_irq(sch->lock);
 823 }
 824
 825 static void sch_attach_disconnected_device(struct subchannel *sch,
 826                                            struct ccw_device *cdev)
 827 {
 828         struct subchannel *other_sch;
 829         int ret;
 830
 831         /* Get reference for new parent. */
 832         if (!get_device(&sch->dev))
 833                 return;
 834         other_sch = to_subchannel(cdev->dev.parent);
 835         /* Note: device_move() changes cdev->dev.parent */
 836         ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 837         if (ret) {
 838                 CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
 839                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 840                               cdev->private->dev_id.devno, ret);
 841                 /* Put reference for new parent. */
 842                 put_device(&sch->dev);
 843                 return;
 844         }
 845         sch_set_cdev(other_sch, NULL);
 846         /* No need to keep a subchannel without ccw device around. */
 847         css_sch_device_unregister(other_sch);
 848         sch_attach_device(sch, cdev);
 849         /* Put reference for old parent. */
 850         put_device(&other_sch->dev);
 851 }
 852
 853 static void sch_attach_orphaned_device(struct subchannel *sch,
 854                                        struct ccw_device *cdev)
 855 {
 856         int ret;
 857         struct subchannel *pseudo_sch;
 858
 859         /* Get reference for new parent. */
 860         if (!get_device(&sch->dev))
 861                 return;
 862         pseudo_sch = to_subchannel(cdev->dev.parent);
 863         /*
 864          * Try to move the ccw device to its new subchannel.
 865          * Note: device_move() changes cdev->dev.parent
 866          */
 867         ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 868         if (ret) {
 869                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 870                               "failed (ret=%d)!\n",
 871                               cdev->private->dev_id.ssid,
 872                               cdev->private->dev_id.devno, ret);
 873                 /* Put reference for new parent. */
 874                 put_device(&sch->dev);
 875                 return;
 876         }
 877         sch_attach_device(sch, cdev);
 878         /* Put reference on pseudo subchannel. */
 879         put_device(&pseudo_sch->dev);
 880 }
 881
 882 static void sch_create_and_recog_new_device(struct subchannel *sch)
 883 {
 884         struct ccw_device *cdev;
 885
 886         /* Need to allocate a new ccw device. */
 887         cdev = io_subchannel_create_ccwdev(sch);
 888         if (IS_ERR(cdev)) {
 889                 /* OK, we did everything we could... */
 890                 css_sch_device_unregister(sch);
 891                 return;
 892         }
 893         spin_lock_irq(sch->lock);
 894         sch_set_cdev(sch, cdev);
 895         spin_unlock_irq(sch->lock);
 896         /* Start recognition for the new ccw device. */
 897         if (io_subchannel_recog(cdev, sch)) {
 898                 spin_lock_irq(sch->lock);
 899                 sch_set_cdev(sch, NULL);
 900                 spin_unlock_irq(sch->lock);
 901                 css_sch_device_unregister(sch);
 902                 /* Put reference from io_subchannel_create_ccwdev(). */
 903                 put_device(&sch->dev);
 904                 /* Give up initial reference. */
 905                 put_device(&cdev->dev);
 906         }
 907 }
 908
 909
 910 void ccw_device_move_to_orphanage(struct work_struct *work)
 911 {
 912         struct ccw_device_private *priv;
 913         struct ccw_device *cdev;
 914         struct ccw_device *replacing_cdev;
 915         struct subchannel *sch;
 916         int ret;
 917         struct channel_subsystem *css;
 918         struct ccw_dev_id dev_id;
 919
 920         priv = container_of(work, struct ccw_device_private, kick_work);
 921         cdev = priv->cdev;
 922         sch = to_subchannel(cdev->dev.parent);
 923         css = to_css(sch->dev.parent);
 924         dev_id.devno = sch->schib.pmcw.dev;
 925         dev_id.ssid = sch->schid.ssid;
 926
 927         /* Increase refcount for pseudo subchannel. */
 928         get_device(&css->pseudo_subchannel->dev);
 929         /*
 930          * Move the orphaned ccw device to the orphanage so the replacing
 931          * ccw device can take its place on the subchannel.
 932          * Note: device_move() changes cdev->dev.parent
 933          */
 934         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev,
 935                 DPM_ORDER_NONE);
 936         if (ret) {
 937                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 938                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 939                               cdev->private->dev_id.devno, ret);
 940                 /* Decrease refcount for pseudo subchannel again. */
 941                 put_device(&css->pseudo_subchannel->dev);
 942                 return;
 943         }
 944         cdev->ccwlock = css->pseudo_subchannel->lock;
 945         /*
 946          * Search for the replacing ccw device
 947          * - among the disconnected devices
 948          * - in the orphanage
 949          */
 950         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 951         if (replacing_cdev) {
 952                 sch_attach_disconnected_device(sch, replacing_cdev);
 953                 /* Release reference from get_disc_ccwdev_by_dev_id() */
 954                 put_device(&replacing_cdev->dev);
 955                 /* Release reference of subchannel from old cdev. */
 956                 put_device(&sch->dev);
 957                 return;
 958         }
 959         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 960         if (replacing_cdev) {
 961                 sch_attach_orphaned_device(sch, replacing_cdev);
 962                 /* Release reference from get_orphaned_ccwdev_by_dev_id() */
 963                 put_device(&replacing_cdev->dev);
 964                 /* Release reference of subchannel from old cdev. */
 965                 put_device(&sch->dev);
 966                 return;
 967         }
 968         sch_create_and_recog_new_device(sch);
 969         /* Release reference of subchannel from old cdev. */
 970         put_device(&sch->dev);
 971 }
 972
 973 /*
 974  * Register recognized device.
 975  */
 976 static void
 977 io_subchannel_register(struct work_struct *work)
 978 {
 979         struct ccw_device_private *priv;
 980         struct ccw_device *cdev;
 981         struct subchannel *sch;
 982         int ret;
 983         unsigned long flags;
 984
 985         priv = container_of(work, struct ccw_device_private, kick_work);
 986         cdev = priv->cdev;
 987         sch = to_subchannel(cdev->dev.parent);
 988         /*
 989          * Check if subchannel is still registered. It may have become
 990          * unregistered if a machine check hit us after finishing
 991          * device recognition but before the register work could be
 992          * queued.
 993          */
 994         if (!device_is_registered(&sch->dev))
 995                 goto out_err;
 996         css_update_ssd_info(sch);
 997         /*
 998          * io_subchannel_register() will also be called after device
 999          * recognition has been done for a boxed device (which will already
1000          * be registered). We need to reprobe since we may now have sense id
1001          * information.
1002          */
1003         if (device_is_registered(&cdev->dev)) {
1004                 if (!cdev->drv) {
1005                         ret = device_reprobe(&cdev->dev);
1006                         if (ret)
1007                                 /* We can't do much here. */
1008                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
1009                                               " %d for 0.%x.%04x\n", ret,
1010                                               cdev->private->dev_id.ssid,
1011                                               cdev->private->dev_id.devno);
1012                 }
1013                 goto out;
1014         }
1015         /*
1016          * Now we know this subchannel will stay, we can throw
1017          * our delayed uevent.
1018          */
1019         dev_set_uevent_suppress(&sch->dev, 0);
1020         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1021         /* make it known to the system */
1022         ret = ccw_device_register(cdev);
1023         if (ret) {
1024                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
1025                               cdev->private->dev_id.ssid,
1026                               cdev->private->dev_id.devno, ret);
1027                 spin_lock_irqsave(sch->lock, flags);
1028                 sch_set_cdev(sch, NULL);
1029                 spin_unlock_irqrestore(sch->lock, flags);
1030                 /* Release initial device reference. */
1031                 put_device(&cdev->dev);
1032                 goto out_err;
1033         }
1034 out:
1035         cdev->private->flags.recog_done = 1;
1036         wake_up(&cdev->private->wait_q);
1037 out_err:
1038         /* Release reference for workqueue processing. */
1039         put_device(&cdev->dev);
1040         if (atomic_dec_and_test(&ccw_device_init_count))
1041                 wake_up(&ccw_device_init_wq);
1042 }
1043
1044 static void ccw_device_call_sch_unregister(struct work_struct *work)
1045 {
1046         struct ccw_device_private *priv;
1047         struct ccw_device *cdev;
1048         struct subchannel *sch;
1049
1050         priv = container_of(work, struct ccw_device_private, kick_work);
1051         cdev = priv->cdev;
1052         /* Get subchannel reference for local processing. */
1053         if (!get_device(cdev->dev.parent))
1054                 return;
1055         sch = to_subchannel(cdev->dev.parent);
1056         css_sch_device_unregister(sch);
1057         /* Release cdev reference for workqueue processing.*/
1058         put_device(&cdev->dev);
1059         /* Release subchannel reference for local processing. */
1060         put_device(&sch->dev);
1061 }
1062
1063 void ccw_device_schedule_sch_unregister(struct ccw_device *cdev)
1064 {
1065         /* Get cdev reference for workqueue processing. */
1066         if (!get_device(&cdev->dev))
1067                 return;
1068         PREPARE_WORK(&cdev->private->kick_work,
1069                      ccw_device_call_sch_unregister);
1070         queue_work(slow_path_wq, &cdev->private->kick_work);
1071 }
1072
1073 /*
1074  * subchannel recognition done. Called from the state machine.
1075  */
1076 void
1077 io_subchannel_recog_done(struct ccw_device *cdev)
1078 {
1079         if (css_init_done == 0) {
1080                 cdev->private->flags.recog_done = 1;
1081                 return;
1082         }
1083         switch (cdev->private->state) {
1084         case DEV_STATE_BOXED:
1085                 /* Device did not respond in time. */
1086         case DEV_STATE_NOT_OPER:
1087                 cdev->private->flags.recog_done = 1;
1088                 ccw_device_schedule_sch_unregister(cdev);
1089                 if (atomic_dec_and_test(&ccw_device_init_count))
1090                         wake_up(&ccw_device_init_wq);
1091                 break;
1092         case DEV_STATE_OFFLINE:
1093                 /*
1094                  * We can't register the device in interrupt context so
1095                  * we schedule a work item.
1096                  */
1097                 if (!get_device(&cdev->dev))
1098                         break;
1099                 PREPARE_WORK(&cdev->private->kick_work,
1100                              io_subchannel_register);
1101                 queue_work(slow_path_wq, &cdev->private->kick_work);
1102                 break;
1103         }
1104 }
1105
1106 static int
1107 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1108 {
1109         int rc;
1110         struct ccw_device_private *priv;
1111
1112         sch_set_cdev(sch, cdev);
1113         cdev->ccwlock = sch->lock;
1114
1115         /* Init private data. */
1116         priv = cdev->private;
1117         priv->dev_id.devno = sch->schib.pmcw.dev;
1118         priv->dev_id.ssid = sch->schid.ssid;
1119         priv->schid = sch->schid;
1120         priv->state = DEV_STATE_NOT_OPER;
1121         INIT_LIST_HEAD(&priv->cmb_list);
1122         init_waitqueue_head(&priv->wait_q);
1123         init_timer(&priv->timer);
1124
1125         /* Set an initial name for the device. */
1126         if (cio_is_console(sch->schid))
1127                 cdev->dev.init_name = cio_get_console_cdev_name(sch);
1128         else
1129                 dev_set_name(&cdev->dev, "0.%x.%04x",
1130                              sch->schid.ssid, sch->schib.pmcw.dev);
1131
1132         /* Increase counter of devices currently in recognition. */
1133         atomic_inc(&ccw_device_init_count);
1134
1135         /* Start async. device sensing. */
1136         spin_lock_irq(sch->lock);
1137         rc = ccw_device_recognition(cdev);
1138         spin_unlock_irq(sch->lock);
1139         if (rc) {
1140                 if (atomic_dec_and_test(&ccw_device_init_count))
1141                         wake_up(&ccw_device_init_wq);
1142         }
1143         return rc;
1144 }
1145
1146 static void ccw_device_move_to_sch(struct work_struct *work)
1147 {
1148         struct ccw_device_private *priv;
1149         int rc;
1150         struct subchannel *sch;
1151         struct ccw_device *cdev;
1152         struct subchannel *former_parent;
1153
1154         priv = container_of(work, struct ccw_device_private, kick_work);
1155         sch = priv->sch;
1156         cdev = priv->cdev;
1157         former_parent = to_subchannel(cdev->dev.parent);
1158         /* Get reference for new parent. */
1159         if (!get_device(&sch->dev))
1160                 return;
1161         mutex_lock(&sch->reg_mutex);
1162         /*
1163          * Try to move the ccw device to its new subchannel.
1164          * Note: device_move() changes cdev->dev.parent
1165          */
1166         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
1167         mutex_unlock(&sch->reg_mutex);
1168         if (rc) {
1169                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
1170                               "0.%x.%04x failed (ret=%d)!\n",
1171                               cdev->private->dev_id.ssid,
1172                               cdev->private->dev_id.devno, sch->schid.ssid,
1173                               sch->schid.sch_no, rc);
1174                 css_sch_device_unregister(sch);
1175                 /* Put reference for new parent again. */
1176                 put_device(&sch->dev);
1177                 goto out;
1178         }
1179         if (!sch_is_pseudo_sch(former_parent)) {
1180                 spin_lock_irq(former_parent->lock);
1181                 sch_set_cdev(former_parent, NULL);
1182                 spin_unlock_irq(former_parent->lock);
1183                 css_sch_device_unregister(former_parent);
1184                 /* Reset intparm to zeroes. */
1185                 former_parent->config.intparm = 0;
1186                 cio_commit_config(former_parent);
1187         }
1188         sch_attach_device(sch, cdev);
1189 out:
1190         /* Put reference for old parent. */
1191         put_device(&former_parent->dev);
1192         put_device(&cdev->dev);
1193 }
1194
1195 static void io_subchannel_irq(struct subchannel *sch)
1196 {
1197         struct ccw_device *cdev;
1198
1199         cdev = sch_get_cdev(sch);
1200
1201         CIO_TRACE_EVENT(6, "IRQ");
1202         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1203         if (cdev)
1204                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1205 }
1206
1207 void io_subchannel_init_config(struct subchannel *sch)
1208 {
1209         memset(&sch->config, 0, sizeof(sch->config));
1210         sch->config.csense = 1;
1211         /* Use subchannel mp mode when there is more than 1 installed CHPID. */
1212         if ((sch->schib.pmcw.pim & (sch->schib.pmcw.pim - 1)) != 0)
1213                 sch->config.mp = 1;
1214 }
1215
1216 static void io_subchannel_init_fields(struct subchannel *sch)
1217 {
1218         if (cio_is_console(sch->schid))
1219                 sch->opm = 0xff;
1220         else
1221                 sch->opm = chp_get_sch_opm(sch);
1222         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1223         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1224
1225         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1226                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1227                       sch->schib.pmcw.dev, sch->schid.ssid,
1228                       sch->schid.sch_no, sch->schib.pmcw.pim,
1229                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1230
1231         io_subchannel_init_config(sch);
1232 }
1233
1234 static void io_subchannel_do_unreg(struct work_struct *work)
1235 {
1236         struct subchannel *sch;
1237
1238         sch = container_of(work, struct subchannel, work);
1239         css_sch_device_unregister(sch);
1240         put_device(&sch->dev);
1241 }
1242
1243 /* Schedule unregister if we have no cdev. */
1244 static void io_subchannel_schedule_removal(struct subchannel *sch)
1245 {
1246         get_device(&sch->dev);
1247         INIT_WORK(&sch->work, io_subchannel_do_unreg);
1248         queue_work(slow_path_wq, &sch->work);
1249 }
1250
1251 /*
1252  * Note: We always return 0 so that we bind to the device even on error.
1253  * This is needed so that our remove function is called on unregister.
1254  */
1255 static int io_subchannel_probe(struct subchannel *sch)
1256 {
1257         struct ccw_device *cdev;
1258         int rc;
1259         unsigned long flags;
1260         struct ccw_dev_id dev_id;
1261
1262         cdev = sch_get_cdev(sch);
1263         if (cdev) {
1264                 rc = sysfs_create_group(&sch->dev.kobj,
1265                                         &io_subchannel_attr_group);
1266                 if (rc)
1267                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1268                                       "attributes for subchannel "
1269                                       "0.%x.%04x (rc=%d)\n",
1270                                       sch->schid.ssid, sch->schid.sch_no, rc);
1271                 /*
1272                  * This subchannel already has an associated ccw_device.
1273                  * Throw the delayed uevent for the subchannel, register
1274                  * the ccw_device and exit. This happens for all early
1275                  * devices, e.g. the console.
1276                  */
1277                 dev_set_uevent_suppress(&sch->dev, 0);
1278                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1279                 cdev->dev.groups = ccwdev_attr_groups;
1280                 device_initialize(&cdev->dev);
1281                 ccw_device_register(cdev);
1282                 /*
1283                  * Check if the device is already online. If it is
1284                  * the reference count needs to be corrected since we
1285                  * didn't obtain a reference in ccw_device_set_online.
1286                  */
1287                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1288                     cdev->private->state != DEV_STATE_OFFLINE &&
1289                     cdev->private->state != DEV_STATE_BOXED)
1290                         get_device(&cdev->dev);
1291                 return 0;
1292         }
1293         io_subchannel_init_fields(sch);
1294         rc = cio_commit_config(sch);
1295         if (rc)
1296                 goto out_schedule;
1297         rc = sysfs_create_group(&sch->dev.kobj,
1298                                 &io_subchannel_attr_group);
1299         if (rc)
1300                 goto out_schedule;
1301         /* Allocate I/O subchannel private data. */
1302         sch->private = kzalloc(sizeof(struct io_subchannel_private),
1303                                GFP_KERNEL | GFP_DMA);
1304         if (!sch->private)
1305                 goto out_err;
1306         /*
1307          * First check if a fitting device may be found amongst the
1308          * disconnected devices or in the orphanage.
1309          */
1310         dev_id.devno = sch->schib.pmcw.dev;
1311         dev_id.ssid = sch->schid.ssid;
1312         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1313         if (!cdev)
1314                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1315                                                      &dev_id);
1316         if (cdev) {
1317                 /*
1318                  * Schedule moving the device until when we have a registered
1319                  * subchannel to move to and succeed the probe. We can
1320                  * unregister later again, when the probe is through.
1321                  */
1322                 cdev->private->sch = sch;
1323                 PREPARE_WORK(&cdev->private->kick_work,
1324                              ccw_device_move_to_sch);
1325                 queue_work(slow_path_wq, &cdev->private->kick_work);
1326                 return 0;
1327         }
1328         cdev = io_subchannel_create_ccwdev(sch);
1329         if (IS_ERR(cdev))
1330                 goto out_err;
1331         rc = io_subchannel_recog(cdev, sch);
1332         if (rc) {
1333                 spin_lock_irqsave(sch->lock, flags);
1334                 io_subchannel_recog_done(cdev);
1335                 spin_unlock_irqrestore(sch->lock, flags);
1336         }
1337         return 0;
1338 out_err:
1339         kfree(sch->private);
1340         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1341 out_schedule:
1342         io_subchannel_schedule_removal(sch);
1343         return 0;
1344 }
1345
1346 static int
1347 io_subchannel_remove (struct subchannel *sch)
1348 {
1349         struct ccw_device *cdev;
1350         unsigned long flags;
1351
1352         cdev = sch_get_cdev(sch);
1353         if (!cdev)
1354                 return 0;
1355         /* Set ccw device to not operational and drop reference. */
1356         spin_lock_irqsave(cdev->ccwlock, flags);
1357         sch_set_cdev(sch, NULL);
1358         cdev->private->state = DEV_STATE_NOT_OPER;
1359         spin_unlock_irqrestore(cdev->ccwlock, flags);
1360         ccw_device_unregister(cdev);
1361         put_device(&cdev->dev);
1362         kfree(sch->private);
1363         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1364         return 0;
1365 }
1366
1367 static int io_subchannel_notify(struct subchannel *sch, int event)
1368 {
1369         struct ccw_device *cdev;
1370
1371         cdev = sch_get_cdev(sch);
1372         if (!cdev)
1373                 return 0;
1374         return ccw_device_notify(cdev, event);
1375 }
1376
1377 static void io_subchannel_verify(struct subchannel *sch)
1378 {
1379         struct ccw_device *cdev;
1380
1381         cdev = sch_get_cdev(sch);
1382         if (cdev)
1383                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1384 }
1385
1386 static int check_for_io_on_path(struct subchannel *sch, int mask)
1387 {
1388         if (cio_update_schib(sch))
1389                 return 0;
1390         if (scsw_actl(&sch->schib.scsw) && sch->schib.pmcw.lpum == mask)
1391                 return 1;
1392         return 0;
1393 }
1394
1395 static void terminate_internal_io(struct subchannel *sch,
1396                                   struct ccw_device *cdev)
1397 {
1398         if (cio_clear(sch)) {
1399                 /* Recheck device in case clear failed. */
1400                 sch->lpm = 0;
1401                 if (cdev->online)
1402                         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1403                 else
1404                         css_schedule_eval(sch->schid);
1405                 return;
1406         }
1407         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1408         /* Request retry of internal operation. */
1409         cdev->private->flags.intretry = 1;
1410         /* Call handler. */
1411         if (cdev->handler)
1412                 cdev->handler(cdev, cdev->private->intparm,
1413                               ERR_PTR(-EIO));
1414 }
1415
1416 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1417 {
1418         struct ccw_device *cdev;
1419
1420         cdev = sch_get_cdev(sch);
1421         if (!cdev)
1422                 return;
1423         if (check_for_io_on_path(sch, mask)) {
1424                 if (cdev->private->state == DEV_STATE_ONLINE)
1425                         ccw_device_kill_io(cdev);
1426                 else {
1427                         terminate_internal_io(sch, cdev);
1428                         /* Re-start path verification. */
1429                         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1430                 }
1431         } else
1432                 /* trigger path verification. */
1433                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1434
1435 }
1436
1437 static int io_subchannel_chp_event(struct subchannel *sch,
1438                                    struct chp_link *link, int event)
1439 {
1440         int mask;
1441
1442         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1443         if (!mask)
1444                 return 0;
1445         switch (event) {
1446         case CHP_VARY_OFF:
1447                 sch->opm &= ~mask;
1448                 sch->lpm &= ~mask;
1449                 io_subchannel_terminate_path(sch, mask);
1450                 break;
1451         case CHP_VARY_ON:
1452                 sch->opm |= mask;
1453                 sch->lpm |= mask;
1454                 io_subchannel_verify(sch);
1455                 break;
1456         case CHP_OFFLINE:
1457                 if (cio_update_schib(sch))
1458                         return -ENODEV;
1459                 io_subchannel_terminate_path(sch, mask);
1460                 break;
1461         case CHP_ONLINE:
1462                 if (cio_update_schib(sch))
1463                         return -ENODEV;
1464                 sch->lpm |= mask & sch->opm;
1465                 io_subchannel_verify(sch);
1466                 break;
1467         }
1468         return 0;
1469 }
1470
1471 static void
1472 io_subchannel_shutdown(struct subchannel *sch)
1473 {
1474         struct ccw_device *cdev;
1475         int ret;
1476
1477         cdev = sch_get_cdev(sch);
1478
1479         if (cio_is_console(sch->schid))
1480                 return;
1481         if (!sch->schib.pmcw.ena)
1482                 /* Nothing to do. */
1483                 return;
1484         ret = cio_disable_subchannel(sch);
1485         if (ret != -EBUSY)
1486                 /* Subchannel is disabled, we're done. */
1487                 return;
1488         cdev->private->state = DEV_STATE_QUIESCE;
1489         if (cdev->handler)
1490                 cdev->handler(cdev, cdev->private->intparm,
1491                               ERR_PTR(-EIO));
1492         ret = ccw_device_cancel_halt_clear(cdev);
1493         if (ret == -EBUSY) {
1494                 ccw_device_set_timeout(cdev, HZ/10);
1495                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1496         }
1497         cio_disable_subchannel(sch);
1498 }
1499
1500 static int io_subchannel_get_status(struct subchannel *sch)
1501 {
1502         struct schib schib;
1503
1504         if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
1505                 return CIO_GONE;
1506         if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
1507                 return CIO_REVALIDATE;
1508         if (!sch->lpm)
1509                 return CIO_NO_PATH;
1510         return CIO_OPER;
1511 }
1512
1513 static int device_is_disconnected(struct ccw_device *cdev)
1514 {
1515         if (!cdev)
1516                 return 0;
1517         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1518                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1519 }
1520
1521 static int recovery_check(struct device *dev, void *data)
1522 {
1523         struct ccw_device *cdev = to_ccwdev(dev);
1524         int *redo = data;
1525
1526         spin_lock_irq(cdev->ccwlock);
1527         switch (cdev->private->state) {
1528         case DEV_STATE_DISCONNECTED:
1529                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1530                               cdev->private->dev_id.ssid,
1531                               cdev->private->dev_id.devno);
1532                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1533                 *redo = 1;
1534                 break;
1535         case DEV_STATE_DISCONNECTED_SENSE_ID:
1536                 *redo = 1;
1537                 break;
1538         }
1539         spin_unlock_irq(cdev->ccwlock);
1540
1541         return 0;
1542 }
1543
1544 static void recovery_work_func(struct work_struct *unused)
1545 {
1546         int redo = 0;
1547
1548         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1549         if (redo) {
1550                 spin_lock_irq(&recovery_lock);
1551                 if (!timer_pending(&recovery_timer)) {
1552                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1553                                 recovery_phase++;
1554                         mod_timer(&recovery_timer, jiffies +
1555                                   recovery_delay[recovery_phase] * HZ);
1556                 }
1557                 spin_unlock_irq(&recovery_lock);
1558         } else
1559                 CIO_MSG_EVENT(4, "recovery: end\n");
1560 }
1561
1562 static DECLARE_WORK(recovery_work, recovery_work_func);
1563
1564 static void recovery_func(unsigned long data)
1565 {
1566         /*
1567          * We can't do our recovery in softirq context and it's not
1568          * performance critical, so we schedule it.
1569          */
1570         schedule_work(&recovery_work);
1571 }
1572
1573 static void ccw_device_schedule_recovery(void)
1574 {
1575         unsigned long flags;
1576
1577         CIO_MSG_EVENT(4, "recovery: schedule\n");
1578         spin_lock_irqsave(&recovery_lock, flags);
1579         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1580                 recovery_phase = 0;
1581                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1582         }
1583         spin_unlock_irqrestore(&recovery_lock, flags);
1584 }
1585
1586 static int purge_fn(struct device *dev, void *data)
1587 {
1588         struct ccw_device *cdev = to_ccwdev(dev);
1589         struct ccw_device_private *priv = cdev->private;
1590         int unreg;
1591
1592         spin_lock_irq(cdev->ccwlock);
1593         unreg = is_blacklisted(priv->dev_id.ssid, priv->dev_id.devno) &&
1594                 (priv->state == DEV_STATE_OFFLINE);
1595         spin_unlock_irq(cdev->ccwlock);
1596         if (!unreg)
1597                 goto out;
1598         CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", priv->dev_id.ssid,
1599                       priv->dev_id.devno);
1600         ccw_device_schedule_sch_unregister(cdev);
1601
1602 out:
1603         /* Abort loop in case of pending signal. */
1604         if (signal_pending(current))
1605                 return -EINTR;
1606
1607         return 0;
1608 }
1609
1610 /**
1611  * ccw_purge_blacklisted - purge unused, blacklisted devices
1612  *
1613  * Unregister all ccw devices that are offline and on the blacklist.
1614  */
1615 int ccw_purge_blacklisted(void)
1616 {
1617         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1618         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1619         return 0;
1620 }
1621
1622 static void device_set_disconnected(struct ccw_device *cdev)
1623 {
1624         if (!cdev)
1625                 return;
1626         ccw_device_set_timeout(cdev, 0);
1627         cdev->private->flags.fake_irb = 0;
1628         cdev->private->state = DEV_STATE_DISCONNECTED;
1629         if (cdev->online)
1630                 ccw_device_schedule_recovery();
1631 }
1632
1633 void ccw_device_set_notoper(struct ccw_device *cdev)
1634 {
1635         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1636
1637         CIO_TRACE_EVENT(2, "notoper");
1638         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1639         ccw_device_set_timeout(cdev, 0);
1640         cio_disable_subchannel(sch);
1641         cdev->private->state = DEV_STATE_NOT_OPER;
1642 }
1643
1644 static int io_subchannel_sch_event(struct subchannel *sch, int slow)
1645 {
1646         int event, ret, disc;
1647         unsigned long flags;
1648         enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE, DISC } action;
1649         struct ccw_device *cdev;
1650
1651         spin_lock_irqsave(sch->lock, flags);
1652         cdev = sch_get_cdev(sch);
1653         disc = device_is_disconnected(cdev);
1654         if (disc && slow) {
1655                 /* Disconnected devices are evaluated directly only.*/
1656                 spin_unlock_irqrestore(sch->lock, flags);
1657                 return 0;
1658         }
1659         /* No interrupt after machine check - kill pending timers. */
1660         if (cdev)
1661                 ccw_device_set_timeout(cdev, 0);
1662         if (!disc && !slow) {
1663                 /* Non-disconnected devices are evaluated on the slow path. */
1664                 spin_unlock_irqrestore(sch->lock, flags);
1665                 return -EAGAIN;
1666         }
1667         event = io_subchannel_get_status(sch);
1668         CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
1669                       sch->schid.ssid, sch->schid.sch_no, event,
1670                       disc ? "disconnected" : "normal",
1671                       slow ? "slow" : "fast");
1672         /* Analyze subchannel status. */
1673         action = NONE;
1674         switch (event) {
1675         case CIO_NO_PATH:
1676                 if (disc) {
1677                         /* Check if paths have become available. */
1678                         action = REPROBE;
1679                         break;
1680                 }
1681                 /* fall through */
1682         case CIO_GONE:
1683                 /* Ask driver what to do with device. */
1684                 if (io_subchannel_notify(sch, event))
1685                         action = DISC;
1686                 else
1687                         action = UNREGISTER;
1688                 break;
1689         case CIO_REVALIDATE:
1690                 /* Device will be removed, so no notify necessary. */
1691                 if (disc)
1692                         /* Reprobe because immediate unregister might block. */
1693                         action = REPROBE;
1694                 else
1695                         action = UNREGISTER_PROBE;
1696                 break;
1697         case CIO_OPER:
1698                 if (disc)
1699                         /* Get device operational again. */
1700                         action = REPROBE;
1701                 break;
1702         }
1703         /* Perform action. */
1704         ret = 0;
1705         switch (action) {
1706         case UNREGISTER:
1707         case UNREGISTER_PROBE:
1708                 ccw_device_set_notoper(cdev);
1709                 /* Unregister device (will use subchannel lock). */
1710                 spin_unlock_irqrestore(sch->lock, flags);
1711                 css_sch_device_unregister(sch);
1712                 spin_lock_irqsave(sch->lock, flags);
1713                 break;
1714         case REPROBE:
1715                 ccw_device_trigger_reprobe(cdev);
1716                 break;
1717         case DISC:
1718                 device_set_disconnected(cdev);
1719                 break;
1720         default:
1721                 break;
1722         }
1723         spin_unlock_irqrestore(sch->lock, flags);
1724         /* Probe if necessary. */
1725         if (action == UNREGISTER_PROBE)
1726                 ret = css_probe_device(sch->schid);
1727
1728         return ret;
1729 }
1730
1731 #ifdef CONFIG_CCW_CONSOLE
1732 static struct ccw_device console_cdev;
1733 static char console_cdev_name[10] = "0.x.xxxx";
1734 static struct ccw_device_private console_private;
1735 static int console_cdev_in_use;
1736
1737 static DEFINE_SPINLOCK(ccw_console_lock);
1738
1739 spinlock_t * cio_get_console_lock(void)
1740 {
1741         return &ccw_console_lock;
1742 }
1743
1744 static int ccw_device_console_enable(struct ccw_device *cdev,
1745                                      struct subchannel *sch)
1746 {
1747         int rc;
1748
1749         /* Attach subchannel private data. */
1750         sch->private = cio_get_console_priv();
1751         memset(sch->private, 0, sizeof(struct io_subchannel_private));
1752         io_subchannel_init_fields(sch);
1753         rc = cio_commit_config(sch);
1754         if (rc)
1755                 return rc;
1756         sch->driver = &io_subchannel_driver;
1757         /* Initialize the ccw_device structure. */
1758         cdev->dev.parent= &sch->dev;
1759         rc = io_subchannel_recog(cdev, sch);
1760         if (rc)
1761                 return rc;
1762
1763         /* Now wait for the async. recognition to come to an end. */
1764         spin_lock_irq(cdev->ccwlock);
1765         while (!dev_fsm_final_state(cdev))
1766                 wait_cons_dev();
1767         rc = -EIO;
1768         if (cdev->private->state != DEV_STATE_OFFLINE)
1769                 goto out_unlock;
1770         ccw_device_online(cdev);
1771         while (!dev_fsm_final_state(cdev))
1772                 wait_cons_dev();
1773         if (cdev->private->state != DEV_STATE_ONLINE)
1774                 goto out_unlock;
1775         rc = 0;
1776 out_unlock:
1777         spin_unlock_irq(cdev->ccwlock);
1778         return 0;
1779 }
1780
1781 struct ccw_device *
1782 ccw_device_probe_console(void)
1783 {
1784         struct subchannel *sch;
1785         int ret;
1786
1787         if (xchg(&console_cdev_in_use, 1) != 0)
1788                 return ERR_PTR(-EBUSY);
1789         sch = cio_probe_console();
1790         if (IS_ERR(sch)) {
1791                 console_cdev_in_use = 0;
1792                 return (void *) sch;
1793         }
1794         memset(&console_cdev, 0, sizeof(struct ccw_device));
1795         memset(&console_private, 0, sizeof(struct ccw_device_private));
1796         console_cdev.private = &console_private;
1797         console_private.cdev = &console_cdev;
1798         ret = ccw_device_console_enable(&console_cdev, sch);
1799         if (ret) {
1800                 cio_release_console();
1801                 console_cdev_in_use = 0;
1802                 return ERR_PTR(ret);
1803         }
1804         console_cdev.online = 1;
1805         return &console_cdev;
1806 }
1807
1808 static int ccw_device_pm_restore(struct device *dev);
1809
1810 int ccw_device_force_console(void)
1811 {
1812         if (!console_cdev_in_use)
1813                 return -ENODEV;
1814         return ccw_device_pm_restore(&console_cdev.dev);
1815 }
1816 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1817
1818 const char *cio_get_console_cdev_name(struct subchannel *sch)
1819 {
1820         snprintf(console_cdev_name, 10, "0.%x.%04x",
1821                  sch->schid.ssid, sch->schib.pmcw.dev);
1822         return (const char *)console_cdev_name;
1823 }
1824 #endif
1825
1826 /*
1827  * get ccw_device matching the busid, but only if owned by cdrv
1828  */
1829 static int
1830 __ccwdev_check_busid(struct device *dev, void *id)
1831 {
1832         char *bus_id;
1833
1834         bus_id = id;
1835
1836         return (strcmp(bus_id, dev_name(dev)) == 0);
1837 }
1838
1839
1840 /**
1841  * get_ccwdev_by_busid() - obtain device from a bus id
1842  * @cdrv: driver the device is owned by
1843  * @bus_id: bus id of the device to be searched
1844  *
1845  * This function searches all devices owned by @cdrv for a device with a bus
1846  * id matching @bus_id.
1847  * Returns:
1848  *  If a match is found, its reference count of the found device is increased
1849  *  and it is returned; else %NULL is returned.
1850  */
1851 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1852                                        const char *bus_id)
1853 {
1854         struct device *dev;
1855         struct device_driver *drv;
1856
1857         drv = get_driver(&cdrv->driver);
1858         if (!drv)
1859                 return NULL;
1860
1861         dev = driver_find_device(drv, NULL, (void *)bus_id,
1862                                  __ccwdev_check_busid);
1863         put_driver(drv);
1864
1865         return dev ? to_ccwdev(dev) : NULL;
1866 }
1867
1868 /************************** device driver handling ************************/
1869
1870 /* This is the implementation of the ccw_driver class. The probe, remove
1871  * and release methods are initially very similar to the device_driver
1872  * implementations, with the difference that they have ccw_device
1873  * arguments.
1874  *
1875  * A ccw driver also contains the information that is needed for
1876  * device matching.
1877  */
1878 static int
1879 ccw_device_probe (struct device *dev)
1880 {
1881         struct ccw_device *cdev = to_ccwdev(dev);
1882         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1883         int ret;
1884
1885         cdev->drv = cdrv; /* to let the driver call _set_online */
1886
1887         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1888
1889         if (ret) {
1890                 cdev->drv = NULL;
1891                 return ret;
1892         }
1893
1894         return 0;
1895 }
1896
1897 static int
1898 ccw_device_remove (struct device *dev)
1899 {
1900         struct ccw_device *cdev = to_ccwdev(dev);
1901         struct ccw_driver *cdrv = cdev->drv;
1902         int ret;
1903
1904         if (cdrv->remove)
1905                 cdrv->remove(cdev);
1906         if (cdev->online) {
1907                 cdev->online = 0;
1908                 spin_lock_irq(cdev->ccwlock);
1909                 ret = ccw_device_offline(cdev);
1910                 spin_unlock_irq(cdev->ccwlock);
1911                 if (ret == 0)
1912                         wait_event(cdev->private->wait_q,
1913                                    dev_fsm_final_state(cdev));
1914                 else
1915                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1916                                       "device 0.%x.%04x\n",
1917                                       ret, cdev->private->dev_id.ssid,
1918                                       cdev->private->dev_id.devno);
1919                 /* Give up reference obtained in ccw_device_set_online(). */
1920                 put_device(&cdev->dev);
1921         }
1922         ccw_device_set_timeout(cdev, 0);
1923         cdev->drv = NULL;
1924         return 0;
1925 }
1926
1927 static void ccw_device_shutdown(struct device *dev)
1928 {
1929         struct ccw_device *cdev;
1930
1931         cdev = to_ccwdev(dev);
1932         if (cdev->drv && cdev->drv->shutdown)
1933                 cdev->drv->shutdown(cdev);
1934         disable_cmf(cdev);
1935 }
1936
1937 static int ccw_device_pm_prepare(struct device *dev)
1938 {
1939         struct ccw_device *cdev = to_ccwdev(dev);
1940
1941         if (work_pending(&cdev->private->kick_work))
1942                 return -EAGAIN;
1943         /* Fail while device is being set online/offline. */
1944         if (atomic_read(&cdev->private->onoff))
1945                 return -EAGAIN;
1946
1947         if (cdev->online && cdev->drv && cdev->drv->prepare)
1948                 return cdev->drv->prepare(cdev);
1949
1950         return 0;
1951 }
1952
1953 static void ccw_device_pm_complete(struct device *dev)
1954 {
1955         struct ccw_device *cdev = to_ccwdev(dev);
1956
1957         if (cdev->online && cdev->drv && cdev->drv->complete)
1958                 cdev->drv->complete(cdev);
1959 }
1960
1961 static int ccw_device_pm_freeze(struct device *dev)
1962 {
1963         struct ccw_device *cdev = to_ccwdev(dev);
1964         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1965         int ret, cm_enabled;
1966
1967         /* Fail suspend while device is in transistional state. */
1968         if (!dev_fsm_final_state(cdev))
1969                 return -EAGAIN;
1970         if (!cdev->online)
1971                 return 0;
1972         if (cdev->drv && cdev->drv->freeze) {
1973                 ret = cdev->drv->freeze(cdev);
1974                 if (ret)
1975                         return ret;
1976         }
1977
1978         spin_lock_irq(sch->lock);
1979         cm_enabled = cdev->private->cmb != NULL;
1980         spin_unlock_irq(sch->lock);
1981         if (cm_enabled) {
1982                 /* Don't have the css write on memory. */
1983                 ret = ccw_set_cmf(cdev, 0);
1984                 if (ret)
1985                         return ret;
1986         }
1987         /* From here on, disallow device driver I/O. */
1988         spin_lock_irq(sch->lock);
1989         ret = cio_disable_subchannel(sch);
1990         spin_unlock_irq(sch->lock);
1991
1992         return ret;
1993 }
1994
1995 static int ccw_device_pm_thaw(struct device *dev)
1996 {
1997         struct ccw_device *cdev = to_ccwdev(dev);
1998         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1999         int ret, cm_enabled;
2000
2001         if (!cdev->online)
2002                 return 0;
2003
2004         spin_lock_irq(sch->lock);
2005         /* Allow device driver I/O again. */
2006         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
2007         cm_enabled = cdev->private->cmb != NULL;
2008         spin_unlock_irq(sch->lock);
2009         if (ret)
2010                 return ret;
2011
2012         if (cm_enabled) {
2013                 ret = ccw_set_cmf(cdev, 1);
2014                 if (ret)
2015                         return ret;
2016         }
2017
2018         if (cdev->drv && cdev->drv->thaw)
2019                 ret = cdev->drv->thaw(cdev);
2020
2021         return ret;
2022 }
2023
2024 static void __ccw_device_pm_restore(struct ccw_device *cdev)
2025 {
2026         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2027         int ret;
2028
2029         if (cio_is_console(sch->schid))
2030                 goto out;
2031         /*
2032          * While we were sleeping, devices may have gone or become
2033          * available again. Kick re-detection.
2034          */
2035         spin_lock_irq(sch->lock);
2036         cdev->private->flags.resuming = 1;
2037         ret = ccw_device_recognition(cdev);
2038         spin_unlock_irq(sch->lock);
2039         if (ret) {
2040                 CIO_MSG_EVENT(0, "Couldn't start recognition for device "
2041                               "0.%x.%04x (ret=%d)\n",
2042                               cdev->private->dev_id.ssid,
2043                               cdev->private->dev_id.devno, ret);
2044                 spin_lock_irq(sch->lock);
2045                 cdev->private->state = DEV_STATE_DISCONNECTED;
2046                 spin_unlock_irq(sch->lock);
2047                 /* notify driver after the resume cb */
2048                 goto out;
2049         }
2050         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
2051                    cdev->private->state == DEV_STATE_DISCONNECTED);
2052
2053 out:
2054         cdev->private->flags.resuming = 0;
2055 }
2056
2057 static int resume_handle_boxed(struct ccw_device *cdev)
2058 {
2059         cdev->private->state = DEV_STATE_BOXED;
2060         if (ccw_device_notify(cdev, CIO_BOXED))
2061                 return 0;
2062         ccw_device_schedule_sch_unregister(cdev);
2063         return -ENODEV;
2064 }
2065
2066 static int resume_handle_disc(struct ccw_device *cdev)
2067 {
2068         cdev->private->state = DEV_STATE_DISCONNECTED;
2069         if (ccw_device_notify(cdev, CIO_GONE))
2070                 return 0;
2071         ccw_device_schedule_sch_unregister(cdev);
2072         return -ENODEV;
2073 }
2074
2075 static int ccw_device_pm_restore(struct device *dev)
2076 {
2077         struct ccw_device *cdev = to_ccwdev(dev);
2078         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2079         int ret = 0, cm_enabled;
2080
2081         __ccw_device_pm_restore(cdev);
2082         spin_lock_irq(sch->lock);
2083         if (cio_is_console(sch->schid)) {
2084                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
2085                 spin_unlock_irq(sch->lock);
2086                 goto out_restore;
2087         }
2088         cdev->private->flags.donotify = 0;
2089         /* check recognition results */
2090         switch (cdev->private->state) {
2091         case DEV_STATE_OFFLINE:
2092                 break;
2093         case DEV_STATE_BOXED:
2094                 ret = resume_handle_boxed(cdev);
2095                 spin_unlock_irq(sch->lock);
2096                 if (ret)
2097                         goto out;
2098                 goto out_restore;
2099         case DEV_STATE_DISCONNECTED:
2100                 goto out_disc_unlock;
2101         default:
2102                 goto out_unreg_unlock;
2103         }
2104         /* check if the device id has changed */
2105         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
2106                 CIO_MSG_EVENT(0, "resume: sch 0.%x.%04x: failed (devno "
2107                               "changed from %04x to %04x)\n",
2108                               sch->schid.ssid, sch->schid.sch_no,
2109                               cdev->private->dev_id.devno,
2110                               sch->schib.pmcw.dev);
2111                 goto out_unreg_unlock;
2112         }
2113         /* check if the device type has changed */
2114         if (!ccw_device_test_sense_data(cdev)) {
2115                 ccw_device_update_sense_data(cdev);
2116                 PREPARE_WORK(&cdev->private->kick_work,
2117                              ccw_device_do_unbind_bind);
2118                 queue_work(ccw_device_work, &cdev->private->kick_work);
2119                 ret = -ENODEV;
2120                 goto out_unlock;
2121         }
2122         if (!cdev->online) {
2123                 ret = 0;
2124                 goto out_unlock;
2125         }
2126         ret = ccw_device_online(cdev);
2127         if (ret)
2128                 goto out_disc_unlock;
2129
2130         cm_enabled = cdev->private->cmb != NULL;
2131         spin_unlock_irq(sch->lock);
2132
2133         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
2134         if (cdev->private->state != DEV_STATE_ONLINE) {
2135                 spin_lock_irq(sch->lock);
2136                 goto out_disc_unlock;
2137         }
2138         if (cm_enabled) {
2139                 ret = ccw_set_cmf(cdev, 1);
2140                 if (ret) {
2141                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2142                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
2143                                       cdev->private->dev_id.devno, ret);
2144                         ret = 0;
2145                 }
2146         }
2147
2148 out_restore:
2149         if (cdev->online && cdev->drv && cdev->drv->restore)
2150                 ret = cdev->drv->restore(cdev);
2151 out:
2152         return ret;
2153
2154 out_disc_unlock:
2155         ret = resume_handle_disc(cdev);
2156         spin_unlock_irq(sch->lock);
2157         if (ret)
2158                 return ret;
2159         goto out_restore;
2160
2161 out_unreg_unlock:
2162         ccw_device_schedule_sch_unregister(cdev);
2163         ret = -ENODEV;
2164 out_unlock:
2165         spin_unlock_irq(sch->lock);
2166         return ret;
2167 }
2168
2169 static struct dev_pm_ops ccw_pm_ops = {
2170         .prepare = ccw_device_pm_prepare,
2171         .complete = ccw_device_pm_complete,
2172         .freeze = ccw_device_pm_freeze,
2173         .thaw = ccw_device_pm_thaw,
2174         .restore = ccw_device_pm_restore,
2175 };
2176
2177 struct bus_type ccw_bus_type = {
2178         .name   = "ccw",
2179         .match  = ccw_bus_match,
2180         .uevent = ccw_uevent,
2181         .probe  = ccw_device_probe,
2182         .remove = ccw_device_remove,
2183         .shutdown = ccw_device_shutdown,
2184         .pm = &ccw_pm_ops,
2185 };
2186
2187 /**
2188  * ccw_driver_register() - register a ccw driver
2189  * @cdriver: driver to be registered
2190  *
2191  * This function is mainly a wrapper around driver_register().
2192  * Returns:
2193  *   %0 on success and a negative error value on failure.
2194  */
2195 int ccw_driver_register(struct ccw_driver *cdriver)
2196 {
2197         struct device_driver *drv = &cdriver->driver;
2198
2199         drv->bus = &ccw_bus_type;
2200         drv->name = cdriver->name;
2201         drv->owner = cdriver->owner;
2202
2203         return driver_register(drv);
2204 }
2205
2206 /**
2207  * ccw_driver_unregister() - deregister a ccw driver
2208  * @cdriver: driver to be deregistered
2209  *
2210  * This function is mainly a wrapper around driver_unregister().
2211  */
2212 void ccw_driver_unregister(struct ccw_driver *cdriver)
2213 {
2214         driver_unregister(&cdriver->driver);
2215 }
2216
2217 /* Helper func for qdio. */
2218 struct subchannel_id
2219 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2220 {
2221         struct subchannel *sch;
2222
2223         sch = to_subchannel(cdev->dev.parent);
2224         return sch->schid;
2225 }
2226
2227 MODULE_LICENSE("GPL");
2228 EXPORT_SYMBOL(ccw_device_set_online);
2229 EXPORT_SYMBOL(ccw_device_set_offline);
2230 EXPORT_SYMBOL(ccw_driver_register);
2231 EXPORT_SYMBOL(ccw_driver_unregister);
2232 EXPORT_SYMBOL(get_ccwdev_by_busid);
2233 EXPORT_SYMBOL(ccw_bus_type);
2234 EXPORT_SYMBOL(ccw_device_work);
2235 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);