drivers/s390/cio/device.c

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