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 #include <linux/kernel_stat.h>
  25
  26 #include <asm/ccwdev.h>
  27 #include <asm/cio.h>
  28 #include <asm/param.h>          /* HZ */
  29 #include <asm/cmb.h>
  30 #include <asm/isc.h>
  31
  32 #include "chp.h"
  33 #include "cio.h"
  34 #include "cio_debug.h"
  35 #include "css.h"
  36 #include "device.h"
  37 #include "ioasm.h"
  38 #include "io_sch.h"
  39 #include "blacklist.h"
  40 #include "chsc.h"
  41
  42 static struct timer_list recovery_timer;
  43 static DEFINE_SPINLOCK(recovery_lock);
  44 static int recovery_phase;
  45 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  46
  47 /******************* bus type handling ***********************/
  48
  49 /* The Linux driver model distinguishes between a bus type and
  50  * the bus itself. Of course we only have one channel
  51  * subsystem driver and one channel system per machine, but
  52  * we still use the abstraction. T.R. says it's a good idea. */
  53 static int
  54 ccw_bus_match (struct device * dev, struct device_driver * drv)
  55 {
  56         struct ccw_device *cdev = to_ccwdev(dev);
  57         struct ccw_driver *cdrv = to_ccwdrv(drv);
  58         const struct ccw_device_id *ids = cdrv->ids, *found;
  59
  60         if (!ids)
  61                 return 0;
  62
  63         found = ccw_device_id_match(ids, &cdev->id);
  64         if (!found)
  65                 return 0;
  66
  67         cdev->id.driver_info = found->driver_info;
  68
  69         return 1;
  70 }
  71
  72 /* Store modalias string delimited by prefix/suffix string into buffer with
  73  * specified size. Return length of resulting string (excluding trailing '\0')
  74  * even if string doesn't fit buffer (snprintf semantics). */
  75 static int snprint_alias(char *buf, size_t size,
  76                          struct ccw_device_id *id, const char *suffix)
  77 {
  78         int len;
  79
  80         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  81         if (len > size)
  82                 return len;
  83         buf += len;
  84         size -= len;
  85
  86         if (id->dev_type != 0)
  87                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  88                                 id->dev_model, suffix);
  89         else
  90                 len += snprintf(buf, size, "dtdm%s", suffix);
  91
  92         return len;
  93 }
  94
  95 /* Set up environment variables for ccw device uevent. Return 0 on success,
  96  * non-zero otherwise. */
  97 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  98 {
  99         struct ccw_device *cdev = to_ccwdev(dev);
 100         struct ccw_device_id *id = &(cdev->id);
 101         int ret;
 102         char modalias_buf[30];
 103
 104         /* CU_TYPE= */
 105         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 106         if (ret)
 107                 return ret;
 108
 109         /* CU_MODEL= */
 110         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 111         if (ret)
 112                 return ret;
 113
 114         /* The next two can be zero, that's ok for us */
 115         /* DEV_TYPE= */
 116         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 117         if (ret)
 118                 return ret;
 119
 120         /* DEV_MODEL= */
 121         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 122         if (ret)
 123                 return ret;
 124
 125         /* MODALIAS=  */
 126         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 127         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 128         return ret;
 129 }
 130
 131 static struct bus_type ccw_bus_type;
 132
 133 static void io_subchannel_irq(struct subchannel *);
 134 static int io_subchannel_probe(struct subchannel *);
 135 static int io_subchannel_remove(struct subchannel *);
 136 static void io_subchannel_shutdown(struct subchannel *);
 137 static int io_subchannel_sch_event(struct subchannel *, int);
 138 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 139                                    int);
 140 static void recovery_func(unsigned long data);
 141 wait_queue_head_t ccw_device_init_wq;
 142 atomic_t ccw_device_init_count;
 143
 144 static struct css_device_id io_subchannel_ids[] = {
 145         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 146         { /* end of list */ },
 147 };
 148 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 149
 150 static int io_subchannel_prepare(struct subchannel *sch)
 151 {
 152         struct ccw_device *cdev;
 153         /*
 154          * Don't allow suspend while a ccw device registration
 155          * is still outstanding.
 156          */
 157         cdev = sch_get_cdev(sch);
 158         if (cdev && !device_is_registered(&cdev->dev))
 159                 return -EAGAIN;
 160         return 0;
 161 }
 162
 163 static int io_subchannel_settle(void)
 164 {
 165         int ret;
 166
 167         ret = wait_event_interruptible(ccw_device_init_wq,
 168                                 atomic_read(&ccw_device_init_count) == 0);
 169         if (ret)
 170                 return -EINTR;
 171         flush_workqueue(cio_work_q);
 172         return 0;
 173 }
 174
 175 static struct css_driver io_subchannel_driver = {
 176         .drv = {
 177                 .owner = THIS_MODULE,
 178                 .name = "io_subchannel",
 179         },
 180         .subchannel_type = io_subchannel_ids,
 181         .irq = io_subchannel_irq,
 182         .sch_event = io_subchannel_sch_event,
 183         .chp_event = io_subchannel_chp_event,
 184         .probe = io_subchannel_probe,
 185         .remove = io_subchannel_remove,
 186         .shutdown = io_subchannel_shutdown,
 187         .prepare = io_subchannel_prepare,
 188         .settle = io_subchannel_settle,
 189 };
 190
 191 int __init io_subchannel_init(void)
 192 {
 193         int ret;
 194
 195         init_waitqueue_head(&ccw_device_init_wq);
 196         atomic_set(&ccw_device_init_count, 0);
 197         setup_timer(&recovery_timer, recovery_func, 0);
 198
 199         ret = bus_register(&ccw_bus_type);
 200         if (ret)
 201                 return ret;
 202         ret = css_driver_register(&io_subchannel_driver);
 203         if (ret)
 204                 bus_unregister(&ccw_bus_type);
 205
 206         return ret;
 207 }
 208
 209
 210 /************************ device handling **************************/
 211
 212 /*
 213  * A ccw_device has some interfaces in sysfs in addition to the
 214  * standard ones.
 215  * The following entries are designed to export the information which
 216  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 217  * are obvious, so they don't have an entry :)
 218  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 219  */
 220 static ssize_t
 221 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 222 {
 223         struct subchannel *sch = to_subchannel(dev);
 224         struct chsc_ssd_info *ssd = &sch->ssd_info;
 225         ssize_t ret = 0;
 226         int chp;
 227         int mask;
 228
 229         for (chp = 0; chp < 8; chp++) {
 230                 mask = 0x80 >> chp;
 231                 if (ssd->path_mask & mask)
 232                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 233                 else
 234                         ret += sprintf(buf + ret, "00 ");
 235         }
 236         ret += sprintf (buf+ret, "\n");
 237         return min((ssize_t)PAGE_SIZE, ret);
 238 }
 239
 240 static ssize_t
 241 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 242 {
 243         struct subchannel *sch = to_subchannel(dev);
 244         struct pmcw *pmcw = &sch->schib.pmcw;
 245
 246         return sprintf (buf, "%02x %02x %02x\n",
 247                         pmcw->pim, pmcw->pam, pmcw->pom);
 248 }
 249
 250 static ssize_t
 251 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 252 {
 253         struct ccw_device *cdev = to_ccwdev(dev);
 254         struct ccw_device_id *id = &(cdev->id);
 255
 256         if (id->dev_type != 0)
 257                 return sprintf(buf, "%04x/%02x\n",
 258                                 id->dev_type, id->dev_model);
 259         else
 260                 return sprintf(buf, "n/a\n");
 261 }
 262
 263 static ssize_t
 264 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 265 {
 266         struct ccw_device *cdev = to_ccwdev(dev);
 267         struct ccw_device_id *id = &(cdev->id);
 268
 269         return sprintf(buf, "%04x/%02x\n",
 270                        id->cu_type, id->cu_model);
 271 }
 272
 273 static ssize_t
 274 modalias_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         int len;
 279
 280         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 281
 282         return len > PAGE_SIZE ? PAGE_SIZE : len;
 283 }
 284
 285 static ssize_t
 286 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 287 {
 288         struct ccw_device *cdev = to_ccwdev(dev);
 289
 290         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 291 }
 292
 293 int ccw_device_is_orphan(struct ccw_device *cdev)
 294 {
 295         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 296 }
 297
 298 static void ccw_device_unregister(struct ccw_device *cdev)
 299 {
 300         if (device_is_registered(&cdev->dev)) {
 301                 /* Undo device_add(). */
 302                 device_del(&cdev->dev);
 303         }
 304         if (cdev->private->flags.initialized) {
 305                 cdev->private->flags.initialized = 0;
 306                 /* Release reference from device_initialize(). */
 307                 put_device(&cdev->dev);
 308         }
 309 }
 310
 311 static void io_subchannel_quiesce(struct subchannel *);
 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         struct subchannel *sch;
 327         int ret, state;
 328
 329         if (!cdev)
 330                 return -ENODEV;
 331         if (!cdev->online || !cdev->drv)
 332                 return -EINVAL;
 333
 334         if (cdev->drv->set_offline) {
 335                 ret = cdev->drv->set_offline(cdev);
 336                 if (ret != 0)
 337                         return ret;
 338         }
 339         cdev->online = 0;
 340         spin_lock_irq(cdev->ccwlock);
 341         sch = to_subchannel(cdev->dev.parent);
 342         /* Wait until a final state or DISCONNECTED is reached */
 343         while (!dev_fsm_final_state(cdev) &&
 344                cdev->private->state != DEV_STATE_DISCONNECTED) {
 345                 spin_unlock_irq(cdev->ccwlock);
 346                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 347                            cdev->private->state == DEV_STATE_DISCONNECTED));
 348                 spin_lock_irq(cdev->ccwlock);
 349         }
 350         do {
 351                 ret = ccw_device_offline(cdev);
 352                 if (!ret)
 353                         break;
 354                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 355                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 356                               cdev->private->dev_id.devno);
 357                 if (ret != -EBUSY)
 358                         goto error;
 359                 state = cdev->private->state;
 360                 spin_unlock_irq(cdev->ccwlock);
 361                 io_subchannel_quiesce(sch);
 362                 spin_lock_irq(cdev->ccwlock);
 363                 cdev->private->state = state;
 364         } while (ret == -EBUSY);
 365         spin_unlock_irq(cdev->ccwlock);
 366         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 367                    cdev->private->state == DEV_STATE_DISCONNECTED));
 368         /* Inform the user if set offline failed. */
 369         if (cdev->private->state == DEV_STATE_BOXED) {
 370                 pr_warning("%s: The device entered boxed state while "
 371                            "being set offline\n", dev_name(&cdev->dev));
 372         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 373                 pr_warning("%s: The device stopped operating while "
 374                            "being set offline\n", dev_name(&cdev->dev));
 375         }
 376         /* Give up reference from ccw_device_set_online(). */
 377         put_device(&cdev->dev);
 378         return 0;
 379
 380 error:
 381         cdev->private->state = DEV_STATE_OFFLINE;
 382         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 383         spin_unlock_irq(cdev->ccwlock);
 384         /* Give up reference from ccw_device_set_online(). */
 385         put_device(&cdev->dev);
 386         return -ENODEV;
 387 }
 388
 389 /**
 390  * ccw_device_set_online() - enable a ccw device for I/O
 391  * @cdev: target ccw device
 392  *
 393  * This function first enables @cdev and then calls the driver's set_online()
 394  * function for @cdev, if given. If set_online() returns an error, @cdev is
 395  * disabled again.
 396  * Returns:
 397  *   %0 on success and a negative error value on failure.
 398  * Context:
 399  *  enabled, ccw device lock not held
 400  */
 401 int ccw_device_set_online(struct ccw_device *cdev)
 402 {
 403         int ret;
 404         int ret2;
 405
 406         if (!cdev)
 407                 return -ENODEV;
 408         if (cdev->online || !cdev->drv)
 409                 return -EINVAL;
 410         /* Hold on to an extra reference while device is online. */
 411         if (!get_device(&cdev->dev))
 412                 return -ENODEV;
 413
 414         spin_lock_irq(cdev->ccwlock);
 415         ret = ccw_device_online(cdev);
 416         spin_unlock_irq(cdev->ccwlock);
 417         if (ret == 0)
 418                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 419         else {
 420                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 421                               "device 0.%x.%04x\n",
 422                               ret, cdev->private->dev_id.ssid,
 423                               cdev->private->dev_id.devno);
 424                 /* Give up online reference since onlining failed. */
 425                 put_device(&cdev->dev);
 426                 return ret;
 427         }
 428         spin_lock_irq(cdev->ccwlock);
 429         /* Check if online processing was successful */
 430         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 431             (cdev->private->state != DEV_STATE_W4SENSE)) {
 432                 spin_unlock_irq(cdev->ccwlock);
 433                 /* Inform the user that set online failed. */
 434                 if (cdev->private->state == DEV_STATE_BOXED) {
 435                         pr_warning("%s: Setting the device online failed "
 436                                    "because it is boxed\n",
 437                                    dev_name(&cdev->dev));
 438                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 439                         pr_warning("%s: Setting the device online failed "
 440                                    "because it is not operational\n",
 441                                    dev_name(&cdev->dev));
 442                 }
 443                 /* Give up online reference since onlining failed. */
 444                 put_device(&cdev->dev);
 445                 return -ENODEV;
 446         }
 447         spin_unlock_irq(cdev->ccwlock);
 448         if (cdev->drv->set_online)
 449                 ret = cdev->drv->set_online(cdev);
 450         if (ret)
 451                 goto rollback;
 452         cdev->online = 1;
 453         return 0;
 454
 455 rollback:
 456         spin_lock_irq(cdev->ccwlock);
 457         /* Wait until a final state or DISCONNECTED is reached */
 458         while (!dev_fsm_final_state(cdev) &&
 459                cdev->private->state != DEV_STATE_DISCONNECTED) {
 460                 spin_unlock_irq(cdev->ccwlock);
 461                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 462                            cdev->private->state == DEV_STATE_DISCONNECTED));
 463                 spin_lock_irq(cdev->ccwlock);
 464         }
 465         ret2 = ccw_device_offline(cdev);
 466         if (ret2)
 467                 goto error;
 468         spin_unlock_irq(cdev->ccwlock);
 469         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 470                    cdev->private->state == DEV_STATE_DISCONNECTED));
 471         /* Give up online reference since onlining failed. */
 472         put_device(&cdev->dev);
 473         return ret;
 474
 475 error:
 476         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 477                       "device 0.%x.%04x\n",
 478                       ret2, cdev->private->dev_id.ssid,
 479                       cdev->private->dev_id.devno);
 480         cdev->private->state = DEV_STATE_OFFLINE;
 481         spin_unlock_irq(cdev->ccwlock);
 482         /* Give up online reference since onlining failed. */
 483         put_device(&cdev->dev);
 484         return ret;
 485 }
 486
 487 static int online_store_handle_offline(struct ccw_device *cdev)
 488 {
 489         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 490                 spin_lock_irq(cdev->ccwlock);
 491                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 492                 spin_unlock_irq(cdev->ccwlock);
 493                 return 0;
 494         }
 495         if (cdev->drv && cdev->drv->set_offline)
 496                 return ccw_device_set_offline(cdev);
 497         return -EINVAL;
 498 }
 499
 500 static int online_store_recog_and_online(struct ccw_device *cdev)
 501 {
 502         /* Do device recognition, if needed. */
 503         if (cdev->private->state == DEV_STATE_BOXED) {
 504                 spin_lock_irq(cdev->ccwlock);
 505                 ccw_device_recognition(cdev);
 506                 spin_unlock_irq(cdev->ccwlock);
 507                 wait_event(cdev->private->wait_q,
 508                            cdev->private->flags.recog_done);
 509                 if (cdev->private->state != DEV_STATE_OFFLINE)
 510                         /* recognition failed */
 511                         return -EAGAIN;
 512         }
 513         if (cdev->drv && cdev->drv->set_online)
 514                 return ccw_device_set_online(cdev);
 515         return -EINVAL;
 516 }
 517
 518 static int online_store_handle_online(struct ccw_device *cdev, int force)
 519 {
 520         int ret;
 521
 522         ret = online_store_recog_and_online(cdev);
 523         if (ret && !force)
 524                 return ret;
 525         if (force && cdev->private->state == DEV_STATE_BOXED) {
 526                 ret = ccw_device_stlck(cdev);
 527                 if (ret)
 528                         return ret;
 529                 if (cdev->id.cu_type == 0)
 530                         cdev->private->state = DEV_STATE_NOT_OPER;
 531                 ret = online_store_recog_and_online(cdev);
 532                 if (ret)
 533                         return ret;
 534         }
 535         return 0;
 536 }
 537
 538 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 539                              const char *buf, size_t count)
 540 {
 541         struct ccw_device *cdev = to_ccwdev(dev);
 542         int force, ret;
 543         unsigned long i;
 544
 545         /* Prevent conflict between multiple on-/offline processing requests. */
 546         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 547                 return -EAGAIN;
 548         /* Prevent conflict between internal I/Os and on-/offline processing. */
 549         if (!dev_fsm_final_state(cdev) &&
 550             cdev->private->state != DEV_STATE_DISCONNECTED) {
 551                 ret = -EAGAIN;
 552                 goto out_onoff;
 553         }
 554         /* Prevent conflict between pending work and on-/offline processing.*/
 555         if (work_pending(&cdev->private->todo_work)) {
 556                 ret = -EAGAIN;
 557                 goto out_onoff;
 558         }
 559
 560         if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
 561                 ret = -EINVAL;
 562                 goto out_onoff;
 563         }
 564         if (!strncmp(buf, "force\n", count)) {
 565                 force = 1;
 566                 i = 1;
 567                 ret = 0;
 568         } else {
 569                 force = 0;
 570                 ret = strict_strtoul(buf, 16, &i);
 571         }
 572         if (ret)
 573                 goto out;
 574         switch (i) {
 575         case 0:
 576                 ret = online_store_handle_offline(cdev);
 577                 break;
 578         case 1:
 579                 ret = online_store_handle_online(cdev, force);
 580                 break;
 581         default:
 582                 ret = -EINVAL;
 583         }
 584 out:
 585         if (cdev->drv)
 586                 module_put(cdev->drv->driver.owner);
 587 out_onoff:
 588         atomic_set(&cdev->private->onoff, 0);
 589         return (ret < 0) ? ret : count;
 590 }
 591
 592 static ssize_t
 593 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 594 {
 595         struct ccw_device *cdev = to_ccwdev(dev);
 596         struct subchannel *sch;
 597
 598         if (ccw_device_is_orphan(cdev))
 599                 return sprintf(buf, "no device\n");
 600         switch (cdev->private->state) {
 601         case DEV_STATE_BOXED:
 602                 return sprintf(buf, "boxed\n");
 603         case DEV_STATE_DISCONNECTED:
 604         case DEV_STATE_DISCONNECTED_SENSE_ID:
 605         case DEV_STATE_NOT_OPER:
 606                 sch = to_subchannel(dev->parent);
 607                 if (!sch->lpm)
 608                         return sprintf(buf, "no path\n");
 609                 else
 610                         return sprintf(buf, "no device\n");
 611         default:
 612                 /* All other states considered fine. */
 613                 return sprintf(buf, "good\n");
 614         }
 615 }
 616
 617 static ssize_t
 618 initiate_logging(struct device *dev, struct device_attribute *attr,
 619                  const char *buf, size_t count)
 620 {
 621         struct subchannel *sch = to_subchannel(dev);
 622         int rc;
 623
 624         rc = chsc_siosl(sch->schid);
 625         if (rc < 0) {
 626                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
 627                            "errno=%d\n",
 628                            sch->schid.ssid, sch->schid.sch_no, rc);
 629                 return rc;
 630         }
 631         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 632                   sch->schid.ssid, sch->schid.sch_no);
 633         return count;
 634 }
 635
 636 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 637 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 638 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 639 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 640 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 641 static DEVICE_ATTR(online, 0644, online_show, online_store);
 642 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 643 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 644
 645 static struct attribute *io_subchannel_attrs[] = {
 646         &dev_attr_chpids.attr,
 647         &dev_attr_pimpampom.attr,
 648         &dev_attr_logging.attr,
 649         NULL,
 650 };
 651
 652 static struct attribute_group io_subchannel_attr_group = {
 653         .attrs = io_subchannel_attrs,
 654 };
 655
 656 static struct attribute * ccwdev_attrs[] = {
 657         &dev_attr_devtype.attr,
 658         &dev_attr_cutype.attr,
 659         &dev_attr_modalias.attr,
 660         &dev_attr_online.attr,
 661         &dev_attr_cmb_enable.attr,
 662         &dev_attr_availability.attr,
 663         NULL,
 664 };
 665
 666 static struct attribute_group ccwdev_attr_group = {
 667         .attrs = ccwdev_attrs,
 668 };
 669
 670 static const struct attribute_group *ccwdev_attr_groups[] = {
 671         &ccwdev_attr_group,
 672         NULL,
 673 };
 674
 675 /* this is a simple abstraction for device_register that sets the
 676  * correct bus type and adds the bus specific files */
 677 static int ccw_device_register(struct ccw_device *cdev)
 678 {
 679         struct device *dev = &cdev->dev;
 680         int ret;
 681
 682         dev->bus = &ccw_bus_type;
 683         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 684                            cdev->private->dev_id.devno);
 685         if (ret)
 686                 return ret;
 687         return device_add(dev);
 688 }
 689
 690 static int match_dev_id(struct device *dev, void *data)
 691 {
 692         struct ccw_device *cdev = to_ccwdev(dev);
 693         struct ccw_dev_id *dev_id = data;
 694
 695         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 696 }
 697
 698 /**
 699  * get_ccwdev_by_dev_id() - obtain device from a ccw device id
 700  * @dev_id: id of the device to be searched
 701  *
 702  * This function searches all devices attached to the ccw bus for a device
 703  * matching @dev_id.
 704  * Returns:
 705  *  If a device is found its reference count is increased and returned;
 706  *  else %NULL is returned.
 707  */
 708 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 709 {
 710         struct device *dev;
 711
 712         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 713
 714         return dev ? to_ccwdev(dev) : NULL;
 715 }
 716 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
 717
 718 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 719 {
 720         int ret;
 721
 722         if (device_is_registered(&cdev->dev)) {
 723                 device_release_driver(&cdev->dev);
 724                 ret = device_attach(&cdev->dev);
 725                 WARN_ON(ret == -ENODEV);
 726         }
 727 }
 728
 729 static void
 730 ccw_device_release(struct device *dev)
 731 {
 732         struct ccw_device *cdev;
 733
 734         cdev = to_ccwdev(dev);
 735         /* Release reference of parent subchannel. */
 736         put_device(cdev->dev.parent);
 737         kfree(cdev->private);
 738         kfree(cdev);
 739 }
 740
 741 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 742 {
 743         struct ccw_device *cdev;
 744
 745         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 746         if (cdev) {
 747                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 748                                         GFP_KERNEL | GFP_DMA);
 749                 if (cdev->private)
 750                         return cdev;
 751         }
 752         kfree(cdev);
 753         return ERR_PTR(-ENOMEM);
 754 }
 755
 756 static void ccw_device_todo(struct work_struct *work);
 757
 758 static int io_subchannel_initialize_dev(struct subchannel *sch,
 759                                         struct ccw_device *cdev)
 760 {
 761         cdev->private->cdev = cdev;
 762         cdev->private->int_class = IOINT_CIO;
 763         atomic_set(&cdev->private->onoff, 0);
 764         cdev->dev.parent = &sch->dev;
 765         cdev->dev.release = ccw_device_release;
 766         INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
 767         cdev->dev.groups = ccwdev_attr_groups;
 768         /* Do first half of device_register. */
 769         device_initialize(&cdev->dev);
 770         if (!get_device(&sch->dev)) {
 771                 /* Release reference from device_initialize(). */
 772                 put_device(&cdev->dev);
 773                 return -ENODEV;
 774         }
 775         cdev->private->flags.initialized = 1;
 776         return 0;
 777 }
 778
 779 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 780 {
 781         struct ccw_device *cdev;
 782         int ret;
 783
 784         cdev = io_subchannel_allocate_dev(sch);
 785         if (!IS_ERR(cdev)) {
 786                 ret = io_subchannel_initialize_dev(sch, cdev);
 787                 if (ret)
 788                         cdev = ERR_PTR(ret);
 789         }
 790         return cdev;
 791 }
 792
 793 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 794
 795 static void sch_create_and_recog_new_device(struct subchannel *sch)
 796 {
 797         struct ccw_device *cdev;
 798
 799         /* Need to allocate a new ccw device. */
 800         cdev = io_subchannel_create_ccwdev(sch);
 801         if (IS_ERR(cdev)) {
 802                 /* OK, we did everything we could... */
 803                 css_sch_device_unregister(sch);
 804                 return;
 805         }
 806         /* Start recognition for the new ccw device. */
 807         io_subchannel_recog(cdev, sch);
 808 }
 809
 810 /*
 811  * Register recognized device.
 812  */
 813 static void io_subchannel_register(struct ccw_device *cdev)
 814 {
 815         struct subchannel *sch;
 816         int ret, adjust_init_count = 1;
 817         unsigned long flags;
 818
 819         sch = to_subchannel(cdev->dev.parent);
 820         /*
 821          * Check if subchannel is still registered. It may have become
 822          * unregistered if a machine check hit us after finishing
 823          * device recognition but before the register work could be
 824          * queued.
 825          */
 826         if (!device_is_registered(&sch->dev))
 827                 goto out_err;
 828         css_update_ssd_info(sch);
 829         /*
 830          * io_subchannel_register() will also be called after device
 831          * recognition has been done for a boxed device (which will already
 832          * be registered). We need to reprobe since we may now have sense id
 833          * information.
 834          */
 835         if (device_is_registered(&cdev->dev)) {
 836                 if (!cdev->drv) {
 837                         ret = device_reprobe(&cdev->dev);
 838                         if (ret)
 839                                 /* We can't do much here. */
 840                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 841                                               " %d for 0.%x.%04x\n", ret,
 842                                               cdev->private->dev_id.ssid,
 843                                               cdev->private->dev_id.devno);
 844                 }
 845                 adjust_init_count = 0;
 846                 goto out;
 847         }
 848         /*
 849          * Now we know this subchannel will stay, we can throw
 850          * our delayed uevent.
 851          */
 852         dev_set_uevent_suppress(&sch->dev, 0);
 853         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 854         /* make it known to the system */
 855         ret = ccw_device_register(cdev);
 856         if (ret) {
 857                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 858                               cdev->private->dev_id.ssid,
 859                               cdev->private->dev_id.devno, ret);
 860                 spin_lock_irqsave(sch->lock, flags);
 861                 sch_set_cdev(sch, NULL);
 862                 spin_unlock_irqrestore(sch->lock, flags);
 863                 /* Release initial device reference. */
 864                 put_device(&cdev->dev);
 865                 goto out_err;
 866         }
 867 out:
 868         cdev->private->flags.recog_done = 1;
 869         wake_up(&cdev->private->wait_q);
 870 out_err:
 871         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 872                 wake_up(&ccw_device_init_wq);
 873 }
 874
 875 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 876 {
 877         struct subchannel *sch;
 878
 879         /* Get subchannel reference for local processing. */
 880         if (!get_device(cdev->dev.parent))
 881                 return;
 882         sch = to_subchannel(cdev->dev.parent);
 883         css_sch_device_unregister(sch);
 884         /* Release subchannel reference for local processing. */
 885         put_device(&sch->dev);
 886 }
 887
 888 /*
 889  * subchannel recognition done. Called from the state machine.
 890  */
 891 void
 892 io_subchannel_recog_done(struct ccw_device *cdev)
 893 {
 894         if (css_init_done == 0) {
 895                 cdev->private->flags.recog_done = 1;
 896                 return;
 897         }
 898         switch (cdev->private->state) {
 899         case DEV_STATE_BOXED:
 900                 /* Device did not respond in time. */
 901         case DEV_STATE_NOT_OPER:
 902                 cdev->private->flags.recog_done = 1;
 903                 /* Remove device found not operational. */
 904                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 905                 if (atomic_dec_and_test(&ccw_device_init_count))
 906                         wake_up(&ccw_device_init_wq);
 907                 break;
 908         case DEV_STATE_OFFLINE:
 909                 /*
 910                  * We can't register the device in interrupt context so
 911                  * we schedule a work item.
 912                  */
 913                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 914                 break;
 915         }
 916 }
 917
 918 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 919 {
 920         struct ccw_device_private *priv;
 921
 922         cdev->ccwlock = sch->lock;
 923
 924         /* Init private data. */
 925         priv = cdev->private;
 926         priv->dev_id.devno = sch->schib.pmcw.dev;
 927         priv->dev_id.ssid = sch->schid.ssid;
 928         priv->schid = sch->schid;
 929         priv->state = DEV_STATE_NOT_OPER;
 930         INIT_LIST_HEAD(&priv->cmb_list);
 931         init_waitqueue_head(&priv->wait_q);
 932         init_timer(&priv->timer);
 933
 934         /* Increase counter of devices currently in recognition. */
 935         atomic_inc(&ccw_device_init_count);
 936
 937         /* Start async. device sensing. */
 938         spin_lock_irq(sch->lock);
 939         sch_set_cdev(sch, cdev);
 940         ccw_device_recognition(cdev);
 941         spin_unlock_irq(sch->lock);
 942 }
 943
 944 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 945                                   struct subchannel *sch)
 946 {
 947         struct subchannel *old_sch;
 948         int rc, old_enabled = 0;
 949
 950         old_sch = to_subchannel(cdev->dev.parent);
 951         /* Obtain child reference for new parent. */
 952         if (!get_device(&sch->dev))
 953                 return -ENODEV;
 954
 955         if (!sch_is_pseudo_sch(old_sch)) {
 956                 spin_lock_irq(old_sch->lock);
 957                 old_enabled = old_sch->schib.pmcw.ena;
 958                 rc = 0;
 959                 if (old_enabled)
 960                         rc = cio_disable_subchannel(old_sch);
 961                 spin_unlock_irq(old_sch->lock);
 962                 if (rc == -EBUSY) {
 963                         /* Release child reference for new parent. */
 964                         put_device(&sch->dev);
 965                         return rc;
 966                 }
 967         }
 968
 969         mutex_lock(&sch->reg_mutex);
 970         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 971         mutex_unlock(&sch->reg_mutex);
 972         if (rc) {
 973                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 974                               cdev->private->dev_id.ssid,
 975                               cdev->private->dev_id.devno, sch->schid.ssid,
 976                               sch->schib.pmcw.dev, rc);
 977                 if (old_enabled) {
 978                         /* Try to reenable the old subchannel. */
 979                         spin_lock_irq(old_sch->lock);
 980                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 981                         spin_unlock_irq(old_sch->lock);
 982                 }
 983                 /* Release child reference for new parent. */
 984                 put_device(&sch->dev);
 985                 return rc;
 986         }
 987         /* Clean up old subchannel. */
 988         if (!sch_is_pseudo_sch(old_sch)) {
 989                 spin_lock_irq(old_sch->lock);
 990                 sch_set_cdev(old_sch, NULL);
 991                 spin_unlock_irq(old_sch->lock);
 992                 css_schedule_eval(old_sch->schid);
 993         }
 994         /* Release child reference for old parent. */
 995         put_device(&old_sch->dev);
 996         /* Initialize new subchannel. */
 997         spin_lock_irq(sch->lock);
 998         cdev->private->schid = sch->schid;
 999         cdev->ccwlock = sch->lock;
1000         if (!sch_is_pseudo_sch(sch))
1001                 sch_set_cdev(sch, cdev);
1002         spin_unlock_irq(sch->lock);
1003         if (!sch_is_pseudo_sch(sch))
1004                 css_update_ssd_info(sch);
1005         return 0;
1006 }
1007
1008 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1009 {
1010         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1011         struct channel_subsystem *css = to_css(sch->dev.parent);
1012
1013         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1014 }
1015
1016 static void io_subchannel_irq(struct subchannel *sch)
1017 {
1018         struct ccw_device *cdev;
1019
1020         cdev = sch_get_cdev(sch);
1021
1022         CIO_TRACE_EVENT(6, "IRQ");
1023         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1024         if (cdev)
1025                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1026         else
1027                 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
1028 }
1029
1030 void io_subchannel_init_config(struct subchannel *sch)
1031 {
1032         memset(&sch->config, 0, sizeof(sch->config));
1033         sch->config.csense = 1;
1034 }
1035
1036 static void io_subchannel_init_fields(struct subchannel *sch)
1037 {
1038         if (cio_is_console(sch->schid))
1039                 sch->opm = 0xff;
1040         else
1041                 sch->opm = chp_get_sch_opm(sch);
1042         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1043         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1044
1045         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1046                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1047                       sch->schib.pmcw.dev, sch->schid.ssid,
1048                       sch->schid.sch_no, sch->schib.pmcw.pim,
1049                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1050
1051         io_subchannel_init_config(sch);
1052 }
1053
1054 /*
1055  * Note: We always return 0 so that we bind to the device even on error.
1056  * This is needed so that our remove function is called on unregister.
1057  */
1058 static int io_subchannel_probe(struct subchannel *sch)
1059 {
1060         struct io_subchannel_private *io_priv;
1061         struct ccw_device *cdev;
1062         int rc;
1063
1064         if (cio_is_console(sch->schid)) {
1065                 rc = sysfs_create_group(&sch->dev.kobj,
1066                                         &io_subchannel_attr_group);
1067                 if (rc)
1068                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1069                                       "attributes for subchannel "
1070                                       "0.%x.%04x (rc=%d)\n",
1071                                       sch->schid.ssid, sch->schid.sch_no, rc);
1072                 /*
1073                  * The console subchannel already has an associated ccw_device.
1074                  * Throw the delayed uevent for the subchannel, register
1075                  * the ccw_device and exit.
1076                  */
1077                 dev_set_uevent_suppress(&sch->dev, 0);
1078                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1079                 cdev = sch_get_cdev(sch);
1080                 cdev->dev.groups = ccwdev_attr_groups;
1081                 device_initialize(&cdev->dev);
1082                 cdev->private->flags.initialized = 1;
1083                 ccw_device_register(cdev);
1084                 /*
1085                  * Check if the device is already online. If it is
1086                  * the reference count needs to be corrected since we
1087                  * didn't obtain a reference in ccw_device_set_online.
1088                  */
1089                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1090                     cdev->private->state != DEV_STATE_OFFLINE &&
1091                     cdev->private->state != DEV_STATE_BOXED)
1092                         get_device(&cdev->dev);
1093                 return 0;
1094         }
1095         io_subchannel_init_fields(sch);
1096         rc = cio_commit_config(sch);
1097         if (rc)
1098                 goto out_schedule;
1099         rc = sysfs_create_group(&sch->dev.kobj,
1100                                 &io_subchannel_attr_group);
1101         if (rc)
1102                 goto out_schedule;
1103         /* Allocate I/O subchannel private data. */
1104         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1105         if (!io_priv)
1106                 goto out_schedule;
1107
1108         set_io_private(sch, io_priv);
1109         css_schedule_eval(sch->schid);
1110         return 0;
1111
1112 out_schedule:
1113         spin_lock_irq(sch->lock);
1114         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1115         spin_unlock_irq(sch->lock);
1116         return 0;
1117 }
1118
1119 static int
1120 io_subchannel_remove (struct subchannel *sch)
1121 {
1122         struct io_subchannel_private *io_priv = to_io_private(sch);
1123         struct ccw_device *cdev;
1124
1125         cdev = sch_get_cdev(sch);
1126         if (!cdev)
1127                 goto out_free;
1128         io_subchannel_quiesce(sch);
1129         /* Set ccw device to not operational and drop reference. */
1130         spin_lock_irq(cdev->ccwlock);
1131         sch_set_cdev(sch, NULL);
1132         set_io_private(sch, NULL);
1133         cdev->private->state = DEV_STATE_NOT_OPER;
1134         spin_unlock_irq(cdev->ccwlock);
1135         ccw_device_unregister(cdev);
1136 out_free:
1137         kfree(io_priv);
1138         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1139         return 0;
1140 }
1141
1142 static void io_subchannel_verify(struct subchannel *sch)
1143 {
1144         struct ccw_device *cdev;
1145
1146         cdev = sch_get_cdev(sch);
1147         if (cdev)
1148                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1149 }
1150
1151 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1152 {
1153         struct ccw_device *cdev;
1154
1155         cdev = sch_get_cdev(sch);
1156         if (!cdev)
1157                 return;
1158         if (cio_update_schib(sch))
1159                 goto err;
1160         /* Check for I/O on path. */
1161         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1162                 goto out;
1163         if (cdev->private->state == DEV_STATE_ONLINE) {
1164                 ccw_device_kill_io(cdev);
1165                 goto out;
1166         }
1167         if (cio_clear(sch))
1168                 goto err;
1169 out:
1170         /* Trigger path verification. */
1171         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1172         return;
1173
1174 err:
1175         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1176 }
1177
1178 static int io_subchannel_chp_event(struct subchannel *sch,
1179                                    struct chp_link *link, int event)
1180 {
1181         struct ccw_device *cdev = sch_get_cdev(sch);
1182         int mask;
1183
1184         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1185         if (!mask)
1186                 return 0;
1187         switch (event) {
1188         case CHP_VARY_OFF:
1189                 sch->opm &= ~mask;
1190                 sch->lpm &= ~mask;
1191                 if (cdev)
1192                         cdev->private->path_gone_mask |= mask;
1193                 io_subchannel_terminate_path(sch, mask);
1194                 break;
1195         case CHP_VARY_ON:
1196                 sch->opm |= mask;
1197                 sch->lpm |= mask;
1198                 if (cdev)
1199                         cdev->private->path_new_mask |= mask;
1200                 io_subchannel_verify(sch);
1201                 break;
1202         case CHP_OFFLINE:
1203                 if (cio_update_schib(sch))
1204                         return -ENODEV;
1205                 if (cdev)
1206                         cdev->private->path_gone_mask |= mask;
1207                 io_subchannel_terminate_path(sch, mask);
1208                 break;
1209         case CHP_ONLINE:
1210                 if (cio_update_schib(sch))
1211                         return -ENODEV;
1212                 sch->lpm |= mask & sch->opm;
1213                 if (cdev)
1214                         cdev->private->path_new_mask |= mask;
1215                 io_subchannel_verify(sch);
1216                 break;
1217         }
1218         return 0;
1219 }
1220
1221 static void io_subchannel_quiesce(struct subchannel *sch)
1222 {
1223         struct ccw_device *cdev;
1224         int ret;
1225
1226         spin_lock_irq(sch->lock);
1227         cdev = sch_get_cdev(sch);
1228         if (cio_is_console(sch->schid))
1229                 goto out_unlock;
1230         if (!sch->schib.pmcw.ena)
1231                 goto out_unlock;
1232         ret = cio_disable_subchannel(sch);
1233         if (ret != -EBUSY)
1234                 goto out_unlock;
1235         if (cdev->handler)
1236                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1237         while (ret == -EBUSY) {
1238                 cdev->private->state = DEV_STATE_QUIESCE;
1239                 cdev->private->iretry = 255;
1240                 ret = ccw_device_cancel_halt_clear(cdev);
1241                 if (ret == -EBUSY) {
1242                         ccw_device_set_timeout(cdev, HZ/10);
1243                         spin_unlock_irq(sch->lock);
1244                         wait_event(cdev->private->wait_q,
1245                                    cdev->private->state != DEV_STATE_QUIESCE);
1246                         spin_lock_irq(sch->lock);
1247                 }
1248                 ret = cio_disable_subchannel(sch);
1249         }
1250 out_unlock:
1251         spin_unlock_irq(sch->lock);
1252 }
1253
1254 static void io_subchannel_shutdown(struct subchannel *sch)
1255 {
1256         io_subchannel_quiesce(sch);
1257 }
1258
1259 static int device_is_disconnected(struct ccw_device *cdev)
1260 {
1261         if (!cdev)
1262                 return 0;
1263         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1264                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1265 }
1266
1267 static int recovery_check(struct device *dev, void *data)
1268 {
1269         struct ccw_device *cdev = to_ccwdev(dev);
1270         int *redo = data;
1271
1272         spin_lock_irq(cdev->ccwlock);
1273         switch (cdev->private->state) {
1274         case DEV_STATE_DISCONNECTED:
1275                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1276                               cdev->private->dev_id.ssid,
1277                               cdev->private->dev_id.devno);
1278                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1279                 *redo = 1;
1280                 break;
1281         case DEV_STATE_DISCONNECTED_SENSE_ID:
1282                 *redo = 1;
1283                 break;
1284         }
1285         spin_unlock_irq(cdev->ccwlock);
1286
1287         return 0;
1288 }
1289
1290 static void recovery_work_func(struct work_struct *unused)
1291 {
1292         int redo = 0;
1293
1294         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1295         if (redo) {
1296                 spin_lock_irq(&recovery_lock);
1297                 if (!timer_pending(&recovery_timer)) {
1298                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1299                                 recovery_phase++;
1300                         mod_timer(&recovery_timer, jiffies +
1301                                   recovery_delay[recovery_phase] * HZ);
1302                 }
1303                 spin_unlock_irq(&recovery_lock);
1304         } else
1305                 CIO_MSG_EVENT(4, "recovery: end\n");
1306 }
1307
1308 static DECLARE_WORK(recovery_work, recovery_work_func);
1309
1310 static void recovery_func(unsigned long data)
1311 {
1312         /*
1313          * We can't do our recovery in softirq context and it's not
1314          * performance critical, so we schedule it.
1315          */
1316         schedule_work(&recovery_work);
1317 }
1318
1319 static void ccw_device_schedule_recovery(void)
1320 {
1321         unsigned long flags;
1322
1323         CIO_MSG_EVENT(4, "recovery: schedule\n");
1324         spin_lock_irqsave(&recovery_lock, flags);
1325         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1326                 recovery_phase = 0;
1327                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1328         }
1329         spin_unlock_irqrestore(&recovery_lock, flags);
1330 }
1331
1332 static int purge_fn(struct device *dev, void *data)
1333 {
1334         struct ccw_device *cdev = to_ccwdev(dev);
1335         struct ccw_dev_id *id = &cdev->private->dev_id;
1336
1337         spin_lock_irq(cdev->ccwlock);
1338         if (is_blacklisted(id->ssid, id->devno) &&
1339             (cdev->private->state == DEV_STATE_OFFLINE) &&
1340             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1341                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1342                               id->devno);
1343                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1344                 atomic_set(&cdev->private->onoff, 0);
1345         }
1346         spin_unlock_irq(cdev->ccwlock);
1347         /* Abort loop in case of pending signal. */
1348         if (signal_pending(current))
1349                 return -EINTR;
1350
1351         return 0;
1352 }
1353
1354 /**
1355  * ccw_purge_blacklisted - purge unused, blacklisted devices
1356  *
1357  * Unregister all ccw devices that are offline and on the blacklist.
1358  */
1359 int ccw_purge_blacklisted(void)
1360 {
1361         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1362         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1363         return 0;
1364 }
1365
1366 void ccw_device_set_disconnected(struct ccw_device *cdev)
1367 {
1368         if (!cdev)
1369                 return;
1370         ccw_device_set_timeout(cdev, 0);
1371         cdev->private->flags.fake_irb = 0;
1372         cdev->private->state = DEV_STATE_DISCONNECTED;
1373         if (cdev->online)
1374                 ccw_device_schedule_recovery();
1375 }
1376
1377 void ccw_device_set_notoper(struct ccw_device *cdev)
1378 {
1379         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1380
1381         CIO_TRACE_EVENT(2, "notoper");
1382         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1383         ccw_device_set_timeout(cdev, 0);
1384         cio_disable_subchannel(sch);
1385         cdev->private->state = DEV_STATE_NOT_OPER;
1386 }
1387
1388 enum io_sch_action {
1389         IO_SCH_UNREG,
1390         IO_SCH_ORPH_UNREG,
1391         IO_SCH_ATTACH,
1392         IO_SCH_UNREG_ATTACH,
1393         IO_SCH_ORPH_ATTACH,
1394         IO_SCH_REPROBE,
1395         IO_SCH_VERIFY,
1396         IO_SCH_DISC,
1397         IO_SCH_NOP,
1398 };
1399
1400 static enum io_sch_action sch_get_action(struct subchannel *sch)
1401 {
1402         struct ccw_device *cdev;
1403
1404         cdev = sch_get_cdev(sch);
1405         if (cio_update_schib(sch)) {
1406                 /* Not operational. */
1407                 if (!cdev)
1408                         return IO_SCH_UNREG;
1409                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1410                         return IO_SCH_UNREG;
1411                 return IO_SCH_ORPH_UNREG;
1412         }
1413         /* Operational. */
1414         if (!cdev)
1415                 return IO_SCH_ATTACH;
1416         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1417                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1418                         return IO_SCH_UNREG_ATTACH;
1419                 return IO_SCH_ORPH_ATTACH;
1420         }
1421         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1422                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1423                         return IO_SCH_UNREG;
1424                 return IO_SCH_DISC;
1425         }
1426         if (device_is_disconnected(cdev))
1427                 return IO_SCH_REPROBE;
1428         if (cdev->online)
1429                 return IO_SCH_VERIFY;
1430         return IO_SCH_NOP;
1431 }
1432
1433 /**
1434  * io_subchannel_sch_event - process subchannel event
1435  * @sch: subchannel
1436  * @process: non-zero if function is called in process context
1437  *
1438  * An unspecified event occurred for this subchannel. Adjust data according
1439  * to the current operational state of the subchannel and device. Return
1440  * zero when the event has been handled sufficiently or -EAGAIN when this
1441  * function should be called again in process context.
1442  */
1443 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1444 {
1445         unsigned long flags;
1446         struct ccw_device *cdev;
1447         struct ccw_dev_id dev_id;
1448         enum io_sch_action action;
1449         int rc = -EAGAIN;
1450
1451         spin_lock_irqsave(sch->lock, flags);
1452         if (!device_is_registered(&sch->dev))
1453                 goto out_unlock;
1454         if (work_pending(&sch->todo_work))
1455                 goto out_unlock;
1456         cdev = sch_get_cdev(sch);
1457         if (cdev && work_pending(&cdev->private->todo_work))
1458                 goto out_unlock;
1459         action = sch_get_action(sch);
1460         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1461                       sch->schid.ssid, sch->schid.sch_no, process,
1462                       action);
1463         /* Perform immediate actions while holding the lock. */
1464         switch (action) {
1465         case IO_SCH_REPROBE:
1466                 /* Trigger device recognition. */
1467                 ccw_device_trigger_reprobe(cdev);
1468                 rc = 0;
1469                 goto out_unlock;
1470         case IO_SCH_VERIFY:
1471                 if (cdev->private->flags.resuming == 1) {
1472                         if (cio_enable_subchannel(sch, (u32)(addr_t)sch)) {
1473                                 ccw_device_set_notoper(cdev);
1474                                 break;
1475                         }
1476                 }
1477                 /* Trigger path verification. */
1478                 io_subchannel_verify(sch);
1479                 rc = 0;
1480                 goto out_unlock;
1481         case IO_SCH_DISC:
1482                 ccw_device_set_disconnected(cdev);
1483                 rc = 0;
1484                 goto out_unlock;
1485         case IO_SCH_ORPH_UNREG:
1486         case IO_SCH_ORPH_ATTACH:
1487                 ccw_device_set_disconnected(cdev);
1488                 break;
1489         case IO_SCH_UNREG_ATTACH:
1490         case IO_SCH_UNREG:
1491                 if (!cdev)
1492                         break;
1493                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1494                         /*
1495                          * Note: delayed work triggered by this event
1496                          * and repeated calls to sch_event are synchronized
1497                          * by the above check for work_pending(cdev).
1498                          */
1499                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1500                 } else
1501                         ccw_device_set_notoper(cdev);
1502                 break;
1503         case IO_SCH_NOP:
1504                 rc = 0;
1505                 goto out_unlock;
1506         default:
1507                 break;
1508         }
1509         spin_unlock_irqrestore(sch->lock, flags);
1510         /* All other actions require process context. */
1511         if (!process)
1512                 goto out;
1513         /* Handle attached ccw device. */
1514         switch (action) {
1515         case IO_SCH_ORPH_UNREG:
1516         case IO_SCH_ORPH_ATTACH:
1517                 /* Move ccw device to orphanage. */
1518                 rc = ccw_device_move_to_orph(cdev);
1519                 if (rc)
1520                         goto out;
1521                 break;
1522         case IO_SCH_UNREG_ATTACH:
1523                 if (cdev->private->flags.resuming) {
1524                         /* Device will be handled later. */
1525                         rc = 0;
1526                         goto out;
1527                 }
1528                 /* Unregister ccw device. */
1529                 ccw_device_unregister(cdev);
1530                 break;
1531         default:
1532                 break;
1533         }
1534         /* Handle subchannel. */
1535         switch (action) {
1536         case IO_SCH_ORPH_UNREG:
1537         case IO_SCH_UNREG:
1538                 if (!cdev || !cdev->private->flags.resuming)
1539                         css_sch_device_unregister(sch);
1540                 break;
1541         case IO_SCH_ORPH_ATTACH:
1542         case IO_SCH_UNREG_ATTACH:
1543         case IO_SCH_ATTACH:
1544                 dev_id.ssid = sch->schid.ssid;
1545                 dev_id.devno = sch->schib.pmcw.dev;
1546                 cdev = get_ccwdev_by_dev_id(&dev_id);
1547                 if (!cdev) {
1548                         sch_create_and_recog_new_device(sch);
1549                         break;
1550                 }
1551                 rc = ccw_device_move_to_sch(cdev, sch);
1552                 if (rc) {
1553                         /* Release reference from get_ccwdev_by_dev_id() */
1554                         put_device(&cdev->dev);
1555                         goto out;
1556                 }
1557                 spin_lock_irqsave(sch->lock, flags);
1558                 ccw_device_trigger_reprobe(cdev);
1559                 spin_unlock_irqrestore(sch->lock, flags);
1560                 /* Release reference from get_ccwdev_by_dev_id() */
1561                 put_device(&cdev->dev);
1562                 break;
1563         default:
1564                 break;
1565         }
1566         return 0;
1567
1568 out_unlock:
1569         spin_unlock_irqrestore(sch->lock, flags);
1570 out:
1571         return rc;
1572 }
1573
1574 #ifdef CONFIG_CCW_CONSOLE
1575 static struct ccw_device console_cdev;
1576 static struct ccw_device_private console_private;
1577 static int console_cdev_in_use;
1578
1579 static DEFINE_SPINLOCK(ccw_console_lock);
1580
1581 spinlock_t * cio_get_console_lock(void)
1582 {
1583         return &ccw_console_lock;
1584 }
1585
1586 static int ccw_device_console_enable(struct ccw_device *cdev,
1587                                      struct subchannel *sch)
1588 {
1589         struct io_subchannel_private *io_priv = cio_get_console_priv();
1590         int rc;
1591
1592         /* Attach subchannel private data. */
1593         memset(io_priv, 0, sizeof(*io_priv));
1594         set_io_private(sch, io_priv);
1595         io_subchannel_init_fields(sch);
1596         rc = cio_commit_config(sch);
1597         if (rc)
1598                 return rc;
1599         sch->driver = &io_subchannel_driver;
1600         /* Initialize the ccw_device structure. */
1601         cdev->dev.parent= &sch->dev;
1602         sch_set_cdev(sch, cdev);
1603         io_subchannel_recog(cdev, sch);
1604         /* Now wait for the async. recognition to come to an end. */
1605         spin_lock_irq(cdev->ccwlock);
1606         while (!dev_fsm_final_state(cdev))
1607                 wait_cons_dev();
1608         rc = -EIO;
1609         if (cdev->private->state != DEV_STATE_OFFLINE)
1610                 goto out_unlock;
1611         ccw_device_online(cdev);
1612         while (!dev_fsm_final_state(cdev))
1613                 wait_cons_dev();
1614         if (cdev->private->state != DEV_STATE_ONLINE)
1615                 goto out_unlock;
1616         rc = 0;
1617 out_unlock:
1618         spin_unlock_irq(cdev->ccwlock);
1619         return rc;
1620 }
1621
1622 struct ccw_device *
1623 ccw_device_probe_console(void)
1624 {
1625         struct subchannel *sch;
1626         int ret;
1627
1628         if (xchg(&console_cdev_in_use, 1) != 0)
1629                 return ERR_PTR(-EBUSY);
1630         sch = cio_probe_console();
1631         if (IS_ERR(sch)) {
1632                 console_cdev_in_use = 0;
1633                 return (void *) sch;
1634         }
1635         memset(&console_cdev, 0, sizeof(struct ccw_device));
1636         memset(&console_private, 0, sizeof(struct ccw_device_private));
1637         console_cdev.private = &console_private;
1638         console_private.cdev = &console_cdev;
1639         console_private.int_class = IOINT_CIO;
1640         ret = ccw_device_console_enable(&console_cdev, sch);
1641         if (ret) {
1642                 cio_release_console();
1643                 console_cdev_in_use = 0;
1644                 return ERR_PTR(ret);
1645         }
1646         console_cdev.online = 1;
1647         return &console_cdev;
1648 }
1649
1650 static int ccw_device_pm_restore(struct device *dev);
1651
1652 int ccw_device_force_console(void)
1653 {
1654         if (!console_cdev_in_use)
1655                 return -ENODEV;
1656         return ccw_device_pm_restore(&console_cdev.dev);
1657 }
1658 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1659 #endif
1660
1661 /*
1662  * get ccw_device matching the busid, but only if owned by cdrv
1663  */
1664 static int
1665 __ccwdev_check_busid(struct device *dev, void *id)
1666 {
1667         char *bus_id;
1668
1669         bus_id = id;
1670
1671         return (strcmp(bus_id, dev_name(dev)) == 0);
1672 }
1673
1674
1675 /**
1676  * get_ccwdev_by_busid() - obtain device from a bus id
1677  * @cdrv: driver the device is owned by
1678  * @bus_id: bus id of the device to be searched
1679  *
1680  * This function searches all devices owned by @cdrv for a device with a bus
1681  * id matching @bus_id.
1682  * Returns:
1683  *  If a match is found, its reference count of the found device is increased
1684  *  and it is returned; else %NULL is returned.
1685  */
1686 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1687                                        const char *bus_id)
1688 {
1689         struct device *dev;
1690
1691         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1692                                  __ccwdev_check_busid);
1693
1694         return dev ? to_ccwdev(dev) : NULL;
1695 }
1696
1697 /************************** device driver handling ************************/
1698
1699 /* This is the implementation of the ccw_driver class. The probe, remove
1700  * and release methods are initially very similar to the device_driver
1701  * implementations, with the difference that they have ccw_device
1702  * arguments.
1703  *
1704  * A ccw driver also contains the information that is needed for
1705  * device matching.
1706  */
1707 static int
1708 ccw_device_probe (struct device *dev)
1709 {
1710         struct ccw_device *cdev = to_ccwdev(dev);
1711         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1712         int ret;
1713
1714         cdev->drv = cdrv; /* to let the driver call _set_online */
1715         /* Note: we interpret class 0 in this context as an uninitialized
1716          * field since it translates to a non-I/O interrupt class. */
1717         if (cdrv->int_class != 0)
1718                 cdev->private->int_class = cdrv->int_class;
1719         else
1720                 cdev->private->int_class = IOINT_CIO;
1721
1722         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1723
1724         if (ret) {
1725                 cdev->drv = NULL;
1726                 cdev->private->int_class = IOINT_CIO;
1727                 return ret;
1728         }
1729
1730         return 0;
1731 }
1732
1733 static int
1734 ccw_device_remove (struct device *dev)
1735 {
1736         struct ccw_device *cdev = to_ccwdev(dev);
1737         struct ccw_driver *cdrv = cdev->drv;
1738         int ret;
1739
1740         if (cdrv->remove)
1741                 cdrv->remove(cdev);
1742         if (cdev->online) {
1743                 cdev->online = 0;
1744                 spin_lock_irq(cdev->ccwlock);
1745                 ret = ccw_device_offline(cdev);
1746                 spin_unlock_irq(cdev->ccwlock);
1747                 if (ret == 0)
1748                         wait_event(cdev->private->wait_q,
1749                                    dev_fsm_final_state(cdev));
1750                 else
1751                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1752                                       "device 0.%x.%04x\n",
1753                                       ret, cdev->private->dev_id.ssid,
1754                                       cdev->private->dev_id.devno);
1755                 /* Give up reference obtained in ccw_device_set_online(). */
1756                 put_device(&cdev->dev);
1757         }
1758         ccw_device_set_timeout(cdev, 0);
1759         cdev->drv = NULL;
1760         cdev->private->int_class = IOINT_CIO;
1761         return 0;
1762 }
1763
1764 static void ccw_device_shutdown(struct device *dev)
1765 {
1766         struct ccw_device *cdev;
1767
1768         cdev = to_ccwdev(dev);
1769         if (cdev->drv && cdev->drv->shutdown)
1770                 cdev->drv->shutdown(cdev);
1771         disable_cmf(cdev);
1772 }
1773
1774 static int ccw_device_pm_prepare(struct device *dev)
1775 {
1776         struct ccw_device *cdev = to_ccwdev(dev);
1777
1778         if (work_pending(&cdev->private->todo_work))
1779                 return -EAGAIN;
1780         /* Fail while device is being set online/offline. */
1781         if (atomic_read(&cdev->private->onoff))
1782                 return -EAGAIN;
1783
1784         if (cdev->online && cdev->drv && cdev->drv->prepare)
1785                 return cdev->drv->prepare(cdev);
1786
1787         return 0;
1788 }
1789
1790 static void ccw_device_pm_complete(struct device *dev)
1791 {
1792         struct ccw_device *cdev = to_ccwdev(dev);
1793
1794         if (cdev->online && cdev->drv && cdev->drv->complete)
1795                 cdev->drv->complete(cdev);
1796 }
1797
1798 static int ccw_device_pm_freeze(struct device *dev)
1799 {
1800         struct ccw_device *cdev = to_ccwdev(dev);
1801         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1802         int ret, cm_enabled;
1803
1804         /* Fail suspend while device is in transistional state. */
1805         if (!dev_fsm_final_state(cdev))
1806                 return -EAGAIN;
1807         if (!cdev->online)
1808                 return 0;
1809         if (cdev->drv && cdev->drv->freeze) {
1810                 ret = cdev->drv->freeze(cdev);
1811                 if (ret)
1812                         return ret;
1813         }
1814
1815         spin_lock_irq(sch->lock);
1816         cm_enabled = cdev->private->cmb != NULL;
1817         spin_unlock_irq(sch->lock);
1818         if (cm_enabled) {
1819                 /* Don't have the css write on memory. */
1820                 ret = ccw_set_cmf(cdev, 0);
1821                 if (ret)
1822                         return ret;
1823         }
1824         /* From here on, disallow device driver I/O. */
1825         spin_lock_irq(sch->lock);
1826         ret = cio_disable_subchannel(sch);
1827         spin_unlock_irq(sch->lock);
1828
1829         return ret;
1830 }
1831
1832 static int ccw_device_pm_thaw(struct device *dev)
1833 {
1834         struct ccw_device *cdev = to_ccwdev(dev);
1835         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1836         int ret, cm_enabled;
1837
1838         if (!cdev->online)
1839                 return 0;
1840
1841         spin_lock_irq(sch->lock);
1842         /* Allow device driver I/O again. */
1843         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1844         cm_enabled = cdev->private->cmb != NULL;
1845         spin_unlock_irq(sch->lock);
1846         if (ret)
1847                 return ret;
1848
1849         if (cm_enabled) {
1850                 ret = ccw_set_cmf(cdev, 1);
1851                 if (ret)
1852                         return ret;
1853         }
1854
1855         if (cdev->drv && cdev->drv->thaw)
1856                 ret = cdev->drv->thaw(cdev);
1857
1858         return ret;
1859 }
1860
1861 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1862 {
1863         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1864
1865         spin_lock_irq(sch->lock);
1866         if (cio_is_console(sch->schid)) {
1867                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1868                 goto out_unlock;
1869         }
1870         /*
1871          * While we were sleeping, devices may have gone or become
1872          * available again. Kick re-detection.
1873          */
1874         cdev->private->flags.resuming = 1;
1875         cdev->private->path_new_mask = LPM_ANYPATH;
1876         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1877         spin_unlock_irq(sch->lock);
1878         css_wait_for_slow_path();
1879
1880         /* cdev may have been moved to a different subchannel. */
1881         sch = to_subchannel(cdev->dev.parent);
1882         spin_lock_irq(sch->lock);
1883         if (cdev->private->state != DEV_STATE_ONLINE &&
1884             cdev->private->state != DEV_STATE_OFFLINE)
1885                 goto out_unlock;
1886
1887         ccw_device_recognition(cdev);
1888         spin_unlock_irq(sch->lock);
1889         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1890                    cdev->private->state == DEV_STATE_DISCONNECTED);
1891         spin_lock_irq(sch->lock);
1892
1893 out_unlock:
1894         cdev->private->flags.resuming = 0;
1895         spin_unlock_irq(sch->lock);
1896 }
1897
1898 static int resume_handle_boxed(struct ccw_device *cdev)
1899 {
1900         cdev->private->state = DEV_STATE_BOXED;
1901         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1902                 return 0;
1903         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1904         return -ENODEV;
1905 }
1906
1907 static int resume_handle_disc(struct ccw_device *cdev)
1908 {
1909         cdev->private->state = DEV_STATE_DISCONNECTED;
1910         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1911                 return 0;
1912         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1913         return -ENODEV;
1914 }
1915
1916 static int ccw_device_pm_restore(struct device *dev)
1917 {
1918         struct ccw_device *cdev = to_ccwdev(dev);
1919         struct subchannel *sch;
1920         int ret = 0;
1921
1922         __ccw_device_pm_restore(cdev);
1923         sch = to_subchannel(cdev->dev.parent);
1924         spin_lock_irq(sch->lock);
1925         if (cio_is_console(sch->schid))
1926                 goto out_restore;
1927
1928         /* check recognition results */
1929         switch (cdev->private->state) {
1930         case DEV_STATE_OFFLINE:
1931         case DEV_STATE_ONLINE:
1932                 cdev->private->flags.donotify = 0;
1933                 break;
1934         case DEV_STATE_BOXED:
1935                 ret = resume_handle_boxed(cdev);
1936                 if (ret)
1937                         goto out_unlock;
1938                 goto out_restore;
1939         default:
1940                 ret = resume_handle_disc(cdev);
1941                 if (ret)
1942                         goto out_unlock;
1943                 goto out_restore;
1944         }
1945         /* check if the device type has changed */
1946         if (!ccw_device_test_sense_data(cdev)) {
1947                 ccw_device_update_sense_data(cdev);
1948                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1949                 ret = -ENODEV;
1950                 goto out_unlock;
1951         }
1952         if (!cdev->online)
1953                 goto out_unlock;
1954
1955         if (ccw_device_online(cdev)) {
1956                 ret = resume_handle_disc(cdev);
1957                 if (ret)
1958                         goto out_unlock;
1959                 goto out_restore;
1960         }
1961         spin_unlock_irq(sch->lock);
1962         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1963         spin_lock_irq(sch->lock);
1964
1965         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1966                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1967                 ret = -ENODEV;
1968                 goto out_unlock;
1969         }
1970
1971         /* reenable cmf, if needed */
1972         if (cdev->private->cmb) {
1973                 spin_unlock_irq(sch->lock);
1974                 ret = ccw_set_cmf(cdev, 1);
1975                 spin_lock_irq(sch->lock);
1976                 if (ret) {
1977                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1978                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
1979                                       cdev->private->dev_id.devno, ret);
1980                         ret = 0;
1981                 }
1982         }
1983
1984 out_restore:
1985         spin_unlock_irq(sch->lock);
1986         if (cdev->online && cdev->drv && cdev->drv->restore)
1987                 ret = cdev->drv->restore(cdev);
1988         return ret;
1989
1990 out_unlock:
1991         spin_unlock_irq(sch->lock);
1992         return ret;
1993 }
1994
1995 static const struct dev_pm_ops ccw_pm_ops = {
1996         .prepare = ccw_device_pm_prepare,
1997         .complete = ccw_device_pm_complete,
1998         .freeze = ccw_device_pm_freeze,
1999         .thaw = ccw_device_pm_thaw,
2000         .restore = ccw_device_pm_restore,
2001 };
2002
2003 static struct bus_type ccw_bus_type = {
2004         .name   = "ccw",
2005         .match  = ccw_bus_match,
2006         .uevent = ccw_uevent,
2007         .probe  = ccw_device_probe,
2008         .remove = ccw_device_remove,
2009         .shutdown = ccw_device_shutdown,
2010         .pm = &ccw_pm_ops,
2011 };
2012
2013 /**
2014  * ccw_driver_register() - register a ccw driver
2015  * @cdriver: driver to be registered
2016  *
2017  * This function is mainly a wrapper around driver_register().
2018  * Returns:
2019  *   %0 on success and a negative error value on failure.
2020  */
2021 int ccw_driver_register(struct ccw_driver *cdriver)
2022 {
2023         struct device_driver *drv = &cdriver->driver;
2024
2025         drv->bus = &ccw_bus_type;
2026
2027         return driver_register(drv);
2028 }
2029
2030 /**
2031  * ccw_driver_unregister() - deregister a ccw driver
2032  * @cdriver: driver to be deregistered
2033  *
2034  * This function is mainly a wrapper around driver_unregister().
2035  */
2036 void ccw_driver_unregister(struct ccw_driver *cdriver)
2037 {
2038         driver_unregister(&cdriver->driver);
2039 }
2040
2041 /* Helper func for qdio. */
2042 struct subchannel_id
2043 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2044 {
2045         struct subchannel *sch;
2046
2047         sch = to_subchannel(cdev->dev.parent);
2048         return sch->schid;
2049 }
2050
2051 static void ccw_device_todo(struct work_struct *work)
2052 {
2053         struct ccw_device_private *priv;
2054         struct ccw_device *cdev;
2055         struct subchannel *sch;
2056         enum cdev_todo todo;
2057
2058         priv = container_of(work, struct ccw_device_private, todo_work);
2059         cdev = priv->cdev;
2060         sch = to_subchannel(cdev->dev.parent);
2061         /* Find out todo. */
2062         spin_lock_irq(cdev->ccwlock);
2063         todo = priv->todo;
2064         priv->todo = CDEV_TODO_NOTHING;
2065         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2066                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2067         spin_unlock_irq(cdev->ccwlock);
2068         /* Perform todo. */
2069         switch (todo) {
2070         case CDEV_TODO_ENABLE_CMF:
2071                 cmf_reenable(cdev);
2072                 break;
2073         case CDEV_TODO_REBIND:
2074                 ccw_device_do_unbind_bind(cdev);
2075                 break;
2076         case CDEV_TODO_REGISTER:
2077                 io_subchannel_register(cdev);
2078                 break;
2079         case CDEV_TODO_UNREG_EVAL:
2080                 if (!sch_is_pseudo_sch(sch))
2081                         css_schedule_eval(sch->schid);
2082                 /* fall-through */
2083         case CDEV_TODO_UNREG:
2084                 if (sch_is_pseudo_sch(sch))
2085                         ccw_device_unregister(cdev);
2086                 else
2087                         ccw_device_call_sch_unregister(cdev);
2088                 break;
2089         default:
2090                 break;
2091         }
2092         /* Release workqueue ref. */
2093         put_device(&cdev->dev);
2094 }
2095
2096 /**
2097  * ccw_device_sched_todo - schedule ccw device operation
2098  * @cdev: ccw device
2099  * @todo: todo
2100  *
2101  * Schedule the operation identified by @todo to be performed on the slow path
2102  * workqueue. Do nothing if another operation with higher priority is already
2103  * scheduled. Needs to be called with ccwdev lock held.
2104  */
2105 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2106 {
2107         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2108                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2109                       todo);
2110         if (cdev->private->todo >= todo)
2111                 return;
2112         cdev->private->todo = todo;
2113         /* Get workqueue ref. */
2114         if (!get_device(&cdev->dev))
2115                 return;
2116         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2117                 /* Already queued, release workqueue ref. */
2118                 put_device(&cdev->dev);
2119         }
2120 }
2121
2122 /**
2123  * ccw_device_siosl() - initiate logging
2124  * @cdev: ccw device
2125  *
2126  * This function is used to invoke model-dependent logging within the channel
2127  * subsystem.
2128  */
2129 int ccw_device_siosl(struct ccw_device *cdev)
2130 {
2131         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2132
2133         return chsc_siosl(sch->schid);
2134 }
2135 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2136
2137 MODULE_LICENSE("GPL");
2138 EXPORT_SYMBOL(ccw_device_set_online);
2139 EXPORT_SYMBOL(ccw_device_set_offline);
2140 EXPORT_SYMBOL(ccw_driver_register);
2141 EXPORT_SYMBOL(ccw_driver_unregister);
2142 EXPORT_SYMBOL(get_ccwdev_by_busid);
2143 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);