drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *
   5  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
   6  *                       IBM Corporation
   7  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   9  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
  10  */
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/errno.h>
  15 #include <linux/err.h>
  16 #include <linux/slab.h>
  17 #include <linux/list.h>
  18 #include <linux/device.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/timer.h>
  21
  22 #include <asm/ccwdev.h>
  23 #include <asm/cio.h>
  24 #include <asm/param.h>          /* HZ */
  25 #include <asm/cmb.h>
  26
  27 #include "cio.h"
  28 #include "cio_debug.h"
  29 #include "css.h"
  30 #include "device.h"
  31 #include "ioasm.h"
  32 #include "io_sch.h"
  33
  34 static struct timer_list recovery_timer;
  35 static DEFINE_SPINLOCK(recovery_lock);
  36 static int recovery_phase;
  37 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  38
  39 /******************* bus type handling ***********************/
  40
  41 /* The Linux driver model distinguishes between a bus type and
  42  * the bus itself. Of course we only have one channel
  43  * subsystem driver and one channel system per machine, but
  44  * we still use the abstraction. T.R. says it's a good idea. */
  45 static int
  46 ccw_bus_match (struct device * dev, struct device_driver * drv)
  47 {
  48         struct ccw_device *cdev = to_ccwdev(dev);
  49         struct ccw_driver *cdrv = to_ccwdrv(drv);
  50         const struct ccw_device_id *ids = cdrv->ids, *found;
  51
  52         if (!ids)
  53                 return 0;
  54
  55         found = ccw_device_id_match(ids, &cdev->id);
  56         if (!found)
  57                 return 0;
  58
  59         cdev->id.driver_info = found->driver_info;
  60
  61         return 1;
  62 }
  63
  64 /* Store modalias string delimited by prefix/suffix string into buffer with
  65  * specified size. Return length of resulting string (excluding trailing '\0')
  66  * even if string doesn't fit buffer (snprintf semantics). */
  67 static int snprint_alias(char *buf, size_t size,
  68                          struct ccw_device_id *id, const char *suffix)
  69 {
  70         int len;
  71
  72         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  73         if (len > size)
  74                 return len;
  75         buf += len;
  76         size -= len;
  77
  78         if (id->dev_type != 0)
  79                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  80                                 id->dev_model, suffix);
  81         else
  82                 len += snprintf(buf, size, "dtdm%s", suffix);
  83
  84         return len;
  85 }
  86
  87 /* Set up environment variables for ccw device uevent. Return 0 on success,
  88  * non-zero otherwise. */
  89 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  90 {
  91         struct ccw_device *cdev = to_ccwdev(dev);
  92         struct ccw_device_id *id = &(cdev->id);
  93         int ret;
  94         char modalias_buf[30];
  95
  96         /* CU_TYPE= */
  97         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
  98         if (ret)
  99                 return ret;
 100
 101         /* CU_MODEL= */
 102         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 103         if (ret)
 104                 return ret;
 105
 106         /* The next two can be zero, that's ok for us */
 107         /* DEV_TYPE= */
 108         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 109         if (ret)
 110                 return ret;
 111
 112         /* DEV_MODEL= */
 113         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 114         if (ret)
 115                 return ret;
 116
 117         /* MODALIAS=  */
 118         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 119         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 120         return ret;
 121 }
 122
 123 struct bus_type ccw_bus_type;
 124
 125 static void io_subchannel_irq(struct subchannel *);
 126 static int io_subchannel_probe(struct subchannel *);
 127 static int io_subchannel_remove(struct subchannel *);
 128 static int io_subchannel_notify(struct subchannel *, int);
 129 static void io_subchannel_verify(struct subchannel *);
 130 static void io_subchannel_ioterm(struct subchannel *);
 131 static void io_subchannel_shutdown(struct subchannel *);
 132
 133 static struct css_driver io_subchannel_driver = {
 134         .owner = THIS_MODULE,
 135         .subchannel_type = SUBCHANNEL_TYPE_IO,
 136         .name = "io_subchannel",
 137         .irq = io_subchannel_irq,
 138         .notify = io_subchannel_notify,
 139         .verify = io_subchannel_verify,
 140         .termination = io_subchannel_ioterm,
 141         .probe = io_subchannel_probe,
 142         .remove = io_subchannel_remove,
 143         .shutdown = io_subchannel_shutdown,
 144 };
 145
 146 struct workqueue_struct *ccw_device_work;
 147 struct workqueue_struct *ccw_device_notify_work;
 148 wait_queue_head_t ccw_device_init_wq;
 149 atomic_t ccw_device_init_count;
 150
 151 static void recovery_func(unsigned long data);
 152
 153 static int __init
 154 init_ccw_bus_type (void)
 155 {
 156         int ret;
 157
 158         init_waitqueue_head(&ccw_device_init_wq);
 159         atomic_set(&ccw_device_init_count, 0);
 160         setup_timer(&recovery_timer, recovery_func, 0);
 161
 162         ccw_device_work = create_singlethread_workqueue("cio");
 163         if (!ccw_device_work)
 164                 return -ENOMEM; /* FIXME: better errno ? */
 165         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 166         if (!ccw_device_notify_work) {
 167                 ret = -ENOMEM; /* FIXME: better errno ? */
 168                 goto out_err;
 169         }
 170         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 171         if (!slow_path_wq) {
 172                 ret = -ENOMEM; /* FIXME: better errno ? */
 173                 goto out_err;
 174         }
 175         if ((ret = bus_register (&ccw_bus_type)))
 176                 goto out_err;
 177
 178         ret = css_driver_register(&io_subchannel_driver);
 179         if (ret)
 180                 goto out_err;
 181
 182         wait_event(ccw_device_init_wq,
 183                    atomic_read(&ccw_device_init_count) == 0);
 184         flush_workqueue(ccw_device_work);
 185         return 0;
 186 out_err:
 187         if (ccw_device_work)
 188                 destroy_workqueue(ccw_device_work);
 189         if (ccw_device_notify_work)
 190                 destroy_workqueue(ccw_device_notify_work);
 191         if (slow_path_wq)
 192                 destroy_workqueue(slow_path_wq);
 193         return ret;
 194 }
 195
 196 static void __exit
 197 cleanup_ccw_bus_type (void)
 198 {
 199         css_driver_unregister(&io_subchannel_driver);
 200         bus_unregister(&ccw_bus_type);
 201         destroy_workqueue(ccw_device_notify_work);
 202         destroy_workqueue(ccw_device_work);
 203 }
 204
 205 subsys_initcall(init_ccw_bus_type);
 206 module_exit(cleanup_ccw_bus_type);
 207
 208 /************************ device handling **************************/
 209
 210 /*
 211  * A ccw_device has some interfaces in sysfs in addition to the
 212  * standard ones.
 213  * The following entries are designed to export the information which
 214  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 215  * are obvious, so they don't have an entry :)
 216  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 217  */
 218 static ssize_t
 219 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 220 {
 221         struct subchannel *sch = to_subchannel(dev);
 222         struct chsc_ssd_info *ssd = &sch->ssd_info;
 223         ssize_t ret = 0;
 224         int chp;
 225         int mask;
 226
 227         for (chp = 0; chp < 8; chp++) {
 228                 mask = 0x80 >> chp;
 229                 if (ssd->path_mask & mask)
 230                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 231                 else
 232                         ret += sprintf(buf + ret, "00 ");
 233         }
 234         ret += sprintf (buf+ret, "\n");
 235         return min((ssize_t)PAGE_SIZE, ret);
 236 }
 237
 238 static ssize_t
 239 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 240 {
 241         struct subchannel *sch = to_subchannel(dev);
 242         struct pmcw *pmcw = &sch->schib.pmcw;
 243
 244         return sprintf (buf, "%02x %02x %02x\n",
 245                         pmcw->pim, pmcw->pam, pmcw->pom);
 246 }
 247
 248 static ssize_t
 249 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 250 {
 251         struct ccw_device *cdev = to_ccwdev(dev);
 252         struct ccw_device_id *id = &(cdev->id);
 253
 254         if (id->dev_type != 0)
 255                 return sprintf(buf, "%04x/%02x\n",
 256                                 id->dev_type, id->dev_model);
 257         else
 258                 return sprintf(buf, "n/a\n");
 259 }
 260
 261 static ssize_t
 262 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 263 {
 264         struct ccw_device *cdev = to_ccwdev(dev);
 265         struct ccw_device_id *id = &(cdev->id);
 266
 267         return sprintf(buf, "%04x/%02x\n",
 268                        id->cu_type, id->cu_model);
 269 }
 270
 271 static ssize_t
 272 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 273 {
 274         struct ccw_device *cdev = to_ccwdev(dev);
 275         struct ccw_device_id *id = &(cdev->id);
 276         int len;
 277
 278         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 279
 280         return len > PAGE_SIZE ? PAGE_SIZE : len;
 281 }
 282
 283 static ssize_t
 284 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 285 {
 286         struct ccw_device *cdev = to_ccwdev(dev);
 287
 288         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 289 }
 290
 291 int ccw_device_is_orphan(struct ccw_device *cdev)
 292 {
 293         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 294 }
 295
 296 static void ccw_device_unregister(struct ccw_device *cdev)
 297 {
 298         if (test_and_clear_bit(1, &cdev->private->registered))
 299                 device_del(&cdev->dev);
 300 }
 301
 302 static void ccw_device_remove_orphan_cb(struct device *dev)
 303 {
 304         struct ccw_device *cdev = to_ccwdev(dev);
 305
 306         ccw_device_unregister(cdev);
 307         put_device(&cdev->dev);
 308 }
 309
 310 static void ccw_device_remove_sch_cb(struct device *dev)
 311 {
 312         struct subchannel *sch;
 313
 314         sch = to_subchannel(dev);
 315         css_sch_device_unregister(sch);
 316         /* Reset intparm to zeroes. */
 317         sch->schib.pmcw.intparm = 0;
 318         cio_modify(sch);
 319         put_device(&sch->dev);
 320 }
 321
 322 static void
 323 ccw_device_remove_disconnected(struct ccw_device *cdev)
 324 {
 325         unsigned long flags;
 326         int rc;
 327
 328         /*
 329          * Forced offline in disconnected state means
 330          * 'throw away device'.
 331          */
 332         if (ccw_device_is_orphan(cdev)) {
 333                 /*
 334                  * Deregister ccw device.
 335                  * Unfortunately, we cannot do this directly from the
 336                  * attribute method.
 337                  */
 338                 spin_lock_irqsave(cdev->ccwlock, flags);
 339                 cdev->private->state = DEV_STATE_NOT_OPER;
 340                 spin_unlock_irqrestore(cdev->ccwlock, flags);
 341                 rc = device_schedule_callback(&cdev->dev,
 342                                               ccw_device_remove_orphan_cb);
 343                 if (rc)
 344                         CIO_MSG_EVENT(2, "Couldn't unregister orphan "
 345                                       "0.%x.%04x\n",
 346                                       cdev->private->dev_id.ssid,
 347                                       cdev->private->dev_id.devno);
 348                 return;
 349         }
 350         /* Deregister subchannel, which will kill the ccw device. */
 351         rc = device_schedule_callback(cdev->dev.parent,
 352                                       ccw_device_remove_sch_cb);
 353         if (rc)
 354                 CIO_MSG_EVENT(2, "Couldn't unregister disconnected device "
 355                               "0.%x.%04x\n",
 356                               cdev->private->dev_id.ssid,
 357                               cdev->private->dev_id.devno);
 358 }
 359
 360 /**
 361  * ccw_device_set_offline() - disable a ccw device for I/O
 362  * @cdev: target ccw device
 363  *
 364  * This function calls the driver's set_offline() function for @cdev, if
 365  * given, and then disables @cdev.
 366  * Returns:
 367  *   %0 on success and a negative error value on failure.
 368  * Context:
 369  *  enabled, ccw device lock not held
 370  */
 371 int ccw_device_set_offline(struct ccw_device *cdev)
 372 {
 373         int ret;
 374
 375         if (!cdev)
 376                 return -ENODEV;
 377         if (!cdev->online || !cdev->drv)
 378                 return -EINVAL;
 379
 380         if (cdev->drv->set_offline) {
 381                 ret = cdev->drv->set_offline(cdev);
 382                 if (ret != 0)
 383                         return ret;
 384         }
 385         cdev->online = 0;
 386         spin_lock_irq(cdev->ccwlock);
 387         ret = ccw_device_offline(cdev);
 388         if (ret == -ENODEV) {
 389                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 390                         cdev->private->state = DEV_STATE_OFFLINE;
 391                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 392                 }
 393                 spin_unlock_irq(cdev->ccwlock);
 394                 return ret;
 395         }
 396         spin_unlock_irq(cdev->ccwlock);
 397         if (ret == 0)
 398                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 399         else {
 400                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 401                               "device 0.%x.%04x\n",
 402                               ret, cdev->private->dev_id.ssid,
 403                               cdev->private->dev_id.devno);
 404                 cdev->online = 1;
 405         }
 406         return ret;
 407 }
 408
 409 /**
 410  * ccw_device_set_online() - enable a ccw device for I/O
 411  * @cdev: target ccw device
 412  *
 413  * This function first enables @cdev and then calls the driver's set_online()
 414  * function for @cdev, if given. If set_online() returns an error, @cdev is
 415  * disabled again.
 416  * Returns:
 417  *   %0 on success and a negative error value on failure.
 418  * Context:
 419  *  enabled, ccw device lock not held
 420  */
 421 int ccw_device_set_online(struct ccw_device *cdev)
 422 {
 423         int ret;
 424
 425         if (!cdev)
 426                 return -ENODEV;
 427         if (cdev->online || !cdev->drv)
 428                 return -EINVAL;
 429
 430         spin_lock_irq(cdev->ccwlock);
 431         ret = ccw_device_online(cdev);
 432         spin_unlock_irq(cdev->ccwlock);
 433         if (ret == 0)
 434                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 435         else {
 436                 CIO_MSG_EVENT(2, "ccw_device_online returned %d, "
 437                               "device 0.%x.%04x\n",
 438                               ret, cdev->private->dev_id.ssid,
 439                               cdev->private->dev_id.devno);
 440                 return ret;
 441         }
 442         if (cdev->private->state != DEV_STATE_ONLINE)
 443                 return -ENODEV;
 444         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 445                 cdev->online = 1;
 446                 return 0;
 447         }
 448         spin_lock_irq(cdev->ccwlock);
 449         ret = ccw_device_offline(cdev);
 450         spin_unlock_irq(cdev->ccwlock);
 451         if (ret == 0)
 452                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 453         else
 454                 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
 455                               "device 0.%x.%04x\n",
 456                               ret, cdev->private->dev_id.ssid,
 457                               cdev->private->dev_id.devno);
 458         return (ret == 0) ? -ENODEV : ret;
 459 }
 460
 461 static void online_store_handle_offline(struct ccw_device *cdev)
 462 {
 463         if (cdev->private->state == DEV_STATE_DISCONNECTED)
 464                 ccw_device_remove_disconnected(cdev);
 465         else if (cdev->drv && cdev->drv->set_offline)
 466                 ccw_device_set_offline(cdev);
 467 }
 468
 469 static int online_store_recog_and_online(struct ccw_device *cdev)
 470 {
 471         int ret;
 472
 473         /* Do device recognition, if needed. */
 474         if (cdev->id.cu_type == 0) {
 475                 ret = ccw_device_recognition(cdev);
 476                 if (ret) {
 477                         CIO_MSG_EVENT(0, "Couldn't start recognition "
 478                                       "for device 0.%x.%04x (ret=%d)\n",
 479                                       cdev->private->dev_id.ssid,
 480                                       cdev->private->dev_id.devno, ret);
 481                         return ret;
 482                 }
 483                 wait_event(cdev->private->wait_q,
 484                            cdev->private->flags.recog_done);
 485         }
 486         if (cdev->drv && cdev->drv->set_online)
 487                 ccw_device_set_online(cdev);
 488         return 0;
 489 }
 490 static void online_store_handle_online(struct ccw_device *cdev, int force)
 491 {
 492         int ret;
 493
 494         ret = online_store_recog_and_online(cdev);
 495         if (ret)
 496                 return;
 497         if (force && cdev->private->state == DEV_STATE_BOXED) {
 498                 ret = ccw_device_stlck(cdev);
 499                 if (ret) {
 500                         dev_warn(&cdev->dev,
 501                                  "ccw_device_stlck returned %d!\n", ret);
 502                         return;
 503                 }
 504                 if (cdev->id.cu_type == 0)
 505                         cdev->private->state = DEV_STATE_NOT_OPER;
 506                 online_store_recog_and_online(cdev);
 507         }
 508
 509 }
 510
 511 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 512                              const char *buf, size_t count)
 513 {
 514         struct ccw_device *cdev = to_ccwdev(dev);
 515         int i, force;
 516         char *tmp;
 517
 518         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 519                 return -EAGAIN;
 520
 521         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 522                 atomic_set(&cdev->private->onoff, 0);
 523                 return -EINVAL;
 524         }
 525         if (!strncmp(buf, "force\n", count)) {
 526                 force = 1;
 527                 i = 1;
 528         } else {
 529                 force = 0;
 530                 i = simple_strtoul(buf, &tmp, 16);
 531         }
 532
 533         switch (i) {
 534         case 0:
 535                 online_store_handle_offline(cdev);
 536                 break;
 537         case 1:
 538                 online_store_handle_online(cdev, force);
 539                 break;
 540         default:
 541                 count = -EINVAL;
 542         }
 543         if (cdev->drv)
 544                 module_put(cdev->drv->owner);
 545         atomic_set(&cdev->private->onoff, 0);
 546         return count;
 547 }
 548
 549 static ssize_t
 550 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 551 {
 552         struct ccw_device *cdev = to_ccwdev(dev);
 553         struct subchannel *sch;
 554
 555         if (ccw_device_is_orphan(cdev))
 556                 return sprintf(buf, "no device\n");
 557         switch (cdev->private->state) {
 558         case DEV_STATE_BOXED:
 559                 return sprintf(buf, "boxed\n");
 560         case DEV_STATE_DISCONNECTED:
 561         case DEV_STATE_DISCONNECTED_SENSE_ID:
 562         case DEV_STATE_NOT_OPER:
 563                 sch = to_subchannel(dev->parent);
 564                 if (!sch->lpm)
 565                         return sprintf(buf, "no path\n");
 566                 else
 567                         return sprintf(buf, "no device\n");
 568         default:
 569                 /* All other states considered fine. */
 570                 return sprintf(buf, "good\n");
 571         }
 572 }
 573
 574 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 575 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 576 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 577 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 578 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 579 static DEVICE_ATTR(online, 0644, online_show, online_store);
 580 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 581
 582 static struct attribute * subch_attrs[] = {
 583         &dev_attr_chpids.attr,
 584         &dev_attr_pimpampom.attr,
 585         NULL,
 586 };
 587
 588 static struct attribute_group subch_attr_group = {
 589         .attrs = subch_attrs,
 590 };
 591
 592 struct attribute_group *subch_attr_groups[] = {
 593         &subch_attr_group,
 594         NULL,
 595 };
 596
 597 static struct attribute * ccwdev_attrs[] = {
 598         &dev_attr_devtype.attr,
 599         &dev_attr_cutype.attr,
 600         &dev_attr_modalias.attr,
 601         &dev_attr_online.attr,
 602         &dev_attr_cmb_enable.attr,
 603         &dev_attr_availability.attr,
 604         NULL,
 605 };
 606
 607 static struct attribute_group ccwdev_attr_group = {
 608         .attrs = ccwdev_attrs,
 609 };
 610
 611 static struct attribute_group *ccwdev_attr_groups[] = {
 612         &ccwdev_attr_group,
 613         NULL,
 614 };
 615
 616 /* this is a simple abstraction for device_register that sets the
 617  * correct bus type and adds the bus specific files */
 618 static int ccw_device_register(struct ccw_device *cdev)
 619 {
 620         struct device *dev = &cdev->dev;
 621         int ret;
 622
 623         dev->bus = &ccw_bus_type;
 624
 625         if ((ret = device_add(dev)))
 626                 return ret;
 627
 628         set_bit(1, &cdev->private->registered);
 629         return ret;
 630 }
 631
 632 struct match_data {
 633         struct ccw_dev_id dev_id;
 634         struct ccw_device * sibling;
 635 };
 636
 637 static int
 638 match_devno(struct device * dev, void * data)
 639 {
 640         struct match_data * d = data;
 641         struct ccw_device * cdev;
 642
 643         cdev = to_ccwdev(dev);
 644         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 645             !ccw_device_is_orphan(cdev) &&
 646             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
 647             (cdev != d->sibling))
 648                 return 1;
 649         return 0;
 650 }
 651
 652 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
 653                                                      struct ccw_device *sibling)
 654 {
 655         struct device *dev;
 656         struct match_data data;
 657
 658         data.dev_id = *dev_id;
 659         data.sibling = sibling;
 660         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 661
 662         return dev ? to_ccwdev(dev) : NULL;
 663 }
 664
 665 static int match_orphan(struct device *dev, void *data)
 666 {
 667         struct ccw_dev_id *dev_id;
 668         struct ccw_device *cdev;
 669
 670         dev_id = data;
 671         cdev = to_ccwdev(dev);
 672         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 673 }
 674
 675 static struct ccw_device *
 676 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
 677                               struct ccw_dev_id *dev_id)
 678 {
 679         struct device *dev;
 680
 681         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
 682                                 match_orphan);
 683
 684         return dev ? to_ccwdev(dev) : NULL;
 685 }
 686
 687 static void
 688 ccw_device_add_changed(struct work_struct *work)
 689 {
 690         struct ccw_device_private *priv;
 691         struct ccw_device *cdev;
 692
 693         priv = container_of(work, struct ccw_device_private, kick_work);
 694         cdev = priv->cdev;
 695         if (device_add(&cdev->dev)) {
 696                 put_device(&cdev->dev);
 697                 return;
 698         }
 699         set_bit(1, &cdev->private->registered);
 700 }
 701
 702 void ccw_device_do_unreg_rereg(struct work_struct *work)
 703 {
 704         struct ccw_device_private *priv;
 705         struct ccw_device *cdev;
 706         struct subchannel *sch;
 707
 708         priv = container_of(work, struct ccw_device_private, kick_work);
 709         cdev = priv->cdev;
 710         sch = to_subchannel(cdev->dev.parent);
 711
 712         ccw_device_unregister(cdev);
 713         PREPARE_WORK(&cdev->private->kick_work,
 714                      ccw_device_add_changed);
 715         queue_work(ccw_device_work, &cdev->private->kick_work);
 716 }
 717
 718 static void
 719 ccw_device_release(struct device *dev)
 720 {
 721         struct ccw_device *cdev;
 722
 723         cdev = to_ccwdev(dev);
 724         kfree(cdev->private);
 725         kfree(cdev);
 726 }
 727
 728 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 729 {
 730         struct ccw_device *cdev;
 731
 732         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 733         if (cdev) {
 734                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 735                                         GFP_KERNEL | GFP_DMA);
 736                 if (cdev->private)
 737                         return cdev;
 738         }
 739         kfree(cdev);
 740         return ERR_PTR(-ENOMEM);
 741 }
 742
 743 static int io_subchannel_initialize_dev(struct subchannel *sch,
 744                                         struct ccw_device *cdev)
 745 {
 746         cdev->private->cdev = cdev;
 747         atomic_set(&cdev->private->onoff, 0);
 748         cdev->dev.parent = &sch->dev;
 749         cdev->dev.release = ccw_device_release;
 750         INIT_WORK(&cdev->private->kick_work, NULL);
 751         cdev->dev.groups = ccwdev_attr_groups;
 752         /* Do first half of device_register. */
 753         device_initialize(&cdev->dev);
 754         if (!get_device(&sch->dev)) {
 755                 if (cdev->dev.release)
 756                         cdev->dev.release(&cdev->dev);
 757                 return -ENODEV;
 758         }
 759         return 0;
 760 }
 761
 762 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 763 {
 764         struct ccw_device *cdev;
 765         int ret;
 766
 767         cdev = io_subchannel_allocate_dev(sch);
 768         if (!IS_ERR(cdev)) {
 769                 ret = io_subchannel_initialize_dev(sch, cdev);
 770                 if (ret) {
 771                         kfree(cdev);
 772                         cdev = ERR_PTR(ret);
 773                 }
 774         }
 775         return cdev;
 776 }
 777
 778 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
 779
 780 static void sch_attach_device(struct subchannel *sch,
 781                               struct ccw_device *cdev)
 782 {
 783         css_update_ssd_info(sch);
 784         spin_lock_irq(sch->lock);
 785         sch_set_cdev(sch, cdev);
 786         cdev->private->schid = sch->schid;
 787         cdev->ccwlock = sch->lock;
 788         device_trigger_reprobe(sch);
 789         spin_unlock_irq(sch->lock);
 790 }
 791
 792 static void sch_attach_disconnected_device(struct subchannel *sch,
 793                                            struct ccw_device *cdev)
 794 {
 795         struct subchannel *other_sch;
 796         int ret;
 797
 798         other_sch = to_subchannel(get_device(cdev->dev.parent));
 799         ret = device_move(&cdev->dev, &sch->dev);
 800         if (ret) {
 801                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
 802                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 803                               cdev->private->dev_id.devno, ret);
 804                 put_device(&other_sch->dev);
 805                 return;
 806         }
 807         sch_set_cdev(other_sch, NULL);
 808         /* No need to keep a subchannel without ccw device around. */
 809         css_sch_device_unregister(other_sch);
 810         put_device(&other_sch->dev);
 811         sch_attach_device(sch, cdev);
 812 }
 813
 814 static void sch_attach_orphaned_device(struct subchannel *sch,
 815                                        struct ccw_device *cdev)
 816 {
 817         int ret;
 818
 819         /* Try to move the ccw device to its new subchannel. */
 820         ret = device_move(&cdev->dev, &sch->dev);
 821         if (ret) {
 822                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
 823                               "failed (ret=%d)!\n",
 824                               cdev->private->dev_id.ssid,
 825                               cdev->private->dev_id.devno, ret);
 826                 return;
 827         }
 828         sch_attach_device(sch, cdev);
 829 }
 830
 831 static void sch_create_and_recog_new_device(struct subchannel *sch)
 832 {
 833         struct ccw_device *cdev;
 834
 835         /* Need to allocate a new ccw device. */
 836         cdev = io_subchannel_create_ccwdev(sch);
 837         if (IS_ERR(cdev)) {
 838                 /* OK, we did everything we could... */
 839                 css_sch_device_unregister(sch);
 840                 return;
 841         }
 842         spin_lock_irq(sch->lock);
 843         sch_set_cdev(sch, cdev);
 844         spin_unlock_irq(sch->lock);
 845         /* Start recognition for the new ccw device. */
 846         if (io_subchannel_recog(cdev, sch)) {
 847                 spin_lock_irq(sch->lock);
 848                 sch_set_cdev(sch, NULL);
 849                 spin_unlock_irq(sch->lock);
 850                 if (cdev->dev.release)
 851                         cdev->dev.release(&cdev->dev);
 852                 css_sch_device_unregister(sch);
 853         }
 854 }
 855
 856
 857 void ccw_device_move_to_orphanage(struct work_struct *work)
 858 {
 859         struct ccw_device_private *priv;
 860         struct ccw_device *cdev;
 861         struct ccw_device *replacing_cdev;
 862         struct subchannel *sch;
 863         int ret;
 864         struct channel_subsystem *css;
 865         struct ccw_dev_id dev_id;
 866
 867         priv = container_of(work, struct ccw_device_private, kick_work);
 868         cdev = priv->cdev;
 869         sch = to_subchannel(cdev->dev.parent);
 870         css = to_css(sch->dev.parent);
 871         dev_id.devno = sch->schib.pmcw.dev;
 872         dev_id.ssid = sch->schid.ssid;
 873
 874         /*
 875          * Move the orphaned ccw device to the orphanage so the replacing
 876          * ccw device can take its place on the subchannel.
 877          */
 878         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
 879         if (ret) {
 880                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
 881                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
 882                               cdev->private->dev_id.devno, ret);
 883                 return;
 884         }
 885         cdev->ccwlock = css->pseudo_subchannel->lock;
 886         /*
 887          * Search for the replacing ccw device
 888          * - among the disconnected devices
 889          * - in the orphanage
 890          */
 891         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
 892         if (replacing_cdev) {
 893                 sch_attach_disconnected_device(sch, replacing_cdev);
 894                 return;
 895         }
 896         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
 897         if (replacing_cdev) {
 898                 sch_attach_orphaned_device(sch, replacing_cdev);
 899                 return;
 900         }
 901         sch_create_and_recog_new_device(sch);
 902 }
 903
 904 /*
 905  * Register recognized device.
 906  */
 907 static void
 908 io_subchannel_register(struct work_struct *work)
 909 {
 910         struct ccw_device_private *priv;
 911         struct ccw_device *cdev;
 912         struct subchannel *sch;
 913         int ret;
 914         unsigned long flags;
 915
 916         priv = container_of(work, struct ccw_device_private, kick_work);
 917         cdev = priv->cdev;
 918         sch = to_subchannel(cdev->dev.parent);
 919         css_update_ssd_info(sch);
 920         /*
 921          * io_subchannel_register() will also be called after device
 922          * recognition has been done for a boxed device (which will already
 923          * be registered). We need to reprobe since we may now have sense id
 924          * information.
 925          */
 926         if (klist_node_attached(&cdev->dev.knode_parent)) {
 927                 if (!cdev->drv) {
 928                         ret = device_reprobe(&cdev->dev);
 929                         if (ret)
 930                                 /* We can't do much here. */
 931                                 CIO_MSG_EVENT(2, "device_reprobe() returned"
 932                                               " %d for 0.%x.%04x\n", ret,
 933                                               cdev->private->dev_id.ssid,
 934                                               cdev->private->dev_id.devno);
 935                 }
 936                 goto out;
 937         }
 938         /*
 939          * Now we know this subchannel will stay, we can throw
 940          * our delayed uevent.
 941          */
 942         sch->dev.uevent_suppress = 0;
 943         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 944         /* make it known to the system */
 945         ret = ccw_device_register(cdev);
 946         if (ret) {
 947                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 948                               cdev->private->dev_id.ssid,
 949                               cdev->private->dev_id.devno, ret);
 950                 put_device(&cdev->dev);
 951                 spin_lock_irqsave(sch->lock, flags);
 952                 sch_set_cdev(sch, NULL);
 953                 spin_unlock_irqrestore(sch->lock, flags);
 954                 kfree (cdev->private);
 955                 kfree (cdev);
 956                 put_device(&sch->dev);
 957                 if (atomic_dec_and_test(&ccw_device_init_count))
 958                         wake_up(&ccw_device_init_wq);
 959                 return;
 960         }
 961         put_device(&cdev->dev);
 962 out:
 963         cdev->private->flags.recog_done = 1;
 964         put_device(&sch->dev);
 965         wake_up(&cdev->private->wait_q);
 966         if (atomic_dec_and_test(&ccw_device_init_count))
 967                 wake_up(&ccw_device_init_wq);
 968 }
 969
 970 static void ccw_device_call_sch_unregister(struct work_struct *work)
 971 {
 972         struct ccw_device_private *priv;
 973         struct ccw_device *cdev;
 974         struct subchannel *sch;
 975
 976         priv = container_of(work, struct ccw_device_private, kick_work);
 977         cdev = priv->cdev;
 978         sch = to_subchannel(cdev->dev.parent);
 979         css_sch_device_unregister(sch);
 980         /* Reset intparm to zeroes. */
 981         sch->schib.pmcw.intparm = 0;
 982         cio_modify(sch);
 983         put_device(&cdev->dev);
 984         put_device(&sch->dev);
 985 }
 986
 987 /*
 988  * subchannel recognition done. Called from the state machine.
 989  */
 990 void
 991 io_subchannel_recog_done(struct ccw_device *cdev)
 992 {
 993         struct subchannel *sch;
 994
 995         if (css_init_done == 0) {
 996                 cdev->private->flags.recog_done = 1;
 997                 return;
 998         }
 999         switch (cdev->private->state) {
1000         case DEV_STATE_NOT_OPER:
1001                 cdev->private->flags.recog_done = 1;
1002                 /* Remove device found not operational. */
1003                 if (!get_device(&cdev->dev))
1004                         break;
1005                 sch = to_subchannel(cdev->dev.parent);
1006                 PREPARE_WORK(&cdev->private->kick_work,
1007                              ccw_device_call_sch_unregister);
1008                 queue_work(slow_path_wq, &cdev->private->kick_work);
1009                 if (atomic_dec_and_test(&ccw_device_init_count))
1010                         wake_up(&ccw_device_init_wq);
1011                 break;
1012         case DEV_STATE_BOXED:
1013                 /* Device did not respond in time. */
1014         case DEV_STATE_OFFLINE:
1015                 /*
1016                  * We can't register the device in interrupt context so
1017                  * we schedule a work item.
1018                  */
1019                 if (!get_device(&cdev->dev))
1020                         break;
1021                 PREPARE_WORK(&cdev->private->kick_work,
1022                              io_subchannel_register);
1023                 queue_work(slow_path_wq, &cdev->private->kick_work);
1024                 break;
1025         }
1026 }
1027
1028 static int
1029 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1030 {
1031         int rc;
1032         struct ccw_device_private *priv;
1033
1034         sch_set_cdev(sch, cdev);
1035         sch->driver = &io_subchannel_driver;
1036         cdev->ccwlock = sch->lock;
1037
1038         /* Init private data. */
1039         priv = cdev->private;
1040         priv->dev_id.devno = sch->schib.pmcw.dev;
1041         priv->dev_id.ssid = sch->schid.ssid;
1042         priv->schid = sch->schid;
1043         priv->state = DEV_STATE_NOT_OPER;
1044         INIT_LIST_HEAD(&priv->cmb_list);
1045         init_waitqueue_head(&priv->wait_q);
1046         init_timer(&priv->timer);
1047
1048         /* Set an initial name for the device. */
1049         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1050                   sch->schid.ssid, sch->schib.pmcw.dev);
1051
1052         /* Increase counter of devices currently in recognition. */
1053         atomic_inc(&ccw_device_init_count);
1054
1055         /* Start async. device sensing. */
1056         spin_lock_irq(sch->lock);
1057         rc = ccw_device_recognition(cdev);
1058         spin_unlock_irq(sch->lock);
1059         if (rc) {
1060                 if (atomic_dec_and_test(&ccw_device_init_count))
1061                         wake_up(&ccw_device_init_wq);
1062         }
1063         return rc;
1064 }
1065
1066 static void ccw_device_move_to_sch(struct work_struct *work)
1067 {
1068         struct ccw_device_private *priv;
1069         int rc;
1070         struct subchannel *sch;
1071         struct ccw_device *cdev;
1072         struct subchannel *former_parent;
1073
1074         priv = container_of(work, struct ccw_device_private, kick_work);
1075         sch = priv->sch;
1076         cdev = priv->cdev;
1077         former_parent = ccw_device_is_orphan(cdev) ?
1078                 NULL : to_subchannel(get_device(cdev->dev.parent));
1079         mutex_lock(&sch->reg_mutex);
1080         /* Try to move the ccw device to its new subchannel. */
1081         rc = device_move(&cdev->dev, &sch->dev);
1082         mutex_unlock(&sch->reg_mutex);
1083         if (rc) {
1084                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1085                               "0.%x.%04x failed (ret=%d)!\n",
1086                               cdev->private->dev_id.ssid,
1087                               cdev->private->dev_id.devno, sch->schid.ssid,
1088                               sch->schid.sch_no, rc);
1089                 css_sch_device_unregister(sch);
1090                 goto out;
1091         }
1092         if (former_parent) {
1093                 spin_lock_irq(former_parent->lock);
1094                 sch_set_cdev(former_parent, NULL);
1095                 spin_unlock_irq(former_parent->lock);
1096                 css_sch_device_unregister(former_parent);
1097                 /* Reset intparm to zeroes. */
1098                 former_parent->schib.pmcw.intparm = 0;
1099                 cio_modify(former_parent);
1100         }
1101         sch_attach_device(sch, cdev);
1102 out:
1103         if (former_parent)
1104                 put_device(&former_parent->dev);
1105         put_device(&cdev->dev);
1106 }
1107
1108 static void io_subchannel_irq(struct subchannel *sch)
1109 {
1110         struct ccw_device *cdev;
1111
1112         cdev = sch_get_cdev(sch);
1113
1114         CIO_TRACE_EVENT(3, "IRQ");
1115         CIO_TRACE_EVENT(3, sch->dev.bus_id);
1116         if (cdev)
1117                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1118 }
1119
1120 static int
1121 io_subchannel_probe (struct subchannel *sch)
1122 {
1123         struct ccw_device *cdev;
1124         int rc;
1125         unsigned long flags;
1126         struct ccw_dev_id dev_id;
1127
1128         cdev = sch_get_cdev(sch);
1129         if (cdev) {
1130                 /*
1131                  * This subchannel already has an associated ccw_device.
1132                  * Register it and exit. This happens for all early
1133                  * device, e.g. the console.
1134                  */
1135                 cdev->dev.groups = ccwdev_attr_groups;
1136                 device_initialize(&cdev->dev);
1137                 ccw_device_register(cdev);
1138                 /*
1139                  * Check if the device is already online. If it is
1140                  * the reference count needs to be corrected
1141                  * (see ccw_device_online and css_init_done for the
1142                  * ugly details).
1143                  */
1144                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1145                     cdev->private->state != DEV_STATE_OFFLINE &&
1146                     cdev->private->state != DEV_STATE_BOXED)
1147                         get_device(&cdev->dev);
1148                 return 0;
1149         }
1150         /*
1151          * First check if a fitting device may be found amongst the
1152          * disconnected devices or in the orphanage.
1153          */
1154         dev_id.devno = sch->schib.pmcw.dev;
1155         dev_id.ssid = sch->schid.ssid;
1156         /* Allocate I/O subchannel private data. */
1157         sch->private = kzalloc(sizeof(struct io_subchannel_private),
1158                                GFP_KERNEL | GFP_DMA);
1159         if (!sch->private)
1160                 return -ENOMEM;
1161         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1162         if (!cdev)
1163                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1164                                                      &dev_id);
1165         if (cdev) {
1166                 /*
1167                  * Schedule moving the device until when we have a registered
1168                  * subchannel to move to and succeed the probe. We can
1169                  * unregister later again, when the probe is through.
1170                  */
1171                 cdev->private->sch = sch;
1172                 PREPARE_WORK(&cdev->private->kick_work,
1173                              ccw_device_move_to_sch);
1174                 queue_work(slow_path_wq, &cdev->private->kick_work);
1175                 return 0;
1176         }
1177         cdev = io_subchannel_create_ccwdev(sch);
1178         if (IS_ERR(cdev)) {
1179                 kfree(sch->private);
1180                 return PTR_ERR(cdev);
1181         }
1182         rc = io_subchannel_recog(cdev, sch);
1183         if (rc) {
1184                 spin_lock_irqsave(sch->lock, flags);
1185                 sch_set_cdev(sch, NULL);
1186                 spin_unlock_irqrestore(sch->lock, flags);
1187                 if (cdev->dev.release)
1188                         cdev->dev.release(&cdev->dev);
1189                 kfree(sch->private);
1190         }
1191
1192         return rc;
1193 }
1194
1195 static int
1196 io_subchannel_remove (struct subchannel *sch)
1197 {
1198         struct ccw_device *cdev;
1199         unsigned long flags;
1200
1201         cdev = sch_get_cdev(sch);
1202         if (!cdev)
1203                 return 0;
1204         /* Set ccw device to not operational and drop reference. */
1205         spin_lock_irqsave(cdev->ccwlock, flags);
1206         sch_set_cdev(sch, NULL);
1207         cdev->private->state = DEV_STATE_NOT_OPER;
1208         spin_unlock_irqrestore(cdev->ccwlock, flags);
1209         ccw_device_unregister(cdev);
1210         put_device(&cdev->dev);
1211         kfree(sch->private);
1212         return 0;
1213 }
1214
1215 static int io_subchannel_notify(struct subchannel *sch, int event)
1216 {
1217         struct ccw_device *cdev;
1218
1219         cdev = sch_get_cdev(sch);
1220         if (!cdev)
1221                 return 0;
1222         if (!cdev->drv)
1223                 return 0;
1224         if (!cdev->online)
1225                 return 0;
1226         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1227 }
1228
1229 static void io_subchannel_verify(struct subchannel *sch)
1230 {
1231         struct ccw_device *cdev;
1232
1233         cdev = sch_get_cdev(sch);
1234         if (cdev)
1235                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1236 }
1237
1238 static void io_subchannel_ioterm(struct subchannel *sch)
1239 {
1240         struct ccw_device *cdev;
1241
1242         cdev = sch_get_cdev(sch);
1243         if (!cdev)
1244                 return;
1245         /* Internal I/O will be retried by the interrupt handler. */
1246         if (cdev->private->flags.intretry)
1247                 return;
1248         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1249         if (cdev->handler)
1250                 cdev->handler(cdev, cdev->private->intparm,
1251                               ERR_PTR(-EIO));
1252 }
1253
1254 static void
1255 io_subchannel_shutdown(struct subchannel *sch)
1256 {
1257         struct ccw_device *cdev;
1258         int ret;
1259
1260         cdev = sch_get_cdev(sch);
1261
1262         if (cio_is_console(sch->schid))
1263                 return;
1264         if (!sch->schib.pmcw.ena)
1265                 /* Nothing to do. */
1266                 return;
1267         ret = cio_disable_subchannel(sch);
1268         if (ret != -EBUSY)
1269                 /* Subchannel is disabled, we're done. */
1270                 return;
1271         cdev->private->state = DEV_STATE_QUIESCE;
1272         if (cdev->handler)
1273                 cdev->handler(cdev, cdev->private->intparm,
1274                               ERR_PTR(-EIO));
1275         ret = ccw_device_cancel_halt_clear(cdev);
1276         if (ret == -EBUSY) {
1277                 ccw_device_set_timeout(cdev, HZ/10);
1278                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1279         }
1280         cio_disable_subchannel(sch);
1281 }
1282
1283 #ifdef CONFIG_CCW_CONSOLE
1284 static struct ccw_device console_cdev;
1285 static struct ccw_device_private console_private;
1286 static int console_cdev_in_use;
1287
1288 static DEFINE_SPINLOCK(ccw_console_lock);
1289
1290 spinlock_t * cio_get_console_lock(void)
1291 {
1292         return &ccw_console_lock;
1293 }
1294
1295 static int
1296 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1297 {
1298         int rc;
1299
1300         /* Attach subchannel private data. */
1301         sch->private = cio_get_console_priv();
1302         memset(sch->private, 0, sizeof(struct io_subchannel_private));
1303         /* Initialize the ccw_device structure. */
1304         cdev->dev.parent= &sch->dev;
1305         rc = io_subchannel_recog(cdev, sch);
1306         if (rc)
1307                 return rc;
1308
1309         /* Now wait for the async. recognition to come to an end. */
1310         spin_lock_irq(cdev->ccwlock);
1311         while (!dev_fsm_final_state(cdev))
1312                 wait_cons_dev();
1313         rc = -EIO;
1314         if (cdev->private->state != DEV_STATE_OFFLINE)
1315                 goto out_unlock;
1316         ccw_device_online(cdev);
1317         while (!dev_fsm_final_state(cdev))
1318                 wait_cons_dev();
1319         if (cdev->private->state != DEV_STATE_ONLINE)
1320                 goto out_unlock;
1321         rc = 0;
1322 out_unlock:
1323         spin_unlock_irq(cdev->ccwlock);
1324         return 0;
1325 }
1326
1327 struct ccw_device *
1328 ccw_device_probe_console(void)
1329 {
1330         struct subchannel *sch;
1331         int ret;
1332
1333         if (xchg(&console_cdev_in_use, 1) != 0)
1334                 return ERR_PTR(-EBUSY);
1335         sch = cio_probe_console();
1336         if (IS_ERR(sch)) {
1337                 console_cdev_in_use = 0;
1338                 return (void *) sch;
1339         }
1340         memset(&console_cdev, 0, sizeof(struct ccw_device));
1341         memset(&console_private, 0, sizeof(struct ccw_device_private));
1342         console_cdev.private = &console_private;
1343         console_private.cdev = &console_cdev;
1344         ret = ccw_device_console_enable(&console_cdev, sch);
1345         if (ret) {
1346                 cio_release_console();
1347                 console_cdev_in_use = 0;
1348                 return ERR_PTR(ret);
1349         }
1350         console_cdev.online = 1;
1351         return &console_cdev;
1352 }
1353 #endif
1354
1355 /*
1356  * get ccw_device matching the busid, but only if owned by cdrv
1357  */
1358 static int
1359 __ccwdev_check_busid(struct device *dev, void *id)
1360 {
1361         char *bus_id;
1362
1363         bus_id = id;
1364
1365         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1366 }
1367
1368
1369 /**
1370  * get_ccwdev_by_busid() - obtain device from a bus id
1371  * @cdrv: driver the device is owned by
1372  * @bus_id: bus id of the device to be searched
1373  *
1374  * This function searches all devices owned by @cdrv for a device with a bus
1375  * id matching @bus_id.
1376  * Returns:
1377  *  If a match is found, its reference count of the found device is increased
1378  *  and it is returned; else %NULL is returned.
1379  */
1380 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1381                                        const char *bus_id)
1382 {
1383         struct device *dev;
1384         struct device_driver *drv;
1385
1386         drv = get_driver(&cdrv->driver);
1387         if (!drv)
1388                 return NULL;
1389
1390         dev = driver_find_device(drv, NULL, (void *)bus_id,
1391                                  __ccwdev_check_busid);
1392         put_driver(drv);
1393
1394         return dev ? to_ccwdev(dev) : NULL;
1395 }
1396
1397 /************************** device driver handling ************************/
1398
1399 /* This is the implementation of the ccw_driver class. The probe, remove
1400  * and release methods are initially very similar to the device_driver
1401  * implementations, with the difference that they have ccw_device
1402  * arguments.
1403  *
1404  * A ccw driver also contains the information that is needed for
1405  * device matching.
1406  */
1407 static int
1408 ccw_device_probe (struct device *dev)
1409 {
1410         struct ccw_device *cdev = to_ccwdev(dev);
1411         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1412         int ret;
1413
1414         cdev->drv = cdrv; /* to let the driver call _set_online */
1415
1416         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1417
1418         if (ret) {
1419                 cdev->drv = NULL;
1420                 return ret;
1421         }
1422
1423         return 0;
1424 }
1425
1426 static int
1427 ccw_device_remove (struct device *dev)
1428 {
1429         struct ccw_device *cdev = to_ccwdev(dev);
1430         struct ccw_driver *cdrv = cdev->drv;
1431         int ret;
1432
1433         if (cdrv->remove)
1434                 cdrv->remove(cdev);
1435         if (cdev->online) {
1436                 cdev->online = 0;
1437                 spin_lock_irq(cdev->ccwlock);
1438                 ret = ccw_device_offline(cdev);
1439                 spin_unlock_irq(cdev->ccwlock);
1440                 if (ret == 0)
1441                         wait_event(cdev->private->wait_q,
1442                                    dev_fsm_final_state(cdev));
1443                 else
1444                         //FIXME: we can't fail!
1445                         CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1446                                       "device 0.%x.%04x\n",
1447                                       ret, cdev->private->dev_id.ssid,
1448                                       cdev->private->dev_id.devno);
1449         }
1450         ccw_device_set_timeout(cdev, 0);
1451         cdev->drv = NULL;
1452         return 0;
1453 }
1454
1455 static void ccw_device_shutdown(struct device *dev)
1456 {
1457         struct ccw_device *cdev;
1458
1459         cdev = to_ccwdev(dev);
1460         if (cdev->drv && cdev->drv->shutdown)
1461                 cdev->drv->shutdown(cdev);
1462         disable_cmf(cdev);
1463 }
1464
1465 struct bus_type ccw_bus_type = {
1466         .name   = "ccw",
1467         .match  = ccw_bus_match,
1468         .uevent = ccw_uevent,
1469         .probe  = ccw_device_probe,
1470         .remove = ccw_device_remove,
1471         .shutdown = ccw_device_shutdown,
1472 };
1473
1474 /**
1475  * ccw_driver_register() - register a ccw driver
1476  * @cdriver: driver to be registered
1477  *
1478  * This function is mainly a wrapper around driver_register().
1479  * Returns:
1480  *   %0 on success and a negative error value on failure.
1481  */
1482 int ccw_driver_register(struct ccw_driver *cdriver)
1483 {
1484         struct device_driver *drv = &cdriver->driver;
1485
1486         drv->bus = &ccw_bus_type;
1487         drv->name = cdriver->name;
1488         drv->owner = cdriver->owner;
1489
1490         return driver_register(drv);
1491 }
1492
1493 /**
1494  * ccw_driver_unregister() - deregister a ccw driver
1495  * @cdriver: driver to be deregistered
1496  *
1497  * This function is mainly a wrapper around driver_unregister().
1498  */
1499 void ccw_driver_unregister(struct ccw_driver *cdriver)
1500 {
1501         driver_unregister(&cdriver->driver);
1502 }
1503
1504 /* Helper func for qdio. */
1505 struct subchannel_id
1506 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1507 {
1508         struct subchannel *sch;
1509
1510         sch = to_subchannel(cdev->dev.parent);
1511         return sch->schid;
1512 }
1513
1514 static int recovery_check(struct device *dev, void *data)
1515 {
1516         struct ccw_device *cdev = to_ccwdev(dev);
1517         int *redo = data;
1518
1519         spin_lock_irq(cdev->ccwlock);
1520         switch (cdev->private->state) {
1521         case DEV_STATE_DISCONNECTED:
1522                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1523                               cdev->private->dev_id.ssid,
1524                               cdev->private->dev_id.devno);
1525                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1526                 *redo = 1;
1527                 break;
1528         case DEV_STATE_DISCONNECTED_SENSE_ID:
1529                 *redo = 1;
1530                 break;
1531         }
1532         spin_unlock_irq(cdev->ccwlock);
1533
1534         return 0;
1535 }
1536
1537 static void recovery_work_func(struct work_struct *unused)
1538 {
1539         int redo = 0;
1540
1541         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1542         if (redo) {
1543                 spin_lock_irq(&recovery_lock);
1544                 if (!timer_pending(&recovery_timer)) {
1545                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1546                                 recovery_phase++;
1547                         mod_timer(&recovery_timer, jiffies +
1548                                   recovery_delay[recovery_phase] * HZ);
1549                 }
1550                 spin_unlock_irq(&recovery_lock);
1551         } else
1552                 CIO_MSG_EVENT(2, "recovery: end\n");
1553 }
1554
1555 static DECLARE_WORK(recovery_work, recovery_work_func);
1556
1557 static void recovery_func(unsigned long data)
1558 {
1559         /*
1560          * We can't do our recovery in softirq context and it's not
1561          * performance critical, so we schedule it.
1562          */
1563         schedule_work(&recovery_work);
1564 }
1565
1566 void ccw_device_schedule_recovery(void)
1567 {
1568         unsigned long flags;
1569
1570         CIO_MSG_EVENT(2, "recovery: schedule\n");
1571         spin_lock_irqsave(&recovery_lock, flags);
1572         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1573                 recovery_phase = 0;
1574                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1575         }
1576         spin_unlock_irqrestore(&recovery_lock, flags);
1577 }
1578
1579 MODULE_LICENSE("GPL");
1580 EXPORT_SYMBOL(ccw_device_set_online);
1581 EXPORT_SYMBOL(ccw_device_set_offline);
1582 EXPORT_SYMBOL(ccw_driver_register);
1583 EXPORT_SYMBOL(ccw_driver_unregister);
1584 EXPORT_SYMBOL(get_ccwdev_by_busid);
1585 EXPORT_SYMBOL(ccw_bus_type);
1586 EXPORT_SYMBOL(ccw_device_work);
1587 EXPORT_SYMBOL(ccw_device_notify_work);
1588 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);