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