drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *   $Revision: 1.115 $
   5  *
   6  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
   7  *                       IBM Corporation
   8  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   9  *               Cornelia Huck (cohuck@de.ibm.com)
  10  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
  11  */
  12 #include <linux/config.h>
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/list.h>
  20 #include <linux/device.h>
  21 #include <linux/workqueue.h>
  22
  23 #include <asm/ccwdev.h>
  24 #include <asm/cio.h>
  25
  26 #include "cio.h"
  27 #include "css.h"
  28 #include "device.h"
  29
  30 /******************* bus type handling ***********************/
  31
  32 /* The Linux driver model distinguishes between a bus type and
  33  * the bus itself. Of course we only have one channel
  34  * subsystem driver and one channel system per machine, but
  35  * we still use the abstraction. T.R. says it's a good idea. */
  36 static int
  37 ccw_bus_match (struct device * dev, struct device_driver * drv)
  38 {
  39         struct ccw_device *cdev = to_ccwdev(dev);
  40         struct ccw_driver *cdrv = to_ccwdrv(drv);
  41         const struct ccw_device_id *ids = cdrv->ids, *found;
  42
  43         if (!ids)
  44                 return 0;
  45
  46         found = ccw_device_id_match(ids, &cdev->id);
  47         if (!found)
  48                 return 0;
  49
  50         cdev->id.driver_info = found->driver_info;
  51
  52         return 1;
  53 }
  54
  55 /*
  56  * Hotplugging interface for ccw devices.
  57  * Heavily modeled on pci and usb hotplug.
  58  */
  59 static int
  60 ccw_hotplug (struct device *dev, char **envp, int num_envp,
  61              char *buffer, int buffer_size)
  62 {
  63         struct ccw_device *cdev = to_ccwdev(dev);
  64         int i = 0;
  65         int length = 0;
  66
  67         if (!cdev)
  68                 return -ENODEV;
  69
  70         if (cdev->private->state == DEV_STATE_NOT_OPER)
  71                 return -ENODEV;
  72
  73         /* what we want to pass to /sbin/hotplug */
  74
  75         envp[i++] = buffer;
  76         length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
  77                            cdev->id.cu_type);
  78         if ((buffer_size - length <= 0) || (i >= num_envp))
  79                 return -ENOMEM;
  80         ++length;
  81         buffer += length;
  82
  83         envp[i++] = buffer;
  84         length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
  85                            cdev->id.cu_model);
  86         if ((buffer_size - length <= 0) || (i >= num_envp))
  87                 return -ENOMEM;
  88         ++length;
  89         buffer += length;
  90
  91         /* The next two can be zero, that's ok for us */
  92         envp[i++] = buffer;
  93         length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
  94                            cdev->id.dev_type);
  95         if ((buffer_size - length <= 0) || (i >= num_envp))
  96                 return -ENOMEM;
  97         ++length;
  98         buffer += length;
  99
 100         envp[i++] = buffer;
 101         length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
 102                            cdev->id.dev_model);
 103         if ((buffer_size - length <= 0) || (i >= num_envp))
 104                 return -ENOMEM;
 105
 106         envp[i] = 0;
 107
 108         return 0;
 109 }
 110
 111 struct bus_type ccw_bus_type = {
 112         .name  = "ccw",
 113         .match = &ccw_bus_match,
 114         .hotplug = &ccw_hotplug,
 115 };
 116
 117 static int io_subchannel_probe (struct device *);
 118 static int io_subchannel_remove (struct device *);
 119 void io_subchannel_irq (struct device *);
 120 static int io_subchannel_notify(struct device *, int);
 121 static void io_subchannel_verify(struct device *);
 122 static void io_subchannel_ioterm(struct device *);
 123 static void io_subchannel_shutdown(struct device *);
 124
 125 struct css_driver io_subchannel_driver = {
 126         .subchannel_type = SUBCHANNEL_TYPE_IO,
 127         .drv = {
 128                 .name = "io_subchannel",
 129                 .bus  = &css_bus_type,
 130                 .probe = &io_subchannel_probe,
 131                 .remove = &io_subchannel_remove,
 132                 .shutdown = &io_subchannel_shutdown,
 133         },
 134         .irq = io_subchannel_irq,
 135         .notify = io_subchannel_notify,
 136         .verify = io_subchannel_verify,
 137         .termination = io_subchannel_ioterm,
 138 };
 139
 140 struct workqueue_struct *ccw_device_work;
 141 struct workqueue_struct *ccw_device_notify_work;
 142 static wait_queue_head_t ccw_device_init_wq;
 143 static atomic_t ccw_device_init_count;
 144
 145 static int __init
 146 init_ccw_bus_type (void)
 147 {
 148         int ret;
 149
 150         init_waitqueue_head(&ccw_device_init_wq);
 151         atomic_set(&ccw_device_init_count, 0);
 152
 153         ccw_device_work = create_singlethread_workqueue("cio");
 154         if (!ccw_device_work)
 155                 return -ENOMEM; /* FIXME: better errno ? */
 156         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 157         if (!ccw_device_notify_work) {
 158                 ret = -ENOMEM; /* FIXME: better errno ? */
 159                 goto out_err;
 160         }
 161         if ((ret = bus_register (&ccw_bus_type)))
 162                 goto out_err;
 163
 164         if ((ret = driver_register(&io_subchannel_driver.drv)))
 165                 goto out_err;
 166
 167         wait_event(ccw_device_init_wq,
 168                    atomic_read(&ccw_device_init_count) == 0);
 169         flush_workqueue(ccw_device_work);
 170         return 0;
 171 out_err:
 172         if (ccw_device_work)
 173                 destroy_workqueue(ccw_device_work);
 174         if (ccw_device_notify_work)
 175                 destroy_workqueue(ccw_device_notify_work);
 176         return ret;
 177 }
 178
 179 static void __exit
 180 cleanup_ccw_bus_type (void)
 181 {
 182         driver_unregister(&io_subchannel_driver.drv);
 183         bus_unregister(&ccw_bus_type);
 184         destroy_workqueue(ccw_device_notify_work);
 185         destroy_workqueue(ccw_device_work);
 186 }
 187
 188 subsys_initcall(init_ccw_bus_type);
 189 module_exit(cleanup_ccw_bus_type);
 190
 191 /************************ device handling **************************/
 192
 193 /*
 194  * A ccw_device has some interfaces in sysfs in addition to the
 195  * standard ones.
 196  * The following entries are designed to export the information which
 197  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 198  * are obvious, so they don't have an entry :)
 199  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 200  */
 201 static ssize_t
 202 chpids_show (struct device * dev, char * buf)
 203 {
 204         struct subchannel *sch = to_subchannel(dev);
 205         struct ssd_info *ssd = &sch->ssd_info;
 206         ssize_t ret = 0;
 207         int chp;
 208
 209         for (chp = 0; chp < 8; chp++)
 210                 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
 211
 212         ret += sprintf (buf+ret, "\n");
 213         return min((ssize_t)PAGE_SIZE, ret);
 214 }
 215
 216 static ssize_t
 217 pimpampom_show (struct device * dev, char * buf)
 218 {
 219         struct subchannel *sch = to_subchannel(dev);
 220         struct pmcw *pmcw = &sch->schib.pmcw;
 221
 222         return sprintf (buf, "%02x %02x %02x\n",
 223                         pmcw->pim, pmcw->pam, pmcw->pom);
 224 }
 225
 226 static ssize_t
 227 devtype_show (struct device *dev, char *buf)
 228 {
 229         struct ccw_device *cdev = to_ccwdev(dev);
 230         struct ccw_device_id *id = &(cdev->id);
 231
 232         if (id->dev_type != 0)
 233                 return sprintf(buf, "%04x/%02x\n",
 234                                 id->dev_type, id->dev_model);
 235         else
 236                 return sprintf(buf, "n/a\n");
 237 }
 238
 239 static ssize_t
 240 cutype_show (struct device *dev, char *buf)
 241 {
 242         struct ccw_device *cdev = to_ccwdev(dev);
 243         struct ccw_device_id *id = &(cdev->id);
 244
 245         return sprintf(buf, "%04x/%02x\n",
 246                        id->cu_type, id->cu_model);
 247 }
 248
 249 static ssize_t
 250 online_show (struct device *dev, char *buf)
 251 {
 252         struct ccw_device *cdev = to_ccwdev(dev);
 253
 254         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 255 }
 256
 257 static void
 258 ccw_device_remove_disconnected(struct ccw_device *cdev)
 259 {
 260         struct subchannel *sch;
 261         /*
 262          * Forced offline in disconnected state means
 263          * 'throw away device'.
 264          */
 265         sch = to_subchannel(cdev->dev.parent);
 266         device_unregister(&sch->dev);
 267         /* Reset intparm to zeroes. */
 268         sch->schib.pmcw.intparm = 0;
 269         cio_modify(sch);
 270         put_device(&sch->dev);
 271 }
 272
 273 int
 274 ccw_device_set_offline(struct ccw_device *cdev)
 275 {
 276         int ret;
 277
 278         if (!cdev)
 279                 return -ENODEV;
 280         if (!cdev->online || !cdev->drv)
 281                 return -EINVAL;
 282
 283         if (cdev->drv->set_offline) {
 284                 ret = cdev->drv->set_offline(cdev);
 285                 if (ret != 0)
 286                         return ret;
 287         }
 288         cdev->online = 0;
 289         spin_lock_irq(cdev->ccwlock);
 290         ret = ccw_device_offline(cdev);
 291         spin_unlock_irq(cdev->ccwlock);
 292         if (ret == 0)
 293                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 294         else {
 295                 pr_debug("ccw_device_offline returned %d, device %s\n",
 296                          ret, cdev->dev.bus_id);
 297                 cdev->online = 1;
 298         }
 299         return ret;
 300 }
 301
 302 int
 303 ccw_device_set_online(struct ccw_device *cdev)
 304 {
 305         int ret;
 306
 307         if (!cdev)
 308                 return -ENODEV;
 309         if (cdev->online || !cdev->drv)
 310                 return -EINVAL;
 311
 312         spin_lock_irq(cdev->ccwlock);
 313         ret = ccw_device_online(cdev);
 314         spin_unlock_irq(cdev->ccwlock);
 315         if (ret == 0)
 316                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 317         else {
 318                 pr_debug("ccw_device_online returned %d, device %s\n",
 319                          ret, cdev->dev.bus_id);
 320                 return ret;
 321         }
 322         if (cdev->private->state != DEV_STATE_ONLINE)
 323                 return -ENODEV;
 324         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 325                 cdev->online = 1;
 326                 return 0;
 327         }
 328         spin_lock_irq(cdev->ccwlock);
 329         ret = ccw_device_offline(cdev);
 330         spin_unlock_irq(cdev->ccwlock);
 331         if (ret == 0)
 332                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 333         else
 334                 pr_debug("ccw_device_offline returned %d, device %s\n",
 335                          ret, cdev->dev.bus_id);
 336         return (ret = 0) ? -ENODEV : ret;
 337 }
 338
 339 static ssize_t
 340 online_store (struct device *dev, const char *buf, size_t count)
 341 {
 342         struct ccw_device *cdev = to_ccwdev(dev);
 343         int i, force, ret;
 344         char *tmp;
 345
 346         if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
 347                 return -EAGAIN;
 348
 349         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 350                 atomic_set(&cdev->private->onoff, 0);
 351                 return -EINVAL;
 352         }
 353         if (!strncmp(buf, "force\n", count)) {
 354                 force = 1;
 355                 i = 1;
 356         } else {
 357                 force = 0;
 358                 i = simple_strtoul(buf, &tmp, 16);
 359         }
 360         if (i == 1) {
 361                 /* Do device recognition, if needed. */
 362                 if (cdev->id.cu_type == 0) {
 363                         ret = ccw_device_recognition(cdev);
 364                         if (ret) {
 365                                 printk(KERN_WARNING"Couldn't start recognition "
 366                                        "for device %s (ret=%d)\n",
 367                                        cdev->dev.bus_id, ret);
 368                                 goto out;
 369                         }
 370                         wait_event(cdev->private->wait_q,
 371                                    cdev->private->flags.recog_done);
 372                 }
 373                 if (cdev->drv && cdev->drv->set_online)
 374                         ccw_device_set_online(cdev);
 375         } else if (i == 0) {
 376                 if (cdev->private->state == DEV_STATE_DISCONNECTED)
 377                         ccw_device_remove_disconnected(cdev);
 378                 else if (cdev->drv && cdev->drv->set_offline)
 379                         ccw_device_set_offline(cdev);
 380         }
 381         if (force && cdev->private->state == DEV_STATE_BOXED) {
 382                 ret = ccw_device_stlck(cdev);
 383                 if (ret) {
 384                         printk(KERN_WARNING"ccw_device_stlck for device %s "
 385                                "returned %d!\n", cdev->dev.bus_id, ret);
 386                         goto out;
 387                 }
 388                 /* Do device recognition, if needed. */
 389                 if (cdev->id.cu_type == 0) {
 390                         cdev->private->state = DEV_STATE_NOT_OPER;
 391                         ret = ccw_device_recognition(cdev);
 392                         if (ret) {
 393                                 printk(KERN_WARNING"Couldn't start recognition "
 394                                        "for device %s (ret=%d)\n",
 395                                        cdev->dev.bus_id, ret);
 396                                 goto out;
 397                         }
 398                         wait_event(cdev->private->wait_q,
 399                                    cdev->private->flags.recog_done);
 400                 }
 401                 if (cdev->drv && cdev->drv->set_online)
 402                         ccw_device_set_online(cdev);
 403         }
 404         out:
 405         if (cdev->drv)
 406                 module_put(cdev->drv->owner);
 407         atomic_set(&cdev->private->onoff, 0);
 408         return count;
 409 }
 410
 411 static ssize_t
 412 available_show (struct device *dev, char *buf)
 413 {
 414         struct ccw_device *cdev = to_ccwdev(dev);
 415         struct subchannel *sch;
 416
 417         switch (cdev->private->state) {
 418         case DEV_STATE_BOXED:
 419                 return sprintf(buf, "boxed\n");
 420         case DEV_STATE_DISCONNECTED:
 421         case DEV_STATE_DISCONNECTED_SENSE_ID:
 422         case DEV_STATE_NOT_OPER:
 423                 sch = to_subchannel(dev->parent);
 424                 if (!sch->lpm)
 425                         return sprintf(buf, "no path\n");
 426                 else
 427                         return sprintf(buf, "no device\n");
 428         default:
 429                 /* All other states considered fine. */
 430                 return sprintf(buf, "good\n");
 431         }
 432 }
 433
 434 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 435 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 436 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 437 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 438 static DEVICE_ATTR(online, 0644, online_show, online_store);
 439 extern struct device_attribute dev_attr_cmb_enable;
 440 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 441
 442 static struct attribute * subch_attrs[] = {
 443         &dev_attr_chpids.attr,
 444         &dev_attr_pimpampom.attr,
 445         NULL,
 446 };
 447
 448 static struct attribute_group subch_attr_group = {
 449         .attrs = subch_attrs,
 450 };
 451
 452 static inline int
 453 subchannel_add_files (struct device *dev)
 454 {
 455         return sysfs_create_group(&dev->kobj, &subch_attr_group);
 456 }
 457
 458 static struct attribute * ccwdev_attrs[] = {
 459         &dev_attr_devtype.attr,
 460         &dev_attr_cutype.attr,
 461         &dev_attr_online.attr,
 462         &dev_attr_cmb_enable.attr,
 463         &dev_attr_availability.attr,
 464         NULL,
 465 };
 466
 467 static struct attribute_group ccwdev_attr_group = {
 468         .attrs = ccwdev_attrs,
 469 };
 470
 471 static inline int
 472 device_add_files (struct device *dev)
 473 {
 474         return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
 475 }
 476
 477 static inline void
 478 device_remove_files(struct device *dev)
 479 {
 480         sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
 481 }
 482
 483 /* this is a simple abstraction for device_register that sets the
 484  * correct bus type and adds the bus specific files */
 485 int
 486 ccw_device_register(struct ccw_device *cdev)
 487 {
 488         struct device *dev = &cdev->dev;
 489         int ret;
 490
 491         dev->bus = &ccw_bus_type;
 492
 493         if ((ret = device_add(dev)))
 494                 return ret;
 495
 496         if ((ret = device_add_files(dev)))
 497                 device_del(dev);
 498
 499         return ret;
 500 }
 501
 502 void
 503 ccw_device_do_unreg_rereg(void *data)
 504 {
 505         struct device *dev;
 506
 507         dev = (struct device *)data;
 508         device_remove_files(dev);
 509         device_del(dev);
 510         if (device_add(dev)) {
 511                 put_device(dev);
 512                 return;
 513         }
 514         if (device_add_files(dev))
 515                 device_unregister(dev);
 516 }
 517
 518 static void
 519 ccw_device_release(struct device *dev)
 520 {
 521         struct ccw_device *cdev;
 522
 523         cdev = to_ccwdev(dev);
 524         kfree(cdev->private);
 525         kfree(cdev);
 526 }
 527
 528 /*
 529  * Register recognized device.
 530  */
 531 static void
 532 io_subchannel_register(void *data)
 533 {
 534         struct ccw_device *cdev;
 535         struct subchannel *sch;
 536         int ret;
 537
 538         cdev = (struct ccw_device *) data;
 539         sch = to_subchannel(cdev->dev.parent);
 540
 541         if (!list_empty(&sch->dev.children)) {
 542                 bus_rescan_devices(&ccw_bus_type);
 543                 goto out;
 544         }
 545         /* make it known to the system */
 546         ret = ccw_device_register(cdev);
 547         if (ret) {
 548                 printk (KERN_WARNING "%s: could not register %s\n",
 549                         __func__, cdev->dev.bus_id);
 550                 put_device(&cdev->dev);
 551                 sch->dev.driver_data = 0;
 552                 kfree (cdev->private);
 553                 kfree (cdev);
 554                 goto out;
 555         }
 556
 557         ret = subchannel_add_files(cdev->dev.parent);
 558         if (ret)
 559                 printk(KERN_WARNING "%s: could not add attributes to %s\n",
 560                        __func__, sch->dev.bus_id);
 561         put_device(&cdev->dev);
 562 out:
 563         cdev->private->flags.recog_done = 1;
 564         put_device(&sch->dev);
 565         wake_up(&cdev->private->wait_q);
 566 }
 567
 568 void
 569 ccw_device_call_sch_unregister(void *data)
 570 {
 571         struct ccw_device *cdev = data;
 572         struct subchannel *sch;
 573
 574         sch = to_subchannel(cdev->dev.parent);
 575         /* Check if device is registered. */
 576         if (!list_empty(&sch->dev.node))
 577                 device_unregister(&sch->dev);
 578         /* Reset intparm to zeroes. */
 579         sch->schib.pmcw.intparm = 0;
 580         cio_modify(sch);
 581         put_device(&cdev->dev);
 582         put_device(&sch->dev);
 583 }
 584
 585 /*
 586  * subchannel recognition done. Called from the state machine.
 587  */
 588 void
 589 io_subchannel_recog_done(struct ccw_device *cdev)
 590 {
 591         struct subchannel *sch;
 592
 593         if (css_init_done == 0) {
 594                 cdev->private->flags.recog_done = 1;
 595                 return;
 596         }
 597         switch (cdev->private->state) {
 598         case DEV_STATE_NOT_OPER:
 599                 cdev->private->flags.recog_done = 1;
 600                 /* Remove device found not operational. */
 601                 if (!get_device(&cdev->dev))
 602                         break;
 603                 sch = to_subchannel(cdev->dev.parent);
 604                 INIT_WORK(&cdev->private->kick_work,
 605                           ccw_device_call_sch_unregister, (void *) cdev);
 606                 queue_work(ccw_device_work, &cdev->private->kick_work);
 607                 break;
 608         case DEV_STATE_BOXED:
 609                 /* Device did not respond in time. */
 610         case DEV_STATE_OFFLINE:
 611                 /*
 612                  * We can't register the device in interrupt context so
 613                  * we schedule a work item.
 614                  */
 615                 if (!get_device(&cdev->dev))
 616                         break;
 617                 INIT_WORK(&cdev->private->kick_work,
 618                           io_subchannel_register, (void *) cdev);
 619                 queue_work(ccw_device_work, &cdev->private->kick_work);
 620                 break;
 621         }
 622         if (atomic_dec_and_test(&ccw_device_init_count))
 623                 wake_up(&ccw_device_init_wq);
 624 }
 625
 626 static int
 627 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 628 {
 629         int rc;
 630
 631         sch->dev.driver_data = cdev;
 632         sch->driver = &io_subchannel_driver;
 633         cdev->ccwlock = &sch->lock;
 634         *cdev->private = (struct ccw_device_private) {
 635                 .devno  = sch->schib.pmcw.dev,
 636                 .irq    = sch->irq,
 637                 .state  = DEV_STATE_NOT_OPER,
 638                 .cmb_list = LIST_HEAD_INIT(cdev->private->cmb_list),
 639         };
 640         init_waitqueue_head(&cdev->private->wait_q);
 641         init_timer(&cdev->private->timer);
 642
 643         /* Set an initial name for the device. */
 644         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
 645                   sch->schib.pmcw.dev);
 646
 647         /* Increase counter of devices currently in recognition. */
 648         atomic_inc(&ccw_device_init_count);
 649
 650         /* Start async. device sensing. */
 651         spin_lock_irq(&sch->lock);
 652         rc = ccw_device_recognition(cdev);
 653         spin_unlock_irq(&sch->lock);
 654         if (rc) {
 655                 if (atomic_dec_and_test(&ccw_device_init_count))
 656                         wake_up(&ccw_device_init_wq);
 657         }
 658         return rc;
 659 }
 660
 661 static int
 662 io_subchannel_probe (struct device *pdev)
 663 {
 664         struct subchannel *sch;
 665         struct ccw_device *cdev;
 666         int rc;
 667
 668         sch = to_subchannel(pdev);
 669         if (sch->dev.driver_data) {
 670                 /*
 671                  * This subchannel already has an associated ccw_device.
 672                  * Register it and exit. This happens for all early
 673                  * device, e.g. the console.
 674                  */
 675                 cdev = sch->dev.driver_data;
 676                 device_initialize(&cdev->dev);
 677                 ccw_device_register(cdev);
 678                 subchannel_add_files(&sch->dev);
 679                 /*
 680                  * Check if the device is already online. If it is
 681                  * the reference count needs to be corrected
 682                  * (see ccw_device_online and css_init_done for the
 683                  * ugly details).
 684                  */
 685                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
 686                     cdev->private->state != DEV_STATE_OFFLINE &&
 687                     cdev->private->state != DEV_STATE_BOXED)
 688                         get_device(&cdev->dev);
 689                 return 0;
 690         }
 691         cdev  = kmalloc (sizeof(*cdev), GFP_KERNEL);
 692         if (!cdev)
 693                 return -ENOMEM;
 694         memset(cdev, 0, sizeof(struct ccw_device));
 695         cdev->private = kmalloc(sizeof(struct ccw_device_private),
 696                                 GFP_KERNEL | GFP_DMA);
 697         if (!cdev->private) {
 698                 kfree(cdev);
 699                 return -ENOMEM;
 700         }
 701         memset(cdev->private, 0, sizeof(struct ccw_device_private));
 702         atomic_set(&cdev->private->onoff, 0);
 703         cdev->dev = (struct device) {
 704                 .parent = pdev,
 705                 .release = ccw_device_release,
 706         };
 707         /* Do first half of device_register. */
 708         device_initialize(&cdev->dev);
 709
 710         if (!get_device(&sch->dev)) {
 711                 if (cdev->dev.release)
 712                         cdev->dev.release(&cdev->dev);
 713                 return -ENODEV;
 714         }
 715
 716         rc = io_subchannel_recog(cdev, to_subchannel(pdev));
 717         if (rc) {
 718                 sch->dev.driver_data = 0;
 719                 if (cdev->dev.release)
 720                         cdev->dev.release(&cdev->dev);
 721         }
 722
 723         return rc;
 724 }
 725
 726 static int
 727 io_subchannel_remove (struct device *dev)
 728 {
 729         struct ccw_device *cdev;
 730
 731         if (!dev->driver_data)
 732                 return 0;
 733         cdev = dev->driver_data;
 734         /* Set ccw device to not operational and drop reference. */
 735         cdev->private->state = DEV_STATE_NOT_OPER;
 736         /*
 737          * Careful here. Our ccw device might be yet unregistered when
 738          * de-registering its subchannel (machine check during device
 739          * recognition). Better look if the subchannel has children.
 740          */
 741         if (!list_empty(&dev->children))
 742                 device_unregister(&cdev->dev);
 743         dev->driver_data = NULL;
 744         return 0;
 745 }
 746
 747 static int
 748 io_subchannel_notify(struct device *dev, int event)
 749 {
 750         struct ccw_device *cdev;
 751
 752         cdev = dev->driver_data;
 753         if (!cdev)
 754                 return 0;
 755         if (!cdev->drv)
 756                 return 0;
 757         if (!cdev->online)
 758                 return 0;
 759         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
 760 }
 761
 762 static void
 763 io_subchannel_verify(struct device *dev)
 764 {
 765         struct ccw_device *cdev;
 766
 767         cdev = dev->driver_data;
 768         if (cdev)
 769                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
 770 }
 771
 772 static void
 773 io_subchannel_ioterm(struct device *dev)
 774 {
 775         struct ccw_device *cdev;
 776
 777         cdev = dev->driver_data;
 778         if (!cdev)
 779                 return;
 780         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
 781         if (cdev->handler)
 782                 cdev->handler(cdev, cdev->private->intparm,
 783                               ERR_PTR(-EIO));
 784 }
 785
 786 static void
 787 io_subchannel_shutdown(struct device *dev)
 788 {
 789         struct subchannel *sch;
 790         struct ccw_device *cdev;
 791         int ret;
 792
 793         sch = to_subchannel(dev);
 794         cdev = dev->driver_data;
 795
 796         if (cio_is_console(sch->irq))
 797                 return;
 798         if (!sch->schib.pmcw.ena)
 799                 /* Nothing to do. */
 800                 return;
 801         ret = cio_disable_subchannel(sch);
 802         if (ret != -EBUSY)
 803                 /* Subchannel is disabled, we're done. */
 804                 return;
 805         cdev->private->state = DEV_STATE_QUIESCE;
 806         if (cdev->handler)
 807                 cdev->handler(cdev, cdev->private->intparm,
 808                               ERR_PTR(-EIO));
 809         ret = ccw_device_cancel_halt_clear(cdev);
 810         if (ret == -EBUSY) {
 811                 ccw_device_set_timeout(cdev, HZ/10);
 812                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 813         }
 814         cio_disable_subchannel(sch);
 815 }
 816
 817 #ifdef CONFIG_CCW_CONSOLE
 818 static struct ccw_device console_cdev;
 819 static struct ccw_device_private console_private;
 820 static int console_cdev_in_use;
 821
 822 static int
 823 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
 824 {
 825         int rc;
 826
 827         /* Initialize the ccw_device structure. */
 828         cdev->dev = (struct device) {
 829                 .parent = &sch->dev,
 830         };
 831         /* Initialize the subchannel structure */
 832         sch->dev.parent = &css_bus_device;
 833         sch->dev.bus = &css_bus_type;
 834
 835         rc = io_subchannel_recog(cdev, sch);
 836         if (rc)
 837                 return rc;
 838
 839         /* Now wait for the async. recognition to come to an end. */
 840         spin_lock_irq(cdev->ccwlock);
 841         while (!dev_fsm_final_state(cdev))
 842                 wait_cons_dev();
 843         rc = -EIO;
 844         if (cdev->private->state != DEV_STATE_OFFLINE)
 845                 goto out_unlock;
 846         ccw_device_online(cdev);
 847         while (!dev_fsm_final_state(cdev))
 848                 wait_cons_dev();
 849         if (cdev->private->state != DEV_STATE_ONLINE)
 850                 goto out_unlock;
 851         rc = 0;
 852 out_unlock:
 853         spin_unlock_irq(cdev->ccwlock);
 854         return 0;
 855 }
 856
 857 struct ccw_device *
 858 ccw_device_probe_console(void)
 859 {
 860         struct subchannel *sch;
 861         int ret;
 862
 863         if (xchg(&console_cdev_in_use, 1) != 0)
 864                 return NULL;
 865         sch = cio_probe_console();
 866         if (IS_ERR(sch)) {
 867                 console_cdev_in_use = 0;
 868                 return (void *) sch;
 869         }
 870         memset(&console_cdev, 0, sizeof(struct ccw_device));
 871         memset(&console_private, 0, sizeof(struct ccw_device_private));
 872         console_cdev.private = &console_private;
 873         ret = ccw_device_console_enable(&console_cdev, sch);
 874         if (ret) {
 875                 cio_release_console();
 876                 console_cdev_in_use = 0;
 877                 return ERR_PTR(ret);
 878         }
 879         console_cdev.online = 1;
 880         return &console_cdev;
 881 }
 882 #endif
 883
 884 /*
 885  * get ccw_device matching the busid, but only if owned by cdrv
 886  */
 887 struct ccw_device *
 888 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
 889 {
 890         struct device *d, *dev;
 891         struct device_driver *drv;
 892
 893         drv = get_driver(&cdrv->driver);
 894         if (!drv)
 895                 return 0;
 896
 897         down_read(&drv->bus->subsys.rwsem);
 898
 899         dev = NULL;
 900         list_for_each_entry(d, &drv->devices, driver_list) {
 901                 dev = get_device(d);
 902
 903                 if (dev && !strncmp(bus_id, dev->bus_id, BUS_ID_SIZE))
 904                         break;
 905                 else if (dev) {
 906                         put_device(dev);
 907                         dev = NULL;
 908                 }
 909         }
 910         up_read(&drv->bus->subsys.rwsem);
 911         put_driver(drv);
 912
 913         return dev ? to_ccwdev(dev) : 0;
 914 }
 915
 916 /************************** device driver handling ************************/
 917
 918 /* This is the implementation of the ccw_driver class. The probe, remove
 919  * and release methods are initially very similar to the device_driver
 920  * implementations, with the difference that they have ccw_device
 921  * arguments.
 922  *
 923  * A ccw driver also contains the information that is needed for
 924  * device matching.
 925  */
 926 static int
 927 ccw_device_probe (struct device *dev)
 928 {
 929         struct ccw_device *cdev = to_ccwdev(dev);
 930         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
 931         int ret;
 932
 933         cdev->drv = cdrv; /* to let the driver call _set_online */
 934
 935         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
 936
 937         if (ret) {
 938                 cdev->drv = 0;
 939                 return ret;
 940         }
 941
 942         return 0;
 943 }
 944
 945 static int
 946 ccw_device_remove (struct device *dev)
 947 {
 948         struct ccw_device *cdev = to_ccwdev(dev);
 949         struct ccw_driver *cdrv = cdev->drv;
 950         int ret;
 951
 952         pr_debug("removing device %s\n", cdev->dev.bus_id);
 953         if (cdrv->remove)
 954                 cdrv->remove(cdev);
 955         if (cdev->online) {
 956                 cdev->online = 0;
 957                 spin_lock_irq(cdev->ccwlock);
 958                 ret = ccw_device_offline(cdev);
 959                 spin_unlock_irq(cdev->ccwlock);
 960                 if (ret == 0)
 961                         wait_event(cdev->private->wait_q,
 962                                    dev_fsm_final_state(cdev));
 963                 else
 964                         //FIXME: we can't fail!
 965                         pr_debug("ccw_device_offline returned %d, device %s\n",
 966                                  ret, cdev->dev.bus_id);
 967         }
 968         ccw_device_set_timeout(cdev, 0);
 969         cdev->drv = 0;
 970         return 0;
 971 }
 972
 973 int
 974 ccw_driver_register (struct ccw_driver *cdriver)
 975 {
 976         struct device_driver *drv = &cdriver->driver;
 977
 978         drv->bus = &ccw_bus_type;
 979         drv->name = cdriver->name;
 980         drv->probe = ccw_device_probe;
 981         drv->remove = ccw_device_remove;
 982
 983         return driver_register(drv);
 984 }
 985
 986 void
 987 ccw_driver_unregister (struct ccw_driver *cdriver)
 988 {
 989         driver_unregister(&cdriver->driver);
 990 }
 991
 992 MODULE_LICENSE("GPL");
 993 EXPORT_SYMBOL(ccw_device_set_online);
 994 EXPORT_SYMBOL(ccw_device_set_offline);
 995 EXPORT_SYMBOL(ccw_driver_register);
 996 EXPORT_SYMBOL(ccw_driver_unregister);
 997 EXPORT_SYMBOL(get_ccwdev_by_busid);
 998 EXPORT_SYMBOL(ccw_bus_type);
 999 EXPORT_SYMBOL(ccw_device_work);
1000 EXPORT_SYMBOL(ccw_device_notify_work);