git.oblomov.eu Git - linux-2.6/blob - drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *   $Revision: 1.131 $
   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 #include "ioasm.h"
  30
  31 /******************* bus type handling ***********************/
  32
  33 /* The Linux driver model distinguishes between a bus type and
  34  * the bus itself. Of course we only have one channel
  35  * subsystem driver and one channel system per machine, but
  36  * we still use the abstraction. T.R. says it's a good idea. */
  37 static int
  38 ccw_bus_match (struct device * dev, struct device_driver * drv)
  39 {
  40         struct ccw_device *cdev = to_ccwdev(dev);
  41         struct ccw_driver *cdrv = to_ccwdrv(drv);
  42         const struct ccw_device_id *ids = cdrv->ids, *found;
  43
  44         if (!ids)
  45                 return 0;
  46
  47         found = ccw_device_id_match(ids, &cdev->id);
  48         if (!found)
  49                 return 0;
  50
  51         cdev->id.driver_info = found->driver_info;
  52
  53         return 1;
  54 }
  55
  56 /*
  57  * Hotplugging interface for ccw devices.
  58  * Heavily modeled on pci and usb hotplug.
  59  */
  60 static int
  61 ccw_hotplug (struct device *dev, char **envp, int num_envp,
  62              char *buffer, int buffer_size)
  63 {
  64         struct ccw_device *cdev = to_ccwdev(dev);
  65         int i = 0;
  66         int length = 0;
  67
  68         if (!cdev)
  69                 return -ENODEV;
  70
  71         /* what we want to pass to /sbin/hotplug */
  72
  73         envp[i++] = buffer;
  74         length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
  75                            cdev->id.cu_type);
  76         if ((buffer_size - length <= 0) || (i >= num_envp))
  77                 return -ENOMEM;
  78         ++length;
  79         buffer += length;
  80
  81         envp[i++] = buffer;
  82         length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
  83                            cdev->id.cu_model);
  84         if ((buffer_size - length <= 0) || (i >= num_envp))
  85                 return -ENOMEM;
  86         ++length;
  87         buffer += length;
  88
  89         /* The next two can be zero, that's ok for us */
  90         envp[i++] = buffer;
  91         length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
  92                            cdev->id.dev_type);
  93         if ((buffer_size - length <= 0) || (i >= num_envp))
  94                 return -ENOMEM;
  95         ++length;
  96         buffer += length;
  97
  98         envp[i++] = buffer;
  99         length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
 100                            cdev->id.dev_model);
 101         if ((buffer_size - length <= 0) || (i >= num_envp))
 102                 return -ENOMEM;
 103
 104         envp[i] = 0;
 105
 106         return 0;
 107 }
 108
 109 struct bus_type ccw_bus_type = {
 110         .name  = "ccw",
 111         .match = &ccw_bus_match,
 112         .hotplug = &ccw_hotplug,
 113 };
 114
 115 static int io_subchannel_probe (struct device *);
 116 static int io_subchannel_remove (struct device *);
 117 void io_subchannel_irq (struct device *);
 118 static int io_subchannel_notify(struct device *, int);
 119 static void io_subchannel_verify(struct device *);
 120 static void io_subchannel_ioterm(struct device *);
 121 static void io_subchannel_shutdown(struct device *);
 122
 123 struct css_driver io_subchannel_driver = {
 124         .subchannel_type = SUBCHANNEL_TYPE_IO,
 125         .drv = {
 126                 .name = "io_subchannel",
 127                 .bus  = &css_bus_type,
 128                 .probe = &io_subchannel_probe,
 129                 .remove = &io_subchannel_remove,
 130                 .shutdown = &io_subchannel_shutdown,
 131         },
 132         .irq = io_subchannel_irq,
 133         .notify = io_subchannel_notify,
 134         .verify = io_subchannel_verify,
 135         .termination = io_subchannel_ioterm,
 136 };
 137
 138 struct workqueue_struct *ccw_device_work;
 139 struct workqueue_struct *ccw_device_notify_work;
 140 static wait_queue_head_t ccw_device_init_wq;
 141 static atomic_t ccw_device_init_count;
 142
 143 static int __init
 144 init_ccw_bus_type (void)
 145 {
 146         int ret;
 147
 148         init_waitqueue_head(&ccw_device_init_wq);
 149         atomic_set(&ccw_device_init_count, 0);
 150
 151         ccw_device_work = create_singlethread_workqueue("cio");
 152         if (!ccw_device_work)
 153                 return -ENOMEM; /* FIXME: better errno ? */
 154         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
 155         if (!ccw_device_notify_work) {
 156                 ret = -ENOMEM; /* FIXME: better errno ? */
 157                 goto out_err;
 158         }
 159         slow_path_wq = create_singlethread_workqueue("kslowcrw");
 160         if (!slow_path_wq) {
 161                 ret = -ENOMEM; /* FIXME: better errno ? */
 162                 goto out_err;
 163         }
 164         if ((ret = bus_register (&ccw_bus_type)))
 165                 goto out_err;
 166
 167         if ((ret = driver_register(&io_subchannel_driver.drv)))
 168                 goto out_err;
 169
 170         wait_event(ccw_device_init_wq,
 171                    atomic_read(&ccw_device_init_count) == 0);
 172         flush_workqueue(ccw_device_work);
 173         return 0;
 174 out_err:
 175         if (ccw_device_work)
 176                 destroy_workqueue(ccw_device_work);
 177         if (ccw_device_notify_work)
 178                 destroy_workqueue(ccw_device_notify_work);
 179         if (slow_path_wq)
 180                 destroy_workqueue(slow_path_wq);
 181         return ret;
 182 }
 183
 184 static void __exit
 185 cleanup_ccw_bus_type (void)
 186 {
 187         driver_unregister(&io_subchannel_driver.drv);
 188         bus_unregister(&ccw_bus_type);
 189         destroy_workqueue(ccw_device_notify_work);
 190         destroy_workqueue(ccw_device_work);
 191 }
 192
 193 subsys_initcall(init_ccw_bus_type);
 194 module_exit(cleanup_ccw_bus_type);
 195
 196 /************************ device handling **************************/
 197
 198 /*
 199  * A ccw_device has some interfaces in sysfs in addition to the
 200  * standard ones.
 201  * The following entries are designed to export the information which
 202  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 203  * are obvious, so they don't have an entry :)
 204  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 205  */
 206 static ssize_t
 207 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 208 {
 209         struct subchannel *sch = to_subchannel(dev);
 210         struct ssd_info *ssd = &sch->ssd_info;
 211         ssize_t ret = 0;
 212         int chp;
 213
 214         for (chp = 0; chp < 8; chp++)
 215                 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
 216
 217         ret += sprintf (buf+ret, "\n");
 218         return min((ssize_t)PAGE_SIZE, ret);
 219 }
 220
 221 static ssize_t
 222 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 223 {
 224         struct subchannel *sch = to_subchannel(dev);
 225         struct pmcw *pmcw = &sch->schib.pmcw;
 226
 227         return sprintf (buf, "%02x %02x %02x\n",
 228                         pmcw->pim, pmcw->pam, pmcw->pom);
 229 }
 230
 231 static ssize_t
 232 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 233 {
 234         struct ccw_device *cdev = to_ccwdev(dev);
 235         struct ccw_device_id *id = &(cdev->id);
 236
 237         if (id->dev_type != 0)
 238                 return sprintf(buf, "%04x/%02x\n",
 239                                 id->dev_type, id->dev_model);
 240         else
 241                 return sprintf(buf, "n/a\n");
 242 }
 243
 244 static ssize_t
 245 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 246 {
 247         struct ccw_device *cdev = to_ccwdev(dev);
 248         struct ccw_device_id *id = &(cdev->id);
 249
 250         return sprintf(buf, "%04x/%02x\n",
 251                        id->cu_type, id->cu_model);
 252 }
 253
 254 static ssize_t
 255 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 256 {
 257         struct ccw_device *cdev = to_ccwdev(dev);
 258         struct ccw_device_id *id = &(cdev->id);
 259         int ret;
 260
 261         ret = sprintf(buf, "ccw:t%04Xm%02x",
 262                         id->cu_type, id->cu_model);
 263         if (id->dev_type != 0)
 264                 ret += sprintf(buf + ret, "dt%04Xdm%02X\n",
 265                                 id->dev_type, id->dev_model);
 266         else
 267                 ret += sprintf(buf + ret, "dtdm\n");
 268         return ret;
 269 }
 270
 271 static ssize_t
 272 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 273 {
 274         struct ccw_device *cdev = to_ccwdev(dev);
 275
 276         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 277 }
 278
 279 static void
 280 ccw_device_remove_disconnected(struct ccw_device *cdev)
 281 {
 282         struct subchannel *sch;
 283         /*
 284          * Forced offline in disconnected state means
 285          * 'throw away device'.
 286          */
 287         sch = to_subchannel(cdev->dev.parent);
 288         device_unregister(&sch->dev);
 289         /* Reset intparm to zeroes. */
 290         sch->schib.pmcw.intparm = 0;
 291         cio_modify(sch);
 292         put_device(&sch->dev);
 293 }
 294
 295 int
 296 ccw_device_set_offline(struct ccw_device *cdev)
 297 {
 298         int ret;
 299
 300         if (!cdev)
 301                 return -ENODEV;
 302         if (!cdev->online || !cdev->drv)
 303                 return -EINVAL;
 304
 305         if (cdev->drv->set_offline) {
 306                 ret = cdev->drv->set_offline(cdev);
 307                 if (ret != 0)
 308                         return ret;
 309         }
 310         cdev->online = 0;
 311         spin_lock_irq(cdev->ccwlock);
 312         ret = ccw_device_offline(cdev);
 313         if (ret == -ENODEV) {
 314                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
 315                         cdev->private->state = DEV_STATE_OFFLINE;
 316                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 317                 }
 318                 spin_unlock_irq(cdev->ccwlock);
 319                 return ret;
 320         }
 321         spin_unlock_irq(cdev->ccwlock);
 322         if (ret == 0)
 323                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 324         else {
 325                 pr_debug("ccw_device_offline returned %d, device %s\n",
 326                          ret, cdev->dev.bus_id);
 327                 cdev->online = 1;
 328         }
 329         return ret;
 330 }
 331
 332 int
 333 ccw_device_set_online(struct ccw_device *cdev)
 334 {
 335         int ret;
 336
 337         if (!cdev)
 338                 return -ENODEV;
 339         if (cdev->online || !cdev->drv)
 340                 return -EINVAL;
 341
 342         spin_lock_irq(cdev->ccwlock);
 343         ret = ccw_device_online(cdev);
 344         spin_unlock_irq(cdev->ccwlock);
 345         if (ret == 0)
 346                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 347         else {
 348                 pr_debug("ccw_device_online returned %d, device %s\n",
 349                          ret, cdev->dev.bus_id);
 350                 return ret;
 351         }
 352         if (cdev->private->state != DEV_STATE_ONLINE)
 353                 return -ENODEV;
 354         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
 355                 cdev->online = 1;
 356                 return 0;
 357         }
 358         spin_lock_irq(cdev->ccwlock);
 359         ret = ccw_device_offline(cdev);
 360         spin_unlock_irq(cdev->ccwlock);
 361         if (ret == 0)
 362                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 363         else
 364                 pr_debug("ccw_device_offline returned %d, device %s\n",
 365                          ret, cdev->dev.bus_id);
 366         return (ret = 0) ? -ENODEV : ret;
 367 }
 368
 369 static ssize_t
 370 online_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
 371 {
 372         struct ccw_device *cdev = to_ccwdev(dev);
 373         int i, force, ret;
 374         char *tmp;
 375
 376         if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
 377                 return -EAGAIN;
 378
 379         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
 380                 atomic_set(&cdev->private->onoff, 0);
 381                 return -EINVAL;
 382         }
 383         if (!strncmp(buf, "force\n", count)) {
 384                 force = 1;
 385                 i = 1;
 386         } else {
 387                 force = 0;
 388                 i = simple_strtoul(buf, &tmp, 16);
 389         }
 390         if (i == 1) {
 391                 /* Do device recognition, if needed. */
 392                 if (cdev->id.cu_type == 0) {
 393                         ret = ccw_device_recognition(cdev);
 394                         if (ret) {
 395                                 printk(KERN_WARNING"Couldn't start recognition "
 396                                        "for device %s (ret=%d)\n",
 397                                        cdev->dev.bus_id, ret);
 398                                 goto out;
 399                         }
 400                         wait_event(cdev->private->wait_q,
 401                                    cdev->private->flags.recog_done);
 402                 }
 403                 if (cdev->drv && cdev->drv->set_online)
 404                         ccw_device_set_online(cdev);
 405         } else if (i == 0) {
 406                 if (cdev->private->state == DEV_STATE_DISCONNECTED)
 407                         ccw_device_remove_disconnected(cdev);
 408                 else if (cdev->drv && cdev->drv->set_offline)
 409                         ccw_device_set_offline(cdev);
 410         }
 411         if (force && cdev->private->state == DEV_STATE_BOXED) {
 412                 ret = ccw_device_stlck(cdev);
 413                 if (ret) {
 414                         printk(KERN_WARNING"ccw_device_stlck for device %s "
 415                                "returned %d!\n", cdev->dev.bus_id, ret);
 416                         goto out;
 417                 }
 418                 /* Do device recognition, if needed. */
 419                 if (cdev->id.cu_type == 0) {
 420                         cdev->private->state = DEV_STATE_NOT_OPER;
 421                         ret = ccw_device_recognition(cdev);
 422                         if (ret) {
 423                                 printk(KERN_WARNING"Couldn't start recognition "
 424                                        "for device %s (ret=%d)\n",
 425                                        cdev->dev.bus_id, ret);
 426                                 goto out;
 427                         }
 428                         wait_event(cdev->private->wait_q,
 429                                    cdev->private->flags.recog_done);
 430                 }
 431                 if (cdev->drv && cdev->drv->set_online)
 432                         ccw_device_set_online(cdev);
 433         }
 434         out:
 435         if (cdev->drv)
 436                 module_put(cdev->drv->owner);
 437         atomic_set(&cdev->private->onoff, 0);
 438         return count;
 439 }
 440
 441 static ssize_t
 442 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 443 {
 444         struct ccw_device *cdev = to_ccwdev(dev);
 445         struct subchannel *sch;
 446
 447         switch (cdev->private->state) {
 448         case DEV_STATE_BOXED:
 449                 return sprintf(buf, "boxed\n");
 450         case DEV_STATE_DISCONNECTED:
 451         case DEV_STATE_DISCONNECTED_SENSE_ID:
 452         case DEV_STATE_NOT_OPER:
 453                 sch = to_subchannel(dev->parent);
 454                 if (!sch->lpm)
 455                         return sprintf(buf, "no path\n");
 456                 else
 457                         return sprintf(buf, "no device\n");
 458         default:
 459                 /* All other states considered fine. */
 460                 return sprintf(buf, "good\n");
 461         }
 462 }
 463
 464 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 465 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 466 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 467 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 468 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 469 static DEVICE_ATTR(online, 0644, online_show, online_store);
 470 extern struct device_attribute dev_attr_cmb_enable;
 471 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 472
 473 static struct attribute * subch_attrs[] = {
 474         &dev_attr_chpids.attr,
 475         &dev_attr_pimpampom.attr,
 476         NULL,
 477 };
 478
 479 static struct attribute_group subch_attr_group = {
 480         .attrs = subch_attrs,
 481 };
 482
 483 static inline int
 484 subchannel_add_files (struct device *dev)
 485 {
 486         return sysfs_create_group(&dev->kobj, &subch_attr_group);
 487 }
 488
 489 static struct attribute * ccwdev_attrs[] = {
 490         &dev_attr_devtype.attr,
 491         &dev_attr_cutype.attr,
 492         &dev_attr_modalias.attr,
 493         &dev_attr_online.attr,
 494         &dev_attr_cmb_enable.attr,
 495         &dev_attr_availability.attr,
 496         NULL,
 497 };
 498
 499 static struct attribute_group ccwdev_attr_group = {
 500         .attrs = ccwdev_attrs,
 501 };
 502
 503 static inline int
 504 device_add_files (struct device *dev)
 505 {
 506         return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
 507 }
 508
 509 static inline void
 510 device_remove_files(struct device *dev)
 511 {
 512         sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
 513 }
 514
 515 /* this is a simple abstraction for device_register that sets the
 516  * correct bus type and adds the bus specific files */
 517 int
 518 ccw_device_register(struct ccw_device *cdev)
 519 {
 520         struct device *dev = &cdev->dev;
 521         int ret;
 522
 523         dev->bus = &ccw_bus_type;
 524
 525         if ((ret = device_add(dev)))
 526                 return ret;
 527
 528         set_bit(1, &cdev->private->registered);
 529         if ((ret = device_add_files(dev))) {
 530                 if (test_and_clear_bit(1, &cdev->private->registered))
 531                         device_del(dev);
 532         }
 533         return ret;
 534 }
 535
 536 struct match_data {
 537         unsigned int  devno;
 538         struct ccw_device * sibling;
 539 };
 540
 541 static int
 542 match_devno(struct device * dev, void * data)
 543 {
 544         struct match_data * d = (struct match_data *)data;
 545         struct ccw_device * cdev;
 546
 547         cdev = to_ccwdev(dev);
 548         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
 549             (cdev->private->devno == d->devno) &&
 550             (cdev != d->sibling)) {
 551                 cdev->private->state = DEV_STATE_NOT_OPER;
 552                 return 1;
 553         }
 554         return 0;
 555 }
 556
 557 static struct ccw_device *
 558 get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
 559 {
 560         struct device *dev;
 561         struct match_data data = {
 562                 .devno  = devno,
 563                 .sibling = sibling,
 564         };
 565
 566         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
 567
 568         return dev ? to_ccwdev(dev) : NULL;
 569 }
 570
 571 static void
 572 ccw_device_add_changed(void *data)
 573 {
 574
 575         struct ccw_device *cdev;
 576
 577         cdev = (struct ccw_device *)data;
 578         if (device_add(&cdev->dev)) {
 579                 put_device(&cdev->dev);
 580                 return;
 581         }
 582         set_bit(1, &cdev->private->registered);
 583         if (device_add_files(&cdev->dev)) {
 584                 if (test_and_clear_bit(1, &cdev->private->registered))
 585                         device_unregister(&cdev->dev);
 586         }
 587 }
 588
 589 extern int css_get_ssd_info(struct subchannel *sch);
 590
 591 void
 592 ccw_device_do_unreg_rereg(void *data)
 593 {
 594         struct ccw_device *cdev;
 595         struct subchannel *sch;
 596         int need_rename;
 597
 598         cdev = (struct ccw_device *)data;
 599         sch = to_subchannel(cdev->dev.parent);
 600         if (cdev->private->devno != sch->schib.pmcw.dev) {
 601                 /*
 602                  * The device number has changed. This is usually only when
 603                  * a device has been detached under VM and then re-appeared
 604                  * on another subchannel because of a different attachment
 605                  * order than before. Ideally, we should should just switch
 606                  * subchannels, but unfortunately, this is not possible with
 607                  * the current implementation.
 608                  * Instead, we search for the old subchannel for this device
 609                  * number and deregister so there are no collisions with the
 610                  * newly registered ccw_device.
 611                  * FIXME: Find another solution so the block layer doesn't
 612                  *        get possibly sick...
 613                  */
 614                 struct ccw_device *other_cdev;
 615
 616                 need_rename = 1;
 617                 other_cdev = get_disc_ccwdev_by_devno(sch->schib.pmcw.dev,
 618                                                       cdev);
 619                 if (other_cdev) {
 620                         struct subchannel *other_sch;
 621
 622                         other_sch = to_subchannel(other_cdev->dev.parent);
 623                         if (get_device(&other_sch->dev)) {
 624                                 stsch(other_sch->irq, &other_sch->schib);
 625                                 if (other_sch->schib.pmcw.dnv) {
 626                                         other_sch->schib.pmcw.intparm = 0;
 627                                         cio_modify(other_sch);
 628                                 }
 629                                 device_unregister(&other_sch->dev);
 630                         }
 631                 }
 632                 /* Update ssd info here. */
 633                 css_get_ssd_info(sch);
 634                 cdev->private->devno = sch->schib.pmcw.dev;
 635         } else
 636                 need_rename = 0;
 637         device_remove_files(&cdev->dev);
 638         if (test_and_clear_bit(1, &cdev->private->registered))
 639                 device_del(&cdev->dev);
 640         if (need_rename)
 641                 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
 642                           sch->schib.pmcw.dev);
 643         PREPARE_WORK(&cdev->private->kick_work,
 644                      ccw_device_add_changed, (void *)cdev);
 645         queue_work(ccw_device_work, &cdev->private->kick_work);
 646 }
 647
 648 static void
 649 ccw_device_release(struct device *dev)
 650 {
 651         struct ccw_device *cdev;
 652
 653         cdev = to_ccwdev(dev);
 654         kfree(cdev->private);
 655         kfree(cdev);
 656 }
 657
 658 /*
 659  * Register recognized device.
 660  */
 661 static void
 662 io_subchannel_register(void *data)
 663 {
 664         struct ccw_device *cdev;
 665         struct subchannel *sch;
 666         int ret;
 667         unsigned long flags;
 668
 669         cdev = (struct ccw_device *) data;
 670         sch = to_subchannel(cdev->dev.parent);
 671
 672         if (klist_node_attached(&cdev->dev.knode_parent)) {
 673                 bus_rescan_devices(&ccw_bus_type);
 674                 goto out;
 675         }
 676         /* make it known to the system */
 677         ret = ccw_device_register(cdev);
 678         if (ret) {
 679                 printk (KERN_WARNING "%s: could not register %s\n",
 680                         __func__, cdev->dev.bus_id);
 681                 put_device(&cdev->dev);
 682                 spin_lock_irqsave(&sch->lock, flags);
 683                 sch->dev.driver_data = NULL;
 684                 spin_unlock_irqrestore(&sch->lock, flags);
 685                 kfree (cdev->private);
 686                 kfree (cdev);
 687                 put_device(&sch->dev);
 688                 if (atomic_dec_and_test(&ccw_device_init_count))
 689                         wake_up(&ccw_device_init_wq);
 690                 return;
 691         }
 692
 693         ret = subchannel_add_files(cdev->dev.parent);
 694         if (ret)
 695                 printk(KERN_WARNING "%s: could not add attributes to %s\n",
 696                        __func__, sch->dev.bus_id);
 697         put_device(&cdev->dev);
 698 out:
 699         cdev->private->flags.recog_done = 1;
 700         put_device(&sch->dev);
 701         wake_up(&cdev->private->wait_q);
 702         if (atomic_dec_and_test(&ccw_device_init_count))
 703                 wake_up(&ccw_device_init_wq);
 704 }
 705
 706 void
 707 ccw_device_call_sch_unregister(void *data)
 708 {
 709         struct ccw_device *cdev = data;
 710         struct subchannel *sch;
 711
 712         sch = to_subchannel(cdev->dev.parent);
 713         device_unregister(&sch->dev);
 714         /* Reset intparm to zeroes. */
 715         sch->schib.pmcw.intparm = 0;
 716         cio_modify(sch);
 717         put_device(&cdev->dev);
 718         put_device(&sch->dev);
 719 }
 720
 721 /*
 722  * subchannel recognition done. Called from the state machine.
 723  */
 724 void
 725 io_subchannel_recog_done(struct ccw_device *cdev)
 726 {
 727         struct subchannel *sch;
 728
 729         if (css_init_done == 0) {
 730                 cdev->private->flags.recog_done = 1;
 731                 return;
 732         }
 733         switch (cdev->private->state) {
 734         case DEV_STATE_NOT_OPER:
 735                 cdev->private->flags.recog_done = 1;
 736                 /* Remove device found not operational. */
 737                 if (!get_device(&cdev->dev))
 738                         break;
 739                 sch = to_subchannel(cdev->dev.parent);
 740                 PREPARE_WORK(&cdev->private->kick_work,
 741                              ccw_device_call_sch_unregister, (void *) cdev);
 742                 queue_work(slow_path_wq, &cdev->private->kick_work);
 743                 if (atomic_dec_and_test(&ccw_device_init_count))
 744                         wake_up(&ccw_device_init_wq);
 745                 break;
 746         case DEV_STATE_BOXED:
 747                 /* Device did not respond in time. */
 748         case DEV_STATE_OFFLINE:
 749                 /*
 750                  * We can't register the device in interrupt context so
 751                  * we schedule a work item.
 752                  */
 753                 if (!get_device(&cdev->dev))
 754                         break;
 755                 PREPARE_WORK(&cdev->private->kick_work,
 756                              io_subchannel_register, (void *) cdev);
 757                 queue_work(slow_path_wq, &cdev->private->kick_work);
 758                 break;
 759         }
 760 }
 761
 762 static int
 763 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 764 {
 765         int rc;
 766         struct ccw_device_private *priv;
 767
 768         sch->dev.driver_data = cdev;
 769         sch->driver = &io_subchannel_driver;
 770         cdev->ccwlock = &sch->lock;
 771         /* Init private data. */
 772         priv = cdev->private;
 773         priv->devno = sch->schib.pmcw.dev;
 774         priv->irq = sch->irq;
 775         priv->state = DEV_STATE_NOT_OPER;
 776         INIT_LIST_HEAD(&priv->cmb_list);
 777         init_waitqueue_head(&priv->wait_q);
 778         init_timer(&priv->timer);
 779
 780         /* Set an initial name for the device. */
 781         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
 782                   sch->schib.pmcw.dev);
 783
 784         /* Increase counter of devices currently in recognition. */
 785         atomic_inc(&ccw_device_init_count);
 786
 787         /* Start async. device sensing. */
 788         spin_lock_irq(&sch->lock);
 789         rc = ccw_device_recognition(cdev);
 790         spin_unlock_irq(&sch->lock);
 791         if (rc) {
 792                 if (atomic_dec_and_test(&ccw_device_init_count))
 793                         wake_up(&ccw_device_init_wq);
 794         }
 795         return rc;
 796 }
 797
 798 static int
 799 io_subchannel_probe (struct device *pdev)
 800 {
 801         struct subchannel *sch;
 802         struct ccw_device *cdev;
 803         int rc;
 804         unsigned long flags;
 805
 806         sch = to_subchannel(pdev);
 807         if (sch->dev.driver_data) {
 808                 /*
 809                  * This subchannel already has an associated ccw_device.
 810                  * Register it and exit. This happens for all early
 811                  * device, e.g. the console.
 812                  */
 813                 cdev = sch->dev.driver_data;
 814                 device_initialize(&cdev->dev);
 815                 ccw_device_register(cdev);
 816                 subchannel_add_files(&sch->dev);
 817                 /*
 818                  * Check if the device is already online. If it is
 819                  * the reference count needs to be corrected
 820                  * (see ccw_device_online and css_init_done for the
 821                  * ugly details).
 822                  */
 823                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
 824                     cdev->private->state != DEV_STATE_OFFLINE &&
 825                     cdev->private->state != DEV_STATE_BOXED)
 826                         get_device(&cdev->dev);
 827                 return 0;
 828         }
 829         cdev  = kmalloc (sizeof(*cdev), GFP_KERNEL);
 830         if (!cdev)
 831                 return -ENOMEM;
 832         memset(cdev, 0, sizeof(struct ccw_device));
 833         cdev->private = kmalloc(sizeof(struct ccw_device_private),
 834                                 GFP_KERNEL | GFP_DMA);
 835         if (!cdev->private) {
 836                 kfree(cdev);
 837                 return -ENOMEM;
 838         }
 839         memset(cdev->private, 0, sizeof(struct ccw_device_private));
 840         atomic_set(&cdev->private->onoff, 0);
 841         cdev->dev = (struct device) {
 842                 .parent = pdev,
 843                 .release = ccw_device_release,
 844         };
 845         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
 846         /* Do first half of device_register. */
 847         device_initialize(&cdev->dev);
 848
 849         if (!get_device(&sch->dev)) {
 850                 if (cdev->dev.release)
 851                         cdev->dev.release(&cdev->dev);
 852                 return -ENODEV;
 853         }
 854
 855         rc = io_subchannel_recog(cdev, to_subchannel(pdev));
 856         if (rc) {
 857                 spin_lock_irqsave(&sch->lock, flags);
 858                 sch->dev.driver_data = NULL;
 859                 spin_unlock_irqrestore(&sch->lock, flags);
 860                 if (cdev->dev.release)
 861                         cdev->dev.release(&cdev->dev);
 862         }
 863
 864         return rc;
 865 }
 866
 867 static void
 868 ccw_device_unregister(void *data)
 869 {
 870         struct ccw_device *cdev;
 871
 872         cdev = (struct ccw_device *)data;
 873         if (test_and_clear_bit(1, &cdev->private->registered))
 874                 device_unregister(&cdev->dev);
 875         put_device(&cdev->dev);
 876 }
 877
 878 static int
 879 io_subchannel_remove (struct device *dev)
 880 {
 881         struct ccw_device *cdev;
 882         unsigned long flags;
 883
 884         if (!dev->driver_data)
 885                 return 0;
 886         cdev = dev->driver_data;
 887         /* Set ccw device to not operational and drop reference. */
 888         spin_lock_irqsave(cdev->ccwlock, flags);
 889         dev->driver_data = NULL;
 890         cdev->private->state = DEV_STATE_NOT_OPER;
 891         spin_unlock_irqrestore(cdev->ccwlock, flags);
 892         /*
 893          * Put unregistration on workqueue to avoid livelocks on the css bus
 894          * semaphore.
 895          */
 896         if (get_device(&cdev->dev)) {
 897                 PREPARE_WORK(&cdev->private->kick_work,
 898                              ccw_device_unregister, (void *) cdev);
 899                 queue_work(ccw_device_work, &cdev->private->kick_work);
 900         }
 901         return 0;
 902 }
 903
 904 static int
 905 io_subchannel_notify(struct device *dev, int event)
 906 {
 907         struct ccw_device *cdev;
 908
 909         cdev = dev->driver_data;
 910         if (!cdev)
 911                 return 0;
 912         if (!cdev->drv)
 913                 return 0;
 914         if (!cdev->online)
 915                 return 0;
 916         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
 917 }
 918
 919 static void
 920 io_subchannel_verify(struct device *dev)
 921 {
 922         struct ccw_device *cdev;
 923
 924         cdev = dev->driver_data;
 925         if (cdev)
 926                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
 927 }
 928
 929 static void
 930 io_subchannel_ioterm(struct device *dev)
 931 {
 932         struct ccw_device *cdev;
 933
 934         cdev = dev->driver_data;
 935         if (!cdev)
 936                 return;
 937         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
 938         if (cdev->handler)
 939                 cdev->handler(cdev, cdev->private->intparm,
 940                               ERR_PTR(-EIO));
 941 }
 942
 943 static void
 944 io_subchannel_shutdown(struct device *dev)
 945 {
 946         struct subchannel *sch;
 947         struct ccw_device *cdev;
 948         int ret;
 949
 950         sch = to_subchannel(dev);
 951         cdev = dev->driver_data;
 952
 953         if (cio_is_console(sch->irq))
 954                 return;
 955         if (!sch->schib.pmcw.ena)
 956                 /* Nothing to do. */
 957                 return;
 958         ret = cio_disable_subchannel(sch);
 959         if (ret != -EBUSY)
 960                 /* Subchannel is disabled, we're done. */
 961                 return;
 962         cdev->private->state = DEV_STATE_QUIESCE;
 963         if (cdev->handler)
 964                 cdev->handler(cdev, cdev->private->intparm,
 965                               ERR_PTR(-EIO));
 966         ret = ccw_device_cancel_halt_clear(cdev);
 967         if (ret == -EBUSY) {
 968                 ccw_device_set_timeout(cdev, HZ/10);
 969                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 970         }
 971         cio_disable_subchannel(sch);
 972 }
 973
 974 #ifdef CONFIG_CCW_CONSOLE
 975 static struct ccw_device console_cdev;
 976 static struct ccw_device_private console_private;
 977 static int console_cdev_in_use;
 978
 979 static int
 980 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
 981 {
 982         int rc;
 983
 984         /* Initialize the ccw_device structure. */
 985         cdev->dev = (struct device) {
 986                 .parent = &sch->dev,
 987         };
 988         /* Initialize the subchannel structure */
 989         sch->dev.parent = &css_bus_device;
 990         sch->dev.bus = &css_bus_type;
 991
 992         rc = io_subchannel_recog(cdev, sch);
 993         if (rc)
 994                 return rc;
 995
 996         /* Now wait for the async. recognition to come to an end. */
 997         spin_lock_irq(cdev->ccwlock);
 998         while (!dev_fsm_final_state(cdev))
 999                 wait_cons_dev();
1000         rc = -EIO;
1001         if (cdev->private->state != DEV_STATE_OFFLINE)
1002                 goto out_unlock;
1003         ccw_device_online(cdev);
1004         while (!dev_fsm_final_state(cdev))
1005                 wait_cons_dev();
1006         if (cdev->private->state != DEV_STATE_ONLINE)
1007                 goto out_unlock;
1008         rc = 0;
1009 out_unlock:
1010         spin_unlock_irq(cdev->ccwlock);
1011         return 0;
1012 }
1013
1014 struct ccw_device *
1015 ccw_device_probe_console(void)
1016 {
1017         struct subchannel *sch;
1018         int ret;
1019
1020         if (xchg(&console_cdev_in_use, 1) != 0)
1021                 return NULL;
1022         sch = cio_probe_console();
1023         if (IS_ERR(sch)) {
1024                 console_cdev_in_use = 0;
1025                 return (void *) sch;
1026         }
1027         memset(&console_cdev, 0, sizeof(struct ccw_device));
1028         memset(&console_private, 0, sizeof(struct ccw_device_private));
1029         console_cdev.private = &console_private;
1030         ret = ccw_device_console_enable(&console_cdev, sch);
1031         if (ret) {
1032                 cio_release_console();
1033                 console_cdev_in_use = 0;
1034                 return ERR_PTR(ret);
1035         }
1036         console_cdev.online = 1;
1037         return &console_cdev;
1038 }
1039 #endif
1040
1041 /*
1042  * get ccw_device matching the busid, but only if owned by cdrv
1043  */
1044 static int
1045 __ccwdev_check_busid(struct device *dev, void *id)
1046 {
1047         char *bus_id;
1048
1049         bus_id = (char *)id;
1050
1051         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1052 }
1053
1054
1055 struct ccw_device *
1056 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1057 {
1058         struct device *dev;
1059         struct device_driver *drv;
1060
1061         drv = get_driver(&cdrv->driver);
1062         if (!drv)
1063                 return NULL;
1064
1065         dev = driver_find_device(drv, NULL, (void *)bus_id,
1066                                  __ccwdev_check_busid);
1067         put_driver(drv);
1068
1069         return dev ? to_ccwdev(dev) : 0;
1070 }
1071
1072 /************************** device driver handling ************************/
1073
1074 /* This is the implementation of the ccw_driver class. The probe, remove
1075  * and release methods are initially very similar to the device_driver
1076  * implementations, with the difference that they have ccw_device
1077  * arguments.
1078  *
1079  * A ccw driver also contains the information that is needed for
1080  * device matching.
1081  */
1082 static int
1083 ccw_device_probe (struct device *dev)
1084 {
1085         struct ccw_device *cdev = to_ccwdev(dev);
1086         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1087         int ret;
1088
1089         cdev->drv = cdrv; /* to let the driver call _set_online */
1090
1091         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1092
1093         if (ret) {
1094                 cdev->drv = 0;
1095                 return ret;
1096         }
1097
1098         return 0;
1099 }
1100
1101 static int
1102 ccw_device_remove (struct device *dev)
1103 {
1104         struct ccw_device *cdev = to_ccwdev(dev);
1105         struct ccw_driver *cdrv = cdev->drv;
1106         int ret;
1107
1108         pr_debug("removing device %s\n", cdev->dev.bus_id);
1109         if (cdrv->remove)
1110                 cdrv->remove(cdev);
1111         if (cdev->online) {
1112                 cdev->online = 0;
1113                 spin_lock_irq(cdev->ccwlock);
1114                 ret = ccw_device_offline(cdev);
1115                 spin_unlock_irq(cdev->ccwlock);
1116                 if (ret == 0)
1117                         wait_event(cdev->private->wait_q,
1118                                    dev_fsm_final_state(cdev));
1119                 else
1120                         //FIXME: we can't fail!
1121                         pr_debug("ccw_device_offline returned %d, device %s\n",
1122                                  ret, cdev->dev.bus_id);
1123         }
1124         ccw_device_set_timeout(cdev, 0);
1125         cdev->drv = 0;
1126         return 0;
1127 }
1128
1129 int
1130 ccw_driver_register (struct ccw_driver *cdriver)
1131 {
1132         struct device_driver *drv = &cdriver->driver;
1133
1134         drv->bus = &ccw_bus_type;
1135         drv->name = cdriver->name;
1136         drv->probe = ccw_device_probe;
1137         drv->remove = ccw_device_remove;
1138
1139         return driver_register(drv);
1140 }
1141
1142 void
1143 ccw_driver_unregister (struct ccw_driver *cdriver)
1144 {
1145         driver_unregister(&cdriver->driver);
1146 }
1147
1148 MODULE_LICENSE("GPL");
1149 EXPORT_SYMBOL(ccw_device_set_online);
1150 EXPORT_SYMBOL(ccw_device_set_offline);
1151 EXPORT_SYMBOL(ccw_driver_register);
1152 EXPORT_SYMBOL(ccw_driver_unregister);
1153 EXPORT_SYMBOL(get_ccwdev_by_busid);
1154 EXPORT_SYMBOL(ccw_bus_type);
1155 EXPORT_SYMBOL(ccw_device_work);
1156 EXPORT_SYMBOL(ccw_device_notify_work);