Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...
[linux-2.6] / drivers / s390 / cio / device.c
1 /*
2  *  drivers/s390/cio/device.c
3  *  bus driver for ccw devices
4  *
5  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
6  *                       IBM Corporation
7  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
9  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
10  */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/spinlock.h>
14 #include <linux/errno.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/list.h>
18 #include <linux/device.h>
19 #include <linux/workqueue.h>
20
21 #include <asm/ccwdev.h>
22 #include <asm/cio.h>
23 #include <asm/param.h>          /* HZ */
24
25 #include "cio.h"
26 #include "cio_debug.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 /* Store modalias string delimited by prefix/suffix string into buffer with
57  * specified size. Return length of resulting string (excluding trailing '\0')
58  * even if string doesn't fit buffer (snprintf semantics). */
59 static int snprint_alias(char *buf, size_t size,
60                          struct ccw_device_id *id, const char *suffix)
61 {
62         int len;
63
64         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
65         if (len > size)
66                 return len;
67         buf += len;
68         size -= len;
69
70         if (id->dev_type != 0)
71                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
72                                 id->dev_model, suffix);
73         else
74                 len += snprintf(buf, size, "dtdm%s", suffix);
75
76         return len;
77 }
78
79 /* Set up environment variables for ccw device uevent. Return 0 on success,
80  * non-zero otherwise. */
81 static int ccw_uevent(struct device *dev, char **envp, int num_envp,
82                       char *buffer, int buffer_size)
83 {
84         struct ccw_device *cdev = to_ccwdev(dev);
85         struct ccw_device_id *id = &(cdev->id);
86         int i = 0;
87         int len = 0;
88         int ret;
89         char modalias_buf[30];
90
91         /* CU_TYPE= */
92         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
93                              "CU_TYPE=%04X", id->cu_type);
94         if (ret)
95                 return ret;
96
97         /* CU_MODEL= */
98         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
99                              "CU_MODEL=%02X", id->cu_model);
100         if (ret)
101                 return ret;
102
103         /* The next two can be zero, that's ok for us */
104         /* DEV_TYPE= */
105         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
106                              "DEV_TYPE=%04X", id->dev_type);
107         if (ret)
108                 return ret;
109
110         /* DEV_MODEL= */
111         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
112                              "DEV_MODEL=%02X", id->dev_model);
113         if (ret)
114                 return ret;
115
116         /* MODALIAS=  */
117         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
118         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
119                              "MODALIAS=%s", modalias_buf);
120         return ret;
121 }
122
123 struct bus_type ccw_bus_type;
124
125 static int io_subchannel_probe (struct subchannel *);
126 static int io_subchannel_remove (struct subchannel *);
127 static int io_subchannel_notify(struct device *, int);
128 static void io_subchannel_verify(struct device *);
129 static void io_subchannel_ioterm(struct device *);
130 static void io_subchannel_shutdown(struct subchannel *);
131
132 static struct css_driver io_subchannel_driver = {
133         .subchannel_type = SUBCHANNEL_TYPE_IO,
134         .drv = {
135                 .name = "io_subchannel",
136                 .bus  = &css_bus_type,
137         },
138         .irq = io_subchannel_irq,
139         .notify = io_subchannel_notify,
140         .verify = io_subchannel_verify,
141         .termination = io_subchannel_ioterm,
142         .probe = io_subchannel_probe,
143         .remove = io_subchannel_remove,
144         .shutdown = io_subchannel_shutdown,
145 };
146
147 struct workqueue_struct *ccw_device_work;
148 struct workqueue_struct *ccw_device_notify_work;
149 wait_queue_head_t ccw_device_init_wq;
150 atomic_t ccw_device_init_count;
151
152 static int __init
153 init_ccw_bus_type (void)
154 {
155         int ret;
156
157         init_waitqueue_head(&ccw_device_init_wq);
158         atomic_set(&ccw_device_init_count, 0);
159
160         ccw_device_work = create_singlethread_workqueue("cio");
161         if (!ccw_device_work)
162                 return -ENOMEM; /* FIXME: better errno ? */
163         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
164         if (!ccw_device_notify_work) {
165                 ret = -ENOMEM; /* FIXME: better errno ? */
166                 goto out_err;
167         }
168         slow_path_wq = create_singlethread_workqueue("kslowcrw");
169         if (!slow_path_wq) {
170                 ret = -ENOMEM; /* FIXME: better errno ? */
171                 goto out_err;
172         }
173         if ((ret = bus_register (&ccw_bus_type)))
174                 goto out_err;
175
176         if ((ret = driver_register(&io_subchannel_driver.drv)))
177                 goto out_err;
178
179         wait_event(ccw_device_init_wq,
180                    atomic_read(&ccw_device_init_count) == 0);
181         flush_workqueue(ccw_device_work);
182         return 0;
183 out_err:
184         if (ccw_device_work)
185                 destroy_workqueue(ccw_device_work);
186         if (ccw_device_notify_work)
187                 destroy_workqueue(ccw_device_notify_work);
188         if (slow_path_wq)
189                 destroy_workqueue(slow_path_wq);
190         return ret;
191 }
192
193 static void __exit
194 cleanup_ccw_bus_type (void)
195 {
196         driver_unregister(&io_subchannel_driver.drv);
197         bus_unregister(&ccw_bus_type);
198         destroy_workqueue(ccw_device_notify_work);
199         destroy_workqueue(ccw_device_work);
200 }
201
202 subsys_initcall(init_ccw_bus_type);
203 module_exit(cleanup_ccw_bus_type);
204
205 /************************ device handling **************************/
206
207 /*
208  * A ccw_device has some interfaces in sysfs in addition to the
209  * standard ones.
210  * The following entries are designed to export the information which
211  * resided in 2.4 in /proc/subchannels. Subchannel and device number
212  * are obvious, so they don't have an entry :)
213  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
214  */
215 static ssize_t
216 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
217 {
218         struct subchannel *sch = to_subchannel(dev);
219         struct chsc_ssd_info *ssd = &sch->ssd_info;
220         ssize_t ret = 0;
221         int chp;
222         int mask;
223
224         for (chp = 0; chp < 8; chp++) {
225                 mask = 0x80 >> chp;
226                 if (ssd->path_mask & mask)
227                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
228                 else
229                         ret += sprintf(buf + ret, "00 ");
230         }
231         ret += sprintf (buf+ret, "\n");
232         return min((ssize_t)PAGE_SIZE, ret);
233 }
234
235 static ssize_t
236 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
237 {
238         struct subchannel *sch = to_subchannel(dev);
239         struct pmcw *pmcw = &sch->schib.pmcw;
240
241         return sprintf (buf, "%02x %02x %02x\n",
242                         pmcw->pim, pmcw->pam, pmcw->pom);
243 }
244
245 static ssize_t
246 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
247 {
248         struct ccw_device *cdev = to_ccwdev(dev);
249         struct ccw_device_id *id = &(cdev->id);
250
251         if (id->dev_type != 0)
252                 return sprintf(buf, "%04x/%02x\n",
253                                 id->dev_type, id->dev_model);
254         else
255                 return sprintf(buf, "n/a\n");
256 }
257
258 static ssize_t
259 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
260 {
261         struct ccw_device *cdev = to_ccwdev(dev);
262         struct ccw_device_id *id = &(cdev->id);
263
264         return sprintf(buf, "%04x/%02x\n",
265                        id->cu_type, id->cu_model);
266 }
267
268 static ssize_t
269 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
270 {
271         struct ccw_device *cdev = to_ccwdev(dev);
272         struct ccw_device_id *id = &(cdev->id);
273         int len;
274
275         len = snprint_alias(buf, PAGE_SIZE, id, "\n") + 1;
276
277         return len > PAGE_SIZE ? PAGE_SIZE : len;
278 }
279
280 static ssize_t
281 online_show (struct device *dev, struct device_attribute *attr, char *buf)
282 {
283         struct ccw_device *cdev = to_ccwdev(dev);
284
285         return sprintf(buf, cdev->online ? "1\n" : "0\n");
286 }
287
288 int ccw_device_is_orphan(struct ccw_device *cdev)
289 {
290         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
291 }
292
293 static void ccw_device_unregister(struct ccw_device *cdev)
294 {
295         if (test_and_clear_bit(1, &cdev->private->registered))
296                 device_del(&cdev->dev);
297 }
298
299 static void ccw_device_remove_orphan_cb(struct device *dev)
300 {
301         struct ccw_device *cdev = to_ccwdev(dev);
302
303         ccw_device_unregister(cdev);
304         put_device(&cdev->dev);
305 }
306
307 static void ccw_device_remove_sch_cb(struct device *dev)
308 {
309         struct subchannel *sch;
310
311         sch = to_subchannel(dev);
312         css_sch_device_unregister(sch);
313         /* Reset intparm to zeroes. */
314         sch->schib.pmcw.intparm = 0;
315         cio_modify(sch);
316         put_device(&sch->dev);
317 }
318
319 static void
320 ccw_device_remove_disconnected(struct ccw_device *cdev)
321 {
322         unsigned long flags;
323         int rc;
324
325         /*
326          * Forced offline in disconnected state means
327          * 'throw away device'.
328          */
329         if (ccw_device_is_orphan(cdev)) {
330                 /*
331                  * Deregister ccw device.
332                  * Unfortunately, we cannot do this directly from the
333                  * attribute method.
334                  */
335                 spin_lock_irqsave(cdev->ccwlock, flags);
336                 cdev->private->state = DEV_STATE_NOT_OPER;
337                 spin_unlock_irqrestore(cdev->ccwlock, flags);
338                 rc = device_schedule_callback(&cdev->dev,
339                                               ccw_device_remove_orphan_cb);
340                 if (rc)
341                         dev_info(&cdev->dev, "Couldn't unregister orphan\n");
342                 return;
343         }
344         /* Deregister subchannel, which will kill the ccw device. */
345         rc = device_schedule_callback(cdev->dev.parent,
346                                       ccw_device_remove_sch_cb);
347         if (rc)
348                 dev_info(&cdev->dev,
349                          "Couldn't unregister disconnected device\n");
350 }
351
352 int
353 ccw_device_set_offline(struct ccw_device *cdev)
354 {
355         int ret;
356
357         if (!cdev)
358                 return -ENODEV;
359         if (!cdev->online || !cdev->drv)
360                 return -EINVAL;
361
362         if (cdev->drv->set_offline) {
363                 ret = cdev->drv->set_offline(cdev);
364                 if (ret != 0)
365                         return ret;
366         }
367         cdev->online = 0;
368         spin_lock_irq(cdev->ccwlock);
369         ret = ccw_device_offline(cdev);
370         if (ret == -ENODEV) {
371                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
372                         cdev->private->state = DEV_STATE_OFFLINE;
373                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
374                 }
375                 spin_unlock_irq(cdev->ccwlock);
376                 return ret;
377         }
378         spin_unlock_irq(cdev->ccwlock);
379         if (ret == 0)
380                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
381         else {
382                 pr_debug("ccw_device_offline returned %d, device %s\n",
383                          ret, cdev->dev.bus_id);
384                 cdev->online = 1;
385         }
386         return ret;
387 }
388
389 int
390 ccw_device_set_online(struct ccw_device *cdev)
391 {
392         int ret;
393
394         if (!cdev)
395                 return -ENODEV;
396         if (cdev->online || !cdev->drv)
397                 return -EINVAL;
398
399         spin_lock_irq(cdev->ccwlock);
400         ret = ccw_device_online(cdev);
401         spin_unlock_irq(cdev->ccwlock);
402         if (ret == 0)
403                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
404         else {
405                 pr_debug("ccw_device_online returned %d, device %s\n",
406                          ret, cdev->dev.bus_id);
407                 return ret;
408         }
409         if (cdev->private->state != DEV_STATE_ONLINE)
410                 return -ENODEV;
411         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
412                 cdev->online = 1;
413                 return 0;
414         }
415         spin_lock_irq(cdev->ccwlock);
416         ret = ccw_device_offline(cdev);
417         spin_unlock_irq(cdev->ccwlock);
418         if (ret == 0)
419                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
420         else 
421                 pr_debug("ccw_device_offline returned %d, device %s\n",
422                          ret, cdev->dev.bus_id);
423         return (ret == 0) ? -ENODEV : ret;
424 }
425
426 static void online_store_handle_offline(struct ccw_device *cdev)
427 {
428         if (cdev->private->state == DEV_STATE_DISCONNECTED)
429                 ccw_device_remove_disconnected(cdev);
430         else if (cdev->drv && cdev->drv->set_offline)
431                 ccw_device_set_offline(cdev);
432 }
433
434 static int online_store_recog_and_online(struct ccw_device *cdev)
435 {
436         int ret;
437
438         /* Do device recognition, if needed. */
439         if (cdev->id.cu_type == 0) {
440                 ret = ccw_device_recognition(cdev);
441                 if (ret) {
442                         printk(KERN_WARNING"Couldn't start recognition "
443                                "for device %s (ret=%d)\n",
444                                cdev->dev.bus_id, ret);
445                         return ret;
446                 }
447                 wait_event(cdev->private->wait_q,
448                            cdev->private->flags.recog_done);
449         }
450         if (cdev->drv && cdev->drv->set_online)
451                 ccw_device_set_online(cdev);
452         return 0;
453 }
454 static void online_store_handle_online(struct ccw_device *cdev, int force)
455 {
456         int ret;
457
458         ret = online_store_recog_and_online(cdev);
459         if (ret)
460                 return;
461         if (force && cdev->private->state == DEV_STATE_BOXED) {
462                 ret = ccw_device_stlck(cdev);
463                 if (ret) {
464                         printk(KERN_WARNING"ccw_device_stlck for device %s "
465                                "returned %d!\n", cdev->dev.bus_id, ret);
466                         return;
467                 }
468                 if (cdev->id.cu_type == 0)
469                         cdev->private->state = DEV_STATE_NOT_OPER;
470                 online_store_recog_and_online(cdev);
471         }
472
473 }
474
475 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
476                              const char *buf, size_t count)
477 {
478         struct ccw_device *cdev = to_ccwdev(dev);
479         int i, force;
480         char *tmp;
481
482         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
483                 return -EAGAIN;
484
485         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
486                 atomic_set(&cdev->private->onoff, 0);
487                 return -EINVAL;
488         }
489         if (!strncmp(buf, "force\n", count)) {
490                 force = 1;
491                 i = 1;
492         } else {
493                 force = 0;
494                 i = simple_strtoul(buf, &tmp, 16);
495         }
496
497         switch (i) {
498         case 0:
499                 online_store_handle_offline(cdev);
500                 break;
501         case 1:
502                 online_store_handle_online(cdev, force);
503                 break;
504         default:
505                 count = -EINVAL;
506         }
507         if (cdev->drv)
508                 module_put(cdev->drv->owner);
509         atomic_set(&cdev->private->onoff, 0);
510         return count;
511 }
512
513 static ssize_t
514 available_show (struct device *dev, struct device_attribute *attr, char *buf)
515 {
516         struct ccw_device *cdev = to_ccwdev(dev);
517         struct subchannel *sch;
518
519         if (ccw_device_is_orphan(cdev))
520                 return sprintf(buf, "no device\n");
521         switch (cdev->private->state) {
522         case DEV_STATE_BOXED:
523                 return sprintf(buf, "boxed\n");
524         case DEV_STATE_DISCONNECTED:
525         case DEV_STATE_DISCONNECTED_SENSE_ID:
526         case DEV_STATE_NOT_OPER:
527                 sch = to_subchannel(dev->parent);
528                 if (!sch->lpm)
529                         return sprintf(buf, "no path\n");
530                 else
531                         return sprintf(buf, "no device\n");
532         default:
533                 /* All other states considered fine. */
534                 return sprintf(buf, "good\n");
535         }
536 }
537
538 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
539 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
540 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
541 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
542 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
543 static DEVICE_ATTR(online, 0644, online_show, online_store);
544 extern struct device_attribute dev_attr_cmb_enable;
545 static DEVICE_ATTR(availability, 0444, available_show, NULL);
546
547 static struct attribute * subch_attrs[] = {
548         &dev_attr_chpids.attr,
549         &dev_attr_pimpampom.attr,
550         NULL,
551 };
552
553 static struct attribute_group subch_attr_group = {
554         .attrs = subch_attrs,
555 };
556
557 struct attribute_group *subch_attr_groups[] = {
558         &subch_attr_group,
559         NULL,
560 };
561
562 static struct attribute * ccwdev_attrs[] = {
563         &dev_attr_devtype.attr,
564         &dev_attr_cutype.attr,
565         &dev_attr_modalias.attr,
566         &dev_attr_online.attr,
567         &dev_attr_cmb_enable.attr,
568         &dev_attr_availability.attr,
569         NULL,
570 };
571
572 static struct attribute_group ccwdev_attr_group = {
573         .attrs = ccwdev_attrs,
574 };
575
576 static struct attribute_group *ccwdev_attr_groups[] = {
577         &ccwdev_attr_group,
578         NULL,
579 };
580
581 /* this is a simple abstraction for device_register that sets the
582  * correct bus type and adds the bus specific files */
583 static int ccw_device_register(struct ccw_device *cdev)
584 {
585         struct device *dev = &cdev->dev;
586         int ret;
587
588         dev->bus = &ccw_bus_type;
589
590         if ((ret = device_add(dev)))
591                 return ret;
592
593         set_bit(1, &cdev->private->registered);
594         return ret;
595 }
596
597 struct match_data {
598         struct ccw_dev_id dev_id;
599         struct ccw_device * sibling;
600 };
601
602 static int
603 match_devno(struct device * dev, void * data)
604 {
605         struct match_data * d = data;
606         struct ccw_device * cdev;
607
608         cdev = to_ccwdev(dev);
609         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
610             !ccw_device_is_orphan(cdev) &&
611             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
612             (cdev != d->sibling))
613                 return 1;
614         return 0;
615 }
616
617 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
618                                                      struct ccw_device *sibling)
619 {
620         struct device *dev;
621         struct match_data data;
622
623         data.dev_id = *dev_id;
624         data.sibling = sibling;
625         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
626
627         return dev ? to_ccwdev(dev) : NULL;
628 }
629
630 static int match_orphan(struct device *dev, void *data)
631 {
632         struct ccw_dev_id *dev_id;
633         struct ccw_device *cdev;
634
635         dev_id = data;
636         cdev = to_ccwdev(dev);
637         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
638 }
639
640 static struct ccw_device *
641 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
642                               struct ccw_dev_id *dev_id)
643 {
644         struct device *dev;
645
646         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
647                                 match_orphan);
648
649         return dev ? to_ccwdev(dev) : NULL;
650 }
651
652 static void
653 ccw_device_add_changed(struct work_struct *work)
654 {
655         struct ccw_device_private *priv;
656         struct ccw_device *cdev;
657
658         priv = container_of(work, struct ccw_device_private, kick_work);
659         cdev = priv->cdev;
660         if (device_add(&cdev->dev)) {
661                 put_device(&cdev->dev);
662                 return;
663         }
664         set_bit(1, &cdev->private->registered);
665 }
666
667 void ccw_device_do_unreg_rereg(struct work_struct *work)
668 {
669         struct ccw_device_private *priv;
670         struct ccw_device *cdev;
671         struct subchannel *sch;
672
673         priv = container_of(work, struct ccw_device_private, kick_work);
674         cdev = priv->cdev;
675         sch = to_subchannel(cdev->dev.parent);
676
677         ccw_device_unregister(cdev);
678         PREPARE_WORK(&cdev->private->kick_work,
679                      ccw_device_add_changed);
680         queue_work(ccw_device_work, &cdev->private->kick_work);
681 }
682
683 static void
684 ccw_device_release(struct device *dev)
685 {
686         struct ccw_device *cdev;
687
688         cdev = to_ccwdev(dev);
689         kfree(cdev->private);
690         kfree(cdev);
691 }
692
693 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
694 {
695         struct ccw_device *cdev;
696
697         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
698         if (cdev) {
699                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
700                                         GFP_KERNEL | GFP_DMA);
701                 if (cdev->private)
702                         return cdev;
703         }
704         kfree(cdev);
705         return ERR_PTR(-ENOMEM);
706 }
707
708 static int io_subchannel_initialize_dev(struct subchannel *sch,
709                                         struct ccw_device *cdev)
710 {
711         cdev->private->cdev = cdev;
712         atomic_set(&cdev->private->onoff, 0);
713         cdev->dev.parent = &sch->dev;
714         cdev->dev.release = ccw_device_release;
715         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
716         cdev->dev.groups = ccwdev_attr_groups;
717         /* Do first half of device_register. */
718         device_initialize(&cdev->dev);
719         if (!get_device(&sch->dev)) {
720                 if (cdev->dev.release)
721                         cdev->dev.release(&cdev->dev);
722                 return -ENODEV;
723         }
724         return 0;
725 }
726
727 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
728 {
729         struct ccw_device *cdev;
730         int ret;
731
732         cdev = io_subchannel_allocate_dev(sch);
733         if (!IS_ERR(cdev)) {
734                 ret = io_subchannel_initialize_dev(sch, cdev);
735                 if (ret) {
736                         kfree(cdev);
737                         cdev = ERR_PTR(ret);
738                 }
739         }
740         return cdev;
741 }
742
743 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
744
745 static void sch_attach_device(struct subchannel *sch,
746                               struct ccw_device *cdev)
747 {
748         css_update_ssd_info(sch);
749         spin_lock_irq(sch->lock);
750         sch->dev.driver_data = cdev;
751         cdev->private->schid = sch->schid;
752         cdev->ccwlock = sch->lock;
753         device_trigger_reprobe(sch);
754         spin_unlock_irq(sch->lock);
755 }
756
757 static void sch_attach_disconnected_device(struct subchannel *sch,
758                                            struct ccw_device *cdev)
759 {
760         struct subchannel *other_sch;
761         int ret;
762
763         other_sch = to_subchannel(get_device(cdev->dev.parent));
764         ret = device_move(&cdev->dev, &sch->dev);
765         if (ret) {
766                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
767                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
768                               cdev->private->dev_id.devno, ret);
769                 put_device(&other_sch->dev);
770                 return;
771         }
772         other_sch->dev.driver_data = NULL;
773         /* No need to keep a subchannel without ccw device around. */
774         css_sch_device_unregister(other_sch);
775         put_device(&other_sch->dev);
776         sch_attach_device(sch, cdev);
777 }
778
779 static void sch_attach_orphaned_device(struct subchannel *sch,
780                                        struct ccw_device *cdev)
781 {
782         int ret;
783
784         /* Try to move the ccw device to its new subchannel. */
785         ret = device_move(&cdev->dev, &sch->dev);
786         if (ret) {
787                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
788                               "failed (ret=%d)!\n",
789                               cdev->private->dev_id.ssid,
790                               cdev->private->dev_id.devno, ret);
791                 return;
792         }
793         sch_attach_device(sch, cdev);
794 }
795
796 static void sch_create_and_recog_new_device(struct subchannel *sch)
797 {
798         struct ccw_device *cdev;
799
800         /* Need to allocate a new ccw device. */
801         cdev = io_subchannel_create_ccwdev(sch);
802         if (IS_ERR(cdev)) {
803                 /* OK, we did everything we could... */
804                 css_sch_device_unregister(sch);
805                 return;
806         }
807         spin_lock_irq(sch->lock);
808         sch->dev.driver_data = cdev;
809         spin_unlock_irq(sch->lock);
810         /* Start recognition for the new ccw device. */
811         if (io_subchannel_recog(cdev, sch)) {
812                 spin_lock_irq(sch->lock);
813                 sch->dev.driver_data = NULL;
814                 spin_unlock_irq(sch->lock);
815                 if (cdev->dev.release)
816                         cdev->dev.release(&cdev->dev);
817                 css_sch_device_unregister(sch);
818         }
819 }
820
821
822 void ccw_device_move_to_orphanage(struct work_struct *work)
823 {
824         struct ccw_device_private *priv;
825         struct ccw_device *cdev;
826         struct ccw_device *replacing_cdev;
827         struct subchannel *sch;
828         int ret;
829         struct channel_subsystem *css;
830         struct ccw_dev_id dev_id;
831
832         priv = container_of(work, struct ccw_device_private, kick_work);
833         cdev = priv->cdev;
834         sch = to_subchannel(cdev->dev.parent);
835         css = to_css(sch->dev.parent);
836         dev_id.devno = sch->schib.pmcw.dev;
837         dev_id.ssid = sch->schid.ssid;
838
839         /*
840          * Move the orphaned ccw device to the orphanage so the replacing
841          * ccw device can take its place on the subchannel.
842          */
843         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
844         if (ret) {
845                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
846                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
847                               cdev->private->dev_id.devno, ret);
848                 return;
849         }
850         cdev->ccwlock = css->pseudo_subchannel->lock;
851         /*
852          * Search for the replacing ccw device
853          * - among the disconnected devices
854          * - in the orphanage
855          */
856         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
857         if (replacing_cdev) {
858                 sch_attach_disconnected_device(sch, replacing_cdev);
859                 return;
860         }
861         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
862         if (replacing_cdev) {
863                 sch_attach_orphaned_device(sch, replacing_cdev);
864                 return;
865         }
866         sch_create_and_recog_new_device(sch);
867 }
868
869 /*
870  * Register recognized device.
871  */
872 static void
873 io_subchannel_register(struct work_struct *work)
874 {
875         struct ccw_device_private *priv;
876         struct ccw_device *cdev;
877         struct subchannel *sch;
878         int ret;
879         unsigned long flags;
880
881         priv = container_of(work, struct ccw_device_private, kick_work);
882         cdev = priv->cdev;
883         sch = to_subchannel(cdev->dev.parent);
884         css_update_ssd_info(sch);
885         /*
886          * io_subchannel_register() will also be called after device
887          * recognition has been done for a boxed device (which will already
888          * be registered). We need to reprobe since we may now have sense id
889          * information.
890          */
891         if (klist_node_attached(&cdev->dev.knode_parent)) {
892                 if (!cdev->drv) {
893                         ret = device_reprobe(&cdev->dev);
894                         if (ret)
895                                 /* We can't do much here. */
896                                 dev_info(&cdev->dev, "device_reprobe() returned"
897                                          " %d\n", ret);
898                 }
899                 goto out;
900         }
901         /*
902          * Now we know this subchannel will stay, we can throw
903          * our delayed uevent.
904          */
905         sch->dev.uevent_suppress = 0;
906         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
907         /* make it known to the system */
908         ret = ccw_device_register(cdev);
909         if (ret) {
910                 printk (KERN_WARNING "%s: could not register %s\n",
911                         __func__, cdev->dev.bus_id);
912                 put_device(&cdev->dev);
913                 spin_lock_irqsave(sch->lock, flags);
914                 sch->dev.driver_data = NULL;
915                 spin_unlock_irqrestore(sch->lock, flags);
916                 kfree (cdev->private);
917                 kfree (cdev);
918                 put_device(&sch->dev);
919                 if (atomic_dec_and_test(&ccw_device_init_count))
920                         wake_up(&ccw_device_init_wq);
921                 return;
922         }
923         put_device(&cdev->dev);
924 out:
925         cdev->private->flags.recog_done = 1;
926         put_device(&sch->dev);
927         wake_up(&cdev->private->wait_q);
928         if (atomic_dec_and_test(&ccw_device_init_count))
929                 wake_up(&ccw_device_init_wq);
930 }
931
932 void
933 ccw_device_call_sch_unregister(struct work_struct *work)
934 {
935         struct ccw_device_private *priv;
936         struct ccw_device *cdev;
937         struct subchannel *sch;
938
939         priv = container_of(work, struct ccw_device_private, kick_work);
940         cdev = priv->cdev;
941         sch = to_subchannel(cdev->dev.parent);
942         css_sch_device_unregister(sch);
943         /* Reset intparm to zeroes. */
944         sch->schib.pmcw.intparm = 0;
945         cio_modify(sch);
946         put_device(&cdev->dev);
947         put_device(&sch->dev);
948 }
949
950 /*
951  * subchannel recognition done. Called from the state machine.
952  */
953 void
954 io_subchannel_recog_done(struct ccw_device *cdev)
955 {
956         struct subchannel *sch;
957
958         if (css_init_done == 0) {
959                 cdev->private->flags.recog_done = 1;
960                 return;
961         }
962         switch (cdev->private->state) {
963         case DEV_STATE_NOT_OPER:
964                 cdev->private->flags.recog_done = 1;
965                 /* Remove device found not operational. */
966                 if (!get_device(&cdev->dev))
967                         break;
968                 sch = to_subchannel(cdev->dev.parent);
969                 PREPARE_WORK(&cdev->private->kick_work,
970                              ccw_device_call_sch_unregister);
971                 queue_work(slow_path_wq, &cdev->private->kick_work);
972                 if (atomic_dec_and_test(&ccw_device_init_count))
973                         wake_up(&ccw_device_init_wq);
974                 break;
975         case DEV_STATE_BOXED:
976                 /* Device did not respond in time. */
977         case DEV_STATE_OFFLINE:
978                 /* 
979                  * We can't register the device in interrupt context so
980                  * we schedule a work item.
981                  */
982                 if (!get_device(&cdev->dev))
983                         break;
984                 PREPARE_WORK(&cdev->private->kick_work,
985                              io_subchannel_register);
986                 queue_work(slow_path_wq, &cdev->private->kick_work);
987                 break;
988         }
989 }
990
991 static int
992 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
993 {
994         int rc;
995         struct ccw_device_private *priv;
996
997         sch->dev.driver_data = cdev;
998         sch->driver = &io_subchannel_driver;
999         cdev->ccwlock = sch->lock;
1000
1001         /* Init private data. */
1002         priv = cdev->private;
1003         priv->dev_id.devno = sch->schib.pmcw.dev;
1004         priv->dev_id.ssid = sch->schid.ssid;
1005         priv->schid = sch->schid;
1006         priv->state = DEV_STATE_NOT_OPER;
1007         INIT_LIST_HEAD(&priv->cmb_list);
1008         init_waitqueue_head(&priv->wait_q);
1009         init_timer(&priv->timer);
1010
1011         /* Set an initial name for the device. */
1012         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1013                   sch->schid.ssid, sch->schib.pmcw.dev);
1014
1015         /* Increase counter of devices currently in recognition. */
1016         atomic_inc(&ccw_device_init_count);
1017
1018         /* Start async. device sensing. */
1019         spin_lock_irq(sch->lock);
1020         rc = ccw_device_recognition(cdev);
1021         spin_unlock_irq(sch->lock);
1022         if (rc) {
1023                 if (atomic_dec_and_test(&ccw_device_init_count))
1024                         wake_up(&ccw_device_init_wq);
1025         }
1026         return rc;
1027 }
1028
1029 static void ccw_device_move_to_sch(struct work_struct *work)
1030 {
1031         struct ccw_device_private *priv;
1032         int rc;
1033         struct subchannel *sch;
1034         struct ccw_device *cdev;
1035         struct subchannel *former_parent;
1036
1037         priv = container_of(work, struct ccw_device_private, kick_work);
1038         sch = priv->sch;
1039         cdev = priv->cdev;
1040         former_parent = ccw_device_is_orphan(cdev) ?
1041                 NULL : to_subchannel(get_device(cdev->dev.parent));
1042         mutex_lock(&sch->reg_mutex);
1043         /* Try to move the ccw device to its new subchannel. */
1044         rc = device_move(&cdev->dev, &sch->dev);
1045         mutex_unlock(&sch->reg_mutex);
1046         if (rc) {
1047                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1048                               "0.%x.%04x failed (ret=%d)!\n",
1049                               cdev->private->dev_id.ssid,
1050                               cdev->private->dev_id.devno, sch->schid.ssid,
1051                               sch->schid.sch_no, rc);
1052                 css_sch_device_unregister(sch);
1053                 goto out;
1054         }
1055         if (former_parent) {
1056                 spin_lock_irq(former_parent->lock);
1057                 former_parent->dev.driver_data = NULL;
1058                 spin_unlock_irq(former_parent->lock);
1059                 css_sch_device_unregister(former_parent);
1060                 /* Reset intparm to zeroes. */
1061                 former_parent->schib.pmcw.intparm = 0;
1062                 cio_modify(former_parent);
1063         }
1064         sch_attach_device(sch, cdev);
1065 out:
1066         if (former_parent)
1067                 put_device(&former_parent->dev);
1068         put_device(&cdev->dev);
1069 }
1070
1071 static int
1072 io_subchannel_probe (struct subchannel *sch)
1073 {
1074         struct ccw_device *cdev;
1075         int rc;
1076         unsigned long flags;
1077         struct ccw_dev_id dev_id;
1078
1079         if (sch->dev.driver_data) {
1080                 /*
1081                  * This subchannel already has an associated ccw_device.
1082                  * Register it and exit. This happens for all early
1083                  * device, e.g. the console.
1084                  */
1085                 cdev = sch->dev.driver_data;
1086                 device_initialize(&cdev->dev);
1087                 ccw_device_register(cdev);
1088                 /*
1089                  * Check if the device is already online. If it is
1090                  * the reference count needs to be corrected
1091                  * (see ccw_device_online and css_init_done for the
1092                  * ugly details).
1093                  */
1094                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1095                     cdev->private->state != DEV_STATE_OFFLINE &&
1096                     cdev->private->state != DEV_STATE_BOXED)
1097                         get_device(&cdev->dev);
1098                 return 0;
1099         }
1100         /*
1101          * First check if a fitting device may be found amongst the
1102          * disconnected devices or in the orphanage.
1103          */
1104         dev_id.devno = sch->schib.pmcw.dev;
1105         dev_id.ssid = sch->schid.ssid;
1106         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1107         if (!cdev)
1108                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1109                                                      &dev_id);
1110         if (cdev) {
1111                 /*
1112                  * Schedule moving the device until when we have a registered
1113                  * subchannel to move to and succeed the probe. We can
1114                  * unregister later again, when the probe is through.
1115                  */
1116                 cdev->private->sch = sch;
1117                 PREPARE_WORK(&cdev->private->kick_work,
1118                              ccw_device_move_to_sch);
1119                 queue_work(slow_path_wq, &cdev->private->kick_work);
1120                 return 0;
1121         }
1122         cdev = io_subchannel_create_ccwdev(sch);
1123         if (IS_ERR(cdev))
1124                 return PTR_ERR(cdev);
1125
1126         rc = io_subchannel_recog(cdev, sch);
1127         if (rc) {
1128                 spin_lock_irqsave(sch->lock, flags);
1129                 sch->dev.driver_data = NULL;
1130                 spin_unlock_irqrestore(sch->lock, flags);
1131                 if (cdev->dev.release)
1132                         cdev->dev.release(&cdev->dev);
1133         }
1134
1135         return rc;
1136 }
1137
1138 static int
1139 io_subchannel_remove (struct subchannel *sch)
1140 {
1141         struct ccw_device *cdev;
1142         unsigned long flags;
1143
1144         if (!sch->dev.driver_data)
1145                 return 0;
1146         cdev = sch->dev.driver_data;
1147         /* Set ccw device to not operational and drop reference. */
1148         spin_lock_irqsave(cdev->ccwlock, flags);
1149         sch->dev.driver_data = NULL;
1150         cdev->private->state = DEV_STATE_NOT_OPER;
1151         spin_unlock_irqrestore(cdev->ccwlock, flags);
1152         ccw_device_unregister(cdev);
1153         put_device(&cdev->dev);
1154         return 0;
1155 }
1156
1157 static int
1158 io_subchannel_notify(struct device *dev, int event)
1159 {
1160         struct ccw_device *cdev;
1161
1162         cdev = dev->driver_data;
1163         if (!cdev)
1164                 return 0;
1165         if (!cdev->drv)
1166                 return 0;
1167         if (!cdev->online)
1168                 return 0;
1169         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1170 }
1171
1172 static void
1173 io_subchannel_verify(struct device *dev)
1174 {
1175         struct ccw_device *cdev;
1176
1177         cdev = dev->driver_data;
1178         if (cdev)
1179                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1180 }
1181
1182 static void
1183 io_subchannel_ioterm(struct device *dev)
1184 {
1185         struct ccw_device *cdev;
1186
1187         cdev = dev->driver_data;
1188         if (!cdev)
1189                 return;
1190         /* Internal I/O will be retried by the interrupt handler. */
1191         if (cdev->private->flags.intretry)
1192                 return;
1193         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1194         if (cdev->handler)
1195                 cdev->handler(cdev, cdev->private->intparm,
1196                               ERR_PTR(-EIO));
1197 }
1198
1199 static void
1200 io_subchannel_shutdown(struct subchannel *sch)
1201 {
1202         struct ccw_device *cdev;
1203         int ret;
1204
1205         cdev = sch->dev.driver_data;
1206
1207         if (cio_is_console(sch->schid))
1208                 return;
1209         if (!sch->schib.pmcw.ena)
1210                 /* Nothing to do. */
1211                 return;
1212         ret = cio_disable_subchannel(sch);
1213         if (ret != -EBUSY)
1214                 /* Subchannel is disabled, we're done. */
1215                 return;
1216         cdev->private->state = DEV_STATE_QUIESCE;
1217         if (cdev->handler)
1218                 cdev->handler(cdev, cdev->private->intparm,
1219                               ERR_PTR(-EIO));
1220         ret = ccw_device_cancel_halt_clear(cdev);
1221         if (ret == -EBUSY) {
1222                 ccw_device_set_timeout(cdev, HZ/10);
1223                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1224         }
1225         cio_disable_subchannel(sch);
1226 }
1227
1228 #ifdef CONFIG_CCW_CONSOLE
1229 static struct ccw_device console_cdev;
1230 static struct ccw_device_private console_private;
1231 static int console_cdev_in_use;
1232
1233 static DEFINE_SPINLOCK(ccw_console_lock);
1234
1235 spinlock_t * cio_get_console_lock(void)
1236 {
1237         return &ccw_console_lock;
1238 }
1239
1240 static int
1241 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1242 {
1243         int rc;
1244
1245         /* Initialize the ccw_device structure. */
1246         cdev->dev.parent= &sch->dev;
1247         rc = io_subchannel_recog(cdev, sch);
1248         if (rc)
1249                 return rc;
1250
1251         /* Now wait for the async. recognition to come to an end. */
1252         spin_lock_irq(cdev->ccwlock);
1253         while (!dev_fsm_final_state(cdev))
1254                 wait_cons_dev();
1255         rc = -EIO;
1256         if (cdev->private->state != DEV_STATE_OFFLINE)
1257                 goto out_unlock;
1258         ccw_device_online(cdev);
1259         while (!dev_fsm_final_state(cdev))
1260                 wait_cons_dev();
1261         if (cdev->private->state != DEV_STATE_ONLINE)
1262                 goto out_unlock;
1263         rc = 0;
1264 out_unlock:
1265         spin_unlock_irq(cdev->ccwlock);
1266         return 0;
1267 }
1268
1269 struct ccw_device *
1270 ccw_device_probe_console(void)
1271 {
1272         struct subchannel *sch;
1273         int ret;
1274
1275         if (xchg(&console_cdev_in_use, 1) != 0)
1276                 return ERR_PTR(-EBUSY);
1277         sch = cio_probe_console();
1278         if (IS_ERR(sch)) {
1279                 console_cdev_in_use = 0;
1280                 return (void *) sch;
1281         }
1282         memset(&console_cdev, 0, sizeof(struct ccw_device));
1283         memset(&console_private, 0, sizeof(struct ccw_device_private));
1284         console_cdev.private = &console_private;
1285         console_private.cdev = &console_cdev;
1286         ret = ccw_device_console_enable(&console_cdev, sch);
1287         if (ret) {
1288                 cio_release_console();
1289                 console_cdev_in_use = 0;
1290                 return ERR_PTR(ret);
1291         }
1292         console_cdev.online = 1;
1293         return &console_cdev;
1294 }
1295 #endif
1296
1297 /*
1298  * get ccw_device matching the busid, but only if owned by cdrv
1299  */
1300 static int
1301 __ccwdev_check_busid(struct device *dev, void *id)
1302 {
1303         char *bus_id;
1304
1305         bus_id = id;
1306
1307         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1308 }
1309
1310
1311 struct ccw_device *
1312 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1313 {
1314         struct device *dev;
1315         struct device_driver *drv;
1316
1317         drv = get_driver(&cdrv->driver);
1318         if (!drv)
1319                 return NULL;
1320
1321         dev = driver_find_device(drv, NULL, (void *)bus_id,
1322                                  __ccwdev_check_busid);
1323         put_driver(drv);
1324
1325         return dev ? to_ccwdev(dev) : NULL;
1326 }
1327
1328 /************************** device driver handling ************************/
1329
1330 /* This is the implementation of the ccw_driver class. The probe, remove
1331  * and release methods are initially very similar to the device_driver
1332  * implementations, with the difference that they have ccw_device
1333  * arguments.
1334  *
1335  * A ccw driver also contains the information that is needed for
1336  * device matching.
1337  */
1338 static int
1339 ccw_device_probe (struct device *dev)
1340 {
1341         struct ccw_device *cdev = to_ccwdev(dev);
1342         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1343         int ret;
1344
1345         cdev->drv = cdrv; /* to let the driver call _set_online */
1346
1347         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1348
1349         if (ret) {
1350                 cdev->drv = NULL;
1351                 return ret;
1352         }
1353
1354         return 0;
1355 }
1356
1357 static int
1358 ccw_device_remove (struct device *dev)
1359 {
1360         struct ccw_device *cdev = to_ccwdev(dev);
1361         struct ccw_driver *cdrv = cdev->drv;
1362         int ret;
1363
1364         pr_debug("removing device %s\n", cdev->dev.bus_id);
1365         if (cdrv->remove)
1366                 cdrv->remove(cdev);
1367         if (cdev->online) {
1368                 cdev->online = 0;
1369                 spin_lock_irq(cdev->ccwlock);
1370                 ret = ccw_device_offline(cdev);
1371                 spin_unlock_irq(cdev->ccwlock);
1372                 if (ret == 0)
1373                         wait_event(cdev->private->wait_q,
1374                                    dev_fsm_final_state(cdev));
1375                 else
1376                         //FIXME: we can't fail!
1377                         pr_debug("ccw_device_offline returned %d, device %s\n",
1378                                  ret, cdev->dev.bus_id);
1379         }
1380         ccw_device_set_timeout(cdev, 0);
1381         cdev->drv = NULL;
1382         return 0;
1383 }
1384
1385 struct bus_type ccw_bus_type = {
1386         .name   = "ccw",
1387         .match  = ccw_bus_match,
1388         .uevent = ccw_uevent,
1389         .probe  = ccw_device_probe,
1390         .remove = ccw_device_remove,
1391 };
1392
1393 int
1394 ccw_driver_register (struct ccw_driver *cdriver)
1395 {
1396         struct device_driver *drv = &cdriver->driver;
1397
1398         drv->bus = &ccw_bus_type;
1399         drv->name = cdriver->name;
1400
1401         return driver_register(drv);
1402 }
1403
1404 void
1405 ccw_driver_unregister (struct ccw_driver *cdriver)
1406 {
1407         driver_unregister(&cdriver->driver);
1408 }
1409
1410 /* Helper func for qdio. */
1411 struct subchannel_id
1412 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1413 {
1414         struct subchannel *sch;
1415
1416         sch = to_subchannel(cdev->dev.parent);
1417         return sch->schid;
1418 }
1419
1420 MODULE_LICENSE("GPL");
1421 EXPORT_SYMBOL(ccw_device_set_online);
1422 EXPORT_SYMBOL(ccw_device_set_offline);
1423 EXPORT_SYMBOL(ccw_driver_register);
1424 EXPORT_SYMBOL(ccw_driver_unregister);
1425 EXPORT_SYMBOL(get_ccwdev_by_busid);
1426 EXPORT_SYMBOL(ccw_bus_type);
1427 EXPORT_SYMBOL(ccw_device_work);
1428 EXPORT_SYMBOL(ccw_device_notify_work);
1429 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);