Merge branch 'samsung/exynos5' into next/soc2
[linux-2.6.git] / drivers / s390 / cio / device.c
1 /*
2  *  drivers/s390/cio/device.c
3  *  bus driver for ccw devices
4  *
5  *    Copyright IBM Corp. 2002,2008
6  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
8  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
9  */
10
11 #define KMSG_COMPONENT "cio"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/spinlock.h>
17 #include <linux/errno.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/list.h>
21 #include <linux/device.h>
22 #include <linux/workqueue.h>
23 #include <linux/timer.h>
24 #include <linux/kernel_stat.h>
25
26 #include <asm/ccwdev.h>
27 #include <asm/cio.h>
28 #include <asm/param.h>          /* HZ */
29 #include <asm/cmb.h>
30 #include <asm/isc.h>
31
32 #include "chp.h"
33 #include "cio.h"
34 #include "cio_debug.h"
35 #include "css.h"
36 #include "device.h"
37 #include "ioasm.h"
38 #include "io_sch.h"
39 #include "blacklist.h"
40 #include "chsc.h"
41
42 static struct timer_list recovery_timer;
43 static DEFINE_SPINLOCK(recovery_lock);
44 static int recovery_phase;
45 static const unsigned long recovery_delay[] = { 3, 30, 300 };
46
47 /******************* bus type handling ***********************/
48
49 /* The Linux driver model distinguishes between a bus type and
50  * the bus itself. Of course we only have one channel
51  * subsystem driver and one channel system per machine, but
52  * we still use the abstraction. T.R. says it's a good idea. */
53 static int
54 ccw_bus_match (struct device * dev, struct device_driver * drv)
55 {
56         struct ccw_device *cdev = to_ccwdev(dev);
57         struct ccw_driver *cdrv = to_ccwdrv(drv);
58         const struct ccw_device_id *ids = cdrv->ids, *found;
59
60         if (!ids)
61                 return 0;
62
63         found = ccw_device_id_match(ids, &cdev->id);
64         if (!found)
65                 return 0;
66
67         cdev->id.driver_info = found->driver_info;
68
69         return 1;
70 }
71
72 /* Store modalias string delimited by prefix/suffix string into buffer with
73  * specified size. Return length of resulting string (excluding trailing '\0')
74  * even if string doesn't fit buffer (snprintf semantics). */
75 static int snprint_alias(char *buf, size_t size,
76                          struct ccw_device_id *id, const char *suffix)
77 {
78         int len;
79
80         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
81         if (len > size)
82                 return len;
83         buf += len;
84         size -= len;
85
86         if (id->dev_type != 0)
87                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
88                                 id->dev_model, suffix);
89         else
90                 len += snprintf(buf, size, "dtdm%s", suffix);
91
92         return len;
93 }
94
95 /* Set up environment variables for ccw device uevent. Return 0 on success,
96  * non-zero otherwise. */
97 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
98 {
99         struct ccw_device *cdev = to_ccwdev(dev);
100         struct ccw_device_id *id = &(cdev->id);
101         int ret;
102         char modalias_buf[30];
103
104         /* CU_TYPE= */
105         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
106         if (ret)
107                 return ret;
108
109         /* CU_MODEL= */
110         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
111         if (ret)
112                 return ret;
113
114         /* The next two can be zero, that's ok for us */
115         /* DEV_TYPE= */
116         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
117         if (ret)
118                 return ret;
119
120         /* DEV_MODEL= */
121         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
122         if (ret)
123                 return ret;
124
125         /* MODALIAS=  */
126         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
127         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
128         return ret;
129 }
130
131 static struct bus_type ccw_bus_type;
132
133 static void io_subchannel_irq(struct subchannel *);
134 static int io_subchannel_probe(struct subchannel *);
135 static int io_subchannel_remove(struct subchannel *);
136 static void io_subchannel_shutdown(struct subchannel *);
137 static int io_subchannel_sch_event(struct subchannel *, int);
138 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
139                                    int);
140 static void recovery_func(unsigned long data);
141 wait_queue_head_t ccw_device_init_wq;
142 atomic_t ccw_device_init_count;
143
144 static struct css_device_id io_subchannel_ids[] = {
145         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
146         { /* end of list */ },
147 };
148 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
149
150 static int io_subchannel_prepare(struct subchannel *sch)
151 {
152         struct ccw_device *cdev;
153         /*
154          * Don't allow suspend while a ccw device registration
155          * is still outstanding.
156          */
157         cdev = sch_get_cdev(sch);
158         if (cdev && !device_is_registered(&cdev->dev))
159                 return -EAGAIN;
160         return 0;
161 }
162
163 static int io_subchannel_settle(void)
164 {
165         int ret;
166
167         ret = wait_event_interruptible(ccw_device_init_wq,
168                                 atomic_read(&ccw_device_init_count) == 0);
169         if (ret)
170                 return -EINTR;
171         flush_workqueue(cio_work_q);
172         return 0;
173 }
174
175 static struct css_driver io_subchannel_driver = {
176         .drv = {
177                 .owner = THIS_MODULE,
178                 .name = "io_subchannel",
179         },
180         .subchannel_type = io_subchannel_ids,
181         .irq = io_subchannel_irq,
182         .sch_event = io_subchannel_sch_event,
183         .chp_event = io_subchannel_chp_event,
184         .probe = io_subchannel_probe,
185         .remove = io_subchannel_remove,
186         .shutdown = io_subchannel_shutdown,
187         .prepare = io_subchannel_prepare,
188         .settle = io_subchannel_settle,
189 };
190
191 int __init io_subchannel_init(void)
192 {
193         int ret;
194
195         init_waitqueue_head(&ccw_device_init_wq);
196         atomic_set(&ccw_device_init_count, 0);
197         setup_timer(&recovery_timer, recovery_func, 0);
198
199         ret = bus_register(&ccw_bus_type);
200         if (ret)
201                 return ret;
202         ret = css_driver_register(&io_subchannel_driver);
203         if (ret)
204                 bus_unregister(&ccw_bus_type);
205
206         return ret;
207 }
208
209
210 /************************ device handling **************************/
211
212 /*
213  * A ccw_device has some interfaces in sysfs in addition to the
214  * standard ones.
215  * The following entries are designed to export the information which
216  * resided in 2.4 in /proc/subchannels. Subchannel and device number
217  * are obvious, so they don't have an entry :)
218  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
219  */
220 static ssize_t
221 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
222 {
223         struct subchannel *sch = to_subchannel(dev);
224         struct chsc_ssd_info *ssd = &sch->ssd_info;
225         ssize_t ret = 0;
226         int chp;
227         int mask;
228
229         for (chp = 0; chp < 8; chp++) {
230                 mask = 0x80 >> chp;
231                 if (ssd->path_mask & mask)
232                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
233                 else
234                         ret += sprintf(buf + ret, "00 ");
235         }
236         ret += sprintf (buf+ret, "\n");
237         return min((ssize_t)PAGE_SIZE, ret);
238 }
239
240 static ssize_t
241 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
242 {
243         struct subchannel *sch = to_subchannel(dev);
244         struct pmcw *pmcw = &sch->schib.pmcw;
245
246         return sprintf (buf, "%02x %02x %02x\n",
247                         pmcw->pim, pmcw->pam, pmcw->pom);
248 }
249
250 static ssize_t
251 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
252 {
253         struct ccw_device *cdev = to_ccwdev(dev);
254         struct ccw_device_id *id = &(cdev->id);
255
256         if (id->dev_type != 0)
257                 return sprintf(buf, "%04x/%02x\n",
258                                 id->dev_type, id->dev_model);
259         else
260                 return sprintf(buf, "n/a\n");
261 }
262
263 static ssize_t
264 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
265 {
266         struct ccw_device *cdev = to_ccwdev(dev);
267         struct ccw_device_id *id = &(cdev->id);
268
269         return sprintf(buf, "%04x/%02x\n",
270                        id->cu_type, id->cu_model);
271 }
272
273 static ssize_t
274 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
275 {
276         struct ccw_device *cdev = to_ccwdev(dev);
277         struct ccw_device_id *id = &(cdev->id);
278         int len;
279
280         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
281
282         return len > PAGE_SIZE ? PAGE_SIZE : len;
283 }
284
285 static ssize_t
286 online_show (struct device *dev, struct device_attribute *attr, char *buf)
287 {
288         struct ccw_device *cdev = to_ccwdev(dev);
289
290         return sprintf(buf, cdev->online ? "1\n" : "0\n");
291 }
292
293 int ccw_device_is_orphan(struct ccw_device *cdev)
294 {
295         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
296 }
297
298 static void ccw_device_unregister(struct ccw_device *cdev)
299 {
300         if (device_is_registered(&cdev->dev)) {
301                 /* Undo device_add(). */
302                 device_del(&cdev->dev);
303         }
304         if (cdev->private->flags.initialized) {
305                 cdev->private->flags.initialized = 0;
306                 /* Release reference from device_initialize(). */
307                 put_device(&cdev->dev);
308         }
309 }
310
311 static void io_subchannel_quiesce(struct subchannel *);
312
313 /**
314  * ccw_device_set_offline() - disable a ccw device for I/O
315  * @cdev: target ccw device
316  *
317  * This function calls the driver's set_offline() function for @cdev, if
318  * given, and then disables @cdev.
319  * Returns:
320  *   %0 on success and a negative error value on failure.
321  * Context:
322  *  enabled, ccw device lock not held
323  */
324 int ccw_device_set_offline(struct ccw_device *cdev)
325 {
326         struct subchannel *sch;
327         int ret, state;
328
329         if (!cdev)
330                 return -ENODEV;
331         if (!cdev->online || !cdev->drv)
332                 return -EINVAL;
333
334         if (cdev->drv->set_offline) {
335                 ret = cdev->drv->set_offline(cdev);
336                 if (ret != 0)
337                         return ret;
338         }
339         cdev->online = 0;
340         spin_lock_irq(cdev->ccwlock);
341         sch = to_subchannel(cdev->dev.parent);
342         /* Wait until a final state or DISCONNECTED is reached */
343         while (!dev_fsm_final_state(cdev) &&
344                cdev->private->state != DEV_STATE_DISCONNECTED) {
345                 spin_unlock_irq(cdev->ccwlock);
346                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
347                            cdev->private->state == DEV_STATE_DISCONNECTED));
348                 spin_lock_irq(cdev->ccwlock);
349         }
350         do {
351                 ret = ccw_device_offline(cdev);
352                 if (!ret)
353                         break;
354                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
355                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
356                               cdev->private->dev_id.devno);
357                 if (ret != -EBUSY)
358                         goto error;
359                 state = cdev->private->state;
360                 spin_unlock_irq(cdev->ccwlock);
361                 io_subchannel_quiesce(sch);
362                 spin_lock_irq(cdev->ccwlock);
363                 cdev->private->state = state;
364         } while (ret == -EBUSY);
365         spin_unlock_irq(cdev->ccwlock);
366         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
367                    cdev->private->state == DEV_STATE_DISCONNECTED));
368         /* Inform the user if set offline failed. */
369         if (cdev->private->state == DEV_STATE_BOXED) {
370                 pr_warning("%s: The device entered boxed state while "
371                            "being set offline\n", dev_name(&cdev->dev));
372         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
373                 pr_warning("%s: The device stopped operating while "
374                            "being set offline\n", dev_name(&cdev->dev));
375         }
376         /* Give up reference from ccw_device_set_online(). */
377         put_device(&cdev->dev);
378         return 0;
379
380 error:
381         cdev->private->state = DEV_STATE_OFFLINE;
382         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
383         spin_unlock_irq(cdev->ccwlock);
384         /* Give up reference from ccw_device_set_online(). */
385         put_device(&cdev->dev);
386         return -ENODEV;
387 }
388
389 /**
390  * ccw_device_set_online() - enable a ccw device for I/O
391  * @cdev: target ccw device
392  *
393  * This function first enables @cdev and then calls the driver's set_online()
394  * function for @cdev, if given. If set_online() returns an error, @cdev is
395  * disabled again.
396  * Returns:
397  *   %0 on success and a negative error value on failure.
398  * Context:
399  *  enabled, ccw device lock not held
400  */
401 int ccw_device_set_online(struct ccw_device *cdev)
402 {
403         int ret;
404         int ret2;
405
406         if (!cdev)
407                 return -ENODEV;
408         if (cdev->online || !cdev->drv)
409                 return -EINVAL;
410         /* Hold on to an extra reference while device is online. */
411         if (!get_device(&cdev->dev))
412                 return -ENODEV;
413
414         spin_lock_irq(cdev->ccwlock);
415         ret = ccw_device_online(cdev);
416         spin_unlock_irq(cdev->ccwlock);
417         if (ret == 0)
418                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
419         else {
420                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
421                               "device 0.%x.%04x\n",
422                               ret, cdev->private->dev_id.ssid,
423                               cdev->private->dev_id.devno);
424                 /* Give up online reference since onlining failed. */
425                 put_device(&cdev->dev);
426                 return ret;
427         }
428         spin_lock_irq(cdev->ccwlock);
429         /* Check if online processing was successful */
430         if ((cdev->private->state != DEV_STATE_ONLINE) &&
431             (cdev->private->state != DEV_STATE_W4SENSE)) {
432                 spin_unlock_irq(cdev->ccwlock);
433                 /* Inform the user that set online failed. */
434                 if (cdev->private->state == DEV_STATE_BOXED) {
435                         pr_warning("%s: Setting the device online failed "
436                                    "because it is boxed\n",
437                                    dev_name(&cdev->dev));
438                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
439                         pr_warning("%s: Setting the device online failed "
440                                    "because it is not operational\n",
441                                    dev_name(&cdev->dev));
442                 }
443                 /* Give up online reference since onlining failed. */
444                 put_device(&cdev->dev);
445                 return -ENODEV;
446         }
447         spin_unlock_irq(cdev->ccwlock);
448         if (cdev->drv->set_online)
449                 ret = cdev->drv->set_online(cdev);
450         if (ret)
451                 goto rollback;
452         cdev->online = 1;
453         return 0;
454
455 rollback:
456         spin_lock_irq(cdev->ccwlock);
457         /* Wait until a final state or DISCONNECTED is reached */
458         while (!dev_fsm_final_state(cdev) &&
459                cdev->private->state != DEV_STATE_DISCONNECTED) {
460                 spin_unlock_irq(cdev->ccwlock);
461                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
462                            cdev->private->state == DEV_STATE_DISCONNECTED));
463                 spin_lock_irq(cdev->ccwlock);
464         }
465         ret2 = ccw_device_offline(cdev);
466         if (ret2)
467                 goto error;
468         spin_unlock_irq(cdev->ccwlock);
469         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
470                    cdev->private->state == DEV_STATE_DISCONNECTED));
471         /* Give up online reference since onlining failed. */
472         put_device(&cdev->dev);
473         return ret;
474
475 error:
476         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
477                       "device 0.%x.%04x\n",
478                       ret2, cdev->private->dev_id.ssid,
479                       cdev->private->dev_id.devno);
480         cdev->private->state = DEV_STATE_OFFLINE;
481         spin_unlock_irq(cdev->ccwlock);
482         /* Give up online reference since onlining failed. */
483         put_device(&cdev->dev);
484         return ret;
485 }
486
487 static int online_store_handle_offline(struct ccw_device *cdev)
488 {
489         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
490                 spin_lock_irq(cdev->ccwlock);
491                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
492                 spin_unlock_irq(cdev->ccwlock);
493                 return 0;
494         }
495         if (cdev->drv && cdev->drv->set_offline)
496                 return ccw_device_set_offline(cdev);
497         return -EINVAL;
498 }
499
500 static int online_store_recog_and_online(struct ccw_device *cdev)
501 {
502         /* Do device recognition, if needed. */
503         if (cdev->private->state == DEV_STATE_BOXED) {
504                 spin_lock_irq(cdev->ccwlock);
505                 ccw_device_recognition(cdev);
506                 spin_unlock_irq(cdev->ccwlock);
507                 wait_event(cdev->private->wait_q,
508                            cdev->private->flags.recog_done);
509                 if (cdev->private->state != DEV_STATE_OFFLINE)
510                         /* recognition failed */
511                         return -EAGAIN;
512         }
513         if (cdev->drv && cdev->drv->set_online)
514                 return ccw_device_set_online(cdev);
515         return -EINVAL;
516 }
517
518 static int online_store_handle_online(struct ccw_device *cdev, int force)
519 {
520         int ret;
521
522         ret = online_store_recog_and_online(cdev);
523         if (ret && !force)
524                 return ret;
525         if (force && cdev->private->state == DEV_STATE_BOXED) {
526                 ret = ccw_device_stlck(cdev);
527                 if (ret)
528                         return ret;
529                 if (cdev->id.cu_type == 0)
530                         cdev->private->state = DEV_STATE_NOT_OPER;
531                 ret = online_store_recog_and_online(cdev);
532                 if (ret)
533                         return ret;
534         }
535         return 0;
536 }
537
538 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
539                              const char *buf, size_t count)
540 {
541         struct ccw_device *cdev = to_ccwdev(dev);
542         int force, ret;
543         unsigned long i;
544
545         /* Prevent conflict between multiple on-/offline processing requests. */
546         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
547                 return -EAGAIN;
548         /* Prevent conflict between internal I/Os and on-/offline processing. */
549         if (!dev_fsm_final_state(cdev) &&
550             cdev->private->state != DEV_STATE_DISCONNECTED) {
551                 ret = -EAGAIN;
552                 goto out_onoff;
553         }
554         /* Prevent conflict between pending work and on-/offline processing.*/
555         if (work_pending(&cdev->private->todo_work)) {
556                 ret = -EAGAIN;
557                 goto out_onoff;
558         }
559
560         if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
561                 ret = -EINVAL;
562                 goto out_onoff;
563         }
564         if (!strncmp(buf, "force\n", count)) {
565                 force = 1;
566                 i = 1;
567                 ret = 0;
568         } else {
569                 force = 0;
570                 ret = strict_strtoul(buf, 16, &i);
571         }
572         if (ret)
573                 goto out;
574         switch (i) {
575         case 0:
576                 ret = online_store_handle_offline(cdev);
577                 break;
578         case 1:
579                 ret = online_store_handle_online(cdev, force);
580                 break;
581         default:
582                 ret = -EINVAL;
583         }
584 out:
585         if (cdev->drv)
586                 module_put(cdev->drv->driver.owner);
587 out_onoff:
588         atomic_set(&cdev->private->onoff, 0);
589         return (ret < 0) ? ret : count;
590 }
591
592 static ssize_t
593 available_show (struct device *dev, struct device_attribute *attr, char *buf)
594 {
595         struct ccw_device *cdev = to_ccwdev(dev);
596         struct subchannel *sch;
597
598         if (ccw_device_is_orphan(cdev))
599                 return sprintf(buf, "no device\n");
600         switch (cdev->private->state) {
601         case DEV_STATE_BOXED:
602                 return sprintf(buf, "boxed\n");
603         case DEV_STATE_DISCONNECTED:
604         case DEV_STATE_DISCONNECTED_SENSE_ID:
605         case DEV_STATE_NOT_OPER:
606                 sch = to_subchannel(dev->parent);
607                 if (!sch->lpm)
608                         return sprintf(buf, "no path\n");
609                 else
610                         return sprintf(buf, "no device\n");
611         default:
612                 /* All other states considered fine. */
613                 return sprintf(buf, "good\n");
614         }
615 }
616
617 static ssize_t
618 initiate_logging(struct device *dev, struct device_attribute *attr,
619                  const char *buf, size_t count)
620 {
621         struct subchannel *sch = to_subchannel(dev);
622         int rc;
623
624         rc = chsc_siosl(sch->schid);
625         if (rc < 0) {
626                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
627                            "errno=%d\n",
628                            sch->schid.ssid, sch->schid.sch_no, rc);
629                 return rc;
630         }
631         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
632                   sch->schid.ssid, sch->schid.sch_no);
633         return count;
634 }
635
636 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
637 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
638 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
639 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
640 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
641 static DEVICE_ATTR(online, 0644, online_show, online_store);
642 static DEVICE_ATTR(availability, 0444, available_show, NULL);
643 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
644
645 static struct attribute *io_subchannel_attrs[] = {
646         &dev_attr_chpids.attr,
647         &dev_attr_pimpampom.attr,
648         &dev_attr_logging.attr,
649         NULL,
650 };
651
652 static struct attribute_group io_subchannel_attr_group = {
653         .attrs = io_subchannel_attrs,
654 };
655
656 static struct attribute * ccwdev_attrs[] = {
657         &dev_attr_devtype.attr,
658         &dev_attr_cutype.attr,
659         &dev_attr_modalias.attr,
660         &dev_attr_online.attr,
661         &dev_attr_cmb_enable.attr,
662         &dev_attr_availability.attr,
663         NULL,
664 };
665
666 static struct attribute_group ccwdev_attr_group = {
667         .attrs = ccwdev_attrs,
668 };
669
670 static const struct attribute_group *ccwdev_attr_groups[] = {
671         &ccwdev_attr_group,
672         NULL,
673 };
674
675 /* this is a simple abstraction for device_register that sets the
676  * correct bus type and adds the bus specific files */
677 static int ccw_device_register(struct ccw_device *cdev)
678 {
679         struct device *dev = &cdev->dev;
680         int ret;
681
682         dev->bus = &ccw_bus_type;
683         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
684                            cdev->private->dev_id.devno);
685         if (ret)
686                 return ret;
687         return device_add(dev);
688 }
689
690 static int match_dev_id(struct device *dev, void *data)
691 {
692         struct ccw_device *cdev = to_ccwdev(dev);
693         struct ccw_dev_id *dev_id = data;
694
695         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
696 }
697
698 static struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
699 {
700         struct device *dev;
701
702         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
703
704         return dev ? to_ccwdev(dev) : NULL;
705 }
706
707 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
708 {
709         int ret;
710
711         if (device_is_registered(&cdev->dev)) {
712                 device_release_driver(&cdev->dev);
713                 ret = device_attach(&cdev->dev);
714                 WARN_ON(ret == -ENODEV);
715         }
716 }
717
718 static void
719 ccw_device_release(struct device *dev)
720 {
721         struct ccw_device *cdev;
722
723         cdev = to_ccwdev(dev);
724         /* Release reference of parent subchannel. */
725         put_device(cdev->dev.parent);
726         kfree(cdev->private);
727         kfree(cdev);
728 }
729
730 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
731 {
732         struct ccw_device *cdev;
733
734         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
735         if (cdev) {
736                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
737                                         GFP_KERNEL | GFP_DMA);
738                 if (cdev->private)
739                         return cdev;
740         }
741         kfree(cdev);
742         return ERR_PTR(-ENOMEM);
743 }
744
745 static void ccw_device_todo(struct work_struct *work);
746
747 static int io_subchannel_initialize_dev(struct subchannel *sch,
748                                         struct ccw_device *cdev)
749 {
750         cdev->private->cdev = cdev;
751         cdev->private->int_class = IOINT_CIO;
752         atomic_set(&cdev->private->onoff, 0);
753         cdev->dev.parent = &sch->dev;
754         cdev->dev.release = ccw_device_release;
755         INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
756         cdev->dev.groups = ccwdev_attr_groups;
757         /* Do first half of device_register. */
758         device_initialize(&cdev->dev);
759         if (!get_device(&sch->dev)) {
760                 /* Release reference from device_initialize(). */
761                 put_device(&cdev->dev);
762                 return -ENODEV;
763         }
764         cdev->private->flags.initialized = 1;
765         return 0;
766 }
767
768 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
769 {
770         struct ccw_device *cdev;
771         int ret;
772
773         cdev = io_subchannel_allocate_dev(sch);
774         if (!IS_ERR(cdev)) {
775                 ret = io_subchannel_initialize_dev(sch, cdev);
776                 if (ret)
777                         cdev = ERR_PTR(ret);
778         }
779         return cdev;
780 }
781
782 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
783
784 static void sch_create_and_recog_new_device(struct subchannel *sch)
785 {
786         struct ccw_device *cdev;
787
788         /* Need to allocate a new ccw device. */
789         cdev = io_subchannel_create_ccwdev(sch);
790         if (IS_ERR(cdev)) {
791                 /* OK, we did everything we could... */
792                 css_sch_device_unregister(sch);
793                 return;
794         }
795         /* Start recognition for the new ccw device. */
796         io_subchannel_recog(cdev, sch);
797 }
798
799 /*
800  * Register recognized device.
801  */
802 static void io_subchannel_register(struct ccw_device *cdev)
803 {
804         struct subchannel *sch;
805         int ret, adjust_init_count = 1;
806         unsigned long flags;
807
808         sch = to_subchannel(cdev->dev.parent);
809         /*
810          * Check if subchannel is still registered. It may have become
811          * unregistered if a machine check hit us after finishing
812          * device recognition but before the register work could be
813          * queued.
814          */
815         if (!device_is_registered(&sch->dev))
816                 goto out_err;
817         css_update_ssd_info(sch);
818         /*
819          * io_subchannel_register() will also be called after device
820          * recognition has been done for a boxed device (which will already
821          * be registered). We need to reprobe since we may now have sense id
822          * information.
823          */
824         if (device_is_registered(&cdev->dev)) {
825                 if (!cdev->drv) {
826                         ret = device_reprobe(&cdev->dev);
827                         if (ret)
828                                 /* We can't do much here. */
829                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
830                                               " %d for 0.%x.%04x\n", ret,
831                                               cdev->private->dev_id.ssid,
832                                               cdev->private->dev_id.devno);
833                 }
834                 adjust_init_count = 0;
835                 goto out;
836         }
837         /*
838          * Now we know this subchannel will stay, we can throw
839          * our delayed uevent.
840          */
841         dev_set_uevent_suppress(&sch->dev, 0);
842         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
843         /* make it known to the system */
844         ret = ccw_device_register(cdev);
845         if (ret) {
846                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
847                               cdev->private->dev_id.ssid,
848                               cdev->private->dev_id.devno, ret);
849                 spin_lock_irqsave(sch->lock, flags);
850                 sch_set_cdev(sch, NULL);
851                 spin_unlock_irqrestore(sch->lock, flags);
852                 /* Release initial device reference. */
853                 put_device(&cdev->dev);
854                 goto out_err;
855         }
856 out:
857         cdev->private->flags.recog_done = 1;
858         wake_up(&cdev->private->wait_q);
859 out_err:
860         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
861                 wake_up(&ccw_device_init_wq);
862 }
863
864 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
865 {
866         struct subchannel *sch;
867
868         /* Get subchannel reference for local processing. */
869         if (!get_device(cdev->dev.parent))
870                 return;
871         sch = to_subchannel(cdev->dev.parent);
872         css_sch_device_unregister(sch);
873         /* Release subchannel reference for local processing. */
874         put_device(&sch->dev);
875 }
876
877 /*
878  * subchannel recognition done. Called from the state machine.
879  */
880 void
881 io_subchannel_recog_done(struct ccw_device *cdev)
882 {
883         if (css_init_done == 0) {
884                 cdev->private->flags.recog_done = 1;
885                 return;
886         }
887         switch (cdev->private->state) {
888         case DEV_STATE_BOXED:
889                 /* Device did not respond in time. */
890         case DEV_STATE_NOT_OPER:
891                 cdev->private->flags.recog_done = 1;
892                 /* Remove device found not operational. */
893                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
894                 if (atomic_dec_and_test(&ccw_device_init_count))
895                         wake_up(&ccw_device_init_wq);
896                 break;
897         case DEV_STATE_OFFLINE:
898                 /* 
899                  * We can't register the device in interrupt context so
900                  * we schedule a work item.
901                  */
902                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
903                 break;
904         }
905 }
906
907 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
908 {
909         struct ccw_device_private *priv;
910
911         cdev->ccwlock = sch->lock;
912
913         /* Init private data. */
914         priv = cdev->private;
915         priv->dev_id.devno = sch->schib.pmcw.dev;
916         priv->dev_id.ssid = sch->schid.ssid;
917         priv->schid = sch->schid;
918         priv->state = DEV_STATE_NOT_OPER;
919         INIT_LIST_HEAD(&priv->cmb_list);
920         init_waitqueue_head(&priv->wait_q);
921         init_timer(&priv->timer);
922
923         /* Increase counter of devices currently in recognition. */
924         atomic_inc(&ccw_device_init_count);
925
926         /* Start async. device sensing. */
927         spin_lock_irq(sch->lock);
928         sch_set_cdev(sch, cdev);
929         ccw_device_recognition(cdev);
930         spin_unlock_irq(sch->lock);
931 }
932
933 static int ccw_device_move_to_sch(struct ccw_device *cdev,
934                                   struct subchannel *sch)
935 {
936         struct subchannel *old_sch;
937         int rc, old_enabled = 0;
938
939         old_sch = to_subchannel(cdev->dev.parent);
940         /* Obtain child reference for new parent. */
941         if (!get_device(&sch->dev))
942                 return -ENODEV;
943
944         if (!sch_is_pseudo_sch(old_sch)) {
945                 spin_lock_irq(old_sch->lock);
946                 old_enabled = old_sch->schib.pmcw.ena;
947                 rc = 0;
948                 if (old_enabled)
949                         rc = cio_disable_subchannel(old_sch);
950                 spin_unlock_irq(old_sch->lock);
951                 if (rc == -EBUSY) {
952                         /* Release child reference for new parent. */
953                         put_device(&sch->dev);
954                         return rc;
955                 }
956         }
957
958         mutex_lock(&sch->reg_mutex);
959         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
960         mutex_unlock(&sch->reg_mutex);
961         if (rc) {
962                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
963                               cdev->private->dev_id.ssid,
964                               cdev->private->dev_id.devno, sch->schid.ssid,
965                               sch->schib.pmcw.dev, rc);
966                 if (old_enabled) {
967                         /* Try to reenable the old subchannel. */
968                         spin_lock_irq(old_sch->lock);
969                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
970                         spin_unlock_irq(old_sch->lock);
971                 }
972                 /* Release child reference for new parent. */
973                 put_device(&sch->dev);
974                 return rc;
975         }
976         /* Clean up old subchannel. */
977         if (!sch_is_pseudo_sch(old_sch)) {
978                 spin_lock_irq(old_sch->lock);
979                 sch_set_cdev(old_sch, NULL);
980                 spin_unlock_irq(old_sch->lock);
981                 css_schedule_eval(old_sch->schid);
982         }
983         /* Release child reference for old parent. */
984         put_device(&old_sch->dev);
985         /* Initialize new subchannel. */
986         spin_lock_irq(sch->lock);
987         cdev->private->schid = sch->schid;
988         cdev->ccwlock = sch->lock;
989         if (!sch_is_pseudo_sch(sch))
990                 sch_set_cdev(sch, cdev);
991         spin_unlock_irq(sch->lock);
992         if (!sch_is_pseudo_sch(sch))
993                 css_update_ssd_info(sch);
994         return 0;
995 }
996
997 static int ccw_device_move_to_orph(struct ccw_device *cdev)
998 {
999         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1000         struct channel_subsystem *css = to_css(sch->dev.parent);
1001
1002         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1003 }
1004
1005 static void io_subchannel_irq(struct subchannel *sch)
1006 {
1007         struct ccw_device *cdev;
1008
1009         cdev = sch_get_cdev(sch);
1010
1011         CIO_TRACE_EVENT(6, "IRQ");
1012         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1013         if (cdev)
1014                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1015         else
1016                 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
1017 }
1018
1019 void io_subchannel_init_config(struct subchannel *sch)
1020 {
1021         memset(&sch->config, 0, sizeof(sch->config));
1022         sch->config.csense = 1;
1023 }
1024
1025 static void io_subchannel_init_fields(struct subchannel *sch)
1026 {
1027         if (cio_is_console(sch->schid))
1028                 sch->opm = 0xff;
1029         else
1030                 sch->opm = chp_get_sch_opm(sch);
1031         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1032         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1033
1034         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1035                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1036                       sch->schib.pmcw.dev, sch->schid.ssid,
1037                       sch->schid.sch_no, sch->schib.pmcw.pim,
1038                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1039
1040         io_subchannel_init_config(sch);
1041 }
1042
1043 /*
1044  * Note: We always return 0 so that we bind to the device even on error.
1045  * This is needed so that our remove function is called on unregister.
1046  */
1047 static int io_subchannel_probe(struct subchannel *sch)
1048 {
1049         struct io_subchannel_private *io_priv;
1050         struct ccw_device *cdev;
1051         int rc;
1052
1053         if (cio_is_console(sch->schid)) {
1054                 rc = sysfs_create_group(&sch->dev.kobj,
1055                                         &io_subchannel_attr_group);
1056                 if (rc)
1057                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1058                                       "attributes for subchannel "
1059                                       "0.%x.%04x (rc=%d)\n",
1060                                       sch->schid.ssid, sch->schid.sch_no, rc);
1061                 /*
1062                  * The console subchannel already has an associated ccw_device.
1063                  * Throw the delayed uevent for the subchannel, register
1064                  * the ccw_device and exit.
1065                  */
1066                 dev_set_uevent_suppress(&sch->dev, 0);
1067                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1068                 cdev = sch_get_cdev(sch);
1069                 cdev->dev.groups = ccwdev_attr_groups;
1070                 device_initialize(&cdev->dev);
1071                 cdev->private->flags.initialized = 1;
1072                 ccw_device_register(cdev);
1073                 /*
1074                  * Check if the device is already online. If it is
1075                  * the reference count needs to be corrected since we
1076                  * didn't obtain a reference in ccw_device_set_online.
1077                  */
1078                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1079                     cdev->private->state != DEV_STATE_OFFLINE &&
1080                     cdev->private->state != DEV_STATE_BOXED)
1081                         get_device(&cdev->dev);
1082                 return 0;
1083         }
1084         io_subchannel_init_fields(sch);
1085         rc = cio_commit_config(sch);
1086         if (rc)
1087                 goto out_schedule;
1088         rc = sysfs_create_group(&sch->dev.kobj,
1089                                 &io_subchannel_attr_group);
1090         if (rc)
1091                 goto out_schedule;
1092         /* Allocate I/O subchannel private data. */
1093         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1094         if (!io_priv)
1095                 goto out_schedule;
1096
1097         set_io_private(sch, io_priv);
1098         css_schedule_eval(sch->schid);
1099         return 0;
1100
1101 out_schedule:
1102         spin_lock_irq(sch->lock);
1103         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1104         spin_unlock_irq(sch->lock);
1105         return 0;
1106 }
1107
1108 static int
1109 io_subchannel_remove (struct subchannel *sch)
1110 {
1111         struct io_subchannel_private *io_priv = to_io_private(sch);
1112         struct ccw_device *cdev;
1113
1114         cdev = sch_get_cdev(sch);
1115         if (!cdev)
1116                 goto out_free;
1117         io_subchannel_quiesce(sch);
1118         /* Set ccw device to not operational and drop reference. */
1119         spin_lock_irq(cdev->ccwlock);
1120         sch_set_cdev(sch, NULL);
1121         set_io_private(sch, NULL);
1122         cdev->private->state = DEV_STATE_NOT_OPER;
1123         spin_unlock_irq(cdev->ccwlock);
1124         ccw_device_unregister(cdev);
1125 out_free:
1126         kfree(io_priv);
1127         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1128         return 0;
1129 }
1130
1131 static void io_subchannel_verify(struct subchannel *sch)
1132 {
1133         struct ccw_device *cdev;
1134
1135         cdev = sch_get_cdev(sch);
1136         if (cdev)
1137                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1138 }
1139
1140 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1141 {
1142         struct ccw_device *cdev;
1143
1144         cdev = sch_get_cdev(sch);
1145         if (!cdev)
1146                 return;
1147         if (cio_update_schib(sch))
1148                 goto err;
1149         /* Check for I/O on path. */
1150         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1151                 goto out;
1152         if (cdev->private->state == DEV_STATE_ONLINE) {
1153                 ccw_device_kill_io(cdev);
1154                 goto out;
1155         }
1156         if (cio_clear(sch))
1157                 goto err;
1158 out:
1159         /* Trigger path verification. */
1160         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1161         return;
1162
1163 err:
1164         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1165 }
1166
1167 static int io_subchannel_chp_event(struct subchannel *sch,
1168                                    struct chp_link *link, int event)
1169 {
1170         struct ccw_device *cdev = sch_get_cdev(sch);
1171         int mask;
1172
1173         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1174         if (!mask)
1175                 return 0;
1176         switch (event) {
1177         case CHP_VARY_OFF:
1178                 sch->opm &= ~mask;
1179                 sch->lpm &= ~mask;
1180                 if (cdev)
1181                         cdev->private->path_gone_mask |= mask;
1182                 io_subchannel_terminate_path(sch, mask);
1183                 break;
1184         case CHP_VARY_ON:
1185                 sch->opm |= mask;
1186                 sch->lpm |= mask;
1187                 if (cdev)
1188                         cdev->private->path_new_mask |= mask;
1189                 io_subchannel_verify(sch);
1190                 break;
1191         case CHP_OFFLINE:
1192                 if (cio_update_schib(sch))
1193                         return -ENODEV;
1194                 if (cdev)
1195                         cdev->private->path_gone_mask |= mask;
1196                 io_subchannel_terminate_path(sch, mask);
1197                 break;
1198         case CHP_ONLINE:
1199                 if (cio_update_schib(sch))
1200                         return -ENODEV;
1201                 sch->lpm |= mask & sch->opm;
1202                 if (cdev)
1203                         cdev->private->path_new_mask |= mask;
1204                 io_subchannel_verify(sch);
1205                 break;
1206         }
1207         return 0;
1208 }
1209
1210 static void io_subchannel_quiesce(struct subchannel *sch)
1211 {
1212         struct ccw_device *cdev;
1213         int ret;
1214
1215         spin_lock_irq(sch->lock);
1216         cdev = sch_get_cdev(sch);
1217         if (cio_is_console(sch->schid))
1218                 goto out_unlock;
1219         if (!sch->schib.pmcw.ena)
1220                 goto out_unlock;
1221         ret = cio_disable_subchannel(sch);
1222         if (ret != -EBUSY)
1223                 goto out_unlock;
1224         if (cdev->handler)
1225                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1226         while (ret == -EBUSY) {
1227                 cdev->private->state = DEV_STATE_QUIESCE;
1228                 cdev->private->iretry = 255;
1229                 ret = ccw_device_cancel_halt_clear(cdev);
1230                 if (ret == -EBUSY) {
1231                         ccw_device_set_timeout(cdev, HZ/10);
1232                         spin_unlock_irq(sch->lock);
1233                         wait_event(cdev->private->wait_q,
1234                                    cdev->private->state != DEV_STATE_QUIESCE);
1235                         spin_lock_irq(sch->lock);
1236                 }
1237                 ret = cio_disable_subchannel(sch);
1238         }
1239 out_unlock:
1240         spin_unlock_irq(sch->lock);
1241 }
1242
1243 static void io_subchannel_shutdown(struct subchannel *sch)
1244 {
1245         io_subchannel_quiesce(sch);
1246 }
1247
1248 static int device_is_disconnected(struct ccw_device *cdev)
1249 {
1250         if (!cdev)
1251                 return 0;
1252         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1253                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1254 }
1255
1256 static int recovery_check(struct device *dev, void *data)
1257 {
1258         struct ccw_device *cdev = to_ccwdev(dev);
1259         int *redo = data;
1260
1261         spin_lock_irq(cdev->ccwlock);
1262         switch (cdev->private->state) {
1263         case DEV_STATE_DISCONNECTED:
1264                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1265                               cdev->private->dev_id.ssid,
1266                               cdev->private->dev_id.devno);
1267                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1268                 *redo = 1;
1269                 break;
1270         case DEV_STATE_DISCONNECTED_SENSE_ID:
1271                 *redo = 1;
1272                 break;
1273         }
1274         spin_unlock_irq(cdev->ccwlock);
1275
1276         return 0;
1277 }
1278
1279 static void recovery_work_func(struct work_struct *unused)
1280 {
1281         int redo = 0;
1282
1283         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1284         if (redo) {
1285                 spin_lock_irq(&recovery_lock);
1286                 if (!timer_pending(&recovery_timer)) {
1287                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1288                                 recovery_phase++;
1289                         mod_timer(&recovery_timer, jiffies +
1290                                   recovery_delay[recovery_phase] * HZ);
1291                 }
1292                 spin_unlock_irq(&recovery_lock);
1293         } else
1294                 CIO_MSG_EVENT(4, "recovery: end\n");
1295 }
1296
1297 static DECLARE_WORK(recovery_work, recovery_work_func);
1298
1299 static void recovery_func(unsigned long data)
1300 {
1301         /*
1302          * We can't do our recovery in softirq context and it's not
1303          * performance critical, so we schedule it.
1304          */
1305         schedule_work(&recovery_work);
1306 }
1307
1308 static void ccw_device_schedule_recovery(void)
1309 {
1310         unsigned long flags;
1311
1312         CIO_MSG_EVENT(4, "recovery: schedule\n");
1313         spin_lock_irqsave(&recovery_lock, flags);
1314         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1315                 recovery_phase = 0;
1316                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1317         }
1318         spin_unlock_irqrestore(&recovery_lock, flags);
1319 }
1320
1321 static int purge_fn(struct device *dev, void *data)
1322 {
1323         struct ccw_device *cdev = to_ccwdev(dev);
1324         struct ccw_dev_id *id = &cdev->private->dev_id;
1325
1326         spin_lock_irq(cdev->ccwlock);
1327         if (is_blacklisted(id->ssid, id->devno) &&
1328             (cdev->private->state == DEV_STATE_OFFLINE) &&
1329             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1330                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1331                               id->devno);
1332                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1333                 atomic_set(&cdev->private->onoff, 0);
1334         }
1335         spin_unlock_irq(cdev->ccwlock);
1336         /* Abort loop in case of pending signal. */
1337         if (signal_pending(current))
1338                 return -EINTR;
1339
1340         return 0;
1341 }
1342
1343 /**
1344  * ccw_purge_blacklisted - purge unused, blacklisted devices
1345  *
1346  * Unregister all ccw devices that are offline and on the blacklist.
1347  */
1348 int ccw_purge_blacklisted(void)
1349 {
1350         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1351         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1352         return 0;
1353 }
1354
1355 void ccw_device_set_disconnected(struct ccw_device *cdev)
1356 {
1357         if (!cdev)
1358                 return;
1359         ccw_device_set_timeout(cdev, 0);
1360         cdev->private->flags.fake_irb = 0;
1361         cdev->private->state = DEV_STATE_DISCONNECTED;
1362         if (cdev->online)
1363                 ccw_device_schedule_recovery();
1364 }
1365
1366 void ccw_device_set_notoper(struct ccw_device *cdev)
1367 {
1368         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1369
1370         CIO_TRACE_EVENT(2, "notoper");
1371         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1372         ccw_device_set_timeout(cdev, 0);
1373         cio_disable_subchannel(sch);
1374         cdev->private->state = DEV_STATE_NOT_OPER;
1375 }
1376
1377 enum io_sch_action {
1378         IO_SCH_UNREG,
1379         IO_SCH_ORPH_UNREG,
1380         IO_SCH_ATTACH,
1381         IO_SCH_UNREG_ATTACH,
1382         IO_SCH_ORPH_ATTACH,
1383         IO_SCH_REPROBE,
1384         IO_SCH_VERIFY,
1385         IO_SCH_DISC,
1386         IO_SCH_NOP,
1387 };
1388
1389 static enum io_sch_action sch_get_action(struct subchannel *sch)
1390 {
1391         struct ccw_device *cdev;
1392
1393         cdev = sch_get_cdev(sch);
1394         if (cio_update_schib(sch)) {
1395                 /* Not operational. */
1396                 if (!cdev)
1397                         return IO_SCH_UNREG;
1398                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1399                         return IO_SCH_UNREG;
1400                 return IO_SCH_ORPH_UNREG;
1401         }
1402         /* Operational. */
1403         if (!cdev)
1404                 return IO_SCH_ATTACH;
1405         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1406                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1407                         return IO_SCH_UNREG_ATTACH;
1408                 return IO_SCH_ORPH_ATTACH;
1409         }
1410         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1411                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1412                         return IO_SCH_UNREG;
1413                 return IO_SCH_DISC;
1414         }
1415         if (device_is_disconnected(cdev))
1416                 return IO_SCH_REPROBE;
1417         if (cdev->online)
1418                 return IO_SCH_VERIFY;
1419         return IO_SCH_NOP;
1420 }
1421
1422 /**
1423  * io_subchannel_sch_event - process subchannel event
1424  * @sch: subchannel
1425  * @process: non-zero if function is called in process context
1426  *
1427  * An unspecified event occurred for this subchannel. Adjust data according
1428  * to the current operational state of the subchannel and device. Return
1429  * zero when the event has been handled sufficiently or -EAGAIN when this
1430  * function should be called again in process context.
1431  */
1432 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1433 {
1434         unsigned long flags;
1435         struct ccw_device *cdev;
1436         struct ccw_dev_id dev_id;
1437         enum io_sch_action action;
1438         int rc = -EAGAIN;
1439
1440         spin_lock_irqsave(sch->lock, flags);
1441         if (!device_is_registered(&sch->dev))
1442                 goto out_unlock;
1443         if (work_pending(&sch->todo_work))
1444                 goto out_unlock;
1445         cdev = sch_get_cdev(sch);
1446         if (cdev && work_pending(&cdev->private->todo_work))
1447                 goto out_unlock;
1448         action = sch_get_action(sch);
1449         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1450                       sch->schid.ssid, sch->schid.sch_no, process,
1451                       action);
1452         /* Perform immediate actions while holding the lock. */
1453         switch (action) {
1454         case IO_SCH_REPROBE:
1455                 /* Trigger device recognition. */
1456                 ccw_device_trigger_reprobe(cdev);
1457                 rc = 0;
1458                 goto out_unlock;
1459         case IO_SCH_VERIFY:
1460                 if (cdev->private->flags.resuming == 1) {
1461                         if (cio_enable_subchannel(sch, (u32)(addr_t)sch)) {
1462                                 ccw_device_set_notoper(cdev);
1463                                 break;
1464                         }
1465                 }
1466                 /* Trigger path verification. */
1467                 io_subchannel_verify(sch);
1468                 rc = 0;
1469                 goto out_unlock;
1470         case IO_SCH_DISC:
1471                 ccw_device_set_disconnected(cdev);
1472                 rc = 0;
1473                 goto out_unlock;
1474         case IO_SCH_ORPH_UNREG:
1475         case IO_SCH_ORPH_ATTACH:
1476                 ccw_device_set_disconnected(cdev);
1477                 break;
1478         case IO_SCH_UNREG_ATTACH:
1479         case IO_SCH_UNREG:
1480                 if (!cdev)
1481                         break;
1482                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1483                         /*
1484                          * Note: delayed work triggered by this event
1485                          * and repeated calls to sch_event are synchronized
1486                          * by the above check for work_pending(cdev).
1487                          */
1488                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1489                 } else
1490                         ccw_device_set_notoper(cdev);
1491                 break;
1492         case IO_SCH_NOP:
1493                 rc = 0;
1494                 goto out_unlock;
1495         default:
1496                 break;
1497         }
1498         spin_unlock_irqrestore(sch->lock, flags);
1499         /* All other actions require process context. */
1500         if (!process)
1501                 goto out;
1502         /* Handle attached ccw device. */
1503         switch (action) {
1504         case IO_SCH_ORPH_UNREG:
1505         case IO_SCH_ORPH_ATTACH:
1506                 /* Move ccw device to orphanage. */
1507                 rc = ccw_device_move_to_orph(cdev);
1508                 if (rc)
1509                         goto out;
1510                 break;
1511         case IO_SCH_UNREG_ATTACH:
1512                 if (cdev->private->flags.resuming) {
1513                         /* Device will be handled later. */
1514                         rc = 0;
1515                         goto out;
1516                 }
1517                 /* Unregister ccw device. */
1518                 ccw_device_unregister(cdev);
1519                 break;
1520         default:
1521                 break;
1522         }
1523         /* Handle subchannel. */
1524         switch (action) {
1525         case IO_SCH_ORPH_UNREG:
1526         case IO_SCH_UNREG:
1527                 if (!cdev || !cdev->private->flags.resuming)
1528                         css_sch_device_unregister(sch);
1529                 break;
1530         case IO_SCH_ORPH_ATTACH:
1531         case IO_SCH_UNREG_ATTACH:
1532         case IO_SCH_ATTACH:
1533                 dev_id.ssid = sch->schid.ssid;
1534                 dev_id.devno = sch->schib.pmcw.dev;
1535                 cdev = get_ccwdev_by_dev_id(&dev_id);
1536                 if (!cdev) {
1537                         sch_create_and_recog_new_device(sch);
1538                         break;
1539                 }
1540                 rc = ccw_device_move_to_sch(cdev, sch);
1541                 if (rc) {
1542                         /* Release reference from get_ccwdev_by_dev_id() */
1543                         put_device(&cdev->dev);
1544                         goto out;
1545                 }
1546                 spin_lock_irqsave(sch->lock, flags);
1547                 ccw_device_trigger_reprobe(cdev);
1548                 spin_unlock_irqrestore(sch->lock, flags);
1549                 /* Release reference from get_ccwdev_by_dev_id() */
1550                 put_device(&cdev->dev);
1551                 break;
1552         default:
1553                 break;
1554         }
1555         return 0;
1556
1557 out_unlock:
1558         spin_unlock_irqrestore(sch->lock, flags);
1559 out:
1560         return rc;
1561 }
1562
1563 #ifdef CONFIG_CCW_CONSOLE
1564 static struct ccw_device console_cdev;
1565 static struct ccw_device_private console_private;
1566 static int console_cdev_in_use;
1567
1568 static DEFINE_SPINLOCK(ccw_console_lock);
1569
1570 spinlock_t * cio_get_console_lock(void)
1571 {
1572         return &ccw_console_lock;
1573 }
1574
1575 static int ccw_device_console_enable(struct ccw_device *cdev,
1576                                      struct subchannel *sch)
1577 {
1578         struct io_subchannel_private *io_priv = cio_get_console_priv();
1579         int rc;
1580
1581         /* Attach subchannel private data. */
1582         memset(io_priv, 0, sizeof(*io_priv));
1583         set_io_private(sch, io_priv);
1584         io_subchannel_init_fields(sch);
1585         rc = cio_commit_config(sch);
1586         if (rc)
1587                 return rc;
1588         sch->driver = &io_subchannel_driver;
1589         /* Initialize the ccw_device structure. */
1590         cdev->dev.parent= &sch->dev;
1591         sch_set_cdev(sch, cdev);
1592         io_subchannel_recog(cdev, sch);
1593         /* Now wait for the async. recognition to come to an end. */
1594         spin_lock_irq(cdev->ccwlock);
1595         while (!dev_fsm_final_state(cdev))
1596                 wait_cons_dev();
1597         rc = -EIO;
1598         if (cdev->private->state != DEV_STATE_OFFLINE)
1599                 goto out_unlock;
1600         ccw_device_online(cdev);
1601         while (!dev_fsm_final_state(cdev))
1602                 wait_cons_dev();
1603         if (cdev->private->state != DEV_STATE_ONLINE)
1604                 goto out_unlock;
1605         rc = 0;
1606 out_unlock:
1607         spin_unlock_irq(cdev->ccwlock);
1608         return rc;
1609 }
1610
1611 struct ccw_device *
1612 ccw_device_probe_console(void)
1613 {
1614         struct subchannel *sch;
1615         int ret;
1616
1617         if (xchg(&console_cdev_in_use, 1) != 0)
1618                 return ERR_PTR(-EBUSY);
1619         sch = cio_probe_console();
1620         if (IS_ERR(sch)) {
1621                 console_cdev_in_use = 0;
1622                 return (void *) sch;
1623         }
1624         memset(&console_cdev, 0, sizeof(struct ccw_device));
1625         memset(&console_private, 0, sizeof(struct ccw_device_private));
1626         console_cdev.private = &console_private;
1627         console_private.cdev = &console_cdev;
1628         console_private.int_class = IOINT_CIO;
1629         ret = ccw_device_console_enable(&console_cdev, sch);
1630         if (ret) {
1631                 cio_release_console();
1632                 console_cdev_in_use = 0;
1633                 return ERR_PTR(ret);
1634         }
1635         console_cdev.online = 1;
1636         return &console_cdev;
1637 }
1638
1639 static int ccw_device_pm_restore(struct device *dev);
1640
1641 int ccw_device_force_console(void)
1642 {
1643         if (!console_cdev_in_use)
1644                 return -ENODEV;
1645         return ccw_device_pm_restore(&console_cdev.dev);
1646 }
1647 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1648 #endif
1649
1650 /*
1651  * get ccw_device matching the busid, but only if owned by cdrv
1652  */
1653 static int
1654 __ccwdev_check_busid(struct device *dev, void *id)
1655 {
1656         char *bus_id;
1657
1658         bus_id = id;
1659
1660         return (strcmp(bus_id, dev_name(dev)) == 0);
1661 }
1662
1663
1664 /**
1665  * get_ccwdev_by_busid() - obtain device from a bus id
1666  * @cdrv: driver the device is owned by
1667  * @bus_id: bus id of the device to be searched
1668  *
1669  * This function searches all devices owned by @cdrv for a device with a bus
1670  * id matching @bus_id.
1671  * Returns:
1672  *  If a match is found, its reference count of the found device is increased
1673  *  and it is returned; else %NULL is returned.
1674  */
1675 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1676                                        const char *bus_id)
1677 {
1678         struct device *dev;
1679
1680         dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1681                                  __ccwdev_check_busid);
1682
1683         return dev ? to_ccwdev(dev) : NULL;
1684 }
1685
1686 /************************** device driver handling ************************/
1687
1688 /* This is the implementation of the ccw_driver class. The probe, remove
1689  * and release methods are initially very similar to the device_driver
1690  * implementations, with the difference that they have ccw_device
1691  * arguments.
1692  *
1693  * A ccw driver also contains the information that is needed for
1694  * device matching.
1695  */
1696 static int
1697 ccw_device_probe (struct device *dev)
1698 {
1699         struct ccw_device *cdev = to_ccwdev(dev);
1700         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1701         int ret;
1702
1703         cdev->drv = cdrv; /* to let the driver call _set_online */
1704         /* Note: we interpret class 0 in this context as an uninitialized
1705          * field since it translates to a non-I/O interrupt class. */
1706         if (cdrv->int_class != 0)
1707                 cdev->private->int_class = cdrv->int_class;
1708         else
1709                 cdev->private->int_class = IOINT_CIO;
1710
1711         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1712
1713         if (ret) {
1714                 cdev->drv = NULL;
1715                 cdev->private->int_class = IOINT_CIO;
1716                 return ret;
1717         }
1718
1719         return 0;
1720 }
1721
1722 static int
1723 ccw_device_remove (struct device *dev)
1724 {
1725         struct ccw_device *cdev = to_ccwdev(dev);
1726         struct ccw_driver *cdrv = cdev->drv;
1727         int ret;
1728
1729         if (cdrv->remove)
1730                 cdrv->remove(cdev);
1731         if (cdev->online) {
1732                 cdev->online = 0;
1733                 spin_lock_irq(cdev->ccwlock);
1734                 ret = ccw_device_offline(cdev);
1735                 spin_unlock_irq(cdev->ccwlock);
1736                 if (ret == 0)
1737                         wait_event(cdev->private->wait_q,
1738                                    dev_fsm_final_state(cdev));
1739                 else
1740                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1741                                       "device 0.%x.%04x\n",
1742                                       ret, cdev->private->dev_id.ssid,
1743                                       cdev->private->dev_id.devno);
1744                 /* Give up reference obtained in ccw_device_set_online(). */
1745                 put_device(&cdev->dev);
1746         }
1747         ccw_device_set_timeout(cdev, 0);
1748         cdev->drv = NULL;
1749         cdev->private->int_class = IOINT_CIO;
1750         return 0;
1751 }
1752
1753 static void ccw_device_shutdown(struct device *dev)
1754 {
1755         struct ccw_device *cdev;
1756
1757         cdev = to_ccwdev(dev);
1758         if (cdev->drv && cdev->drv->shutdown)
1759                 cdev->drv->shutdown(cdev);
1760         disable_cmf(cdev);
1761 }
1762
1763 static int ccw_device_pm_prepare(struct device *dev)
1764 {
1765         struct ccw_device *cdev = to_ccwdev(dev);
1766
1767         if (work_pending(&cdev->private->todo_work))
1768                 return -EAGAIN;
1769         /* Fail while device is being set online/offline. */
1770         if (atomic_read(&cdev->private->onoff))
1771                 return -EAGAIN;
1772
1773         if (cdev->online && cdev->drv && cdev->drv->prepare)
1774                 return cdev->drv->prepare(cdev);
1775
1776         return 0;
1777 }
1778
1779 static void ccw_device_pm_complete(struct device *dev)
1780 {
1781         struct ccw_device *cdev = to_ccwdev(dev);
1782
1783         if (cdev->online && cdev->drv && cdev->drv->complete)
1784                 cdev->drv->complete(cdev);
1785 }
1786
1787 static int ccw_device_pm_freeze(struct device *dev)
1788 {
1789         struct ccw_device *cdev = to_ccwdev(dev);
1790         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1791         int ret, cm_enabled;
1792
1793         /* Fail suspend while device is in transistional state. */
1794         if (!dev_fsm_final_state(cdev))
1795                 return -EAGAIN;
1796         if (!cdev->online)
1797                 return 0;
1798         if (cdev->drv && cdev->drv->freeze) {
1799                 ret = cdev->drv->freeze(cdev);
1800                 if (ret)
1801                         return ret;
1802         }
1803
1804         spin_lock_irq(sch->lock);
1805         cm_enabled = cdev->private->cmb != NULL;
1806         spin_unlock_irq(sch->lock);
1807         if (cm_enabled) {
1808                 /* Don't have the css write on memory. */
1809                 ret = ccw_set_cmf(cdev, 0);
1810                 if (ret)
1811                         return ret;
1812         }
1813         /* From here on, disallow device driver I/O. */
1814         spin_lock_irq(sch->lock);
1815         ret = cio_disable_subchannel(sch);
1816         spin_unlock_irq(sch->lock);
1817
1818         return ret;
1819 }
1820
1821 static int ccw_device_pm_thaw(struct device *dev)
1822 {
1823         struct ccw_device *cdev = to_ccwdev(dev);
1824         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1825         int ret, cm_enabled;
1826
1827         if (!cdev->online)
1828                 return 0;
1829
1830         spin_lock_irq(sch->lock);
1831         /* Allow device driver I/O again. */
1832         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1833         cm_enabled = cdev->private->cmb != NULL;
1834         spin_unlock_irq(sch->lock);
1835         if (ret)
1836                 return ret;
1837
1838         if (cm_enabled) {
1839                 ret = ccw_set_cmf(cdev, 1);
1840                 if (ret)
1841                         return ret;
1842         }
1843
1844         if (cdev->drv && cdev->drv->thaw)
1845                 ret = cdev->drv->thaw(cdev);
1846
1847         return ret;
1848 }
1849
1850 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1851 {
1852         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1853
1854         spin_lock_irq(sch->lock);
1855         if (cio_is_console(sch->schid)) {
1856                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1857                 goto out_unlock;
1858         }
1859         /*
1860          * While we were sleeping, devices may have gone or become
1861          * available again. Kick re-detection.
1862          */
1863         cdev->private->flags.resuming = 1;
1864         cdev->private->path_new_mask = LPM_ANYPATH;
1865         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1866         spin_unlock_irq(sch->lock);
1867         css_wait_for_slow_path();
1868
1869         /* cdev may have been moved to a different subchannel. */
1870         sch = to_subchannel(cdev->dev.parent);
1871         spin_lock_irq(sch->lock);
1872         if (cdev->private->state != DEV_STATE_ONLINE &&
1873             cdev->private->state != DEV_STATE_OFFLINE)
1874                 goto out_unlock;
1875
1876         ccw_device_recognition(cdev);
1877         spin_unlock_irq(sch->lock);
1878         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1879                    cdev->private->state == DEV_STATE_DISCONNECTED);
1880         spin_lock_irq(sch->lock);
1881
1882 out_unlock:
1883         cdev->private->flags.resuming = 0;
1884         spin_unlock_irq(sch->lock);
1885 }
1886
1887 static int resume_handle_boxed(struct ccw_device *cdev)
1888 {
1889         cdev->private->state = DEV_STATE_BOXED;
1890         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1891                 return 0;
1892         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1893         return -ENODEV;
1894 }
1895
1896 static int resume_handle_disc(struct ccw_device *cdev)
1897 {
1898         cdev->private->state = DEV_STATE_DISCONNECTED;
1899         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1900                 return 0;
1901         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1902         return -ENODEV;
1903 }
1904
1905 static int ccw_device_pm_restore(struct device *dev)
1906 {
1907         struct ccw_device *cdev = to_ccwdev(dev);
1908         struct subchannel *sch;
1909         int ret = 0;
1910
1911         __ccw_device_pm_restore(cdev);
1912         sch = to_subchannel(cdev->dev.parent);
1913         spin_lock_irq(sch->lock);
1914         if (cio_is_console(sch->schid))
1915                 goto out_restore;
1916
1917         /* check recognition results */
1918         switch (cdev->private->state) {
1919         case DEV_STATE_OFFLINE:
1920         case DEV_STATE_ONLINE:
1921                 cdev->private->flags.donotify = 0;
1922                 break;
1923         case DEV_STATE_BOXED:
1924                 ret = resume_handle_boxed(cdev);
1925                 if (ret)
1926                         goto out_unlock;
1927                 goto out_restore;
1928         default:
1929                 ret = resume_handle_disc(cdev);
1930                 if (ret)
1931                         goto out_unlock;
1932                 goto out_restore;
1933         }
1934         /* check if the device type has changed */
1935         if (!ccw_device_test_sense_data(cdev)) {
1936                 ccw_device_update_sense_data(cdev);
1937                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1938                 ret = -ENODEV;
1939                 goto out_unlock;
1940         }
1941         if (!cdev->online)
1942                 goto out_unlock;
1943
1944         if (ccw_device_online(cdev)) {
1945                 ret = resume_handle_disc(cdev);
1946                 if (ret)
1947                         goto out_unlock;
1948                 goto out_restore;
1949         }
1950         spin_unlock_irq(sch->lock);
1951         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1952         spin_lock_irq(sch->lock);
1953
1954         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1955                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1956                 ret = -ENODEV;
1957                 goto out_unlock;
1958         }
1959
1960         /* reenable cmf, if needed */
1961         if (cdev->private->cmb) {
1962                 spin_unlock_irq(sch->lock);
1963                 ret = ccw_set_cmf(cdev, 1);
1964                 spin_lock_irq(sch->lock);
1965                 if (ret) {
1966                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1967                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
1968                                       cdev->private->dev_id.devno, ret);
1969                         ret = 0;
1970                 }
1971         }
1972
1973 out_restore:
1974         spin_unlock_irq(sch->lock);
1975         if (cdev->online && cdev->drv && cdev->drv->restore)
1976                 ret = cdev->drv->restore(cdev);
1977         return ret;
1978
1979 out_unlock:
1980         spin_unlock_irq(sch->lock);
1981         return ret;
1982 }
1983
1984 static const struct dev_pm_ops ccw_pm_ops = {
1985         .prepare = ccw_device_pm_prepare,
1986         .complete = ccw_device_pm_complete,
1987         .freeze = ccw_device_pm_freeze,
1988         .thaw = ccw_device_pm_thaw,
1989         .restore = ccw_device_pm_restore,
1990 };
1991
1992 static struct bus_type ccw_bus_type = {
1993         .name   = "ccw",
1994         .match  = ccw_bus_match,
1995         .uevent = ccw_uevent,
1996         .probe  = ccw_device_probe,
1997         .remove = ccw_device_remove,
1998         .shutdown = ccw_device_shutdown,
1999         .pm = &ccw_pm_ops,
2000 };
2001
2002 /**
2003  * ccw_driver_register() - register a ccw driver
2004  * @cdriver: driver to be registered
2005  *
2006  * This function is mainly a wrapper around driver_register().
2007  * Returns:
2008  *   %0 on success and a negative error value on failure.
2009  */
2010 int ccw_driver_register(struct ccw_driver *cdriver)
2011 {
2012         struct device_driver *drv = &cdriver->driver;
2013
2014         drv->bus = &ccw_bus_type;
2015
2016         return driver_register(drv);
2017 }
2018
2019 /**
2020  * ccw_driver_unregister() - deregister a ccw driver
2021  * @cdriver: driver to be deregistered
2022  *
2023  * This function is mainly a wrapper around driver_unregister().
2024  */
2025 void ccw_driver_unregister(struct ccw_driver *cdriver)
2026 {
2027         driver_unregister(&cdriver->driver);
2028 }
2029
2030 /* Helper func for qdio. */
2031 struct subchannel_id
2032 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2033 {
2034         struct subchannel *sch;
2035
2036         sch = to_subchannel(cdev->dev.parent);
2037         return sch->schid;
2038 }
2039
2040 static void ccw_device_todo(struct work_struct *work)
2041 {
2042         struct ccw_device_private *priv;
2043         struct ccw_device *cdev;
2044         struct subchannel *sch;
2045         enum cdev_todo todo;
2046
2047         priv = container_of(work, struct ccw_device_private, todo_work);
2048         cdev = priv->cdev;
2049         sch = to_subchannel(cdev->dev.parent);
2050         /* Find out todo. */
2051         spin_lock_irq(cdev->ccwlock);
2052         todo = priv->todo;
2053         priv->todo = CDEV_TODO_NOTHING;
2054         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2055                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2056         spin_unlock_irq(cdev->ccwlock);
2057         /* Perform todo. */
2058         switch (todo) {
2059         case CDEV_TODO_ENABLE_CMF:
2060                 cmf_reenable(cdev);
2061                 break;
2062         case CDEV_TODO_REBIND:
2063                 ccw_device_do_unbind_bind(cdev);
2064                 break;
2065         case CDEV_TODO_REGISTER:
2066                 io_subchannel_register(cdev);
2067                 break;
2068         case CDEV_TODO_UNREG_EVAL:
2069                 if (!sch_is_pseudo_sch(sch))
2070                         css_schedule_eval(sch->schid);
2071                 /* fall-through */
2072         case CDEV_TODO_UNREG:
2073                 if (sch_is_pseudo_sch(sch))
2074                         ccw_device_unregister(cdev);
2075                 else
2076                         ccw_device_call_sch_unregister(cdev);
2077                 break;
2078         default:
2079                 break;
2080         }
2081         /* Release workqueue ref. */
2082         put_device(&cdev->dev);
2083 }
2084
2085 /**
2086  * ccw_device_sched_todo - schedule ccw device operation
2087  * @cdev: ccw device
2088  * @todo: todo
2089  *
2090  * Schedule the operation identified by @todo to be performed on the slow path
2091  * workqueue. Do nothing if another operation with higher priority is already
2092  * scheduled. Needs to be called with ccwdev lock held.
2093  */
2094 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2095 {
2096         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2097                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2098                       todo);
2099         if (cdev->private->todo >= todo)
2100                 return;
2101         cdev->private->todo = todo;
2102         /* Get workqueue ref. */
2103         if (!get_device(&cdev->dev))
2104                 return;
2105         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2106                 /* Already queued, release workqueue ref. */
2107                 put_device(&cdev->dev);
2108         }
2109 }
2110
2111 /**
2112  * ccw_device_siosl() - initiate logging
2113  * @cdev: ccw device
2114  *
2115  * This function is used to invoke model-dependent logging within the channel
2116  * subsystem.
2117  */
2118 int ccw_device_siosl(struct ccw_device *cdev)
2119 {
2120         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2121
2122         return chsc_siosl(sch->schid);
2123 }
2124 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2125
2126 MODULE_LICENSE("GPL");
2127 EXPORT_SYMBOL(ccw_device_set_online);
2128 EXPORT_SYMBOL(ccw_device_set_offline);
2129 EXPORT_SYMBOL(ccw_driver_register);
2130 EXPORT_SYMBOL(ccw_driver_unregister);
2131 EXPORT_SYMBOL(get_ccwdev_by_busid);
2132 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);