[S390] cio: Make ccw_device_register() static.
[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 (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 "css.h"
27 #include "device.h"
28 #include "ioasm.h"
29
30 /******************* bus type handling ***********************/
31
32 /* The Linux driver model distinguishes between a bus type and
33  * the bus itself. Of course we only have one channel
34  * subsystem driver and one channel system per machine, but
35  * we still use the abstraction. T.R. says it's a good idea. */
36 static int
37 ccw_bus_match (struct device * dev, struct device_driver * drv)
38 {
39         struct ccw_device *cdev = to_ccwdev(dev);
40         struct ccw_driver *cdrv = to_ccwdrv(drv);
41         const struct ccw_device_id *ids = cdrv->ids, *found;
42
43         if (!ids)
44                 return 0;
45
46         found = ccw_device_id_match(ids, &cdev->id);
47         if (!found)
48                 return 0;
49
50         cdev->id.driver_info = found->driver_info;
51
52         return 1;
53 }
54
55 /* Store modalias string delimited by prefix/suffix string into buffer with
56  * specified size. Return length of resulting string (excluding trailing '\0')
57  * even if string doesn't fit buffer (snprintf semantics). */
58 static int snprint_alias(char *buf, size_t size, const char *prefix,
59                          struct ccw_device_id *id, const char *suffix)
60 {
61         int len;
62
63         len = snprintf(buf, size, "%sccw:t%04Xm%02X", prefix, id->cu_type,
64                        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;
88
89         /* CU_TYPE= */
90         len = snprintf(buffer, buffer_size, "CU_TYPE=%04X", id->cu_type) + 1;
91         if (len > buffer_size || i >= num_envp)
92                 return -ENOMEM;
93         envp[i++] = buffer;
94         buffer += len;
95         buffer_size -= len;
96
97         /* CU_MODEL= */
98         len = snprintf(buffer, buffer_size, "CU_MODEL=%02X", id->cu_model) + 1;
99         if (len > buffer_size || i >= num_envp)
100                 return -ENOMEM;
101         envp[i++] = buffer;
102         buffer += len;
103         buffer_size -= len;
104
105         /* The next two can be zero, that's ok for us */
106         /* DEV_TYPE= */
107         len = snprintf(buffer, buffer_size, "DEV_TYPE=%04X", id->dev_type) + 1;
108         if (len > buffer_size || i >= num_envp)
109                 return -ENOMEM;
110         envp[i++] = buffer;
111         buffer += len;
112         buffer_size -= len;
113
114         /* DEV_MODEL= */
115         len = snprintf(buffer, buffer_size, "DEV_MODEL=%02X",
116                         (unsigned char) id->dev_model) + 1;
117         if (len > buffer_size || i >= num_envp)
118                 return -ENOMEM;
119         envp[i++] = buffer;
120         buffer += len;
121         buffer_size -= len;
122
123         /* MODALIAS=  */
124         len = snprint_alias(buffer, buffer_size, "MODALIAS=", id, "") + 1;
125         if (len > buffer_size || i >= num_envp)
126                 return -ENOMEM;
127         envp[i++] = buffer;
128         buffer += len;
129         buffer_size -= len;
130
131         envp[i] = NULL;
132
133         return 0;
134 }
135
136 struct bus_type ccw_bus_type;
137
138 static int io_subchannel_probe (struct subchannel *);
139 static int io_subchannel_remove (struct subchannel *);
140 void io_subchannel_irq (struct device *);
141 static int io_subchannel_notify(struct device *, int);
142 static void io_subchannel_verify(struct device *);
143 static void io_subchannel_ioterm(struct device *);
144 static void io_subchannel_shutdown(struct subchannel *);
145
146 struct css_driver io_subchannel_driver = {
147         .subchannel_type = SUBCHANNEL_TYPE_IO,
148         .drv = {
149                 .name = "io_subchannel",
150                 .bus  = &css_bus_type,
151         },
152         .irq = io_subchannel_irq,
153         .notify = io_subchannel_notify,
154         .verify = io_subchannel_verify,
155         .termination = io_subchannel_ioterm,
156         .probe = io_subchannel_probe,
157         .remove = io_subchannel_remove,
158         .shutdown = io_subchannel_shutdown,
159 };
160
161 struct workqueue_struct *ccw_device_work;
162 struct workqueue_struct *ccw_device_notify_work;
163 wait_queue_head_t ccw_device_init_wq;
164 atomic_t ccw_device_init_count;
165
166 static int __init
167 init_ccw_bus_type (void)
168 {
169         int ret;
170
171         init_waitqueue_head(&ccw_device_init_wq);
172         atomic_set(&ccw_device_init_count, 0);
173
174         ccw_device_work = create_singlethread_workqueue("cio");
175         if (!ccw_device_work)
176                 return -ENOMEM; /* FIXME: better errno ? */
177         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
178         if (!ccw_device_notify_work) {
179                 ret = -ENOMEM; /* FIXME: better errno ? */
180                 goto out_err;
181         }
182         slow_path_wq = create_singlethread_workqueue("kslowcrw");
183         if (!slow_path_wq) {
184                 ret = -ENOMEM; /* FIXME: better errno ? */
185                 goto out_err;
186         }
187         if ((ret = bus_register (&ccw_bus_type)))
188                 goto out_err;
189
190         if ((ret = driver_register(&io_subchannel_driver.drv)))
191                 goto out_err;
192
193         wait_event(ccw_device_init_wq,
194                    atomic_read(&ccw_device_init_count) == 0);
195         flush_workqueue(ccw_device_work);
196         return 0;
197 out_err:
198         if (ccw_device_work)
199                 destroy_workqueue(ccw_device_work);
200         if (ccw_device_notify_work)
201                 destroy_workqueue(ccw_device_notify_work);
202         if (slow_path_wq)
203                 destroy_workqueue(slow_path_wq);
204         return ret;
205 }
206
207 static void __exit
208 cleanup_ccw_bus_type (void)
209 {
210         driver_unregister(&io_subchannel_driver.drv);
211         bus_unregister(&ccw_bus_type);
212         destroy_workqueue(ccw_device_notify_work);
213         destroy_workqueue(ccw_device_work);
214 }
215
216 subsys_initcall(init_ccw_bus_type);
217 module_exit(cleanup_ccw_bus_type);
218
219 /************************ device handling **************************/
220
221 /*
222  * A ccw_device has some interfaces in sysfs in addition to the
223  * standard ones.
224  * The following entries are designed to export the information which
225  * resided in 2.4 in /proc/subchannels. Subchannel and device number
226  * are obvious, so they don't have an entry :)
227  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
228  */
229 static ssize_t
230 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
231 {
232         struct subchannel *sch = to_subchannel(dev);
233         struct ssd_info *ssd = &sch->ssd_info;
234         ssize_t ret = 0;
235         int chp;
236
237         for (chp = 0; chp < 8; chp++)
238                 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
239
240         ret += sprintf (buf+ret, "\n");
241         return min((ssize_t)PAGE_SIZE, ret);
242 }
243
244 static ssize_t
245 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
246 {
247         struct subchannel *sch = to_subchannel(dev);
248         struct pmcw *pmcw = &sch->schib.pmcw;
249
250         return sprintf (buf, "%02x %02x %02x\n",
251                         pmcw->pim, pmcw->pam, pmcw->pom);
252 }
253
254 static ssize_t
255 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
256 {
257         struct ccw_device *cdev = to_ccwdev(dev);
258         struct ccw_device_id *id = &(cdev->id);
259
260         if (id->dev_type != 0)
261                 return sprintf(buf, "%04x/%02x\n",
262                                 id->dev_type, id->dev_model);
263         else
264                 return sprintf(buf, "n/a\n");
265 }
266
267 static ssize_t
268 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
269 {
270         struct ccw_device *cdev = to_ccwdev(dev);
271         struct ccw_device_id *id = &(cdev->id);
272
273         return sprintf(buf, "%04x/%02x\n",
274                        id->cu_type, id->cu_model);
275 }
276
277 static ssize_t
278 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
279 {
280         struct ccw_device *cdev = to_ccwdev(dev);
281         struct ccw_device_id *id = &(cdev->id);
282         int len;
283
284         len = snprint_alias(buf, PAGE_SIZE, "", id, "\n") + 1;
285
286         return len > PAGE_SIZE ? PAGE_SIZE : len;
287 }
288
289 static ssize_t
290 online_show (struct device *dev, struct device_attribute *attr, char *buf)
291 {
292         struct ccw_device *cdev = to_ccwdev(dev);
293
294         return sprintf(buf, cdev->online ? "1\n" : "0\n");
295 }
296
297 static void
298 ccw_device_remove_disconnected(struct ccw_device *cdev)
299 {
300         struct subchannel *sch;
301         /*
302          * Forced offline in disconnected state means
303          * 'throw away device'.
304          */
305         sch = to_subchannel(cdev->dev.parent);
306         css_sch_device_unregister(sch);
307         /* Reset intparm to zeroes. */
308         sch->schib.pmcw.intparm = 0;
309         cio_modify(sch);
310         put_device(&sch->dev);
311 }
312
313 int
314 ccw_device_set_offline(struct ccw_device *cdev)
315 {
316         int ret;
317
318         if (!cdev)
319                 return -ENODEV;
320         if (!cdev->online || !cdev->drv)
321                 return -EINVAL;
322
323         if (cdev->drv->set_offline) {
324                 ret = cdev->drv->set_offline(cdev);
325                 if (ret != 0)
326                         return ret;
327         }
328         cdev->online = 0;
329         spin_lock_irq(cdev->ccwlock);
330         ret = ccw_device_offline(cdev);
331         if (ret == -ENODEV) {
332                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
333                         cdev->private->state = DEV_STATE_OFFLINE;
334                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
335                 }
336                 spin_unlock_irq(cdev->ccwlock);
337                 return ret;
338         }
339         spin_unlock_irq(cdev->ccwlock);
340         if (ret == 0)
341                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
342         else {
343                 pr_debug("ccw_device_offline returned %d, device %s\n",
344                          ret, cdev->dev.bus_id);
345                 cdev->online = 1;
346         }
347         return ret;
348 }
349
350 int
351 ccw_device_set_online(struct ccw_device *cdev)
352 {
353         int ret;
354
355         if (!cdev)
356                 return -ENODEV;
357         if (cdev->online || !cdev->drv)
358                 return -EINVAL;
359
360         spin_lock_irq(cdev->ccwlock);
361         ret = ccw_device_online(cdev);
362         spin_unlock_irq(cdev->ccwlock);
363         if (ret == 0)
364                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
365         else {
366                 pr_debug("ccw_device_online returned %d, device %s\n",
367                          ret, cdev->dev.bus_id);
368                 return ret;
369         }
370         if (cdev->private->state != DEV_STATE_ONLINE)
371                 return -ENODEV;
372         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
373                 cdev->online = 1;
374                 return 0;
375         }
376         spin_lock_irq(cdev->ccwlock);
377         ret = ccw_device_offline(cdev);
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         return (ret == 0) ? -ENODEV : ret;
385 }
386
387 static ssize_t
388 online_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
389 {
390         struct ccw_device *cdev = to_ccwdev(dev);
391         int i, force, ret;
392         char *tmp;
393
394         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
395                 return -EAGAIN;
396
397         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
398                 atomic_set(&cdev->private->onoff, 0);
399                 return -EINVAL;
400         }
401         if (!strncmp(buf, "force\n", count)) {
402                 force = 1;
403                 i = 1;
404         } else {
405                 force = 0;
406                 i = simple_strtoul(buf, &tmp, 16);
407         }
408         if (i == 1) {
409                 /* Do device recognition, if needed. */
410                 if (cdev->id.cu_type == 0) {
411                         ret = ccw_device_recognition(cdev);
412                         if (ret) {
413                                 printk(KERN_WARNING"Couldn't start recognition "
414                                        "for device %s (ret=%d)\n",
415                                        cdev->dev.bus_id, ret);
416                                 goto out;
417                         }
418                         wait_event(cdev->private->wait_q,
419                                    cdev->private->flags.recog_done);
420                 }
421                 if (cdev->drv && cdev->drv->set_online)
422                         ccw_device_set_online(cdev);
423         } else if (i == 0) {
424                 if (cdev->private->state == DEV_STATE_DISCONNECTED)
425                         ccw_device_remove_disconnected(cdev);
426                 else if (cdev->drv && cdev->drv->set_offline)
427                         ccw_device_set_offline(cdev);
428         }
429         if (force && cdev->private->state == DEV_STATE_BOXED) {
430                 ret = ccw_device_stlck(cdev);
431                 if (ret) {
432                         printk(KERN_WARNING"ccw_device_stlck for device %s "
433                                "returned %d!\n", cdev->dev.bus_id, ret);
434                         goto out;
435                 }
436                 /* Do device recognition, if needed. */
437                 if (cdev->id.cu_type == 0) {
438                         cdev->private->state = DEV_STATE_NOT_OPER;
439                         ret = ccw_device_recognition(cdev);
440                         if (ret) {
441                                 printk(KERN_WARNING"Couldn't start recognition "
442                                        "for device %s (ret=%d)\n",
443                                        cdev->dev.bus_id, ret);
444                                 goto out;
445                         }
446                         wait_event(cdev->private->wait_q,
447                                    cdev->private->flags.recog_done);
448                 }
449                 if (cdev->drv && cdev->drv->set_online)
450                         ccw_device_set_online(cdev);
451         }
452         out:
453         if (cdev->drv)
454                 module_put(cdev->drv->owner);
455         atomic_set(&cdev->private->onoff, 0);
456         return count;
457 }
458
459 static ssize_t
460 available_show (struct device *dev, struct device_attribute *attr, char *buf)
461 {
462         struct ccw_device *cdev = to_ccwdev(dev);
463         struct subchannel *sch;
464
465         switch (cdev->private->state) {
466         case DEV_STATE_BOXED:
467                 return sprintf(buf, "boxed\n");
468         case DEV_STATE_DISCONNECTED:
469         case DEV_STATE_DISCONNECTED_SENSE_ID:
470         case DEV_STATE_NOT_OPER:
471                 sch = to_subchannel(dev->parent);
472                 if (!sch->lpm)
473                         return sprintf(buf, "no path\n");
474                 else
475                         return sprintf(buf, "no device\n");
476         default:
477                 /* All other states considered fine. */
478                 return sprintf(buf, "good\n");
479         }
480 }
481
482 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
483 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
484 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
485 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
486 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
487 static DEVICE_ATTR(online, 0644, online_show, online_store);
488 extern struct device_attribute dev_attr_cmb_enable;
489 static DEVICE_ATTR(availability, 0444, available_show, NULL);
490
491 static struct attribute * subch_attrs[] = {
492         &dev_attr_chpids.attr,
493         &dev_attr_pimpampom.attr,
494         NULL,
495 };
496
497 static struct attribute_group subch_attr_group = {
498         .attrs = subch_attrs,
499 };
500
501 static inline int
502 subchannel_add_files (struct device *dev)
503 {
504         return sysfs_create_group(&dev->kobj, &subch_attr_group);
505 }
506
507 static struct attribute * ccwdev_attrs[] = {
508         &dev_attr_devtype.attr,
509         &dev_attr_cutype.attr,
510         &dev_attr_modalias.attr,
511         &dev_attr_online.attr,
512         &dev_attr_cmb_enable.attr,
513         &dev_attr_availability.attr,
514         NULL,
515 };
516
517 static struct attribute_group ccwdev_attr_group = {
518         .attrs = ccwdev_attrs,
519 };
520
521 static inline int
522 device_add_files (struct device *dev)
523 {
524         return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
525 }
526
527 static inline void
528 device_remove_files(struct device *dev)
529 {
530         sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
531 }
532
533 /* this is a simple abstraction for device_register that sets the
534  * correct bus type and adds the bus specific files */
535 static int ccw_device_register(struct ccw_device *cdev)
536 {
537         struct device *dev = &cdev->dev;
538         int ret;
539
540         dev->bus = &ccw_bus_type;
541
542         if ((ret = device_add(dev)))
543                 return ret;
544
545         set_bit(1, &cdev->private->registered);
546         if ((ret = device_add_files(dev))) {
547                 if (test_and_clear_bit(1, &cdev->private->registered))
548                         device_del(dev);
549         }
550         return ret;
551 }
552
553 struct match_data {
554         struct ccw_dev_id dev_id;
555         struct ccw_device * sibling;
556 };
557
558 static int
559 match_devno(struct device * dev, void * data)
560 {
561         struct match_data * d = data;
562         struct ccw_device * cdev;
563
564         cdev = to_ccwdev(dev);
565         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
566             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
567             (cdev != d->sibling)) {
568                 cdev->private->state = DEV_STATE_NOT_OPER;
569                 return 1;
570         }
571         return 0;
572 }
573
574 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
575                                                      struct ccw_device *sibling)
576 {
577         struct device *dev;
578         struct match_data data;
579
580         data.dev_id = *dev_id;
581         data.sibling = sibling;
582         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
583
584         return dev ? to_ccwdev(dev) : NULL;
585 }
586
587 static void
588 ccw_device_add_changed(void *data)
589 {
590
591         struct ccw_device *cdev;
592
593         cdev = data;
594         if (device_add(&cdev->dev)) {
595                 put_device(&cdev->dev);
596                 return;
597         }
598         set_bit(1, &cdev->private->registered);
599         if (device_add_files(&cdev->dev)) {
600                 if (test_and_clear_bit(1, &cdev->private->registered))
601                         device_unregister(&cdev->dev);
602         }
603 }
604
605 extern int css_get_ssd_info(struct subchannel *sch);
606
607 void
608 ccw_device_do_unreg_rereg(void *data)
609 {
610         struct ccw_device *cdev;
611         struct subchannel *sch;
612         int need_rename;
613
614         cdev = data;
615         sch = to_subchannel(cdev->dev.parent);
616         if (cdev->private->dev_id.devno != sch->schib.pmcw.dev) {
617                 /*
618                  * The device number has changed. This is usually only when
619                  * a device has been detached under VM and then re-appeared
620                  * on another subchannel because of a different attachment
621                  * order than before. Ideally, we should should just switch
622                  * subchannels, but unfortunately, this is not possible with
623                  * the current implementation.
624                  * Instead, we search for the old subchannel for this device
625                  * number and deregister so there are no collisions with the
626                  * newly registered ccw_device.
627                  * FIXME: Find another solution so the block layer doesn't
628                  *        get possibly sick...
629                  */
630                 struct ccw_device *other_cdev;
631                 struct ccw_dev_id dev_id;
632
633                 need_rename = 1;
634                 dev_id.devno = sch->schib.pmcw.dev;
635                 dev_id.ssid = sch->schid.ssid;
636                 other_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
637                 if (other_cdev) {
638                         struct subchannel *other_sch;
639
640                         other_sch = to_subchannel(other_cdev->dev.parent);
641                         if (get_device(&other_sch->dev)) {
642                                 stsch(other_sch->schid, &other_sch->schib);
643                                 if (other_sch->schib.pmcw.dnv) {
644                                         other_sch->schib.pmcw.intparm = 0;
645                                         cio_modify(other_sch);
646                                 }
647                                 css_sch_device_unregister(other_sch);
648                         }
649                 }
650                 /* Update ssd info here. */
651                 css_get_ssd_info(sch);
652                 cdev->private->dev_id.devno = sch->schib.pmcw.dev;
653         } else
654                 need_rename = 0;
655         device_remove_files(&cdev->dev);
656         if (test_and_clear_bit(1, &cdev->private->registered))
657                 device_del(&cdev->dev);
658         if (need_rename)
659                 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
660                           sch->schid.ssid, sch->schib.pmcw.dev);
661         PREPARE_WORK(&cdev->private->kick_work,
662                      ccw_device_add_changed, cdev);
663         queue_work(ccw_device_work, &cdev->private->kick_work);
664 }
665
666 static void
667 ccw_device_release(struct device *dev)
668 {
669         struct ccw_device *cdev;
670
671         cdev = to_ccwdev(dev);
672         kfree(cdev->private);
673         kfree(cdev);
674 }
675
676 /*
677  * Register recognized device.
678  */
679 static void
680 io_subchannel_register(void *data)
681 {
682         struct ccw_device *cdev;
683         struct subchannel *sch;
684         int ret;
685         unsigned long flags;
686
687         cdev = data;
688         sch = to_subchannel(cdev->dev.parent);
689
690         if (klist_node_attached(&cdev->dev.knode_parent)) {
691                 bus_rescan_devices(&ccw_bus_type);
692                 goto out;
693         }
694         /* make it known to the system */
695         ret = ccw_device_register(cdev);
696         if (ret) {
697                 printk (KERN_WARNING "%s: could not register %s\n",
698                         __func__, cdev->dev.bus_id);
699                 put_device(&cdev->dev);
700                 spin_lock_irqsave(&sch->lock, flags);
701                 sch->dev.driver_data = NULL;
702                 spin_unlock_irqrestore(&sch->lock, flags);
703                 kfree (cdev->private);
704                 kfree (cdev);
705                 put_device(&sch->dev);
706                 if (atomic_dec_and_test(&ccw_device_init_count))
707                         wake_up(&ccw_device_init_wq);
708                 return;
709         }
710
711         ret = subchannel_add_files(cdev->dev.parent);
712         if (ret)
713                 printk(KERN_WARNING "%s: could not add attributes to %s\n",
714                        __func__, sch->dev.bus_id);
715         put_device(&cdev->dev);
716 out:
717         cdev->private->flags.recog_done = 1;
718         put_device(&sch->dev);
719         wake_up(&cdev->private->wait_q);
720         if (atomic_dec_and_test(&ccw_device_init_count))
721                 wake_up(&ccw_device_init_wq);
722 }
723
724 void
725 ccw_device_call_sch_unregister(void *data)
726 {
727         struct ccw_device *cdev = data;
728         struct subchannel *sch;
729
730         sch = to_subchannel(cdev->dev.parent);
731         css_sch_device_unregister(sch);
732         /* Reset intparm to zeroes. */
733         sch->schib.pmcw.intparm = 0;
734         cio_modify(sch);
735         put_device(&cdev->dev);
736         put_device(&sch->dev);
737 }
738
739 /*
740  * subchannel recognition done. Called from the state machine.
741  */
742 void
743 io_subchannel_recog_done(struct ccw_device *cdev)
744 {
745         struct subchannel *sch;
746
747         if (css_init_done == 0) {
748                 cdev->private->flags.recog_done = 1;
749                 return;
750         }
751         switch (cdev->private->state) {
752         case DEV_STATE_NOT_OPER:
753                 cdev->private->flags.recog_done = 1;
754                 /* Remove device found not operational. */
755                 if (!get_device(&cdev->dev))
756                         break;
757                 sch = to_subchannel(cdev->dev.parent);
758                 PREPARE_WORK(&cdev->private->kick_work,
759                              ccw_device_call_sch_unregister, cdev);
760                 queue_work(slow_path_wq, &cdev->private->kick_work);
761                 if (atomic_dec_and_test(&ccw_device_init_count))
762                         wake_up(&ccw_device_init_wq);
763                 break;
764         case DEV_STATE_BOXED:
765                 /* Device did not respond in time. */
766         case DEV_STATE_OFFLINE:
767                 /* 
768                  * We can't register the device in interrupt context so
769                  * we schedule a work item.
770                  */
771                 if (!get_device(&cdev->dev))
772                         break;
773                 PREPARE_WORK(&cdev->private->kick_work,
774                              io_subchannel_register, cdev);
775                 queue_work(slow_path_wq, &cdev->private->kick_work);
776                 break;
777         }
778 }
779
780 static int
781 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
782 {
783         int rc;
784         struct ccw_device_private *priv;
785
786         sch->dev.driver_data = cdev;
787         sch->driver = &io_subchannel_driver;
788         cdev->ccwlock = &sch->lock;
789
790         /* Init private data. */
791         priv = cdev->private;
792         priv->dev_id.devno = sch->schib.pmcw.dev;
793         priv->dev_id.ssid = sch->schid.ssid;
794         priv->schid = sch->schid;
795         priv->state = DEV_STATE_NOT_OPER;
796         INIT_LIST_HEAD(&priv->cmb_list);
797         init_waitqueue_head(&priv->wait_q);
798         init_timer(&priv->timer);
799
800         /* Set an initial name for the device. */
801         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
802                   sch->schid.ssid, sch->schib.pmcw.dev);
803
804         /* Increase counter of devices currently in recognition. */
805         atomic_inc(&ccw_device_init_count);
806
807         /* Start async. device sensing. */
808         spin_lock_irq(&sch->lock);
809         rc = ccw_device_recognition(cdev);
810         spin_unlock_irq(&sch->lock);
811         if (rc) {
812                 if (atomic_dec_and_test(&ccw_device_init_count))
813                         wake_up(&ccw_device_init_wq);
814         }
815         return rc;
816 }
817
818 static int
819 io_subchannel_probe (struct subchannel *sch)
820 {
821         struct ccw_device *cdev;
822         int rc;
823         unsigned long flags;
824
825         if (sch->dev.driver_data) {
826                 /*
827                  * This subchannel already has an associated ccw_device.
828                  * Register it and exit. This happens for all early
829                  * device, e.g. the console.
830                  */
831                 cdev = sch->dev.driver_data;
832                 device_initialize(&cdev->dev);
833                 ccw_device_register(cdev);
834                 subchannel_add_files(&sch->dev);
835                 /*
836                  * Check if the device is already online. If it is
837                  * the reference count needs to be corrected
838                  * (see ccw_device_online and css_init_done for the
839                  * ugly details).
840                  */
841                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
842                     cdev->private->state != DEV_STATE_OFFLINE &&
843                     cdev->private->state != DEV_STATE_BOXED)
844                         get_device(&cdev->dev);
845                 return 0;
846         }
847         cdev = kzalloc (sizeof(*cdev), GFP_KERNEL);
848         if (!cdev)
849                 return -ENOMEM;
850         cdev->private = kzalloc(sizeof(struct ccw_device_private),
851                                 GFP_KERNEL | GFP_DMA);
852         if (!cdev->private) {
853                 kfree(cdev);
854                 return -ENOMEM;
855         }
856         atomic_set(&cdev->private->onoff, 0);
857         cdev->dev.parent = &sch->dev;
858         cdev->dev.release = ccw_device_release;
859         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
860         /* Do first half of device_register. */
861         device_initialize(&cdev->dev);
862
863         if (!get_device(&sch->dev)) {
864                 if (cdev->dev.release)
865                         cdev->dev.release(&cdev->dev);
866                 return -ENODEV;
867         }
868
869         rc = io_subchannel_recog(cdev, sch);
870         if (rc) {
871                 spin_lock_irqsave(&sch->lock, flags);
872                 sch->dev.driver_data = NULL;
873                 spin_unlock_irqrestore(&sch->lock, flags);
874                 if (cdev->dev.release)
875                         cdev->dev.release(&cdev->dev);
876         }
877
878         return rc;
879 }
880
881 static void
882 ccw_device_unregister(void *data)
883 {
884         struct ccw_device *cdev;
885
886         cdev = (struct ccw_device *)data;
887         if (test_and_clear_bit(1, &cdev->private->registered))
888                 device_unregister(&cdev->dev);
889         put_device(&cdev->dev);
890 }
891
892 static int
893 io_subchannel_remove (struct subchannel *sch)
894 {
895         struct ccw_device *cdev;
896         unsigned long flags;
897
898         if (!sch->dev.driver_data)
899                 return 0;
900         cdev = sch->dev.driver_data;
901         /* Set ccw device to not operational and drop reference. */
902         spin_lock_irqsave(cdev->ccwlock, flags);
903         sch->dev.driver_data = NULL;
904         cdev->private->state = DEV_STATE_NOT_OPER;
905         spin_unlock_irqrestore(cdev->ccwlock, flags);
906         /*
907          * Put unregistration on workqueue to avoid livelocks on the css bus
908          * semaphore.
909          */
910         if (get_device(&cdev->dev)) {
911                 PREPARE_WORK(&cdev->private->kick_work,
912                              ccw_device_unregister, cdev);
913                 queue_work(ccw_device_work, &cdev->private->kick_work);
914         }
915         return 0;
916 }
917
918 static int
919 io_subchannel_notify(struct device *dev, int event)
920 {
921         struct ccw_device *cdev;
922
923         cdev = dev->driver_data;
924         if (!cdev)
925                 return 0;
926         if (!cdev->drv)
927                 return 0;
928         if (!cdev->online)
929                 return 0;
930         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
931 }
932
933 static void
934 io_subchannel_verify(struct device *dev)
935 {
936         struct ccw_device *cdev;
937
938         cdev = dev->driver_data;
939         if (cdev)
940                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
941 }
942
943 static void
944 io_subchannel_ioterm(struct device *dev)
945 {
946         struct ccw_device *cdev;
947
948         cdev = dev->driver_data;
949         if (!cdev)
950                 return;
951         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
952         if (cdev->handler)
953                 cdev->handler(cdev, cdev->private->intparm,
954                               ERR_PTR(-EIO));
955 }
956
957 static void
958 io_subchannel_shutdown(struct subchannel *sch)
959 {
960         struct ccw_device *cdev;
961         int ret;
962
963         cdev = sch->dev.driver_data;
964
965         if (cio_is_console(sch->schid))
966                 return;
967         if (!sch->schib.pmcw.ena)
968                 /* Nothing to do. */
969                 return;
970         ret = cio_disable_subchannel(sch);
971         if (ret != -EBUSY)
972                 /* Subchannel is disabled, we're done. */
973                 return;
974         cdev->private->state = DEV_STATE_QUIESCE;
975         if (cdev->handler)
976                 cdev->handler(cdev, cdev->private->intparm,
977                               ERR_PTR(-EIO));
978         ret = ccw_device_cancel_halt_clear(cdev);
979         if (ret == -EBUSY) {
980                 ccw_device_set_timeout(cdev, HZ/10);
981                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
982         }
983         cio_disable_subchannel(sch);
984 }
985
986 #ifdef CONFIG_CCW_CONSOLE
987 static struct ccw_device console_cdev;
988 static struct ccw_device_private console_private;
989 static int console_cdev_in_use;
990
991 static int
992 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
993 {
994         int rc;
995
996         /* Initialize the ccw_device structure. */
997         cdev->dev.parent= &sch->dev;
998         rc = io_subchannel_recog(cdev, sch);
999         if (rc)
1000                 return rc;
1001
1002         /* Now wait for the async. recognition to come to an end. */
1003         spin_lock_irq(cdev->ccwlock);
1004         while (!dev_fsm_final_state(cdev))
1005                 wait_cons_dev();
1006         rc = -EIO;
1007         if (cdev->private->state != DEV_STATE_OFFLINE)
1008                 goto out_unlock;
1009         ccw_device_online(cdev);
1010         while (!dev_fsm_final_state(cdev))
1011                 wait_cons_dev();
1012         if (cdev->private->state != DEV_STATE_ONLINE)
1013                 goto out_unlock;
1014         rc = 0;
1015 out_unlock:
1016         spin_unlock_irq(cdev->ccwlock);
1017         return 0;
1018 }
1019
1020 struct ccw_device *
1021 ccw_device_probe_console(void)
1022 {
1023         struct subchannel *sch;
1024         int ret;
1025
1026         if (xchg(&console_cdev_in_use, 1) != 0)
1027                 return ERR_PTR(-EBUSY);
1028         sch = cio_probe_console();
1029         if (IS_ERR(sch)) {
1030                 console_cdev_in_use = 0;
1031                 return (void *) sch;
1032         }
1033         memset(&console_cdev, 0, sizeof(struct ccw_device));
1034         memset(&console_private, 0, sizeof(struct ccw_device_private));
1035         console_cdev.private = &console_private;
1036         ret = ccw_device_console_enable(&console_cdev, sch);
1037         if (ret) {
1038                 cio_release_console();
1039                 console_cdev_in_use = 0;
1040                 return ERR_PTR(ret);
1041         }
1042         console_cdev.online = 1;
1043         return &console_cdev;
1044 }
1045 #endif
1046
1047 /*
1048  * get ccw_device matching the busid, but only if owned by cdrv
1049  */
1050 static int
1051 __ccwdev_check_busid(struct device *dev, void *id)
1052 {
1053         char *bus_id;
1054
1055         bus_id = id;
1056
1057         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1058 }
1059
1060
1061 struct ccw_device *
1062 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1063 {
1064         struct device *dev;
1065         struct device_driver *drv;
1066
1067         drv = get_driver(&cdrv->driver);
1068         if (!drv)
1069                 return NULL;
1070
1071         dev = driver_find_device(drv, NULL, (void *)bus_id,
1072                                  __ccwdev_check_busid);
1073         put_driver(drv);
1074
1075         return dev ? to_ccwdev(dev) : NULL;
1076 }
1077
1078 /************************** device driver handling ************************/
1079
1080 /* This is the implementation of the ccw_driver class. The probe, remove
1081  * and release methods are initially very similar to the device_driver
1082  * implementations, with the difference that they have ccw_device
1083  * arguments.
1084  *
1085  * A ccw driver also contains the information that is needed for
1086  * device matching.
1087  */
1088 static int
1089 ccw_device_probe (struct device *dev)
1090 {
1091         struct ccw_device *cdev = to_ccwdev(dev);
1092         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1093         int ret;
1094
1095         cdev->drv = cdrv; /* to let the driver call _set_online */
1096
1097         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1098
1099         if (ret) {
1100                 cdev->drv = NULL;
1101                 return ret;
1102         }
1103
1104         return 0;
1105 }
1106
1107 static int
1108 ccw_device_remove (struct device *dev)
1109 {
1110         struct ccw_device *cdev = to_ccwdev(dev);
1111         struct ccw_driver *cdrv = cdev->drv;
1112         int ret;
1113
1114         pr_debug("removing device %s\n", cdev->dev.bus_id);
1115         if (cdrv->remove)
1116                 cdrv->remove(cdev);
1117         if (cdev->online) {
1118                 cdev->online = 0;
1119                 spin_lock_irq(cdev->ccwlock);
1120                 ret = ccw_device_offline(cdev);
1121                 spin_unlock_irq(cdev->ccwlock);
1122                 if (ret == 0)
1123                         wait_event(cdev->private->wait_q,
1124                                    dev_fsm_final_state(cdev));
1125                 else
1126                         //FIXME: we can't fail!
1127                         pr_debug("ccw_device_offline returned %d, device %s\n",
1128                                  ret, cdev->dev.bus_id);
1129         }
1130         ccw_device_set_timeout(cdev, 0);
1131         cdev->drv = NULL;
1132         return 0;
1133 }
1134
1135 struct bus_type ccw_bus_type = {
1136         .name   = "ccw",
1137         .match  = ccw_bus_match,
1138         .uevent = ccw_uevent,
1139         .probe  = ccw_device_probe,
1140         .remove = ccw_device_remove,
1141 };
1142
1143 int
1144 ccw_driver_register (struct ccw_driver *cdriver)
1145 {
1146         struct device_driver *drv = &cdriver->driver;
1147
1148         drv->bus = &ccw_bus_type;
1149         drv->name = cdriver->name;
1150
1151         return driver_register(drv);
1152 }
1153
1154 void
1155 ccw_driver_unregister (struct ccw_driver *cdriver)
1156 {
1157         driver_unregister(&cdriver->driver);
1158 }
1159
1160 /* Helper func for qdio. */
1161 struct subchannel_id
1162 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1163 {
1164         struct subchannel *sch;
1165
1166         sch = to_subchannel(cdev->dev.parent);
1167         return sch->schid;
1168 }
1169
1170 MODULE_LICENSE("GPL");
1171 EXPORT_SYMBOL(ccw_device_set_online);
1172 EXPORT_SYMBOL(ccw_device_set_offline);
1173 EXPORT_SYMBOL(ccw_driver_register);
1174 EXPORT_SYMBOL(ccw_driver_unregister);
1175 EXPORT_SYMBOL(get_ccwdev_by_busid);
1176 EXPORT_SYMBOL(ccw_bus_type);
1177 EXPORT_SYMBOL(ccw_device_work);
1178 EXPORT_SYMBOL(ccw_device_notify_work);
1179 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);