Merge branches 'armv7', 'at91', 'misc' and 'omap' into devel
[linux-2.6] / drivers / s390 / cio / device.c
1 /*
2  *  drivers/s390/cio/device.c
3  *  bus driver for ccw devices
4  *
5  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
6  *                       IBM Corporation
7  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
8  *               Cornelia Huck (cornelia.huck@de.ibm.com)
9  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
10  */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/spinlock.h>
14 #include <linux/errno.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/list.h>
18 #include <linux/device.h>
19 #include <linux/workqueue.h>
20
21 #include <asm/ccwdev.h>
22 #include <asm/cio.h>
23 #include <asm/param.h>          /* HZ */
24
25 #include "cio.h"
26 #include "cio_debug.h"
27 #include "css.h"
28 #include "device.h"
29 #include "ioasm.h"
30
31 /******************* bus type handling ***********************/
32
33 /* The Linux driver model distinguishes between a bus type and
34  * the bus itself. Of course we only have one channel
35  * subsystem driver and one channel system per machine, but
36  * we still use the abstraction. T.R. says it's a good idea. */
37 static int
38 ccw_bus_match (struct device * dev, struct device_driver * drv)
39 {
40         struct ccw_device *cdev = to_ccwdev(dev);
41         struct ccw_driver *cdrv = to_ccwdrv(drv);
42         const struct ccw_device_id *ids = cdrv->ids, *found;
43
44         if (!ids)
45                 return 0;
46
47         found = ccw_device_id_match(ids, &cdev->id);
48         if (!found)
49                 return 0;
50
51         cdev->id.driver_info = found->driver_info;
52
53         return 1;
54 }
55
56 /* Store modalias string delimited by prefix/suffix string into buffer with
57  * specified size. Return length of resulting string (excluding trailing '\0')
58  * even if string doesn't fit buffer (snprintf semantics). */
59 static int snprint_alias(char *buf, size_t size,
60                          struct ccw_device_id *id, const char *suffix)
61 {
62         int len;
63
64         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
65         if (len > size)
66                 return len;
67         buf += len;
68         size -= len;
69
70         if (id->dev_type != 0)
71                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
72                                 id->dev_model, suffix);
73         else
74                 len += snprintf(buf, size, "dtdm%s", suffix);
75
76         return len;
77 }
78
79 /* Set up environment variables for ccw device uevent. Return 0 on success,
80  * non-zero otherwise. */
81 static int ccw_uevent(struct device *dev, char **envp, int num_envp,
82                       char *buffer, int buffer_size)
83 {
84         struct ccw_device *cdev = to_ccwdev(dev);
85         struct ccw_device_id *id = &(cdev->id);
86         int i = 0;
87         int len = 0;
88         int ret;
89         char modalias_buf[30];
90
91         /* CU_TYPE= */
92         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
93                              "CU_TYPE=%04X", id->cu_type);
94         if (ret)
95                 return ret;
96
97         /* CU_MODEL= */
98         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
99                              "CU_MODEL=%02X", id->cu_model);
100         if (ret)
101                 return ret;
102
103         /* The next two can be zero, that's ok for us */
104         /* DEV_TYPE= */
105         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
106                              "DEV_TYPE=%04X", id->dev_type);
107         if (ret)
108                 return ret;
109
110         /* DEV_MODEL= */
111         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
112                              "DEV_MODEL=%02X", id->dev_model);
113         if (ret)
114                 return ret;
115
116         /* MODALIAS=  */
117         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
118         ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
119                              "MODALIAS=%s", modalias_buf);
120         return ret;
121 }
122
123 struct bus_type ccw_bus_type;
124
125 static int io_subchannel_probe (struct subchannel *);
126 static int io_subchannel_remove (struct subchannel *);
127 static int io_subchannel_notify(struct device *, int);
128 static void io_subchannel_verify(struct device *);
129 static void io_subchannel_ioterm(struct device *);
130 static void io_subchannel_shutdown(struct subchannel *);
131
132 struct css_driver io_subchannel_driver = {
133         .subchannel_type = SUBCHANNEL_TYPE_IO,
134         .drv = {
135                 .name = "io_subchannel",
136                 .bus  = &css_bus_type,
137         },
138         .irq = io_subchannel_irq,
139         .notify = io_subchannel_notify,
140         .verify = io_subchannel_verify,
141         .termination = io_subchannel_ioterm,
142         .probe = io_subchannel_probe,
143         .remove = io_subchannel_remove,
144         .shutdown = io_subchannel_shutdown,
145 };
146
147 struct workqueue_struct *ccw_device_work;
148 struct workqueue_struct *ccw_device_notify_work;
149 wait_queue_head_t ccw_device_init_wq;
150 atomic_t ccw_device_init_count;
151
152 static int __init
153 init_ccw_bus_type (void)
154 {
155         int ret;
156
157         init_waitqueue_head(&ccw_device_init_wq);
158         atomic_set(&ccw_device_init_count, 0);
159
160         ccw_device_work = create_singlethread_workqueue("cio");
161         if (!ccw_device_work)
162                 return -ENOMEM; /* FIXME: better errno ? */
163         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
164         if (!ccw_device_notify_work) {
165                 ret = -ENOMEM; /* FIXME: better errno ? */
166                 goto out_err;
167         }
168         slow_path_wq = create_singlethread_workqueue("kslowcrw");
169         if (!slow_path_wq) {
170                 ret = -ENOMEM; /* FIXME: better errno ? */
171                 goto out_err;
172         }
173         if ((ret = bus_register (&ccw_bus_type)))
174                 goto out_err;
175
176         if ((ret = driver_register(&io_subchannel_driver.drv)))
177                 goto out_err;
178
179         wait_event(ccw_device_init_wq,
180                    atomic_read(&ccw_device_init_count) == 0);
181         flush_workqueue(ccw_device_work);
182         return 0;
183 out_err:
184         if (ccw_device_work)
185                 destroy_workqueue(ccw_device_work);
186         if (ccw_device_notify_work)
187                 destroy_workqueue(ccw_device_notify_work);
188         if (slow_path_wq)
189                 destroy_workqueue(slow_path_wq);
190         return ret;
191 }
192
193 static void __exit
194 cleanup_ccw_bus_type (void)
195 {
196         driver_unregister(&io_subchannel_driver.drv);
197         bus_unregister(&ccw_bus_type);
198         destroy_workqueue(ccw_device_notify_work);
199         destroy_workqueue(ccw_device_work);
200 }
201
202 subsys_initcall(init_ccw_bus_type);
203 module_exit(cleanup_ccw_bus_type);
204
205 /************************ device handling **************************/
206
207 /*
208  * A ccw_device has some interfaces in sysfs in addition to the
209  * standard ones.
210  * The following entries are designed to export the information which
211  * resided in 2.4 in /proc/subchannels. Subchannel and device number
212  * are obvious, so they don't have an entry :)
213  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
214  */
215 static ssize_t
216 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
217 {
218         struct subchannel *sch = to_subchannel(dev);
219         struct chsc_ssd_info *ssd = &sch->ssd_info;
220         ssize_t ret = 0;
221         int chp;
222         int mask;
223
224         for (chp = 0; chp < 8; chp++) {
225                 mask = 0x80 >> chp;
226                 if (ssd->path_mask & mask)
227                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
228                 else
229                         ret += sprintf(buf + ret, "00 ");
230         }
231         ret += sprintf (buf+ret, "\n");
232         return min((ssize_t)PAGE_SIZE, ret);
233 }
234
235 static ssize_t
236 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
237 {
238         struct subchannel *sch = to_subchannel(dev);
239         struct pmcw *pmcw = &sch->schib.pmcw;
240
241         return sprintf (buf, "%02x %02x %02x\n",
242                         pmcw->pim, pmcw->pam, pmcw->pom);
243 }
244
245 static ssize_t
246 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
247 {
248         struct ccw_device *cdev = to_ccwdev(dev);
249         struct ccw_device_id *id = &(cdev->id);
250
251         if (id->dev_type != 0)
252                 return sprintf(buf, "%04x/%02x\n",
253                                 id->dev_type, id->dev_model);
254         else
255                 return sprintf(buf, "n/a\n");
256 }
257
258 static ssize_t
259 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
260 {
261         struct ccw_device *cdev = to_ccwdev(dev);
262         struct ccw_device_id *id = &(cdev->id);
263
264         return sprintf(buf, "%04x/%02x\n",
265                        id->cu_type, id->cu_model);
266 }
267
268 static ssize_t
269 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
270 {
271         struct ccw_device *cdev = to_ccwdev(dev);
272         struct ccw_device_id *id = &(cdev->id);
273         int len;
274
275         len = snprint_alias(buf, PAGE_SIZE, id, "\n") + 1;
276
277         return len > PAGE_SIZE ? PAGE_SIZE : len;
278 }
279
280 static ssize_t
281 online_show (struct device *dev, struct device_attribute *attr, char *buf)
282 {
283         struct ccw_device *cdev = to_ccwdev(dev);
284
285         return sprintf(buf, cdev->online ? "1\n" : "0\n");
286 }
287
288 int ccw_device_is_orphan(struct ccw_device *cdev)
289 {
290         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
291 }
292
293 static void ccw_device_unregister(struct ccw_device *cdev)
294 {
295         if (test_and_clear_bit(1, &cdev->private->registered))
296                 device_del(&cdev->dev);
297 }
298
299 static void
300 ccw_device_remove_disconnected(struct ccw_device *cdev)
301 {
302         struct subchannel *sch;
303         unsigned long flags;
304         /*
305          * Forced offline in disconnected state means
306          * 'throw away device'.
307          */
308         if (ccw_device_is_orphan(cdev)) {
309                 /* Deregister ccw device. */
310                 spin_lock_irqsave(cdev->ccwlock, flags);
311                 cdev->private->state = DEV_STATE_NOT_OPER;
312                 spin_unlock_irqrestore(cdev->ccwlock, flags);
313                 ccw_device_unregister(cdev);
314                 put_device(&cdev->dev);
315                 return ;
316         }
317         sch = to_subchannel(cdev->dev.parent);
318         css_sch_device_unregister(sch);
319         /* Reset intparm to zeroes. */
320         sch->schib.pmcw.intparm = 0;
321         cio_modify(sch);
322         put_device(&sch->dev);
323 }
324
325 int
326 ccw_device_set_offline(struct ccw_device *cdev)
327 {
328         int ret;
329
330         if (!cdev)
331                 return -ENODEV;
332         if (!cdev->online || !cdev->drv)
333                 return -EINVAL;
334
335         if (cdev->drv->set_offline) {
336                 ret = cdev->drv->set_offline(cdev);
337                 if (ret != 0)
338                         return ret;
339         }
340         cdev->online = 0;
341         spin_lock_irq(cdev->ccwlock);
342         ret = ccw_device_offline(cdev);
343         if (ret == -ENODEV) {
344                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
345                         cdev->private->state = DEV_STATE_OFFLINE;
346                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
347                 }
348                 spin_unlock_irq(cdev->ccwlock);
349                 return ret;
350         }
351         spin_unlock_irq(cdev->ccwlock);
352         if (ret == 0)
353                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
354         else {
355                 pr_debug("ccw_device_offline returned %d, device %s\n",
356                          ret, cdev->dev.bus_id);
357                 cdev->online = 1;
358         }
359         return ret;
360 }
361
362 int
363 ccw_device_set_online(struct ccw_device *cdev)
364 {
365         int ret;
366
367         if (!cdev)
368                 return -ENODEV;
369         if (cdev->online || !cdev->drv)
370                 return -EINVAL;
371
372         spin_lock_irq(cdev->ccwlock);
373         ret = ccw_device_online(cdev);
374         spin_unlock_irq(cdev->ccwlock);
375         if (ret == 0)
376                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
377         else {
378                 pr_debug("ccw_device_online returned %d, device %s\n",
379                          ret, cdev->dev.bus_id);
380                 return ret;
381         }
382         if (cdev->private->state != DEV_STATE_ONLINE)
383                 return -ENODEV;
384         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
385                 cdev->online = 1;
386                 return 0;
387         }
388         spin_lock_irq(cdev->ccwlock);
389         ret = ccw_device_offline(cdev);
390         spin_unlock_irq(cdev->ccwlock);
391         if (ret == 0)
392                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
393         else 
394                 pr_debug("ccw_device_offline returned %d, device %s\n",
395                          ret, cdev->dev.bus_id);
396         return (ret == 0) ? -ENODEV : ret;
397 }
398
399 static void online_store_handle_offline(struct ccw_device *cdev)
400 {
401         if (cdev->private->state == DEV_STATE_DISCONNECTED)
402                 ccw_device_remove_disconnected(cdev);
403         else if (cdev->drv && cdev->drv->set_offline)
404                 ccw_device_set_offline(cdev);
405 }
406
407 static int online_store_recog_and_online(struct ccw_device *cdev)
408 {
409         int ret;
410
411         /* Do device recognition, if needed. */
412         if (cdev->id.cu_type == 0) {
413                 ret = ccw_device_recognition(cdev);
414                 if (ret) {
415                         printk(KERN_WARNING"Couldn't start recognition "
416                                "for device %s (ret=%d)\n",
417                                cdev->dev.bus_id, ret);
418                         return ret;
419                 }
420                 wait_event(cdev->private->wait_q,
421                            cdev->private->flags.recog_done);
422         }
423         if (cdev->drv && cdev->drv->set_online)
424                 ccw_device_set_online(cdev);
425         return 0;
426 }
427 static void online_store_handle_online(struct ccw_device *cdev, int force)
428 {
429         int ret;
430
431         ret = online_store_recog_and_online(cdev);
432         if (ret)
433                 return;
434         if (force && cdev->private->state == DEV_STATE_BOXED) {
435                 ret = ccw_device_stlck(cdev);
436                 if (ret) {
437                         printk(KERN_WARNING"ccw_device_stlck for device %s "
438                                "returned %d!\n", cdev->dev.bus_id, ret);
439                         return;
440                 }
441                 if (cdev->id.cu_type == 0)
442                         cdev->private->state = DEV_STATE_NOT_OPER;
443                 online_store_recog_and_online(cdev);
444         }
445
446 }
447
448 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
449                              const char *buf, size_t count)
450 {
451         struct ccw_device *cdev = to_ccwdev(dev);
452         int i, force;
453         char *tmp;
454
455         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
456                 return -EAGAIN;
457
458         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
459                 atomic_set(&cdev->private->onoff, 0);
460                 return -EINVAL;
461         }
462         if (!strncmp(buf, "force\n", count)) {
463                 force = 1;
464                 i = 1;
465         } else {
466                 force = 0;
467                 i = simple_strtoul(buf, &tmp, 16);
468         }
469
470         switch (i) {
471         case 0:
472                 online_store_handle_offline(cdev);
473                 break;
474         case 1:
475                 online_store_handle_online(cdev, force);
476                 break;
477         default:
478                 count = -EINVAL;
479         }
480         if (cdev->drv)
481                 module_put(cdev->drv->owner);
482         atomic_set(&cdev->private->onoff, 0);
483         return count;
484 }
485
486 static ssize_t
487 available_show (struct device *dev, struct device_attribute *attr, char *buf)
488 {
489         struct ccw_device *cdev = to_ccwdev(dev);
490         struct subchannel *sch;
491
492         if (ccw_device_is_orphan(cdev))
493                 return sprintf(buf, "no device\n");
494         switch (cdev->private->state) {
495         case DEV_STATE_BOXED:
496                 return sprintf(buf, "boxed\n");
497         case DEV_STATE_DISCONNECTED:
498         case DEV_STATE_DISCONNECTED_SENSE_ID:
499         case DEV_STATE_NOT_OPER:
500                 sch = to_subchannel(dev->parent);
501                 if (!sch->lpm)
502                         return sprintf(buf, "no path\n");
503                 else
504                         return sprintf(buf, "no device\n");
505         default:
506                 /* All other states considered fine. */
507                 return sprintf(buf, "good\n");
508         }
509 }
510
511 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
512 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
513 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
514 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
515 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
516 static DEVICE_ATTR(online, 0644, online_show, online_store);
517 extern struct device_attribute dev_attr_cmb_enable;
518 static DEVICE_ATTR(availability, 0444, available_show, NULL);
519
520 static struct attribute * subch_attrs[] = {
521         &dev_attr_chpids.attr,
522         &dev_attr_pimpampom.attr,
523         NULL,
524 };
525
526 static struct attribute_group subch_attr_group = {
527         .attrs = subch_attrs,
528 };
529
530 struct attribute_group *subch_attr_groups[] = {
531         &subch_attr_group,
532         NULL,
533 };
534
535 static struct attribute * ccwdev_attrs[] = {
536         &dev_attr_devtype.attr,
537         &dev_attr_cutype.attr,
538         &dev_attr_modalias.attr,
539         &dev_attr_online.attr,
540         &dev_attr_cmb_enable.attr,
541         &dev_attr_availability.attr,
542         NULL,
543 };
544
545 static struct attribute_group ccwdev_attr_group = {
546         .attrs = ccwdev_attrs,
547 };
548
549 struct attribute_group *ccwdev_attr_groups[] = {
550         &ccwdev_attr_group,
551         NULL,
552 };
553
554 /* this is a simple abstraction for device_register that sets the
555  * correct bus type and adds the bus specific files */
556 static int ccw_device_register(struct ccw_device *cdev)
557 {
558         struct device *dev = &cdev->dev;
559         int ret;
560
561         dev->bus = &ccw_bus_type;
562
563         if ((ret = device_add(dev)))
564                 return ret;
565
566         set_bit(1, &cdev->private->registered);
567         return ret;
568 }
569
570 struct match_data {
571         struct ccw_dev_id dev_id;
572         struct ccw_device * sibling;
573 };
574
575 static int
576 match_devno(struct device * dev, void * data)
577 {
578         struct match_data * d = data;
579         struct ccw_device * cdev;
580
581         cdev = to_ccwdev(dev);
582         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
583             !ccw_device_is_orphan(cdev) &&
584             ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
585             (cdev != d->sibling))
586                 return 1;
587         return 0;
588 }
589
590 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
591                                                      struct ccw_device *sibling)
592 {
593         struct device *dev;
594         struct match_data data;
595
596         data.dev_id = *dev_id;
597         data.sibling = sibling;
598         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
599
600         return dev ? to_ccwdev(dev) : NULL;
601 }
602
603 static int match_orphan(struct device *dev, void *data)
604 {
605         struct ccw_dev_id *dev_id;
606         struct ccw_device *cdev;
607
608         dev_id = data;
609         cdev = to_ccwdev(dev);
610         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
611 }
612
613 static struct ccw_device *
614 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
615                               struct ccw_dev_id *dev_id)
616 {
617         struct device *dev;
618
619         dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
620                                 match_orphan);
621
622         return dev ? to_ccwdev(dev) : NULL;
623 }
624
625 static void
626 ccw_device_add_changed(struct work_struct *work)
627 {
628         struct ccw_device_private *priv;
629         struct ccw_device *cdev;
630
631         priv = container_of(work, struct ccw_device_private, kick_work);
632         cdev = priv->cdev;
633         if (device_add(&cdev->dev)) {
634                 put_device(&cdev->dev);
635                 return;
636         }
637         set_bit(1, &cdev->private->registered);
638 }
639
640 void ccw_device_do_unreg_rereg(struct work_struct *work)
641 {
642         struct ccw_device_private *priv;
643         struct ccw_device *cdev;
644         struct subchannel *sch;
645
646         priv = container_of(work, struct ccw_device_private, kick_work);
647         cdev = priv->cdev;
648         sch = to_subchannel(cdev->dev.parent);
649
650         ccw_device_unregister(cdev);
651         PREPARE_WORK(&cdev->private->kick_work,
652                      ccw_device_add_changed);
653         queue_work(ccw_device_work, &cdev->private->kick_work);
654 }
655
656 static void
657 ccw_device_release(struct device *dev)
658 {
659         struct ccw_device *cdev;
660
661         cdev = to_ccwdev(dev);
662         kfree(cdev->private);
663         kfree(cdev);
664 }
665
666 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
667 {
668         struct ccw_device *cdev;
669
670         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
671         if (cdev) {
672                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
673                                         GFP_KERNEL | GFP_DMA);
674                 if (cdev->private)
675                         return cdev;
676         }
677         kfree(cdev);
678         return ERR_PTR(-ENOMEM);
679 }
680
681 static int io_subchannel_initialize_dev(struct subchannel *sch,
682                                         struct ccw_device *cdev)
683 {
684         cdev->private->cdev = cdev;
685         atomic_set(&cdev->private->onoff, 0);
686         cdev->dev.parent = &sch->dev;
687         cdev->dev.release = ccw_device_release;
688         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
689         cdev->dev.groups = ccwdev_attr_groups;
690         /* Do first half of device_register. */
691         device_initialize(&cdev->dev);
692         if (!get_device(&sch->dev)) {
693                 if (cdev->dev.release)
694                         cdev->dev.release(&cdev->dev);
695                 return -ENODEV;
696         }
697         return 0;
698 }
699
700 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
701 {
702         struct ccw_device *cdev;
703         int ret;
704
705         cdev = io_subchannel_allocate_dev(sch);
706         if (!IS_ERR(cdev)) {
707                 ret = io_subchannel_initialize_dev(sch, cdev);
708                 if (ret) {
709                         kfree(cdev);
710                         cdev = ERR_PTR(ret);
711                 }
712         }
713         return cdev;
714 }
715
716 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
717
718 static void sch_attach_device(struct subchannel *sch,
719                               struct ccw_device *cdev)
720 {
721         css_update_ssd_info(sch);
722         spin_lock_irq(sch->lock);
723         sch->dev.driver_data = cdev;
724         cdev->private->schid = sch->schid;
725         cdev->ccwlock = sch->lock;
726         device_trigger_reprobe(sch);
727         spin_unlock_irq(sch->lock);
728 }
729
730 static void sch_attach_disconnected_device(struct subchannel *sch,
731                                            struct ccw_device *cdev)
732 {
733         struct subchannel *other_sch;
734         int ret;
735
736         other_sch = to_subchannel(get_device(cdev->dev.parent));
737         ret = device_move(&cdev->dev, &sch->dev);
738         if (ret) {
739                 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
740                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
741                               cdev->private->dev_id.devno, ret);
742                 put_device(&other_sch->dev);
743                 return;
744         }
745         other_sch->dev.driver_data = NULL;
746         /* No need to keep a subchannel without ccw device around. */
747         css_sch_device_unregister(other_sch);
748         put_device(&other_sch->dev);
749         sch_attach_device(sch, cdev);
750 }
751
752 static void sch_attach_orphaned_device(struct subchannel *sch,
753                                        struct ccw_device *cdev)
754 {
755         int ret;
756
757         /* Try to move the ccw device to its new subchannel. */
758         ret = device_move(&cdev->dev, &sch->dev);
759         if (ret) {
760                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
761                               "failed (ret=%d)!\n",
762                               cdev->private->dev_id.ssid,
763                               cdev->private->dev_id.devno, ret);
764                 return;
765         }
766         sch_attach_device(sch, cdev);
767 }
768
769 static void sch_create_and_recog_new_device(struct subchannel *sch)
770 {
771         struct ccw_device *cdev;
772
773         /* Need to allocate a new ccw device. */
774         cdev = io_subchannel_create_ccwdev(sch);
775         if (IS_ERR(cdev)) {
776                 /* OK, we did everything we could... */
777                 css_sch_device_unregister(sch);
778                 return;
779         }
780         spin_lock_irq(sch->lock);
781         sch->dev.driver_data = cdev;
782         spin_unlock_irq(sch->lock);
783         /* Start recognition for the new ccw device. */
784         if (io_subchannel_recog(cdev, sch)) {
785                 spin_lock_irq(sch->lock);
786                 sch->dev.driver_data = NULL;
787                 spin_unlock_irq(sch->lock);
788                 if (cdev->dev.release)
789                         cdev->dev.release(&cdev->dev);
790                 css_sch_device_unregister(sch);
791         }
792 }
793
794
795 void ccw_device_move_to_orphanage(struct work_struct *work)
796 {
797         struct ccw_device_private *priv;
798         struct ccw_device *cdev;
799         struct ccw_device *replacing_cdev;
800         struct subchannel *sch;
801         int ret;
802         struct channel_subsystem *css;
803         struct ccw_dev_id dev_id;
804
805         priv = container_of(work, struct ccw_device_private, kick_work);
806         cdev = priv->cdev;
807         sch = to_subchannel(cdev->dev.parent);
808         css = to_css(sch->dev.parent);
809         dev_id.devno = sch->schib.pmcw.dev;
810         dev_id.ssid = sch->schid.ssid;
811
812         /*
813          * Move the orphaned ccw device to the orphanage so the replacing
814          * ccw device can take its place on the subchannel.
815          */
816         ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
817         if (ret) {
818                 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
819                               "(ret=%d)!\n", cdev->private->dev_id.ssid,
820                               cdev->private->dev_id.devno, ret);
821                 return;
822         }
823         cdev->ccwlock = css->pseudo_subchannel->lock;
824         /*
825          * Search for the replacing ccw device
826          * - among the disconnected devices
827          * - in the orphanage
828          */
829         replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
830         if (replacing_cdev) {
831                 sch_attach_disconnected_device(sch, replacing_cdev);
832                 return;
833         }
834         replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
835         if (replacing_cdev) {
836                 sch_attach_orphaned_device(sch, replacing_cdev);
837                 return;
838         }
839         sch_create_and_recog_new_device(sch);
840 }
841
842 /*
843  * Register recognized device.
844  */
845 static void
846 io_subchannel_register(struct work_struct *work)
847 {
848         struct ccw_device_private *priv;
849         struct ccw_device *cdev;
850         struct subchannel *sch;
851         int ret;
852         unsigned long flags;
853
854         priv = container_of(work, struct ccw_device_private, kick_work);
855         cdev = priv->cdev;
856         sch = to_subchannel(cdev->dev.parent);
857         css_update_ssd_info(sch);
858         /*
859          * io_subchannel_register() will also be called after device
860          * recognition has been done for a boxed device (which will already
861          * be registered). We need to reprobe since we may now have sense id
862          * information.
863          */
864         if (klist_node_attached(&cdev->dev.knode_parent)) {
865                 if (!cdev->drv) {
866                         ret = device_reprobe(&cdev->dev);
867                         if (ret)
868                                 /* We can't do much here. */
869                                 dev_info(&cdev->dev, "device_reprobe() returned"
870                                          " %d\n", ret);
871                 }
872                 goto out;
873         }
874         /*
875          * Now we know this subchannel will stay, we can throw
876          * our delayed uevent.
877          */
878         sch->dev.uevent_suppress = 0;
879         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
880         /* make it known to the system */
881         ret = ccw_device_register(cdev);
882         if (ret) {
883                 printk (KERN_WARNING "%s: could not register %s\n",
884                         __func__, cdev->dev.bus_id);
885                 put_device(&cdev->dev);
886                 spin_lock_irqsave(sch->lock, flags);
887                 sch->dev.driver_data = NULL;
888                 spin_unlock_irqrestore(sch->lock, flags);
889                 kfree (cdev->private);
890                 kfree (cdev);
891                 put_device(&sch->dev);
892                 if (atomic_dec_and_test(&ccw_device_init_count))
893                         wake_up(&ccw_device_init_wq);
894                 return;
895         }
896         put_device(&cdev->dev);
897 out:
898         cdev->private->flags.recog_done = 1;
899         put_device(&sch->dev);
900         wake_up(&cdev->private->wait_q);
901         if (atomic_dec_and_test(&ccw_device_init_count))
902                 wake_up(&ccw_device_init_wq);
903 }
904
905 void
906 ccw_device_call_sch_unregister(struct work_struct *work)
907 {
908         struct ccw_device_private *priv;
909         struct ccw_device *cdev;
910         struct subchannel *sch;
911
912         priv = container_of(work, struct ccw_device_private, kick_work);
913         cdev = priv->cdev;
914         sch = to_subchannel(cdev->dev.parent);
915         css_sch_device_unregister(sch);
916         /* Reset intparm to zeroes. */
917         sch->schib.pmcw.intparm = 0;
918         cio_modify(sch);
919         put_device(&cdev->dev);
920         put_device(&sch->dev);
921 }
922
923 /*
924  * subchannel recognition done. Called from the state machine.
925  */
926 void
927 io_subchannel_recog_done(struct ccw_device *cdev)
928 {
929         struct subchannel *sch;
930
931         if (css_init_done == 0) {
932                 cdev->private->flags.recog_done = 1;
933                 return;
934         }
935         switch (cdev->private->state) {
936         case DEV_STATE_NOT_OPER:
937                 cdev->private->flags.recog_done = 1;
938                 /* Remove device found not operational. */
939                 if (!get_device(&cdev->dev))
940                         break;
941                 sch = to_subchannel(cdev->dev.parent);
942                 PREPARE_WORK(&cdev->private->kick_work,
943                              ccw_device_call_sch_unregister);
944                 queue_work(slow_path_wq, &cdev->private->kick_work);
945                 if (atomic_dec_and_test(&ccw_device_init_count))
946                         wake_up(&ccw_device_init_wq);
947                 break;
948         case DEV_STATE_BOXED:
949                 /* Device did not respond in time. */
950         case DEV_STATE_OFFLINE:
951                 /* 
952                  * We can't register the device in interrupt context so
953                  * we schedule a work item.
954                  */
955                 if (!get_device(&cdev->dev))
956                         break;
957                 PREPARE_WORK(&cdev->private->kick_work,
958                              io_subchannel_register);
959                 queue_work(slow_path_wq, &cdev->private->kick_work);
960                 break;
961         }
962 }
963
964 static int
965 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
966 {
967         int rc;
968         struct ccw_device_private *priv;
969
970         sch->dev.driver_data = cdev;
971         sch->driver = &io_subchannel_driver;
972         cdev->ccwlock = sch->lock;
973
974         /* Init private data. */
975         priv = cdev->private;
976         priv->dev_id.devno = sch->schib.pmcw.dev;
977         priv->dev_id.ssid = sch->schid.ssid;
978         priv->schid = sch->schid;
979         priv->state = DEV_STATE_NOT_OPER;
980         INIT_LIST_HEAD(&priv->cmb_list);
981         init_waitqueue_head(&priv->wait_q);
982         init_timer(&priv->timer);
983
984         /* Set an initial name for the device. */
985         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
986                   sch->schid.ssid, sch->schib.pmcw.dev);
987
988         /* Increase counter of devices currently in recognition. */
989         atomic_inc(&ccw_device_init_count);
990
991         /* Start async. device sensing. */
992         spin_lock_irq(sch->lock);
993         rc = ccw_device_recognition(cdev);
994         spin_unlock_irq(sch->lock);
995         if (rc) {
996                 if (atomic_dec_and_test(&ccw_device_init_count))
997                         wake_up(&ccw_device_init_wq);
998         }
999         return rc;
1000 }
1001
1002 static void ccw_device_move_to_sch(struct work_struct *work)
1003 {
1004         struct ccw_device_private *priv;
1005         int rc;
1006         struct subchannel *sch;
1007         struct ccw_device *cdev;
1008         struct subchannel *former_parent;
1009
1010         priv = container_of(work, struct ccw_device_private, kick_work);
1011         sch = priv->sch;
1012         cdev = priv->cdev;
1013         former_parent = ccw_device_is_orphan(cdev) ?
1014                 NULL : to_subchannel(get_device(cdev->dev.parent));
1015         mutex_lock(&sch->reg_mutex);
1016         /* Try to move the ccw device to its new subchannel. */
1017         rc = device_move(&cdev->dev, &sch->dev);
1018         mutex_unlock(&sch->reg_mutex);
1019         if (rc) {
1020                 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1021                               "0.%x.%04x failed (ret=%d)!\n",
1022                               cdev->private->dev_id.ssid,
1023                               cdev->private->dev_id.devno, sch->schid.ssid,
1024                               sch->schid.sch_no, rc);
1025                 css_sch_device_unregister(sch);
1026                 goto out;
1027         }
1028         if (former_parent) {
1029                 spin_lock_irq(former_parent->lock);
1030                 former_parent->dev.driver_data = NULL;
1031                 spin_unlock_irq(former_parent->lock);
1032                 css_sch_device_unregister(former_parent);
1033                 /* Reset intparm to zeroes. */
1034                 former_parent->schib.pmcw.intparm = 0;
1035                 cio_modify(former_parent);
1036         }
1037         sch_attach_device(sch, cdev);
1038 out:
1039         if (former_parent)
1040                 put_device(&former_parent->dev);
1041         put_device(&cdev->dev);
1042 }
1043
1044 static int
1045 io_subchannel_probe (struct subchannel *sch)
1046 {
1047         struct ccw_device *cdev;
1048         int rc;
1049         unsigned long flags;
1050         struct ccw_dev_id dev_id;
1051
1052         if (sch->dev.driver_data) {
1053                 /*
1054                  * This subchannel already has an associated ccw_device.
1055                  * Register it and exit. This happens for all early
1056                  * device, e.g. the console.
1057                  */
1058                 cdev = sch->dev.driver_data;
1059                 device_initialize(&cdev->dev);
1060                 ccw_device_register(cdev);
1061                 /*
1062                  * Check if the device is already online. If it is
1063                  * the reference count needs to be corrected
1064                  * (see ccw_device_online and css_init_done for the
1065                  * ugly details).
1066                  */
1067                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1068                     cdev->private->state != DEV_STATE_OFFLINE &&
1069                     cdev->private->state != DEV_STATE_BOXED)
1070                         get_device(&cdev->dev);
1071                 return 0;
1072         }
1073         /*
1074          * First check if a fitting device may be found amongst the
1075          * disconnected devices or in the orphanage.
1076          */
1077         dev_id.devno = sch->schib.pmcw.dev;
1078         dev_id.ssid = sch->schid.ssid;
1079         cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1080         if (!cdev)
1081                 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1082                                                      &dev_id);
1083         if (cdev) {
1084                 /*
1085                  * Schedule moving the device until when we have a registered
1086                  * subchannel to move to and succeed the probe. We can
1087                  * unregister later again, when the probe is through.
1088                  */
1089                 cdev->private->sch = sch;
1090                 PREPARE_WORK(&cdev->private->kick_work,
1091                              ccw_device_move_to_sch);
1092                 queue_work(slow_path_wq, &cdev->private->kick_work);
1093                 return 0;
1094         }
1095         cdev = io_subchannel_create_ccwdev(sch);
1096         if (IS_ERR(cdev))
1097                 return PTR_ERR(cdev);
1098
1099         rc = io_subchannel_recog(cdev, sch);
1100         if (rc) {
1101                 spin_lock_irqsave(sch->lock, flags);
1102                 sch->dev.driver_data = NULL;
1103                 spin_unlock_irqrestore(sch->lock, flags);
1104                 if (cdev->dev.release)
1105                         cdev->dev.release(&cdev->dev);
1106         }
1107
1108         return rc;
1109 }
1110
1111 static int
1112 io_subchannel_remove (struct subchannel *sch)
1113 {
1114         struct ccw_device *cdev;
1115         unsigned long flags;
1116
1117         if (!sch->dev.driver_data)
1118                 return 0;
1119         cdev = sch->dev.driver_data;
1120         /* Set ccw device to not operational and drop reference. */
1121         spin_lock_irqsave(cdev->ccwlock, flags);
1122         sch->dev.driver_data = NULL;
1123         cdev->private->state = DEV_STATE_NOT_OPER;
1124         spin_unlock_irqrestore(cdev->ccwlock, flags);
1125         ccw_device_unregister(cdev);
1126         put_device(&cdev->dev);
1127         return 0;
1128 }
1129
1130 static int
1131 io_subchannel_notify(struct device *dev, int event)
1132 {
1133         struct ccw_device *cdev;
1134
1135         cdev = dev->driver_data;
1136         if (!cdev)
1137                 return 0;
1138         if (!cdev->drv)
1139                 return 0;
1140         if (!cdev->online)
1141                 return 0;
1142         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1143 }
1144
1145 static void
1146 io_subchannel_verify(struct device *dev)
1147 {
1148         struct ccw_device *cdev;
1149
1150         cdev = dev->driver_data;
1151         if (cdev)
1152                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1153 }
1154
1155 static void
1156 io_subchannel_ioterm(struct device *dev)
1157 {
1158         struct ccw_device *cdev;
1159
1160         cdev = dev->driver_data;
1161         if (!cdev)
1162                 return;
1163         /* Internal I/O will be retried by the interrupt handler. */
1164         if (cdev->private->flags.intretry)
1165                 return;
1166         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1167         if (cdev->handler)
1168                 cdev->handler(cdev, cdev->private->intparm,
1169                               ERR_PTR(-EIO));
1170 }
1171
1172 static void
1173 io_subchannel_shutdown(struct subchannel *sch)
1174 {
1175         struct ccw_device *cdev;
1176         int ret;
1177
1178         cdev = sch->dev.driver_data;
1179
1180         if (cio_is_console(sch->schid))
1181                 return;
1182         if (!sch->schib.pmcw.ena)
1183                 /* Nothing to do. */
1184                 return;
1185         ret = cio_disable_subchannel(sch);
1186         if (ret != -EBUSY)
1187                 /* Subchannel is disabled, we're done. */
1188                 return;
1189         cdev->private->state = DEV_STATE_QUIESCE;
1190         if (cdev->handler)
1191                 cdev->handler(cdev, cdev->private->intparm,
1192                               ERR_PTR(-EIO));
1193         ret = ccw_device_cancel_halt_clear(cdev);
1194         if (ret == -EBUSY) {
1195                 ccw_device_set_timeout(cdev, HZ/10);
1196                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1197         }
1198         cio_disable_subchannel(sch);
1199 }
1200
1201 #ifdef CONFIG_CCW_CONSOLE
1202 static struct ccw_device console_cdev;
1203 static struct ccw_device_private console_private;
1204 static int console_cdev_in_use;
1205
1206 static DEFINE_SPINLOCK(ccw_console_lock);
1207
1208 spinlock_t * cio_get_console_lock(void)
1209 {
1210         return &ccw_console_lock;
1211 }
1212
1213 static int
1214 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1215 {
1216         int rc;
1217
1218         /* Initialize the ccw_device structure. */
1219         cdev->dev.parent= &sch->dev;
1220         rc = io_subchannel_recog(cdev, sch);
1221         if (rc)
1222                 return rc;
1223
1224         /* Now wait for the async. recognition to come to an end. */
1225         spin_lock_irq(cdev->ccwlock);
1226         while (!dev_fsm_final_state(cdev))
1227                 wait_cons_dev();
1228         rc = -EIO;
1229         if (cdev->private->state != DEV_STATE_OFFLINE)
1230                 goto out_unlock;
1231         ccw_device_online(cdev);
1232         while (!dev_fsm_final_state(cdev))
1233                 wait_cons_dev();
1234         if (cdev->private->state != DEV_STATE_ONLINE)
1235                 goto out_unlock;
1236         rc = 0;
1237 out_unlock:
1238         spin_unlock_irq(cdev->ccwlock);
1239         return 0;
1240 }
1241
1242 struct ccw_device *
1243 ccw_device_probe_console(void)
1244 {
1245         struct subchannel *sch;
1246         int ret;
1247
1248         if (xchg(&console_cdev_in_use, 1) != 0)
1249                 return ERR_PTR(-EBUSY);
1250         sch = cio_probe_console();
1251         if (IS_ERR(sch)) {
1252                 console_cdev_in_use = 0;
1253                 return (void *) sch;
1254         }
1255         memset(&console_cdev, 0, sizeof(struct ccw_device));
1256         memset(&console_private, 0, sizeof(struct ccw_device_private));
1257         console_cdev.private = &console_private;
1258         console_private.cdev = &console_cdev;
1259         ret = ccw_device_console_enable(&console_cdev, sch);
1260         if (ret) {
1261                 cio_release_console();
1262                 console_cdev_in_use = 0;
1263                 return ERR_PTR(ret);
1264         }
1265         console_cdev.online = 1;
1266         return &console_cdev;
1267 }
1268 #endif
1269
1270 /*
1271  * get ccw_device matching the busid, but only if owned by cdrv
1272  */
1273 static int
1274 __ccwdev_check_busid(struct device *dev, void *id)
1275 {
1276         char *bus_id;
1277
1278         bus_id = id;
1279
1280         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1281 }
1282
1283
1284 struct ccw_device *
1285 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1286 {
1287         struct device *dev;
1288         struct device_driver *drv;
1289
1290         drv = get_driver(&cdrv->driver);
1291         if (!drv)
1292                 return NULL;
1293
1294         dev = driver_find_device(drv, NULL, (void *)bus_id,
1295                                  __ccwdev_check_busid);
1296         put_driver(drv);
1297
1298         return dev ? to_ccwdev(dev) : NULL;
1299 }
1300
1301 /************************** device driver handling ************************/
1302
1303 /* This is the implementation of the ccw_driver class. The probe, remove
1304  * and release methods are initially very similar to the device_driver
1305  * implementations, with the difference that they have ccw_device
1306  * arguments.
1307  *
1308  * A ccw driver also contains the information that is needed for
1309  * device matching.
1310  */
1311 static int
1312 ccw_device_probe (struct device *dev)
1313 {
1314         struct ccw_device *cdev = to_ccwdev(dev);
1315         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1316         int ret;
1317
1318         cdev->drv = cdrv; /* to let the driver call _set_online */
1319
1320         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1321
1322         if (ret) {
1323                 cdev->drv = NULL;
1324                 return ret;
1325         }
1326
1327         return 0;
1328 }
1329
1330 static int
1331 ccw_device_remove (struct device *dev)
1332 {
1333         struct ccw_device *cdev = to_ccwdev(dev);
1334         struct ccw_driver *cdrv = cdev->drv;
1335         int ret;
1336
1337         pr_debug("removing device %s\n", cdev->dev.bus_id);
1338         if (cdrv->remove)
1339                 cdrv->remove(cdev);
1340         if (cdev->online) {
1341                 cdev->online = 0;
1342                 spin_lock_irq(cdev->ccwlock);
1343                 ret = ccw_device_offline(cdev);
1344                 spin_unlock_irq(cdev->ccwlock);
1345                 if (ret == 0)
1346                         wait_event(cdev->private->wait_q,
1347                                    dev_fsm_final_state(cdev));
1348                 else
1349                         //FIXME: we can't fail!
1350                         pr_debug("ccw_device_offline returned %d, device %s\n",
1351                                  ret, cdev->dev.bus_id);
1352         }
1353         ccw_device_set_timeout(cdev, 0);
1354         cdev->drv = NULL;
1355         return 0;
1356 }
1357
1358 struct bus_type ccw_bus_type = {
1359         .name   = "ccw",
1360         .match  = ccw_bus_match,
1361         .uevent = ccw_uevent,
1362         .probe  = ccw_device_probe,
1363         .remove = ccw_device_remove,
1364 };
1365
1366 int
1367 ccw_driver_register (struct ccw_driver *cdriver)
1368 {
1369         struct device_driver *drv = &cdriver->driver;
1370
1371         drv->bus = &ccw_bus_type;
1372         drv->name = cdriver->name;
1373
1374         return driver_register(drv);
1375 }
1376
1377 void
1378 ccw_driver_unregister (struct ccw_driver *cdriver)
1379 {
1380         driver_unregister(&cdriver->driver);
1381 }
1382
1383 /* Helper func for qdio. */
1384 struct subchannel_id
1385 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1386 {
1387         struct subchannel *sch;
1388
1389         sch = to_subchannel(cdev->dev.parent);
1390         return sch->schid;
1391 }
1392
1393 MODULE_LICENSE("GPL");
1394 EXPORT_SYMBOL(ccw_device_set_online);
1395 EXPORT_SYMBOL(ccw_device_set_offline);
1396 EXPORT_SYMBOL(ccw_driver_register);
1397 EXPORT_SYMBOL(ccw_driver_unregister);
1398 EXPORT_SYMBOL(get_ccwdev_by_busid);
1399 EXPORT_SYMBOL(ccw_bus_type);
1400 EXPORT_SYMBOL(ccw_device_work);
1401 EXPORT_SYMBOL(ccw_device_notify_work);
1402 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);