Merge master.kernel.org:/pub/scm/linux/kernel/git/davej/agpgart
[linux-2.6] / drivers / s390 / cio / device.c
1 /*
2  *  drivers/s390/cio/device.c
3  *  bus driver for ccw devices
4  *   $Revision: 1.131 $
5  *
6  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
7  *                       IBM Corporation
8  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
9  *               Cornelia Huck (cohuck@de.ibm.com)
10  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
11  */
12 #include <linux/config.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/slab.h>
19 #include <linux/list.h>
20 #include <linux/device.h>
21 #include <linux/workqueue.h>
22
23 #include <asm/ccwdev.h>
24 #include <asm/cio.h>
25 #include <asm/param.h>          /* HZ */
26
27 #include "cio.h"
28 #include "css.h"
29 #include "device.h"
30 #include "ioasm.h"
31
32 /******************* bus type handling ***********************/
33
34 /* The Linux driver model distinguishes between a bus type and
35  * the bus itself. Of course we only have one channel
36  * subsystem driver and one channel system per machine, but
37  * we still use the abstraction. T.R. says it's a good idea. */
38 static int
39 ccw_bus_match (struct device * dev, struct device_driver * drv)
40 {
41         struct ccw_device *cdev = to_ccwdev(dev);
42         struct ccw_driver *cdrv = to_ccwdrv(drv);
43         const struct ccw_device_id *ids = cdrv->ids, *found;
44
45         if (!ids)
46                 return 0;
47
48         found = ccw_device_id_match(ids, &cdev->id);
49         if (!found)
50                 return 0;
51
52         cdev->id.driver_info = found->driver_info;
53
54         return 1;
55 }
56
57 /*
58  * Hotplugging interface for ccw devices.
59  * Heavily modeled on pci and usb hotplug.
60  */
61 static int
62 ccw_hotplug (struct device *dev, char **envp, int num_envp,
63              char *buffer, int buffer_size)
64 {
65         struct ccw_device *cdev = to_ccwdev(dev);
66         int i = 0;
67         int length = 0;
68
69         if (!cdev)
70                 return -ENODEV;
71
72         /* what we want to pass to /sbin/hotplug */
73
74         envp[i++] = buffer;
75         length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
76                            cdev->id.cu_type);
77         if ((buffer_size - length <= 0) || (i >= num_envp))
78                 return -ENOMEM;
79         ++length;
80         buffer += length;
81
82         envp[i++] = buffer;
83         length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
84                            cdev->id.cu_model);
85         if ((buffer_size - length <= 0) || (i >= num_envp))
86                 return -ENOMEM;
87         ++length;
88         buffer += length;
89
90         /* The next two can be zero, that's ok for us */
91         envp[i++] = buffer;
92         length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
93                            cdev->id.dev_type);
94         if ((buffer_size - length <= 0) || (i >= num_envp))
95                 return -ENOMEM;
96         ++length;
97         buffer += length;
98
99         envp[i++] = buffer;
100         length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
101                            cdev->id.dev_model);
102         if ((buffer_size - length <= 0) || (i >= num_envp))
103                 return -ENOMEM;
104
105         envp[i] = 0;
106
107         return 0;
108 }
109
110 struct bus_type ccw_bus_type = {
111         .name  = "ccw",
112         .match = &ccw_bus_match,
113         .hotplug = &ccw_hotplug,
114 };
115
116 static int io_subchannel_probe (struct device *);
117 static int io_subchannel_remove (struct device *);
118 void io_subchannel_irq (struct device *);
119 static int io_subchannel_notify(struct device *, int);
120 static void io_subchannel_verify(struct device *);
121 static void io_subchannel_ioterm(struct device *);
122 static void io_subchannel_shutdown(struct device *);
123
124 struct css_driver io_subchannel_driver = {
125         .subchannel_type = SUBCHANNEL_TYPE_IO,
126         .drv = {
127                 .name = "io_subchannel",
128                 .bus  = &css_bus_type,
129                 .probe = &io_subchannel_probe,
130                 .remove = &io_subchannel_remove,
131                 .shutdown = &io_subchannel_shutdown,
132         },
133         .irq = io_subchannel_irq,
134         .notify = io_subchannel_notify,
135         .verify = io_subchannel_verify,
136         .termination = io_subchannel_ioterm,
137 };
138
139 struct workqueue_struct *ccw_device_work;
140 struct workqueue_struct *ccw_device_notify_work;
141 static wait_queue_head_t ccw_device_init_wq;
142 static atomic_t ccw_device_init_count;
143
144 static int __init
145 init_ccw_bus_type (void)
146 {
147         int ret;
148
149         init_waitqueue_head(&ccw_device_init_wq);
150         atomic_set(&ccw_device_init_count, 0);
151
152         ccw_device_work = create_singlethread_workqueue("cio");
153         if (!ccw_device_work)
154                 return -ENOMEM; /* FIXME: better errno ? */
155         ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
156         if (!ccw_device_notify_work) {
157                 ret = -ENOMEM; /* FIXME: better errno ? */
158                 goto out_err;
159         }
160         slow_path_wq = create_singlethread_workqueue("kslowcrw");
161         if (!slow_path_wq) {
162                 ret = -ENOMEM; /* FIXME: better errno ? */
163                 goto out_err;
164         }
165         if ((ret = bus_register (&ccw_bus_type)))
166                 goto out_err;
167
168         if ((ret = driver_register(&io_subchannel_driver.drv)))
169                 goto out_err;
170
171         wait_event(ccw_device_init_wq,
172                    atomic_read(&ccw_device_init_count) == 0);
173         flush_workqueue(ccw_device_work);
174         return 0;
175 out_err:
176         if (ccw_device_work)
177                 destroy_workqueue(ccw_device_work);
178         if (ccw_device_notify_work)
179                 destroy_workqueue(ccw_device_notify_work);
180         if (slow_path_wq)
181                 destroy_workqueue(slow_path_wq);
182         return ret;
183 }
184
185 static void __exit
186 cleanup_ccw_bus_type (void)
187 {
188         driver_unregister(&io_subchannel_driver.drv);
189         bus_unregister(&ccw_bus_type);
190         destroy_workqueue(ccw_device_notify_work);
191         destroy_workqueue(ccw_device_work);
192 }
193
194 subsys_initcall(init_ccw_bus_type);
195 module_exit(cleanup_ccw_bus_type);
196
197 /************************ device handling **************************/
198
199 /*
200  * A ccw_device has some interfaces in sysfs in addition to the
201  * standard ones.
202  * The following entries are designed to export the information which
203  * resided in 2.4 in /proc/subchannels. Subchannel and device number
204  * are obvious, so they don't have an entry :)
205  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
206  */
207 static ssize_t
208 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
209 {
210         struct subchannel *sch = to_subchannel(dev);
211         struct ssd_info *ssd = &sch->ssd_info;
212         ssize_t ret = 0;
213         int chp;
214
215         for (chp = 0; chp < 8; chp++)
216                 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
217
218         ret += sprintf (buf+ret, "\n");
219         return min((ssize_t)PAGE_SIZE, ret);
220 }
221
222 static ssize_t
223 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
224 {
225         struct subchannel *sch = to_subchannel(dev);
226         struct pmcw *pmcw = &sch->schib.pmcw;
227
228         return sprintf (buf, "%02x %02x %02x\n",
229                         pmcw->pim, pmcw->pam, pmcw->pom);
230 }
231
232 static ssize_t
233 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
234 {
235         struct ccw_device *cdev = to_ccwdev(dev);
236         struct ccw_device_id *id = &(cdev->id);
237
238         if (id->dev_type != 0)
239                 return sprintf(buf, "%04x/%02x\n",
240                                 id->dev_type, id->dev_model);
241         else
242                 return sprintf(buf, "n/a\n");
243 }
244
245 static ssize_t
246 cutype_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         return sprintf(buf, "%04x/%02x\n",
252                        id->cu_type, id->cu_model);
253 }
254
255 static ssize_t
256 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
257 {
258         struct ccw_device *cdev = to_ccwdev(dev);
259         struct ccw_device_id *id = &(cdev->id);
260         int ret;
261
262         ret = sprintf(buf, "ccw:t%04Xm%02x",
263                         id->cu_type, id->cu_model);
264         if (id->dev_type != 0)
265                 ret += sprintf(buf + ret, "dt%04Xdm%02X\n",
266                                 id->dev_type, id->dev_model);
267         else
268                 ret += sprintf(buf + ret, "dtdm\n");
269         return ret;
270 }
271
272 static ssize_t
273 online_show (struct device *dev, struct device_attribute *attr, char *buf)
274 {
275         struct ccw_device *cdev = to_ccwdev(dev);
276
277         return sprintf(buf, cdev->online ? "1\n" : "0\n");
278 }
279
280 static void
281 ccw_device_remove_disconnected(struct ccw_device *cdev)
282 {
283         struct subchannel *sch;
284         /*
285          * Forced offline in disconnected state means
286          * 'throw away device'.
287          */
288         sch = to_subchannel(cdev->dev.parent);
289         device_unregister(&sch->dev);
290         /* Reset intparm to zeroes. */
291         sch->schib.pmcw.intparm = 0;
292         cio_modify(sch);
293         put_device(&sch->dev);
294 }
295
296 int
297 ccw_device_set_offline(struct ccw_device *cdev)
298 {
299         int ret;
300
301         if (!cdev)
302                 return -ENODEV;
303         if (!cdev->online || !cdev->drv)
304                 return -EINVAL;
305
306         if (cdev->drv->set_offline) {
307                 ret = cdev->drv->set_offline(cdev);
308                 if (ret != 0)
309                         return ret;
310         }
311         cdev->online = 0;
312         spin_lock_irq(cdev->ccwlock);
313         ret = ccw_device_offline(cdev);
314         if (ret == -ENODEV) {
315                 if (cdev->private->state != DEV_STATE_NOT_OPER) {
316                         cdev->private->state = DEV_STATE_OFFLINE;
317                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
318                 }
319                 spin_unlock_irq(cdev->ccwlock);
320                 return ret;
321         }
322         spin_unlock_irq(cdev->ccwlock);
323         if (ret == 0)
324                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
325         else {
326                 pr_debug("ccw_device_offline returned %d, device %s\n",
327                          ret, cdev->dev.bus_id);
328                 cdev->online = 1;
329         }
330         return ret;
331 }
332
333 int
334 ccw_device_set_online(struct ccw_device *cdev)
335 {
336         int ret;
337
338         if (!cdev)
339                 return -ENODEV;
340         if (cdev->online || !cdev->drv)
341                 return -EINVAL;
342
343         spin_lock_irq(cdev->ccwlock);
344         ret = ccw_device_online(cdev);
345         spin_unlock_irq(cdev->ccwlock);
346         if (ret == 0)
347                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
348         else {
349                 pr_debug("ccw_device_online returned %d, device %s\n",
350                          ret, cdev->dev.bus_id);
351                 return ret;
352         }
353         if (cdev->private->state != DEV_STATE_ONLINE)
354                 return -ENODEV;
355         if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
356                 cdev->online = 1;
357                 return 0;
358         }
359         spin_lock_irq(cdev->ccwlock);
360         ret = ccw_device_offline(cdev);
361         spin_unlock_irq(cdev->ccwlock);
362         if (ret == 0)
363                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
364         else 
365                 pr_debug("ccw_device_offline returned %d, device %s\n",
366                          ret, cdev->dev.bus_id);
367         return (ret = 0) ? -ENODEV : ret;
368 }
369
370 static ssize_t
371 online_store (struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
372 {
373         struct ccw_device *cdev = to_ccwdev(dev);
374         int i, force, ret;
375         char *tmp;
376
377         if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
378                 return -EAGAIN;
379
380         if (cdev->drv && !try_module_get(cdev->drv->owner)) {
381                 atomic_set(&cdev->private->onoff, 0);
382                 return -EINVAL;
383         }
384         if (!strncmp(buf, "force\n", count)) {
385                 force = 1;
386                 i = 1;
387         } else {
388                 force = 0;
389                 i = simple_strtoul(buf, &tmp, 16);
390         }
391         if (i == 1) {
392                 /* Do device recognition, if needed. */
393                 if (cdev->id.cu_type == 0) {
394                         ret = ccw_device_recognition(cdev);
395                         if (ret) {
396                                 printk(KERN_WARNING"Couldn't start recognition "
397                                        "for device %s (ret=%d)\n",
398                                        cdev->dev.bus_id, ret);
399                                 goto out;
400                         }
401                         wait_event(cdev->private->wait_q,
402                                    cdev->private->flags.recog_done);
403                 }
404                 if (cdev->drv && cdev->drv->set_online)
405                         ccw_device_set_online(cdev);
406         } else if (i == 0) {
407                 if (cdev->private->state == DEV_STATE_DISCONNECTED)
408                         ccw_device_remove_disconnected(cdev);
409                 else if (cdev->drv && cdev->drv->set_offline)
410                         ccw_device_set_offline(cdev);
411         }
412         if (force && cdev->private->state == DEV_STATE_BOXED) {
413                 ret = ccw_device_stlck(cdev);
414                 if (ret) {
415                         printk(KERN_WARNING"ccw_device_stlck for device %s "
416                                "returned %d!\n", cdev->dev.bus_id, ret);
417                         goto out;
418                 }
419                 /* Do device recognition, if needed. */
420                 if (cdev->id.cu_type == 0) {
421                         cdev->private->state = DEV_STATE_NOT_OPER;
422                         ret = ccw_device_recognition(cdev);
423                         if (ret) {
424                                 printk(KERN_WARNING"Couldn't start recognition "
425                                        "for device %s (ret=%d)\n",
426                                        cdev->dev.bus_id, ret);
427                                 goto out;
428                         }
429                         wait_event(cdev->private->wait_q,
430                                    cdev->private->flags.recog_done);
431                 }
432                 if (cdev->drv && cdev->drv->set_online)
433                         ccw_device_set_online(cdev);
434         }
435         out:
436         if (cdev->drv)
437                 module_put(cdev->drv->owner);
438         atomic_set(&cdev->private->onoff, 0);
439         return count;
440 }
441
442 static ssize_t
443 available_show (struct device *dev, struct device_attribute *attr, char *buf)
444 {
445         struct ccw_device *cdev = to_ccwdev(dev);
446         struct subchannel *sch;
447
448         switch (cdev->private->state) {
449         case DEV_STATE_BOXED:
450                 return sprintf(buf, "boxed\n");
451         case DEV_STATE_DISCONNECTED:
452         case DEV_STATE_DISCONNECTED_SENSE_ID:
453         case DEV_STATE_NOT_OPER:
454                 sch = to_subchannel(dev->parent);
455                 if (!sch->lpm)
456                         return sprintf(buf, "no path\n");
457                 else
458                         return sprintf(buf, "no device\n");
459         default:
460                 /* All other states considered fine. */
461                 return sprintf(buf, "good\n");
462         }
463 }
464
465 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
466 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
467 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
468 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
469 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
470 static DEVICE_ATTR(online, 0644, online_show, online_store);
471 extern struct device_attribute dev_attr_cmb_enable;
472 static DEVICE_ATTR(availability, 0444, available_show, NULL);
473
474 static struct attribute * subch_attrs[] = {
475         &dev_attr_chpids.attr,
476         &dev_attr_pimpampom.attr,
477         NULL,
478 };
479
480 static struct attribute_group subch_attr_group = {
481         .attrs = subch_attrs,
482 };
483
484 static inline int
485 subchannel_add_files (struct device *dev)
486 {
487         return sysfs_create_group(&dev->kobj, &subch_attr_group);
488 }
489
490 static struct attribute * ccwdev_attrs[] = {
491         &dev_attr_devtype.attr,
492         &dev_attr_cutype.attr,
493         &dev_attr_modalias.attr,
494         &dev_attr_online.attr,
495         &dev_attr_cmb_enable.attr,
496         &dev_attr_availability.attr,
497         NULL,
498 };
499
500 static struct attribute_group ccwdev_attr_group = {
501         .attrs = ccwdev_attrs,
502 };
503
504 static inline int
505 device_add_files (struct device *dev)
506 {
507         return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
508 }
509
510 static inline void
511 device_remove_files(struct device *dev)
512 {
513         sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
514 }
515
516 /* this is a simple abstraction for device_register that sets the
517  * correct bus type and adds the bus specific files */
518 int
519 ccw_device_register(struct ccw_device *cdev)
520 {
521         struct device *dev = &cdev->dev;
522         int ret;
523
524         dev->bus = &ccw_bus_type;
525
526         if ((ret = device_add(dev)))
527                 return ret;
528
529         set_bit(1, &cdev->private->registered);
530         if ((ret = device_add_files(dev))) {
531                 if (test_and_clear_bit(1, &cdev->private->registered))
532                         device_del(dev);
533         }
534         return ret;
535 }
536
537 struct match_data {
538         unsigned int  devno;
539         struct ccw_device * sibling;
540 };
541
542 static int
543 match_devno(struct device * dev, void * data)
544 {
545         struct match_data * d = (struct match_data *)data;
546         struct ccw_device * cdev;
547
548         cdev = to_ccwdev(dev);
549         if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
550             (cdev->private->devno == d->devno) &&
551             (cdev != d->sibling)) {
552                 cdev->private->state = DEV_STATE_NOT_OPER;
553                 return 1;
554         }
555         return 0;
556 }
557
558 static struct ccw_device *
559 get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
560 {
561         struct device *dev;
562         struct match_data data = {
563                 .devno  = devno,
564                 .sibling = sibling,
565         };
566
567         dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
568
569         return dev ? to_ccwdev(dev) : NULL;
570 }
571
572 static void
573 ccw_device_add_changed(void *data)
574 {
575
576         struct ccw_device *cdev;
577
578         cdev = (struct ccw_device *)data;
579         if (device_add(&cdev->dev)) {
580                 put_device(&cdev->dev);
581                 return;
582         }
583         set_bit(1, &cdev->private->registered);
584         if (device_add_files(&cdev->dev)) {
585                 if (test_and_clear_bit(1, &cdev->private->registered))
586                         device_unregister(&cdev->dev);
587         }
588 }
589
590 extern int css_get_ssd_info(struct subchannel *sch);
591
592 void
593 ccw_device_do_unreg_rereg(void *data)
594 {
595         struct ccw_device *cdev;
596         struct subchannel *sch;
597         int need_rename;
598
599         cdev = (struct ccw_device *)data;
600         sch = to_subchannel(cdev->dev.parent);
601         if (cdev->private->devno != sch->schib.pmcw.dev) {
602                 /*
603                  * The device number has changed. This is usually only when
604                  * a device has been detached under VM and then re-appeared
605                  * on another subchannel because of a different attachment
606                  * order than before. Ideally, we should should just switch
607                  * subchannels, but unfortunately, this is not possible with
608                  * the current implementation.
609                  * Instead, we search for the old subchannel for this device
610                  * number and deregister so there are no collisions with the
611                  * newly registered ccw_device.
612                  * FIXME: Find another solution so the block layer doesn't
613                  *        get possibly sick...
614                  */
615                 struct ccw_device *other_cdev;
616
617                 need_rename = 1;
618                 other_cdev = get_disc_ccwdev_by_devno(sch->schib.pmcw.dev,
619                                                       cdev);
620                 if (other_cdev) {
621                         struct subchannel *other_sch;
622
623                         other_sch = to_subchannel(other_cdev->dev.parent);
624                         if (get_device(&other_sch->dev)) {
625                                 stsch(other_sch->irq, &other_sch->schib);
626                                 if (other_sch->schib.pmcw.dnv) {
627                                         other_sch->schib.pmcw.intparm = 0;
628                                         cio_modify(other_sch);
629                                 }
630                                 device_unregister(&other_sch->dev);
631                         }
632                 }
633                 /* Update ssd info here. */
634                 css_get_ssd_info(sch);
635                 cdev->private->devno = sch->schib.pmcw.dev;
636         } else
637                 need_rename = 0;
638         device_remove_files(&cdev->dev);
639         if (test_and_clear_bit(1, &cdev->private->registered))
640                 device_del(&cdev->dev);
641         if (need_rename)
642                 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
643                           sch->schib.pmcw.dev);
644         PREPARE_WORK(&cdev->private->kick_work,
645                      ccw_device_add_changed, (void *)cdev);
646         queue_work(ccw_device_work, &cdev->private->kick_work);
647 }
648
649 static void
650 ccw_device_release(struct device *dev)
651 {
652         struct ccw_device *cdev;
653
654         cdev = to_ccwdev(dev);
655         kfree(cdev->private);
656         kfree(cdev);
657 }
658
659 /*
660  * Register recognized device.
661  */
662 static void
663 io_subchannel_register(void *data)
664 {
665         struct ccw_device *cdev;
666         struct subchannel *sch;
667         int ret;
668         unsigned long flags;
669
670         cdev = (struct ccw_device *) data;
671         sch = to_subchannel(cdev->dev.parent);
672
673         if (klist_node_attached(&cdev->dev.knode_parent)) {
674                 bus_rescan_devices(&ccw_bus_type);
675                 goto out;
676         }
677         /* make it known to the system */
678         ret = ccw_device_register(cdev);
679         if (ret) {
680                 printk (KERN_WARNING "%s: could not register %s\n",
681                         __func__, cdev->dev.bus_id);
682                 put_device(&cdev->dev);
683                 spin_lock_irqsave(&sch->lock, flags);
684                 sch->dev.driver_data = NULL;
685                 spin_unlock_irqrestore(&sch->lock, flags);
686                 kfree (cdev->private);
687                 kfree (cdev);
688                 put_device(&sch->dev);
689                 if (atomic_dec_and_test(&ccw_device_init_count))
690                         wake_up(&ccw_device_init_wq);
691                 return;
692         }
693
694         ret = subchannel_add_files(cdev->dev.parent);
695         if (ret)
696                 printk(KERN_WARNING "%s: could not add attributes to %s\n",
697                        __func__, sch->dev.bus_id);
698         put_device(&cdev->dev);
699 out:
700         cdev->private->flags.recog_done = 1;
701         put_device(&sch->dev);
702         wake_up(&cdev->private->wait_q);
703         if (atomic_dec_and_test(&ccw_device_init_count))
704                 wake_up(&ccw_device_init_wq);
705 }
706
707 void
708 ccw_device_call_sch_unregister(void *data)
709 {
710         struct ccw_device *cdev = data;
711         struct subchannel *sch;
712
713         sch = to_subchannel(cdev->dev.parent);
714         device_unregister(&sch->dev);
715         /* Reset intparm to zeroes. */
716         sch->schib.pmcw.intparm = 0;
717         cio_modify(sch);
718         put_device(&cdev->dev);
719         put_device(&sch->dev);
720 }
721
722 /*
723  * subchannel recognition done. Called from the state machine.
724  */
725 void
726 io_subchannel_recog_done(struct ccw_device *cdev)
727 {
728         struct subchannel *sch;
729
730         if (css_init_done == 0) {
731                 cdev->private->flags.recog_done = 1;
732                 return;
733         }
734         switch (cdev->private->state) {
735         case DEV_STATE_NOT_OPER:
736                 cdev->private->flags.recog_done = 1;
737                 /* Remove device found not operational. */
738                 if (!get_device(&cdev->dev))
739                         break;
740                 sch = to_subchannel(cdev->dev.parent);
741                 PREPARE_WORK(&cdev->private->kick_work,
742                              ccw_device_call_sch_unregister, (void *) cdev);
743                 queue_work(slow_path_wq, &cdev->private->kick_work);
744                 if (atomic_dec_and_test(&ccw_device_init_count))
745                         wake_up(&ccw_device_init_wq);
746                 break;
747         case DEV_STATE_BOXED:
748                 /* Device did not respond in time. */
749         case DEV_STATE_OFFLINE:
750                 /* 
751                  * We can't register the device in interrupt context so
752                  * we schedule a work item.
753                  */
754                 if (!get_device(&cdev->dev))
755                         break;
756                 PREPARE_WORK(&cdev->private->kick_work,
757                              io_subchannel_register, (void *) cdev);
758                 queue_work(slow_path_wq, &cdev->private->kick_work);
759                 break;
760         }
761 }
762
763 static int
764 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
765 {
766         int rc;
767         struct ccw_device_private *priv;
768
769         sch->dev.driver_data = cdev;
770         sch->driver = &io_subchannel_driver;
771         cdev->ccwlock = &sch->lock;
772         /* Init private data. */
773         priv = cdev->private;
774         priv->devno = sch->schib.pmcw.dev;
775         priv->irq = sch->irq;
776         priv->state = DEV_STATE_NOT_OPER;
777         INIT_LIST_HEAD(&priv->cmb_list);
778         init_waitqueue_head(&priv->wait_q);
779         init_timer(&priv->timer);
780
781         /* Set an initial name for the device. */
782         snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
783                   sch->schib.pmcw.dev);
784
785         /* Increase counter of devices currently in recognition. */
786         atomic_inc(&ccw_device_init_count);
787
788         /* Start async. device sensing. */
789         spin_lock_irq(&sch->lock);
790         rc = ccw_device_recognition(cdev);
791         spin_unlock_irq(&sch->lock);
792         if (rc) {
793                 if (atomic_dec_and_test(&ccw_device_init_count))
794                         wake_up(&ccw_device_init_wq);
795         }
796         return rc;
797 }
798
799 static int
800 io_subchannel_probe (struct device *pdev)
801 {
802         struct subchannel *sch;
803         struct ccw_device *cdev;
804         int rc;
805         unsigned long flags;
806
807         sch = to_subchannel(pdev);
808         if (sch->dev.driver_data) {
809                 /*
810                  * This subchannel already has an associated ccw_device.
811                  * Register it and exit. This happens for all early
812                  * device, e.g. the console.
813                  */
814                 cdev = sch->dev.driver_data;
815                 device_initialize(&cdev->dev);
816                 ccw_device_register(cdev);
817                 subchannel_add_files(&sch->dev);
818                 /*
819                  * Check if the device is already online. If it is
820                  * the reference count needs to be corrected
821                  * (see ccw_device_online and css_init_done for the
822                  * ugly details).
823                  */
824                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
825                     cdev->private->state != DEV_STATE_OFFLINE &&
826                     cdev->private->state != DEV_STATE_BOXED)
827                         get_device(&cdev->dev);
828                 return 0;
829         }
830         cdev  = kmalloc (sizeof(*cdev), GFP_KERNEL);
831         if (!cdev)
832                 return -ENOMEM;
833         memset(cdev, 0, sizeof(struct ccw_device));
834         cdev->private = kmalloc(sizeof(struct ccw_device_private), 
835                                 GFP_KERNEL | GFP_DMA);
836         if (!cdev->private) {
837                 kfree(cdev);
838                 return -ENOMEM;
839         }
840         memset(cdev->private, 0, sizeof(struct ccw_device_private));
841         atomic_set(&cdev->private->onoff, 0);
842         cdev->dev = (struct device) {
843                 .parent = pdev,
844                 .release = ccw_device_release,
845         };
846         INIT_LIST_HEAD(&cdev->private->kick_work.entry);
847         /* Do first half of device_register. */
848         device_initialize(&cdev->dev);
849
850         if (!get_device(&sch->dev)) {
851                 if (cdev->dev.release)
852                         cdev->dev.release(&cdev->dev);
853                 return -ENODEV;
854         }
855
856         rc = io_subchannel_recog(cdev, to_subchannel(pdev));
857         if (rc) {
858                 spin_lock_irqsave(&sch->lock, flags);
859                 sch->dev.driver_data = NULL;
860                 spin_unlock_irqrestore(&sch->lock, flags);
861                 if (cdev->dev.release)
862                         cdev->dev.release(&cdev->dev);
863         }
864
865         return rc;
866 }
867
868 static void
869 ccw_device_unregister(void *data)
870 {
871         struct ccw_device *cdev;
872
873         cdev = (struct ccw_device *)data;
874         if (test_and_clear_bit(1, &cdev->private->registered))
875                 device_unregister(&cdev->dev);
876         put_device(&cdev->dev);
877 }
878
879 static int
880 io_subchannel_remove (struct device *dev)
881 {
882         struct ccw_device *cdev;
883         unsigned long flags;
884
885         if (!dev->driver_data)
886                 return 0;
887         cdev = dev->driver_data;
888         /* Set ccw device to not operational and drop reference. */
889         spin_lock_irqsave(cdev->ccwlock, flags);
890         dev->driver_data = NULL;
891         cdev->private->state = DEV_STATE_NOT_OPER;
892         spin_unlock_irqrestore(cdev->ccwlock, flags);
893         /*
894          * Put unregistration on workqueue to avoid livelocks on the css bus
895          * semaphore.
896          */
897         if (get_device(&cdev->dev)) {
898                 PREPARE_WORK(&cdev->private->kick_work,
899                              ccw_device_unregister, (void *) cdev);
900                 queue_work(ccw_device_work, &cdev->private->kick_work);
901         }
902         return 0;
903 }
904
905 static int
906 io_subchannel_notify(struct device *dev, int event)
907 {
908         struct ccw_device *cdev;
909
910         cdev = dev->driver_data;
911         if (!cdev)
912                 return 0;
913         if (!cdev->drv)
914                 return 0;
915         if (!cdev->online)
916                 return 0;
917         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
918 }
919
920 static void
921 io_subchannel_verify(struct device *dev)
922 {
923         struct ccw_device *cdev;
924
925         cdev = dev->driver_data;
926         if (cdev)
927                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
928 }
929
930 static void
931 io_subchannel_ioterm(struct device *dev)
932 {
933         struct ccw_device *cdev;
934
935         cdev = dev->driver_data;
936         if (!cdev)
937                 return;
938         cdev->private->state = DEV_STATE_CLEAR_VERIFY;
939         if (cdev->handler)
940                 cdev->handler(cdev, cdev->private->intparm,
941                               ERR_PTR(-EIO));
942 }
943
944 static void
945 io_subchannel_shutdown(struct device *dev)
946 {
947         struct subchannel *sch;
948         struct ccw_device *cdev;
949         int ret;
950
951         sch = to_subchannel(dev);
952         cdev = dev->driver_data;
953
954         if (cio_is_console(sch->irq))
955                 return;
956         if (!sch->schib.pmcw.ena)
957                 /* Nothing to do. */
958                 return;
959         ret = cio_disable_subchannel(sch);
960         if (ret != -EBUSY)
961                 /* Subchannel is disabled, we're done. */
962                 return;
963         cdev->private->state = DEV_STATE_QUIESCE;
964         if (cdev->handler)
965                 cdev->handler(cdev, cdev->private->intparm,
966                               ERR_PTR(-EIO));
967         ret = ccw_device_cancel_halt_clear(cdev);
968         if (ret == -EBUSY) {
969                 ccw_device_set_timeout(cdev, HZ/10);
970                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
971         }
972         cio_disable_subchannel(sch);
973 }
974
975 #ifdef CONFIG_CCW_CONSOLE
976 static struct ccw_device console_cdev;
977 static struct ccw_device_private console_private;
978 static int console_cdev_in_use;
979
980 static int
981 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
982 {
983         int rc;
984
985         /* Initialize the ccw_device structure. */
986         cdev->dev = (struct device) {
987                 .parent = &sch->dev,
988         };
989         /* Initialize the subchannel structure */
990         sch->dev.parent = &css_bus_device;
991         sch->dev.bus = &css_bus_type;
992
993         rc = io_subchannel_recog(cdev, sch);
994         if (rc)
995                 return rc;
996
997         /* Now wait for the async. recognition to come to an end. */
998         spin_lock_irq(cdev->ccwlock);
999         while (!dev_fsm_final_state(cdev))
1000                 wait_cons_dev();
1001         rc = -EIO;
1002         if (cdev->private->state != DEV_STATE_OFFLINE)
1003                 goto out_unlock;
1004         ccw_device_online(cdev);
1005         while (!dev_fsm_final_state(cdev))
1006                 wait_cons_dev();
1007         if (cdev->private->state != DEV_STATE_ONLINE)
1008                 goto out_unlock;
1009         rc = 0;
1010 out_unlock:
1011         spin_unlock_irq(cdev->ccwlock);
1012         return 0;
1013 }
1014
1015 struct ccw_device *
1016 ccw_device_probe_console(void)
1017 {
1018         struct subchannel *sch;
1019         int ret;
1020
1021         if (xchg(&console_cdev_in_use, 1) != 0)
1022                 return NULL;
1023         sch = cio_probe_console();
1024         if (IS_ERR(sch)) {
1025                 console_cdev_in_use = 0;
1026                 return (void *) sch;
1027         }
1028         memset(&console_cdev, 0, sizeof(struct ccw_device));
1029         memset(&console_private, 0, sizeof(struct ccw_device_private));
1030         console_cdev.private = &console_private;
1031         ret = ccw_device_console_enable(&console_cdev, sch);
1032         if (ret) {
1033                 cio_release_console();
1034                 console_cdev_in_use = 0;
1035                 return ERR_PTR(ret);
1036         }
1037         console_cdev.online = 1;
1038         return &console_cdev;
1039 }
1040 #endif
1041
1042 /*
1043  * get ccw_device matching the busid, but only if owned by cdrv
1044  */
1045 static int
1046 __ccwdev_check_busid(struct device *dev, void *id)
1047 {
1048         char *bus_id;
1049
1050         bus_id = (char *)id;
1051
1052         return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1053 }
1054
1055
1056 struct ccw_device *
1057 get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1058 {
1059         struct device *dev;
1060         struct device_driver *drv;
1061
1062         drv = get_driver(&cdrv->driver);
1063         if (!drv)
1064                 return NULL;
1065
1066         dev = driver_find_device(drv, NULL, (void *)bus_id,
1067                                  __ccwdev_check_busid);
1068         put_driver(drv);
1069
1070         return dev ? to_ccwdev(dev) : 0;
1071 }
1072
1073 /************************** device driver handling ************************/
1074
1075 /* This is the implementation of the ccw_driver class. The probe, remove
1076  * and release methods are initially very similar to the device_driver
1077  * implementations, with the difference that they have ccw_device
1078  * arguments.
1079  *
1080  * A ccw driver also contains the information that is needed for
1081  * device matching.
1082  */
1083 static int
1084 ccw_device_probe (struct device *dev)
1085 {
1086         struct ccw_device *cdev = to_ccwdev(dev);
1087         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1088         int ret;
1089
1090         cdev->drv = cdrv; /* to let the driver call _set_online */
1091
1092         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1093
1094         if (ret) {
1095                 cdev->drv = 0;
1096                 return ret;
1097         }
1098
1099         return 0;
1100 }
1101
1102 static int
1103 ccw_device_remove (struct device *dev)
1104 {
1105         struct ccw_device *cdev = to_ccwdev(dev);
1106         struct ccw_driver *cdrv = cdev->drv;
1107         int ret;
1108
1109         pr_debug("removing device %s\n", cdev->dev.bus_id);
1110         if (cdrv->remove)
1111                 cdrv->remove(cdev);
1112         if (cdev->online) {
1113                 cdev->online = 0;
1114                 spin_lock_irq(cdev->ccwlock);
1115                 ret = ccw_device_offline(cdev);
1116                 spin_unlock_irq(cdev->ccwlock);
1117                 if (ret == 0)
1118                         wait_event(cdev->private->wait_q,
1119                                    dev_fsm_final_state(cdev));
1120                 else
1121                         //FIXME: we can't fail!
1122                         pr_debug("ccw_device_offline returned %d, device %s\n",
1123                                  ret, cdev->dev.bus_id);
1124         }
1125         ccw_device_set_timeout(cdev, 0);
1126         cdev->drv = 0;
1127         return 0;
1128 }
1129
1130 int
1131 ccw_driver_register (struct ccw_driver *cdriver)
1132 {
1133         struct device_driver *drv = &cdriver->driver;
1134
1135         drv->bus = &ccw_bus_type;
1136         drv->name = cdriver->name;
1137         drv->probe = ccw_device_probe;
1138         drv->remove = ccw_device_remove;
1139
1140         return driver_register(drv);
1141 }
1142
1143 void
1144 ccw_driver_unregister (struct ccw_driver *cdriver)
1145 {
1146         driver_unregister(&cdriver->driver);
1147 }
1148
1149 MODULE_LICENSE("GPL");
1150 EXPORT_SYMBOL(ccw_device_set_online);
1151 EXPORT_SYMBOL(ccw_device_set_offline);
1152 EXPORT_SYMBOL(ccw_driver_register);
1153 EXPORT_SYMBOL(ccw_driver_unregister);
1154 EXPORT_SYMBOL(get_ccwdev_by_busid);
1155 EXPORT_SYMBOL(ccw_bus_type);
1156 EXPORT_SYMBOL(ccw_device_work);
1157 EXPORT_SYMBOL(ccw_device_notify_work);