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Diffstat (limited to 'drivers/s390/cio/device.c')
-rw-r--r--drivers/s390/cio/device.c1135
1 files changed, 1135 insertions, 0 deletions
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c
new file mode 100644
index 000000000000..df0325505e4e
--- /dev/null
+++ b/drivers/s390/cio/device.c
@@ -0,0 +1,1135 @@
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
26#include "cio.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. */
37static int
38ccw_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/*
57 * Hotplugging interface for ccw devices.
58 * Heavily modeled on pci and usb hotplug.
59 */
60static int
61ccw_hotplug (struct device *dev, char **envp, int num_envp,
62 char *buffer, int buffer_size)
63{
64 struct ccw_device *cdev = to_ccwdev(dev);
65 int i = 0;
66 int length = 0;
67
68 if (!cdev)
69 return -ENODEV;
70
71 /* what we want to pass to /sbin/hotplug */
72
73 envp[i++] = buffer;
74 length += scnprintf(buffer, buffer_size - length, "CU_TYPE=%04X",
75 cdev->id.cu_type);
76 if ((buffer_size - length <= 0) || (i >= num_envp))
77 return -ENOMEM;
78 ++length;
79 buffer += length;
80
81 envp[i++] = buffer;
82 length += scnprintf(buffer, buffer_size - length, "CU_MODEL=%02X",
83 cdev->id.cu_model);
84 if ((buffer_size - length <= 0) || (i >= num_envp))
85 return -ENOMEM;
86 ++length;
87 buffer += length;
88
89 /* The next two can be zero, that's ok for us */
90 envp[i++] = buffer;
91 length += scnprintf(buffer, buffer_size - length, "DEV_TYPE=%04X",
92 cdev->id.dev_type);
93 if ((buffer_size - length <= 0) || (i >= num_envp))
94 return -ENOMEM;
95 ++length;
96 buffer += length;
97
98 envp[i++] = buffer;
99 length += scnprintf(buffer, buffer_size - length, "DEV_MODEL=%02X",
100 cdev->id.dev_model);
101 if ((buffer_size - length <= 0) || (i >= num_envp))
102 return -ENOMEM;
103
104 envp[i] = 0;
105
106 return 0;
107}
108
109struct bus_type ccw_bus_type = {
110 .name = "ccw",
111 .match = &ccw_bus_match,
112 .hotplug = &ccw_hotplug,
113};
114
115static int io_subchannel_probe (struct device *);
116static int io_subchannel_remove (struct device *);
117void io_subchannel_irq (struct device *);
118static int io_subchannel_notify(struct device *, int);
119static void io_subchannel_verify(struct device *);
120static void io_subchannel_ioterm(struct device *);
121static void io_subchannel_shutdown(struct device *);
122
123struct css_driver io_subchannel_driver = {
124 .subchannel_type = SUBCHANNEL_TYPE_IO,
125 .drv = {
126 .name = "io_subchannel",
127 .bus = &css_bus_type,
128 .probe = &io_subchannel_probe,
129 .remove = &io_subchannel_remove,
130 .shutdown = &io_subchannel_shutdown,
131 },
132 .irq = io_subchannel_irq,
133 .notify = io_subchannel_notify,
134 .verify = io_subchannel_verify,
135 .termination = io_subchannel_ioterm,
136};
137
138struct workqueue_struct *ccw_device_work;
139struct workqueue_struct *ccw_device_notify_work;
140static wait_queue_head_t ccw_device_init_wq;
141static atomic_t ccw_device_init_count;
142
143static int __init
144init_ccw_bus_type (void)
145{
146 int ret;
147
148 init_waitqueue_head(&ccw_device_init_wq);
149 atomic_set(&ccw_device_init_count, 0);
150
151 ccw_device_work = create_singlethread_workqueue("cio");
152 if (!ccw_device_work)
153 return -ENOMEM; /* FIXME: better errno ? */
154 ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
155 if (!ccw_device_notify_work) {
156 ret = -ENOMEM; /* FIXME: better errno ? */
157 goto out_err;
158 }
159 slow_path_wq = create_singlethread_workqueue("kslowcrw");
160 if (!slow_path_wq) {
161 ret = -ENOMEM; /* FIXME: better errno ? */
162 goto out_err;
163 }
164 if ((ret = bus_register (&ccw_bus_type)))
165 goto out_err;
166
167 if ((ret = driver_register(&io_subchannel_driver.drv)))
168 goto out_err;
169
170 wait_event(ccw_device_init_wq,
171 atomic_read(&ccw_device_init_count) == 0);
172 flush_workqueue(ccw_device_work);
173 return 0;
174out_err:
175 if (ccw_device_work)
176 destroy_workqueue(ccw_device_work);
177 if (ccw_device_notify_work)
178 destroy_workqueue(ccw_device_notify_work);
179 if (slow_path_wq)
180 destroy_workqueue(slow_path_wq);
181 return ret;
182}
183
184static void __exit
185cleanup_ccw_bus_type (void)
186{
187 driver_unregister(&io_subchannel_driver.drv);
188 bus_unregister(&ccw_bus_type);
189 destroy_workqueue(ccw_device_notify_work);
190 destroy_workqueue(ccw_device_work);
191}
192
193subsys_initcall(init_ccw_bus_type);
194module_exit(cleanup_ccw_bus_type);
195
196/************************ device handling **************************/
197
198/*
199 * A ccw_device has some interfaces in sysfs in addition to the
200 * standard ones.
201 * The following entries are designed to export the information which
202 * resided in 2.4 in /proc/subchannels. Subchannel and device number
203 * are obvious, so they don't have an entry :)
204 * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
205 */
206static ssize_t
207chpids_show (struct device * dev, char * buf)
208{
209 struct subchannel *sch = to_subchannel(dev);
210 struct ssd_info *ssd = &sch->ssd_info;
211 ssize_t ret = 0;
212 int chp;
213
214 for (chp = 0; chp < 8; chp++)
215 ret += sprintf (buf+ret, "%02x ", ssd->chpid[chp]);
216
217 ret += sprintf (buf+ret, "\n");
218 return min((ssize_t)PAGE_SIZE, ret);
219}
220
221static ssize_t
222pimpampom_show (struct device * dev, char * buf)
223{
224 struct subchannel *sch = to_subchannel(dev);
225 struct pmcw *pmcw = &sch->schib.pmcw;
226
227 return sprintf (buf, "%02x %02x %02x\n",
228 pmcw->pim, pmcw->pam, pmcw->pom);
229}
230
231static ssize_t
232devtype_show (struct device *dev, char *buf)
233{
234 struct ccw_device *cdev = to_ccwdev(dev);
235 struct ccw_device_id *id = &(cdev->id);
236
237 if (id->dev_type != 0)
238 return sprintf(buf, "%04x/%02x\n",
239 id->dev_type, id->dev_model);
240 else
241 return sprintf(buf, "n/a\n");
242}
243
244static ssize_t
245cutype_show (struct device *dev, char *buf)
246{
247 struct ccw_device *cdev = to_ccwdev(dev);
248 struct ccw_device_id *id = &(cdev->id);
249
250 return sprintf(buf, "%04x/%02x\n",
251 id->cu_type, id->cu_model);
252}
253
254static ssize_t
255online_show (struct device *dev, char *buf)
256{
257 struct ccw_device *cdev = to_ccwdev(dev);
258
259 return sprintf(buf, cdev->online ? "1\n" : "0\n");
260}
261
262static void
263ccw_device_remove_disconnected(struct ccw_device *cdev)
264{
265 struct subchannel *sch;
266 /*
267 * Forced offline in disconnected state means
268 * 'throw away device'.
269 */
270 sch = to_subchannel(cdev->dev.parent);
271 device_unregister(&sch->dev);
272 /* Reset intparm to zeroes. */
273 sch->schib.pmcw.intparm = 0;
274 cio_modify(sch);
275 put_device(&sch->dev);
276}
277
278int
279ccw_device_set_offline(struct ccw_device *cdev)
280{
281 int ret;
282
283 if (!cdev)
284 return -ENODEV;
285 if (!cdev->online || !cdev->drv)
286 return -EINVAL;
287
288 if (cdev->drv->set_offline) {
289 ret = cdev->drv->set_offline(cdev);
290 if (ret != 0)
291 return ret;
292 }
293 cdev->online = 0;
294 spin_lock_irq(cdev->ccwlock);
295 ret = ccw_device_offline(cdev);
296 if (ret == -ENODEV) {
297 if (cdev->private->state != DEV_STATE_NOT_OPER) {
298 cdev->private->state = DEV_STATE_OFFLINE;
299 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
300 }
301 spin_unlock_irq(cdev->ccwlock);
302 return ret;
303 }
304 spin_unlock_irq(cdev->ccwlock);
305 if (ret == 0)
306 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
307 else {
308 pr_debug("ccw_device_offline returned %d, device %s\n",
309 ret, cdev->dev.bus_id);
310 cdev->online = 1;
311 }
312 return ret;
313}
314
315int
316ccw_device_set_online(struct ccw_device *cdev)
317{
318 int ret;
319
320 if (!cdev)
321 return -ENODEV;
322 if (cdev->online || !cdev->drv)
323 return -EINVAL;
324
325 spin_lock_irq(cdev->ccwlock);
326 ret = ccw_device_online(cdev);
327 spin_unlock_irq(cdev->ccwlock);
328 if (ret == 0)
329 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
330 else {
331 pr_debug("ccw_device_online returned %d, device %s\n",
332 ret, cdev->dev.bus_id);
333 return ret;
334 }
335 if (cdev->private->state != DEV_STATE_ONLINE)
336 return -ENODEV;
337 if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
338 cdev->online = 1;
339 return 0;
340 }
341 spin_lock_irq(cdev->ccwlock);
342 ret = ccw_device_offline(cdev);
343 spin_unlock_irq(cdev->ccwlock);
344 if (ret == 0)
345 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
346 else
347 pr_debug("ccw_device_offline returned %d, device %s\n",
348 ret, cdev->dev.bus_id);
349 return (ret = 0) ? -ENODEV : ret;
350}
351
352static ssize_t
353online_store (struct device *dev, const char *buf, size_t count)
354{
355 struct ccw_device *cdev = to_ccwdev(dev);
356 int i, force, ret;
357 char *tmp;
358
359 if (atomic_compare_and_swap(0, 1, &cdev->private->onoff))
360 return -EAGAIN;
361
362 if (cdev->drv && !try_module_get(cdev->drv->owner)) {
363 atomic_set(&cdev->private->onoff, 0);
364 return -EINVAL;
365 }
366 if (!strncmp(buf, "force\n", count)) {
367 force = 1;
368 i = 1;
369 } else {
370 force = 0;
371 i = simple_strtoul(buf, &tmp, 16);
372 }
373 if (i == 1) {
374 /* Do device recognition, if needed. */
375 if (cdev->id.cu_type == 0) {
376 ret = ccw_device_recognition(cdev);
377 if (ret) {
378 printk(KERN_WARNING"Couldn't start recognition "
379 "for device %s (ret=%d)\n",
380 cdev->dev.bus_id, ret);
381 goto out;
382 }
383 wait_event(cdev->private->wait_q,
384 cdev->private->flags.recog_done);
385 }
386 if (cdev->drv && cdev->drv->set_online)
387 ccw_device_set_online(cdev);
388 } else if (i == 0) {
389 if (cdev->private->state == DEV_STATE_DISCONNECTED)
390 ccw_device_remove_disconnected(cdev);
391 else if (cdev->drv && cdev->drv->set_offline)
392 ccw_device_set_offline(cdev);
393 }
394 if (force && cdev->private->state == DEV_STATE_BOXED) {
395 ret = ccw_device_stlck(cdev);
396 if (ret) {
397 printk(KERN_WARNING"ccw_device_stlck for device %s "
398 "returned %d!\n", cdev->dev.bus_id, ret);
399 goto out;
400 }
401 /* Do device recognition, if needed. */
402 if (cdev->id.cu_type == 0) {
403 cdev->private->state = DEV_STATE_NOT_OPER;
404 ret = ccw_device_recognition(cdev);
405 if (ret) {
406 printk(KERN_WARNING"Couldn't start recognition "
407 "for device %s (ret=%d)\n",
408 cdev->dev.bus_id, ret);
409 goto out;
410 }
411 wait_event(cdev->private->wait_q,
412 cdev->private->flags.recog_done);
413 }
414 if (cdev->drv && cdev->drv->set_online)
415 ccw_device_set_online(cdev);
416 }
417 out:
418 if (cdev->drv)
419 module_put(cdev->drv->owner);
420 atomic_set(&cdev->private->onoff, 0);
421 return count;
422}
423
424static ssize_t
425available_show (struct device *dev, char *buf)
426{
427 struct ccw_device *cdev = to_ccwdev(dev);
428 struct subchannel *sch;
429
430 switch (cdev->private->state) {
431 case DEV_STATE_BOXED:
432 return sprintf(buf, "boxed\n");
433 case DEV_STATE_DISCONNECTED:
434 case DEV_STATE_DISCONNECTED_SENSE_ID:
435 case DEV_STATE_NOT_OPER:
436 sch = to_subchannel(dev->parent);
437 if (!sch->lpm)
438 return sprintf(buf, "no path\n");
439 else
440 return sprintf(buf, "no device\n");
441 default:
442 /* All other states considered fine. */
443 return sprintf(buf, "good\n");
444 }
445}
446
447static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
448static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
449static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
450static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
451static DEVICE_ATTR(online, 0644, online_show, online_store);
452extern struct device_attribute dev_attr_cmb_enable;
453static DEVICE_ATTR(availability, 0444, available_show, NULL);
454
455static struct attribute * subch_attrs[] = {
456 &dev_attr_chpids.attr,
457 &dev_attr_pimpampom.attr,
458 NULL,
459};
460
461static struct attribute_group subch_attr_group = {
462 .attrs = subch_attrs,
463};
464
465static inline int
466subchannel_add_files (struct device *dev)
467{
468 return sysfs_create_group(&dev->kobj, &subch_attr_group);
469}
470
471static struct attribute * ccwdev_attrs[] = {
472 &dev_attr_devtype.attr,
473 &dev_attr_cutype.attr,
474 &dev_attr_online.attr,
475 &dev_attr_cmb_enable.attr,
476 &dev_attr_availability.attr,
477 NULL,
478};
479
480static struct attribute_group ccwdev_attr_group = {
481 .attrs = ccwdev_attrs,
482};
483
484static inline int
485device_add_files (struct device *dev)
486{
487 return sysfs_create_group(&dev->kobj, &ccwdev_attr_group);
488}
489
490static inline void
491device_remove_files(struct device *dev)
492{
493 sysfs_remove_group(&dev->kobj, &ccwdev_attr_group);
494}
495
496/* this is a simple abstraction for device_register that sets the
497 * correct bus type and adds the bus specific files */
498int
499ccw_device_register(struct ccw_device *cdev)
500{
501 struct device *dev = &cdev->dev;
502 int ret;
503
504 dev->bus = &ccw_bus_type;
505
506 if ((ret = device_add(dev)))
507 return ret;
508
509 set_bit(1, &cdev->private->registered);
510 if ((ret = device_add_files(dev))) {
511 if (test_and_clear_bit(1, &cdev->private->registered))
512 device_del(dev);
513 }
514 return ret;
515}
516
517static struct ccw_device *
518get_disc_ccwdev_by_devno(unsigned int devno, struct ccw_device *sibling)
519{
520 struct ccw_device *cdev;
521 struct list_head *entry;
522 struct device *dev;
523
524 if (!get_bus(&ccw_bus_type))
525 return NULL;
526 down_read(&ccw_bus_type.subsys.rwsem);
527 cdev = NULL;
528 list_for_each(entry, &ccw_bus_type.devices.list) {
529 dev = get_device(container_of(entry,
530 struct device, bus_list));
531 if (!dev)
532 continue;
533 cdev = to_ccwdev(dev);
534 if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
535 (cdev->private->devno == devno) &&
536 (cdev != sibling)) {
537 cdev->private->state = DEV_STATE_NOT_OPER;
538 break;
539 }
540 put_device(dev);
541 cdev = NULL;
542 }
543 up_read(&ccw_bus_type.subsys.rwsem);
544 put_bus(&ccw_bus_type);
545
546 return cdev;
547}
548
549static void
550ccw_device_add_changed(void *data)
551{
552
553 struct ccw_device *cdev;
554
555 cdev = (struct ccw_device *)data;
556 if (device_add(&cdev->dev)) {
557 put_device(&cdev->dev);
558 return;
559 }
560 set_bit(1, &cdev->private->registered);
561 if (device_add_files(&cdev->dev)) {
562 if (test_and_clear_bit(1, &cdev->private->registered))
563 device_unregister(&cdev->dev);
564 }
565}
566
567extern int css_get_ssd_info(struct subchannel *sch);
568
569void
570ccw_device_do_unreg_rereg(void *data)
571{
572 struct ccw_device *cdev;
573 struct subchannel *sch;
574 int need_rename;
575
576 cdev = (struct ccw_device *)data;
577 sch = to_subchannel(cdev->dev.parent);
578 if (cdev->private->devno != sch->schib.pmcw.dev) {
579 /*
580 * The device number has changed. This is usually only when
581 * a device has been detached under VM and then re-appeared
582 * on another subchannel because of a different attachment
583 * order than before. Ideally, we should should just switch
584 * subchannels, but unfortunately, this is not possible with
585 * the current implementation.
586 * Instead, we search for the old subchannel for this device
587 * number and deregister so there are no collisions with the
588 * newly registered ccw_device.
589 * FIXME: Find another solution so the block layer doesn't
590 * get possibly sick...
591 */
592 struct ccw_device *other_cdev;
593
594 need_rename = 1;
595 other_cdev = get_disc_ccwdev_by_devno(sch->schib.pmcw.dev,
596 cdev);
597 if (other_cdev) {
598 struct subchannel *other_sch;
599
600 other_sch = to_subchannel(other_cdev->dev.parent);
601 if (get_device(&other_sch->dev)) {
602 stsch(other_sch->irq, &other_sch->schib);
603 if (other_sch->schib.pmcw.dnv) {
604 other_sch->schib.pmcw.intparm = 0;
605 cio_modify(other_sch);
606 }
607 device_unregister(&other_sch->dev);
608 }
609 }
610 /* Update ssd info here. */
611 css_get_ssd_info(sch);
612 cdev->private->devno = sch->schib.pmcw.dev;
613 } else
614 need_rename = 0;
615 device_remove_files(&cdev->dev);
616 if (test_and_clear_bit(1, &cdev->private->registered))
617 device_del(&cdev->dev);
618 if (need_rename)
619 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
620 sch->schib.pmcw.dev);
621 PREPARE_WORK(&cdev->private->kick_work,
622 ccw_device_add_changed, (void *)cdev);
623 queue_work(ccw_device_work, &cdev->private->kick_work);
624}
625
626static void
627ccw_device_release(struct device *dev)
628{
629 struct ccw_device *cdev;
630
631 cdev = to_ccwdev(dev);
632 kfree(cdev->private);
633 kfree(cdev);
634}
635
636/*
637 * Register recognized device.
638 */
639static void
640io_subchannel_register(void *data)
641{
642 struct ccw_device *cdev;
643 struct subchannel *sch;
644 int ret;
645 unsigned long flags;
646
647 cdev = (struct ccw_device *) data;
648 sch = to_subchannel(cdev->dev.parent);
649
650 if (!list_empty(&sch->dev.children)) {
651 bus_rescan_devices(&ccw_bus_type);
652 goto out;
653 }
654 /* make it known to the system */
655 ret = ccw_device_register(cdev);
656 if (ret) {
657 printk (KERN_WARNING "%s: could not register %s\n",
658 __func__, cdev->dev.bus_id);
659 put_device(&cdev->dev);
660 spin_lock_irqsave(&sch->lock, flags);
661 sch->dev.driver_data = NULL;
662 spin_unlock_irqrestore(&sch->lock, flags);
663 kfree (cdev->private);
664 kfree (cdev);
665 put_device(&sch->dev);
666 if (atomic_dec_and_test(&ccw_device_init_count))
667 wake_up(&ccw_device_init_wq);
668 return;
669 }
670
671 ret = subchannel_add_files(cdev->dev.parent);
672 if (ret)
673 printk(KERN_WARNING "%s: could not add attributes to %s\n",
674 __func__, sch->dev.bus_id);
675 put_device(&cdev->dev);
676out:
677 cdev->private->flags.recog_done = 1;
678 put_device(&sch->dev);
679 wake_up(&cdev->private->wait_q);
680 if (atomic_dec_and_test(&ccw_device_init_count))
681 wake_up(&ccw_device_init_wq);
682}
683
684void
685ccw_device_call_sch_unregister(void *data)
686{
687 struct ccw_device *cdev = data;
688 struct subchannel *sch;
689
690 sch = to_subchannel(cdev->dev.parent);
691 device_unregister(&sch->dev);
692 /* Reset intparm to zeroes. */
693 sch->schib.pmcw.intparm = 0;
694 cio_modify(sch);
695 put_device(&cdev->dev);
696 put_device(&sch->dev);
697}
698
699/*
700 * subchannel recognition done. Called from the state machine.
701 */
702void
703io_subchannel_recog_done(struct ccw_device *cdev)
704{
705 struct subchannel *sch;
706
707 if (css_init_done == 0) {
708 cdev->private->flags.recog_done = 1;
709 return;
710 }
711 switch (cdev->private->state) {
712 case DEV_STATE_NOT_OPER:
713 cdev->private->flags.recog_done = 1;
714 /* Remove device found not operational. */
715 if (!get_device(&cdev->dev))
716 break;
717 sch = to_subchannel(cdev->dev.parent);
718 PREPARE_WORK(&cdev->private->kick_work,
719 ccw_device_call_sch_unregister, (void *) cdev);
720 queue_work(slow_path_wq, &cdev->private->kick_work);
721 if (atomic_dec_and_test(&ccw_device_init_count))
722 wake_up(&ccw_device_init_wq);
723 break;
724 case DEV_STATE_BOXED:
725 /* Device did not respond in time. */
726 case DEV_STATE_OFFLINE:
727 /*
728 * We can't register the device in interrupt context so
729 * we schedule a work item.
730 */
731 if (!get_device(&cdev->dev))
732 break;
733 PREPARE_WORK(&cdev->private->kick_work,
734 io_subchannel_register, (void *) cdev);
735 queue_work(slow_path_wq, &cdev->private->kick_work);
736 break;
737 }
738}
739
740static int
741io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
742{
743 int rc;
744 struct ccw_device_private *priv;
745
746 sch->dev.driver_data = cdev;
747 sch->driver = &io_subchannel_driver;
748 cdev->ccwlock = &sch->lock;
749 /* Init private data. */
750 priv = cdev->private;
751 priv->devno = sch->schib.pmcw.dev;
752 priv->irq = sch->irq;
753 priv->state = DEV_STATE_NOT_OPER;
754 INIT_LIST_HEAD(&priv->cmb_list);
755 init_waitqueue_head(&priv->wait_q);
756 init_timer(&priv->timer);
757
758 /* Set an initial name for the device. */
759 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.0.%04x",
760 sch->schib.pmcw.dev);
761
762 /* Increase counter of devices currently in recognition. */
763 atomic_inc(&ccw_device_init_count);
764
765 /* Start async. device sensing. */
766 spin_lock_irq(&sch->lock);
767 rc = ccw_device_recognition(cdev);
768 spin_unlock_irq(&sch->lock);
769 if (rc) {
770 if (atomic_dec_and_test(&ccw_device_init_count))
771 wake_up(&ccw_device_init_wq);
772 }
773 return rc;
774}
775
776static int
777io_subchannel_probe (struct device *pdev)
778{
779 struct subchannel *sch;
780 struct ccw_device *cdev;
781 int rc;
782 unsigned long flags;
783
784 sch = to_subchannel(pdev);
785 if (sch->dev.driver_data) {
786 /*
787 * This subchannel already has an associated ccw_device.
788 * Register it and exit. This happens for all early
789 * device, e.g. the console.
790 */
791 cdev = sch->dev.driver_data;
792 device_initialize(&cdev->dev);
793 ccw_device_register(cdev);
794 subchannel_add_files(&sch->dev);
795 /*
796 * Check if the device is already online. If it is
797 * the reference count needs to be corrected
798 * (see ccw_device_online and css_init_done for the
799 * ugly details).
800 */
801 if (cdev->private->state != DEV_STATE_NOT_OPER &&
802 cdev->private->state != DEV_STATE_OFFLINE &&
803 cdev->private->state != DEV_STATE_BOXED)
804 get_device(&cdev->dev);
805 return 0;
806 }
807 cdev = kmalloc (sizeof(*cdev), GFP_KERNEL);
808 if (!cdev)
809 return -ENOMEM;
810 memset(cdev, 0, sizeof(struct ccw_device));
811 cdev->private = kmalloc(sizeof(struct ccw_device_private),
812 GFP_KERNEL | GFP_DMA);
813 if (!cdev->private) {
814 kfree(cdev);
815 return -ENOMEM;
816 }
817 memset(cdev->private, 0, sizeof(struct ccw_device_private));
818 atomic_set(&cdev->private->onoff, 0);
819 cdev->dev = (struct device) {
820 .parent = pdev,
821 .release = ccw_device_release,
822 };
823 INIT_LIST_HEAD(&cdev->private->kick_work.entry);
824 /* Do first half of device_register. */
825 device_initialize(&cdev->dev);
826
827 if (!get_device(&sch->dev)) {
828 if (cdev->dev.release)
829 cdev->dev.release(&cdev->dev);
830 return -ENODEV;
831 }
832
833 rc = io_subchannel_recog(cdev, to_subchannel(pdev));
834 if (rc) {
835 spin_lock_irqsave(&sch->lock, flags);
836 sch->dev.driver_data = NULL;
837 spin_unlock_irqrestore(&sch->lock, flags);
838 if (cdev->dev.release)
839 cdev->dev.release(&cdev->dev);
840 }
841
842 return rc;
843}
844
845static void
846ccw_device_unregister(void *data)
847{
848 struct ccw_device *cdev;
849
850 cdev = (struct ccw_device *)data;
851 if (test_and_clear_bit(1, &cdev->private->registered))
852 device_unregister(&cdev->dev);
853 put_device(&cdev->dev);
854}
855
856static int
857io_subchannel_remove (struct device *dev)
858{
859 struct ccw_device *cdev;
860 unsigned long flags;
861
862 if (!dev->driver_data)
863 return 0;
864 cdev = dev->driver_data;
865 /* Set ccw device to not operational and drop reference. */
866 spin_lock_irqsave(cdev->ccwlock, flags);
867 dev->driver_data = NULL;
868 cdev->private->state = DEV_STATE_NOT_OPER;
869 spin_unlock_irqrestore(cdev->ccwlock, flags);
870 /*
871 * Put unregistration on workqueue to avoid livelocks on the css bus
872 * semaphore.
873 */
874 if (get_device(&cdev->dev)) {
875 PREPARE_WORK(&cdev->private->kick_work,
876 ccw_device_unregister, (void *) cdev);
877 queue_work(ccw_device_work, &cdev->private->kick_work);
878 }
879 return 0;
880}
881
882static int
883io_subchannel_notify(struct device *dev, int event)
884{
885 struct ccw_device *cdev;
886
887 cdev = dev->driver_data;
888 if (!cdev)
889 return 0;
890 if (!cdev->drv)
891 return 0;
892 if (!cdev->online)
893 return 0;
894 return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
895}
896
897static void
898io_subchannel_verify(struct device *dev)
899{
900 struct ccw_device *cdev;
901
902 cdev = dev->driver_data;
903 if (cdev)
904 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
905}
906
907static void
908io_subchannel_ioterm(struct device *dev)
909{
910 struct ccw_device *cdev;
911
912 cdev = dev->driver_data;
913 if (!cdev)
914 return;
915 cdev->private->state = DEV_STATE_CLEAR_VERIFY;
916 if (cdev->handler)
917 cdev->handler(cdev, cdev->private->intparm,
918 ERR_PTR(-EIO));
919}
920
921static void
922io_subchannel_shutdown(struct device *dev)
923{
924 struct subchannel *sch;
925 struct ccw_device *cdev;
926 int ret;
927
928 sch = to_subchannel(dev);
929 cdev = dev->driver_data;
930
931 if (cio_is_console(sch->irq))
932 return;
933 if (!sch->schib.pmcw.ena)
934 /* Nothing to do. */
935 return;
936 ret = cio_disable_subchannel(sch);
937 if (ret != -EBUSY)
938 /* Subchannel is disabled, we're done. */
939 return;
940 cdev->private->state = DEV_STATE_QUIESCE;
941 if (cdev->handler)
942 cdev->handler(cdev, cdev->private->intparm,
943 ERR_PTR(-EIO));
944 ret = ccw_device_cancel_halt_clear(cdev);
945 if (ret == -EBUSY) {
946 ccw_device_set_timeout(cdev, HZ/10);
947 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
948 }
949 cio_disable_subchannel(sch);
950}
951
952#ifdef CONFIG_CCW_CONSOLE
953static struct ccw_device console_cdev;
954static struct ccw_device_private console_private;
955static int console_cdev_in_use;
956
957static int
958ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
959{
960 int rc;
961
962 /* Initialize the ccw_device structure. */
963 cdev->dev = (struct device) {
964 .parent = &sch->dev,
965 };
966 /* Initialize the subchannel structure */
967 sch->dev.parent = &css_bus_device;
968 sch->dev.bus = &css_bus_type;
969
970 rc = io_subchannel_recog(cdev, sch);
971 if (rc)
972 return rc;
973
974 /* Now wait for the async. recognition to come to an end. */
975 spin_lock_irq(cdev->ccwlock);
976 while (!dev_fsm_final_state(cdev))
977 wait_cons_dev();
978 rc = -EIO;
979 if (cdev->private->state != DEV_STATE_OFFLINE)
980 goto out_unlock;
981 ccw_device_online(cdev);
982 while (!dev_fsm_final_state(cdev))
983 wait_cons_dev();
984 if (cdev->private->state != DEV_STATE_ONLINE)
985 goto out_unlock;
986 rc = 0;
987out_unlock:
988 spin_unlock_irq(cdev->ccwlock);
989 return 0;
990}
991
992struct ccw_device *
993ccw_device_probe_console(void)
994{
995 struct subchannel *sch;
996 int ret;
997
998 if (xchg(&console_cdev_in_use, 1) != 0)
999 return NULL;
1000 sch = cio_probe_console();
1001 if (IS_ERR(sch)) {
1002 console_cdev_in_use = 0;
1003 return (void *) sch;
1004 }
1005 memset(&console_cdev, 0, sizeof(struct ccw_device));
1006 memset(&console_private, 0, sizeof(struct ccw_device_private));
1007 console_cdev.private = &console_private;
1008 ret = ccw_device_console_enable(&console_cdev, sch);
1009 if (ret) {
1010 cio_release_console();
1011 console_cdev_in_use = 0;
1012 return ERR_PTR(ret);
1013 }
1014 console_cdev.online = 1;
1015 return &console_cdev;
1016}
1017#endif
1018
1019/*
1020 * get ccw_device matching the busid, but only if owned by cdrv
1021 */
1022struct ccw_device *
1023get_ccwdev_by_busid(struct ccw_driver *cdrv, const char *bus_id)
1024{
1025 struct device *d, *dev;
1026 struct device_driver *drv;
1027
1028 drv = get_driver(&cdrv->driver);
1029 if (!drv)
1030 return 0;
1031
1032 down_read(&drv->bus->subsys.rwsem);
1033
1034 dev = NULL;
1035 list_for_each_entry(d, &drv->devices, driver_list) {
1036 dev = get_device(d);
1037
1038 if (dev && !strncmp(bus_id, dev->bus_id, BUS_ID_SIZE))
1039 break;
1040 else if (dev) {
1041 put_device(dev);
1042 dev = NULL;
1043 }
1044 }
1045 up_read(&drv->bus->subsys.rwsem);
1046 put_driver(drv);
1047
1048 return dev ? to_ccwdev(dev) : 0;
1049}
1050
1051/************************** device driver handling ************************/
1052
1053/* This is the implementation of the ccw_driver class. The probe, remove
1054 * and release methods are initially very similar to the device_driver
1055 * implementations, with the difference that they have ccw_device
1056 * arguments.
1057 *
1058 * A ccw driver also contains the information that is needed for
1059 * device matching.
1060 */
1061static int
1062ccw_device_probe (struct device *dev)
1063{
1064 struct ccw_device *cdev = to_ccwdev(dev);
1065 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1066 int ret;
1067
1068 cdev->drv = cdrv; /* to let the driver call _set_online */
1069
1070 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1071
1072 if (ret) {
1073 cdev->drv = 0;
1074 return ret;
1075 }
1076
1077 return 0;
1078}
1079
1080static int
1081ccw_device_remove (struct device *dev)
1082{
1083 struct ccw_device *cdev = to_ccwdev(dev);
1084 struct ccw_driver *cdrv = cdev->drv;
1085 int ret;
1086
1087 pr_debug("removing device %s\n", cdev->dev.bus_id);
1088 if (cdrv->remove)
1089 cdrv->remove(cdev);
1090 if (cdev->online) {
1091 cdev->online = 0;
1092 spin_lock_irq(cdev->ccwlock);
1093 ret = ccw_device_offline(cdev);
1094 spin_unlock_irq(cdev->ccwlock);
1095 if (ret == 0)
1096 wait_event(cdev->private->wait_q,
1097 dev_fsm_final_state(cdev));
1098 else
1099 //FIXME: we can't fail!
1100 pr_debug("ccw_device_offline returned %d, device %s\n",
1101 ret, cdev->dev.bus_id);
1102 }
1103 ccw_device_set_timeout(cdev, 0);
1104 cdev->drv = 0;
1105 return 0;
1106}
1107
1108int
1109ccw_driver_register (struct ccw_driver *cdriver)
1110{
1111 struct device_driver *drv = &cdriver->driver;
1112
1113 drv->bus = &ccw_bus_type;
1114 drv->name = cdriver->name;
1115 drv->probe = ccw_device_probe;
1116 drv->remove = ccw_device_remove;
1117
1118 return driver_register(drv);
1119}
1120
1121void
1122ccw_driver_unregister (struct ccw_driver *cdriver)
1123{
1124 driver_unregister(&cdriver->driver);
1125}
1126
1127MODULE_LICENSE("GPL");
1128EXPORT_SYMBOL(ccw_device_set_online);
1129EXPORT_SYMBOL(ccw_device_set_offline);
1130EXPORT_SYMBOL(ccw_driver_register);
1131EXPORT_SYMBOL(ccw_driver_unregister);
1132EXPORT_SYMBOL(get_ccwdev_by_busid);
1133EXPORT_SYMBOL(ccw_bus_type);
1134EXPORT_SYMBOL(ccw_device_work);
1135EXPORT_SYMBOL(ccw_device_notify_work);
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-12 13:38:30 -0500