2 * drivers/s390/cio/device.c
3 * bus driver for ccw devices
5 * Copyright IBM Corp. 2002,2008
6 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
7 * Cornelia Huck (cornelia.huck@de.ibm.com)
8 * Martin Schwidefsky (schwidefsky@de.ibm.com)
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/errno.h>
14 #include <linux/err.h>
15 #include <linux/slab.h>
16 #include <linux/list.h>
17 #include <linux/device.h>
18 #include <linux/workqueue.h>
19 #include <linux/timer.h>
21 #include <asm/ccwdev.h>
23 #include <asm/param.h> /* HZ */
29 #include "cio_debug.h"
34 #include "blacklist.h"
36 static struct timer_list recovery_timer;
37 static DEFINE_SPINLOCK(recovery_lock);
38 static int recovery_phase;
39 static const unsigned long recovery_delay[] = { 3, 30, 300 };
41 /******************* bus type handling ***********************/
43 /* The Linux driver model distinguishes between a bus type and
44 * the bus itself. Of course we only have one channel
45 * subsystem driver and one channel system per machine, but
46 * we still use the abstraction. T.R. says it's a good idea. */
48 ccw_bus_match (struct device * dev, struct device_driver * drv)
50 struct ccw_device *cdev = to_ccwdev(dev);
51 struct ccw_driver *cdrv = to_ccwdrv(drv);
52 const struct ccw_device_id *ids = cdrv->ids, *found;
57 found = ccw_device_id_match(ids, &cdev->id);
61 cdev->id.driver_info = found->driver_info;
66 /* Store modalias string delimited by prefix/suffix string into buffer with
67 * specified size. Return length of resulting string (excluding trailing '\0')
68 * even if string doesn't fit buffer (snprintf semantics). */
69 static int snprint_alias(char *buf, size_t size,
70 struct ccw_device_id *id, const char *suffix)
74 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
80 if (id->dev_type != 0)
81 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
82 id->dev_model, suffix);
84 len += snprintf(buf, size, "dtdm%s", suffix);
89 /* Set up environment variables for ccw device uevent. Return 0 on success,
90 * non-zero otherwise. */
91 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
93 struct ccw_device *cdev = to_ccwdev(dev);
94 struct ccw_device_id *id = &(cdev->id);
96 char modalias_buf[30];
99 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
104 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
108 /* The next two can be zero, that's ok for us */
110 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
115 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
120 snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
121 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
125 struct bus_type ccw_bus_type;
127 static void io_subchannel_irq(struct subchannel *);
128 static int io_subchannel_probe(struct subchannel *);
129 static int io_subchannel_remove(struct subchannel *);
130 static void io_subchannel_shutdown(struct subchannel *);
131 static int io_subchannel_sch_event(struct subchannel *, int);
132 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
135 static struct css_device_id io_subchannel_ids[] = {
136 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
137 { /* end of list */ },
139 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
141 static int io_subchannel_prepare(struct subchannel *sch)
143 struct ccw_device *cdev;
145 * Don't allow suspend while a ccw device registration
146 * is still outstanding.
148 cdev = sch_get_cdev(sch);
149 if (cdev && !device_is_registered(&cdev->dev))
154 static struct css_driver io_subchannel_driver = {
155 .owner = THIS_MODULE,
156 .subchannel_type = io_subchannel_ids,
157 .name = "io_subchannel",
158 .irq = io_subchannel_irq,
159 .sch_event = io_subchannel_sch_event,
160 .chp_event = io_subchannel_chp_event,
161 .probe = io_subchannel_probe,
162 .remove = io_subchannel_remove,
163 .shutdown = io_subchannel_shutdown,
164 .prepare = io_subchannel_prepare,
167 struct workqueue_struct *ccw_device_work;
168 wait_queue_head_t ccw_device_init_wq;
169 atomic_t ccw_device_init_count;
171 static void recovery_func(unsigned long data);
174 init_ccw_bus_type (void)
178 init_waitqueue_head(&ccw_device_init_wq);
179 atomic_set(&ccw_device_init_count, 0);
180 setup_timer(&recovery_timer, recovery_func, 0);
182 ccw_device_work = create_singlethread_workqueue("cio");
183 if (!ccw_device_work)
184 return -ENOMEM; /* FIXME: better errno ? */
185 slow_path_wq = create_singlethread_workqueue("kslowcrw");
187 ret = -ENOMEM; /* FIXME: better errno ? */
190 if ((ret = bus_register (&ccw_bus_type)))
193 ret = css_driver_register(&io_subchannel_driver);
197 wait_event(ccw_device_init_wq,
198 atomic_read(&ccw_device_init_count) == 0);
199 flush_workqueue(ccw_device_work);
203 destroy_workqueue(ccw_device_work);
205 destroy_workqueue(slow_path_wq);
210 cleanup_ccw_bus_type (void)
212 css_driver_unregister(&io_subchannel_driver);
213 bus_unregister(&ccw_bus_type);
214 destroy_workqueue(ccw_device_work);
217 subsys_initcall(init_ccw_bus_type);
218 module_exit(cleanup_ccw_bus_type);
220 /************************ device handling **************************/
223 * A ccw_device has some interfaces in sysfs in addition to the
225 * The following entries are designed to export the information which
226 * resided in 2.4 in /proc/subchannels. Subchannel and device number
227 * are obvious, so they don't have an entry :)
228 * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
231 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
233 struct subchannel *sch = to_subchannel(dev);
234 struct chsc_ssd_info *ssd = &sch->ssd_info;
239 for (chp = 0; chp < 8; chp++) {
241 if (ssd->path_mask & mask)
242 ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
244 ret += sprintf(buf + ret, "00 ");
246 ret += sprintf (buf+ret, "\n");
247 return min((ssize_t)PAGE_SIZE, ret);
251 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
253 struct subchannel *sch = to_subchannel(dev);
254 struct pmcw *pmcw = &sch->schib.pmcw;
256 return sprintf (buf, "%02x %02x %02x\n",
257 pmcw->pim, pmcw->pam, pmcw->pom);
261 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
263 struct ccw_device *cdev = to_ccwdev(dev);
264 struct ccw_device_id *id = &(cdev->id);
266 if (id->dev_type != 0)
267 return sprintf(buf, "%04x/%02x\n",
268 id->dev_type, id->dev_model);
270 return sprintf(buf, "n/a\n");
274 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
276 struct ccw_device *cdev = to_ccwdev(dev);
277 struct ccw_device_id *id = &(cdev->id);
279 return sprintf(buf, "%04x/%02x\n",
280 id->cu_type, id->cu_model);
284 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
286 struct ccw_device *cdev = to_ccwdev(dev);
287 struct ccw_device_id *id = &(cdev->id);
290 len = snprint_alias(buf, PAGE_SIZE, id, "\n");
292 return len > PAGE_SIZE ? PAGE_SIZE : len;
296 online_show (struct device *dev, struct device_attribute *attr, char *buf)
298 struct ccw_device *cdev = to_ccwdev(dev);
300 return sprintf(buf, cdev->online ? "1\n" : "0\n");
303 int ccw_device_is_orphan(struct ccw_device *cdev)
305 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
308 static void ccw_device_unregister(struct ccw_device *cdev)
310 if (test_and_clear_bit(1, &cdev->private->registered))
311 device_del(&cdev->dev);
314 static void ccw_device_remove_orphan_cb(struct work_struct *work)
316 struct ccw_device_private *priv;
317 struct ccw_device *cdev;
319 priv = container_of(work, struct ccw_device_private, kick_work);
321 ccw_device_unregister(cdev);
322 put_device(&cdev->dev);
323 /* Release cdev reference for workqueue processing. */
324 put_device(&cdev->dev);
328 ccw_device_remove_disconnected(struct ccw_device *cdev)
333 * Forced offline in disconnected state means
334 * 'throw away device'.
336 if (ccw_device_is_orphan(cdev)) {
338 * Deregister ccw device.
339 * Unfortunately, we cannot do this directly from the
342 /* Get cdev reference for workqueue processing. */
343 if (!get_device(&cdev->dev))
345 spin_lock_irqsave(cdev->ccwlock, flags);
346 cdev->private->state = DEV_STATE_NOT_OPER;
347 spin_unlock_irqrestore(cdev->ccwlock, flags);
348 PREPARE_WORK(&cdev->private->kick_work,
349 ccw_device_remove_orphan_cb);
350 queue_work(slow_path_wq, &cdev->private->kick_work);
352 /* Deregister subchannel, which will kill the ccw device. */
353 ccw_device_schedule_sch_unregister(cdev);
357 * ccw_device_set_offline() - disable a ccw device for I/O
358 * @cdev: target ccw device
360 * This function calls the driver's set_offline() function for @cdev, if
361 * given, and then disables @cdev.
363 * %0 on success and a negative error value on failure.
365 * enabled, ccw device lock not held
367 int ccw_device_set_offline(struct ccw_device *cdev)
373 if (!cdev->online || !cdev->drv)
376 if (cdev->drv->set_offline) {
377 ret = cdev->drv->set_offline(cdev);
382 spin_lock_irq(cdev->ccwlock);
383 /* Wait until a final state or DISCONNECTED is reached */
384 while (!dev_fsm_final_state(cdev) &&
385 cdev->private->state != DEV_STATE_DISCONNECTED) {
386 spin_unlock_irq(cdev->ccwlock);
387 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
388 cdev->private->state == DEV_STATE_DISCONNECTED));
389 spin_lock_irq(cdev->ccwlock);
391 ret = ccw_device_offline(cdev);
394 spin_unlock_irq(cdev->ccwlock);
395 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
396 cdev->private->state == DEV_STATE_DISCONNECTED));
397 /* Give up reference from ccw_device_set_online(). */
398 put_device(&cdev->dev);
402 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device 0.%x.%04x\n",
403 ret, cdev->private->dev_id.ssid,
404 cdev->private->dev_id.devno);
405 cdev->private->state = DEV_STATE_OFFLINE;
406 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
407 spin_unlock_irq(cdev->ccwlock);
408 /* Give up reference from ccw_device_set_online(). */
409 put_device(&cdev->dev);
414 * ccw_device_set_online() - enable a ccw device for I/O
415 * @cdev: target ccw device
417 * This function first enables @cdev and then calls the driver's set_online()
418 * function for @cdev, if given. If set_online() returns an error, @cdev is
421 * %0 on success and a negative error value on failure.
423 * enabled, ccw device lock not held
425 int ccw_device_set_online(struct ccw_device *cdev)
432 if (cdev->online || !cdev->drv)
434 /* Hold on to an extra reference while device is online. */
435 if (!get_device(&cdev->dev))
438 spin_lock_irq(cdev->ccwlock);
439 ret = ccw_device_online(cdev);
440 spin_unlock_irq(cdev->ccwlock);
442 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
444 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
445 "device 0.%x.%04x\n",
446 ret, cdev->private->dev_id.ssid,
447 cdev->private->dev_id.devno);
448 /* Give up online reference since onlining failed. */
449 put_device(&cdev->dev);
452 spin_lock_irq(cdev->ccwlock);
453 /* Check if online processing was successful */
454 if ((cdev->private->state != DEV_STATE_ONLINE) &&
455 (cdev->private->state != DEV_STATE_W4SENSE)) {
456 spin_unlock_irq(cdev->ccwlock);
457 /* Give up online reference since onlining failed. */
458 put_device(&cdev->dev);
461 spin_unlock_irq(cdev->ccwlock);
462 if (cdev->drv->set_online)
463 ret = cdev->drv->set_online(cdev);
470 spin_lock_irq(cdev->ccwlock);
471 /* Wait until a final state or DISCONNECTED is reached */
472 while (!dev_fsm_final_state(cdev) &&
473 cdev->private->state != DEV_STATE_DISCONNECTED) {
474 spin_unlock_irq(cdev->ccwlock);
475 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
476 cdev->private->state == DEV_STATE_DISCONNECTED));
477 spin_lock_irq(cdev->ccwlock);
479 ret2 = ccw_device_offline(cdev);
482 spin_unlock_irq(cdev->ccwlock);
483 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
484 cdev->private->state == DEV_STATE_DISCONNECTED));
485 /* Give up online reference since onlining failed. */
486 put_device(&cdev->dev);
490 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
491 "device 0.%x.%04x\n",
492 ret2, cdev->private->dev_id.ssid,
493 cdev->private->dev_id.devno);
494 cdev->private->state = DEV_STATE_OFFLINE;
495 spin_unlock_irq(cdev->ccwlock);
496 /* Give up online reference since onlining failed. */
497 put_device(&cdev->dev);
501 static int online_store_handle_offline(struct ccw_device *cdev)
503 if (cdev->private->state == DEV_STATE_DISCONNECTED)
504 ccw_device_remove_disconnected(cdev);
505 else if (cdev->online && cdev->drv && cdev->drv->set_offline)
506 return ccw_device_set_offline(cdev);
510 static int online_store_recog_and_online(struct ccw_device *cdev)
514 /* Do device recognition, if needed. */
515 if (cdev->private->state == DEV_STATE_BOXED) {
516 ret = ccw_device_recognition(cdev);
518 CIO_MSG_EVENT(0, "Couldn't start recognition "
519 "for device 0.%x.%04x (ret=%d)\n",
520 cdev->private->dev_id.ssid,
521 cdev->private->dev_id.devno, ret);
524 wait_event(cdev->private->wait_q,
525 cdev->private->flags.recog_done);
526 if (cdev->private->state != DEV_STATE_OFFLINE)
527 /* recognition failed */
530 if (cdev->drv && cdev->drv->set_online)
531 ccw_device_set_online(cdev);
535 static int online_store_handle_online(struct ccw_device *cdev, int force)
539 ret = online_store_recog_and_online(cdev);
542 if (force && cdev->private->state == DEV_STATE_BOXED) {
543 ret = ccw_device_stlck(cdev);
546 if (cdev->id.cu_type == 0)
547 cdev->private->state = DEV_STATE_NOT_OPER;
548 ret = online_store_recog_and_online(cdev);
555 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
556 const char *buf, size_t count)
558 struct ccw_device *cdev = to_ccwdev(dev);
562 if ((cdev->private->state != DEV_STATE_OFFLINE &&
563 cdev->private->state != DEV_STATE_ONLINE &&
564 cdev->private->state != DEV_STATE_BOXED &&
565 cdev->private->state != DEV_STATE_DISCONNECTED) ||
566 atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
569 if (cdev->drv && !try_module_get(cdev->drv->owner)) {
570 atomic_set(&cdev->private->onoff, 0);
573 if (!strncmp(buf, "force\n", count)) {
579 ret = strict_strtoul(buf, 16, &i);
585 ret = online_store_handle_offline(cdev);
588 ret = online_store_handle_online(cdev, force);
595 module_put(cdev->drv->owner);
596 atomic_set(&cdev->private->onoff, 0);
597 return (ret < 0) ? ret : count;
601 available_show (struct device *dev, struct device_attribute *attr, char *buf)
603 struct ccw_device *cdev = to_ccwdev(dev);
604 struct subchannel *sch;
606 if (ccw_device_is_orphan(cdev))
607 return sprintf(buf, "no device\n");
608 switch (cdev->private->state) {
609 case DEV_STATE_BOXED:
610 return sprintf(buf, "boxed\n");
611 case DEV_STATE_DISCONNECTED:
612 case DEV_STATE_DISCONNECTED_SENSE_ID:
613 case DEV_STATE_NOT_OPER:
614 sch = to_subchannel(dev->parent);
616 return sprintf(buf, "no path\n");
618 return sprintf(buf, "no device\n");
620 /* All other states considered fine. */
621 return sprintf(buf, "good\n");
625 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
626 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
627 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
628 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
629 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
630 static DEVICE_ATTR(online, 0644, online_show, online_store);
631 static DEVICE_ATTR(availability, 0444, available_show, NULL);
633 static struct attribute *io_subchannel_attrs[] = {
634 &dev_attr_chpids.attr,
635 &dev_attr_pimpampom.attr,
639 static struct attribute_group io_subchannel_attr_group = {
640 .attrs = io_subchannel_attrs,
643 static struct attribute * ccwdev_attrs[] = {
644 &dev_attr_devtype.attr,
645 &dev_attr_cutype.attr,
646 &dev_attr_modalias.attr,
647 &dev_attr_online.attr,
648 &dev_attr_cmb_enable.attr,
649 &dev_attr_availability.attr,
653 static struct attribute_group ccwdev_attr_group = {
654 .attrs = ccwdev_attrs,
657 static struct attribute_group *ccwdev_attr_groups[] = {
662 /* this is a simple abstraction for device_register that sets the
663 * correct bus type and adds the bus specific files */
664 static int ccw_device_register(struct ccw_device *cdev)
666 struct device *dev = &cdev->dev;
669 dev->bus = &ccw_bus_type;
671 if ((ret = device_add(dev)))
674 set_bit(1, &cdev->private->registered);
679 struct ccw_dev_id dev_id;
680 struct ccw_device * sibling;
684 match_devno(struct device * dev, void * data)
686 struct match_data * d = data;
687 struct ccw_device * cdev;
689 cdev = to_ccwdev(dev);
690 if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
691 !ccw_device_is_orphan(cdev) &&
692 ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
693 (cdev != d->sibling))
698 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
699 struct ccw_device *sibling)
702 struct match_data data;
704 data.dev_id = *dev_id;
705 data.sibling = sibling;
706 dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
708 return dev ? to_ccwdev(dev) : NULL;
711 static int match_orphan(struct device *dev, void *data)
713 struct ccw_dev_id *dev_id;
714 struct ccw_device *cdev;
717 cdev = to_ccwdev(dev);
718 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
721 static struct ccw_device *
722 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
723 struct ccw_dev_id *dev_id)
727 dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
730 return dev ? to_ccwdev(dev) : NULL;
733 void ccw_device_do_unbind_bind(struct work_struct *work)
735 struct ccw_device_private *priv;
736 struct ccw_device *cdev;
737 struct subchannel *sch;
740 priv = container_of(work, struct ccw_device_private, kick_work);
742 sch = to_subchannel(cdev->dev.parent);
744 if (test_bit(1, &cdev->private->registered)) {
745 device_release_driver(&cdev->dev);
746 ret = device_attach(&cdev->dev);
747 WARN_ON(ret == -ENODEV);
752 ccw_device_release(struct device *dev)
754 struct ccw_device *cdev;
756 cdev = to_ccwdev(dev);
757 /* Release reference of parent subchannel. */
758 put_device(cdev->dev.parent);
759 kfree(cdev->private);
763 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
765 struct ccw_device *cdev;
767 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
769 cdev->private = kzalloc(sizeof(struct ccw_device_private),
770 GFP_KERNEL | GFP_DMA);
775 return ERR_PTR(-ENOMEM);
778 static int io_subchannel_initialize_dev(struct subchannel *sch,
779 struct ccw_device *cdev)
781 cdev->private->cdev = cdev;
782 atomic_set(&cdev->private->onoff, 0);
783 cdev->dev.parent = &sch->dev;
784 cdev->dev.release = ccw_device_release;
785 INIT_WORK(&cdev->private->kick_work, NULL);
786 cdev->dev.groups = ccwdev_attr_groups;
787 /* Do first half of device_register. */
788 device_initialize(&cdev->dev);
789 if (!get_device(&sch->dev)) {
790 /* Release reference from device_initialize(). */
791 put_device(&cdev->dev);
797 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
799 struct ccw_device *cdev;
802 cdev = io_subchannel_allocate_dev(sch);
804 ret = io_subchannel_initialize_dev(sch, cdev);
811 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
813 static void sch_attach_device(struct subchannel *sch,
814 struct ccw_device *cdev)
816 css_update_ssd_info(sch);
817 spin_lock_irq(sch->lock);
818 sch_set_cdev(sch, cdev);
819 cdev->private->schid = sch->schid;
820 cdev->ccwlock = sch->lock;
821 ccw_device_trigger_reprobe(cdev);
822 spin_unlock_irq(sch->lock);
825 static void sch_attach_disconnected_device(struct subchannel *sch,
826 struct ccw_device *cdev)
828 struct subchannel *other_sch;
831 /* Get reference for new parent. */
832 if (!get_device(&sch->dev))
834 other_sch = to_subchannel(cdev->dev.parent);
835 /* Note: device_move() changes cdev->dev.parent */
836 ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
838 CIO_MSG_EVENT(0, "Moving disconnected device 0.%x.%04x failed "
839 "(ret=%d)!\n", cdev->private->dev_id.ssid,
840 cdev->private->dev_id.devno, ret);
841 /* Put reference for new parent. */
842 put_device(&sch->dev);
845 sch_set_cdev(other_sch, NULL);
846 /* No need to keep a subchannel without ccw device around. */
847 css_sch_device_unregister(other_sch);
848 sch_attach_device(sch, cdev);
849 /* Put reference for old parent. */
850 put_device(&other_sch->dev);
853 static void sch_attach_orphaned_device(struct subchannel *sch,
854 struct ccw_device *cdev)
857 struct subchannel *pseudo_sch;
859 /* Get reference for new parent. */
860 if (!get_device(&sch->dev))
862 pseudo_sch = to_subchannel(cdev->dev.parent);
864 * Try to move the ccw device to its new subchannel.
865 * Note: device_move() changes cdev->dev.parent
867 ret = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
869 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
870 "failed (ret=%d)!\n",
871 cdev->private->dev_id.ssid,
872 cdev->private->dev_id.devno, ret);
873 /* Put reference for new parent. */
874 put_device(&sch->dev);
877 sch_attach_device(sch, cdev);
878 /* Put reference on pseudo subchannel. */
879 put_device(&pseudo_sch->dev);
882 static void sch_create_and_recog_new_device(struct subchannel *sch)
884 struct ccw_device *cdev;
886 /* Need to allocate a new ccw device. */
887 cdev = io_subchannel_create_ccwdev(sch);
889 /* OK, we did everything we could... */
890 css_sch_device_unregister(sch);
893 spin_lock_irq(sch->lock);
894 sch_set_cdev(sch, cdev);
895 spin_unlock_irq(sch->lock);
896 /* Start recognition for the new ccw device. */
897 if (io_subchannel_recog(cdev, sch)) {
898 spin_lock_irq(sch->lock);
899 sch_set_cdev(sch, NULL);
900 spin_unlock_irq(sch->lock);
901 css_sch_device_unregister(sch);
902 /* Put reference from io_subchannel_create_ccwdev(). */
903 put_device(&sch->dev);
904 /* Give up initial reference. */
905 put_device(&cdev->dev);
910 void ccw_device_move_to_orphanage(struct work_struct *work)
912 struct ccw_device_private *priv;
913 struct ccw_device *cdev;
914 struct ccw_device *replacing_cdev;
915 struct subchannel *sch;
917 struct channel_subsystem *css;
918 struct ccw_dev_id dev_id;
920 priv = container_of(work, struct ccw_device_private, kick_work);
922 sch = to_subchannel(cdev->dev.parent);
923 css = to_css(sch->dev.parent);
924 dev_id.devno = sch->schib.pmcw.dev;
925 dev_id.ssid = sch->schid.ssid;
927 /* Increase refcount for pseudo subchannel. */
928 get_device(&css->pseudo_subchannel->dev);
930 * Move the orphaned ccw device to the orphanage so the replacing
931 * ccw device can take its place on the subchannel.
932 * Note: device_move() changes cdev->dev.parent
934 ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev,
937 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
938 "(ret=%d)!\n", cdev->private->dev_id.ssid,
939 cdev->private->dev_id.devno, ret);
940 /* Decrease refcount for pseudo subchannel again. */
941 put_device(&css->pseudo_subchannel->dev);
944 cdev->ccwlock = css->pseudo_subchannel->lock;
946 * Search for the replacing ccw device
947 * - among the disconnected devices
950 replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
951 if (replacing_cdev) {
952 sch_attach_disconnected_device(sch, replacing_cdev);
953 /* Release reference from get_disc_ccwdev_by_dev_id() */
954 put_device(&replacing_cdev->dev);
955 /* Release reference of subchannel from old cdev. */
956 put_device(&sch->dev);
959 replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
960 if (replacing_cdev) {
961 sch_attach_orphaned_device(sch, replacing_cdev);
962 /* Release reference from get_orphaned_ccwdev_by_dev_id() */
963 put_device(&replacing_cdev->dev);
964 /* Release reference of subchannel from old cdev. */
965 put_device(&sch->dev);
968 sch_create_and_recog_new_device(sch);
969 /* Release reference of subchannel from old cdev. */
970 put_device(&sch->dev);
974 * Register recognized device.
977 io_subchannel_register(struct work_struct *work)
979 struct ccw_device_private *priv;
980 struct ccw_device *cdev;
981 struct subchannel *sch;
985 priv = container_of(work, struct ccw_device_private, kick_work);
987 sch = to_subchannel(cdev->dev.parent);
989 * Check if subchannel is still registered. It may have become
990 * unregistered if a machine check hit us after finishing
991 * device recognition but before the register work could be
994 if (!device_is_registered(&sch->dev))
996 css_update_ssd_info(sch);
998 * io_subchannel_register() will also be called after device
999 * recognition has been done for a boxed device (which will already
1000 * be registered). We need to reprobe since we may now have sense id
1003 if (device_is_registered(&cdev->dev)) {
1005 ret = device_reprobe(&cdev->dev);
1007 /* We can't do much here. */
1008 CIO_MSG_EVENT(0, "device_reprobe() returned"
1009 " %d for 0.%x.%04x\n", ret,
1010 cdev->private->dev_id.ssid,
1011 cdev->private->dev_id.devno);
1016 * Now we know this subchannel will stay, we can throw
1017 * our delayed uevent.
1019 dev_set_uevent_suppress(&sch->dev, 0);
1020 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1021 /* make it known to the system */
1022 ret = ccw_device_register(cdev);
1024 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
1025 cdev->private->dev_id.ssid,
1026 cdev->private->dev_id.devno, ret);
1027 spin_lock_irqsave(sch->lock, flags);
1028 sch_set_cdev(sch, NULL);
1029 spin_unlock_irqrestore(sch->lock, flags);
1030 /* Release initial device reference. */
1031 put_device(&cdev->dev);
1035 cdev->private->flags.recog_done = 1;
1036 wake_up(&cdev->private->wait_q);
1038 /* Release reference for workqueue processing. */
1039 put_device(&cdev->dev);
1040 if (atomic_dec_and_test(&ccw_device_init_count))
1041 wake_up(&ccw_device_init_wq);
1044 static void ccw_device_call_sch_unregister(struct work_struct *work)
1046 struct ccw_device_private *priv;
1047 struct ccw_device *cdev;
1048 struct subchannel *sch;
1050 priv = container_of(work, struct ccw_device_private, kick_work);
1052 /* Get subchannel reference for local processing. */
1053 if (!get_device(cdev->dev.parent))
1055 sch = to_subchannel(cdev->dev.parent);
1056 css_sch_device_unregister(sch);
1057 /* Release cdev reference for workqueue processing.*/
1058 put_device(&cdev->dev);
1059 /* Release subchannel reference for local processing. */
1060 put_device(&sch->dev);
1063 void ccw_device_schedule_sch_unregister(struct ccw_device *cdev)
1065 /* Get cdev reference for workqueue processing. */
1066 if (!get_device(&cdev->dev))
1068 PREPARE_WORK(&cdev->private->kick_work,
1069 ccw_device_call_sch_unregister);
1070 queue_work(slow_path_wq, &cdev->private->kick_work);
1074 * subchannel recognition done. Called from the state machine.
1077 io_subchannel_recog_done(struct ccw_device *cdev)
1079 if (css_init_done == 0) {
1080 cdev->private->flags.recog_done = 1;
1083 switch (cdev->private->state) {
1084 case DEV_STATE_BOXED:
1085 /* Device did not respond in time. */
1086 case DEV_STATE_NOT_OPER:
1087 cdev->private->flags.recog_done = 1;
1088 ccw_device_schedule_sch_unregister(cdev);
1089 if (atomic_dec_and_test(&ccw_device_init_count))
1090 wake_up(&ccw_device_init_wq);
1092 case DEV_STATE_OFFLINE:
1094 * We can't register the device in interrupt context so
1095 * we schedule a work item.
1097 if (!get_device(&cdev->dev))
1099 PREPARE_WORK(&cdev->private->kick_work,
1100 io_subchannel_register);
1101 queue_work(slow_path_wq, &cdev->private->kick_work);
1107 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1110 struct ccw_device_private *priv;
1112 sch_set_cdev(sch, cdev);
1113 cdev->ccwlock = sch->lock;
1115 /* Init private data. */
1116 priv = cdev->private;
1117 priv->dev_id.devno = sch->schib.pmcw.dev;
1118 priv->dev_id.ssid = sch->schid.ssid;
1119 priv->schid = sch->schid;
1120 priv->state = DEV_STATE_NOT_OPER;
1121 INIT_LIST_HEAD(&priv->cmb_list);
1122 init_waitqueue_head(&priv->wait_q);
1123 init_timer(&priv->timer);
1125 /* Set an initial name for the device. */
1126 if (cio_is_console(sch->schid))
1127 cdev->dev.init_name = cio_get_console_cdev_name(sch);
1129 dev_set_name(&cdev->dev, "0.%x.%04x",
1130 sch->schid.ssid, sch->schib.pmcw.dev);
1132 /* Increase counter of devices currently in recognition. */
1133 atomic_inc(&ccw_device_init_count);
1135 /* Start async. device sensing. */
1136 spin_lock_irq(sch->lock);
1137 rc = ccw_device_recognition(cdev);
1138 spin_unlock_irq(sch->lock);
1140 if (atomic_dec_and_test(&ccw_device_init_count))
1141 wake_up(&ccw_device_init_wq);
1146 static void ccw_device_move_to_sch(struct work_struct *work)
1148 struct ccw_device_private *priv;
1150 struct subchannel *sch;
1151 struct ccw_device *cdev;
1152 struct subchannel *former_parent;
1154 priv = container_of(work, struct ccw_device_private, kick_work);
1157 former_parent = to_subchannel(cdev->dev.parent);
1158 /* Get reference for new parent. */
1159 if (!get_device(&sch->dev))
1161 mutex_lock(&sch->reg_mutex);
1163 * Try to move the ccw device to its new subchannel.
1164 * Note: device_move() changes cdev->dev.parent
1166 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
1167 mutex_unlock(&sch->reg_mutex);
1169 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to subchannel "
1170 "0.%x.%04x failed (ret=%d)!\n",
1171 cdev->private->dev_id.ssid,
1172 cdev->private->dev_id.devno, sch->schid.ssid,
1173 sch->schid.sch_no, rc);
1174 css_sch_device_unregister(sch);
1175 /* Put reference for new parent again. */
1176 put_device(&sch->dev);
1179 if (!sch_is_pseudo_sch(former_parent)) {
1180 spin_lock_irq(former_parent->lock);
1181 sch_set_cdev(former_parent, NULL);
1182 spin_unlock_irq(former_parent->lock);
1183 css_sch_device_unregister(former_parent);
1184 /* Reset intparm to zeroes. */
1185 former_parent->config.intparm = 0;
1186 cio_commit_config(former_parent);
1188 sch_attach_device(sch, cdev);
1190 /* Put reference for old parent. */
1191 put_device(&former_parent->dev);
1192 put_device(&cdev->dev);
1195 static void io_subchannel_irq(struct subchannel *sch)
1197 struct ccw_device *cdev;
1199 cdev = sch_get_cdev(sch);
1201 CIO_TRACE_EVENT(6, "IRQ");
1202 CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1204 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1207 void io_subchannel_init_config(struct subchannel *sch)
1209 memset(&sch->config, 0, sizeof(sch->config));
1210 sch->config.csense = 1;
1211 /* Use subchannel mp mode when there is more than 1 installed CHPID. */
1212 if ((sch->schib.pmcw.pim & (sch->schib.pmcw.pim - 1)) != 0)
1216 static void io_subchannel_init_fields(struct subchannel *sch)
1218 if (cio_is_console(sch->schid))
1221 sch->opm = chp_get_sch_opm(sch);
1222 sch->lpm = sch->schib.pmcw.pam & sch->opm;
1223 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1225 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1226 " - PIM = %02X, PAM = %02X, POM = %02X\n",
1227 sch->schib.pmcw.dev, sch->schid.ssid,
1228 sch->schid.sch_no, sch->schib.pmcw.pim,
1229 sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1231 io_subchannel_init_config(sch);
1234 static void io_subchannel_do_unreg(struct work_struct *work)
1236 struct subchannel *sch;
1238 sch = container_of(work, struct subchannel, work);
1239 css_sch_device_unregister(sch);
1240 put_device(&sch->dev);
1243 /* Schedule unregister if we have no cdev. */
1244 static void io_subchannel_schedule_removal(struct subchannel *sch)
1246 get_device(&sch->dev);
1247 INIT_WORK(&sch->work, io_subchannel_do_unreg);
1248 queue_work(slow_path_wq, &sch->work);
1252 * Note: We always return 0 so that we bind to the device even on error.
1253 * This is needed so that our remove function is called on unregister.
1255 static int io_subchannel_probe(struct subchannel *sch)
1257 struct ccw_device *cdev;
1259 unsigned long flags;
1260 struct ccw_dev_id dev_id;
1262 cdev = sch_get_cdev(sch);
1264 rc = sysfs_create_group(&sch->dev.kobj,
1265 &io_subchannel_attr_group);
1267 CIO_MSG_EVENT(0, "Failed to create io subchannel "
1268 "attributes for subchannel "
1269 "0.%x.%04x (rc=%d)\n",
1270 sch->schid.ssid, sch->schid.sch_no, rc);
1272 * This subchannel already has an associated ccw_device.
1273 * Throw the delayed uevent for the subchannel, register
1274 * the ccw_device and exit. This happens for all early
1275 * devices, e.g. the console.
1277 dev_set_uevent_suppress(&sch->dev, 0);
1278 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1279 cdev->dev.groups = ccwdev_attr_groups;
1280 device_initialize(&cdev->dev);
1281 ccw_device_register(cdev);
1283 * Check if the device is already online. If it is
1284 * the reference count needs to be corrected since we
1285 * didn't obtain a reference in ccw_device_set_online.
1287 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1288 cdev->private->state != DEV_STATE_OFFLINE &&
1289 cdev->private->state != DEV_STATE_BOXED)
1290 get_device(&cdev->dev);
1293 io_subchannel_init_fields(sch);
1294 rc = cio_commit_config(sch);
1297 rc = sysfs_create_group(&sch->dev.kobj,
1298 &io_subchannel_attr_group);
1301 /* Allocate I/O subchannel private data. */
1302 sch->private = kzalloc(sizeof(struct io_subchannel_private),
1303 GFP_KERNEL | GFP_DMA);
1307 * First check if a fitting device may be found amongst the
1308 * disconnected devices or in the orphanage.
1310 dev_id.devno = sch->schib.pmcw.dev;
1311 dev_id.ssid = sch->schid.ssid;
1312 cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1314 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1318 * Schedule moving the device until when we have a registered
1319 * subchannel to move to and succeed the probe. We can
1320 * unregister later again, when the probe is through.
1322 cdev->private->sch = sch;
1323 PREPARE_WORK(&cdev->private->kick_work,
1324 ccw_device_move_to_sch);
1325 queue_work(slow_path_wq, &cdev->private->kick_work);
1328 cdev = io_subchannel_create_ccwdev(sch);
1331 rc = io_subchannel_recog(cdev, sch);
1333 spin_lock_irqsave(sch->lock, flags);
1334 io_subchannel_recog_done(cdev);
1335 spin_unlock_irqrestore(sch->lock, flags);
1339 kfree(sch->private);
1340 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1342 io_subchannel_schedule_removal(sch);
1347 io_subchannel_remove (struct subchannel *sch)
1349 struct ccw_device *cdev;
1350 unsigned long flags;
1352 cdev = sch_get_cdev(sch);
1355 /* Set ccw device to not operational and drop reference. */
1356 spin_lock_irqsave(cdev->ccwlock, flags);
1357 sch_set_cdev(sch, NULL);
1358 cdev->private->state = DEV_STATE_NOT_OPER;
1359 spin_unlock_irqrestore(cdev->ccwlock, flags);
1360 ccw_device_unregister(cdev);
1361 put_device(&cdev->dev);
1362 kfree(sch->private);
1363 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1367 static int io_subchannel_notify(struct subchannel *sch, int event)
1369 struct ccw_device *cdev;
1371 cdev = sch_get_cdev(sch);
1374 return ccw_device_notify(cdev, event);
1377 static void io_subchannel_verify(struct subchannel *sch)
1379 struct ccw_device *cdev;
1381 cdev = sch_get_cdev(sch);
1383 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1386 static int check_for_io_on_path(struct subchannel *sch, int mask)
1388 if (cio_update_schib(sch))
1390 if (scsw_actl(&sch->schib.scsw) && sch->schib.pmcw.lpum == mask)
1395 static void terminate_internal_io(struct subchannel *sch,
1396 struct ccw_device *cdev)
1398 if (cio_clear(sch)) {
1399 /* Recheck device in case clear failed. */
1402 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1404 css_schedule_eval(sch->schid);
1407 cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1408 /* Request retry of internal operation. */
1409 cdev->private->flags.intretry = 1;
1412 cdev->handler(cdev, cdev->private->intparm,
1416 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1418 struct ccw_device *cdev;
1420 cdev = sch_get_cdev(sch);
1423 if (check_for_io_on_path(sch, mask)) {
1424 if (cdev->private->state == DEV_STATE_ONLINE)
1425 ccw_device_kill_io(cdev);
1427 terminate_internal_io(sch, cdev);
1428 /* Re-start path verification. */
1429 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1432 /* trigger path verification. */
1433 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1437 static int io_subchannel_chp_event(struct subchannel *sch,
1438 struct chp_link *link, int event)
1442 mask = chp_ssd_get_mask(&sch->ssd_info, link);
1449 io_subchannel_terminate_path(sch, mask);
1454 io_subchannel_verify(sch);
1457 if (cio_update_schib(sch))
1459 io_subchannel_terminate_path(sch, mask);
1462 if (cio_update_schib(sch))
1464 sch->lpm |= mask & sch->opm;
1465 io_subchannel_verify(sch);
1472 io_subchannel_shutdown(struct subchannel *sch)
1474 struct ccw_device *cdev;
1477 cdev = sch_get_cdev(sch);
1479 if (cio_is_console(sch->schid))
1481 if (!sch->schib.pmcw.ena)
1482 /* Nothing to do. */
1484 ret = cio_disable_subchannel(sch);
1486 /* Subchannel is disabled, we're done. */
1488 cdev->private->state = DEV_STATE_QUIESCE;
1490 cdev->handler(cdev, cdev->private->intparm,
1492 ret = ccw_device_cancel_halt_clear(cdev);
1493 if (ret == -EBUSY) {
1494 ccw_device_set_timeout(cdev, HZ/10);
1495 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1497 cio_disable_subchannel(sch);
1500 static int io_subchannel_get_status(struct subchannel *sch)
1504 if (stsch(sch->schid, &schib) || !schib.pmcw.dnv)
1506 if (sch->schib.pmcw.dnv && (schib.pmcw.dev != sch->schib.pmcw.dev))
1507 return CIO_REVALIDATE;
1513 static int device_is_disconnected(struct ccw_device *cdev)
1517 return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1518 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1521 static int recovery_check(struct device *dev, void *data)
1523 struct ccw_device *cdev = to_ccwdev(dev);
1526 spin_lock_irq(cdev->ccwlock);
1527 switch (cdev->private->state) {
1528 case DEV_STATE_DISCONNECTED:
1529 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1530 cdev->private->dev_id.ssid,
1531 cdev->private->dev_id.devno);
1532 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1535 case DEV_STATE_DISCONNECTED_SENSE_ID:
1539 spin_unlock_irq(cdev->ccwlock);
1544 static void recovery_work_func(struct work_struct *unused)
1548 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1550 spin_lock_irq(&recovery_lock);
1551 if (!timer_pending(&recovery_timer)) {
1552 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1554 mod_timer(&recovery_timer, jiffies +
1555 recovery_delay[recovery_phase] * HZ);
1557 spin_unlock_irq(&recovery_lock);
1559 CIO_MSG_EVENT(4, "recovery: end\n");
1562 static DECLARE_WORK(recovery_work, recovery_work_func);
1564 static void recovery_func(unsigned long data)
1567 * We can't do our recovery in softirq context and it's not
1568 * performance critical, so we schedule it.
1570 schedule_work(&recovery_work);
1573 static void ccw_device_schedule_recovery(void)
1575 unsigned long flags;
1577 CIO_MSG_EVENT(4, "recovery: schedule\n");
1578 spin_lock_irqsave(&recovery_lock, flags);
1579 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1581 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1583 spin_unlock_irqrestore(&recovery_lock, flags);
1586 static int purge_fn(struct device *dev, void *data)
1588 struct ccw_device *cdev = to_ccwdev(dev);
1589 struct ccw_device_private *priv = cdev->private;
1592 spin_lock_irq(cdev->ccwlock);
1593 unreg = is_blacklisted(priv->dev_id.ssid, priv->dev_id.devno) &&
1594 (priv->state == DEV_STATE_OFFLINE);
1595 spin_unlock_irq(cdev->ccwlock);
1598 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", priv->dev_id.ssid,
1599 priv->dev_id.devno);
1600 ccw_device_schedule_sch_unregister(cdev);
1603 /* Abort loop in case of pending signal. */
1604 if (signal_pending(current))
1611 * ccw_purge_blacklisted - purge unused, blacklisted devices
1613 * Unregister all ccw devices that are offline and on the blacklist.
1615 int ccw_purge_blacklisted(void)
1617 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1618 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1622 static void device_set_disconnected(struct ccw_device *cdev)
1626 ccw_device_set_timeout(cdev, 0);
1627 cdev->private->flags.fake_irb = 0;
1628 cdev->private->state = DEV_STATE_DISCONNECTED;
1630 ccw_device_schedule_recovery();
1633 void ccw_device_set_notoper(struct ccw_device *cdev)
1635 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1637 CIO_TRACE_EVENT(2, "notoper");
1638 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1639 ccw_device_set_timeout(cdev, 0);
1640 cio_disable_subchannel(sch);
1641 cdev->private->state = DEV_STATE_NOT_OPER;
1644 static int io_subchannel_sch_event(struct subchannel *sch, int slow)
1646 int event, ret, disc;
1647 unsigned long flags;
1648 enum { NONE, UNREGISTER, UNREGISTER_PROBE, REPROBE, DISC } action;
1649 struct ccw_device *cdev;
1651 spin_lock_irqsave(sch->lock, flags);
1652 cdev = sch_get_cdev(sch);
1653 disc = device_is_disconnected(cdev);
1655 /* Disconnected devices are evaluated directly only.*/
1656 spin_unlock_irqrestore(sch->lock, flags);
1659 /* No interrupt after machine check - kill pending timers. */
1661 ccw_device_set_timeout(cdev, 0);
1662 if (!disc && !slow) {
1663 /* Non-disconnected devices are evaluated on the slow path. */
1664 spin_unlock_irqrestore(sch->lock, flags);
1667 event = io_subchannel_get_status(sch);
1668 CIO_MSG_EVENT(4, "Evaluating schid 0.%x.%04x, event %d, %s, %s path.\n",
1669 sch->schid.ssid, sch->schid.sch_no, event,
1670 disc ? "disconnected" : "normal",
1671 slow ? "slow" : "fast");
1672 /* Analyze subchannel status. */
1677 /* Check if paths have become available. */
1683 /* Ask driver what to do with device. */
1684 if (io_subchannel_notify(sch, event))
1687 action = UNREGISTER;
1689 case CIO_REVALIDATE:
1690 /* Device will be removed, so no notify necessary. */
1692 /* Reprobe because immediate unregister might block. */
1695 action = UNREGISTER_PROBE;
1699 /* Get device operational again. */
1703 /* Perform action. */
1707 case UNREGISTER_PROBE:
1708 ccw_device_set_notoper(cdev);
1709 /* Unregister device (will use subchannel lock). */
1710 spin_unlock_irqrestore(sch->lock, flags);
1711 css_sch_device_unregister(sch);
1712 spin_lock_irqsave(sch->lock, flags);
1715 ccw_device_trigger_reprobe(cdev);
1718 device_set_disconnected(cdev);
1723 spin_unlock_irqrestore(sch->lock, flags);
1724 /* Probe if necessary. */
1725 if (action == UNREGISTER_PROBE)
1726 ret = css_probe_device(sch->schid);
1731 #ifdef CONFIG_CCW_CONSOLE
1732 static struct ccw_device console_cdev;
1733 static char console_cdev_name[10] = "0.x.xxxx";
1734 static struct ccw_device_private console_private;
1735 static int console_cdev_in_use;
1737 static DEFINE_SPINLOCK(ccw_console_lock);
1739 spinlock_t * cio_get_console_lock(void)
1741 return &ccw_console_lock;
1744 static int ccw_device_console_enable(struct ccw_device *cdev,
1745 struct subchannel *sch)
1749 /* Attach subchannel private data. */
1750 sch->private = cio_get_console_priv();
1751 memset(sch->private, 0, sizeof(struct io_subchannel_private));
1752 io_subchannel_init_fields(sch);
1753 rc = cio_commit_config(sch);
1756 sch->driver = &io_subchannel_driver;
1757 /* Initialize the ccw_device structure. */
1758 cdev->dev.parent= &sch->dev;
1759 rc = io_subchannel_recog(cdev, sch);
1763 /* Now wait for the async. recognition to come to an end. */
1764 spin_lock_irq(cdev->ccwlock);
1765 while (!dev_fsm_final_state(cdev))
1768 if (cdev->private->state != DEV_STATE_OFFLINE)
1770 ccw_device_online(cdev);
1771 while (!dev_fsm_final_state(cdev))
1773 if (cdev->private->state != DEV_STATE_ONLINE)
1777 spin_unlock_irq(cdev->ccwlock);
1782 ccw_device_probe_console(void)
1784 struct subchannel *sch;
1787 if (xchg(&console_cdev_in_use, 1) != 0)
1788 return ERR_PTR(-EBUSY);
1789 sch = cio_probe_console();
1791 console_cdev_in_use = 0;
1792 return (void *) sch;
1794 memset(&console_cdev, 0, sizeof(struct ccw_device));
1795 memset(&console_private, 0, sizeof(struct ccw_device_private));
1796 console_cdev.private = &console_private;
1797 console_private.cdev = &console_cdev;
1798 ret = ccw_device_console_enable(&console_cdev, sch);
1800 cio_release_console();
1801 console_cdev_in_use = 0;
1802 return ERR_PTR(ret);
1804 console_cdev.online = 1;
1805 return &console_cdev;
1808 static int ccw_device_pm_restore(struct device *dev);
1810 int ccw_device_force_console(void)
1812 if (!console_cdev_in_use)
1814 return ccw_device_pm_restore(&console_cdev.dev);
1816 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1818 const char *cio_get_console_cdev_name(struct subchannel *sch)
1820 snprintf(console_cdev_name, 10, "0.%x.%04x",
1821 sch->schid.ssid, sch->schib.pmcw.dev);
1822 return (const char *)console_cdev_name;
1827 * get ccw_device matching the busid, but only if owned by cdrv
1830 __ccwdev_check_busid(struct device *dev, void *id)
1836 return (strcmp(bus_id, dev_name(dev)) == 0);
1841 * get_ccwdev_by_busid() - obtain device from a bus id
1842 * @cdrv: driver the device is owned by
1843 * @bus_id: bus id of the device to be searched
1845 * This function searches all devices owned by @cdrv for a device with a bus
1846 * id matching @bus_id.
1848 * If a match is found, its reference count of the found device is increased
1849 * and it is returned; else %NULL is returned.
1851 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1855 struct device_driver *drv;
1857 drv = get_driver(&cdrv->driver);
1861 dev = driver_find_device(drv, NULL, (void *)bus_id,
1862 __ccwdev_check_busid);
1865 return dev ? to_ccwdev(dev) : NULL;
1868 /************************** device driver handling ************************/
1870 /* This is the implementation of the ccw_driver class. The probe, remove
1871 * and release methods are initially very similar to the device_driver
1872 * implementations, with the difference that they have ccw_device
1875 * A ccw driver also contains the information that is needed for
1879 ccw_device_probe (struct device *dev)
1881 struct ccw_device *cdev = to_ccwdev(dev);
1882 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1885 cdev->drv = cdrv; /* to let the driver call _set_online */
1887 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1898 ccw_device_remove (struct device *dev)
1900 struct ccw_device *cdev = to_ccwdev(dev);
1901 struct ccw_driver *cdrv = cdev->drv;
1908 spin_lock_irq(cdev->ccwlock);
1909 ret = ccw_device_offline(cdev);
1910 spin_unlock_irq(cdev->ccwlock);
1912 wait_event(cdev->private->wait_q,
1913 dev_fsm_final_state(cdev));
1915 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1916 "device 0.%x.%04x\n",
1917 ret, cdev->private->dev_id.ssid,
1918 cdev->private->dev_id.devno);
1919 /* Give up reference obtained in ccw_device_set_online(). */
1920 put_device(&cdev->dev);
1922 ccw_device_set_timeout(cdev, 0);
1927 static void ccw_device_shutdown(struct device *dev)
1929 struct ccw_device *cdev;
1931 cdev = to_ccwdev(dev);
1932 if (cdev->drv && cdev->drv->shutdown)
1933 cdev->drv->shutdown(cdev);
1937 static int ccw_device_pm_prepare(struct device *dev)
1939 struct ccw_device *cdev = to_ccwdev(dev);
1941 if (work_pending(&cdev->private->kick_work))
1943 /* Fail while device is being set online/offline. */
1944 if (atomic_read(&cdev->private->onoff))
1947 if (cdev->online && cdev->drv && cdev->drv->prepare)
1948 return cdev->drv->prepare(cdev);
1953 static void ccw_device_pm_complete(struct device *dev)
1955 struct ccw_device *cdev = to_ccwdev(dev);
1957 if (cdev->online && cdev->drv && cdev->drv->complete)
1958 cdev->drv->complete(cdev);
1961 static int ccw_device_pm_freeze(struct device *dev)
1963 struct ccw_device *cdev = to_ccwdev(dev);
1964 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1965 int ret, cm_enabled;
1967 /* Fail suspend while device is in transistional state. */
1968 if (!dev_fsm_final_state(cdev))
1972 if (cdev->drv && cdev->drv->freeze) {
1973 ret = cdev->drv->freeze(cdev);
1978 spin_lock_irq(sch->lock);
1979 cm_enabled = cdev->private->cmb != NULL;
1980 spin_unlock_irq(sch->lock);
1982 /* Don't have the css write on memory. */
1983 ret = ccw_set_cmf(cdev, 0);
1987 /* From here on, disallow device driver I/O. */
1988 spin_lock_irq(sch->lock);
1989 ret = cio_disable_subchannel(sch);
1990 spin_unlock_irq(sch->lock);
1995 static int ccw_device_pm_thaw(struct device *dev)
1997 struct ccw_device *cdev = to_ccwdev(dev);
1998 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1999 int ret, cm_enabled;
2004 spin_lock_irq(sch->lock);
2005 /* Allow device driver I/O again. */
2006 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
2007 cm_enabled = cdev->private->cmb != NULL;
2008 spin_unlock_irq(sch->lock);
2013 ret = ccw_set_cmf(cdev, 1);
2018 if (cdev->drv && cdev->drv->thaw)
2019 ret = cdev->drv->thaw(cdev);
2024 static void __ccw_device_pm_restore(struct ccw_device *cdev)
2026 struct subchannel *sch = to_subchannel(cdev->dev.parent);
2029 if (cio_is_console(sch->schid))
2032 * While we were sleeping, devices may have gone or become
2033 * available again. Kick re-detection.
2035 spin_lock_irq(sch->lock);
2036 cdev->private->flags.resuming = 1;
2037 ret = ccw_device_recognition(cdev);
2038 spin_unlock_irq(sch->lock);
2040 CIO_MSG_EVENT(0, "Couldn't start recognition for device "
2041 "0.%x.%04x (ret=%d)\n",
2042 cdev->private->dev_id.ssid,
2043 cdev->private->dev_id.devno, ret);
2044 spin_lock_irq(sch->lock);
2045 cdev->private->state = DEV_STATE_DISCONNECTED;
2046 spin_unlock_irq(sch->lock);
2047 /* notify driver after the resume cb */
2050 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
2051 cdev->private->state == DEV_STATE_DISCONNECTED);
2054 cdev->private->flags.resuming = 0;
2057 static int resume_handle_boxed(struct ccw_device *cdev)
2059 cdev->private->state = DEV_STATE_BOXED;
2060 if (ccw_device_notify(cdev, CIO_BOXED))
2062 ccw_device_schedule_sch_unregister(cdev);
2066 static int resume_handle_disc(struct ccw_device *cdev)
2068 cdev->private->state = DEV_STATE_DISCONNECTED;
2069 if (ccw_device_notify(cdev, CIO_GONE))
2071 ccw_device_schedule_sch_unregister(cdev);
2075 static int ccw_device_pm_restore(struct device *dev)
2077 struct ccw_device *cdev = to_ccwdev(dev);
2078 struct subchannel *sch = to_subchannel(cdev->dev.parent);
2079 int ret = 0, cm_enabled;
2081 __ccw_device_pm_restore(cdev);
2082 spin_lock_irq(sch->lock);
2083 if (cio_is_console(sch->schid)) {
2084 cio_enable_subchannel(sch, (u32)(addr_t)sch);
2085 spin_unlock_irq(sch->lock);
2088 cdev->private->flags.donotify = 0;
2089 /* check recognition results */
2090 switch (cdev->private->state) {
2091 case DEV_STATE_OFFLINE:
2093 case DEV_STATE_BOXED:
2094 ret = resume_handle_boxed(cdev);
2095 spin_unlock_irq(sch->lock);
2099 case DEV_STATE_DISCONNECTED:
2100 goto out_disc_unlock;
2102 goto out_unreg_unlock;
2104 /* check if the device id has changed */
2105 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
2106 CIO_MSG_EVENT(0, "resume: sch 0.%x.%04x: failed (devno "
2107 "changed from %04x to %04x)\n",
2108 sch->schid.ssid, sch->schid.sch_no,
2109 cdev->private->dev_id.devno,
2110 sch->schib.pmcw.dev);
2111 goto out_unreg_unlock;
2113 /* check if the device type has changed */
2114 if (!ccw_device_test_sense_data(cdev)) {
2115 ccw_device_update_sense_data(cdev);
2116 PREPARE_WORK(&cdev->private->kick_work,
2117 ccw_device_do_unbind_bind);
2118 queue_work(ccw_device_work, &cdev->private->kick_work);
2122 if (!cdev->online) {
2126 ret = ccw_device_online(cdev);
2128 goto out_disc_unlock;
2130 cm_enabled = cdev->private->cmb != NULL;
2131 spin_unlock_irq(sch->lock);
2133 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
2134 if (cdev->private->state != DEV_STATE_ONLINE) {
2135 spin_lock_irq(sch->lock);
2136 goto out_disc_unlock;
2139 ret = ccw_set_cmf(cdev, 1);
2141 CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2142 "(rc=%d)\n", cdev->private->dev_id.ssid,
2143 cdev->private->dev_id.devno, ret);
2149 if (cdev->online && cdev->drv && cdev->drv->restore)
2150 ret = cdev->drv->restore(cdev);
2155 ret = resume_handle_disc(cdev);
2156 spin_unlock_irq(sch->lock);
2162 ccw_device_schedule_sch_unregister(cdev);
2165 spin_unlock_irq(sch->lock);
2169 static struct dev_pm_ops ccw_pm_ops = {
2170 .prepare = ccw_device_pm_prepare,
2171 .complete = ccw_device_pm_complete,
2172 .freeze = ccw_device_pm_freeze,
2173 .thaw = ccw_device_pm_thaw,
2174 .restore = ccw_device_pm_restore,
2177 struct bus_type ccw_bus_type = {
2179 .match = ccw_bus_match,
2180 .uevent = ccw_uevent,
2181 .probe = ccw_device_probe,
2182 .remove = ccw_device_remove,
2183 .shutdown = ccw_device_shutdown,
2188 * ccw_driver_register() - register a ccw driver
2189 * @cdriver: driver to be registered
2191 * This function is mainly a wrapper around driver_register().
2193 * %0 on success and a negative error value on failure.
2195 int ccw_driver_register(struct ccw_driver *cdriver)
2197 struct device_driver *drv = &cdriver->driver;
2199 drv->bus = &ccw_bus_type;
2200 drv->name = cdriver->name;
2201 drv->owner = cdriver->owner;
2203 return driver_register(drv);
2207 * ccw_driver_unregister() - deregister a ccw driver
2208 * @cdriver: driver to be deregistered
2210 * This function is mainly a wrapper around driver_unregister().
2212 void ccw_driver_unregister(struct ccw_driver *cdriver)
2214 driver_unregister(&cdriver->driver);
2217 /* Helper func for qdio. */
2218 struct subchannel_id
2219 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2221 struct subchannel *sch;
2223 sch = to_subchannel(cdev->dev.parent);
2227 MODULE_LICENSE("GPL");
2228 EXPORT_SYMBOL(ccw_device_set_online);
2229 EXPORT_SYMBOL(ccw_device_set_offline);
2230 EXPORT_SYMBOL(ccw_driver_register);
2231 EXPORT_SYMBOL(ccw_driver_unregister);
2232 EXPORT_SYMBOL(get_ccwdev_by_busid);
2233 EXPORT_SYMBOL(ccw_bus_type);
2234 EXPORT_SYMBOL(ccw_device_work);
2235 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);