2 * drivers/s390/cio/device.c
3 * bus driver for ccw devices
5 * Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
7 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
8 * Cornelia Huck (cornelia.huck@de.ibm.com)
9 * Martin Schwidefsky (schwidefsky@de.ibm.com)
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/spinlock.h>
14 #include <linux/errno.h>
15 #include <linux/err.h>
16 #include <linux/slab.h>
17 #include <linux/list.h>
18 #include <linux/device.h>
19 #include <linux/workqueue.h>
20 #include <linux/timer.h>
22 #include <asm/ccwdev.h>
24 #include <asm/param.h> /* HZ */
28 #include "cio_debug.h"
34 static struct timer_list recovery_timer;
35 static spinlock_t recovery_lock;
36 static int recovery_phase;
37 static const unsigned long recovery_delay[] = { 3, 30, 300 };
39 /******************* bus type handling ***********************/
41 /* The Linux driver model distinguishes between a bus type and
42 * the bus itself. Of course we only have one channel
43 * subsystem driver and one channel system per machine, but
44 * we still use the abstraction. T.R. says it's a good idea. */
46 ccw_bus_match (struct device * dev, struct device_driver * drv)
48 struct ccw_device *cdev = to_ccwdev(dev);
49 struct ccw_driver *cdrv = to_ccwdrv(drv);
50 const struct ccw_device_id *ids = cdrv->ids, *found;
55 found = ccw_device_id_match(ids, &cdev->id);
59 cdev->id.driver_info = found->driver_info;
64 /* Store modalias string delimited by prefix/suffix string into buffer with
65 * specified size. Return length of resulting string (excluding trailing '\0')
66 * even if string doesn't fit buffer (snprintf semantics). */
67 static int snprint_alias(char *buf, size_t size,
68 struct ccw_device_id *id, const char *suffix)
72 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
78 if (id->dev_type != 0)
79 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
80 id->dev_model, suffix);
82 len += snprintf(buf, size, "dtdm%s", suffix);
87 /* Set up environment variables for ccw device uevent. Return 0 on success,
88 * non-zero otherwise. */
89 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
91 struct ccw_device *cdev = to_ccwdev(dev);
92 struct ccw_device_id *id = &(cdev->id);
94 char modalias_buf[30];
97 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
102 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
106 /* The next two can be zero, that's ok for us */
108 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
113 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
118 snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
119 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
123 struct bus_type ccw_bus_type;
125 static void io_subchannel_irq(struct subchannel *);
126 static int io_subchannel_probe(struct subchannel *);
127 static int io_subchannel_remove(struct subchannel *);
128 static int io_subchannel_notify(struct subchannel *, int);
129 static void io_subchannel_verify(struct subchannel *);
130 static void io_subchannel_ioterm(struct subchannel *);
131 static void io_subchannel_shutdown(struct subchannel *);
133 static struct css_driver io_subchannel_driver = {
134 .owner = THIS_MODULE,
135 .subchannel_type = SUBCHANNEL_TYPE_IO,
136 .name = "io_subchannel",
137 .irq = io_subchannel_irq,
138 .notify = io_subchannel_notify,
139 .verify = io_subchannel_verify,
140 .termination = io_subchannel_ioterm,
141 .probe = io_subchannel_probe,
142 .remove = io_subchannel_remove,
143 .shutdown = io_subchannel_shutdown,
146 struct workqueue_struct *ccw_device_work;
147 struct workqueue_struct *ccw_device_notify_work;
148 wait_queue_head_t ccw_device_init_wq;
149 atomic_t ccw_device_init_count;
151 static void recovery_func(unsigned long data);
154 init_ccw_bus_type (void)
158 init_waitqueue_head(&ccw_device_init_wq);
159 atomic_set(&ccw_device_init_count, 0);
160 setup_timer(&recovery_timer, recovery_func, 0);
162 ccw_device_work = create_singlethread_workqueue("cio");
163 if (!ccw_device_work)
164 return -ENOMEM; /* FIXME: better errno ? */
165 ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
166 if (!ccw_device_notify_work) {
167 ret = -ENOMEM; /* FIXME: better errno ? */
170 slow_path_wq = create_singlethread_workqueue("kslowcrw");
172 ret = -ENOMEM; /* FIXME: better errno ? */
175 if ((ret = bus_register (&ccw_bus_type)))
178 ret = css_driver_register(&io_subchannel_driver);
182 wait_event(ccw_device_init_wq,
183 atomic_read(&ccw_device_init_count) == 0);
184 flush_workqueue(ccw_device_work);
188 destroy_workqueue(ccw_device_work);
189 if (ccw_device_notify_work)
190 destroy_workqueue(ccw_device_notify_work);
192 destroy_workqueue(slow_path_wq);
197 cleanup_ccw_bus_type (void)
199 css_driver_unregister(&io_subchannel_driver);
200 bus_unregister(&ccw_bus_type);
201 destroy_workqueue(ccw_device_notify_work);
202 destroy_workqueue(ccw_device_work);
205 subsys_initcall(init_ccw_bus_type);
206 module_exit(cleanup_ccw_bus_type);
208 /************************ device handling **************************/
211 * A ccw_device has some interfaces in sysfs in addition to the
213 * The following entries are designed to export the information which
214 * resided in 2.4 in /proc/subchannels. Subchannel and device number
215 * are obvious, so they don't have an entry :)
216 * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
219 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
221 struct subchannel *sch = to_subchannel(dev);
222 struct chsc_ssd_info *ssd = &sch->ssd_info;
227 for (chp = 0; chp < 8; chp++) {
229 if (ssd->path_mask & mask)
230 ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
232 ret += sprintf(buf + ret, "00 ");
234 ret += sprintf (buf+ret, "\n");
235 return min((ssize_t)PAGE_SIZE, ret);
239 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
241 struct subchannel *sch = to_subchannel(dev);
242 struct pmcw *pmcw = &sch->schib.pmcw;
244 return sprintf (buf, "%02x %02x %02x\n",
245 pmcw->pim, pmcw->pam, pmcw->pom);
249 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
251 struct ccw_device *cdev = to_ccwdev(dev);
252 struct ccw_device_id *id = &(cdev->id);
254 if (id->dev_type != 0)
255 return sprintf(buf, "%04x/%02x\n",
256 id->dev_type, id->dev_model);
258 return sprintf(buf, "n/a\n");
262 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
264 struct ccw_device *cdev = to_ccwdev(dev);
265 struct ccw_device_id *id = &(cdev->id);
267 return sprintf(buf, "%04x/%02x\n",
268 id->cu_type, id->cu_model);
272 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
274 struct ccw_device *cdev = to_ccwdev(dev);
275 struct ccw_device_id *id = &(cdev->id);
278 len = snprint_alias(buf, PAGE_SIZE, id, "\n");
280 return len > PAGE_SIZE ? PAGE_SIZE : len;
284 online_show (struct device *dev, struct device_attribute *attr, char *buf)
286 struct ccw_device *cdev = to_ccwdev(dev);
288 return sprintf(buf, cdev->online ? "1\n" : "0\n");
291 int ccw_device_is_orphan(struct ccw_device *cdev)
293 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
296 static void ccw_device_unregister(struct ccw_device *cdev)
298 if (test_and_clear_bit(1, &cdev->private->registered))
299 device_del(&cdev->dev);
302 static void ccw_device_remove_orphan_cb(struct device *dev)
304 struct ccw_device *cdev = to_ccwdev(dev);
306 ccw_device_unregister(cdev);
307 put_device(&cdev->dev);
310 static void ccw_device_remove_sch_cb(struct device *dev)
312 struct subchannel *sch;
314 sch = to_subchannel(dev);
315 css_sch_device_unregister(sch);
316 /* Reset intparm to zeroes. */
317 sch->schib.pmcw.intparm = 0;
319 put_device(&sch->dev);
323 ccw_device_remove_disconnected(struct ccw_device *cdev)
329 * Forced offline in disconnected state means
330 * 'throw away device'.
332 if (ccw_device_is_orphan(cdev)) {
334 * Deregister ccw device.
335 * Unfortunately, we cannot do this directly from the
338 spin_lock_irqsave(cdev->ccwlock, flags);
339 cdev->private->state = DEV_STATE_NOT_OPER;
340 spin_unlock_irqrestore(cdev->ccwlock, flags);
341 rc = device_schedule_callback(&cdev->dev,
342 ccw_device_remove_orphan_cb);
344 CIO_MSG_EVENT(2, "Couldn't unregister orphan "
346 cdev->private->dev_id.ssid,
347 cdev->private->dev_id.devno);
350 /* Deregister subchannel, which will kill the ccw device. */
351 rc = device_schedule_callback(cdev->dev.parent,
352 ccw_device_remove_sch_cb);
354 CIO_MSG_EVENT(2, "Couldn't unregister disconnected device "
356 cdev->private->dev_id.ssid,
357 cdev->private->dev_id.devno);
361 * ccw_device_set_offline() - disable a ccw device for I/O
362 * @cdev: target ccw device
364 * This function calls the driver's set_offline() function for @cdev, if
365 * given, and then disables @cdev.
367 * %0 on success and a negative error value on failure.
369 * enabled, ccw device lock not held
371 int ccw_device_set_offline(struct ccw_device *cdev)
377 if (!cdev->online || !cdev->drv)
380 if (cdev->drv->set_offline) {
381 ret = cdev->drv->set_offline(cdev);
386 spin_lock_irq(cdev->ccwlock);
387 ret = ccw_device_offline(cdev);
388 if (ret == -ENODEV) {
389 if (cdev->private->state != DEV_STATE_NOT_OPER) {
390 cdev->private->state = DEV_STATE_OFFLINE;
391 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
393 spin_unlock_irq(cdev->ccwlock);
396 spin_unlock_irq(cdev->ccwlock);
398 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
400 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
401 "device 0.%x.%04x\n",
402 ret, cdev->private->dev_id.ssid,
403 cdev->private->dev_id.devno);
410 * ccw_device_set_online() - enable a ccw device for I/O
411 * @cdev: target ccw device
413 * This function first enables @cdev and then calls the driver's set_online()
414 * function for @cdev, if given. If set_online() returns an error, @cdev is
417 * %0 on success and a negative error value on failure.
419 * enabled, ccw device lock not held
421 int ccw_device_set_online(struct ccw_device *cdev)
427 if (cdev->online || !cdev->drv)
430 spin_lock_irq(cdev->ccwlock);
431 ret = ccw_device_online(cdev);
432 spin_unlock_irq(cdev->ccwlock);
434 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
436 CIO_MSG_EVENT(2, "ccw_device_online returned %d, "
437 "device 0.%x.%04x\n",
438 ret, cdev->private->dev_id.ssid,
439 cdev->private->dev_id.devno);
442 if (cdev->private->state != DEV_STATE_ONLINE)
444 if (!cdev->drv->set_online || cdev->drv->set_online(cdev) == 0) {
448 spin_lock_irq(cdev->ccwlock);
449 ret = ccw_device_offline(cdev);
450 spin_unlock_irq(cdev->ccwlock);
452 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
454 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
455 "device 0.%x.%04x\n",
456 ret, cdev->private->dev_id.ssid,
457 cdev->private->dev_id.devno);
458 return (ret == 0) ? -ENODEV : ret;
461 static void online_store_handle_offline(struct ccw_device *cdev)
463 if (cdev->private->state == DEV_STATE_DISCONNECTED)
464 ccw_device_remove_disconnected(cdev);
465 else if (cdev->drv && cdev->drv->set_offline)
466 ccw_device_set_offline(cdev);
469 static int online_store_recog_and_online(struct ccw_device *cdev)
473 /* Do device recognition, if needed. */
474 if (cdev->id.cu_type == 0) {
475 ret = ccw_device_recognition(cdev);
477 CIO_MSG_EVENT(0, "Couldn't start recognition "
478 "for device 0.%x.%04x (ret=%d)\n",
479 cdev->private->dev_id.ssid,
480 cdev->private->dev_id.devno, ret);
483 wait_event(cdev->private->wait_q,
484 cdev->private->flags.recog_done);
486 if (cdev->drv && cdev->drv->set_online)
487 ccw_device_set_online(cdev);
490 static void online_store_handle_online(struct ccw_device *cdev, int force)
494 ret = online_store_recog_and_online(cdev);
497 if (force && cdev->private->state == DEV_STATE_BOXED) {
498 ret = ccw_device_stlck(cdev);
501 "ccw_device_stlck returned %d!\n", ret);
504 if (cdev->id.cu_type == 0)
505 cdev->private->state = DEV_STATE_NOT_OPER;
506 online_store_recog_and_online(cdev);
511 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
512 const char *buf, size_t count)
514 struct ccw_device *cdev = to_ccwdev(dev);
518 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
521 if (cdev->drv && !try_module_get(cdev->drv->owner)) {
522 atomic_set(&cdev->private->onoff, 0);
525 if (!strncmp(buf, "force\n", count)) {
530 i = simple_strtoul(buf, &tmp, 16);
535 online_store_handle_offline(cdev);
538 online_store_handle_online(cdev, force);
544 module_put(cdev->drv->owner);
545 atomic_set(&cdev->private->onoff, 0);
550 available_show (struct device *dev, struct device_attribute *attr, char *buf)
552 struct ccw_device *cdev = to_ccwdev(dev);
553 struct subchannel *sch;
555 if (ccw_device_is_orphan(cdev))
556 return sprintf(buf, "no device\n");
557 switch (cdev->private->state) {
558 case DEV_STATE_BOXED:
559 return sprintf(buf, "boxed\n");
560 case DEV_STATE_DISCONNECTED:
561 case DEV_STATE_DISCONNECTED_SENSE_ID:
562 case DEV_STATE_NOT_OPER:
563 sch = to_subchannel(dev->parent);
565 return sprintf(buf, "no path\n");
567 return sprintf(buf, "no device\n");
569 /* All other states considered fine. */
570 return sprintf(buf, "good\n");
574 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
575 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
576 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
577 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
578 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
579 static DEVICE_ATTR(online, 0644, online_show, online_store);
580 extern struct device_attribute dev_attr_cmb_enable;
581 static DEVICE_ATTR(availability, 0444, available_show, NULL);
583 static struct attribute * subch_attrs[] = {
584 &dev_attr_chpids.attr,
585 &dev_attr_pimpampom.attr,
589 static struct attribute_group subch_attr_group = {
590 .attrs = subch_attrs,
593 struct attribute_group *subch_attr_groups[] = {
598 static struct attribute * ccwdev_attrs[] = {
599 &dev_attr_devtype.attr,
600 &dev_attr_cutype.attr,
601 &dev_attr_modalias.attr,
602 &dev_attr_online.attr,
603 &dev_attr_cmb_enable.attr,
604 &dev_attr_availability.attr,
608 static struct attribute_group ccwdev_attr_group = {
609 .attrs = ccwdev_attrs,
612 static struct attribute_group *ccwdev_attr_groups[] = {
617 /* this is a simple abstraction for device_register that sets the
618 * correct bus type and adds the bus specific files */
619 static int ccw_device_register(struct ccw_device *cdev)
621 struct device *dev = &cdev->dev;
624 dev->bus = &ccw_bus_type;
626 if ((ret = device_add(dev)))
629 set_bit(1, &cdev->private->registered);
634 struct ccw_dev_id dev_id;
635 struct ccw_device * sibling;
639 match_devno(struct device * dev, void * data)
641 struct match_data * d = data;
642 struct ccw_device * cdev;
644 cdev = to_ccwdev(dev);
645 if ((cdev->private->state == DEV_STATE_DISCONNECTED) &&
646 !ccw_device_is_orphan(cdev) &&
647 ccw_dev_id_is_equal(&cdev->private->dev_id, &d->dev_id) &&
648 (cdev != d->sibling))
653 static struct ccw_device * get_disc_ccwdev_by_dev_id(struct ccw_dev_id *dev_id,
654 struct ccw_device *sibling)
657 struct match_data data;
659 data.dev_id = *dev_id;
660 data.sibling = sibling;
661 dev = bus_find_device(&ccw_bus_type, NULL, &data, match_devno);
663 return dev ? to_ccwdev(dev) : NULL;
666 static int match_orphan(struct device *dev, void *data)
668 struct ccw_dev_id *dev_id;
669 struct ccw_device *cdev;
672 cdev = to_ccwdev(dev);
673 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
676 static struct ccw_device *
677 get_orphaned_ccwdev_by_dev_id(struct channel_subsystem *css,
678 struct ccw_dev_id *dev_id)
682 dev = device_find_child(&css->pseudo_subchannel->dev, dev_id,
685 return dev ? to_ccwdev(dev) : NULL;
689 ccw_device_add_changed(struct work_struct *work)
691 struct ccw_device_private *priv;
692 struct ccw_device *cdev;
694 priv = container_of(work, struct ccw_device_private, kick_work);
696 if (device_add(&cdev->dev)) {
697 put_device(&cdev->dev);
700 set_bit(1, &cdev->private->registered);
703 void ccw_device_do_unreg_rereg(struct work_struct *work)
705 struct ccw_device_private *priv;
706 struct ccw_device *cdev;
707 struct subchannel *sch;
709 priv = container_of(work, struct ccw_device_private, kick_work);
711 sch = to_subchannel(cdev->dev.parent);
713 ccw_device_unregister(cdev);
714 PREPARE_WORK(&cdev->private->kick_work,
715 ccw_device_add_changed);
716 queue_work(ccw_device_work, &cdev->private->kick_work);
720 ccw_device_release(struct device *dev)
722 struct ccw_device *cdev;
724 cdev = to_ccwdev(dev);
725 kfree(cdev->private);
729 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
731 struct ccw_device *cdev;
733 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
735 cdev->private = kzalloc(sizeof(struct ccw_device_private),
736 GFP_KERNEL | GFP_DMA);
741 return ERR_PTR(-ENOMEM);
744 static int io_subchannel_initialize_dev(struct subchannel *sch,
745 struct ccw_device *cdev)
747 cdev->private->cdev = cdev;
748 atomic_set(&cdev->private->onoff, 0);
749 cdev->dev.parent = &sch->dev;
750 cdev->dev.release = ccw_device_release;
751 INIT_WORK(&cdev->private->kick_work, NULL);
752 cdev->dev.groups = ccwdev_attr_groups;
753 /* Do first half of device_register. */
754 device_initialize(&cdev->dev);
755 if (!get_device(&sch->dev)) {
756 if (cdev->dev.release)
757 cdev->dev.release(&cdev->dev);
763 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
765 struct ccw_device *cdev;
768 cdev = io_subchannel_allocate_dev(sch);
770 ret = io_subchannel_initialize_dev(sch, cdev);
779 static int io_subchannel_recog(struct ccw_device *, struct subchannel *);
781 static void sch_attach_device(struct subchannel *sch,
782 struct ccw_device *cdev)
784 css_update_ssd_info(sch);
785 spin_lock_irq(sch->lock);
786 sch_set_cdev(sch, cdev);
787 cdev->private->schid = sch->schid;
788 cdev->ccwlock = sch->lock;
789 device_trigger_reprobe(sch);
790 spin_unlock_irq(sch->lock);
793 static void sch_attach_disconnected_device(struct subchannel *sch,
794 struct ccw_device *cdev)
796 struct subchannel *other_sch;
799 other_sch = to_subchannel(get_device(cdev->dev.parent));
800 ret = device_move(&cdev->dev, &sch->dev);
802 CIO_MSG_EVENT(2, "Moving disconnected device 0.%x.%04x failed "
803 "(ret=%d)!\n", cdev->private->dev_id.ssid,
804 cdev->private->dev_id.devno, ret);
805 put_device(&other_sch->dev);
808 sch_set_cdev(other_sch, NULL);
809 /* No need to keep a subchannel without ccw device around. */
810 css_sch_device_unregister(other_sch);
811 put_device(&other_sch->dev);
812 sch_attach_device(sch, cdev);
815 static void sch_attach_orphaned_device(struct subchannel *sch,
816 struct ccw_device *cdev)
820 /* Try to move the ccw device to its new subchannel. */
821 ret = device_move(&cdev->dev, &sch->dev);
823 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x from orphanage "
824 "failed (ret=%d)!\n",
825 cdev->private->dev_id.ssid,
826 cdev->private->dev_id.devno, ret);
829 sch_attach_device(sch, cdev);
832 static void sch_create_and_recog_new_device(struct subchannel *sch)
834 struct ccw_device *cdev;
836 /* Need to allocate a new ccw device. */
837 cdev = io_subchannel_create_ccwdev(sch);
839 /* OK, we did everything we could... */
840 css_sch_device_unregister(sch);
843 spin_lock_irq(sch->lock);
844 sch_set_cdev(sch, cdev);
845 spin_unlock_irq(sch->lock);
846 /* Start recognition for the new ccw device. */
847 if (io_subchannel_recog(cdev, sch)) {
848 spin_lock_irq(sch->lock);
849 sch_set_cdev(sch, NULL);
850 spin_unlock_irq(sch->lock);
851 if (cdev->dev.release)
852 cdev->dev.release(&cdev->dev);
853 css_sch_device_unregister(sch);
858 void ccw_device_move_to_orphanage(struct work_struct *work)
860 struct ccw_device_private *priv;
861 struct ccw_device *cdev;
862 struct ccw_device *replacing_cdev;
863 struct subchannel *sch;
865 struct channel_subsystem *css;
866 struct ccw_dev_id dev_id;
868 priv = container_of(work, struct ccw_device_private, kick_work);
870 sch = to_subchannel(cdev->dev.parent);
871 css = to_css(sch->dev.parent);
872 dev_id.devno = sch->schib.pmcw.dev;
873 dev_id.ssid = sch->schid.ssid;
876 * Move the orphaned ccw device to the orphanage so the replacing
877 * ccw device can take its place on the subchannel.
879 ret = device_move(&cdev->dev, &css->pseudo_subchannel->dev);
881 CIO_MSG_EVENT(0, "Moving device 0.%x.%04x to orphanage failed "
882 "(ret=%d)!\n", cdev->private->dev_id.ssid,
883 cdev->private->dev_id.devno, ret);
886 cdev->ccwlock = css->pseudo_subchannel->lock;
888 * Search for the replacing ccw device
889 * - among the disconnected devices
892 replacing_cdev = get_disc_ccwdev_by_dev_id(&dev_id, cdev);
893 if (replacing_cdev) {
894 sch_attach_disconnected_device(sch, replacing_cdev);
897 replacing_cdev = get_orphaned_ccwdev_by_dev_id(css, &dev_id);
898 if (replacing_cdev) {
899 sch_attach_orphaned_device(sch, replacing_cdev);
902 sch_create_and_recog_new_device(sch);
906 * Register recognized device.
909 io_subchannel_register(struct work_struct *work)
911 struct ccw_device_private *priv;
912 struct ccw_device *cdev;
913 struct subchannel *sch;
917 priv = container_of(work, struct ccw_device_private, kick_work);
919 sch = to_subchannel(cdev->dev.parent);
920 css_update_ssd_info(sch);
922 * io_subchannel_register() will also be called after device
923 * recognition has been done for a boxed device (which will already
924 * be registered). We need to reprobe since we may now have sense id
927 if (klist_node_attached(&cdev->dev.knode_parent)) {
929 ret = device_reprobe(&cdev->dev);
931 /* We can't do much here. */
932 CIO_MSG_EVENT(2, "device_reprobe() returned"
933 " %d for 0.%x.%04x\n", ret,
934 cdev->private->dev_id.ssid,
935 cdev->private->dev_id.devno);
940 * Now we know this subchannel will stay, we can throw
941 * our delayed uevent.
943 sch->dev.uevent_suppress = 0;
944 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
945 /* make it known to the system */
946 ret = ccw_device_register(cdev);
948 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
949 cdev->private->dev_id.ssid,
950 cdev->private->dev_id.devno, ret);
951 put_device(&cdev->dev);
952 spin_lock_irqsave(sch->lock, flags);
953 sch_set_cdev(sch, NULL);
954 spin_unlock_irqrestore(sch->lock, flags);
955 kfree (cdev->private);
957 put_device(&sch->dev);
958 if (atomic_dec_and_test(&ccw_device_init_count))
959 wake_up(&ccw_device_init_wq);
962 put_device(&cdev->dev);
964 cdev->private->flags.recog_done = 1;
965 put_device(&sch->dev);
966 wake_up(&cdev->private->wait_q);
967 if (atomic_dec_and_test(&ccw_device_init_count))
968 wake_up(&ccw_device_init_wq);
971 static void ccw_device_call_sch_unregister(struct work_struct *work)
973 struct ccw_device_private *priv;
974 struct ccw_device *cdev;
975 struct subchannel *sch;
977 priv = container_of(work, struct ccw_device_private, kick_work);
979 sch = to_subchannel(cdev->dev.parent);
980 css_sch_device_unregister(sch);
981 /* Reset intparm to zeroes. */
982 sch->schib.pmcw.intparm = 0;
984 put_device(&cdev->dev);
985 put_device(&sch->dev);
989 * subchannel recognition done. Called from the state machine.
992 io_subchannel_recog_done(struct ccw_device *cdev)
994 struct subchannel *sch;
996 if (css_init_done == 0) {
997 cdev->private->flags.recog_done = 1;
1000 switch (cdev->private->state) {
1001 case DEV_STATE_NOT_OPER:
1002 cdev->private->flags.recog_done = 1;
1003 /* Remove device found not operational. */
1004 if (!get_device(&cdev->dev))
1006 sch = to_subchannel(cdev->dev.parent);
1007 PREPARE_WORK(&cdev->private->kick_work,
1008 ccw_device_call_sch_unregister);
1009 queue_work(slow_path_wq, &cdev->private->kick_work);
1010 if (atomic_dec_and_test(&ccw_device_init_count))
1011 wake_up(&ccw_device_init_wq);
1013 case DEV_STATE_BOXED:
1014 /* Device did not respond in time. */
1015 case DEV_STATE_OFFLINE:
1017 * We can't register the device in interrupt context so
1018 * we schedule a work item.
1020 if (!get_device(&cdev->dev))
1022 PREPARE_WORK(&cdev->private->kick_work,
1023 io_subchannel_register);
1024 queue_work(slow_path_wq, &cdev->private->kick_work);
1030 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1033 struct ccw_device_private *priv;
1035 sch_set_cdev(sch, cdev);
1036 sch->driver = &io_subchannel_driver;
1037 cdev->ccwlock = sch->lock;
1039 /* Init private data. */
1040 priv = cdev->private;
1041 priv->dev_id.devno = sch->schib.pmcw.dev;
1042 priv->dev_id.ssid = sch->schid.ssid;
1043 priv->schid = sch->schid;
1044 priv->state = DEV_STATE_NOT_OPER;
1045 INIT_LIST_HEAD(&priv->cmb_list);
1046 init_waitqueue_head(&priv->wait_q);
1047 init_timer(&priv->timer);
1049 /* Set an initial name for the device. */
1050 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1051 sch->schid.ssid, sch->schib.pmcw.dev);
1053 /* Increase counter of devices currently in recognition. */
1054 atomic_inc(&ccw_device_init_count);
1056 /* Start async. device sensing. */
1057 spin_lock_irq(sch->lock);
1058 rc = ccw_device_recognition(cdev);
1059 spin_unlock_irq(sch->lock);
1061 if (atomic_dec_and_test(&ccw_device_init_count))
1062 wake_up(&ccw_device_init_wq);
1067 static void ccw_device_move_to_sch(struct work_struct *work)
1069 struct ccw_device_private *priv;
1071 struct subchannel *sch;
1072 struct ccw_device *cdev;
1073 struct subchannel *former_parent;
1075 priv = container_of(work, struct ccw_device_private, kick_work);
1078 former_parent = ccw_device_is_orphan(cdev) ?
1079 NULL : to_subchannel(get_device(cdev->dev.parent));
1080 mutex_lock(&sch->reg_mutex);
1081 /* Try to move the ccw device to its new subchannel. */
1082 rc = device_move(&cdev->dev, &sch->dev);
1083 mutex_unlock(&sch->reg_mutex);
1085 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1086 "0.%x.%04x failed (ret=%d)!\n",
1087 cdev->private->dev_id.ssid,
1088 cdev->private->dev_id.devno, sch->schid.ssid,
1089 sch->schid.sch_no, rc);
1090 css_sch_device_unregister(sch);
1093 if (former_parent) {
1094 spin_lock_irq(former_parent->lock);
1095 sch_set_cdev(former_parent, NULL);
1096 spin_unlock_irq(former_parent->lock);
1097 css_sch_device_unregister(former_parent);
1098 /* Reset intparm to zeroes. */
1099 former_parent->schib.pmcw.intparm = 0;
1100 cio_modify(former_parent);
1102 sch_attach_device(sch, cdev);
1105 put_device(&former_parent->dev);
1106 put_device(&cdev->dev);
1109 static void io_subchannel_irq(struct subchannel *sch)
1111 struct ccw_device *cdev;
1113 cdev = sch_get_cdev(sch);
1115 CIO_TRACE_EVENT(3, "IRQ");
1116 CIO_TRACE_EVENT(3, sch->dev.bus_id);
1118 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1122 io_subchannel_probe (struct subchannel *sch)
1124 struct ccw_device *cdev;
1126 unsigned long flags;
1127 struct ccw_dev_id dev_id;
1129 cdev = sch_get_cdev(sch);
1132 * This subchannel already has an associated ccw_device.
1133 * Register it and exit. This happens for all early
1134 * device, e.g. the console.
1136 cdev->dev.groups = ccwdev_attr_groups;
1137 device_initialize(&cdev->dev);
1138 ccw_device_register(cdev);
1140 * Check if the device is already online. If it is
1141 * the reference count needs to be corrected
1142 * (see ccw_device_online and css_init_done for the
1145 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1146 cdev->private->state != DEV_STATE_OFFLINE &&
1147 cdev->private->state != DEV_STATE_BOXED)
1148 get_device(&cdev->dev);
1152 * First check if a fitting device may be found amongst the
1153 * disconnected devices or in the orphanage.
1155 dev_id.devno = sch->schib.pmcw.dev;
1156 dev_id.ssid = sch->schid.ssid;
1157 /* Allocate I/O subchannel private data. */
1158 sch->private = kzalloc(sizeof(struct io_subchannel_private),
1159 GFP_KERNEL | GFP_DMA);
1162 cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1164 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1168 * Schedule moving the device until when we have a registered
1169 * subchannel to move to and succeed the probe. We can
1170 * unregister later again, when the probe is through.
1172 cdev->private->sch = sch;
1173 PREPARE_WORK(&cdev->private->kick_work,
1174 ccw_device_move_to_sch);
1175 queue_work(slow_path_wq, &cdev->private->kick_work);
1178 cdev = io_subchannel_create_ccwdev(sch);
1180 kfree(sch->private);
1181 return PTR_ERR(cdev);
1183 rc = io_subchannel_recog(cdev, sch);
1185 spin_lock_irqsave(sch->lock, flags);
1186 sch_set_cdev(sch, NULL);
1187 spin_unlock_irqrestore(sch->lock, flags);
1188 if (cdev->dev.release)
1189 cdev->dev.release(&cdev->dev);
1190 kfree(sch->private);
1197 io_subchannel_remove (struct subchannel *sch)
1199 struct ccw_device *cdev;
1200 unsigned long flags;
1202 cdev = sch_get_cdev(sch);
1205 /* Set ccw device to not operational and drop reference. */
1206 spin_lock_irqsave(cdev->ccwlock, flags);
1207 sch_set_cdev(sch, NULL);
1208 cdev->private->state = DEV_STATE_NOT_OPER;
1209 spin_unlock_irqrestore(cdev->ccwlock, flags);
1210 ccw_device_unregister(cdev);
1211 put_device(&cdev->dev);
1212 kfree(sch->private);
1216 static int io_subchannel_notify(struct subchannel *sch, int event)
1218 struct ccw_device *cdev;
1220 cdev = sch_get_cdev(sch);
1227 return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1230 static void io_subchannel_verify(struct subchannel *sch)
1232 struct ccw_device *cdev;
1234 cdev = sch_get_cdev(sch);
1236 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1239 static void io_subchannel_ioterm(struct subchannel *sch)
1241 struct ccw_device *cdev;
1243 cdev = sch_get_cdev(sch);
1246 /* Internal I/O will be retried by the interrupt handler. */
1247 if (cdev->private->flags.intretry)
1249 cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1251 cdev->handler(cdev, cdev->private->intparm,
1256 io_subchannel_shutdown(struct subchannel *sch)
1258 struct ccw_device *cdev;
1261 cdev = sch_get_cdev(sch);
1263 if (cio_is_console(sch->schid))
1265 if (!sch->schib.pmcw.ena)
1266 /* Nothing to do. */
1268 ret = cio_disable_subchannel(sch);
1270 /* Subchannel is disabled, we're done. */
1272 cdev->private->state = DEV_STATE_QUIESCE;
1274 cdev->handler(cdev, cdev->private->intparm,
1276 ret = ccw_device_cancel_halt_clear(cdev);
1277 if (ret == -EBUSY) {
1278 ccw_device_set_timeout(cdev, HZ/10);
1279 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1281 cio_disable_subchannel(sch);
1284 #ifdef CONFIG_CCW_CONSOLE
1285 static struct ccw_device console_cdev;
1286 static struct ccw_device_private console_private;
1287 static int console_cdev_in_use;
1289 static DEFINE_SPINLOCK(ccw_console_lock);
1291 spinlock_t * cio_get_console_lock(void)
1293 return &ccw_console_lock;
1297 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1301 /* Attach subchannel private data. */
1302 sch->private = cio_get_console_priv();
1303 memset(sch->private, 0, sizeof(struct io_subchannel_private));
1304 /* Initialize the ccw_device structure. */
1305 cdev->dev.parent= &sch->dev;
1306 rc = io_subchannel_recog(cdev, sch);
1310 /* Now wait for the async. recognition to come to an end. */
1311 spin_lock_irq(cdev->ccwlock);
1312 while (!dev_fsm_final_state(cdev))
1315 if (cdev->private->state != DEV_STATE_OFFLINE)
1317 ccw_device_online(cdev);
1318 while (!dev_fsm_final_state(cdev))
1320 if (cdev->private->state != DEV_STATE_ONLINE)
1324 spin_unlock_irq(cdev->ccwlock);
1329 ccw_device_probe_console(void)
1331 struct subchannel *sch;
1334 if (xchg(&console_cdev_in_use, 1) != 0)
1335 return ERR_PTR(-EBUSY);
1336 sch = cio_probe_console();
1338 console_cdev_in_use = 0;
1339 return (void *) sch;
1341 memset(&console_cdev, 0, sizeof(struct ccw_device));
1342 memset(&console_private, 0, sizeof(struct ccw_device_private));
1343 console_cdev.private = &console_private;
1344 console_private.cdev = &console_cdev;
1345 ret = ccw_device_console_enable(&console_cdev, sch);
1347 cio_release_console();
1348 console_cdev_in_use = 0;
1349 return ERR_PTR(ret);
1351 console_cdev.online = 1;
1352 return &console_cdev;
1357 * get ccw_device matching the busid, but only if owned by cdrv
1360 __ccwdev_check_busid(struct device *dev, void *id)
1366 return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1371 * get_ccwdev_by_busid() - obtain device from a bus id
1372 * @cdrv: driver the device is owned by
1373 * @bus_id: bus id of the device to be searched
1375 * This function searches all devices owned by @cdrv for a device with a bus
1376 * id matching @bus_id.
1378 * If a match is found, its reference count of the found device is increased
1379 * and it is returned; else %NULL is returned.
1381 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1385 struct device_driver *drv;
1387 drv = get_driver(&cdrv->driver);
1391 dev = driver_find_device(drv, NULL, (void *)bus_id,
1392 __ccwdev_check_busid);
1395 return dev ? to_ccwdev(dev) : NULL;
1398 /************************** device driver handling ************************/
1400 /* This is the implementation of the ccw_driver class. The probe, remove
1401 * and release methods are initially very similar to the device_driver
1402 * implementations, with the difference that they have ccw_device
1405 * A ccw driver also contains the information that is needed for
1409 ccw_device_probe (struct device *dev)
1411 struct ccw_device *cdev = to_ccwdev(dev);
1412 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1415 cdev->drv = cdrv; /* to let the driver call _set_online */
1417 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1428 ccw_device_remove (struct device *dev)
1430 struct ccw_device *cdev = to_ccwdev(dev);
1431 struct ccw_driver *cdrv = cdev->drv;
1438 spin_lock_irq(cdev->ccwlock);
1439 ret = ccw_device_offline(cdev);
1440 spin_unlock_irq(cdev->ccwlock);
1442 wait_event(cdev->private->wait_q,
1443 dev_fsm_final_state(cdev));
1445 //FIXME: we can't fail!
1446 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1447 "device 0.%x.%04x\n",
1448 ret, cdev->private->dev_id.ssid,
1449 cdev->private->dev_id.devno);
1451 ccw_device_set_timeout(cdev, 0);
1456 static void ccw_device_shutdown(struct device *dev)
1458 struct ccw_device *cdev;
1460 cdev = to_ccwdev(dev);
1461 if (cdev->drv && cdev->drv->shutdown)
1462 cdev->drv->shutdown(cdev);
1466 struct bus_type ccw_bus_type = {
1468 .match = ccw_bus_match,
1469 .uevent = ccw_uevent,
1470 .probe = ccw_device_probe,
1471 .remove = ccw_device_remove,
1472 .shutdown = ccw_device_shutdown,
1476 * ccw_driver_register() - register a ccw driver
1477 * @cdriver: driver to be registered
1479 * This function is mainly a wrapper around driver_register().
1481 * %0 on success and a negative error value on failure.
1483 int ccw_driver_register(struct ccw_driver *cdriver)
1485 struct device_driver *drv = &cdriver->driver;
1487 drv->bus = &ccw_bus_type;
1488 drv->name = cdriver->name;
1489 drv->owner = cdriver->owner;
1491 return driver_register(drv);
1495 * ccw_driver_unregister() - deregister a ccw driver
1496 * @cdriver: driver to be deregistered
1498 * This function is mainly a wrapper around driver_unregister().
1500 void ccw_driver_unregister(struct ccw_driver *cdriver)
1502 driver_unregister(&cdriver->driver);
1505 /* Helper func for qdio. */
1506 struct subchannel_id
1507 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1509 struct subchannel *sch;
1511 sch = to_subchannel(cdev->dev.parent);
1515 static int recovery_check(struct device *dev, void *data)
1517 struct ccw_device *cdev = to_ccwdev(dev);
1520 spin_lock_irq(cdev->ccwlock);
1521 switch (cdev->private->state) {
1522 case DEV_STATE_DISCONNECTED:
1523 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1524 cdev->private->dev_id.ssid,
1525 cdev->private->dev_id.devno);
1526 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1529 case DEV_STATE_DISCONNECTED_SENSE_ID:
1533 spin_unlock_irq(cdev->ccwlock);
1538 static void recovery_func(unsigned long data)
1542 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1544 spin_lock_irq(&recovery_lock);
1545 if (!timer_pending(&recovery_timer)) {
1546 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1548 mod_timer(&recovery_timer, jiffies +
1549 recovery_delay[recovery_phase] * HZ);
1551 spin_unlock_irq(&recovery_lock);
1553 CIO_MSG_EVENT(2, "recovery: end\n");
1556 void ccw_device_schedule_recovery(void)
1558 unsigned long flags;
1560 CIO_MSG_EVENT(2, "recovery: schedule\n");
1561 spin_lock_irqsave(&recovery_lock, flags);
1562 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1564 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1566 spin_unlock_irqrestore(&recovery_lock, flags);
1569 MODULE_LICENSE("GPL");
1570 EXPORT_SYMBOL(ccw_device_set_online);
1571 EXPORT_SYMBOL(ccw_device_set_offline);
1572 EXPORT_SYMBOL(ccw_driver_register);
1573 EXPORT_SYMBOL(ccw_driver_unregister);
1574 EXPORT_SYMBOL(get_ccwdev_by_busid);
1575 EXPORT_SYMBOL(ccw_bus_type);
1576 EXPORT_SYMBOL(ccw_device_work);
1577 EXPORT_SYMBOL(ccw_device_notify_work);
1578 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);