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>
21 #include <asm/ccwdev.h>
23 #include <asm/param.h> /* HZ */
26 #include "cio_debug.h"
31 /******************* bus type handling ***********************/
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. */
38 ccw_bus_match (struct device * dev, struct device_driver * drv)
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;
47 found = ccw_device_id_match(ids, &cdev->id);
51 cdev->id.driver_info = found->driver_info;
56 /* Store modalias string delimited by prefix/suffix string into buffer with
57 * specified size. Return length of resulting string (excluding trailing '\0')
58 * even if string doesn't fit buffer (snprintf semantics). */
59 static int snprint_alias(char *buf, size_t size,
60 struct ccw_device_id *id, const char *suffix)
64 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
70 if (id->dev_type != 0)
71 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
72 id->dev_model, suffix);
74 len += snprintf(buf, size, "dtdm%s", suffix);
79 /* Set up environment variables for ccw device uevent. Return 0 on success,
80 * non-zero otherwise. */
81 static int ccw_uevent(struct device *dev, char **envp, int num_envp,
82 char *buffer, int buffer_size)
84 struct ccw_device *cdev = to_ccwdev(dev);
85 struct ccw_device_id *id = &(cdev->id);
89 char modalias_buf[30];
92 ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
93 "CU_TYPE=%04X", id->cu_type);
98 ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
99 "CU_MODEL=%02X", id->cu_model);
103 /* The next two can be zero, that's ok for us */
105 ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
106 "DEV_TYPE=%04X", id->dev_type);
111 ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
112 "DEV_MODEL=%02X", id->dev_model);
117 snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
118 ret = add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &len,
119 "MODALIAS=%s", modalias_buf);
126 struct bus_type ccw_bus_type;
128 static int io_subchannel_probe (struct subchannel *);
129 static int io_subchannel_remove (struct subchannel *);
130 static int io_subchannel_notify(struct device *, int);
131 static void io_subchannel_verify(struct device *);
132 static void io_subchannel_ioterm(struct device *);
133 static void io_subchannel_shutdown(struct subchannel *);
135 static struct css_driver io_subchannel_driver = {
136 .subchannel_type = SUBCHANNEL_TYPE_IO,
138 .name = "io_subchannel",
139 .bus = &css_bus_type,
141 .irq = io_subchannel_irq,
142 .notify = io_subchannel_notify,
143 .verify = io_subchannel_verify,
144 .termination = io_subchannel_ioterm,
145 .probe = io_subchannel_probe,
146 .remove = io_subchannel_remove,
147 .shutdown = io_subchannel_shutdown,
150 struct workqueue_struct *ccw_device_work;
151 struct workqueue_struct *ccw_device_notify_work;
152 wait_queue_head_t ccw_device_init_wq;
153 atomic_t ccw_device_init_count;
156 init_ccw_bus_type (void)
160 init_waitqueue_head(&ccw_device_init_wq);
161 atomic_set(&ccw_device_init_count, 0);
163 ccw_device_work = create_singlethread_workqueue("cio");
164 if (!ccw_device_work)
165 return -ENOMEM; /* FIXME: better errno ? */
166 ccw_device_notify_work = create_singlethread_workqueue("cio_notify");
167 if (!ccw_device_notify_work) {
168 ret = -ENOMEM; /* FIXME: better errno ? */
171 slow_path_wq = create_singlethread_workqueue("kslowcrw");
173 ret = -ENOMEM; /* FIXME: better errno ? */
176 if ((ret = bus_register (&ccw_bus_type)))
179 if ((ret = driver_register(&io_subchannel_driver.drv)))
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 driver_unregister(&io_subchannel_driver.drv);
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_LIST_HEAD(&cdev->private->kick_work.entry);
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->dev.driver_data = 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 other_sch->dev.driver_data = 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->dev.driver_data = 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->dev.driver_data = 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->dev.driver_data = 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);
972 ccw_device_call_sch_unregister(struct work_struct *work)
974 struct ccw_device_private *priv;
975 struct ccw_device *cdev;
976 struct subchannel *sch;
978 priv = container_of(work, struct ccw_device_private, kick_work);
980 sch = to_subchannel(cdev->dev.parent);
981 css_sch_device_unregister(sch);
982 /* Reset intparm to zeroes. */
983 sch->schib.pmcw.intparm = 0;
985 put_device(&cdev->dev);
986 put_device(&sch->dev);
990 * subchannel recognition done. Called from the state machine.
993 io_subchannel_recog_done(struct ccw_device *cdev)
995 struct subchannel *sch;
997 if (css_init_done == 0) {
998 cdev->private->flags.recog_done = 1;
1001 switch (cdev->private->state) {
1002 case DEV_STATE_NOT_OPER:
1003 cdev->private->flags.recog_done = 1;
1004 /* Remove device found not operational. */
1005 if (!get_device(&cdev->dev))
1007 sch = to_subchannel(cdev->dev.parent);
1008 PREPARE_WORK(&cdev->private->kick_work,
1009 ccw_device_call_sch_unregister);
1010 queue_work(slow_path_wq, &cdev->private->kick_work);
1011 if (atomic_dec_and_test(&ccw_device_init_count))
1012 wake_up(&ccw_device_init_wq);
1014 case DEV_STATE_BOXED:
1015 /* Device did not respond in time. */
1016 case DEV_STATE_OFFLINE:
1018 * We can't register the device in interrupt context so
1019 * we schedule a work item.
1021 if (!get_device(&cdev->dev))
1023 PREPARE_WORK(&cdev->private->kick_work,
1024 io_subchannel_register);
1025 queue_work(slow_path_wq, &cdev->private->kick_work);
1031 io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
1034 struct ccw_device_private *priv;
1036 sch->dev.driver_data = cdev;
1037 sch->driver = &io_subchannel_driver;
1038 cdev->ccwlock = sch->lock;
1040 /* Init private data. */
1041 priv = cdev->private;
1042 priv->dev_id.devno = sch->schib.pmcw.dev;
1043 priv->dev_id.ssid = sch->schid.ssid;
1044 priv->schid = sch->schid;
1045 priv->state = DEV_STATE_NOT_OPER;
1046 INIT_LIST_HEAD(&priv->cmb_list);
1047 init_waitqueue_head(&priv->wait_q);
1048 init_timer(&priv->timer);
1050 /* Set an initial name for the device. */
1051 snprintf (cdev->dev.bus_id, BUS_ID_SIZE, "0.%x.%04x",
1052 sch->schid.ssid, sch->schib.pmcw.dev);
1054 /* Increase counter of devices currently in recognition. */
1055 atomic_inc(&ccw_device_init_count);
1057 /* Start async. device sensing. */
1058 spin_lock_irq(sch->lock);
1059 rc = ccw_device_recognition(cdev);
1060 spin_unlock_irq(sch->lock);
1062 if (atomic_dec_and_test(&ccw_device_init_count))
1063 wake_up(&ccw_device_init_wq);
1068 static void ccw_device_move_to_sch(struct work_struct *work)
1070 struct ccw_device_private *priv;
1072 struct subchannel *sch;
1073 struct ccw_device *cdev;
1074 struct subchannel *former_parent;
1076 priv = container_of(work, struct ccw_device_private, kick_work);
1079 former_parent = ccw_device_is_orphan(cdev) ?
1080 NULL : to_subchannel(get_device(cdev->dev.parent));
1081 mutex_lock(&sch->reg_mutex);
1082 /* Try to move the ccw device to its new subchannel. */
1083 rc = device_move(&cdev->dev, &sch->dev);
1084 mutex_unlock(&sch->reg_mutex);
1086 CIO_MSG_EVENT(2, "Moving device 0.%x.%04x to subchannel "
1087 "0.%x.%04x failed (ret=%d)!\n",
1088 cdev->private->dev_id.ssid,
1089 cdev->private->dev_id.devno, sch->schid.ssid,
1090 sch->schid.sch_no, rc);
1091 css_sch_device_unregister(sch);
1094 if (former_parent) {
1095 spin_lock_irq(former_parent->lock);
1096 former_parent->dev.driver_data = NULL;
1097 spin_unlock_irq(former_parent->lock);
1098 css_sch_device_unregister(former_parent);
1099 /* Reset intparm to zeroes. */
1100 former_parent->schib.pmcw.intparm = 0;
1101 cio_modify(former_parent);
1103 sch_attach_device(sch, cdev);
1106 put_device(&former_parent->dev);
1107 put_device(&cdev->dev);
1111 io_subchannel_probe (struct subchannel *sch)
1113 struct ccw_device *cdev;
1115 unsigned long flags;
1116 struct ccw_dev_id dev_id;
1118 if (sch->dev.driver_data) {
1120 * This subchannel already has an associated ccw_device.
1121 * Register it and exit. This happens for all early
1122 * device, e.g. the console.
1124 cdev = sch->dev.driver_data;
1125 device_initialize(&cdev->dev);
1126 ccw_device_register(cdev);
1128 * Check if the device is already online. If it is
1129 * the reference count needs to be corrected
1130 * (see ccw_device_online and css_init_done for the
1133 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1134 cdev->private->state != DEV_STATE_OFFLINE &&
1135 cdev->private->state != DEV_STATE_BOXED)
1136 get_device(&cdev->dev);
1140 * First check if a fitting device may be found amongst the
1141 * disconnected devices or in the orphanage.
1143 dev_id.devno = sch->schib.pmcw.dev;
1144 dev_id.ssid = sch->schid.ssid;
1145 cdev = get_disc_ccwdev_by_dev_id(&dev_id, NULL);
1147 cdev = get_orphaned_ccwdev_by_dev_id(to_css(sch->dev.parent),
1151 * Schedule moving the device until when we have a registered
1152 * subchannel to move to and succeed the probe. We can
1153 * unregister later again, when the probe is through.
1155 cdev->private->sch = sch;
1156 PREPARE_WORK(&cdev->private->kick_work,
1157 ccw_device_move_to_sch);
1158 queue_work(slow_path_wq, &cdev->private->kick_work);
1161 cdev = io_subchannel_create_ccwdev(sch);
1163 return PTR_ERR(cdev);
1165 rc = io_subchannel_recog(cdev, sch);
1167 spin_lock_irqsave(sch->lock, flags);
1168 sch->dev.driver_data = NULL;
1169 spin_unlock_irqrestore(sch->lock, flags);
1170 if (cdev->dev.release)
1171 cdev->dev.release(&cdev->dev);
1178 io_subchannel_remove (struct subchannel *sch)
1180 struct ccw_device *cdev;
1181 unsigned long flags;
1183 if (!sch->dev.driver_data)
1185 cdev = sch->dev.driver_data;
1186 /* Set ccw device to not operational and drop reference. */
1187 spin_lock_irqsave(cdev->ccwlock, flags);
1188 sch->dev.driver_data = NULL;
1189 cdev->private->state = DEV_STATE_NOT_OPER;
1190 spin_unlock_irqrestore(cdev->ccwlock, flags);
1191 ccw_device_unregister(cdev);
1192 put_device(&cdev->dev);
1197 io_subchannel_notify(struct device *dev, int event)
1199 struct ccw_device *cdev;
1201 cdev = dev->driver_data;
1208 return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
1212 io_subchannel_verify(struct device *dev)
1214 struct ccw_device *cdev;
1216 cdev = dev->driver_data;
1218 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1222 io_subchannel_ioterm(struct device *dev)
1224 struct ccw_device *cdev;
1226 cdev = dev->driver_data;
1229 /* Internal I/O will be retried by the interrupt handler. */
1230 if (cdev->private->flags.intretry)
1232 cdev->private->state = DEV_STATE_CLEAR_VERIFY;
1234 cdev->handler(cdev, cdev->private->intparm,
1239 io_subchannel_shutdown(struct subchannel *sch)
1241 struct ccw_device *cdev;
1244 cdev = sch->dev.driver_data;
1246 if (cio_is_console(sch->schid))
1248 if (!sch->schib.pmcw.ena)
1249 /* Nothing to do. */
1251 ret = cio_disable_subchannel(sch);
1253 /* Subchannel is disabled, we're done. */
1255 cdev->private->state = DEV_STATE_QUIESCE;
1257 cdev->handler(cdev, cdev->private->intparm,
1259 ret = ccw_device_cancel_halt_clear(cdev);
1260 if (ret == -EBUSY) {
1261 ccw_device_set_timeout(cdev, HZ/10);
1262 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1264 cio_disable_subchannel(sch);
1267 #ifdef CONFIG_CCW_CONSOLE
1268 static struct ccw_device console_cdev;
1269 static struct ccw_device_private console_private;
1270 static int console_cdev_in_use;
1272 static DEFINE_SPINLOCK(ccw_console_lock);
1274 spinlock_t * cio_get_console_lock(void)
1276 return &ccw_console_lock;
1280 ccw_device_console_enable (struct ccw_device *cdev, struct subchannel *sch)
1284 /* Initialize the ccw_device structure. */
1285 cdev->dev.parent= &sch->dev;
1286 rc = io_subchannel_recog(cdev, sch);
1290 /* Now wait for the async. recognition to come to an end. */
1291 spin_lock_irq(cdev->ccwlock);
1292 while (!dev_fsm_final_state(cdev))
1295 if (cdev->private->state != DEV_STATE_OFFLINE)
1297 ccw_device_online(cdev);
1298 while (!dev_fsm_final_state(cdev))
1300 if (cdev->private->state != DEV_STATE_ONLINE)
1304 spin_unlock_irq(cdev->ccwlock);
1309 ccw_device_probe_console(void)
1311 struct subchannel *sch;
1314 if (xchg(&console_cdev_in_use, 1) != 0)
1315 return ERR_PTR(-EBUSY);
1316 sch = cio_probe_console();
1318 console_cdev_in_use = 0;
1319 return (void *) sch;
1321 memset(&console_cdev, 0, sizeof(struct ccw_device));
1322 memset(&console_private, 0, sizeof(struct ccw_device_private));
1323 console_cdev.private = &console_private;
1324 console_private.cdev = &console_cdev;
1325 ret = ccw_device_console_enable(&console_cdev, sch);
1327 cio_release_console();
1328 console_cdev_in_use = 0;
1329 return ERR_PTR(ret);
1331 console_cdev.online = 1;
1332 return &console_cdev;
1337 * get ccw_device matching the busid, but only if owned by cdrv
1340 __ccwdev_check_busid(struct device *dev, void *id)
1346 return (strncmp(bus_id, dev->bus_id, BUS_ID_SIZE) == 0);
1351 * get_ccwdev_by_busid() - obtain device from a bus id
1352 * @cdrv: driver the device is owned by
1353 * @bus_id: bus id of the device to be searched
1355 * This function searches all devices owned by @cdrv for a device with a bus
1356 * id matching @bus_id.
1358 * If a match is found, its reference count of the found device is increased
1359 * and it is returned; else %NULL is returned.
1361 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1365 struct device_driver *drv;
1367 drv = get_driver(&cdrv->driver);
1371 dev = driver_find_device(drv, NULL, (void *)bus_id,
1372 __ccwdev_check_busid);
1375 return dev ? to_ccwdev(dev) : NULL;
1378 /************************** device driver handling ************************/
1380 /* This is the implementation of the ccw_driver class. The probe, remove
1381 * and release methods are initially very similar to the device_driver
1382 * implementations, with the difference that they have ccw_device
1385 * A ccw driver also contains the information that is needed for
1389 ccw_device_probe (struct device *dev)
1391 struct ccw_device *cdev = to_ccwdev(dev);
1392 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1395 cdev->drv = cdrv; /* to let the driver call _set_online */
1397 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1408 ccw_device_remove (struct device *dev)
1410 struct ccw_device *cdev = to_ccwdev(dev);
1411 struct ccw_driver *cdrv = cdev->drv;
1418 spin_lock_irq(cdev->ccwlock);
1419 ret = ccw_device_offline(cdev);
1420 spin_unlock_irq(cdev->ccwlock);
1422 wait_event(cdev->private->wait_q,
1423 dev_fsm_final_state(cdev));
1425 //FIXME: we can't fail!
1426 CIO_MSG_EVENT(2, "ccw_device_offline returned %d, "
1427 "device 0.%x.%04x\n",
1428 ret, cdev->private->dev_id.ssid,
1429 cdev->private->dev_id.devno);
1431 ccw_device_set_timeout(cdev, 0);
1436 struct bus_type ccw_bus_type = {
1438 .match = ccw_bus_match,
1439 .uevent = ccw_uevent,
1440 .probe = ccw_device_probe,
1441 .remove = ccw_device_remove,
1445 * ccw_driver_register() - register a ccw driver
1446 * @cdriver: driver to be registered
1448 * This function is mainly a wrapper around driver_register().
1450 * %0 on success and a negative error value on failure.
1452 int ccw_driver_register(struct ccw_driver *cdriver)
1454 struct device_driver *drv = &cdriver->driver;
1456 drv->bus = &ccw_bus_type;
1457 drv->name = cdriver->name;
1459 return driver_register(drv);
1463 * ccw_driver_unregister() - deregister a ccw driver
1464 * @cdriver: driver to be deregistered
1466 * This function is mainly a wrapper around driver_unregister().
1468 void ccw_driver_unregister(struct ccw_driver *cdriver)
1470 driver_unregister(&cdriver->driver);
1473 /* Helper func for qdio. */
1474 struct subchannel_id
1475 ccw_device_get_subchannel_id(struct ccw_device *cdev)
1477 struct subchannel *sch;
1479 sch = to_subchannel(cdev->dev.parent);
1483 MODULE_LICENSE("GPL");
1484 EXPORT_SYMBOL(ccw_device_set_online);
1485 EXPORT_SYMBOL(ccw_device_set_offline);
1486 EXPORT_SYMBOL(ccw_driver_register);
1487 EXPORT_SYMBOL(ccw_driver_unregister);
1488 EXPORT_SYMBOL(get_ccwdev_by_busid);
1489 EXPORT_SYMBOL(ccw_bus_type);
1490 EXPORT_SYMBOL(ccw_device_work);
1491 EXPORT_SYMBOL(ccw_device_notify_work);
1492 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);