2 * bus driver for ccw devices
4 * Copyright IBM Corp. 2002, 2008
5 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
6 * Cornelia Huck (cornelia.huck@de.ibm.com)
7 * Martin Schwidefsky (schwidefsky@de.ibm.com)
10 #define KMSG_COMPONENT "cio"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/spinlock.h>
16 #include <linux/errno.h>
17 #include <linux/err.h>
18 #include <linux/slab.h>
19 #include <linux/list.h>
20 #include <linux/device.h>
21 #include <linux/workqueue.h>
22 #include <linux/delay.h>
23 #include <linux/timer.h>
24 #include <linux/kernel_stat.h>
26 #include <asm/ccwdev.h>
28 #include <asm/param.h> /* HZ */
34 #include "cio_debug.h"
39 #include "blacklist.h"
42 static struct timer_list recovery_timer;
43 static DEFINE_SPINLOCK(recovery_lock);
44 static int recovery_phase;
45 static const unsigned long recovery_delay[] = { 3, 30, 300 };
47 static atomic_t ccw_device_init_count = ATOMIC_INIT(0);
48 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq);
49 static struct bus_type ccw_bus_type;
51 /******************* bus type handling ***********************/
53 /* The Linux driver model distinguishes between a bus type and
54 * the bus itself. Of course we only have one channel
55 * subsystem driver and one channel system per machine, but
56 * we still use the abstraction. T.R. says it's a good idea. */
58 ccw_bus_match (struct device * dev, struct device_driver * drv)
60 struct ccw_device *cdev = to_ccwdev(dev);
61 struct ccw_driver *cdrv = to_ccwdrv(drv);
62 const struct ccw_device_id *ids = cdrv->ids, *found;
67 found = ccw_device_id_match(ids, &cdev->id);
71 cdev->id.driver_info = found->driver_info;
76 /* Store modalias string delimited by prefix/suffix string into buffer with
77 * specified size. Return length of resulting string (excluding trailing '\0')
78 * even if string doesn't fit buffer (snprintf semantics). */
79 static int snprint_alias(char *buf, size_t size,
80 struct ccw_device_id *id, const char *suffix)
84 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
90 if (id->dev_type != 0)
91 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
92 id->dev_model, suffix);
94 len += snprintf(buf, size, "dtdm%s", suffix);
99 /* Set up environment variables for ccw device uevent. Return 0 on success,
100 * non-zero otherwise. */
101 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
103 struct ccw_device *cdev = to_ccwdev(dev);
104 struct ccw_device_id *id = &(cdev->id);
106 char modalias_buf[30];
109 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
114 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
118 /* The next two can be zero, that's ok for us */
120 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
125 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
130 snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
131 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
135 static void io_subchannel_irq(struct subchannel *);
136 static int io_subchannel_probe(struct subchannel *);
137 static int io_subchannel_remove(struct subchannel *);
138 static void io_subchannel_shutdown(struct subchannel *);
139 static int io_subchannel_sch_event(struct subchannel *, int);
140 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
142 static void recovery_func(unsigned long data);
144 static struct css_device_id io_subchannel_ids[] = {
145 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
146 { /* end of list */ },
148 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
150 static int io_subchannel_prepare(struct subchannel *sch)
152 struct ccw_device *cdev;
154 * Don't allow suspend while a ccw device registration
155 * is still outstanding.
157 cdev = sch_get_cdev(sch);
158 if (cdev && !device_is_registered(&cdev->dev))
163 static int io_subchannel_settle(void)
167 ret = wait_event_interruptible(ccw_device_init_wq,
168 atomic_read(&ccw_device_init_count) == 0);
171 flush_workqueue(cio_work_q);
175 static struct css_driver io_subchannel_driver = {
177 .owner = THIS_MODULE,
178 .name = "io_subchannel",
180 .subchannel_type = io_subchannel_ids,
181 .irq = io_subchannel_irq,
182 .sch_event = io_subchannel_sch_event,
183 .chp_event = io_subchannel_chp_event,
184 .probe = io_subchannel_probe,
185 .remove = io_subchannel_remove,
186 .shutdown = io_subchannel_shutdown,
187 .prepare = io_subchannel_prepare,
188 .settle = io_subchannel_settle,
191 int __init io_subchannel_init(void)
195 setup_timer(&recovery_timer, recovery_func, 0);
196 ret = bus_register(&ccw_bus_type);
199 ret = css_driver_register(&io_subchannel_driver);
201 bus_unregister(&ccw_bus_type);
207 /************************ device handling **************************/
210 * A ccw_device has some interfaces in sysfs in addition to the
212 * The following entries are designed to export the information which
213 * resided in 2.4 in /proc/subchannels. Subchannel and device number
214 * are obvious, so they don't have an entry :)
215 * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
218 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
220 struct subchannel *sch = to_subchannel(dev);
221 struct chsc_ssd_info *ssd = &sch->ssd_info;
226 for (chp = 0; chp < 8; chp++) {
228 if (ssd->path_mask & mask)
229 ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
231 ret += sprintf(buf + ret, "00 ");
233 ret += sprintf (buf+ret, "\n");
234 return min((ssize_t)PAGE_SIZE, ret);
238 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
240 struct subchannel *sch = to_subchannel(dev);
241 struct pmcw *pmcw = &sch->schib.pmcw;
243 return sprintf (buf, "%02x %02x %02x\n",
244 pmcw->pim, pmcw->pam, pmcw->pom);
248 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
250 struct ccw_device *cdev = to_ccwdev(dev);
251 struct ccw_device_id *id = &(cdev->id);
253 if (id->dev_type != 0)
254 return sprintf(buf, "%04x/%02x\n",
255 id->dev_type, id->dev_model);
257 return sprintf(buf, "n/a\n");
261 cutype_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 return sprintf(buf, "%04x/%02x\n",
267 id->cu_type, id->cu_model);
271 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
273 struct ccw_device *cdev = to_ccwdev(dev);
274 struct ccw_device_id *id = &(cdev->id);
277 len = snprint_alias(buf, PAGE_SIZE, id, "\n");
279 return len > PAGE_SIZE ? PAGE_SIZE : len;
283 online_show (struct device *dev, struct device_attribute *attr, char *buf)
285 struct ccw_device *cdev = to_ccwdev(dev);
287 return sprintf(buf, cdev->online ? "1\n" : "0\n");
290 int ccw_device_is_orphan(struct ccw_device *cdev)
292 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
295 static void ccw_device_unregister(struct ccw_device *cdev)
297 if (device_is_registered(&cdev->dev)) {
298 /* Undo device_add(). */
299 device_del(&cdev->dev);
301 if (cdev->private->flags.initialized) {
302 cdev->private->flags.initialized = 0;
303 /* Release reference from device_initialize(). */
304 put_device(&cdev->dev);
308 static void io_subchannel_quiesce(struct subchannel *);
311 * ccw_device_set_offline() - disable a ccw device for I/O
312 * @cdev: target ccw device
314 * This function calls the driver's set_offline() function for @cdev, if
315 * given, and then disables @cdev.
317 * %0 on success and a negative error value on failure.
319 * enabled, ccw device lock not held
321 int ccw_device_set_offline(struct ccw_device *cdev)
323 struct subchannel *sch;
328 if (!cdev->online || !cdev->drv)
331 if (cdev->drv->set_offline) {
332 ret = cdev->drv->set_offline(cdev);
336 spin_lock_irq(cdev->ccwlock);
337 sch = to_subchannel(cdev->dev.parent);
339 /* Wait until a final state or DISCONNECTED is reached */
340 while (!dev_fsm_final_state(cdev) &&
341 cdev->private->state != DEV_STATE_DISCONNECTED) {
342 spin_unlock_irq(cdev->ccwlock);
343 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
344 cdev->private->state == DEV_STATE_DISCONNECTED));
345 spin_lock_irq(cdev->ccwlock);
348 ret = ccw_device_offline(cdev);
351 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
352 "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
353 cdev->private->dev_id.devno);
356 state = cdev->private->state;
357 spin_unlock_irq(cdev->ccwlock);
358 io_subchannel_quiesce(sch);
359 spin_lock_irq(cdev->ccwlock);
360 cdev->private->state = state;
361 } while (ret == -EBUSY);
362 spin_unlock_irq(cdev->ccwlock);
363 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
364 cdev->private->state == DEV_STATE_DISCONNECTED));
365 /* Inform the user if set offline failed. */
366 if (cdev->private->state == DEV_STATE_BOXED) {
367 pr_warn("%s: The device entered boxed state while being set offline\n",
368 dev_name(&cdev->dev));
369 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
370 pr_warn("%s: The device stopped operating while being set offline\n",
371 dev_name(&cdev->dev));
373 /* Give up reference from ccw_device_set_online(). */
374 put_device(&cdev->dev);
378 cdev->private->state = DEV_STATE_OFFLINE;
379 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
380 spin_unlock_irq(cdev->ccwlock);
381 /* Give up reference from ccw_device_set_online(). */
382 put_device(&cdev->dev);
387 * ccw_device_set_online() - enable a ccw device for I/O
388 * @cdev: target ccw device
390 * This function first enables @cdev and then calls the driver's set_online()
391 * function for @cdev, if given. If set_online() returns an error, @cdev is
394 * %0 on success and a negative error value on failure.
396 * enabled, ccw device lock not held
398 int ccw_device_set_online(struct ccw_device *cdev)
405 if (cdev->online || !cdev->drv)
407 /* Hold on to an extra reference while device is online. */
408 if (!get_device(&cdev->dev))
411 spin_lock_irq(cdev->ccwlock);
412 ret = ccw_device_online(cdev);
413 spin_unlock_irq(cdev->ccwlock);
415 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
417 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
418 "device 0.%x.%04x\n",
419 ret, cdev->private->dev_id.ssid,
420 cdev->private->dev_id.devno);
421 /* Give up online reference since onlining failed. */
422 put_device(&cdev->dev);
425 spin_lock_irq(cdev->ccwlock);
426 /* Check if online processing was successful */
427 if ((cdev->private->state != DEV_STATE_ONLINE) &&
428 (cdev->private->state != DEV_STATE_W4SENSE)) {
429 spin_unlock_irq(cdev->ccwlock);
430 /* Inform the user that set online failed. */
431 if (cdev->private->state == DEV_STATE_BOXED) {
432 pr_warn("%s: Setting the device online failed because it is boxed\n",
433 dev_name(&cdev->dev));
434 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
435 pr_warn("%s: Setting the device online failed because it is not operational\n",
436 dev_name(&cdev->dev));
438 /* Give up online reference since onlining failed. */
439 put_device(&cdev->dev);
442 spin_unlock_irq(cdev->ccwlock);
443 if (cdev->drv->set_online)
444 ret = cdev->drv->set_online(cdev);
448 spin_lock_irq(cdev->ccwlock);
450 spin_unlock_irq(cdev->ccwlock);
454 spin_lock_irq(cdev->ccwlock);
455 /* Wait until a final state or DISCONNECTED is reached */
456 while (!dev_fsm_final_state(cdev) &&
457 cdev->private->state != DEV_STATE_DISCONNECTED) {
458 spin_unlock_irq(cdev->ccwlock);
459 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
460 cdev->private->state == DEV_STATE_DISCONNECTED));
461 spin_lock_irq(cdev->ccwlock);
463 ret2 = ccw_device_offline(cdev);
466 spin_unlock_irq(cdev->ccwlock);
467 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
468 cdev->private->state == DEV_STATE_DISCONNECTED));
469 /* Give up online reference since onlining failed. */
470 put_device(&cdev->dev);
474 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
475 "device 0.%x.%04x\n",
476 ret2, cdev->private->dev_id.ssid,
477 cdev->private->dev_id.devno);
478 cdev->private->state = DEV_STATE_OFFLINE;
479 spin_unlock_irq(cdev->ccwlock);
480 /* Give up online reference since onlining failed. */
481 put_device(&cdev->dev);
485 static int online_store_handle_offline(struct ccw_device *cdev)
487 if (cdev->private->state == DEV_STATE_DISCONNECTED) {
488 spin_lock_irq(cdev->ccwlock);
489 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
490 spin_unlock_irq(cdev->ccwlock);
493 if (cdev->drv && cdev->drv->set_offline)
494 return ccw_device_set_offline(cdev);
498 static int online_store_recog_and_online(struct ccw_device *cdev)
500 /* Do device recognition, if needed. */
501 if (cdev->private->state == DEV_STATE_BOXED) {
502 spin_lock_irq(cdev->ccwlock);
503 ccw_device_recognition(cdev);
504 spin_unlock_irq(cdev->ccwlock);
505 wait_event(cdev->private->wait_q,
506 cdev->private->flags.recog_done);
507 if (cdev->private->state != DEV_STATE_OFFLINE)
508 /* recognition failed */
511 if (cdev->drv && cdev->drv->set_online)
512 return ccw_device_set_online(cdev);
516 static int online_store_handle_online(struct ccw_device *cdev, int force)
520 ret = online_store_recog_and_online(cdev);
523 if (force && cdev->private->state == DEV_STATE_BOXED) {
524 ret = ccw_device_stlck(cdev);
527 if (cdev->id.cu_type == 0)
528 cdev->private->state = DEV_STATE_NOT_OPER;
529 ret = online_store_recog_and_online(cdev);
536 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
537 const char *buf, size_t count)
539 struct ccw_device *cdev = to_ccwdev(dev);
543 /* Prevent conflict between multiple on-/offline processing requests. */
544 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
546 /* Prevent conflict between internal I/Os and on-/offline processing. */
547 if (!dev_fsm_final_state(cdev) &&
548 cdev->private->state != DEV_STATE_DISCONNECTED) {
552 /* Prevent conflict between pending work and on-/offline processing.*/
553 if (work_pending(&cdev->private->todo_work)) {
557 if (!strncmp(buf, "force\n", count)) {
563 ret = kstrtoul(buf, 16, &i);
571 ret = online_store_handle_offline(cdev);
574 ret = online_store_handle_online(cdev, force);
582 atomic_set(&cdev->private->onoff, 0);
583 return (ret < 0) ? ret : count;
587 available_show (struct device *dev, struct device_attribute *attr, char *buf)
589 struct ccw_device *cdev = to_ccwdev(dev);
590 struct subchannel *sch;
592 if (ccw_device_is_orphan(cdev))
593 return sprintf(buf, "no device\n");
594 switch (cdev->private->state) {
595 case DEV_STATE_BOXED:
596 return sprintf(buf, "boxed\n");
597 case DEV_STATE_DISCONNECTED:
598 case DEV_STATE_DISCONNECTED_SENSE_ID:
599 case DEV_STATE_NOT_OPER:
600 sch = to_subchannel(dev->parent);
602 return sprintf(buf, "no path\n");
604 return sprintf(buf, "no device\n");
606 /* All other states considered fine. */
607 return sprintf(buf, "good\n");
612 initiate_logging(struct device *dev, struct device_attribute *attr,
613 const char *buf, size_t count)
615 struct subchannel *sch = to_subchannel(dev);
618 rc = chsc_siosl(sch->schid);
620 pr_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n",
621 sch->schid.ssid, sch->schid.sch_no, rc);
624 pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
625 sch->schid.ssid, sch->schid.sch_no);
629 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
632 struct subchannel *sch = to_subchannel(dev);
634 return sprintf(buf, "%02x\n", sch->vpm);
637 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
638 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
639 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
640 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
641 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
642 static DEVICE_ATTR(online, 0644, online_show, online_store);
643 static DEVICE_ATTR(availability, 0444, available_show, NULL);
644 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
645 static DEVICE_ATTR(vpm, 0444, vpm_show, NULL);
647 static struct attribute *io_subchannel_attrs[] = {
648 &dev_attr_chpids.attr,
649 &dev_attr_pimpampom.attr,
650 &dev_attr_logging.attr,
655 static struct attribute_group io_subchannel_attr_group = {
656 .attrs = io_subchannel_attrs,
659 static struct attribute * ccwdev_attrs[] = {
660 &dev_attr_devtype.attr,
661 &dev_attr_cutype.attr,
662 &dev_attr_modalias.attr,
663 &dev_attr_online.attr,
664 &dev_attr_cmb_enable.attr,
665 &dev_attr_availability.attr,
669 static struct attribute_group ccwdev_attr_group = {
670 .attrs = ccwdev_attrs,
673 static const struct attribute_group *ccwdev_attr_groups[] = {
678 static int ccw_device_add(struct ccw_device *cdev)
680 struct device *dev = &cdev->dev;
682 dev->bus = &ccw_bus_type;
683 return device_add(dev);
686 static int match_dev_id(struct device *dev, void *data)
688 struct ccw_device *cdev = to_ccwdev(dev);
689 struct ccw_dev_id *dev_id = data;
691 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
695 * get_ccwdev_by_dev_id() - obtain device from a ccw device id
696 * @dev_id: id of the device to be searched
698 * This function searches all devices attached to the ccw bus for a device
701 * If a device is found its reference count is increased and returned;
702 * else %NULL is returned.
704 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
708 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
710 return dev ? to_ccwdev(dev) : NULL;
712 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
714 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
718 if (device_is_registered(&cdev->dev)) {
719 device_release_driver(&cdev->dev);
720 ret = device_attach(&cdev->dev);
721 WARN_ON(ret == -ENODEV);
726 ccw_device_release(struct device *dev)
728 struct ccw_device *cdev;
730 cdev = to_ccwdev(dev);
731 /* Release reference of parent subchannel. */
732 put_device(cdev->dev.parent);
733 kfree(cdev->private);
737 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
739 struct ccw_device *cdev;
741 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
743 cdev->private = kzalloc(sizeof(struct ccw_device_private),
744 GFP_KERNEL | GFP_DMA);
749 return ERR_PTR(-ENOMEM);
752 static void ccw_device_todo(struct work_struct *work);
754 static int io_subchannel_initialize_dev(struct subchannel *sch,
755 struct ccw_device *cdev)
757 struct ccw_device_private *priv = cdev->private;
761 priv->int_class = IRQIO_CIO;
762 priv->state = DEV_STATE_NOT_OPER;
763 priv->dev_id.devno = sch->schib.pmcw.dev;
764 priv->dev_id.ssid = sch->schid.ssid;
766 INIT_WORK(&priv->todo_work, ccw_device_todo);
767 INIT_LIST_HEAD(&priv->cmb_list);
768 init_waitqueue_head(&priv->wait_q);
769 init_timer(&priv->timer);
771 atomic_set(&priv->onoff, 0);
772 cdev->ccwlock = sch->lock;
773 cdev->dev.parent = &sch->dev;
774 cdev->dev.release = ccw_device_release;
775 cdev->dev.groups = ccwdev_attr_groups;
776 /* Do first half of device_register. */
777 device_initialize(&cdev->dev);
778 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
779 cdev->private->dev_id.devno);
782 if (!get_device(&sch->dev)) {
786 priv->flags.initialized = 1;
787 spin_lock_irq(sch->lock);
788 sch_set_cdev(sch, cdev);
789 spin_unlock_irq(sch->lock);
793 /* Release reference from device_initialize(). */
794 put_device(&cdev->dev);
798 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
800 struct ccw_device *cdev;
803 cdev = io_subchannel_allocate_dev(sch);
805 ret = io_subchannel_initialize_dev(sch, cdev);
812 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
814 static void sch_create_and_recog_new_device(struct subchannel *sch)
816 struct ccw_device *cdev;
818 /* Need to allocate a new ccw device. */
819 cdev = io_subchannel_create_ccwdev(sch);
821 /* OK, we did everything we could... */
822 css_sch_device_unregister(sch);
825 /* Start recognition for the new ccw device. */
826 io_subchannel_recog(cdev, sch);
830 * Register recognized device.
832 static void io_subchannel_register(struct ccw_device *cdev)
834 struct subchannel *sch;
835 int ret, adjust_init_count = 1;
838 sch = to_subchannel(cdev->dev.parent);
840 * Check if subchannel is still registered. It may have become
841 * unregistered if a machine check hit us after finishing
842 * device recognition but before the register work could be
845 if (!device_is_registered(&sch->dev))
847 css_update_ssd_info(sch);
849 * io_subchannel_register() will also be called after device
850 * recognition has been done for a boxed device (which will already
851 * be registered). We need to reprobe since we may now have sense id
854 if (device_is_registered(&cdev->dev)) {
856 ret = device_reprobe(&cdev->dev);
858 /* We can't do much here. */
859 CIO_MSG_EVENT(0, "device_reprobe() returned"
860 " %d for 0.%x.%04x\n", ret,
861 cdev->private->dev_id.ssid,
862 cdev->private->dev_id.devno);
864 adjust_init_count = 0;
868 * Now we know this subchannel will stay, we can throw
869 * our delayed uevent.
871 if (dev_get_uevent_suppress(&sch->dev)) {
872 dev_set_uevent_suppress(&sch->dev, 0);
873 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
875 /* make it known to the system */
876 ret = ccw_device_add(cdev);
878 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
879 cdev->private->dev_id.ssid,
880 cdev->private->dev_id.devno, ret);
881 spin_lock_irqsave(sch->lock, flags);
882 sch_set_cdev(sch, NULL);
883 spin_unlock_irqrestore(sch->lock, flags);
884 /* Release initial device reference. */
885 put_device(&cdev->dev);
889 cdev->private->flags.recog_done = 1;
890 wake_up(&cdev->private->wait_q);
892 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
893 wake_up(&ccw_device_init_wq);
896 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
898 struct subchannel *sch;
900 /* Get subchannel reference for local processing. */
901 if (!get_device(cdev->dev.parent))
903 sch = to_subchannel(cdev->dev.parent);
904 css_sch_device_unregister(sch);
905 /* Release subchannel reference for local processing. */
906 put_device(&sch->dev);
910 * subchannel recognition done. Called from the state machine.
913 io_subchannel_recog_done(struct ccw_device *cdev)
915 if (css_init_done == 0) {
916 cdev->private->flags.recog_done = 1;
919 switch (cdev->private->state) {
920 case DEV_STATE_BOXED:
921 /* Device did not respond in time. */
922 case DEV_STATE_NOT_OPER:
923 cdev->private->flags.recog_done = 1;
924 /* Remove device found not operational. */
925 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
926 if (atomic_dec_and_test(&ccw_device_init_count))
927 wake_up(&ccw_device_init_wq);
929 case DEV_STATE_OFFLINE:
931 * We can't register the device in interrupt context so
932 * we schedule a work item.
934 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
939 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
941 /* Increase counter of devices currently in recognition. */
942 atomic_inc(&ccw_device_init_count);
944 /* Start async. device sensing. */
945 spin_lock_irq(sch->lock);
946 ccw_device_recognition(cdev);
947 spin_unlock_irq(sch->lock);
950 static int ccw_device_move_to_sch(struct ccw_device *cdev,
951 struct subchannel *sch)
953 struct subchannel *old_sch;
954 int rc, old_enabled = 0;
956 old_sch = to_subchannel(cdev->dev.parent);
957 /* Obtain child reference for new parent. */
958 if (!get_device(&sch->dev))
961 if (!sch_is_pseudo_sch(old_sch)) {
962 spin_lock_irq(old_sch->lock);
963 old_enabled = old_sch->schib.pmcw.ena;
966 rc = cio_disable_subchannel(old_sch);
967 spin_unlock_irq(old_sch->lock);
969 /* Release child reference for new parent. */
970 put_device(&sch->dev);
975 mutex_lock(&sch->reg_mutex);
976 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
977 mutex_unlock(&sch->reg_mutex);
979 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
980 cdev->private->dev_id.ssid,
981 cdev->private->dev_id.devno, sch->schid.ssid,
982 sch->schib.pmcw.dev, rc);
984 /* Try to reenable the old subchannel. */
985 spin_lock_irq(old_sch->lock);
986 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
987 spin_unlock_irq(old_sch->lock);
989 /* Release child reference for new parent. */
990 put_device(&sch->dev);
993 /* Clean up old subchannel. */
994 if (!sch_is_pseudo_sch(old_sch)) {
995 spin_lock_irq(old_sch->lock);
996 sch_set_cdev(old_sch, NULL);
997 spin_unlock_irq(old_sch->lock);
998 css_schedule_eval(old_sch->schid);
1000 /* Release child reference for old parent. */
1001 put_device(&old_sch->dev);
1002 /* Initialize new subchannel. */
1003 spin_lock_irq(sch->lock);
1004 cdev->ccwlock = sch->lock;
1005 if (!sch_is_pseudo_sch(sch))
1006 sch_set_cdev(sch, cdev);
1007 spin_unlock_irq(sch->lock);
1008 if (!sch_is_pseudo_sch(sch))
1009 css_update_ssd_info(sch);
1013 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1015 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1016 struct channel_subsystem *css = to_css(sch->dev.parent);
1018 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1021 static void io_subchannel_irq(struct subchannel *sch)
1023 struct ccw_device *cdev;
1025 cdev = sch_get_cdev(sch);
1027 CIO_TRACE_EVENT(6, "IRQ");
1028 CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1030 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1032 inc_irq_stat(IRQIO_CIO);
1035 void io_subchannel_init_config(struct subchannel *sch)
1037 memset(&sch->config, 0, sizeof(sch->config));
1038 sch->config.csense = 1;
1041 static void io_subchannel_init_fields(struct subchannel *sch)
1043 if (cio_is_console(sch->schid))
1046 sch->opm = chp_get_sch_opm(sch);
1047 sch->lpm = sch->schib.pmcw.pam & sch->opm;
1048 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1050 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1051 " - PIM = %02X, PAM = %02X, POM = %02X\n",
1052 sch->schib.pmcw.dev, sch->schid.ssid,
1053 sch->schid.sch_no, sch->schib.pmcw.pim,
1054 sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1056 io_subchannel_init_config(sch);
1060 * Note: We always return 0 so that we bind to the device even on error.
1061 * This is needed so that our remove function is called on unregister.
1063 static int io_subchannel_probe(struct subchannel *sch)
1065 struct io_subchannel_private *io_priv;
1066 struct ccw_device *cdev;
1069 if (cio_is_console(sch->schid)) {
1070 rc = sysfs_create_group(&sch->dev.kobj,
1071 &io_subchannel_attr_group);
1073 CIO_MSG_EVENT(0, "Failed to create io subchannel "
1074 "attributes for subchannel "
1075 "0.%x.%04x (rc=%d)\n",
1076 sch->schid.ssid, sch->schid.sch_no, rc);
1078 * The console subchannel already has an associated ccw_device.
1079 * Throw the delayed uevent for the subchannel, register
1080 * the ccw_device and exit.
1082 if (dev_get_uevent_suppress(&sch->dev)) {
1083 /* should always be the case for the console */
1084 dev_set_uevent_suppress(&sch->dev, 0);
1085 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1087 cdev = sch_get_cdev(sch);
1088 rc = ccw_device_add(cdev);
1090 /* Release online reference. */
1091 put_device(&cdev->dev);
1094 if (atomic_dec_and_test(&ccw_device_init_count))
1095 wake_up(&ccw_device_init_wq);
1098 io_subchannel_init_fields(sch);
1099 rc = cio_commit_config(sch);
1102 rc = sysfs_create_group(&sch->dev.kobj,
1103 &io_subchannel_attr_group);
1106 /* Allocate I/O subchannel private data. */
1107 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1111 set_io_private(sch, io_priv);
1112 css_schedule_eval(sch->schid);
1116 spin_lock_irq(sch->lock);
1117 css_sched_sch_todo(sch, SCH_TODO_UNREG);
1118 spin_unlock_irq(sch->lock);
1123 io_subchannel_remove (struct subchannel *sch)
1125 struct io_subchannel_private *io_priv = to_io_private(sch);
1126 struct ccw_device *cdev;
1128 cdev = sch_get_cdev(sch);
1131 io_subchannel_quiesce(sch);
1132 /* Set ccw device to not operational and drop reference. */
1133 spin_lock_irq(cdev->ccwlock);
1134 sch_set_cdev(sch, NULL);
1135 set_io_private(sch, NULL);
1136 cdev->private->state = DEV_STATE_NOT_OPER;
1137 spin_unlock_irq(cdev->ccwlock);
1138 ccw_device_unregister(cdev);
1141 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1145 static void io_subchannel_verify(struct subchannel *sch)
1147 struct ccw_device *cdev;
1149 cdev = sch_get_cdev(sch);
1151 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1154 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1156 struct ccw_device *cdev;
1158 cdev = sch_get_cdev(sch);
1161 if (cio_update_schib(sch))
1163 /* Check for I/O on path. */
1164 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1166 if (cdev->private->state == DEV_STATE_ONLINE) {
1167 ccw_device_kill_io(cdev);
1173 /* Trigger path verification. */
1174 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1178 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1181 static int io_subchannel_chp_event(struct subchannel *sch,
1182 struct chp_link *link, int event)
1184 struct ccw_device *cdev = sch_get_cdev(sch);
1187 mask = chp_ssd_get_mask(&sch->ssd_info, link);
1195 cdev->private->path_gone_mask |= mask;
1196 io_subchannel_terminate_path(sch, mask);
1202 cdev->private->path_new_mask |= mask;
1203 io_subchannel_verify(sch);
1206 if (cio_update_schib(sch))
1209 cdev->private->path_gone_mask |= mask;
1210 io_subchannel_terminate_path(sch, mask);
1213 if (cio_update_schib(sch))
1215 sch->lpm |= mask & sch->opm;
1217 cdev->private->path_new_mask |= mask;
1218 io_subchannel_verify(sch);
1224 static void io_subchannel_quiesce(struct subchannel *sch)
1226 struct ccw_device *cdev;
1229 spin_lock_irq(sch->lock);
1230 cdev = sch_get_cdev(sch);
1231 if (cio_is_console(sch->schid))
1233 if (!sch->schib.pmcw.ena)
1235 ret = cio_disable_subchannel(sch);
1239 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1240 while (ret == -EBUSY) {
1241 cdev->private->state = DEV_STATE_QUIESCE;
1242 cdev->private->iretry = 255;
1243 ret = ccw_device_cancel_halt_clear(cdev);
1244 if (ret == -EBUSY) {
1245 ccw_device_set_timeout(cdev, HZ/10);
1246 spin_unlock_irq(sch->lock);
1247 wait_event(cdev->private->wait_q,
1248 cdev->private->state != DEV_STATE_QUIESCE);
1249 spin_lock_irq(sch->lock);
1251 ret = cio_disable_subchannel(sch);
1254 spin_unlock_irq(sch->lock);
1257 static void io_subchannel_shutdown(struct subchannel *sch)
1259 io_subchannel_quiesce(sch);
1262 static int device_is_disconnected(struct ccw_device *cdev)
1266 return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1267 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1270 static int recovery_check(struct device *dev, void *data)
1272 struct ccw_device *cdev = to_ccwdev(dev);
1275 spin_lock_irq(cdev->ccwlock);
1276 switch (cdev->private->state) {
1277 case DEV_STATE_DISCONNECTED:
1278 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1279 cdev->private->dev_id.ssid,
1280 cdev->private->dev_id.devno);
1281 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1284 case DEV_STATE_DISCONNECTED_SENSE_ID:
1288 spin_unlock_irq(cdev->ccwlock);
1293 static void recovery_work_func(struct work_struct *unused)
1297 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1299 spin_lock_irq(&recovery_lock);
1300 if (!timer_pending(&recovery_timer)) {
1301 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1303 mod_timer(&recovery_timer, jiffies +
1304 recovery_delay[recovery_phase] * HZ);
1306 spin_unlock_irq(&recovery_lock);
1308 CIO_MSG_EVENT(4, "recovery: end\n");
1311 static DECLARE_WORK(recovery_work, recovery_work_func);
1313 static void recovery_func(unsigned long data)
1316 * We can't do our recovery in softirq context and it's not
1317 * performance critical, so we schedule it.
1319 schedule_work(&recovery_work);
1322 static void ccw_device_schedule_recovery(void)
1324 unsigned long flags;
1326 CIO_MSG_EVENT(4, "recovery: schedule\n");
1327 spin_lock_irqsave(&recovery_lock, flags);
1328 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1330 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1332 spin_unlock_irqrestore(&recovery_lock, flags);
1335 static int purge_fn(struct device *dev, void *data)
1337 struct ccw_device *cdev = to_ccwdev(dev);
1338 struct ccw_dev_id *id = &cdev->private->dev_id;
1340 spin_lock_irq(cdev->ccwlock);
1341 if (is_blacklisted(id->ssid, id->devno) &&
1342 (cdev->private->state == DEV_STATE_OFFLINE) &&
1343 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1344 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1346 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1347 atomic_set(&cdev->private->onoff, 0);
1349 spin_unlock_irq(cdev->ccwlock);
1350 /* Abort loop in case of pending signal. */
1351 if (signal_pending(current))
1358 * ccw_purge_blacklisted - purge unused, blacklisted devices
1360 * Unregister all ccw devices that are offline and on the blacklist.
1362 int ccw_purge_blacklisted(void)
1364 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1365 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1369 void ccw_device_set_disconnected(struct ccw_device *cdev)
1373 ccw_device_set_timeout(cdev, 0);
1374 cdev->private->flags.fake_irb = 0;
1375 cdev->private->state = DEV_STATE_DISCONNECTED;
1377 ccw_device_schedule_recovery();
1380 void ccw_device_set_notoper(struct ccw_device *cdev)
1382 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1384 CIO_TRACE_EVENT(2, "notoper");
1385 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1386 ccw_device_set_timeout(cdev, 0);
1387 cio_disable_subchannel(sch);
1388 cdev->private->state = DEV_STATE_NOT_OPER;
1391 enum io_sch_action {
1395 IO_SCH_UNREG_ATTACH,
1403 static enum io_sch_action sch_get_action(struct subchannel *sch)
1405 struct ccw_device *cdev;
1407 cdev = sch_get_cdev(sch);
1408 if (cio_update_schib(sch)) {
1409 /* Not operational. */
1411 return IO_SCH_UNREG;
1412 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1413 return IO_SCH_UNREG;
1414 return IO_SCH_ORPH_UNREG;
1418 return IO_SCH_ATTACH;
1419 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1420 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1421 return IO_SCH_UNREG_ATTACH;
1422 return IO_SCH_ORPH_ATTACH;
1424 if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1425 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1426 return IO_SCH_UNREG;
1429 if (device_is_disconnected(cdev))
1430 return IO_SCH_REPROBE;
1431 if (cdev->online && !cdev->private->flags.resuming)
1432 return IO_SCH_VERIFY;
1433 if (cdev->private->state == DEV_STATE_NOT_OPER)
1434 return IO_SCH_UNREG_ATTACH;
1439 * io_subchannel_sch_event - process subchannel event
1441 * @process: non-zero if function is called in process context
1443 * An unspecified event occurred for this subchannel. Adjust data according
1444 * to the current operational state of the subchannel and device. Return
1445 * zero when the event has been handled sufficiently or -EAGAIN when this
1446 * function should be called again in process context.
1448 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1450 unsigned long flags;
1451 struct ccw_device *cdev;
1452 struct ccw_dev_id dev_id;
1453 enum io_sch_action action;
1456 spin_lock_irqsave(sch->lock, flags);
1457 if (!device_is_registered(&sch->dev))
1459 if (work_pending(&sch->todo_work))
1461 cdev = sch_get_cdev(sch);
1462 if (cdev && work_pending(&cdev->private->todo_work))
1464 action = sch_get_action(sch);
1465 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1466 sch->schid.ssid, sch->schid.sch_no, process,
1468 /* Perform immediate actions while holding the lock. */
1470 case IO_SCH_REPROBE:
1471 /* Trigger device recognition. */
1472 ccw_device_trigger_reprobe(cdev);
1476 /* Trigger path verification. */
1477 io_subchannel_verify(sch);
1481 ccw_device_set_disconnected(cdev);
1484 case IO_SCH_ORPH_UNREG:
1485 case IO_SCH_ORPH_ATTACH:
1486 ccw_device_set_disconnected(cdev);
1488 case IO_SCH_UNREG_ATTACH:
1492 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1494 * Note: delayed work triggered by this event
1495 * and repeated calls to sch_event are synchronized
1496 * by the above check for work_pending(cdev).
1498 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1500 ccw_device_set_notoper(cdev);
1508 spin_unlock_irqrestore(sch->lock, flags);
1509 /* All other actions require process context. */
1512 /* Handle attached ccw device. */
1514 case IO_SCH_ORPH_UNREG:
1515 case IO_SCH_ORPH_ATTACH:
1516 /* Move ccw device to orphanage. */
1517 rc = ccw_device_move_to_orph(cdev);
1521 case IO_SCH_UNREG_ATTACH:
1522 spin_lock_irqsave(sch->lock, flags);
1523 if (cdev->private->flags.resuming) {
1524 /* Device will be handled later. */
1528 sch_set_cdev(sch, NULL);
1529 spin_unlock_irqrestore(sch->lock, flags);
1530 /* Unregister ccw device. */
1531 ccw_device_unregister(cdev);
1536 /* Handle subchannel. */
1538 case IO_SCH_ORPH_UNREG:
1540 if (!cdev || !cdev->private->flags.resuming)
1541 css_sch_device_unregister(sch);
1543 case IO_SCH_ORPH_ATTACH:
1544 case IO_SCH_UNREG_ATTACH:
1546 dev_id.ssid = sch->schid.ssid;
1547 dev_id.devno = sch->schib.pmcw.dev;
1548 cdev = get_ccwdev_by_dev_id(&dev_id);
1550 sch_create_and_recog_new_device(sch);
1553 rc = ccw_device_move_to_sch(cdev, sch);
1555 /* Release reference from get_ccwdev_by_dev_id() */
1556 put_device(&cdev->dev);
1559 spin_lock_irqsave(sch->lock, flags);
1560 ccw_device_trigger_reprobe(cdev);
1561 spin_unlock_irqrestore(sch->lock, flags);
1562 /* Release reference from get_ccwdev_by_dev_id() */
1563 put_device(&cdev->dev);
1571 spin_unlock_irqrestore(sch->lock, flags);
1576 static void ccw_device_set_int_class(struct ccw_device *cdev)
1578 struct ccw_driver *cdrv = cdev->drv;
1580 /* Note: we interpret class 0 in this context as an uninitialized
1581 * field since it translates to a non-I/O interrupt class. */
1582 if (cdrv->int_class != 0)
1583 cdev->private->int_class = cdrv->int_class;
1585 cdev->private->int_class = IRQIO_CIO;
1588 #ifdef CONFIG_CCW_CONSOLE
1589 int __init ccw_device_enable_console(struct ccw_device *cdev)
1591 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1594 if (!cdev->drv || !cdev->handler)
1597 io_subchannel_init_fields(sch);
1598 rc = cio_commit_config(sch);
1601 sch->driver = &io_subchannel_driver;
1602 io_subchannel_recog(cdev, sch);
1603 /* Now wait for the async. recognition to come to an end. */
1604 spin_lock_irq(cdev->ccwlock);
1605 while (!dev_fsm_final_state(cdev))
1606 ccw_device_wait_idle(cdev);
1608 /* Hold on to an extra reference while device is online. */
1609 get_device(&cdev->dev);
1610 rc = ccw_device_online(cdev);
1614 while (!dev_fsm_final_state(cdev))
1615 ccw_device_wait_idle(cdev);
1617 if (cdev->private->state == DEV_STATE_ONLINE)
1622 spin_unlock_irq(cdev->ccwlock);
1623 if (rc) /* Give up online reference since onlining failed. */
1624 put_device(&cdev->dev);
1628 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1630 struct io_subchannel_private *io_priv;
1631 struct ccw_device *cdev;
1632 struct subchannel *sch;
1634 sch = cio_probe_console();
1636 return ERR_CAST(sch);
1638 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1640 put_device(&sch->dev);
1641 return ERR_PTR(-ENOMEM);
1643 set_io_private(sch, io_priv);
1644 cdev = io_subchannel_create_ccwdev(sch);
1646 put_device(&sch->dev);
1651 ccw_device_set_int_class(cdev);
1655 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1657 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1658 struct io_subchannel_private *io_priv = to_io_private(sch);
1660 set_io_private(sch, NULL);
1661 put_device(&sch->dev);
1662 put_device(&cdev->dev);
1667 * ccw_device_wait_idle() - busy wait for device to become idle
1670 * Poll until activity control is zero, that is, no function or data
1671 * transfer is pending/active.
1672 * Called with device lock being held.
1674 void ccw_device_wait_idle(struct ccw_device *cdev)
1676 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1680 if (sch->schib.scsw.cmd.actl == 0)
1686 static int ccw_device_pm_restore(struct device *dev);
1688 int ccw_device_force_console(struct ccw_device *cdev)
1690 return ccw_device_pm_restore(&cdev->dev);
1692 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1696 * get ccw_device matching the busid, but only if owned by cdrv
1699 __ccwdev_check_busid(struct device *dev, void *id)
1705 return (strcmp(bus_id, dev_name(dev)) == 0);
1710 * get_ccwdev_by_busid() - obtain device from a bus id
1711 * @cdrv: driver the device is owned by
1712 * @bus_id: bus id of the device to be searched
1714 * This function searches all devices owned by @cdrv for a device with a bus
1715 * id matching @bus_id.
1717 * If a match is found, its reference count of the found device is increased
1718 * and it is returned; else %NULL is returned.
1720 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1725 dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1726 __ccwdev_check_busid);
1728 return dev ? to_ccwdev(dev) : NULL;
1731 /************************** device driver handling ************************/
1733 /* This is the implementation of the ccw_driver class. The probe, remove
1734 * and release methods are initially very similar to the device_driver
1735 * implementations, with the difference that they have ccw_device
1738 * A ccw driver also contains the information that is needed for
1742 ccw_device_probe (struct device *dev)
1744 struct ccw_device *cdev = to_ccwdev(dev);
1745 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1748 cdev->drv = cdrv; /* to let the driver call _set_online */
1749 ccw_device_set_int_class(cdev);
1750 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1753 cdev->private->int_class = IRQIO_CIO;
1760 static int ccw_device_remove(struct device *dev)
1762 struct ccw_device *cdev = to_ccwdev(dev);
1763 struct ccw_driver *cdrv = cdev->drv;
1769 spin_lock_irq(cdev->ccwlock);
1772 ret = ccw_device_offline(cdev);
1773 spin_unlock_irq(cdev->ccwlock);
1775 wait_event(cdev->private->wait_q,
1776 dev_fsm_final_state(cdev));
1778 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1779 "device 0.%x.%04x\n",
1780 ret, cdev->private->dev_id.ssid,
1781 cdev->private->dev_id.devno);
1782 /* Give up reference obtained in ccw_device_set_online(). */
1783 put_device(&cdev->dev);
1784 spin_lock_irq(cdev->ccwlock);
1786 ccw_device_set_timeout(cdev, 0);
1788 cdev->private->int_class = IRQIO_CIO;
1789 spin_unlock_irq(cdev->ccwlock);
1790 __disable_cmf(cdev);
1795 static void ccw_device_shutdown(struct device *dev)
1797 struct ccw_device *cdev;
1799 cdev = to_ccwdev(dev);
1800 if (cdev->drv && cdev->drv->shutdown)
1801 cdev->drv->shutdown(cdev);
1802 __disable_cmf(cdev);
1805 static int ccw_device_pm_prepare(struct device *dev)
1807 struct ccw_device *cdev = to_ccwdev(dev);
1809 if (work_pending(&cdev->private->todo_work))
1811 /* Fail while device is being set online/offline. */
1812 if (atomic_read(&cdev->private->onoff))
1815 if (cdev->online && cdev->drv && cdev->drv->prepare)
1816 return cdev->drv->prepare(cdev);
1821 static void ccw_device_pm_complete(struct device *dev)
1823 struct ccw_device *cdev = to_ccwdev(dev);
1825 if (cdev->online && cdev->drv && cdev->drv->complete)
1826 cdev->drv->complete(cdev);
1829 static int ccw_device_pm_freeze(struct device *dev)
1831 struct ccw_device *cdev = to_ccwdev(dev);
1832 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1833 int ret, cm_enabled;
1835 /* Fail suspend while device is in transistional state. */
1836 if (!dev_fsm_final_state(cdev))
1840 if (cdev->drv && cdev->drv->freeze) {
1841 ret = cdev->drv->freeze(cdev);
1846 spin_lock_irq(sch->lock);
1847 cm_enabled = cdev->private->cmb != NULL;
1848 spin_unlock_irq(sch->lock);
1850 /* Don't have the css write on memory. */
1851 ret = ccw_set_cmf(cdev, 0);
1855 /* From here on, disallow device driver I/O. */
1856 spin_lock_irq(sch->lock);
1857 ret = cio_disable_subchannel(sch);
1858 spin_unlock_irq(sch->lock);
1863 static int ccw_device_pm_thaw(struct device *dev)
1865 struct ccw_device *cdev = to_ccwdev(dev);
1866 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1867 int ret, cm_enabled;
1872 spin_lock_irq(sch->lock);
1873 /* Allow device driver I/O again. */
1874 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1875 cm_enabled = cdev->private->cmb != NULL;
1876 spin_unlock_irq(sch->lock);
1881 ret = ccw_set_cmf(cdev, 1);
1886 if (cdev->drv && cdev->drv->thaw)
1887 ret = cdev->drv->thaw(cdev);
1892 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1894 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1896 spin_lock_irq(sch->lock);
1897 if (cio_is_console(sch->schid)) {
1898 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1902 * While we were sleeping, devices may have gone or become
1903 * available again. Kick re-detection.
1905 cdev->private->flags.resuming = 1;
1906 cdev->private->path_new_mask = LPM_ANYPATH;
1907 css_sched_sch_todo(sch, SCH_TODO_EVAL);
1908 spin_unlock_irq(sch->lock);
1909 css_wait_for_slow_path();
1911 /* cdev may have been moved to a different subchannel. */
1912 sch = to_subchannel(cdev->dev.parent);
1913 spin_lock_irq(sch->lock);
1914 if (cdev->private->state != DEV_STATE_ONLINE &&
1915 cdev->private->state != DEV_STATE_OFFLINE)
1918 ccw_device_recognition(cdev);
1919 spin_unlock_irq(sch->lock);
1920 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1921 cdev->private->state == DEV_STATE_DISCONNECTED);
1922 spin_lock_irq(sch->lock);
1925 cdev->private->flags.resuming = 0;
1926 spin_unlock_irq(sch->lock);
1929 static int resume_handle_boxed(struct ccw_device *cdev)
1931 cdev->private->state = DEV_STATE_BOXED;
1932 if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1934 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1938 static int resume_handle_disc(struct ccw_device *cdev)
1940 cdev->private->state = DEV_STATE_DISCONNECTED;
1941 if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1943 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1947 static int ccw_device_pm_restore(struct device *dev)
1949 struct ccw_device *cdev = to_ccwdev(dev);
1950 struct subchannel *sch;
1953 __ccw_device_pm_restore(cdev);
1954 sch = to_subchannel(cdev->dev.parent);
1955 spin_lock_irq(sch->lock);
1956 if (cio_is_console(sch->schid))
1959 /* check recognition results */
1960 switch (cdev->private->state) {
1961 case DEV_STATE_OFFLINE:
1962 case DEV_STATE_ONLINE:
1963 cdev->private->flags.donotify = 0;
1965 case DEV_STATE_BOXED:
1966 ret = resume_handle_boxed(cdev);
1971 ret = resume_handle_disc(cdev);
1976 /* check if the device type has changed */
1977 if (!ccw_device_test_sense_data(cdev)) {
1978 ccw_device_update_sense_data(cdev);
1979 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1986 if (ccw_device_online(cdev)) {
1987 ret = resume_handle_disc(cdev);
1992 spin_unlock_irq(sch->lock);
1993 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1994 spin_lock_irq(sch->lock);
1996 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1997 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
2002 /* reenable cmf, if needed */
2003 if (cdev->private->cmb) {
2004 spin_unlock_irq(sch->lock);
2005 ret = ccw_set_cmf(cdev, 1);
2006 spin_lock_irq(sch->lock);
2008 CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2009 "(rc=%d)\n", cdev->private->dev_id.ssid,
2010 cdev->private->dev_id.devno, ret);
2016 spin_unlock_irq(sch->lock);
2017 if (cdev->online && cdev->drv && cdev->drv->restore)
2018 ret = cdev->drv->restore(cdev);
2022 spin_unlock_irq(sch->lock);
2026 static const struct dev_pm_ops ccw_pm_ops = {
2027 .prepare = ccw_device_pm_prepare,
2028 .complete = ccw_device_pm_complete,
2029 .freeze = ccw_device_pm_freeze,
2030 .thaw = ccw_device_pm_thaw,
2031 .restore = ccw_device_pm_restore,
2034 static struct bus_type ccw_bus_type = {
2036 .match = ccw_bus_match,
2037 .uevent = ccw_uevent,
2038 .probe = ccw_device_probe,
2039 .remove = ccw_device_remove,
2040 .shutdown = ccw_device_shutdown,
2045 * ccw_driver_register() - register a ccw driver
2046 * @cdriver: driver to be registered
2048 * This function is mainly a wrapper around driver_register().
2050 * %0 on success and a negative error value on failure.
2052 int ccw_driver_register(struct ccw_driver *cdriver)
2054 struct device_driver *drv = &cdriver->driver;
2056 drv->bus = &ccw_bus_type;
2058 return driver_register(drv);
2062 * ccw_driver_unregister() - deregister a ccw driver
2063 * @cdriver: driver to be deregistered
2065 * This function is mainly a wrapper around driver_unregister().
2067 void ccw_driver_unregister(struct ccw_driver *cdriver)
2069 driver_unregister(&cdriver->driver);
2072 static void ccw_device_todo(struct work_struct *work)
2074 struct ccw_device_private *priv;
2075 struct ccw_device *cdev;
2076 struct subchannel *sch;
2077 enum cdev_todo todo;
2079 priv = container_of(work, struct ccw_device_private, todo_work);
2081 sch = to_subchannel(cdev->dev.parent);
2082 /* Find out todo. */
2083 spin_lock_irq(cdev->ccwlock);
2085 priv->todo = CDEV_TODO_NOTHING;
2086 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2087 priv->dev_id.ssid, priv->dev_id.devno, todo);
2088 spin_unlock_irq(cdev->ccwlock);
2091 case CDEV_TODO_ENABLE_CMF:
2094 case CDEV_TODO_REBIND:
2095 ccw_device_do_unbind_bind(cdev);
2097 case CDEV_TODO_REGISTER:
2098 io_subchannel_register(cdev);
2100 case CDEV_TODO_UNREG_EVAL:
2101 if (!sch_is_pseudo_sch(sch))
2102 css_schedule_eval(sch->schid);
2104 case CDEV_TODO_UNREG:
2105 if (sch_is_pseudo_sch(sch))
2106 ccw_device_unregister(cdev);
2108 ccw_device_call_sch_unregister(cdev);
2113 /* Release workqueue ref. */
2114 put_device(&cdev->dev);
2118 * ccw_device_sched_todo - schedule ccw device operation
2122 * Schedule the operation identified by @todo to be performed on the slow path
2123 * workqueue. Do nothing if another operation with higher priority is already
2124 * scheduled. Needs to be called with ccwdev lock held.
2126 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2128 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2129 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2131 if (cdev->private->todo >= todo)
2133 cdev->private->todo = todo;
2134 /* Get workqueue ref. */
2135 if (!get_device(&cdev->dev))
2137 if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2138 /* Already queued, release workqueue ref. */
2139 put_device(&cdev->dev);
2144 * ccw_device_siosl() - initiate logging
2147 * This function is used to invoke model-dependent logging within the channel
2150 int ccw_device_siosl(struct ccw_device *cdev)
2152 struct subchannel *sch = to_subchannel(cdev->dev.parent);
2154 return chsc_siosl(sch->schid);
2156 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2158 MODULE_LICENSE("GPL");
2159 EXPORT_SYMBOL(ccw_device_set_online);
2160 EXPORT_SYMBOL(ccw_device_set_offline);
2161 EXPORT_SYMBOL(ccw_driver_register);
2162 EXPORT_SYMBOL(ccw_driver_unregister);
2163 EXPORT_SYMBOL(get_ccwdev_by_busid);