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);
337 spin_lock_irq(cdev->ccwlock);
338 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_warning("%s: The device entered boxed state while "
368 "being set offline\n", dev_name(&cdev->dev));
369 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
370 pr_warning("%s: The device stopped operating while "
371 "being set offline\n", 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_warning("%s: Setting the device online failed "
433 "because it is boxed\n",
434 dev_name(&cdev->dev));
435 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
436 pr_warning("%s: Setting the device online failed "
437 "because it is not operational\n",
438 dev_name(&cdev->dev));
440 /* Give up online reference since onlining failed. */
441 put_device(&cdev->dev);
444 spin_unlock_irq(cdev->ccwlock);
445 if (cdev->drv->set_online)
446 ret = cdev->drv->set_online(cdev);
453 spin_lock_irq(cdev->ccwlock);
454 /* Wait until a final state or DISCONNECTED is reached */
455 while (!dev_fsm_final_state(cdev) &&
456 cdev->private->state != DEV_STATE_DISCONNECTED) {
457 spin_unlock_irq(cdev->ccwlock);
458 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
459 cdev->private->state == DEV_STATE_DISCONNECTED));
460 spin_lock_irq(cdev->ccwlock);
462 ret2 = ccw_device_offline(cdev);
465 spin_unlock_irq(cdev->ccwlock);
466 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
467 cdev->private->state == DEV_STATE_DISCONNECTED));
468 /* Give up online reference since onlining failed. */
469 put_device(&cdev->dev);
473 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
474 "device 0.%x.%04x\n",
475 ret2, cdev->private->dev_id.ssid,
476 cdev->private->dev_id.devno);
477 cdev->private->state = DEV_STATE_OFFLINE;
478 spin_unlock_irq(cdev->ccwlock);
479 /* Give up online reference since onlining failed. */
480 put_device(&cdev->dev);
484 static int online_store_handle_offline(struct ccw_device *cdev)
486 if (cdev->private->state == DEV_STATE_DISCONNECTED) {
487 spin_lock_irq(cdev->ccwlock);
488 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
489 spin_unlock_irq(cdev->ccwlock);
492 if (cdev->drv && cdev->drv->set_offline)
493 return ccw_device_set_offline(cdev);
497 static int online_store_recog_and_online(struct ccw_device *cdev)
499 /* Do device recognition, if needed. */
500 if (cdev->private->state == DEV_STATE_BOXED) {
501 spin_lock_irq(cdev->ccwlock);
502 ccw_device_recognition(cdev);
503 spin_unlock_irq(cdev->ccwlock);
504 wait_event(cdev->private->wait_q,
505 cdev->private->flags.recog_done);
506 if (cdev->private->state != DEV_STATE_OFFLINE)
507 /* recognition failed */
510 if (cdev->drv && cdev->drv->set_online)
511 return ccw_device_set_online(cdev);
515 static int online_store_handle_online(struct ccw_device *cdev, int force)
519 ret = online_store_recog_and_online(cdev);
522 if (force && cdev->private->state == DEV_STATE_BOXED) {
523 ret = ccw_device_stlck(cdev);
526 if (cdev->id.cu_type == 0)
527 cdev->private->state = DEV_STATE_NOT_OPER;
528 ret = online_store_recog_and_online(cdev);
535 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
536 const char *buf, size_t count)
538 struct ccw_device *cdev = to_ccwdev(dev);
542 /* Prevent conflict between multiple on-/offline processing requests. */
543 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
545 /* Prevent conflict between internal I/Os and on-/offline processing. */
546 if (!dev_fsm_final_state(cdev) &&
547 cdev->private->state != DEV_STATE_DISCONNECTED) {
551 /* Prevent conflict between pending work and on-/offline processing.*/
552 if (work_pending(&cdev->private->todo_work)) {
557 if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
561 if (!strncmp(buf, "force\n", count)) {
567 ret = kstrtoul(buf, 16, &i);
573 ret = online_store_handle_offline(cdev);
576 ret = online_store_handle_online(cdev, force);
583 module_put(cdev->drv->driver.owner);
585 atomic_set(&cdev->private->onoff, 0);
586 return (ret < 0) ? ret : count;
590 available_show (struct device *dev, struct device_attribute *attr, char *buf)
592 struct ccw_device *cdev = to_ccwdev(dev);
593 struct subchannel *sch;
595 if (ccw_device_is_orphan(cdev))
596 return sprintf(buf, "no device\n");
597 switch (cdev->private->state) {
598 case DEV_STATE_BOXED:
599 return sprintf(buf, "boxed\n");
600 case DEV_STATE_DISCONNECTED:
601 case DEV_STATE_DISCONNECTED_SENSE_ID:
602 case DEV_STATE_NOT_OPER:
603 sch = to_subchannel(dev->parent);
605 return sprintf(buf, "no path\n");
607 return sprintf(buf, "no device\n");
609 /* All other states considered fine. */
610 return sprintf(buf, "good\n");
615 initiate_logging(struct device *dev, struct device_attribute *attr,
616 const char *buf, size_t count)
618 struct subchannel *sch = to_subchannel(dev);
621 rc = chsc_siosl(sch->schid);
623 pr_warning("Logging for subchannel 0.%x.%04x failed with "
625 sch->schid.ssid, sch->schid.sch_no, rc);
628 pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
629 sch->schid.ssid, sch->schid.sch_no);
633 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
636 struct subchannel *sch = to_subchannel(dev);
638 return sprintf(buf, "%02x\n", sch->vpm);
641 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
642 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
643 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
644 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
645 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
646 static DEVICE_ATTR(online, 0644, online_show, online_store);
647 static DEVICE_ATTR(availability, 0444, available_show, NULL);
648 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
649 static DEVICE_ATTR(vpm, 0444, vpm_show, NULL);
651 static struct attribute *io_subchannel_attrs[] = {
652 &dev_attr_chpids.attr,
653 &dev_attr_pimpampom.attr,
654 &dev_attr_logging.attr,
659 static struct attribute_group io_subchannel_attr_group = {
660 .attrs = io_subchannel_attrs,
663 static struct attribute * ccwdev_attrs[] = {
664 &dev_attr_devtype.attr,
665 &dev_attr_cutype.attr,
666 &dev_attr_modalias.attr,
667 &dev_attr_online.attr,
668 &dev_attr_cmb_enable.attr,
669 &dev_attr_availability.attr,
673 static struct attribute_group ccwdev_attr_group = {
674 .attrs = ccwdev_attrs,
677 static const struct attribute_group *ccwdev_attr_groups[] = {
682 /* this is a simple abstraction for device_register that sets the
683 * correct bus type and adds the bus specific files */
684 static int ccw_device_register(struct ccw_device *cdev)
686 struct device *dev = &cdev->dev;
689 dev->bus = &ccw_bus_type;
690 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
691 cdev->private->dev_id.devno);
694 return device_add(dev);
697 static int match_dev_id(struct device *dev, void *data)
699 struct ccw_device *cdev = to_ccwdev(dev);
700 struct ccw_dev_id *dev_id = data;
702 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
706 * get_ccwdev_by_dev_id() - obtain device from a ccw device id
707 * @dev_id: id of the device to be searched
709 * This function searches all devices attached to the ccw bus for a device
712 * If a device is found its reference count is increased and returned;
713 * else %NULL is returned.
715 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
719 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
721 return dev ? to_ccwdev(dev) : NULL;
723 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
725 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
729 if (device_is_registered(&cdev->dev)) {
730 device_release_driver(&cdev->dev);
731 ret = device_attach(&cdev->dev);
732 WARN_ON(ret == -ENODEV);
737 ccw_device_release(struct device *dev)
739 struct ccw_device *cdev;
741 cdev = to_ccwdev(dev);
742 /* Release reference of parent subchannel. */
743 put_device(cdev->dev.parent);
744 kfree(cdev->private);
748 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
750 struct ccw_device *cdev;
752 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
754 cdev->private = kzalloc(sizeof(struct ccw_device_private),
755 GFP_KERNEL | GFP_DMA);
760 return ERR_PTR(-ENOMEM);
763 static void ccw_device_todo(struct work_struct *work);
765 static int io_subchannel_initialize_dev(struct subchannel *sch,
766 struct ccw_device *cdev)
768 cdev->private->cdev = cdev;
769 cdev->private->int_class = IRQIO_CIO;
770 atomic_set(&cdev->private->onoff, 0);
771 cdev->dev.parent = &sch->dev;
772 cdev->dev.release = ccw_device_release;
773 INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
774 cdev->dev.groups = ccwdev_attr_groups;
775 /* Do first half of device_register. */
776 device_initialize(&cdev->dev);
777 if (!get_device(&sch->dev)) {
778 /* Release reference from device_initialize(). */
779 put_device(&cdev->dev);
782 cdev->private->flags.initialized = 1;
786 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
788 struct ccw_device *cdev;
791 cdev = io_subchannel_allocate_dev(sch);
793 ret = io_subchannel_initialize_dev(sch, cdev);
800 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
802 static void sch_create_and_recog_new_device(struct subchannel *sch)
804 struct ccw_device *cdev;
806 /* Need to allocate a new ccw device. */
807 cdev = io_subchannel_create_ccwdev(sch);
809 /* OK, we did everything we could... */
810 css_sch_device_unregister(sch);
813 /* Start recognition for the new ccw device. */
814 io_subchannel_recog(cdev, sch);
818 * Register recognized device.
820 static void io_subchannel_register(struct ccw_device *cdev)
822 struct subchannel *sch;
823 int ret, adjust_init_count = 1;
826 sch = to_subchannel(cdev->dev.parent);
828 * Check if subchannel is still registered. It may have become
829 * unregistered if a machine check hit us after finishing
830 * device recognition but before the register work could be
833 if (!device_is_registered(&sch->dev))
835 css_update_ssd_info(sch);
837 * io_subchannel_register() will also be called after device
838 * recognition has been done for a boxed device (which will already
839 * be registered). We need to reprobe since we may now have sense id
842 if (device_is_registered(&cdev->dev)) {
844 ret = device_reprobe(&cdev->dev);
846 /* We can't do much here. */
847 CIO_MSG_EVENT(0, "device_reprobe() returned"
848 " %d for 0.%x.%04x\n", ret,
849 cdev->private->dev_id.ssid,
850 cdev->private->dev_id.devno);
852 adjust_init_count = 0;
856 * Now we know this subchannel will stay, we can throw
857 * our delayed uevent.
859 dev_set_uevent_suppress(&sch->dev, 0);
860 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
861 /* make it known to the system */
862 ret = ccw_device_register(cdev);
864 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
865 cdev->private->dev_id.ssid,
866 cdev->private->dev_id.devno, ret);
867 spin_lock_irqsave(sch->lock, flags);
868 sch_set_cdev(sch, NULL);
869 spin_unlock_irqrestore(sch->lock, flags);
870 /* Release initial device reference. */
871 put_device(&cdev->dev);
875 cdev->private->flags.recog_done = 1;
876 wake_up(&cdev->private->wait_q);
878 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
879 wake_up(&ccw_device_init_wq);
882 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
884 struct subchannel *sch;
886 /* Get subchannel reference for local processing. */
887 if (!get_device(cdev->dev.parent))
889 sch = to_subchannel(cdev->dev.parent);
890 css_sch_device_unregister(sch);
891 /* Release subchannel reference for local processing. */
892 put_device(&sch->dev);
896 * subchannel recognition done. Called from the state machine.
899 io_subchannel_recog_done(struct ccw_device *cdev)
901 if (css_init_done == 0) {
902 cdev->private->flags.recog_done = 1;
905 switch (cdev->private->state) {
906 case DEV_STATE_BOXED:
907 /* Device did not respond in time. */
908 case DEV_STATE_NOT_OPER:
909 cdev->private->flags.recog_done = 1;
910 /* Remove device found not operational. */
911 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
912 if (atomic_dec_and_test(&ccw_device_init_count))
913 wake_up(&ccw_device_init_wq);
915 case DEV_STATE_OFFLINE:
917 * We can't register the device in interrupt context so
918 * we schedule a work item.
920 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
925 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
927 struct ccw_device_private *priv;
929 cdev->ccwlock = sch->lock;
931 /* Init private data. */
932 priv = cdev->private;
933 priv->dev_id.devno = sch->schib.pmcw.dev;
934 priv->dev_id.ssid = sch->schid.ssid;
935 priv->schid = sch->schid;
936 priv->state = DEV_STATE_NOT_OPER;
937 INIT_LIST_HEAD(&priv->cmb_list);
938 init_waitqueue_head(&priv->wait_q);
939 init_timer(&priv->timer);
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 sch_set_cdev(sch, cdev);
947 ccw_device_recognition(cdev);
948 spin_unlock_irq(sch->lock);
951 static int ccw_device_move_to_sch(struct ccw_device *cdev,
952 struct subchannel *sch)
954 struct subchannel *old_sch;
955 int rc, old_enabled = 0;
957 old_sch = to_subchannel(cdev->dev.parent);
958 /* Obtain child reference for new parent. */
959 if (!get_device(&sch->dev))
962 if (!sch_is_pseudo_sch(old_sch)) {
963 spin_lock_irq(old_sch->lock);
964 old_enabled = old_sch->schib.pmcw.ena;
967 rc = cio_disable_subchannel(old_sch);
968 spin_unlock_irq(old_sch->lock);
970 /* Release child reference for new parent. */
971 put_device(&sch->dev);
976 mutex_lock(&sch->reg_mutex);
977 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
978 mutex_unlock(&sch->reg_mutex);
980 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
981 cdev->private->dev_id.ssid,
982 cdev->private->dev_id.devno, sch->schid.ssid,
983 sch->schib.pmcw.dev, rc);
985 /* Try to reenable the old subchannel. */
986 spin_lock_irq(old_sch->lock);
987 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
988 spin_unlock_irq(old_sch->lock);
990 /* Release child reference for new parent. */
991 put_device(&sch->dev);
994 /* Clean up old subchannel. */
995 if (!sch_is_pseudo_sch(old_sch)) {
996 spin_lock_irq(old_sch->lock);
997 sch_set_cdev(old_sch, NULL);
998 spin_unlock_irq(old_sch->lock);
999 css_schedule_eval(old_sch->schid);
1001 /* Release child reference for old parent. */
1002 put_device(&old_sch->dev);
1003 /* Initialize new subchannel. */
1004 spin_lock_irq(sch->lock);
1005 cdev->private->schid = sch->schid;
1006 cdev->ccwlock = sch->lock;
1007 if (!sch_is_pseudo_sch(sch))
1008 sch_set_cdev(sch, cdev);
1009 spin_unlock_irq(sch->lock);
1010 if (!sch_is_pseudo_sch(sch))
1011 css_update_ssd_info(sch);
1015 static int ccw_device_move_to_orph(struct ccw_device *cdev)
1017 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1018 struct channel_subsystem *css = to_css(sch->dev.parent);
1020 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1023 static void io_subchannel_irq(struct subchannel *sch)
1025 struct ccw_device *cdev;
1027 cdev = sch_get_cdev(sch);
1029 CIO_TRACE_EVENT(6, "IRQ");
1030 CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1032 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1034 inc_irq_stat(IRQIO_CIO);
1037 void io_subchannel_init_config(struct subchannel *sch)
1039 memset(&sch->config, 0, sizeof(sch->config));
1040 sch->config.csense = 1;
1043 static void io_subchannel_init_fields(struct subchannel *sch)
1045 if (cio_is_console(sch->schid))
1048 sch->opm = chp_get_sch_opm(sch);
1049 sch->lpm = sch->schib.pmcw.pam & sch->opm;
1050 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1052 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1053 " - PIM = %02X, PAM = %02X, POM = %02X\n",
1054 sch->schib.pmcw.dev, sch->schid.ssid,
1055 sch->schid.sch_no, sch->schib.pmcw.pim,
1056 sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1058 io_subchannel_init_config(sch);
1062 * Note: We always return 0 so that we bind to the device even on error.
1063 * This is needed so that our remove function is called on unregister.
1065 static int io_subchannel_probe(struct subchannel *sch)
1067 struct io_subchannel_private *io_priv;
1068 struct ccw_device *cdev;
1071 if (cio_is_console(sch->schid)) {
1072 rc = sysfs_create_group(&sch->dev.kobj,
1073 &io_subchannel_attr_group);
1075 CIO_MSG_EVENT(0, "Failed to create io subchannel "
1076 "attributes for subchannel "
1077 "0.%x.%04x (rc=%d)\n",
1078 sch->schid.ssid, sch->schid.sch_no, rc);
1080 * The console subchannel already has an associated ccw_device.
1081 * Throw the delayed uevent for the subchannel, register
1082 * the ccw_device and exit.
1084 dev_set_uevent_suppress(&sch->dev, 0);
1085 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1086 cdev = sch_get_cdev(sch);
1087 rc = ccw_device_register(cdev);
1089 /* Release online reference. */
1090 put_device(&cdev->dev);
1093 if (atomic_dec_and_test(&ccw_device_init_count))
1094 wake_up(&ccw_device_init_wq);
1097 io_subchannel_init_fields(sch);
1098 rc = cio_commit_config(sch);
1101 rc = sysfs_create_group(&sch->dev.kobj,
1102 &io_subchannel_attr_group);
1105 /* Allocate I/O subchannel private data. */
1106 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1110 set_io_private(sch, io_priv);
1111 css_schedule_eval(sch->schid);
1115 spin_lock_irq(sch->lock);
1116 css_sched_sch_todo(sch, SCH_TODO_UNREG);
1117 spin_unlock_irq(sch->lock);
1122 io_subchannel_remove (struct subchannel *sch)
1124 struct io_subchannel_private *io_priv = to_io_private(sch);
1125 struct ccw_device *cdev;
1127 cdev = sch_get_cdev(sch);
1130 io_subchannel_quiesce(sch);
1131 /* Set ccw device to not operational and drop reference. */
1132 spin_lock_irq(cdev->ccwlock);
1133 sch_set_cdev(sch, NULL);
1134 set_io_private(sch, NULL);
1135 cdev->private->state = DEV_STATE_NOT_OPER;
1136 spin_unlock_irq(cdev->ccwlock);
1137 ccw_device_unregister(cdev);
1140 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1144 static void io_subchannel_verify(struct subchannel *sch)
1146 struct ccw_device *cdev;
1148 cdev = sch_get_cdev(sch);
1150 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1153 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1155 struct ccw_device *cdev;
1157 cdev = sch_get_cdev(sch);
1160 if (cio_update_schib(sch))
1162 /* Check for I/O on path. */
1163 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1165 if (cdev->private->state == DEV_STATE_ONLINE) {
1166 ccw_device_kill_io(cdev);
1172 /* Trigger path verification. */
1173 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1177 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1180 static int io_subchannel_chp_event(struct subchannel *sch,
1181 struct chp_link *link, int event)
1183 struct ccw_device *cdev = sch_get_cdev(sch);
1186 mask = chp_ssd_get_mask(&sch->ssd_info, link);
1194 cdev->private->path_gone_mask |= mask;
1195 io_subchannel_terminate_path(sch, mask);
1201 cdev->private->path_new_mask |= mask;
1202 io_subchannel_verify(sch);
1205 if (cio_update_schib(sch))
1208 cdev->private->path_gone_mask |= mask;
1209 io_subchannel_terminate_path(sch, mask);
1212 if (cio_update_schib(sch))
1214 sch->lpm |= mask & sch->opm;
1216 cdev->private->path_new_mask |= mask;
1217 io_subchannel_verify(sch);
1223 static void io_subchannel_quiesce(struct subchannel *sch)
1225 struct ccw_device *cdev;
1228 spin_lock_irq(sch->lock);
1229 cdev = sch_get_cdev(sch);
1230 if (cio_is_console(sch->schid))
1232 if (!sch->schib.pmcw.ena)
1234 ret = cio_disable_subchannel(sch);
1238 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1239 while (ret == -EBUSY) {
1240 cdev->private->state = DEV_STATE_QUIESCE;
1241 cdev->private->iretry = 255;
1242 ret = ccw_device_cancel_halt_clear(cdev);
1243 if (ret == -EBUSY) {
1244 ccw_device_set_timeout(cdev, HZ/10);
1245 spin_unlock_irq(sch->lock);
1246 wait_event(cdev->private->wait_q,
1247 cdev->private->state != DEV_STATE_QUIESCE);
1248 spin_lock_irq(sch->lock);
1250 ret = cio_disable_subchannel(sch);
1253 spin_unlock_irq(sch->lock);
1256 static void io_subchannel_shutdown(struct subchannel *sch)
1258 io_subchannel_quiesce(sch);
1261 static int device_is_disconnected(struct ccw_device *cdev)
1265 return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1266 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1269 static int recovery_check(struct device *dev, void *data)
1271 struct ccw_device *cdev = to_ccwdev(dev);
1274 spin_lock_irq(cdev->ccwlock);
1275 switch (cdev->private->state) {
1276 case DEV_STATE_DISCONNECTED:
1277 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1278 cdev->private->dev_id.ssid,
1279 cdev->private->dev_id.devno);
1280 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1283 case DEV_STATE_DISCONNECTED_SENSE_ID:
1287 spin_unlock_irq(cdev->ccwlock);
1292 static void recovery_work_func(struct work_struct *unused)
1296 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1298 spin_lock_irq(&recovery_lock);
1299 if (!timer_pending(&recovery_timer)) {
1300 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1302 mod_timer(&recovery_timer, jiffies +
1303 recovery_delay[recovery_phase] * HZ);
1305 spin_unlock_irq(&recovery_lock);
1307 CIO_MSG_EVENT(4, "recovery: end\n");
1310 static DECLARE_WORK(recovery_work, recovery_work_func);
1312 static void recovery_func(unsigned long data)
1315 * We can't do our recovery in softirq context and it's not
1316 * performance critical, so we schedule it.
1318 schedule_work(&recovery_work);
1321 static void ccw_device_schedule_recovery(void)
1323 unsigned long flags;
1325 CIO_MSG_EVENT(4, "recovery: schedule\n");
1326 spin_lock_irqsave(&recovery_lock, flags);
1327 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1329 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1331 spin_unlock_irqrestore(&recovery_lock, flags);
1334 static int purge_fn(struct device *dev, void *data)
1336 struct ccw_device *cdev = to_ccwdev(dev);
1337 struct ccw_dev_id *id = &cdev->private->dev_id;
1339 spin_lock_irq(cdev->ccwlock);
1340 if (is_blacklisted(id->ssid, id->devno) &&
1341 (cdev->private->state == DEV_STATE_OFFLINE) &&
1342 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1343 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1345 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1346 atomic_set(&cdev->private->onoff, 0);
1348 spin_unlock_irq(cdev->ccwlock);
1349 /* Abort loop in case of pending signal. */
1350 if (signal_pending(current))
1357 * ccw_purge_blacklisted - purge unused, blacklisted devices
1359 * Unregister all ccw devices that are offline and on the blacklist.
1361 int ccw_purge_blacklisted(void)
1363 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1364 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1368 void ccw_device_set_disconnected(struct ccw_device *cdev)
1372 ccw_device_set_timeout(cdev, 0);
1373 cdev->private->flags.fake_irb = 0;
1374 cdev->private->state = DEV_STATE_DISCONNECTED;
1376 ccw_device_schedule_recovery();
1379 void ccw_device_set_notoper(struct ccw_device *cdev)
1381 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1383 CIO_TRACE_EVENT(2, "notoper");
1384 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1385 ccw_device_set_timeout(cdev, 0);
1386 cio_disable_subchannel(sch);
1387 cdev->private->state = DEV_STATE_NOT_OPER;
1390 enum io_sch_action {
1394 IO_SCH_UNREG_ATTACH,
1402 static enum io_sch_action sch_get_action(struct subchannel *sch)
1404 struct ccw_device *cdev;
1406 cdev = sch_get_cdev(sch);
1407 if (cio_update_schib(sch)) {
1408 /* Not operational. */
1410 return IO_SCH_UNREG;
1411 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1412 return IO_SCH_UNREG;
1413 return IO_SCH_ORPH_UNREG;
1417 return IO_SCH_ATTACH;
1418 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1419 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1420 return IO_SCH_UNREG_ATTACH;
1421 return IO_SCH_ORPH_ATTACH;
1423 if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1424 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1425 return IO_SCH_UNREG;
1428 if (device_is_disconnected(cdev))
1429 return IO_SCH_REPROBE;
1430 if (cdev->online && !cdev->private->flags.resuming)
1431 return IO_SCH_VERIFY;
1432 if (cdev->private->state == DEV_STATE_NOT_OPER)
1433 return IO_SCH_UNREG_ATTACH;
1438 * io_subchannel_sch_event - process subchannel event
1440 * @process: non-zero if function is called in process context
1442 * An unspecified event occurred for this subchannel. Adjust data according
1443 * to the current operational state of the subchannel and device. Return
1444 * zero when the event has been handled sufficiently or -EAGAIN when this
1445 * function should be called again in process context.
1447 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1449 unsigned long flags;
1450 struct ccw_device *cdev;
1451 struct ccw_dev_id dev_id;
1452 enum io_sch_action action;
1455 spin_lock_irqsave(sch->lock, flags);
1456 if (!device_is_registered(&sch->dev))
1458 if (work_pending(&sch->todo_work))
1460 cdev = sch_get_cdev(sch);
1461 if (cdev && work_pending(&cdev->private->todo_work))
1463 action = sch_get_action(sch);
1464 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1465 sch->schid.ssid, sch->schid.sch_no, process,
1467 /* Perform immediate actions while holding the lock. */
1469 case IO_SCH_REPROBE:
1470 /* Trigger device recognition. */
1471 ccw_device_trigger_reprobe(cdev);
1475 /* Trigger path verification. */
1476 io_subchannel_verify(sch);
1480 ccw_device_set_disconnected(cdev);
1483 case IO_SCH_ORPH_UNREG:
1484 case IO_SCH_ORPH_ATTACH:
1485 ccw_device_set_disconnected(cdev);
1487 case IO_SCH_UNREG_ATTACH:
1491 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1493 * Note: delayed work triggered by this event
1494 * and repeated calls to sch_event are synchronized
1495 * by the above check for work_pending(cdev).
1497 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1499 ccw_device_set_notoper(cdev);
1507 spin_unlock_irqrestore(sch->lock, flags);
1508 /* All other actions require process context. */
1511 /* Handle attached ccw device. */
1513 case IO_SCH_ORPH_UNREG:
1514 case IO_SCH_ORPH_ATTACH:
1515 /* Move ccw device to orphanage. */
1516 rc = ccw_device_move_to_orph(cdev);
1520 case IO_SCH_UNREG_ATTACH:
1521 spin_lock_irqsave(sch->lock, flags);
1522 if (cdev->private->flags.resuming) {
1523 /* Device will be handled later. */
1527 sch_set_cdev(sch, NULL);
1528 spin_unlock_irqrestore(sch->lock, flags);
1529 /* Unregister ccw device. */
1530 ccw_device_unregister(cdev);
1535 /* Handle subchannel. */
1537 case IO_SCH_ORPH_UNREG:
1539 if (!cdev || !cdev->private->flags.resuming)
1540 css_sch_device_unregister(sch);
1542 case IO_SCH_ORPH_ATTACH:
1543 case IO_SCH_UNREG_ATTACH:
1545 dev_id.ssid = sch->schid.ssid;
1546 dev_id.devno = sch->schib.pmcw.dev;
1547 cdev = get_ccwdev_by_dev_id(&dev_id);
1549 sch_create_and_recog_new_device(sch);
1552 rc = ccw_device_move_to_sch(cdev, sch);
1554 /* Release reference from get_ccwdev_by_dev_id() */
1555 put_device(&cdev->dev);
1558 spin_lock_irqsave(sch->lock, flags);
1559 ccw_device_trigger_reprobe(cdev);
1560 spin_unlock_irqrestore(sch->lock, flags);
1561 /* Release reference from get_ccwdev_by_dev_id() */
1562 put_device(&cdev->dev);
1570 spin_unlock_irqrestore(sch->lock, flags);
1575 #ifdef CONFIG_CCW_CONSOLE
1576 static int ccw_device_console_enable(struct ccw_device *cdev,
1577 struct subchannel *sch)
1581 io_subchannel_init_fields(sch);
1582 rc = cio_commit_config(sch);
1585 sch->driver = &io_subchannel_driver;
1586 sch_set_cdev(sch, cdev);
1587 io_subchannel_recog(cdev, sch);
1588 /* Now wait for the async. recognition to come to an end. */
1589 spin_lock_irq(cdev->ccwlock);
1590 while (!dev_fsm_final_state(cdev))
1591 ccw_device_wait_idle(cdev);
1593 /* Hold on to an extra reference while device is online. */
1594 get_device(&cdev->dev);
1595 rc = ccw_device_online(cdev);
1599 while (!dev_fsm_final_state(cdev))
1600 ccw_device_wait_idle(cdev);
1602 if (cdev->private->state == DEV_STATE_ONLINE)
1607 spin_unlock_irq(cdev->ccwlock);
1608 if (rc) /* Give up online reference since onlining failed. */
1609 put_device(&cdev->dev);
1613 struct ccw_device *ccw_device_probe_console(void)
1615 struct io_subchannel_private *io_priv;
1616 struct ccw_device *cdev;
1617 struct subchannel *sch;
1620 sch = cio_probe_console();
1622 return ERR_CAST(sch);
1624 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1626 put_device(&sch->dev);
1627 return ERR_PTR(-ENOMEM);
1629 cdev = io_subchannel_create_ccwdev(sch);
1631 put_device(&sch->dev);
1635 set_io_private(sch, io_priv);
1636 ret = ccw_device_console_enable(cdev, sch);
1638 set_io_private(sch, NULL);
1639 put_device(&sch->dev);
1640 put_device(&cdev->dev);
1642 return ERR_PTR(ret);
1648 * ccw_device_wait_idle() - busy wait for device to become idle
1651 * Poll until activity control is zero, that is, no function or data
1652 * transfer is pending/active.
1653 * Called with device lock being held.
1655 void ccw_device_wait_idle(struct ccw_device *cdev)
1657 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1661 if (sch->schib.scsw.cmd.actl == 0)
1667 static int ccw_device_pm_restore(struct device *dev);
1669 int ccw_device_force_console(struct ccw_device *cdev)
1671 return ccw_device_pm_restore(&cdev->dev);
1673 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1677 * get ccw_device matching the busid, but only if owned by cdrv
1680 __ccwdev_check_busid(struct device *dev, void *id)
1686 return (strcmp(bus_id, dev_name(dev)) == 0);
1691 * get_ccwdev_by_busid() - obtain device from a bus id
1692 * @cdrv: driver the device is owned by
1693 * @bus_id: bus id of the device to be searched
1695 * This function searches all devices owned by @cdrv for a device with a bus
1696 * id matching @bus_id.
1698 * If a match is found, its reference count of the found device is increased
1699 * and it is returned; else %NULL is returned.
1701 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1706 dev = driver_find_device(&cdrv->driver, NULL, (void *)bus_id,
1707 __ccwdev_check_busid);
1709 return dev ? to_ccwdev(dev) : NULL;
1712 /************************** device driver handling ************************/
1714 /* This is the implementation of the ccw_driver class. The probe, remove
1715 * and release methods are initially very similar to the device_driver
1716 * implementations, with the difference that they have ccw_device
1719 * A ccw driver also contains the information that is needed for
1723 ccw_device_probe (struct device *dev)
1725 struct ccw_device *cdev = to_ccwdev(dev);
1726 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1729 cdev->drv = cdrv; /* to let the driver call _set_online */
1730 /* Note: we interpret class 0 in this context as an uninitialized
1731 * field since it translates to a non-I/O interrupt class. */
1732 if (cdrv->int_class != 0)
1733 cdev->private->int_class = cdrv->int_class;
1735 cdev->private->int_class = IRQIO_CIO;
1737 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1741 cdev->private->int_class = IRQIO_CIO;
1749 ccw_device_remove (struct device *dev)
1751 struct ccw_device *cdev = to_ccwdev(dev);
1752 struct ccw_driver *cdrv = cdev->drv;
1759 spin_lock_irq(cdev->ccwlock);
1760 ret = ccw_device_offline(cdev);
1761 spin_unlock_irq(cdev->ccwlock);
1763 wait_event(cdev->private->wait_q,
1764 dev_fsm_final_state(cdev));
1766 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1767 "device 0.%x.%04x\n",
1768 ret, cdev->private->dev_id.ssid,
1769 cdev->private->dev_id.devno);
1770 /* Give up reference obtained in ccw_device_set_online(). */
1771 put_device(&cdev->dev);
1773 ccw_device_set_timeout(cdev, 0);
1775 cdev->private->int_class = IRQIO_CIO;
1779 static void ccw_device_shutdown(struct device *dev)
1781 struct ccw_device *cdev;
1783 cdev = to_ccwdev(dev);
1784 if (cdev->drv && cdev->drv->shutdown)
1785 cdev->drv->shutdown(cdev);
1789 static int ccw_device_pm_prepare(struct device *dev)
1791 struct ccw_device *cdev = to_ccwdev(dev);
1793 if (work_pending(&cdev->private->todo_work))
1795 /* Fail while device is being set online/offline. */
1796 if (atomic_read(&cdev->private->onoff))
1799 if (cdev->online && cdev->drv && cdev->drv->prepare)
1800 return cdev->drv->prepare(cdev);
1805 static void ccw_device_pm_complete(struct device *dev)
1807 struct ccw_device *cdev = to_ccwdev(dev);
1809 if (cdev->online && cdev->drv && cdev->drv->complete)
1810 cdev->drv->complete(cdev);
1813 static int ccw_device_pm_freeze(struct device *dev)
1815 struct ccw_device *cdev = to_ccwdev(dev);
1816 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1817 int ret, cm_enabled;
1819 /* Fail suspend while device is in transistional state. */
1820 if (!dev_fsm_final_state(cdev))
1824 if (cdev->drv && cdev->drv->freeze) {
1825 ret = cdev->drv->freeze(cdev);
1830 spin_lock_irq(sch->lock);
1831 cm_enabled = cdev->private->cmb != NULL;
1832 spin_unlock_irq(sch->lock);
1834 /* Don't have the css write on memory. */
1835 ret = ccw_set_cmf(cdev, 0);
1839 /* From here on, disallow device driver I/O. */
1840 spin_lock_irq(sch->lock);
1841 ret = cio_disable_subchannel(sch);
1842 spin_unlock_irq(sch->lock);
1847 static int ccw_device_pm_thaw(struct device *dev)
1849 struct ccw_device *cdev = to_ccwdev(dev);
1850 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1851 int ret, cm_enabled;
1856 spin_lock_irq(sch->lock);
1857 /* Allow device driver I/O again. */
1858 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1859 cm_enabled = cdev->private->cmb != NULL;
1860 spin_unlock_irq(sch->lock);
1865 ret = ccw_set_cmf(cdev, 1);
1870 if (cdev->drv && cdev->drv->thaw)
1871 ret = cdev->drv->thaw(cdev);
1876 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1878 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1880 spin_lock_irq(sch->lock);
1881 if (cio_is_console(sch->schid)) {
1882 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1886 * While we were sleeping, devices may have gone or become
1887 * available again. Kick re-detection.
1889 cdev->private->flags.resuming = 1;
1890 cdev->private->path_new_mask = LPM_ANYPATH;
1891 css_sched_sch_todo(sch, SCH_TODO_EVAL);
1892 spin_unlock_irq(sch->lock);
1893 css_wait_for_slow_path();
1895 /* cdev may have been moved to a different subchannel. */
1896 sch = to_subchannel(cdev->dev.parent);
1897 spin_lock_irq(sch->lock);
1898 if (cdev->private->state != DEV_STATE_ONLINE &&
1899 cdev->private->state != DEV_STATE_OFFLINE)
1902 ccw_device_recognition(cdev);
1903 spin_unlock_irq(sch->lock);
1904 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1905 cdev->private->state == DEV_STATE_DISCONNECTED);
1906 spin_lock_irq(sch->lock);
1909 cdev->private->flags.resuming = 0;
1910 spin_unlock_irq(sch->lock);
1913 static int resume_handle_boxed(struct ccw_device *cdev)
1915 cdev->private->state = DEV_STATE_BOXED;
1916 if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1918 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1922 static int resume_handle_disc(struct ccw_device *cdev)
1924 cdev->private->state = DEV_STATE_DISCONNECTED;
1925 if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1927 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1931 static int ccw_device_pm_restore(struct device *dev)
1933 struct ccw_device *cdev = to_ccwdev(dev);
1934 struct subchannel *sch;
1937 __ccw_device_pm_restore(cdev);
1938 sch = to_subchannel(cdev->dev.parent);
1939 spin_lock_irq(sch->lock);
1940 if (cio_is_console(sch->schid))
1943 /* check recognition results */
1944 switch (cdev->private->state) {
1945 case DEV_STATE_OFFLINE:
1946 case DEV_STATE_ONLINE:
1947 cdev->private->flags.donotify = 0;
1949 case DEV_STATE_BOXED:
1950 ret = resume_handle_boxed(cdev);
1955 ret = resume_handle_disc(cdev);
1960 /* check if the device type has changed */
1961 if (!ccw_device_test_sense_data(cdev)) {
1962 ccw_device_update_sense_data(cdev);
1963 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1970 if (ccw_device_online(cdev)) {
1971 ret = resume_handle_disc(cdev);
1976 spin_unlock_irq(sch->lock);
1977 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1978 spin_lock_irq(sch->lock);
1980 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1981 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1986 /* reenable cmf, if needed */
1987 if (cdev->private->cmb) {
1988 spin_unlock_irq(sch->lock);
1989 ret = ccw_set_cmf(cdev, 1);
1990 spin_lock_irq(sch->lock);
1992 CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1993 "(rc=%d)\n", cdev->private->dev_id.ssid,
1994 cdev->private->dev_id.devno, ret);
2000 spin_unlock_irq(sch->lock);
2001 if (cdev->online && cdev->drv && cdev->drv->restore)
2002 ret = cdev->drv->restore(cdev);
2006 spin_unlock_irq(sch->lock);
2010 static const struct dev_pm_ops ccw_pm_ops = {
2011 .prepare = ccw_device_pm_prepare,
2012 .complete = ccw_device_pm_complete,
2013 .freeze = ccw_device_pm_freeze,
2014 .thaw = ccw_device_pm_thaw,
2015 .restore = ccw_device_pm_restore,
2018 static struct bus_type ccw_bus_type = {
2020 .match = ccw_bus_match,
2021 .uevent = ccw_uevent,
2022 .probe = ccw_device_probe,
2023 .remove = ccw_device_remove,
2024 .shutdown = ccw_device_shutdown,
2029 * ccw_driver_register() - register a ccw driver
2030 * @cdriver: driver to be registered
2032 * This function is mainly a wrapper around driver_register().
2034 * %0 on success and a negative error value on failure.
2036 int ccw_driver_register(struct ccw_driver *cdriver)
2038 struct device_driver *drv = &cdriver->driver;
2040 drv->bus = &ccw_bus_type;
2042 return driver_register(drv);
2046 * ccw_driver_unregister() - deregister a ccw driver
2047 * @cdriver: driver to be deregistered
2049 * This function is mainly a wrapper around driver_unregister().
2051 void ccw_driver_unregister(struct ccw_driver *cdriver)
2053 driver_unregister(&cdriver->driver);
2056 static void ccw_device_todo(struct work_struct *work)
2058 struct ccw_device_private *priv;
2059 struct ccw_device *cdev;
2060 struct subchannel *sch;
2061 enum cdev_todo todo;
2063 priv = container_of(work, struct ccw_device_private, todo_work);
2065 sch = to_subchannel(cdev->dev.parent);
2066 /* Find out todo. */
2067 spin_lock_irq(cdev->ccwlock);
2069 priv->todo = CDEV_TODO_NOTHING;
2070 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2071 priv->dev_id.ssid, priv->dev_id.devno, todo);
2072 spin_unlock_irq(cdev->ccwlock);
2075 case CDEV_TODO_ENABLE_CMF:
2078 case CDEV_TODO_REBIND:
2079 ccw_device_do_unbind_bind(cdev);
2081 case CDEV_TODO_REGISTER:
2082 io_subchannel_register(cdev);
2084 case CDEV_TODO_UNREG_EVAL:
2085 if (!sch_is_pseudo_sch(sch))
2086 css_schedule_eval(sch->schid);
2088 case CDEV_TODO_UNREG:
2089 if (sch_is_pseudo_sch(sch))
2090 ccw_device_unregister(cdev);
2092 ccw_device_call_sch_unregister(cdev);
2097 /* Release workqueue ref. */
2098 put_device(&cdev->dev);
2102 * ccw_device_sched_todo - schedule ccw device operation
2106 * Schedule the operation identified by @todo to be performed on the slow path
2107 * workqueue. Do nothing if another operation with higher priority is already
2108 * scheduled. Needs to be called with ccwdev lock held.
2110 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2112 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2113 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2115 if (cdev->private->todo >= todo)
2117 cdev->private->todo = todo;
2118 /* Get workqueue ref. */
2119 if (!get_device(&cdev->dev))
2121 if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2122 /* Already queued, release workqueue ref. */
2123 put_device(&cdev->dev);
2128 * ccw_device_siosl() - initiate logging
2131 * This function is used to invoke model-dependent logging within the channel
2134 int ccw_device_siosl(struct ccw_device *cdev)
2136 struct subchannel *sch = to_subchannel(cdev->dev.parent);
2138 return chsc_siosl(sch->schid);
2140 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2142 MODULE_LICENSE("GPL");
2143 EXPORT_SYMBOL(ccw_device_set_online);
2144 EXPORT_SYMBOL(ccw_device_set_offline);
2145 EXPORT_SYMBOL(ccw_driver_register);
2146 EXPORT_SYMBOL(ccw_driver_unregister);
2147 EXPORT_SYMBOL(get_ccwdev_by_busid);