1 // SPDX-License-Identifier: GPL-1.0+
3 * bus driver for ccw devices
5 * Copyright IBM Corp. 2002, 2008
6 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
7 * Cornelia Huck (cornelia.huck@de.ibm.com)
8 * Martin Schwidefsky (schwidefsky@de.ibm.com)
11 #define KMSG_COMPONENT "cio"
12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14 #include <linux/export.h>
15 #include <linux/init.h>
16 #include <linux/spinlock.h>
17 #include <linux/errno.h>
18 #include <linux/err.h>
19 #include <linux/slab.h>
20 #include <linux/list.h>
21 #include <linux/device.h>
22 #include <linux/workqueue.h>
23 #include <linux/delay.h>
24 #include <linux/timer.h>
25 #include <linux/kernel_stat.h>
26 #include <linux/sched/signal.h>
27 #include <linux/dma-mapping.h>
29 #include <asm/ccwdev.h>
31 #include <asm/param.h> /* HZ */
37 #include "cio_debug.h"
42 #include "blacklist.h"
45 static struct timer_list recovery_timer;
46 static DEFINE_SPINLOCK(recovery_lock);
47 static int recovery_phase;
48 static const unsigned long recovery_delay[] = { 3, 30, 300 };
50 static atomic_t ccw_device_init_count = ATOMIC_INIT(0);
51 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq);
52 static struct bus_type ccw_bus_type;
54 /******************* bus type handling ***********************/
56 /* The Linux driver model distinguishes between a bus type and
57 * the bus itself. Of course we only have one channel
58 * subsystem driver and one channel system per machine, but
59 * we still use the abstraction. T.R. says it's a good idea. */
61 ccw_bus_match (struct device * dev, struct device_driver * drv)
63 struct ccw_device *cdev = to_ccwdev(dev);
64 struct ccw_driver *cdrv = to_ccwdrv(drv);
65 const struct ccw_device_id *ids = cdrv->ids, *found;
70 found = ccw_device_id_match(ids, &cdev->id);
74 cdev->id.driver_info = found->driver_info;
79 /* Store modalias string delimited by prefix/suffix string into buffer with
80 * specified size. Return length of resulting string (excluding trailing '\0')
81 * even if string doesn't fit buffer (snprintf semantics). */
82 static int snprint_alias(char *buf, size_t size,
83 struct ccw_device_id *id, const char *suffix)
87 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
93 if (id->dev_type != 0)
94 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
95 id->dev_model, suffix);
97 len += snprintf(buf, size, "dtdm%s", suffix);
102 /* Set up environment variables for ccw device uevent. Return 0 on success,
103 * non-zero otherwise. */
104 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
106 struct ccw_device *cdev = to_ccwdev(dev);
107 struct ccw_device_id *id = &(cdev->id);
109 char modalias_buf[30];
112 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
117 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
121 /* The next two can be zero, that's ok for us */
123 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
128 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
133 snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
134 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
138 static void io_subchannel_irq(struct subchannel *);
139 static int io_subchannel_probe(struct subchannel *);
140 static int io_subchannel_remove(struct subchannel *);
141 static void io_subchannel_shutdown(struct subchannel *);
142 static int io_subchannel_sch_event(struct subchannel *, int);
143 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
145 static void recovery_func(struct timer_list *unused);
147 static struct css_device_id io_subchannel_ids[] = {
148 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
149 { /* end of list */ },
152 static int io_subchannel_prepare(struct subchannel *sch)
154 struct ccw_device *cdev;
156 * Don't allow suspend while a ccw device registration
157 * is still outstanding.
159 cdev = sch_get_cdev(sch);
160 if (cdev && !device_is_registered(&cdev->dev))
165 static int io_subchannel_settle(void)
169 ret = wait_event_interruptible(ccw_device_init_wq,
170 atomic_read(&ccw_device_init_count) == 0);
173 flush_workqueue(cio_work_q);
177 static struct css_driver io_subchannel_driver = {
179 .owner = THIS_MODULE,
180 .name = "io_subchannel",
182 .subchannel_type = io_subchannel_ids,
183 .irq = io_subchannel_irq,
184 .sch_event = io_subchannel_sch_event,
185 .chp_event = io_subchannel_chp_event,
186 .probe = io_subchannel_probe,
187 .remove = io_subchannel_remove,
188 .shutdown = io_subchannel_shutdown,
189 .prepare = io_subchannel_prepare,
190 .settle = io_subchannel_settle,
193 int __init io_subchannel_init(void)
197 timer_setup(&recovery_timer, recovery_func, 0);
198 ret = bus_register(&ccw_bus_type);
201 ret = css_driver_register(&io_subchannel_driver);
203 bus_unregister(&ccw_bus_type);
209 /************************ device handling **************************/
212 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
214 struct ccw_device *cdev = to_ccwdev(dev);
215 struct ccw_device_id *id = &(cdev->id);
217 if (id->dev_type != 0)
218 return sprintf(buf, "%04x/%02x\n",
219 id->dev_type, id->dev_model);
221 return sprintf(buf, "n/a\n");
225 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
227 struct ccw_device *cdev = to_ccwdev(dev);
228 struct ccw_device_id *id = &(cdev->id);
230 return sprintf(buf, "%04x/%02x\n",
231 id->cu_type, id->cu_model);
235 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
237 struct ccw_device *cdev = to_ccwdev(dev);
238 struct ccw_device_id *id = &(cdev->id);
241 len = snprint_alias(buf, PAGE_SIZE, id, "\n");
243 return len > PAGE_SIZE ? PAGE_SIZE : len;
247 online_show (struct device *dev, struct device_attribute *attr, char *buf)
249 struct ccw_device *cdev = to_ccwdev(dev);
251 return sprintf(buf, cdev->online ? "1\n" : "0\n");
254 int ccw_device_is_orphan(struct ccw_device *cdev)
256 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
259 static void ccw_device_unregister(struct ccw_device *cdev)
261 if (device_is_registered(&cdev->dev)) {
262 /* Undo device_add(). */
263 device_del(&cdev->dev);
265 if (cdev->private->flags.initialized) {
266 cdev->private->flags.initialized = 0;
267 /* Release reference from device_initialize(). */
268 put_device(&cdev->dev);
272 static void io_subchannel_quiesce(struct subchannel *);
275 * ccw_device_set_offline() - disable a ccw device for I/O
276 * @cdev: target ccw device
278 * This function calls the driver's set_offline() function for @cdev, if
279 * given, and then disables @cdev.
281 * %0 on success and a negative error value on failure.
283 * enabled, ccw device lock not held
285 int ccw_device_set_offline(struct ccw_device *cdev)
287 struct subchannel *sch;
292 if (!cdev->online || !cdev->drv)
295 if (cdev->drv->set_offline) {
296 ret = cdev->drv->set_offline(cdev);
300 spin_lock_irq(cdev->ccwlock);
301 sch = to_subchannel(cdev->dev.parent);
303 /* Wait until a final state or DISCONNECTED is reached */
304 while (!dev_fsm_final_state(cdev) &&
305 cdev->private->state != DEV_STATE_DISCONNECTED) {
306 spin_unlock_irq(cdev->ccwlock);
307 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
308 cdev->private->state == DEV_STATE_DISCONNECTED));
309 spin_lock_irq(cdev->ccwlock);
312 ret = ccw_device_offline(cdev);
315 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
316 "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
317 cdev->private->dev_id.devno);
320 state = cdev->private->state;
321 spin_unlock_irq(cdev->ccwlock);
322 io_subchannel_quiesce(sch);
323 spin_lock_irq(cdev->ccwlock);
324 cdev->private->state = state;
325 } while (ret == -EBUSY);
326 spin_unlock_irq(cdev->ccwlock);
327 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
328 cdev->private->state == DEV_STATE_DISCONNECTED));
329 /* Inform the user if set offline failed. */
330 if (cdev->private->state == DEV_STATE_BOXED) {
331 pr_warn("%s: The device entered boxed state while being set offline\n",
332 dev_name(&cdev->dev));
333 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
334 pr_warn("%s: The device stopped operating while being set offline\n",
335 dev_name(&cdev->dev));
337 /* Give up reference from ccw_device_set_online(). */
338 put_device(&cdev->dev);
342 cdev->private->state = DEV_STATE_OFFLINE;
343 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
344 spin_unlock_irq(cdev->ccwlock);
345 /* Give up reference from ccw_device_set_online(). */
346 put_device(&cdev->dev);
351 * ccw_device_set_online() - enable a ccw device for I/O
352 * @cdev: target ccw device
354 * This function first enables @cdev and then calls the driver's set_online()
355 * function for @cdev, if given. If set_online() returns an error, @cdev is
358 * %0 on success and a negative error value on failure.
360 * enabled, ccw device lock not held
362 int ccw_device_set_online(struct ccw_device *cdev)
369 if (cdev->online || !cdev->drv)
371 /* Hold on to an extra reference while device is online. */
372 if (!get_device(&cdev->dev))
375 spin_lock_irq(cdev->ccwlock);
376 ret = ccw_device_online(cdev);
377 spin_unlock_irq(cdev->ccwlock);
379 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
381 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
382 "device 0.%x.%04x\n",
383 ret, cdev->private->dev_id.ssid,
384 cdev->private->dev_id.devno);
385 /* Give up online reference since onlining failed. */
386 put_device(&cdev->dev);
389 spin_lock_irq(cdev->ccwlock);
390 /* Check if online processing was successful */
391 if ((cdev->private->state != DEV_STATE_ONLINE) &&
392 (cdev->private->state != DEV_STATE_W4SENSE)) {
393 spin_unlock_irq(cdev->ccwlock);
394 /* Inform the user that set online failed. */
395 if (cdev->private->state == DEV_STATE_BOXED) {
396 pr_warn("%s: Setting the device online failed because it is boxed\n",
397 dev_name(&cdev->dev));
398 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
399 pr_warn("%s: Setting the device online failed because it is not operational\n",
400 dev_name(&cdev->dev));
402 /* Give up online reference since onlining failed. */
403 put_device(&cdev->dev);
406 spin_unlock_irq(cdev->ccwlock);
407 if (cdev->drv->set_online)
408 ret = cdev->drv->set_online(cdev);
412 spin_lock_irq(cdev->ccwlock);
414 spin_unlock_irq(cdev->ccwlock);
418 spin_lock_irq(cdev->ccwlock);
419 /* Wait until a final state or DISCONNECTED is reached */
420 while (!dev_fsm_final_state(cdev) &&
421 cdev->private->state != DEV_STATE_DISCONNECTED) {
422 spin_unlock_irq(cdev->ccwlock);
423 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
424 cdev->private->state == DEV_STATE_DISCONNECTED));
425 spin_lock_irq(cdev->ccwlock);
427 ret2 = ccw_device_offline(cdev);
430 spin_unlock_irq(cdev->ccwlock);
431 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
432 cdev->private->state == DEV_STATE_DISCONNECTED));
433 /* Give up online reference since onlining failed. */
434 put_device(&cdev->dev);
438 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
439 "device 0.%x.%04x\n",
440 ret2, cdev->private->dev_id.ssid,
441 cdev->private->dev_id.devno);
442 cdev->private->state = DEV_STATE_OFFLINE;
443 spin_unlock_irq(cdev->ccwlock);
444 /* Give up online reference since onlining failed. */
445 put_device(&cdev->dev);
449 static int online_store_handle_offline(struct ccw_device *cdev)
451 if (cdev->private->state == DEV_STATE_DISCONNECTED) {
452 spin_lock_irq(cdev->ccwlock);
453 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
454 spin_unlock_irq(cdev->ccwlock);
457 if (cdev->drv && cdev->drv->set_offline)
458 return ccw_device_set_offline(cdev);
462 static int online_store_recog_and_online(struct ccw_device *cdev)
464 /* Do device recognition, if needed. */
465 if (cdev->private->state == DEV_STATE_BOXED) {
466 spin_lock_irq(cdev->ccwlock);
467 ccw_device_recognition(cdev);
468 spin_unlock_irq(cdev->ccwlock);
469 wait_event(cdev->private->wait_q,
470 cdev->private->flags.recog_done);
471 if (cdev->private->state != DEV_STATE_OFFLINE)
472 /* recognition failed */
475 if (cdev->drv && cdev->drv->set_online)
476 return ccw_device_set_online(cdev);
480 static int online_store_handle_online(struct ccw_device *cdev, int force)
484 ret = online_store_recog_and_online(cdev);
487 if (force && cdev->private->state == DEV_STATE_BOXED) {
488 ret = ccw_device_stlck(cdev);
491 if (cdev->id.cu_type == 0)
492 cdev->private->state = DEV_STATE_NOT_OPER;
493 ret = online_store_recog_and_online(cdev);
500 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
501 const char *buf, size_t count)
503 struct ccw_device *cdev = to_ccwdev(dev);
507 /* Prevent conflict between multiple on-/offline processing requests. */
508 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
510 /* Prevent conflict between internal I/Os and on-/offline processing. */
511 if (!dev_fsm_final_state(cdev) &&
512 cdev->private->state != DEV_STATE_DISCONNECTED) {
516 /* Prevent conflict between pending work and on-/offline processing.*/
517 if (work_pending(&cdev->private->todo_work)) {
521 if (!strncmp(buf, "force\n", count)) {
527 ret = kstrtoul(buf, 16, &i);
535 ret = online_store_handle_offline(cdev);
538 ret = online_store_handle_online(cdev, force);
546 atomic_set(&cdev->private->onoff, 0);
547 return (ret < 0) ? ret : count;
551 available_show (struct device *dev, struct device_attribute *attr, char *buf)
553 struct ccw_device *cdev = to_ccwdev(dev);
554 struct subchannel *sch;
556 if (ccw_device_is_orphan(cdev))
557 return sprintf(buf, "no device\n");
558 switch (cdev->private->state) {
559 case DEV_STATE_BOXED:
560 return sprintf(buf, "boxed\n");
561 case DEV_STATE_DISCONNECTED:
562 case DEV_STATE_DISCONNECTED_SENSE_ID:
563 case DEV_STATE_NOT_OPER:
564 sch = to_subchannel(dev->parent);
566 return sprintf(buf, "no path\n");
568 return sprintf(buf, "no device\n");
570 /* All other states considered fine. */
571 return sprintf(buf, "good\n");
576 initiate_logging(struct device *dev, struct device_attribute *attr,
577 const char *buf, size_t count)
579 struct subchannel *sch = to_subchannel(dev);
582 rc = chsc_siosl(sch->schid);
584 pr_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n",
585 sch->schid.ssid, sch->schid.sch_no, rc);
588 pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
589 sch->schid.ssid, sch->schid.sch_no);
593 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr,
596 struct subchannel *sch = to_subchannel(dev);
598 return sprintf(buf, "%02x\n", sch->vpm);
601 static DEVICE_ATTR_RO(devtype);
602 static DEVICE_ATTR_RO(cutype);
603 static DEVICE_ATTR_RO(modalias);
604 static DEVICE_ATTR_RW(online);
605 static DEVICE_ATTR(availability, 0444, available_show, NULL);
606 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
607 static DEVICE_ATTR_RO(vpm);
609 static struct attribute *io_subchannel_attrs[] = {
610 &dev_attr_logging.attr,
615 static const struct attribute_group io_subchannel_attr_group = {
616 .attrs = io_subchannel_attrs,
619 static struct attribute * ccwdev_attrs[] = {
620 &dev_attr_devtype.attr,
621 &dev_attr_cutype.attr,
622 &dev_attr_modalias.attr,
623 &dev_attr_online.attr,
624 &dev_attr_cmb_enable.attr,
625 &dev_attr_availability.attr,
629 static const struct attribute_group ccwdev_attr_group = {
630 .attrs = ccwdev_attrs,
633 static const struct attribute_group *ccwdev_attr_groups[] = {
638 static int ccw_device_add(struct ccw_device *cdev)
640 struct device *dev = &cdev->dev;
642 dev->bus = &ccw_bus_type;
643 return device_add(dev);
646 static int match_dev_id(struct device *dev, const void *data)
648 struct ccw_device *cdev = to_ccwdev(dev);
649 struct ccw_dev_id *dev_id = (void *)data;
651 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
655 * get_ccwdev_by_dev_id() - obtain device from a ccw device id
656 * @dev_id: id of the device to be searched
658 * This function searches all devices attached to the ccw bus for a device
661 * If a device is found its reference count is increased and returned;
662 * else %NULL is returned.
664 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
668 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
670 return dev ? to_ccwdev(dev) : NULL;
672 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id);
674 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
678 if (device_is_registered(&cdev->dev)) {
679 device_release_driver(&cdev->dev);
680 ret = device_attach(&cdev->dev);
681 WARN_ON(ret == -ENODEV);
686 ccw_device_release(struct device *dev)
688 struct ccw_device *cdev;
690 cdev = to_ccwdev(dev);
691 cio_gp_dma_free(cdev->private->dma_pool, cdev->private->dma_area,
692 sizeof(*cdev->private->dma_area));
693 cio_gp_dma_destroy(cdev->private->dma_pool, &cdev->dev);
694 /* Release reference of parent subchannel. */
695 put_device(cdev->dev.parent);
696 kfree(cdev->private);
700 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
702 struct ccw_device *cdev;
703 struct gen_pool *dma_pool;
705 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
708 cdev->private = kzalloc(sizeof(struct ccw_device_private),
709 GFP_KERNEL | GFP_DMA);
712 cdev->dev.coherent_dma_mask = sch->dev.coherent_dma_mask;
713 cdev->dev.dma_mask = sch->dev.dma_mask;
714 dma_pool = cio_gp_dma_create(&cdev->dev, 1);
717 cdev->private->dma_pool = dma_pool;
718 cdev->private->dma_area = cio_gp_dma_zalloc(dma_pool, &cdev->dev,
719 sizeof(*cdev->private->dma_area));
720 if (!cdev->private->dma_area)
724 cio_gp_dma_destroy(dma_pool, &cdev->dev);
726 kfree(cdev->private);
730 return ERR_PTR(-ENOMEM);
733 static void ccw_device_todo(struct work_struct *work);
735 static int io_subchannel_initialize_dev(struct subchannel *sch,
736 struct ccw_device *cdev)
738 struct ccw_device_private *priv = cdev->private;
742 priv->int_class = IRQIO_CIO;
743 priv->state = DEV_STATE_NOT_OPER;
744 priv->dev_id.devno = sch->schib.pmcw.dev;
745 priv->dev_id.ssid = sch->schid.ssid;
747 INIT_WORK(&priv->todo_work, ccw_device_todo);
748 INIT_LIST_HEAD(&priv->cmb_list);
749 init_waitqueue_head(&priv->wait_q);
750 timer_setup(&priv->timer, ccw_device_timeout, 0);
752 atomic_set(&priv->onoff, 0);
753 cdev->ccwlock = sch->lock;
754 cdev->dev.parent = &sch->dev;
755 cdev->dev.release = ccw_device_release;
756 cdev->dev.groups = ccwdev_attr_groups;
757 /* Do first half of device_register. */
758 device_initialize(&cdev->dev);
759 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
760 cdev->private->dev_id.devno);
763 if (!get_device(&sch->dev)) {
767 priv->flags.initialized = 1;
768 spin_lock_irq(sch->lock);
769 sch_set_cdev(sch, cdev);
770 spin_unlock_irq(sch->lock);
774 /* Release reference from device_initialize(). */
775 put_device(&cdev->dev);
779 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
781 struct ccw_device *cdev;
784 cdev = io_subchannel_allocate_dev(sch);
786 ret = io_subchannel_initialize_dev(sch, cdev);
793 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
795 static void sch_create_and_recog_new_device(struct subchannel *sch)
797 struct ccw_device *cdev;
799 /* Need to allocate a new ccw device. */
800 cdev = io_subchannel_create_ccwdev(sch);
802 /* OK, we did everything we could... */
803 css_sch_device_unregister(sch);
806 /* Start recognition for the new ccw device. */
807 io_subchannel_recog(cdev, sch);
811 * Register recognized device.
813 static void io_subchannel_register(struct ccw_device *cdev)
815 struct subchannel *sch;
816 int ret, adjust_init_count = 1;
819 sch = to_subchannel(cdev->dev.parent);
821 * Check if subchannel is still registered. It may have become
822 * unregistered if a machine check hit us after finishing
823 * device recognition but before the register work could be
826 if (!device_is_registered(&sch->dev))
828 css_update_ssd_info(sch);
830 * io_subchannel_register() will also be called after device
831 * recognition has been done for a boxed device (which will already
832 * be registered). We need to reprobe since we may now have sense id
835 if (device_is_registered(&cdev->dev)) {
837 ret = device_reprobe(&cdev->dev);
839 /* We can't do much here. */
840 CIO_MSG_EVENT(0, "device_reprobe() returned"
841 " %d for 0.%x.%04x\n", ret,
842 cdev->private->dev_id.ssid,
843 cdev->private->dev_id.devno);
845 adjust_init_count = 0;
849 * Now we know this subchannel will stay, we can throw
850 * our delayed uevent.
852 if (dev_get_uevent_suppress(&sch->dev)) {
853 dev_set_uevent_suppress(&sch->dev, 0);
854 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
856 /* make it known to the system */
857 ret = ccw_device_add(cdev);
859 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
860 cdev->private->dev_id.ssid,
861 cdev->private->dev_id.devno, ret);
862 spin_lock_irqsave(sch->lock, flags);
863 sch_set_cdev(sch, NULL);
864 spin_unlock_irqrestore(sch->lock, flags);
865 /* Release initial device reference. */
866 put_device(&cdev->dev);
870 cdev->private->flags.recog_done = 1;
871 wake_up(&cdev->private->wait_q);
873 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
874 wake_up(&ccw_device_init_wq);
877 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
879 struct subchannel *sch;
881 /* Get subchannel reference for local processing. */
882 if (!get_device(cdev->dev.parent))
884 sch = to_subchannel(cdev->dev.parent);
885 css_sch_device_unregister(sch);
886 /* Release subchannel reference for local processing. */
887 put_device(&sch->dev);
891 * subchannel recognition done. Called from the state machine.
894 io_subchannel_recog_done(struct ccw_device *cdev)
896 if (css_init_done == 0) {
897 cdev->private->flags.recog_done = 1;
900 switch (cdev->private->state) {
901 case DEV_STATE_BOXED:
902 /* Device did not respond in time. */
903 case DEV_STATE_NOT_OPER:
904 cdev->private->flags.recog_done = 1;
905 /* Remove device found not operational. */
906 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
907 if (atomic_dec_and_test(&ccw_device_init_count))
908 wake_up(&ccw_device_init_wq);
910 case DEV_STATE_OFFLINE:
912 * We can't register the device in interrupt context so
913 * we schedule a work item.
915 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
920 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
922 /* Increase counter of devices currently in recognition. */
923 atomic_inc(&ccw_device_init_count);
925 /* Start async. device sensing. */
926 spin_lock_irq(sch->lock);
927 ccw_device_recognition(cdev);
928 spin_unlock_irq(sch->lock);
931 static int ccw_device_move_to_sch(struct ccw_device *cdev,
932 struct subchannel *sch)
934 struct subchannel *old_sch;
935 int rc, old_enabled = 0;
937 old_sch = to_subchannel(cdev->dev.parent);
938 /* Obtain child reference for new parent. */
939 if (!get_device(&sch->dev))
942 if (!sch_is_pseudo_sch(old_sch)) {
943 spin_lock_irq(old_sch->lock);
944 old_enabled = old_sch->schib.pmcw.ena;
947 rc = cio_disable_subchannel(old_sch);
948 spin_unlock_irq(old_sch->lock);
950 /* Release child reference for new parent. */
951 put_device(&sch->dev);
956 mutex_lock(&sch->reg_mutex);
957 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
958 mutex_unlock(&sch->reg_mutex);
960 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
961 cdev->private->dev_id.ssid,
962 cdev->private->dev_id.devno, sch->schid.ssid,
963 sch->schib.pmcw.dev, rc);
965 /* Try to reenable the old subchannel. */
966 spin_lock_irq(old_sch->lock);
967 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
968 spin_unlock_irq(old_sch->lock);
970 /* Release child reference for new parent. */
971 put_device(&sch->dev);
974 /* Clean up old subchannel. */
975 if (!sch_is_pseudo_sch(old_sch)) {
976 spin_lock_irq(old_sch->lock);
977 sch_set_cdev(old_sch, NULL);
978 spin_unlock_irq(old_sch->lock);
979 css_schedule_eval(old_sch->schid);
981 /* Release child reference for old parent. */
982 put_device(&old_sch->dev);
983 /* Initialize new subchannel. */
984 spin_lock_irq(sch->lock);
985 cdev->ccwlock = sch->lock;
986 if (!sch_is_pseudo_sch(sch))
987 sch_set_cdev(sch, cdev);
988 spin_unlock_irq(sch->lock);
989 if (!sch_is_pseudo_sch(sch))
990 css_update_ssd_info(sch);
994 static int ccw_device_move_to_orph(struct ccw_device *cdev)
996 struct subchannel *sch = to_subchannel(cdev->dev.parent);
997 struct channel_subsystem *css = to_css(sch->dev.parent);
999 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1002 static void io_subchannel_irq(struct subchannel *sch)
1004 struct ccw_device *cdev;
1006 cdev = sch_get_cdev(sch);
1008 CIO_TRACE_EVENT(6, "IRQ");
1009 CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1011 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1013 inc_irq_stat(IRQIO_CIO);
1016 void io_subchannel_init_config(struct subchannel *sch)
1018 memset(&sch->config, 0, sizeof(sch->config));
1019 sch->config.csense = 1;
1022 static void io_subchannel_init_fields(struct subchannel *sch)
1024 if (cio_is_console(sch->schid))
1027 sch->opm = chp_get_sch_opm(sch);
1028 sch->lpm = sch->schib.pmcw.pam & sch->opm;
1029 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1031 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1032 " - PIM = %02X, PAM = %02X, POM = %02X\n",
1033 sch->schib.pmcw.dev, sch->schid.ssid,
1034 sch->schid.sch_no, sch->schib.pmcw.pim,
1035 sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1037 io_subchannel_init_config(sch);
1041 * Note: We always return 0 so that we bind to the device even on error.
1042 * This is needed so that our remove function is called on unregister.
1044 static int io_subchannel_probe(struct subchannel *sch)
1046 struct io_subchannel_private *io_priv;
1047 struct ccw_device *cdev;
1050 if (cio_is_console(sch->schid)) {
1051 rc = sysfs_create_group(&sch->dev.kobj,
1052 &io_subchannel_attr_group);
1054 CIO_MSG_EVENT(0, "Failed to create io subchannel "
1055 "attributes for subchannel "
1056 "0.%x.%04x (rc=%d)\n",
1057 sch->schid.ssid, sch->schid.sch_no, rc);
1059 * The console subchannel already has an associated ccw_device.
1060 * Throw the delayed uevent for the subchannel, register
1061 * the ccw_device and exit.
1063 if (dev_get_uevent_suppress(&sch->dev)) {
1064 /* should always be the case for the console */
1065 dev_set_uevent_suppress(&sch->dev, 0);
1066 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1068 cdev = sch_get_cdev(sch);
1069 rc = ccw_device_add(cdev);
1071 /* Release online reference. */
1072 put_device(&cdev->dev);
1075 if (atomic_dec_and_test(&ccw_device_init_count))
1076 wake_up(&ccw_device_init_wq);
1079 io_subchannel_init_fields(sch);
1080 rc = cio_commit_config(sch);
1083 rc = sysfs_create_group(&sch->dev.kobj,
1084 &io_subchannel_attr_group);
1087 /* Allocate I/O subchannel private data. */
1088 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1092 io_priv->dma_area = dma_alloc_coherent(&sch->dev,
1093 sizeof(*io_priv->dma_area),
1094 &io_priv->dma_area_dma, GFP_KERNEL);
1095 if (!io_priv->dma_area) {
1100 set_io_private(sch, io_priv);
1101 css_schedule_eval(sch->schid);
1105 spin_lock_irq(sch->lock);
1106 css_sched_sch_todo(sch, SCH_TODO_UNREG);
1107 spin_unlock_irq(sch->lock);
1111 static int io_subchannel_remove(struct subchannel *sch)
1113 struct io_subchannel_private *io_priv = to_io_private(sch);
1114 struct ccw_device *cdev;
1116 cdev = sch_get_cdev(sch);
1120 ccw_device_unregister(cdev);
1121 spin_lock_irq(sch->lock);
1122 sch_set_cdev(sch, NULL);
1123 set_io_private(sch, NULL);
1124 spin_unlock_irq(sch->lock);
1126 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area),
1127 io_priv->dma_area, io_priv->dma_area_dma);
1129 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1133 static void io_subchannel_verify(struct subchannel *sch)
1135 struct ccw_device *cdev;
1137 cdev = sch_get_cdev(sch);
1139 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1142 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1144 struct ccw_device *cdev;
1146 cdev = sch_get_cdev(sch);
1149 if (cio_update_schib(sch))
1151 /* Check for I/O on path. */
1152 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1154 if (cdev->private->state == DEV_STATE_ONLINE) {
1155 ccw_device_kill_io(cdev);
1161 /* Trigger path verification. */
1162 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1166 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1169 static int io_subchannel_chp_event(struct subchannel *sch,
1170 struct chp_link *link, int event)
1172 struct ccw_device *cdev = sch_get_cdev(sch);
1175 mask = chp_ssd_get_mask(&sch->ssd_info, link);
1183 cdev->private->path_gone_mask |= mask;
1184 io_subchannel_terminate_path(sch, mask);
1190 cdev->private->path_new_mask |= mask;
1191 io_subchannel_verify(sch);
1194 if (cio_update_schib(sch))
1197 cdev->private->path_gone_mask |= mask;
1198 io_subchannel_terminate_path(sch, mask);
1201 if (cio_update_schib(sch))
1203 sch->lpm |= mask & sch->opm;
1205 cdev->private->path_new_mask |= mask;
1206 io_subchannel_verify(sch);
1212 static void io_subchannel_quiesce(struct subchannel *sch)
1214 struct ccw_device *cdev;
1217 spin_lock_irq(sch->lock);
1218 cdev = sch_get_cdev(sch);
1219 if (cio_is_console(sch->schid))
1221 if (!sch->schib.pmcw.ena)
1223 ret = cio_disable_subchannel(sch);
1227 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1228 while (ret == -EBUSY) {
1229 cdev->private->state = DEV_STATE_QUIESCE;
1230 cdev->private->iretry = 255;
1231 ret = ccw_device_cancel_halt_clear(cdev);
1232 if (ret == -EBUSY) {
1233 ccw_device_set_timeout(cdev, HZ/10);
1234 spin_unlock_irq(sch->lock);
1235 wait_event(cdev->private->wait_q,
1236 cdev->private->state != DEV_STATE_QUIESCE);
1237 spin_lock_irq(sch->lock);
1239 ret = cio_disable_subchannel(sch);
1242 spin_unlock_irq(sch->lock);
1245 static void io_subchannel_shutdown(struct subchannel *sch)
1247 io_subchannel_quiesce(sch);
1250 static int device_is_disconnected(struct ccw_device *cdev)
1254 return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1255 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1258 static int recovery_check(struct device *dev, void *data)
1260 struct ccw_device *cdev = to_ccwdev(dev);
1261 struct subchannel *sch;
1264 spin_lock_irq(cdev->ccwlock);
1265 switch (cdev->private->state) {
1266 case DEV_STATE_ONLINE:
1267 sch = to_subchannel(cdev->dev.parent);
1268 if ((sch->schib.pmcw.pam & sch->opm) == sch->vpm)
1271 case DEV_STATE_DISCONNECTED:
1272 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1273 cdev->private->dev_id.ssid,
1274 cdev->private->dev_id.devno);
1275 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1278 case DEV_STATE_DISCONNECTED_SENSE_ID:
1282 spin_unlock_irq(cdev->ccwlock);
1287 static void recovery_work_func(struct work_struct *unused)
1291 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1293 spin_lock_irq(&recovery_lock);
1294 if (!timer_pending(&recovery_timer)) {
1295 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1297 mod_timer(&recovery_timer, jiffies +
1298 recovery_delay[recovery_phase] * HZ);
1300 spin_unlock_irq(&recovery_lock);
1302 CIO_MSG_EVENT(3, "recovery: end\n");
1305 static DECLARE_WORK(recovery_work, recovery_work_func);
1307 static void recovery_func(struct timer_list *unused)
1310 * We can't do our recovery in softirq context and it's not
1311 * performance critical, so we schedule it.
1313 schedule_work(&recovery_work);
1316 void ccw_device_schedule_recovery(void)
1318 unsigned long flags;
1320 CIO_MSG_EVENT(3, "recovery: schedule\n");
1321 spin_lock_irqsave(&recovery_lock, flags);
1322 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1324 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1326 spin_unlock_irqrestore(&recovery_lock, flags);
1329 static int purge_fn(struct device *dev, void *data)
1331 struct ccw_device *cdev = to_ccwdev(dev);
1332 struct ccw_dev_id *id = &cdev->private->dev_id;
1334 spin_lock_irq(cdev->ccwlock);
1335 if (is_blacklisted(id->ssid, id->devno) &&
1336 (cdev->private->state == DEV_STATE_OFFLINE) &&
1337 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1338 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1340 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1341 atomic_set(&cdev->private->onoff, 0);
1343 spin_unlock_irq(cdev->ccwlock);
1344 /* Abort loop in case of pending signal. */
1345 if (signal_pending(current))
1352 * ccw_purge_blacklisted - purge unused, blacklisted devices
1354 * Unregister all ccw devices that are offline and on the blacklist.
1356 int ccw_purge_blacklisted(void)
1358 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1359 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1363 void ccw_device_set_disconnected(struct ccw_device *cdev)
1367 ccw_device_set_timeout(cdev, 0);
1368 cdev->private->flags.fake_irb = 0;
1369 cdev->private->state = DEV_STATE_DISCONNECTED;
1371 ccw_device_schedule_recovery();
1374 void ccw_device_set_notoper(struct ccw_device *cdev)
1376 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1378 CIO_TRACE_EVENT(2, "notoper");
1379 CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1380 ccw_device_set_timeout(cdev, 0);
1381 cio_disable_subchannel(sch);
1382 cdev->private->state = DEV_STATE_NOT_OPER;
1385 enum io_sch_action {
1390 IO_SCH_UNREG_ATTACH,
1398 static enum io_sch_action sch_get_action(struct subchannel *sch)
1400 struct ccw_device *cdev;
1402 cdev = sch_get_cdev(sch);
1403 if (cio_update_schib(sch)) {
1404 /* Not operational. */
1406 return IO_SCH_UNREG;
1407 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1408 return IO_SCH_UNREG;
1409 return IO_SCH_ORPH_UNREG;
1413 return IO_SCH_ATTACH;
1414 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1415 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1416 return IO_SCH_UNREG_ATTACH;
1417 return IO_SCH_ORPH_ATTACH;
1419 if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1420 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1421 return IO_SCH_UNREG_CDEV;
1424 if (device_is_disconnected(cdev))
1425 return IO_SCH_REPROBE;
1426 if (cdev->online && !cdev->private->flags.resuming)
1427 return IO_SCH_VERIFY;
1428 if (cdev->private->state == DEV_STATE_NOT_OPER)
1429 return IO_SCH_UNREG_ATTACH;
1434 * io_subchannel_sch_event - process subchannel event
1436 * @process: non-zero if function is called in process context
1438 * An unspecified event occurred for this subchannel. Adjust data according
1439 * to the current operational state of the subchannel and device. Return
1440 * zero when the event has been handled sufficiently or -EAGAIN when this
1441 * function should be called again in process context.
1443 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1445 unsigned long flags;
1446 struct ccw_device *cdev;
1447 struct ccw_dev_id dev_id;
1448 enum io_sch_action action;
1451 spin_lock_irqsave(sch->lock, flags);
1452 if (!device_is_registered(&sch->dev))
1454 if (work_pending(&sch->todo_work))
1456 cdev = sch_get_cdev(sch);
1457 if (cdev && work_pending(&cdev->private->todo_work))
1459 action = sch_get_action(sch);
1460 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1461 sch->schid.ssid, sch->schid.sch_no, process,
1463 /* Perform immediate actions while holding the lock. */
1465 case IO_SCH_REPROBE:
1466 /* Trigger device recognition. */
1467 ccw_device_trigger_reprobe(cdev);
1471 /* Trigger path verification. */
1472 io_subchannel_verify(sch);
1476 ccw_device_set_disconnected(cdev);
1479 case IO_SCH_ORPH_UNREG:
1480 case IO_SCH_ORPH_ATTACH:
1481 ccw_device_set_disconnected(cdev);
1483 case IO_SCH_UNREG_CDEV:
1484 case IO_SCH_UNREG_ATTACH:
1488 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1490 * Note: delayed work triggered by this event
1491 * and repeated calls to sch_event are synchronized
1492 * by the above check for work_pending(cdev).
1494 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1496 ccw_device_set_notoper(cdev);
1504 spin_unlock_irqrestore(sch->lock, flags);
1505 /* All other actions require process context. */
1508 /* Handle attached ccw device. */
1510 case IO_SCH_ORPH_UNREG:
1511 case IO_SCH_ORPH_ATTACH:
1512 /* Move ccw device to orphanage. */
1513 rc = ccw_device_move_to_orph(cdev);
1517 case IO_SCH_UNREG_CDEV:
1518 case IO_SCH_UNREG_ATTACH:
1519 spin_lock_irqsave(sch->lock, flags);
1520 if (cdev->private->flags.resuming) {
1521 /* Device will be handled later. */
1525 sch_set_cdev(sch, NULL);
1526 spin_unlock_irqrestore(sch->lock, flags);
1527 /* Unregister ccw device. */
1528 ccw_device_unregister(cdev);
1533 /* Handle subchannel. */
1535 case IO_SCH_ORPH_UNREG:
1537 if (!cdev || !cdev->private->flags.resuming)
1538 css_sch_device_unregister(sch);
1540 case IO_SCH_ORPH_ATTACH:
1541 case IO_SCH_UNREG_ATTACH:
1543 dev_id.ssid = sch->schid.ssid;
1544 dev_id.devno = sch->schib.pmcw.dev;
1545 cdev = get_ccwdev_by_dev_id(&dev_id);
1547 sch_create_and_recog_new_device(sch);
1550 rc = ccw_device_move_to_sch(cdev, sch);
1552 /* Release reference from get_ccwdev_by_dev_id() */
1553 put_device(&cdev->dev);
1556 spin_lock_irqsave(sch->lock, flags);
1557 ccw_device_trigger_reprobe(cdev);
1558 spin_unlock_irqrestore(sch->lock, flags);
1559 /* Release reference from get_ccwdev_by_dev_id() */
1560 put_device(&cdev->dev);
1568 spin_unlock_irqrestore(sch->lock, flags);
1573 static void ccw_device_set_int_class(struct ccw_device *cdev)
1575 struct ccw_driver *cdrv = cdev->drv;
1577 /* Note: we interpret class 0 in this context as an uninitialized
1578 * field since it translates to a non-I/O interrupt class. */
1579 if (cdrv->int_class != 0)
1580 cdev->private->int_class = cdrv->int_class;
1582 cdev->private->int_class = IRQIO_CIO;
1585 #ifdef CONFIG_CCW_CONSOLE
1586 int __init ccw_device_enable_console(struct ccw_device *cdev)
1588 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1591 if (!cdev->drv || !cdev->handler)
1594 io_subchannel_init_fields(sch);
1595 rc = cio_commit_config(sch);
1598 sch->driver = &io_subchannel_driver;
1599 io_subchannel_recog(cdev, sch);
1600 /* Now wait for the async. recognition to come to an end. */
1601 spin_lock_irq(cdev->ccwlock);
1602 while (!dev_fsm_final_state(cdev))
1603 ccw_device_wait_idle(cdev);
1605 /* Hold on to an extra reference while device is online. */
1606 get_device(&cdev->dev);
1607 rc = ccw_device_online(cdev);
1611 while (!dev_fsm_final_state(cdev))
1612 ccw_device_wait_idle(cdev);
1614 if (cdev->private->state == DEV_STATE_ONLINE)
1619 spin_unlock_irq(cdev->ccwlock);
1620 if (rc) /* Give up online reference since onlining failed. */
1621 put_device(&cdev->dev);
1625 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv)
1627 struct io_subchannel_private *io_priv;
1628 struct ccw_device *cdev;
1629 struct subchannel *sch;
1631 sch = cio_probe_console();
1633 return ERR_CAST(sch);
1635 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1638 io_priv->dma_area = dma_alloc_coherent(&sch->dev,
1639 sizeof(*io_priv->dma_area),
1640 &io_priv->dma_area_dma, GFP_KERNEL);
1641 if (!io_priv->dma_area)
1643 set_io_private(sch, io_priv);
1644 cdev = io_subchannel_create_ccwdev(sch);
1646 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area),
1647 io_priv->dma_area, io_priv->dma_area_dma);
1648 set_io_private(sch, NULL);
1649 put_device(&sch->dev);
1654 ccw_device_set_int_class(cdev);
1660 put_device(&sch->dev);
1661 return ERR_PTR(-ENOMEM);
1664 void __init ccw_device_destroy_console(struct ccw_device *cdev)
1666 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1667 struct io_subchannel_private *io_priv = to_io_private(sch);
1669 set_io_private(sch, NULL);
1670 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area),
1671 io_priv->dma_area, io_priv->dma_area_dma);
1672 put_device(&sch->dev);
1673 put_device(&cdev->dev);
1678 * ccw_device_wait_idle() - busy wait for device to become idle
1681 * Poll until activity control is zero, that is, no function or data
1682 * transfer is pending/active.
1683 * Called with device lock being held.
1685 void ccw_device_wait_idle(struct ccw_device *cdev)
1687 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1691 if (sch->schib.scsw.cmd.actl == 0)
1697 static int ccw_device_pm_restore(struct device *dev);
1699 int ccw_device_force_console(struct ccw_device *cdev)
1701 return ccw_device_pm_restore(&cdev->dev);
1703 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1707 * get_ccwdev_by_busid() - obtain device from a bus id
1708 * @cdrv: driver the device is owned by
1709 * @bus_id: bus id of the device to be searched
1711 * This function searches all devices owned by @cdrv for a device with a bus
1712 * id matching @bus_id.
1714 * If a match is found, its reference count of the found device is increased
1715 * and it is returned; else %NULL is returned.
1717 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1722 dev = driver_find_device_by_name(&cdrv->driver, bus_id);
1724 return dev ? to_ccwdev(dev) : NULL;
1727 /************************** device driver handling ************************/
1729 /* This is the implementation of the ccw_driver class. The probe, remove
1730 * and release methods are initially very similar to the device_driver
1731 * implementations, with the difference that they have ccw_device
1734 * A ccw driver also contains the information that is needed for
1738 ccw_device_probe (struct device *dev)
1740 struct ccw_device *cdev = to_ccwdev(dev);
1741 struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1744 cdev->drv = cdrv; /* to let the driver call _set_online */
1745 ccw_device_set_int_class(cdev);
1746 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1749 cdev->private->int_class = IRQIO_CIO;
1756 static int ccw_device_remove(struct device *dev)
1758 struct ccw_device *cdev = to_ccwdev(dev);
1759 struct ccw_driver *cdrv = cdev->drv;
1760 struct subchannel *sch;
1766 spin_lock_irq(cdev->ccwlock);
1769 ret = ccw_device_offline(cdev);
1770 spin_unlock_irq(cdev->ccwlock);
1772 wait_event(cdev->private->wait_q,
1773 dev_fsm_final_state(cdev));
1775 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1776 "device 0.%x.%04x\n",
1777 ret, cdev->private->dev_id.ssid,
1778 cdev->private->dev_id.devno);
1779 /* Give up reference obtained in ccw_device_set_online(). */
1780 put_device(&cdev->dev);
1781 spin_lock_irq(cdev->ccwlock);
1783 ccw_device_set_timeout(cdev, 0);
1785 cdev->private->int_class = IRQIO_CIO;
1786 sch = to_subchannel(cdev->dev.parent);
1787 spin_unlock_irq(cdev->ccwlock);
1788 io_subchannel_quiesce(sch);
1789 __disable_cmf(cdev);
1794 static void ccw_device_shutdown(struct device *dev)
1796 struct ccw_device *cdev;
1798 cdev = to_ccwdev(dev);
1799 if (cdev->drv && cdev->drv->shutdown)
1800 cdev->drv->shutdown(cdev);
1801 __disable_cmf(cdev);
1804 static int ccw_device_pm_prepare(struct device *dev)
1806 struct ccw_device *cdev = to_ccwdev(dev);
1808 if (work_pending(&cdev->private->todo_work))
1810 /* Fail while device is being set online/offline. */
1811 if (atomic_read(&cdev->private->onoff))
1814 if (cdev->online && cdev->drv && cdev->drv->prepare)
1815 return cdev->drv->prepare(cdev);
1820 static void ccw_device_pm_complete(struct device *dev)
1822 struct ccw_device *cdev = to_ccwdev(dev);
1824 if (cdev->online && cdev->drv && cdev->drv->complete)
1825 cdev->drv->complete(cdev);
1828 static int ccw_device_pm_freeze(struct device *dev)
1830 struct ccw_device *cdev = to_ccwdev(dev);
1831 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1832 int ret, cm_enabled;
1834 /* Fail suspend while device is in transistional state. */
1835 if (!dev_fsm_final_state(cdev))
1839 if (cdev->drv && cdev->drv->freeze) {
1840 ret = cdev->drv->freeze(cdev);
1845 spin_lock_irq(sch->lock);
1846 cm_enabled = cdev->private->cmb != NULL;
1847 spin_unlock_irq(sch->lock);
1849 /* Don't have the css write on memory. */
1850 ret = ccw_set_cmf(cdev, 0);
1854 /* From here on, disallow device driver I/O. */
1855 spin_lock_irq(sch->lock);
1856 ret = cio_disable_subchannel(sch);
1857 spin_unlock_irq(sch->lock);
1862 static int ccw_device_pm_thaw(struct device *dev)
1864 struct ccw_device *cdev = to_ccwdev(dev);
1865 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1866 int ret, cm_enabled;
1871 spin_lock_irq(sch->lock);
1872 /* Allow device driver I/O again. */
1873 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1874 cm_enabled = cdev->private->cmb != NULL;
1875 spin_unlock_irq(sch->lock);
1880 ret = ccw_set_cmf(cdev, 1);
1885 if (cdev->drv && cdev->drv->thaw)
1886 ret = cdev->drv->thaw(cdev);
1891 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1893 struct subchannel *sch = to_subchannel(cdev->dev.parent);
1895 spin_lock_irq(sch->lock);
1896 if (cio_is_console(sch->schid)) {
1897 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1901 * While we were sleeping, devices may have gone or become
1902 * available again. Kick re-detection.
1904 cdev->private->flags.resuming = 1;
1905 cdev->private->path_new_mask = LPM_ANYPATH;
1906 css_sched_sch_todo(sch, SCH_TODO_EVAL);
1907 spin_unlock_irq(sch->lock);
1908 css_wait_for_slow_path();
1910 /* cdev may have been moved to a different subchannel. */
1911 sch = to_subchannel(cdev->dev.parent);
1912 spin_lock_irq(sch->lock);
1913 if (cdev->private->state != DEV_STATE_ONLINE &&
1914 cdev->private->state != DEV_STATE_OFFLINE)
1917 ccw_device_recognition(cdev);
1918 spin_unlock_irq(sch->lock);
1919 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1920 cdev->private->state == DEV_STATE_DISCONNECTED);
1921 spin_lock_irq(sch->lock);
1924 cdev->private->flags.resuming = 0;
1925 spin_unlock_irq(sch->lock);
1928 static int resume_handle_boxed(struct ccw_device *cdev)
1930 cdev->private->state = DEV_STATE_BOXED;
1931 if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1933 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1937 static int resume_handle_disc(struct ccw_device *cdev)
1939 cdev->private->state = DEV_STATE_DISCONNECTED;
1940 if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1942 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1946 static int ccw_device_pm_restore(struct device *dev)
1948 struct ccw_device *cdev = to_ccwdev(dev);
1949 struct subchannel *sch;
1952 __ccw_device_pm_restore(cdev);
1953 sch = to_subchannel(cdev->dev.parent);
1954 spin_lock_irq(sch->lock);
1955 if (cio_is_console(sch->schid))
1958 /* check recognition results */
1959 switch (cdev->private->state) {
1960 case DEV_STATE_OFFLINE:
1961 case DEV_STATE_ONLINE:
1962 cdev->private->flags.donotify = 0;
1964 case DEV_STATE_BOXED:
1965 ret = resume_handle_boxed(cdev);
1970 ret = resume_handle_disc(cdev);
1975 /* check if the device type has changed */
1976 if (!ccw_device_test_sense_data(cdev)) {
1977 ccw_device_update_sense_data(cdev);
1978 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1985 if (ccw_device_online(cdev)) {
1986 ret = resume_handle_disc(cdev);
1991 spin_unlock_irq(sch->lock);
1992 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1993 spin_lock_irq(sch->lock);
1995 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1996 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
2001 /* reenable cmf, if needed */
2002 if (cdev->private->cmb) {
2003 spin_unlock_irq(sch->lock);
2004 ret = ccw_set_cmf(cdev, 1);
2005 spin_lock_irq(sch->lock);
2007 CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
2008 "(rc=%d)\n", cdev->private->dev_id.ssid,
2009 cdev->private->dev_id.devno, ret);
2015 spin_unlock_irq(sch->lock);
2016 if (cdev->online && cdev->drv && cdev->drv->restore)
2017 ret = cdev->drv->restore(cdev);
2021 spin_unlock_irq(sch->lock);
2025 static const struct dev_pm_ops ccw_pm_ops = {
2026 .prepare = ccw_device_pm_prepare,
2027 .complete = ccw_device_pm_complete,
2028 .freeze = ccw_device_pm_freeze,
2029 .thaw = ccw_device_pm_thaw,
2030 .restore = ccw_device_pm_restore,
2033 static struct bus_type ccw_bus_type = {
2035 .match = ccw_bus_match,
2036 .uevent = ccw_uevent,
2037 .probe = ccw_device_probe,
2038 .remove = ccw_device_remove,
2039 .shutdown = ccw_device_shutdown,
2044 * ccw_driver_register() - register a ccw driver
2045 * @cdriver: driver to be registered
2047 * This function is mainly a wrapper around driver_register().
2049 * %0 on success and a negative error value on failure.
2051 int ccw_driver_register(struct ccw_driver *cdriver)
2053 struct device_driver *drv = &cdriver->driver;
2055 drv->bus = &ccw_bus_type;
2057 return driver_register(drv);
2061 * ccw_driver_unregister() - deregister a ccw driver
2062 * @cdriver: driver to be deregistered
2064 * This function is mainly a wrapper around driver_unregister().
2066 void ccw_driver_unregister(struct ccw_driver *cdriver)
2068 driver_unregister(&cdriver->driver);
2071 static void ccw_device_todo(struct work_struct *work)
2073 struct ccw_device_private *priv;
2074 struct ccw_device *cdev;
2075 struct subchannel *sch;
2076 enum cdev_todo todo;
2078 priv = container_of(work, struct ccw_device_private, todo_work);
2080 sch = to_subchannel(cdev->dev.parent);
2081 /* Find out todo. */
2082 spin_lock_irq(cdev->ccwlock);
2084 priv->todo = CDEV_TODO_NOTHING;
2085 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2086 priv->dev_id.ssid, priv->dev_id.devno, todo);
2087 spin_unlock_irq(cdev->ccwlock);
2090 case CDEV_TODO_ENABLE_CMF:
2093 case CDEV_TODO_REBIND:
2094 ccw_device_do_unbind_bind(cdev);
2096 case CDEV_TODO_REGISTER:
2097 io_subchannel_register(cdev);
2099 case CDEV_TODO_UNREG_EVAL:
2100 if (!sch_is_pseudo_sch(sch))
2101 css_schedule_eval(sch->schid);
2103 case CDEV_TODO_UNREG:
2104 if (sch_is_pseudo_sch(sch))
2105 ccw_device_unregister(cdev);
2107 ccw_device_call_sch_unregister(cdev);
2112 /* Release workqueue ref. */
2113 put_device(&cdev->dev);
2117 * ccw_device_sched_todo - schedule ccw device operation
2121 * Schedule the operation identified by @todo to be performed on the slow path
2122 * workqueue. Do nothing if another operation with higher priority is already
2123 * scheduled. Needs to be called with ccwdev lock held.
2125 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2127 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2128 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2130 if (cdev->private->todo >= todo)
2132 cdev->private->todo = todo;
2133 /* Get workqueue ref. */
2134 if (!get_device(&cdev->dev))
2136 if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2137 /* Already queued, release workqueue ref. */
2138 put_device(&cdev->dev);
2143 * ccw_device_siosl() - initiate logging
2146 * This function is used to invoke model-dependent logging within the channel
2149 int ccw_device_siosl(struct ccw_device *cdev)
2151 struct subchannel *sch = to_subchannel(cdev->dev.parent);
2153 return chsc_siosl(sch->schid);
2155 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2157 EXPORT_SYMBOL(ccw_device_set_online);
2158 EXPORT_SYMBOL(ccw_device_set_offline);
2159 EXPORT_SYMBOL(ccw_driver_register);
2160 EXPORT_SYMBOL(ccw_driver_unregister);
2161 EXPORT_SYMBOL(get_ccwdev_by_busid);