2 * driver for channel subsystem
4 * Copyright IBM Corp. 2002, 2009
6 * Author(s): Arnd Bergmann (arndb@de.ibm.com)
7 * Cornelia Huck (cornelia.huck@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/device.h>
16 #include <linux/slab.h>
17 #include <linux/errno.h>
18 #include <linux/list.h>
19 #include <linux/reboot.h>
20 #include <linux/suspend.h>
26 #include "cio_debug.h"
33 int css_init_done = 0;
36 struct channel_subsystem *channel_subsystems[__MAX_CSSID + 1];
39 for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *data)
41 struct subchannel_id schid;
44 init_subchannel_id(&schid);
48 ret = fn(schid, data);
51 } while (schid.sch_no++ < __MAX_SUBCHANNEL);
53 } while (schid.ssid++ < max_ssid);
60 int (*fn_known_sch)(struct subchannel *, void *);
61 int (*fn_unknown_sch)(struct subchannel_id, void *);
64 static int call_fn_known_sch(struct device *dev, void *data)
66 struct subchannel *sch = to_subchannel(dev);
67 struct cb_data *cb = data;
70 idset_sch_del(cb->set, sch->schid);
72 rc = cb->fn_known_sch(sch, cb->data);
76 static int call_fn_unknown_sch(struct subchannel_id schid, void *data)
78 struct cb_data *cb = data;
81 if (idset_sch_contains(cb->set, schid))
82 rc = cb->fn_unknown_sch(schid, cb->data);
86 static int call_fn_all_sch(struct subchannel_id schid, void *data)
88 struct cb_data *cb = data;
89 struct subchannel *sch;
92 sch = get_subchannel_by_schid(schid);
95 rc = cb->fn_known_sch(sch, cb->data);
96 put_device(&sch->dev);
98 if (cb->fn_unknown_sch)
99 rc = cb->fn_unknown_sch(schid, cb->data);
105 int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
106 int (*fn_unknown)(struct subchannel_id,
113 cb.fn_known_sch = fn_known;
114 cb.fn_unknown_sch = fn_unknown;
116 cb.set = idset_sch_new();
118 /* fall back to brute force scanning in case of oom */
119 return for_each_subchannel(call_fn_all_sch, &cb);
123 /* Process registered subchannels. */
124 rc = bus_for_each_dev(&css_bus_type, NULL, &cb, call_fn_known_sch);
127 /* Process unregistered subchannels. */
129 rc = for_each_subchannel(call_fn_unknown_sch, &cb);
136 static void css_sch_todo(struct work_struct *work);
138 static struct subchannel *
139 css_alloc_subchannel(struct subchannel_id schid)
141 struct subchannel *sch;
144 sch = kmalloc (sizeof (*sch), GFP_KERNEL | GFP_DMA);
146 return ERR_PTR(-ENOMEM);
147 ret = cio_validate_subchannel (sch, schid);
152 INIT_WORK(&sch->todo_work, css_sch_todo);
157 css_subchannel_release(struct device *dev)
159 struct subchannel *sch;
161 sch = to_subchannel(dev);
162 if (!cio_is_console(sch->schid)) {
163 /* Reset intparm to zeroes. */
164 sch->config.intparm = 0;
165 cio_commit_config(sch);
171 static int css_sch_device_register(struct subchannel *sch)
175 mutex_lock(&sch->reg_mutex);
176 dev_set_name(&sch->dev, "0.%x.%04x", sch->schid.ssid,
178 ret = device_register(&sch->dev);
179 mutex_unlock(&sch->reg_mutex);
184 * css_sch_device_unregister - unregister a subchannel
185 * @sch: subchannel to be unregistered
187 void css_sch_device_unregister(struct subchannel *sch)
189 mutex_lock(&sch->reg_mutex);
190 if (device_is_registered(&sch->dev))
191 device_unregister(&sch->dev);
192 mutex_unlock(&sch->reg_mutex);
194 EXPORT_SYMBOL_GPL(css_sch_device_unregister);
196 static void css_sch_todo(struct work_struct *work)
198 struct subchannel *sch;
201 sch = container_of(work, struct subchannel, todo_work);
203 spin_lock_irq(sch->lock);
205 CIO_MSG_EVENT(4, "sch_todo: sch=0.%x.%04x, todo=%d\n", sch->schid.ssid,
206 sch->schid.sch_no, todo);
207 sch->todo = SCH_TODO_NOTHING;
208 spin_unlock_irq(sch->lock);
210 if (todo == SCH_TODO_UNREG)
211 css_sch_device_unregister(sch);
212 /* Release workqueue ref. */
213 put_device(&sch->dev);
217 * css_sched_sch_todo - schedule a subchannel operation
221 * Schedule the operation identified by @todo to be performed on the slow path
222 * workqueue. Do nothing if another operation with higher priority is already
223 * scheduled. Needs to be called with subchannel lock held.
225 void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo)
227 CIO_MSG_EVENT(4, "sch_todo: sched sch=0.%x.%04x todo=%d\n",
228 sch->schid.ssid, sch->schid.sch_no, todo);
229 if (sch->todo >= todo)
231 /* Get workqueue ref. */
232 if (!get_device(&sch->dev))
235 if (!queue_work(slow_path_wq, &sch->todo_work)) {
236 /* Already queued, release workqueue ref. */
237 put_device(&sch->dev);
241 static void ssd_from_pmcw(struct chsc_ssd_info *ssd, struct pmcw *pmcw)
246 memset(ssd, 0, sizeof(struct chsc_ssd_info));
247 ssd->path_mask = pmcw->pim;
248 for (i = 0; i < 8; i++) {
250 if (pmcw->pim & mask) {
251 chp_id_init(&ssd->chpid[i]);
252 ssd->chpid[i].id = pmcw->chpid[i];
257 static void ssd_register_chpids(struct chsc_ssd_info *ssd)
262 for (i = 0; i < 8; i++) {
264 if (ssd->path_mask & mask)
265 if (!chp_is_registered(ssd->chpid[i]))
266 chp_new(ssd->chpid[i]);
270 void css_update_ssd_info(struct subchannel *sch)
274 if (cio_is_console(sch->schid)) {
275 /* Console is initialized too early for functions requiring
276 * memory allocation. */
277 ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
279 ret = chsc_get_ssd_info(sch->schid, &sch->ssd_info);
281 ssd_from_pmcw(&sch->ssd_info, &sch->schib.pmcw);
282 ssd_register_chpids(&sch->ssd_info);
286 static ssize_t type_show(struct device *dev, struct device_attribute *attr,
289 struct subchannel *sch = to_subchannel(dev);
291 return sprintf(buf, "%01x\n", sch->st);
294 static DEVICE_ATTR(type, 0444, type_show, NULL);
296 static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
299 struct subchannel *sch = to_subchannel(dev);
301 return sprintf(buf, "css:t%01X\n", sch->st);
304 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
306 static struct attribute *subch_attrs[] = {
308 &dev_attr_modalias.attr,
312 static struct attribute_group subch_attr_group = {
313 .attrs = subch_attrs,
316 static const struct attribute_group *default_subch_attr_groups[] = {
321 static int css_register_subchannel(struct subchannel *sch)
325 /* Initialize the subchannel structure */
326 sch->dev.parent = &channel_subsystems[0]->device;
327 sch->dev.bus = &css_bus_type;
328 sch->dev.release = &css_subchannel_release;
329 sch->dev.groups = default_subch_attr_groups;
331 * We don't want to generate uevents for I/O subchannels that don't
332 * have a working ccw device behind them since they will be
333 * unregistered before they can be used anyway, so we delay the add
334 * uevent until after device recognition was successful.
335 * Note that we suppress the uevent for all subchannel types;
336 * the subchannel driver can decide itself when it wants to inform
337 * userspace of its existence.
339 dev_set_uevent_suppress(&sch->dev, 1);
340 css_update_ssd_info(sch);
341 /* make it known to the system */
342 ret = css_sch_device_register(sch);
344 CIO_MSG_EVENT(0, "Could not register sch 0.%x.%04x: %d\n",
345 sch->schid.ssid, sch->schid.sch_no, ret);
350 * No driver matched. Generate the uevent now so that
351 * a fitting driver module may be loaded based on the
354 dev_set_uevent_suppress(&sch->dev, 0);
355 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
360 int css_probe_device(struct subchannel_id schid)
363 struct subchannel *sch;
365 if (cio_is_console(schid))
366 sch = cio_get_console_subchannel();
368 sch = css_alloc_subchannel(schid);
372 ret = css_register_subchannel(sch);
374 if (!cio_is_console(schid))
375 put_device(&sch->dev);
381 check_subchannel(struct device * dev, void * data)
383 struct subchannel *sch;
384 struct subchannel_id *schid = data;
386 sch = to_subchannel(dev);
387 return schid_equal(&sch->schid, schid);
391 get_subchannel_by_schid(struct subchannel_id schid)
395 dev = bus_find_device(&css_bus_type, NULL,
396 &schid, check_subchannel);
398 return dev ? to_subchannel(dev) : NULL;
402 * css_sch_is_valid() - check if a subchannel is valid
403 * @schib: subchannel information block for the subchannel
405 int css_sch_is_valid(struct schib *schib)
407 if ((schib->pmcw.st == SUBCHANNEL_TYPE_IO) && !schib->pmcw.dnv)
409 if ((schib->pmcw.st == SUBCHANNEL_TYPE_MSG) && !schib->pmcw.w)
413 EXPORT_SYMBOL_GPL(css_sch_is_valid);
415 static int css_evaluate_new_subchannel(struct subchannel_id schid, int slow)
420 /* Will be done on the slow path. */
423 if (stsch_err(schid, &schib) || !css_sch_is_valid(&schib)) {
424 /* Unusable - ignore. */
427 CIO_MSG_EVENT(4, "event: sch 0.%x.%04x, new\n", schid.ssid,
430 return css_probe_device(schid);
433 static int css_evaluate_known_subchannel(struct subchannel *sch, int slow)
438 if (sch->driver->sch_event)
439 ret = sch->driver->sch_event(sch, slow);
442 "Got subchannel machine check but "
443 "no sch_event handler provided.\n");
445 if (ret != 0 && ret != -EAGAIN) {
446 CIO_MSG_EVENT(2, "eval: sch 0.%x.%04x, rc=%d\n",
447 sch->schid.ssid, sch->schid.sch_no, ret);
452 static void css_evaluate_subchannel(struct subchannel_id schid, int slow)
454 struct subchannel *sch;
457 sch = get_subchannel_by_schid(schid);
459 ret = css_evaluate_known_subchannel(sch, slow);
460 put_device(&sch->dev);
462 ret = css_evaluate_new_subchannel(schid, slow);
464 css_schedule_eval(schid);
467 static struct idset *slow_subchannel_set;
468 static spinlock_t slow_subchannel_lock;
469 static wait_queue_head_t css_eval_wq;
470 static atomic_t css_eval_scheduled;
472 static int __init slow_subchannel_init(void)
474 spin_lock_init(&slow_subchannel_lock);
475 atomic_set(&css_eval_scheduled, 0);
476 init_waitqueue_head(&css_eval_wq);
477 slow_subchannel_set = idset_sch_new();
478 if (!slow_subchannel_set) {
479 CIO_MSG_EVENT(0, "could not allocate slow subchannel set\n");
485 static int slow_eval_known_fn(struct subchannel *sch, void *data)
490 spin_lock_irq(&slow_subchannel_lock);
491 eval = idset_sch_contains(slow_subchannel_set, sch->schid);
492 idset_sch_del(slow_subchannel_set, sch->schid);
493 spin_unlock_irq(&slow_subchannel_lock);
495 rc = css_evaluate_known_subchannel(sch, 1);
497 css_schedule_eval(sch->schid);
502 static int slow_eval_unknown_fn(struct subchannel_id schid, void *data)
507 spin_lock_irq(&slow_subchannel_lock);
508 eval = idset_sch_contains(slow_subchannel_set, schid);
509 idset_sch_del(slow_subchannel_set, schid);
510 spin_unlock_irq(&slow_subchannel_lock);
512 rc = css_evaluate_new_subchannel(schid, 1);
515 css_schedule_eval(schid);
521 /* These should abort looping */
530 static void css_slow_path_func(struct work_struct *unused)
534 CIO_TRACE_EVENT(4, "slowpath");
535 for_each_subchannel_staged(slow_eval_known_fn, slow_eval_unknown_fn,
537 spin_lock_irqsave(&slow_subchannel_lock, flags);
538 if (idset_is_empty(slow_subchannel_set)) {
539 atomic_set(&css_eval_scheduled, 0);
540 wake_up(&css_eval_wq);
542 spin_unlock_irqrestore(&slow_subchannel_lock, flags);
545 static DECLARE_WORK(slow_path_work, css_slow_path_func);
546 struct workqueue_struct *slow_path_wq;
548 void css_schedule_eval(struct subchannel_id schid)
552 spin_lock_irqsave(&slow_subchannel_lock, flags);
553 idset_sch_add(slow_subchannel_set, schid);
554 atomic_set(&css_eval_scheduled, 1);
555 queue_work(slow_path_wq, &slow_path_work);
556 spin_unlock_irqrestore(&slow_subchannel_lock, flags);
559 void css_schedule_eval_all(void)
563 spin_lock_irqsave(&slow_subchannel_lock, flags);
564 idset_fill(slow_subchannel_set);
565 atomic_set(&css_eval_scheduled, 1);
566 queue_work(slow_path_wq, &slow_path_work);
567 spin_unlock_irqrestore(&slow_subchannel_lock, flags);
570 static int __unset_registered(struct device *dev, void *data)
572 struct idset *set = data;
573 struct subchannel *sch = to_subchannel(dev);
575 idset_sch_del(set, sch->schid);
579 void css_schedule_eval_all_unreg(void)
582 struct idset *unreg_set;
584 /* Find unregistered subchannels. */
585 unreg_set = idset_sch_new();
588 css_schedule_eval_all();
591 idset_fill(unreg_set);
592 bus_for_each_dev(&css_bus_type, NULL, unreg_set, __unset_registered);
593 /* Apply to slow_subchannel_set. */
594 spin_lock_irqsave(&slow_subchannel_lock, flags);
595 idset_add_set(slow_subchannel_set, unreg_set);
596 atomic_set(&css_eval_scheduled, 1);
597 queue_work(slow_path_wq, &slow_path_work);
598 spin_unlock_irqrestore(&slow_subchannel_lock, flags);
599 idset_free(unreg_set);
602 void css_wait_for_slow_path(void)
604 flush_workqueue(slow_path_wq);
607 /* Schedule reprobing of all unregistered subchannels. */
608 void css_schedule_reprobe(void)
610 css_schedule_eval_all_unreg();
612 EXPORT_SYMBOL_GPL(css_schedule_reprobe);
615 * Called from the machine check handler for subchannel report words.
617 static void css_process_crw(struct crw *crw0, struct crw *crw1, int overflow)
619 struct subchannel_id mchk_schid;
622 css_schedule_eval_all();
625 CIO_CRW_EVENT(2, "CRW0 reports slct=%d, oflw=%d, "
626 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
627 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
628 crw0->erc, crw0->rsid);
630 CIO_CRW_EVENT(2, "CRW1 reports slct=%d, oflw=%d, "
631 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
632 crw1->slct, crw1->oflw, crw1->chn, crw1->rsc,
633 crw1->anc, crw1->erc, crw1->rsid);
634 init_subchannel_id(&mchk_schid);
635 mchk_schid.sch_no = crw0->rsid;
637 mchk_schid.ssid = (crw1->rsid >> 8) & 3;
640 * Since we are always presented with IPI in the CRW, we have to
641 * use stsch() to find out if the subchannel in question has come
644 css_evaluate_subchannel(mchk_schid, 0);
648 css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
650 if (css_general_characteristics.mcss) {
651 css->global_pgid.pgid_high.ext_cssid.version = 0x80;
652 css->global_pgid.pgid_high.ext_cssid.cssid = css->cssid;
655 css->global_pgid.pgid_high.cpu_addr = stap();
657 css->global_pgid.pgid_high.cpu_addr = 0;
660 css->global_pgid.cpu_id = S390_lowcore.cpu_id.ident;
661 css->global_pgid.cpu_model = S390_lowcore.cpu_id.machine;
662 css->global_pgid.tod_high = tod_high;
667 channel_subsystem_release(struct device *dev)
669 struct channel_subsystem *css;
672 mutex_destroy(&css->mutex);
673 if (css->pseudo_subchannel) {
674 /* Implies that it has been generated but never registered. */
675 css_subchannel_release(&css->pseudo_subchannel->dev);
676 css->pseudo_subchannel = NULL;
682 css_cm_enable_show(struct device *dev, struct device_attribute *attr,
685 struct channel_subsystem *css = to_css(dev);
690 mutex_lock(&css->mutex);
691 ret = sprintf(buf, "%x\n", css->cm_enabled);
692 mutex_unlock(&css->mutex);
697 css_cm_enable_store(struct device *dev, struct device_attribute *attr,
698 const char *buf, size_t count)
700 struct channel_subsystem *css = to_css(dev);
704 ret = strict_strtoul(buf, 16, &val);
707 mutex_lock(&css->mutex);
710 ret = css->cm_enabled ? chsc_secm(css, 0) : 0;
713 ret = css->cm_enabled ? 0 : chsc_secm(css, 1);
718 mutex_unlock(&css->mutex);
719 return ret < 0 ? ret : count;
722 static DEVICE_ATTR(cm_enable, 0644, css_cm_enable_show, css_cm_enable_store);
724 static int __init setup_css(int nr)
728 struct channel_subsystem *css;
730 css = channel_subsystems[nr];
731 memset(css, 0, sizeof(struct channel_subsystem));
732 css->pseudo_subchannel =
733 kzalloc(sizeof(*css->pseudo_subchannel), GFP_KERNEL);
734 if (!css->pseudo_subchannel)
736 css->pseudo_subchannel->dev.parent = &css->device;
737 css->pseudo_subchannel->dev.release = css_subchannel_release;
738 dev_set_name(&css->pseudo_subchannel->dev, "defunct");
739 mutex_init(&css->pseudo_subchannel->reg_mutex);
740 ret = cio_create_sch_lock(css->pseudo_subchannel);
742 kfree(css->pseudo_subchannel);
745 mutex_init(&css->mutex);
748 dev_set_name(&css->device, "css%x", nr);
749 css->device.release = channel_subsystem_release;
750 tod_high = (u32) (get_clock() >> 32);
751 css_generate_pgid(css, tod_high);
755 static int css_reboot_event(struct notifier_block *this,
762 for (i = 0; i <= __MAX_CSSID; i++) {
763 struct channel_subsystem *css;
765 css = channel_subsystems[i];
766 mutex_lock(&css->mutex);
768 if (chsc_secm(css, 0))
770 mutex_unlock(&css->mutex);
776 static struct notifier_block css_reboot_notifier = {
777 .notifier_call = css_reboot_event,
781 * Since the css devices are neither on a bus nor have a class
782 * nor have a special device type, we cannot stop/restart channel
783 * path measurements via the normal suspend/resume callbacks, but have
786 static int css_power_event(struct notifier_block *this, unsigned long event,
793 case PM_HIBERNATION_PREPARE:
794 case PM_SUSPEND_PREPARE:
796 for (i = 0; i <= __MAX_CSSID; i++) {
797 struct channel_subsystem *css;
799 css = channel_subsystems[i];
800 mutex_lock(&css->mutex);
801 if (!css->cm_enabled) {
802 mutex_unlock(&css->mutex);
805 secm_area = (void *)get_zeroed_page(GFP_KERNEL |
808 if (__chsc_do_secm(css, 0, secm_area))
810 free_page((unsigned long)secm_area);
814 mutex_unlock(&css->mutex);
817 case PM_POST_HIBERNATION:
818 case PM_POST_SUSPEND:
820 for (i = 0; i <= __MAX_CSSID; i++) {
821 struct channel_subsystem *css;
823 css = channel_subsystems[i];
824 mutex_lock(&css->mutex);
825 if (!css->cm_enabled) {
826 mutex_unlock(&css->mutex);
829 secm_area = (void *)get_zeroed_page(GFP_KERNEL |
832 if (__chsc_do_secm(css, 1, secm_area))
834 free_page((unsigned long)secm_area);
838 mutex_unlock(&css->mutex);
840 /* search for subchannels, which appeared during hibernation */
841 css_schedule_reprobe();
849 static struct notifier_block css_power_notifier = {
850 .notifier_call = css_power_event,
854 * Now that the driver core is running, we can setup our channel subsystem.
855 * The struct subchannel's are created during probing (except for the
856 * static console subchannel).
858 static int __init css_bus_init(void)
862 ret = chsc_determine_css_characteristics();
866 ret = chsc_alloc_sei_area();
870 /* Try to enable MSS. */
871 ret = chsc_enable_facility(CHSC_SDA_OC_MSS);
873 case 0: /* Success. */
874 max_ssid = __MAX_SSID;
882 ret = slow_subchannel_init();
886 ret = crw_register_handler(CRW_RSC_SCH, css_process_crw);
890 if ((ret = bus_register(&css_bus_type)))
893 /* Setup css structure. */
894 for (i = 0; i <= __MAX_CSSID; i++) {
895 struct channel_subsystem *css;
897 css = kmalloc(sizeof(struct channel_subsystem), GFP_KERNEL);
902 channel_subsystems[i] = css;
905 kfree(channel_subsystems[i]);
908 ret = device_register(&css->device);
910 put_device(&css->device);
913 if (css_chsc_characteristics.secm) {
914 ret = device_create_file(&css->device,
915 &dev_attr_cm_enable);
919 ret = device_register(&css->pseudo_subchannel->dev);
921 put_device(&css->pseudo_subchannel->dev);
925 ret = register_reboot_notifier(&css_reboot_notifier);
928 ret = register_pm_notifier(&css_power_notifier);
930 unregister_reboot_notifier(&css_reboot_notifier);
935 /* Enable default isc for I/O subchannels. */
936 isc_register(IO_SCH_ISC);
940 if (css_chsc_characteristics.secm)
941 device_remove_file(&channel_subsystems[i]->device,
942 &dev_attr_cm_enable);
944 device_unregister(&channel_subsystems[i]->device);
947 struct channel_subsystem *css;
950 css = channel_subsystems[i];
951 device_unregister(&css->pseudo_subchannel->dev);
952 css->pseudo_subchannel = NULL;
953 if (css_chsc_characteristics.secm)
954 device_remove_file(&css->device,
955 &dev_attr_cm_enable);
956 device_unregister(&css->device);
958 bus_unregister(&css_bus_type);
960 crw_unregister_handler(CRW_RSC_CSS);
961 chsc_free_sei_area();
962 idset_free(slow_subchannel_set);
963 pr_alert("The CSS device driver initialization failed with "
968 static void __init css_bus_cleanup(void)
970 struct channel_subsystem *css;
973 for (i = 0; i <= __MAX_CSSID; i++) {
974 css = channel_subsystems[i];
975 device_unregister(&css->pseudo_subchannel->dev);
976 css->pseudo_subchannel = NULL;
977 if (css_chsc_characteristics.secm)
978 device_remove_file(&css->device, &dev_attr_cm_enable);
979 device_unregister(&css->device);
981 bus_unregister(&css_bus_type);
982 crw_unregister_handler(CRW_RSC_CSS);
983 chsc_free_sei_area();
984 idset_free(slow_subchannel_set);
985 isc_unregister(IO_SCH_ISC);
988 static int __init channel_subsystem_init(void)
992 ret = css_bus_init();
996 ret = io_subchannel_init();
1002 subsys_initcall(channel_subsystem_init);
1004 static int css_settle(struct device_driver *drv, void *unused)
1006 struct css_driver *cssdrv = to_cssdriver(drv);
1014 * Wait for the initialization of devices to finish, to make sure we are
1015 * done with our setup if the search for the root device starts.
1017 static int __init channel_subsystem_init_sync(void)
1019 /* Start initial subchannel evaluation. */
1020 css_schedule_eval_all();
1021 /* Wait for the evaluation of subchannels to finish. */
1022 wait_event(css_eval_wq, atomic_read(&css_eval_scheduled) == 0);
1023 /* Wait for the subchannel type specific initialization to finish */
1024 return bus_for_each_drv(&css_bus_type, NULL, NULL, css_settle);
1026 subsys_initcall_sync(channel_subsystem_init_sync);
1028 int sch_is_pseudo_sch(struct subchannel *sch)
1030 return sch == to_css(sch->dev.parent)->pseudo_subchannel;
1033 static int css_bus_match(struct device *dev, struct device_driver *drv)
1035 struct subchannel *sch = to_subchannel(dev);
1036 struct css_driver *driver = to_cssdriver(drv);
1037 struct css_device_id *id;
1039 for (id = driver->subchannel_type; id->match_flags; id++) {
1040 if (sch->st == id->type)
1047 static int css_probe(struct device *dev)
1049 struct subchannel *sch;
1052 sch = to_subchannel(dev);
1053 sch->driver = to_cssdriver(dev->driver);
1054 ret = sch->driver->probe ? sch->driver->probe(sch) : 0;
1060 static int css_remove(struct device *dev)
1062 struct subchannel *sch;
1065 sch = to_subchannel(dev);
1066 ret = sch->driver->remove ? sch->driver->remove(sch) : 0;
1071 static void css_shutdown(struct device *dev)
1073 struct subchannel *sch;
1075 sch = to_subchannel(dev);
1076 if (sch->driver && sch->driver->shutdown)
1077 sch->driver->shutdown(sch);
1080 static int css_uevent(struct device *dev, struct kobj_uevent_env *env)
1082 struct subchannel *sch = to_subchannel(dev);
1085 ret = add_uevent_var(env, "ST=%01X", sch->st);
1088 ret = add_uevent_var(env, "MODALIAS=css:t%01X", sch->st);
1092 static int css_pm_prepare(struct device *dev)
1094 struct subchannel *sch = to_subchannel(dev);
1095 struct css_driver *drv;
1097 if (mutex_is_locked(&sch->reg_mutex))
1099 if (!sch->dev.driver)
1101 drv = to_cssdriver(sch->dev.driver);
1102 /* Notify drivers that they may not register children. */
1103 return drv->prepare ? drv->prepare(sch) : 0;
1106 static void css_pm_complete(struct device *dev)
1108 struct subchannel *sch = to_subchannel(dev);
1109 struct css_driver *drv;
1111 if (!sch->dev.driver)
1113 drv = to_cssdriver(sch->dev.driver);
1118 static int css_pm_freeze(struct device *dev)
1120 struct subchannel *sch = to_subchannel(dev);
1121 struct css_driver *drv;
1123 if (!sch->dev.driver)
1125 drv = to_cssdriver(sch->dev.driver);
1126 return drv->freeze ? drv->freeze(sch) : 0;
1129 static int css_pm_thaw(struct device *dev)
1131 struct subchannel *sch = to_subchannel(dev);
1132 struct css_driver *drv;
1134 if (!sch->dev.driver)
1136 drv = to_cssdriver(sch->dev.driver);
1137 return drv->thaw ? drv->thaw(sch) : 0;
1140 static int css_pm_restore(struct device *dev)
1142 struct subchannel *sch = to_subchannel(dev);
1143 struct css_driver *drv;
1145 if (!sch->dev.driver)
1147 drv = to_cssdriver(sch->dev.driver);
1148 return drv->restore ? drv->restore(sch) : 0;
1151 static struct dev_pm_ops css_pm_ops = {
1152 .prepare = css_pm_prepare,
1153 .complete = css_pm_complete,
1154 .freeze = css_pm_freeze,
1155 .thaw = css_pm_thaw,
1156 .restore = css_pm_restore,
1159 struct bus_type css_bus_type = {
1161 .match = css_bus_match,
1163 .remove = css_remove,
1164 .shutdown = css_shutdown,
1165 .uevent = css_uevent,
1170 * css_driver_register - register a css driver
1171 * @cdrv: css driver to register
1173 * This is mainly a wrapper around driver_register that sets name
1174 * and bus_type in the embedded struct device_driver correctly.
1176 int css_driver_register(struct css_driver *cdrv)
1178 cdrv->drv.name = cdrv->name;
1179 cdrv->drv.bus = &css_bus_type;
1180 cdrv->drv.owner = cdrv->owner;
1181 return driver_register(&cdrv->drv);
1183 EXPORT_SYMBOL_GPL(css_driver_register);
1186 * css_driver_unregister - unregister a css driver
1187 * @cdrv: css driver to unregister
1189 * This is a wrapper around driver_unregister.
1191 void css_driver_unregister(struct css_driver *cdrv)
1193 driver_unregister(&cdrv->drv);
1195 EXPORT_SYMBOL_GPL(css_driver_unregister);
1197 MODULE_LICENSE("GPL");
1198 EXPORT_SYMBOL(css_bus_type);