2 * drivers/base/power/domain.c - Common code related to device power domains.
4 * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
6 * This file is released under the GPLv2.
9 #include <linux/delay.h>
10 #include <linux/kernel.h>
12 #include <linux/platform_device.h>
13 #include <linux/pm_runtime.h>
14 #include <linux/pm_domain.h>
15 #include <linux/pm_qos.h>
16 #include <linux/pm_clock.h>
17 #include <linux/slab.h>
18 #include <linux/err.h>
19 #include <linux/sched.h>
20 #include <linux/suspend.h>
21 #include <linux/export.h>
23 #define GENPD_RETRY_MAX_MS 250 /* Approximate */
25 #define GENPD_DEV_CALLBACK(genpd, type, callback, dev) \
27 type (*__routine)(struct device *__d); \
28 type __ret = (type)0; \
30 __routine = genpd->dev_ops.callback; \
32 __ret = __routine(dev); \
37 static LIST_HEAD(gpd_list);
38 static DEFINE_MUTEX(gpd_list_lock);
41 * Get the generic PM domain for a particular struct device.
42 * This validates the struct device pointer, the PM domain pointer,
43 * and checks that the PM domain pointer is a real generic PM domain.
44 * Any failure results in NULL being returned.
46 struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
48 struct generic_pm_domain *genpd = NULL, *gpd;
50 if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
53 mutex_lock(&gpd_list_lock);
54 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
55 if (&gpd->domain == dev->pm_domain) {
60 mutex_unlock(&gpd_list_lock);
66 * This should only be used where we are certain that the pm_domain
67 * attached to the device is a genpd domain.
69 static struct generic_pm_domain *dev_to_genpd(struct device *dev)
71 if (IS_ERR_OR_NULL(dev->pm_domain))
72 return ERR_PTR(-EINVAL);
74 return pd_to_genpd(dev->pm_domain);
77 static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
79 return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
82 static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
84 return GENPD_DEV_CALLBACK(genpd, int, start, dev);
87 static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
91 if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
92 ret = !!atomic_dec_and_test(&genpd->sd_count);
97 static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
99 atomic_inc(&genpd->sd_count);
100 smp_mb__after_atomic();
103 static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
109 if (!genpd->power_on)
113 return genpd->power_on(genpd);
115 time_start = ktime_get();
116 ret = genpd->power_on(genpd);
120 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
121 if (elapsed_ns <= genpd->power_on_latency_ns)
124 genpd->power_on_latency_ns = elapsed_ns;
125 genpd->max_off_time_changed = true;
126 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
127 genpd->name, "on", elapsed_ns);
132 static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
138 if (!genpd->power_off)
142 return genpd->power_off(genpd);
144 time_start = ktime_get();
145 ret = genpd->power_off(genpd);
149 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
150 if (elapsed_ns <= genpd->power_off_latency_ns)
153 genpd->power_off_latency_ns = elapsed_ns;
154 genpd->max_off_time_changed = true;
155 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
156 genpd->name, "off", elapsed_ns);
162 * genpd_queue_power_off_work - Queue up the execution of genpd_poweroff().
163 * @genpd: PM domait to power off.
165 * Queue up the execution of genpd_poweroff() unless it's already been done
168 static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
170 queue_work(pm_wq, &genpd->power_off_work);
173 static int genpd_poweron(struct generic_pm_domain *genpd);
176 * __genpd_poweron - Restore power to a given PM domain and its masters.
177 * @genpd: PM domain to power up.
179 * Restore power to @genpd and all of its masters so that it is possible to
180 * resume a device belonging to it.
182 static int __genpd_poweron(struct generic_pm_domain *genpd)
184 struct gpd_link *link;
187 if (genpd->status == GPD_STATE_ACTIVE
188 || (genpd->prepared_count > 0 && genpd->suspend_power_off))
192 * The list is guaranteed not to change while the loop below is being
193 * executed, unless one of the masters' .power_on() callbacks fiddles
196 list_for_each_entry(link, &genpd->slave_links, slave_node) {
197 genpd_sd_counter_inc(link->master);
199 ret = genpd_poweron(link->master);
201 genpd_sd_counter_dec(link->master);
206 ret = genpd_power_on(genpd, true);
210 genpd->status = GPD_STATE_ACTIVE;
214 list_for_each_entry_continue_reverse(link,
217 genpd_sd_counter_dec(link->master);
218 genpd_queue_power_off_work(link->master);
225 * genpd_poweron - Restore power to a given PM domain and its masters.
226 * @genpd: PM domain to power up.
228 static int genpd_poweron(struct generic_pm_domain *genpd)
232 mutex_lock(&genpd->lock);
233 ret = __genpd_poweron(genpd);
234 mutex_unlock(&genpd->lock);
238 static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
240 return GENPD_DEV_CALLBACK(genpd, int, save_state, dev);
243 static int genpd_restore_dev(struct generic_pm_domain *genpd,
246 return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev);
249 static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
250 unsigned long val, void *ptr)
252 struct generic_pm_domain_data *gpd_data;
255 gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
256 dev = gpd_data->base.dev;
259 struct generic_pm_domain *genpd;
260 struct pm_domain_data *pdd;
262 spin_lock_irq(&dev->power.lock);
264 pdd = dev->power.subsys_data ?
265 dev->power.subsys_data->domain_data : NULL;
266 if (pdd && pdd->dev) {
267 to_gpd_data(pdd)->td.constraint_changed = true;
268 genpd = dev_to_genpd(dev);
270 genpd = ERR_PTR(-ENODATA);
273 spin_unlock_irq(&dev->power.lock);
275 if (!IS_ERR(genpd)) {
276 mutex_lock(&genpd->lock);
277 genpd->max_off_time_changed = true;
278 mutex_unlock(&genpd->lock);
282 if (!dev || dev->power.ignore_children)
290 * genpd_poweroff - Remove power from a given PM domain.
291 * @genpd: PM domain to power down.
292 * @is_async: PM domain is powered down from a scheduled work
294 * If all of the @genpd's devices have been suspended and all of its subdomains
295 * have been powered down, remove power from @genpd.
297 static int genpd_poweroff(struct generic_pm_domain *genpd, bool is_async)
299 struct pm_domain_data *pdd;
300 struct gpd_link *link;
301 unsigned int not_suspended = 0;
304 * Do not try to power off the domain in the following situations:
305 * (1) The domain is already in the "power off" state.
306 * (2) System suspend is in progress.
308 if (genpd->status == GPD_STATE_POWER_OFF
309 || genpd->prepared_count > 0)
312 if (atomic_read(&genpd->sd_count) > 0)
315 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
316 enum pm_qos_flags_status stat;
318 stat = dev_pm_qos_flags(pdd->dev,
319 PM_QOS_FLAG_NO_POWER_OFF
320 | PM_QOS_FLAG_REMOTE_WAKEUP);
321 if (stat > PM_QOS_FLAGS_NONE)
324 if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
325 || pdd->dev->power.irq_safe))
329 if (not_suspended > 1 || (not_suspended == 1 && is_async))
332 if (genpd->gov && genpd->gov->power_down_ok) {
333 if (!genpd->gov->power_down_ok(&genpd->domain))
337 if (genpd->power_off) {
340 if (atomic_read(&genpd->sd_count) > 0)
344 * If sd_count > 0 at this point, one of the subdomains hasn't
345 * managed to call genpd_poweron() for the master yet after
346 * incrementing it. In that case genpd_poweron() will wait
347 * for us to drop the lock, so we can call .power_off() and let
348 * the genpd_poweron() restore power for us (this shouldn't
349 * happen very often).
351 ret = genpd_power_off(genpd, true);
356 genpd->status = GPD_STATE_POWER_OFF;
358 list_for_each_entry(link, &genpd->slave_links, slave_node) {
359 genpd_sd_counter_dec(link->master);
360 genpd_queue_power_off_work(link->master);
367 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
368 * @work: Work structure used for scheduling the execution of this function.
370 static void genpd_power_off_work_fn(struct work_struct *work)
372 struct generic_pm_domain *genpd;
374 genpd = container_of(work, struct generic_pm_domain, power_off_work);
376 mutex_lock(&genpd->lock);
377 genpd_poweroff(genpd, true);
378 mutex_unlock(&genpd->lock);
382 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
383 * @dev: Device to suspend.
385 * Carry out a runtime suspend of a device under the assumption that its
386 * pm_domain field points to the domain member of an object of type
387 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
389 static int pm_genpd_runtime_suspend(struct device *dev)
391 struct generic_pm_domain *genpd;
392 bool (*stop_ok)(struct device *__dev);
393 struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
398 dev_dbg(dev, "%s()\n", __func__);
400 genpd = dev_to_genpd(dev);
404 stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
405 if (stop_ok && !stop_ok(dev))
408 /* Measure suspend latency. */
409 time_start = ktime_get();
411 ret = genpd_save_dev(genpd, dev);
415 ret = genpd_stop_dev(genpd, dev);
417 genpd_restore_dev(genpd, dev);
421 /* Update suspend latency value if the measured time exceeds it. */
422 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
423 if (elapsed_ns > td->suspend_latency_ns) {
424 td->suspend_latency_ns = elapsed_ns;
425 dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
427 genpd->max_off_time_changed = true;
428 td->constraint_changed = true;
432 * If power.irq_safe is set, this routine will be run with interrupts
433 * off, so it can't use mutexes.
435 if (dev->power.irq_safe)
438 mutex_lock(&genpd->lock);
439 genpd_poweroff(genpd, false);
440 mutex_unlock(&genpd->lock);
446 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
447 * @dev: Device to resume.
449 * Carry out a runtime resume of a device under the assumption that its
450 * pm_domain field points to the domain member of an object of type
451 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
453 static int pm_genpd_runtime_resume(struct device *dev)
455 struct generic_pm_domain *genpd;
456 struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
462 dev_dbg(dev, "%s()\n", __func__);
464 genpd = dev_to_genpd(dev);
468 /* If power.irq_safe, the PM domain is never powered off. */
469 if (dev->power.irq_safe) {
474 mutex_lock(&genpd->lock);
475 ret = __genpd_poweron(genpd);
476 mutex_unlock(&genpd->lock);
482 /* Measure resume latency. */
484 time_start = ktime_get();
486 genpd_start_dev(genpd, dev);
487 genpd_restore_dev(genpd, dev);
489 /* Update resume latency value if the measured time exceeds it. */
491 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
492 if (elapsed_ns > td->resume_latency_ns) {
493 td->resume_latency_ns = elapsed_ns;
494 dev_dbg(dev, "resume latency exceeded, %lld ns\n",
496 genpd->max_off_time_changed = true;
497 td->constraint_changed = true;
504 static bool pd_ignore_unused;
505 static int __init pd_ignore_unused_setup(char *__unused)
507 pd_ignore_unused = true;
510 __setup("pd_ignore_unused", pd_ignore_unused_setup);
513 * genpd_poweroff_unused - Power off all PM domains with no devices in use.
515 static int __init genpd_poweroff_unused(void)
517 struct generic_pm_domain *genpd;
519 if (pd_ignore_unused) {
520 pr_warn("genpd: Not disabling unused power domains\n");
524 mutex_lock(&gpd_list_lock);
526 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
527 genpd_queue_power_off_work(genpd);
529 mutex_unlock(&gpd_list_lock);
533 late_initcall(genpd_poweroff_unused);
535 #ifdef CONFIG_PM_SLEEP
538 * pm_genpd_present - Check if the given PM domain has been initialized.
539 * @genpd: PM domain to check.
541 static bool pm_genpd_present(const struct generic_pm_domain *genpd)
543 const struct generic_pm_domain *gpd;
545 if (IS_ERR_OR_NULL(genpd))
548 list_for_each_entry(gpd, &gpd_list, gpd_list_node)
555 static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
558 return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
562 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
563 * @genpd: PM domain to power off, if possible.
564 * @timed: True if latency measurements are allowed.
566 * Check if the given PM domain can be powered off (during system suspend or
567 * hibernation) and do that if so. Also, in that case propagate to its masters.
569 * This function is only called in "noirq" and "syscore" stages of system power
570 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
571 * executed sequentially, so it is guaranteed that it will never run twice in
574 static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
577 struct gpd_link *link;
579 if (genpd->status == GPD_STATE_POWER_OFF)
582 if (genpd->suspended_count != genpd->device_count
583 || atomic_read(&genpd->sd_count) > 0)
586 genpd_power_off(genpd, timed);
588 genpd->status = GPD_STATE_POWER_OFF;
590 list_for_each_entry(link, &genpd->slave_links, slave_node) {
591 genpd_sd_counter_dec(link->master);
592 pm_genpd_sync_poweroff(link->master, timed);
597 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
598 * @genpd: PM domain to power on.
599 * @timed: True if latency measurements are allowed.
601 * This function is only called in "noirq" and "syscore" stages of system power
602 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
603 * executed sequentially, so it is guaranteed that it will never run twice in
606 static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
609 struct gpd_link *link;
611 if (genpd->status == GPD_STATE_ACTIVE)
614 list_for_each_entry(link, &genpd->slave_links, slave_node) {
615 pm_genpd_sync_poweron(link->master, timed);
616 genpd_sd_counter_inc(link->master);
619 genpd_power_on(genpd, timed);
621 genpd->status = GPD_STATE_ACTIVE;
625 * resume_needed - Check whether to resume a device before system suspend.
626 * @dev: Device to check.
627 * @genpd: PM domain the device belongs to.
629 * There are two cases in which a device that can wake up the system from sleep
630 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
631 * to wake up the system and it has to remain active for this purpose while the
632 * system is in the sleep state and (2) if the device is not enabled to wake up
633 * the system from sleep states and it generally doesn't generate wakeup signals
634 * by itself (those signals are generated on its behalf by other parts of the
635 * system). In the latter case it may be necessary to reconfigure the device's
636 * wakeup settings during system suspend, because it may have been set up to
637 * signal remote wakeup from the system's working state as needed by runtime PM.
638 * Return 'true' in either of the above cases.
640 static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
644 if (!device_can_wakeup(dev))
647 active_wakeup = genpd_dev_active_wakeup(genpd, dev);
648 return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
652 * pm_genpd_prepare - Start power transition of a device in a PM domain.
653 * @dev: Device to start the transition of.
655 * Start a power transition of a device (during a system-wide power transition)
656 * under the assumption that its pm_domain field points to the domain member of
657 * an object of type struct generic_pm_domain representing a PM domain
658 * consisting of I/O devices.
660 static int pm_genpd_prepare(struct device *dev)
662 struct generic_pm_domain *genpd;
665 dev_dbg(dev, "%s()\n", __func__);
667 genpd = dev_to_genpd(dev);
672 * If a wakeup request is pending for the device, it should be woken up
673 * at this point and a system wakeup event should be reported if it's
674 * set up to wake up the system from sleep states.
676 pm_runtime_get_noresume(dev);
677 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
678 pm_wakeup_event(dev, 0);
680 if (pm_wakeup_pending()) {
685 if (resume_needed(dev, genpd))
686 pm_runtime_resume(dev);
688 mutex_lock(&genpd->lock);
690 if (genpd->prepared_count++ == 0) {
691 genpd->suspended_count = 0;
692 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
695 mutex_unlock(&genpd->lock);
697 if (genpd->suspend_power_off) {
698 pm_runtime_put_noidle(dev);
703 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
704 * so genpd_poweron() will return immediately, but if the device
705 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
706 * to make it operational.
708 pm_runtime_resume(dev);
709 __pm_runtime_disable(dev, false);
711 ret = pm_generic_prepare(dev);
713 mutex_lock(&genpd->lock);
715 if (--genpd->prepared_count == 0)
716 genpd->suspend_power_off = false;
718 mutex_unlock(&genpd->lock);
719 pm_runtime_enable(dev);
727 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
728 * @dev: Device to suspend.
730 * Suspend a device under the assumption that its pm_domain field points to the
731 * domain member of an object of type struct generic_pm_domain representing
732 * a PM domain consisting of I/O devices.
734 static int pm_genpd_suspend(struct device *dev)
736 struct generic_pm_domain *genpd;
738 dev_dbg(dev, "%s()\n", __func__);
740 genpd = dev_to_genpd(dev);
744 return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
748 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
749 * @dev: Device to suspend.
751 * Carry out a late suspend of a device under the assumption that its
752 * pm_domain field points to the domain member of an object of type
753 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
755 static int pm_genpd_suspend_late(struct device *dev)
757 struct generic_pm_domain *genpd;
759 dev_dbg(dev, "%s()\n", __func__);
761 genpd = dev_to_genpd(dev);
765 return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
769 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
770 * @dev: Device to suspend.
772 * Stop the device and remove power from the domain if all devices in it have
775 static int pm_genpd_suspend_noirq(struct device *dev)
777 struct generic_pm_domain *genpd;
779 dev_dbg(dev, "%s()\n", __func__);
781 genpd = dev_to_genpd(dev);
785 if (genpd->suspend_power_off
786 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
789 genpd_stop_dev(genpd, dev);
792 * Since all of the "noirq" callbacks are executed sequentially, it is
793 * guaranteed that this function will never run twice in parallel for
794 * the same PM domain, so it is not necessary to use locking here.
796 genpd->suspended_count++;
797 pm_genpd_sync_poweroff(genpd, true);
803 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
804 * @dev: Device to resume.
806 * Restore power to the device's PM domain, if necessary, and start the device.
808 static int pm_genpd_resume_noirq(struct device *dev)
810 struct generic_pm_domain *genpd;
812 dev_dbg(dev, "%s()\n", __func__);
814 genpd = dev_to_genpd(dev);
818 if (genpd->suspend_power_off
819 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
823 * Since all of the "noirq" callbacks are executed sequentially, it is
824 * guaranteed that this function will never run twice in parallel for
825 * the same PM domain, so it is not necessary to use locking here.
827 pm_genpd_sync_poweron(genpd, true);
828 genpd->suspended_count--;
830 return genpd_start_dev(genpd, dev);
834 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
835 * @dev: Device to resume.
837 * Carry out an early resume of a device under the assumption that its
838 * pm_domain field points to the domain member of an object of type
839 * struct generic_pm_domain representing a power domain consisting of I/O
842 static int pm_genpd_resume_early(struct device *dev)
844 struct generic_pm_domain *genpd;
846 dev_dbg(dev, "%s()\n", __func__);
848 genpd = dev_to_genpd(dev);
852 return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
856 * pm_genpd_resume - Resume of device in an I/O PM domain.
857 * @dev: Device to resume.
859 * Resume a device under the assumption that its pm_domain field points to the
860 * domain member of an object of type struct generic_pm_domain representing
861 * a power domain consisting of I/O devices.
863 static int pm_genpd_resume(struct device *dev)
865 struct generic_pm_domain *genpd;
867 dev_dbg(dev, "%s()\n", __func__);
869 genpd = dev_to_genpd(dev);
873 return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
877 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
878 * @dev: Device to freeze.
880 * Freeze a device under the assumption that its pm_domain field points to the
881 * domain member of an object of type struct generic_pm_domain representing
882 * a power domain consisting of I/O devices.
884 static int pm_genpd_freeze(struct device *dev)
886 struct generic_pm_domain *genpd;
888 dev_dbg(dev, "%s()\n", __func__);
890 genpd = dev_to_genpd(dev);
894 return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
898 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
899 * @dev: Device to freeze.
901 * Carry out a late freeze of a device under the assumption that its
902 * pm_domain field points to the domain member of an object of type
903 * struct generic_pm_domain representing a power domain consisting of I/O
906 static int pm_genpd_freeze_late(struct device *dev)
908 struct generic_pm_domain *genpd;
910 dev_dbg(dev, "%s()\n", __func__);
912 genpd = dev_to_genpd(dev);
916 return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
920 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
921 * @dev: Device to freeze.
923 * Carry out a late freeze of a device under the assumption that its
924 * pm_domain field points to the domain member of an object of type
925 * struct generic_pm_domain representing a power domain consisting of I/O
928 static int pm_genpd_freeze_noirq(struct device *dev)
930 struct generic_pm_domain *genpd;
932 dev_dbg(dev, "%s()\n", __func__);
934 genpd = dev_to_genpd(dev);
938 return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
942 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
943 * @dev: Device to thaw.
945 * Start the device, unless power has been removed from the domain already
946 * before the system transition.
948 static int pm_genpd_thaw_noirq(struct device *dev)
950 struct generic_pm_domain *genpd;
952 dev_dbg(dev, "%s()\n", __func__);
954 genpd = dev_to_genpd(dev);
958 return genpd->suspend_power_off ?
959 0 : genpd_start_dev(genpd, dev);
963 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
964 * @dev: Device to thaw.
966 * Carry out an early thaw of a device under the assumption that its
967 * pm_domain field points to the domain member of an object of type
968 * struct generic_pm_domain representing a power domain consisting of I/O
971 static int pm_genpd_thaw_early(struct device *dev)
973 struct generic_pm_domain *genpd;
975 dev_dbg(dev, "%s()\n", __func__);
977 genpd = dev_to_genpd(dev);
981 return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
985 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
986 * @dev: Device to thaw.
988 * Thaw a device under the assumption that its pm_domain field points to the
989 * domain member of an object of type struct generic_pm_domain representing
990 * a power domain consisting of I/O devices.
992 static int pm_genpd_thaw(struct device *dev)
994 struct generic_pm_domain *genpd;
996 dev_dbg(dev, "%s()\n", __func__);
998 genpd = dev_to_genpd(dev);
1002 return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
1006 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1007 * @dev: Device to resume.
1009 * Make sure the domain will be in the same power state as before the
1010 * hibernation the system is resuming from and start the device if necessary.
1012 static int pm_genpd_restore_noirq(struct device *dev)
1014 struct generic_pm_domain *genpd;
1016 dev_dbg(dev, "%s()\n", __func__);
1018 genpd = dev_to_genpd(dev);
1023 * Since all of the "noirq" callbacks are executed sequentially, it is
1024 * guaranteed that this function will never run twice in parallel for
1025 * the same PM domain, so it is not necessary to use locking here.
1027 * At this point suspended_count == 0 means we are being run for the
1028 * first time for the given domain in the present cycle.
1030 if (genpd->suspended_count++ == 0) {
1032 * The boot kernel might put the domain into arbitrary state,
1033 * so make it appear as powered off to pm_genpd_sync_poweron(),
1034 * so that it tries to power it on in case it was really off.
1036 genpd->status = GPD_STATE_POWER_OFF;
1037 if (genpd->suspend_power_off) {
1039 * If the domain was off before the hibernation, make
1040 * sure it will be off going forward.
1042 genpd_power_off(genpd, true);
1048 if (genpd->suspend_power_off)
1051 pm_genpd_sync_poweron(genpd, true);
1053 return genpd_start_dev(genpd, dev);
1057 * pm_genpd_complete - Complete power transition of a device in a power domain.
1058 * @dev: Device to complete the transition of.
1060 * Complete a power transition of a device (during a system-wide power
1061 * transition) under the assumption that its pm_domain field points to the
1062 * domain member of an object of type struct generic_pm_domain representing
1063 * a power domain consisting of I/O devices.
1065 static void pm_genpd_complete(struct device *dev)
1067 struct generic_pm_domain *genpd;
1070 dev_dbg(dev, "%s()\n", __func__);
1072 genpd = dev_to_genpd(dev);
1076 mutex_lock(&genpd->lock);
1078 run_complete = !genpd->suspend_power_off;
1079 if (--genpd->prepared_count == 0)
1080 genpd->suspend_power_off = false;
1082 mutex_unlock(&genpd->lock);
1085 pm_generic_complete(dev);
1086 pm_runtime_set_active(dev);
1087 pm_runtime_enable(dev);
1088 pm_request_idle(dev);
1093 * genpd_syscore_switch - Switch power during system core suspend or resume.
1094 * @dev: Device that normally is marked as "always on" to switch power for.
1096 * This routine may only be called during the system core (syscore) suspend or
1097 * resume phase for devices whose "always on" flags are set.
1099 static void genpd_syscore_switch(struct device *dev, bool suspend)
1101 struct generic_pm_domain *genpd;
1103 genpd = dev_to_genpd(dev);
1104 if (!pm_genpd_present(genpd))
1108 genpd->suspended_count++;
1109 pm_genpd_sync_poweroff(genpd, false);
1111 pm_genpd_sync_poweron(genpd, false);
1112 genpd->suspended_count--;
1116 void pm_genpd_syscore_poweroff(struct device *dev)
1118 genpd_syscore_switch(dev, true);
1120 EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
1122 void pm_genpd_syscore_poweron(struct device *dev)
1124 genpd_syscore_switch(dev, false);
1126 EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1128 #else /* !CONFIG_PM_SLEEP */
1130 #define pm_genpd_prepare NULL
1131 #define pm_genpd_suspend NULL
1132 #define pm_genpd_suspend_late NULL
1133 #define pm_genpd_suspend_noirq NULL
1134 #define pm_genpd_resume_early NULL
1135 #define pm_genpd_resume_noirq NULL
1136 #define pm_genpd_resume NULL
1137 #define pm_genpd_freeze NULL
1138 #define pm_genpd_freeze_late NULL
1139 #define pm_genpd_freeze_noirq NULL
1140 #define pm_genpd_thaw_early NULL
1141 #define pm_genpd_thaw_noirq NULL
1142 #define pm_genpd_thaw NULL
1143 #define pm_genpd_restore_noirq NULL
1144 #define pm_genpd_complete NULL
1146 #endif /* CONFIG_PM_SLEEP */
1148 static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1149 struct generic_pm_domain *genpd,
1150 struct gpd_timing_data *td)
1152 struct generic_pm_domain_data *gpd_data;
1155 ret = dev_pm_get_subsys_data(dev);
1157 return ERR_PTR(ret);
1159 gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1168 gpd_data->base.dev = dev;
1169 gpd_data->td.constraint_changed = true;
1170 gpd_data->td.effective_constraint_ns = -1;
1171 gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1173 spin_lock_irq(&dev->power.lock);
1175 if (dev->power.subsys_data->domain_data) {
1180 dev->power.subsys_data->domain_data = &gpd_data->base;
1181 dev->pm_domain = &genpd->domain;
1183 spin_unlock_irq(&dev->power.lock);
1188 spin_unlock_irq(&dev->power.lock);
1191 dev_pm_put_subsys_data(dev);
1192 return ERR_PTR(ret);
1195 static void genpd_free_dev_data(struct device *dev,
1196 struct generic_pm_domain_data *gpd_data)
1198 spin_lock_irq(&dev->power.lock);
1200 dev->pm_domain = NULL;
1201 dev->power.subsys_data->domain_data = NULL;
1203 spin_unlock_irq(&dev->power.lock);
1206 dev_pm_put_subsys_data(dev);
1210 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1211 * @genpd: PM domain to add the device to.
1212 * @dev: Device to be added.
1213 * @td: Set of PM QoS timing parameters to attach to the device.
1215 int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1216 struct gpd_timing_data *td)
1218 struct generic_pm_domain_data *gpd_data;
1221 dev_dbg(dev, "%s()\n", __func__);
1223 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1226 gpd_data = genpd_alloc_dev_data(dev, genpd, td);
1227 if (IS_ERR(gpd_data))
1228 return PTR_ERR(gpd_data);
1230 mutex_lock(&genpd->lock);
1232 if (genpd->prepared_count > 0) {
1237 ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1241 genpd->device_count++;
1242 genpd->max_off_time_changed = true;
1244 list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1247 mutex_unlock(&genpd->lock);
1250 genpd_free_dev_data(dev, gpd_data);
1252 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1258 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1259 * @genpd: PM domain to remove the device from.
1260 * @dev: Device to be removed.
1262 int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1265 struct generic_pm_domain_data *gpd_data;
1266 struct pm_domain_data *pdd;
1269 dev_dbg(dev, "%s()\n", __func__);
1271 if (!genpd || genpd != pm_genpd_lookup_dev(dev))
1274 /* The above validation also means we have existing domain_data. */
1275 pdd = dev->power.subsys_data->domain_data;
1276 gpd_data = to_gpd_data(pdd);
1277 dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1279 mutex_lock(&genpd->lock);
1281 if (genpd->prepared_count > 0) {
1286 genpd->device_count--;
1287 genpd->max_off_time_changed = true;
1289 if (genpd->detach_dev)
1290 genpd->detach_dev(genpd, dev);
1292 list_del_init(&pdd->list_node);
1294 mutex_unlock(&genpd->lock);
1296 genpd_free_dev_data(dev, gpd_data);
1301 mutex_unlock(&genpd->lock);
1302 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1308 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1309 * @genpd: Master PM domain to add the subdomain to.
1310 * @subdomain: Subdomain to be added.
1312 int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1313 struct generic_pm_domain *subdomain)
1315 struct gpd_link *link;
1318 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1319 || genpd == subdomain)
1322 mutex_lock(&genpd->lock);
1323 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1325 if (genpd->status == GPD_STATE_POWER_OFF
1326 && subdomain->status != GPD_STATE_POWER_OFF) {
1331 list_for_each_entry(link, &genpd->master_links, master_node) {
1332 if (link->slave == subdomain && link->master == genpd) {
1338 link = kzalloc(sizeof(*link), GFP_KERNEL);
1343 link->master = genpd;
1344 list_add_tail(&link->master_node, &genpd->master_links);
1345 link->slave = subdomain;
1346 list_add_tail(&link->slave_node, &subdomain->slave_links);
1347 if (subdomain->status != GPD_STATE_POWER_OFF)
1348 genpd_sd_counter_inc(genpd);
1351 mutex_unlock(&subdomain->lock);
1352 mutex_unlock(&genpd->lock);
1356 EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
1359 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1360 * @genpd: Master PM domain to remove the subdomain from.
1361 * @subdomain: Subdomain to be removed.
1363 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1364 struct generic_pm_domain *subdomain)
1366 struct gpd_link *link;
1369 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1372 mutex_lock(&genpd->lock);
1374 if (!list_empty(&subdomain->slave_links) || subdomain->device_count) {
1375 pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
1381 list_for_each_entry(link, &genpd->master_links, master_node) {
1382 if (link->slave != subdomain)
1385 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1387 list_del(&link->master_node);
1388 list_del(&link->slave_node);
1390 if (subdomain->status != GPD_STATE_POWER_OFF)
1391 genpd_sd_counter_dec(genpd);
1393 mutex_unlock(&subdomain->lock);
1400 mutex_unlock(&genpd->lock);
1404 EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
1406 /* Default device callbacks for generic PM domains. */
1409 * pm_genpd_default_save_state - Default "save device state" for PM domains.
1410 * @dev: Device to handle.
1412 static int pm_genpd_default_save_state(struct device *dev)
1414 int (*cb)(struct device *__dev);
1416 if (dev->type && dev->type->pm)
1417 cb = dev->type->pm->runtime_suspend;
1418 else if (dev->class && dev->class->pm)
1419 cb = dev->class->pm->runtime_suspend;
1420 else if (dev->bus && dev->bus->pm)
1421 cb = dev->bus->pm->runtime_suspend;
1425 if (!cb && dev->driver && dev->driver->pm)
1426 cb = dev->driver->pm->runtime_suspend;
1428 return cb ? cb(dev) : 0;
1432 * pm_genpd_default_restore_state - Default PM domains "restore device state".
1433 * @dev: Device to handle.
1435 static int pm_genpd_default_restore_state(struct device *dev)
1437 int (*cb)(struct device *__dev);
1439 if (dev->type && dev->type->pm)
1440 cb = dev->type->pm->runtime_resume;
1441 else if (dev->class && dev->class->pm)
1442 cb = dev->class->pm->runtime_resume;
1443 else if (dev->bus && dev->bus->pm)
1444 cb = dev->bus->pm->runtime_resume;
1448 if (!cb && dev->driver && dev->driver->pm)
1449 cb = dev->driver->pm->runtime_resume;
1451 return cb ? cb(dev) : 0;
1455 * pm_genpd_init - Initialize a generic I/O PM domain object.
1456 * @genpd: PM domain object to initialize.
1457 * @gov: PM domain governor to associate with the domain (may be NULL).
1458 * @is_off: Initial value of the domain's power_is_off field.
1460 void pm_genpd_init(struct generic_pm_domain *genpd,
1461 struct dev_power_governor *gov, bool is_off)
1463 if (IS_ERR_OR_NULL(genpd))
1466 INIT_LIST_HEAD(&genpd->master_links);
1467 INIT_LIST_HEAD(&genpd->slave_links);
1468 INIT_LIST_HEAD(&genpd->dev_list);
1469 mutex_init(&genpd->lock);
1471 INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
1472 atomic_set(&genpd->sd_count, 0);
1473 genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
1474 genpd->device_count = 0;
1475 genpd->max_off_time_ns = -1;
1476 genpd->max_off_time_changed = true;
1477 genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
1478 genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
1479 genpd->domain.ops.prepare = pm_genpd_prepare;
1480 genpd->domain.ops.suspend = pm_genpd_suspend;
1481 genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
1482 genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
1483 genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
1484 genpd->domain.ops.resume_early = pm_genpd_resume_early;
1485 genpd->domain.ops.resume = pm_genpd_resume;
1486 genpd->domain.ops.freeze = pm_genpd_freeze;
1487 genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
1488 genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
1489 genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
1490 genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
1491 genpd->domain.ops.thaw = pm_genpd_thaw;
1492 genpd->domain.ops.poweroff = pm_genpd_suspend;
1493 genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
1494 genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
1495 genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
1496 genpd->domain.ops.restore_early = pm_genpd_resume_early;
1497 genpd->domain.ops.restore = pm_genpd_resume;
1498 genpd->domain.ops.complete = pm_genpd_complete;
1499 genpd->dev_ops.save_state = pm_genpd_default_save_state;
1500 genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
1502 if (genpd->flags & GENPD_FLAG_PM_CLK) {
1503 genpd->dev_ops.stop = pm_clk_suspend;
1504 genpd->dev_ops.start = pm_clk_resume;
1507 mutex_lock(&gpd_list_lock);
1508 list_add(&genpd->gpd_list_node, &gpd_list);
1509 mutex_unlock(&gpd_list_lock);
1511 EXPORT_SYMBOL_GPL(pm_genpd_init);
1513 #ifdef CONFIG_PM_GENERIC_DOMAINS_OF
1515 * Device Tree based PM domain providers.
1517 * The code below implements generic device tree based PM domain providers that
1518 * bind device tree nodes with generic PM domains registered in the system.
1520 * Any driver that registers generic PM domains and needs to support binding of
1521 * devices to these domains is supposed to register a PM domain provider, which
1522 * maps a PM domain specifier retrieved from the device tree to a PM domain.
1524 * Two simple mapping functions have been provided for convenience:
1525 * - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
1526 * - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
1531 * struct of_genpd_provider - PM domain provider registration structure
1532 * @link: Entry in global list of PM domain providers
1533 * @node: Pointer to device tree node of PM domain provider
1534 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
1536 * @data: context pointer to be passed into @xlate callback
1538 struct of_genpd_provider {
1539 struct list_head link;
1540 struct device_node *node;
1541 genpd_xlate_t xlate;
1545 /* List of registered PM domain providers. */
1546 static LIST_HEAD(of_genpd_providers);
1547 /* Mutex to protect the list above. */
1548 static DEFINE_MUTEX(of_genpd_mutex);
1551 * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
1552 * @genpdspec: OF phandle args to map into a PM domain
1553 * @data: xlate function private data - pointer to struct generic_pm_domain
1555 * This is a generic xlate function that can be used to model PM domains that
1556 * have their own device tree nodes. The private data of xlate function needs
1557 * to be a valid pointer to struct generic_pm_domain.
1559 struct generic_pm_domain *__of_genpd_xlate_simple(
1560 struct of_phandle_args *genpdspec,
1563 if (genpdspec->args_count != 0)
1564 return ERR_PTR(-EINVAL);
1567 EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
1570 * __of_genpd_xlate_onecell() - Xlate function using a single index.
1571 * @genpdspec: OF phandle args to map into a PM domain
1572 * @data: xlate function private data - pointer to struct genpd_onecell_data
1574 * This is a generic xlate function that can be used to model simple PM domain
1575 * controllers that have one device tree node and provide multiple PM domains.
1576 * A single cell is used as an index into an array of PM domains specified in
1577 * the genpd_onecell_data struct when registering the provider.
1579 struct generic_pm_domain *__of_genpd_xlate_onecell(
1580 struct of_phandle_args *genpdspec,
1583 struct genpd_onecell_data *genpd_data = data;
1584 unsigned int idx = genpdspec->args[0];
1586 if (genpdspec->args_count != 1)
1587 return ERR_PTR(-EINVAL);
1589 if (idx >= genpd_data->num_domains) {
1590 pr_err("%s: invalid domain index %u\n", __func__, idx);
1591 return ERR_PTR(-EINVAL);
1594 if (!genpd_data->domains[idx])
1595 return ERR_PTR(-ENOENT);
1597 return genpd_data->domains[idx];
1599 EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
1602 * __of_genpd_add_provider() - Register a PM domain provider for a node
1603 * @np: Device node pointer associated with the PM domain provider.
1604 * @xlate: Callback for decoding PM domain from phandle arguments.
1605 * @data: Context pointer for @xlate callback.
1607 int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
1610 struct of_genpd_provider *cp;
1612 cp = kzalloc(sizeof(*cp), GFP_KERNEL);
1616 cp->node = of_node_get(np);
1620 mutex_lock(&of_genpd_mutex);
1621 list_add(&cp->link, &of_genpd_providers);
1622 mutex_unlock(&of_genpd_mutex);
1623 pr_debug("Added domain provider from %s\n", np->full_name);
1627 EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
1630 * of_genpd_del_provider() - Remove a previously registered PM domain provider
1631 * @np: Device node pointer associated with the PM domain provider
1633 void of_genpd_del_provider(struct device_node *np)
1635 struct of_genpd_provider *cp;
1637 mutex_lock(&of_genpd_mutex);
1638 list_for_each_entry(cp, &of_genpd_providers, link) {
1639 if (cp->node == np) {
1640 list_del(&cp->link);
1641 of_node_put(cp->node);
1646 mutex_unlock(&of_genpd_mutex);
1648 EXPORT_SYMBOL_GPL(of_genpd_del_provider);
1651 * of_genpd_get_from_provider() - Look-up PM domain
1652 * @genpdspec: OF phandle args to use for look-up
1654 * Looks for a PM domain provider under the node specified by @genpdspec and if
1655 * found, uses xlate function of the provider to map phandle args to a PM
1658 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
1661 struct generic_pm_domain *of_genpd_get_from_provider(
1662 struct of_phandle_args *genpdspec)
1664 struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
1665 struct of_genpd_provider *provider;
1667 mutex_lock(&of_genpd_mutex);
1669 /* Check if we have such a provider in our array */
1670 list_for_each_entry(provider, &of_genpd_providers, link) {
1671 if (provider->node == genpdspec->np)
1672 genpd = provider->xlate(genpdspec, provider->data);
1677 mutex_unlock(&of_genpd_mutex);
1681 EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
1684 * genpd_dev_pm_detach - Detach a device from its PM domain.
1685 * @dev: Device to detach.
1686 * @power_off: Currently not used
1688 * Try to locate a corresponding generic PM domain, which the device was
1689 * attached to previously. If such is found, the device is detached from it.
1691 static void genpd_dev_pm_detach(struct device *dev, bool power_off)
1693 struct generic_pm_domain *pd;
1697 pd = pm_genpd_lookup_dev(dev);
1701 dev_dbg(dev, "removing from PM domain %s\n", pd->name);
1703 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1704 ret = pm_genpd_remove_device(pd, dev);
1713 dev_err(dev, "failed to remove from PM domain %s: %d",
1718 /* Check if PM domain can be powered off after removing this device. */
1719 genpd_queue_power_off_work(pd);
1722 static void genpd_dev_pm_sync(struct device *dev)
1724 struct generic_pm_domain *pd;
1726 pd = dev_to_genpd(dev);
1730 genpd_queue_power_off_work(pd);
1734 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
1735 * @dev: Device to attach.
1737 * Parse device's OF node to find a PM domain specifier. If such is found,
1738 * attaches the device to retrieved pm_domain ops.
1740 * Both generic and legacy Samsung-specific DT bindings are supported to keep
1741 * backwards compatibility with existing DTBs.
1743 * Returns 0 on successfully attached PM domain or negative error code. Note
1744 * that if a power-domain exists for the device, but it cannot be found or
1745 * turned on, then return -EPROBE_DEFER to ensure that the device is not
1746 * probed and to re-try again later.
1748 int genpd_dev_pm_attach(struct device *dev)
1750 struct of_phandle_args pd_args;
1751 struct generic_pm_domain *pd;
1761 ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
1762 "#power-domain-cells", 0, &pd_args);
1768 * Try legacy Samsung-specific bindings
1769 * (for backwards compatibility of DT ABI)
1771 pd_args.args_count = 0;
1772 pd_args.np = of_parse_phandle(dev->of_node,
1773 "samsung,power-domain", 0);
1778 pd = of_genpd_get_from_provider(&pd_args);
1780 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
1781 __func__, PTR_ERR(pd));
1782 of_node_put(dev->of_node);
1783 return -EPROBE_DEFER;
1786 dev_dbg(dev, "adding to PM domain %s\n", pd->name);
1788 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1789 ret = pm_genpd_add_device(pd, dev);
1798 dev_err(dev, "failed to add to PM domain %s: %d",
1800 of_node_put(dev->of_node);
1804 dev->pm_domain->detach = genpd_dev_pm_detach;
1805 dev->pm_domain->sync = genpd_dev_pm_sync;
1806 ret = genpd_poweron(pd);
1809 return ret ? -EPROBE_DEFER : 0;
1811 EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
1812 #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
1815 /*** debugfs support ***/
1817 #ifdef CONFIG_PM_ADVANCED_DEBUG
1818 #include <linux/pm.h>
1819 #include <linux/device.h>
1820 #include <linux/debugfs.h>
1821 #include <linux/seq_file.h>
1822 #include <linux/init.h>
1823 #include <linux/kobject.h>
1824 static struct dentry *pm_genpd_debugfs_dir;
1827 * TODO: This function is a slightly modified version of rtpm_status_show
1828 * from sysfs.c, so generalize it.
1830 static void rtpm_status_str(struct seq_file *s, struct device *dev)
1832 static const char * const status_lookup[] = {
1833 [RPM_ACTIVE] = "active",
1834 [RPM_RESUMING] = "resuming",
1835 [RPM_SUSPENDED] = "suspended",
1836 [RPM_SUSPENDING] = "suspending"
1840 if (dev->power.runtime_error)
1842 else if (dev->power.disable_depth)
1844 else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
1845 p = status_lookup[dev->power.runtime_status];
1852 static int pm_genpd_summary_one(struct seq_file *s,
1853 struct generic_pm_domain *genpd)
1855 static const char * const status_lookup[] = {
1856 [GPD_STATE_ACTIVE] = "on",
1857 [GPD_STATE_POWER_OFF] = "off"
1859 struct pm_domain_data *pm_data;
1860 const char *kobj_path;
1861 struct gpd_link *link;
1864 ret = mutex_lock_interruptible(&genpd->lock);
1866 return -ERESTARTSYS;
1868 if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
1870 seq_printf(s, "%-30s %-15s ", genpd->name, status_lookup[genpd->status]);
1873 * Modifications on the list require holding locks on both
1874 * master and slave, so we are safe.
1875 * Also genpd->name is immutable.
1877 list_for_each_entry(link, &genpd->master_links, master_node) {
1878 seq_printf(s, "%s", link->slave->name);
1879 if (!list_is_last(&link->master_node, &genpd->master_links))
1883 list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
1884 kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
1885 if (kobj_path == NULL)
1888 seq_printf(s, "\n %-50s ", kobj_path);
1889 rtpm_status_str(s, pm_data->dev);
1895 mutex_unlock(&genpd->lock);
1900 static int pm_genpd_summary_show(struct seq_file *s, void *data)
1902 struct generic_pm_domain *genpd;
1905 seq_puts(s, "domain status slaves\n");
1906 seq_puts(s, " /device runtime status\n");
1907 seq_puts(s, "----------------------------------------------------------------------\n");
1909 ret = mutex_lock_interruptible(&gpd_list_lock);
1911 return -ERESTARTSYS;
1913 list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
1914 ret = pm_genpd_summary_one(s, genpd);
1918 mutex_unlock(&gpd_list_lock);
1923 static int pm_genpd_summary_open(struct inode *inode, struct file *file)
1925 return single_open(file, pm_genpd_summary_show, NULL);
1928 static const struct file_operations pm_genpd_summary_fops = {
1929 .open = pm_genpd_summary_open,
1931 .llseek = seq_lseek,
1932 .release = single_release,
1935 static int __init pm_genpd_debug_init(void)
1939 pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
1941 if (!pm_genpd_debugfs_dir)
1944 d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
1945 pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
1951 late_initcall(pm_genpd_debug_init);
1953 static void __exit pm_genpd_debug_exit(void)
1955 debugfs_remove_recursive(pm_genpd_debugfs_dir);
1957 __exitcall(pm_genpd_debug_exit);
1958 #endif /* CONFIG_PM_ADVANCED_DEBUG */