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 #define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name) \
39 ktime_t __start = ktime_get(); \
40 type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev); \
41 s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start)); \
42 struct gpd_timing_data *__td = &dev_gpd_data(dev)->td; \
43 if (!__retval && __elapsed > __td->field) { \
44 __td->field = __elapsed; \
45 dev_dbg(dev, name " latency exceeded, new value %lld ns\n", \
47 genpd->max_off_time_changed = true; \
48 __td->constraint_changed = true; \
53 static LIST_HEAD(gpd_list);
54 static DEFINE_MUTEX(gpd_list_lock);
56 static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
58 struct generic_pm_domain *genpd = NULL, *gpd;
60 if (IS_ERR_OR_NULL(domain_name))
63 mutex_lock(&gpd_list_lock);
64 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
65 if (!strcmp(gpd->name, domain_name)) {
70 mutex_unlock(&gpd_list_lock);
75 * Get the generic PM domain for a particular struct device.
76 * This validates the struct device pointer, the PM domain pointer,
77 * and checks that the PM domain pointer is a real generic PM domain.
78 * Any failure results in NULL being returned.
80 struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
82 struct generic_pm_domain *genpd = NULL, *gpd;
84 if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
87 mutex_lock(&gpd_list_lock);
88 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
89 if (&gpd->domain == dev->pm_domain) {
94 mutex_unlock(&gpd_list_lock);
100 * This should only be used where we are certain that the pm_domain
101 * attached to the device is a genpd domain.
103 static struct generic_pm_domain *dev_to_genpd(struct device *dev)
105 if (IS_ERR_OR_NULL(dev->pm_domain))
106 return ERR_PTR(-EINVAL);
108 return pd_to_genpd(dev->pm_domain);
111 static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
113 return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
114 stop_latency_ns, "stop");
117 static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev,
121 return GENPD_DEV_CALLBACK(genpd, int, start, dev);
123 return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
124 start_latency_ns, "start");
127 static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
131 if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
132 ret = !!atomic_dec_and_test(&genpd->sd_count);
137 static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
139 atomic_inc(&genpd->sd_count);
140 smp_mb__after_atomic();
143 static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
147 if (!genpd->cpuidle_data)
150 usecs64 = genpd->power_on_latency_ns;
151 do_div(usecs64, NSEC_PER_USEC);
152 usecs64 += genpd->cpuidle_data->saved_exit_latency;
153 genpd->cpuidle_data->idle_state->exit_latency = usecs64;
156 static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
162 if (!genpd->power_on)
166 return genpd->power_on(genpd);
168 time_start = ktime_get();
169 ret = genpd->power_on(genpd);
173 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
174 if (elapsed_ns <= genpd->power_on_latency_ns)
177 genpd->power_on_latency_ns = elapsed_ns;
178 genpd->max_off_time_changed = true;
179 genpd_recalc_cpu_exit_latency(genpd);
180 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
181 genpd->name, "on", elapsed_ns);
186 static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
192 if (!genpd->power_off)
196 return genpd->power_off(genpd);
198 time_start = ktime_get();
199 ret = genpd->power_off(genpd);
203 elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
204 if (elapsed_ns <= genpd->power_off_latency_ns)
207 genpd->power_off_latency_ns = elapsed_ns;
208 genpd->max_off_time_changed = true;
209 pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
210 genpd->name, "off", elapsed_ns);
216 * __pm_genpd_poweron - Restore power to a given PM domain and its masters.
217 * @genpd: PM domain to power up.
219 * Restore power to @genpd and all of its masters so that it is possible to
220 * resume a device belonging to it.
222 static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
224 struct gpd_link *link;
227 if (genpd->status == GPD_STATE_ACTIVE
228 || (genpd->prepared_count > 0 && genpd->suspend_power_off))
231 if (genpd->cpuidle_data) {
232 cpuidle_pause_and_lock();
233 genpd->cpuidle_data->idle_state->disabled = true;
234 cpuidle_resume_and_unlock();
239 * The list is guaranteed not to change while the loop below is being
240 * executed, unless one of the masters' .power_on() callbacks fiddles
243 list_for_each_entry(link, &genpd->slave_links, slave_node) {
244 genpd_sd_counter_inc(link->master);
246 ret = pm_genpd_poweron(link->master);
248 genpd_sd_counter_dec(link->master);
253 ret = genpd_power_on(genpd, true);
258 genpd->status = GPD_STATE_ACTIVE;
262 list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
263 genpd_sd_counter_dec(link->master);
269 * pm_genpd_poweron - Restore power to a given PM domain and its masters.
270 * @genpd: PM domain to power up.
272 int pm_genpd_poweron(struct generic_pm_domain *genpd)
276 mutex_lock(&genpd->lock);
277 ret = __pm_genpd_poweron(genpd);
278 mutex_unlock(&genpd->lock);
283 * pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
284 * @domain_name: Name of the PM domain to power up.
286 int pm_genpd_name_poweron(const char *domain_name)
288 struct generic_pm_domain *genpd;
290 genpd = pm_genpd_lookup_name(domain_name);
291 return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
294 static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
296 return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
297 save_state_latency_ns, "state save");
300 static int genpd_restore_dev(struct generic_pm_domain *genpd,
301 struct device *dev, bool timed)
304 return GENPD_DEV_CALLBACK(genpd, int, restore_state, dev);
306 return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
307 restore_state_latency_ns,
311 static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
312 unsigned long val, void *ptr)
314 struct generic_pm_domain_data *gpd_data;
317 gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
318 dev = gpd_data->base.dev;
321 struct generic_pm_domain *genpd;
322 struct pm_domain_data *pdd;
324 spin_lock_irq(&dev->power.lock);
326 pdd = dev->power.subsys_data ?
327 dev->power.subsys_data->domain_data : NULL;
328 if (pdd && pdd->dev) {
329 to_gpd_data(pdd)->td.constraint_changed = true;
330 genpd = dev_to_genpd(dev);
332 genpd = ERR_PTR(-ENODATA);
335 spin_unlock_irq(&dev->power.lock);
337 if (!IS_ERR(genpd)) {
338 mutex_lock(&genpd->lock);
339 genpd->max_off_time_changed = true;
340 mutex_unlock(&genpd->lock);
344 if (!dev || dev->power.ignore_children)
352 * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
353 * @genpd: PM domait to power off.
355 * Queue up the execution of pm_genpd_poweroff() unless it's already been done
358 static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
360 queue_work(pm_wq, &genpd->power_off_work);
364 * pm_genpd_poweroff - Remove power from a given PM domain.
365 * @genpd: PM domain to power down.
367 * If all of the @genpd's devices have been suspended and all of its subdomains
368 * have been powered down, remove power from @genpd.
370 static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
372 struct pm_domain_data *pdd;
373 struct gpd_link *link;
374 unsigned int not_suspended = 0;
377 * Do not try to power off the domain in the following situations:
378 * (1) The domain is already in the "power off" state.
379 * (2) System suspend is in progress.
381 if (genpd->status == GPD_STATE_POWER_OFF
382 || genpd->prepared_count > 0)
385 if (atomic_read(&genpd->sd_count) > 0)
388 list_for_each_entry(pdd, &genpd->dev_list, list_node) {
389 enum pm_qos_flags_status stat;
391 stat = dev_pm_qos_flags(pdd->dev,
392 PM_QOS_FLAG_NO_POWER_OFF
393 | PM_QOS_FLAG_REMOTE_WAKEUP);
394 if (stat > PM_QOS_FLAGS_NONE)
397 if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
398 || pdd->dev->power.irq_safe))
402 if (not_suspended > genpd->in_progress)
405 if (genpd->gov && genpd->gov->power_down_ok) {
406 if (!genpd->gov->power_down_ok(&genpd->domain))
410 if (genpd->cpuidle_data) {
412 * If cpuidle_data is set, cpuidle should turn the domain off
413 * when the CPU in it is idle. In that case we don't decrement
414 * the subdomain counts of the master domains, so that power is
415 * not removed from the current domain prematurely as a result
416 * of cutting off the masters' power.
418 genpd->status = GPD_STATE_POWER_OFF;
419 cpuidle_pause_and_lock();
420 genpd->cpuidle_data->idle_state->disabled = false;
421 cpuidle_resume_and_unlock();
425 if (genpd->power_off) {
428 if (atomic_read(&genpd->sd_count) > 0)
432 * If sd_count > 0 at this point, one of the subdomains hasn't
433 * managed to call pm_genpd_poweron() for the master yet after
434 * incrementing it. In that case pm_genpd_poweron() will wait
435 * for us to drop the lock, so we can call .power_off() and let
436 * the pm_genpd_poweron() restore power for us (this shouldn't
437 * happen very often).
439 ret = genpd_power_off(genpd, true);
444 genpd->status = GPD_STATE_POWER_OFF;
446 list_for_each_entry(link, &genpd->slave_links, slave_node) {
447 genpd_sd_counter_dec(link->master);
448 genpd_queue_power_off_work(link->master);
455 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
456 * @work: Work structure used for scheduling the execution of this function.
458 static void genpd_power_off_work_fn(struct work_struct *work)
460 struct generic_pm_domain *genpd;
462 genpd = container_of(work, struct generic_pm_domain, power_off_work);
464 mutex_lock(&genpd->lock);
465 pm_genpd_poweroff(genpd);
466 mutex_unlock(&genpd->lock);
470 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
471 * @dev: Device to suspend.
473 * Carry out a runtime suspend of a device under the assumption that its
474 * pm_domain field points to the domain member of an object of type
475 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
477 static int pm_genpd_runtime_suspend(struct device *dev)
479 struct generic_pm_domain *genpd;
480 bool (*stop_ok)(struct device *__dev);
483 dev_dbg(dev, "%s()\n", __func__);
485 genpd = dev_to_genpd(dev);
489 stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
490 if (stop_ok && !stop_ok(dev))
493 ret = genpd_save_dev(genpd, dev);
497 ret = genpd_stop_dev(genpd, dev);
499 genpd_restore_dev(genpd, dev, true);
504 * If power.irq_safe is set, this routine will be run with interrupts
505 * off, so it can't use mutexes.
507 if (dev->power.irq_safe)
510 mutex_lock(&genpd->lock);
511 genpd->in_progress++;
512 pm_genpd_poweroff(genpd);
513 genpd->in_progress--;
514 mutex_unlock(&genpd->lock);
520 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
521 * @dev: Device to resume.
523 * Carry out a runtime resume of a device under the assumption that its
524 * pm_domain field points to the domain member of an object of type
525 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
527 static int pm_genpd_runtime_resume(struct device *dev)
529 struct generic_pm_domain *genpd;
533 dev_dbg(dev, "%s()\n", __func__);
535 genpd = dev_to_genpd(dev);
539 /* If power.irq_safe, the PM domain is never powered off. */
540 if (dev->power.irq_safe) {
545 mutex_lock(&genpd->lock);
546 ret = __pm_genpd_poweron(genpd);
547 mutex_unlock(&genpd->lock);
553 genpd_start_dev(genpd, dev, timed);
554 genpd_restore_dev(genpd, dev, timed);
559 static bool pd_ignore_unused;
560 static int __init pd_ignore_unused_setup(char *__unused)
562 pd_ignore_unused = true;
565 __setup("pd_ignore_unused", pd_ignore_unused_setup);
568 * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
570 void pm_genpd_poweroff_unused(void)
572 struct generic_pm_domain *genpd;
574 if (pd_ignore_unused) {
575 pr_warn("genpd: Not disabling unused power domains\n");
579 mutex_lock(&gpd_list_lock);
581 list_for_each_entry(genpd, &gpd_list, gpd_list_node)
582 genpd_queue_power_off_work(genpd);
584 mutex_unlock(&gpd_list_lock);
587 static int __init genpd_poweroff_unused(void)
589 pm_genpd_poweroff_unused();
592 late_initcall(genpd_poweroff_unused);
594 #ifdef CONFIG_PM_SLEEP
597 * pm_genpd_present - Check if the given PM domain has been initialized.
598 * @genpd: PM domain to check.
600 static bool pm_genpd_present(const struct generic_pm_domain *genpd)
602 const struct generic_pm_domain *gpd;
604 if (IS_ERR_OR_NULL(genpd))
607 list_for_each_entry(gpd, &gpd_list, gpd_list_node)
614 static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
617 return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
621 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
622 * @genpd: PM domain to power off, if possible.
623 * @timed: True if latency measurements are allowed.
625 * Check if the given PM domain can be powered off (during system suspend or
626 * hibernation) and do that if so. Also, in that case propagate to its masters.
628 * This function is only called in "noirq" and "syscore" stages of system power
629 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
630 * executed sequentially, so it is guaranteed that it will never run twice in
633 static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
636 struct gpd_link *link;
638 if (genpd->status == GPD_STATE_POWER_OFF)
641 if (genpd->suspended_count != genpd->device_count
642 || atomic_read(&genpd->sd_count) > 0)
645 genpd_power_off(genpd, timed);
647 genpd->status = GPD_STATE_POWER_OFF;
649 list_for_each_entry(link, &genpd->slave_links, slave_node) {
650 genpd_sd_counter_dec(link->master);
651 pm_genpd_sync_poweroff(link->master, timed);
656 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
657 * @genpd: PM domain to power on.
658 * @timed: True if latency measurements are allowed.
660 * This function is only called in "noirq" and "syscore" stages of system power
661 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
662 * executed sequentially, so it is guaranteed that it will never run twice in
665 static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
668 struct gpd_link *link;
670 if (genpd->status == GPD_STATE_ACTIVE)
673 list_for_each_entry(link, &genpd->slave_links, slave_node) {
674 pm_genpd_sync_poweron(link->master, timed);
675 genpd_sd_counter_inc(link->master);
678 genpd_power_on(genpd, timed);
680 genpd->status = GPD_STATE_ACTIVE;
684 * resume_needed - Check whether to resume a device before system suspend.
685 * @dev: Device to check.
686 * @genpd: PM domain the device belongs to.
688 * There are two cases in which a device that can wake up the system from sleep
689 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
690 * to wake up the system and it has to remain active for this purpose while the
691 * system is in the sleep state and (2) if the device is not enabled to wake up
692 * the system from sleep states and it generally doesn't generate wakeup signals
693 * by itself (those signals are generated on its behalf by other parts of the
694 * system). In the latter case it may be necessary to reconfigure the device's
695 * wakeup settings during system suspend, because it may have been set up to
696 * signal remote wakeup from the system's working state as needed by runtime PM.
697 * Return 'true' in either of the above cases.
699 static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
703 if (!device_can_wakeup(dev))
706 active_wakeup = genpd_dev_active_wakeup(genpd, dev);
707 return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
711 * pm_genpd_prepare - Start power transition of a device in a PM domain.
712 * @dev: Device to start the transition of.
714 * Start a power transition of a device (during a system-wide power transition)
715 * under the assumption that its pm_domain field points to the domain member of
716 * an object of type struct generic_pm_domain representing a PM domain
717 * consisting of I/O devices.
719 static int pm_genpd_prepare(struct device *dev)
721 struct generic_pm_domain *genpd;
724 dev_dbg(dev, "%s()\n", __func__);
726 genpd = dev_to_genpd(dev);
731 * If a wakeup request is pending for the device, it should be woken up
732 * at this point and a system wakeup event should be reported if it's
733 * set up to wake up the system from sleep states.
735 pm_runtime_get_noresume(dev);
736 if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
737 pm_wakeup_event(dev, 0);
739 if (pm_wakeup_pending()) {
744 if (resume_needed(dev, genpd))
745 pm_runtime_resume(dev);
747 mutex_lock(&genpd->lock);
749 if (genpd->prepared_count++ == 0) {
750 genpd->suspended_count = 0;
751 genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
754 mutex_unlock(&genpd->lock);
756 if (genpd->suspend_power_off) {
757 pm_runtime_put_noidle(dev);
762 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
763 * so pm_genpd_poweron() will return immediately, but if the device
764 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
765 * to make it operational.
767 pm_runtime_resume(dev);
768 __pm_runtime_disable(dev, false);
770 ret = pm_generic_prepare(dev);
772 mutex_lock(&genpd->lock);
774 if (--genpd->prepared_count == 0)
775 genpd->suspend_power_off = false;
777 mutex_unlock(&genpd->lock);
778 pm_runtime_enable(dev);
786 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
787 * @dev: Device to suspend.
789 * Suspend a device under the assumption that its pm_domain field points to the
790 * domain member of an object of type struct generic_pm_domain representing
791 * a PM domain consisting of I/O devices.
793 static int pm_genpd_suspend(struct device *dev)
795 struct generic_pm_domain *genpd;
797 dev_dbg(dev, "%s()\n", __func__);
799 genpd = dev_to_genpd(dev);
803 return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
807 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
808 * @dev: Device to suspend.
810 * Carry out a late suspend of a device under the assumption that its
811 * pm_domain field points to the domain member of an object of type
812 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
814 static int pm_genpd_suspend_late(struct device *dev)
816 struct generic_pm_domain *genpd;
818 dev_dbg(dev, "%s()\n", __func__);
820 genpd = dev_to_genpd(dev);
824 return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
828 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
829 * @dev: Device to suspend.
831 * Stop the device and remove power from the domain if all devices in it have
834 static int pm_genpd_suspend_noirq(struct device *dev)
836 struct generic_pm_domain *genpd;
838 dev_dbg(dev, "%s()\n", __func__);
840 genpd = dev_to_genpd(dev);
844 if (genpd->suspend_power_off
845 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
848 genpd_stop_dev(genpd, dev);
851 * Since all of the "noirq" callbacks are executed sequentially, it is
852 * guaranteed that this function will never run twice in parallel for
853 * the same PM domain, so it is not necessary to use locking here.
855 genpd->suspended_count++;
856 pm_genpd_sync_poweroff(genpd, true);
862 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
863 * @dev: Device to resume.
865 * Restore power to the device's PM domain, if necessary, and start the device.
867 static int pm_genpd_resume_noirq(struct device *dev)
869 struct generic_pm_domain *genpd;
871 dev_dbg(dev, "%s()\n", __func__);
873 genpd = dev_to_genpd(dev);
877 if (genpd->suspend_power_off
878 || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
882 * Since all of the "noirq" callbacks are executed sequentially, it is
883 * guaranteed that this function will never run twice in parallel for
884 * the same PM domain, so it is not necessary to use locking here.
886 pm_genpd_sync_poweron(genpd, true);
887 genpd->suspended_count--;
889 return genpd_start_dev(genpd, dev, true);
893 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
894 * @dev: Device to resume.
896 * Carry out an early resume of a device under the assumption that its
897 * pm_domain field points to the domain member of an object of type
898 * struct generic_pm_domain representing a power domain consisting of I/O
901 static int pm_genpd_resume_early(struct device *dev)
903 struct generic_pm_domain *genpd;
905 dev_dbg(dev, "%s()\n", __func__);
907 genpd = dev_to_genpd(dev);
911 return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
915 * pm_genpd_resume - Resume of device in an I/O PM domain.
916 * @dev: Device to resume.
918 * Resume a device under the assumption that its pm_domain field points to the
919 * domain member of an object of type struct generic_pm_domain representing
920 * a power domain consisting of I/O devices.
922 static int pm_genpd_resume(struct device *dev)
924 struct generic_pm_domain *genpd;
926 dev_dbg(dev, "%s()\n", __func__);
928 genpd = dev_to_genpd(dev);
932 return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
936 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
937 * @dev: Device to freeze.
939 * Freeze a device under the assumption that its pm_domain field points to the
940 * domain member of an object of type struct generic_pm_domain representing
941 * a power domain consisting of I/O devices.
943 static int pm_genpd_freeze(struct device *dev)
945 struct generic_pm_domain *genpd;
947 dev_dbg(dev, "%s()\n", __func__);
949 genpd = dev_to_genpd(dev);
953 return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
957 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
958 * @dev: Device to freeze.
960 * Carry out a late freeze of a device under the assumption that its
961 * pm_domain field points to the domain member of an object of type
962 * struct generic_pm_domain representing a power domain consisting of I/O
965 static int pm_genpd_freeze_late(struct device *dev)
967 struct generic_pm_domain *genpd;
969 dev_dbg(dev, "%s()\n", __func__);
971 genpd = dev_to_genpd(dev);
975 return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
979 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
980 * @dev: Device to freeze.
982 * Carry out a late freeze of a device under the assumption that its
983 * pm_domain field points to the domain member of an object of type
984 * struct generic_pm_domain representing a power domain consisting of I/O
987 static int pm_genpd_freeze_noirq(struct device *dev)
989 struct generic_pm_domain *genpd;
991 dev_dbg(dev, "%s()\n", __func__);
993 genpd = dev_to_genpd(dev);
997 return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
1001 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
1002 * @dev: Device to thaw.
1004 * Start the device, unless power has been removed from the domain already
1005 * before the system transition.
1007 static int pm_genpd_thaw_noirq(struct device *dev)
1009 struct generic_pm_domain *genpd;
1011 dev_dbg(dev, "%s()\n", __func__);
1013 genpd = dev_to_genpd(dev);
1017 return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev, true);
1021 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
1022 * @dev: Device to thaw.
1024 * Carry out an early thaw of a device under the assumption that its
1025 * pm_domain field points to the domain member of an object of type
1026 * struct generic_pm_domain representing a power domain consisting of I/O
1029 static int pm_genpd_thaw_early(struct device *dev)
1031 struct generic_pm_domain *genpd;
1033 dev_dbg(dev, "%s()\n", __func__);
1035 genpd = dev_to_genpd(dev);
1039 return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
1043 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
1044 * @dev: Device to thaw.
1046 * Thaw a device under the assumption that its pm_domain field points to the
1047 * domain member of an object of type struct generic_pm_domain representing
1048 * a power domain consisting of I/O devices.
1050 static int pm_genpd_thaw(struct device *dev)
1052 struct generic_pm_domain *genpd;
1054 dev_dbg(dev, "%s()\n", __func__);
1056 genpd = dev_to_genpd(dev);
1060 return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
1064 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1065 * @dev: Device to resume.
1067 * Make sure the domain will be in the same power state as before the
1068 * hibernation the system is resuming from and start the device if necessary.
1070 static int pm_genpd_restore_noirq(struct device *dev)
1072 struct generic_pm_domain *genpd;
1074 dev_dbg(dev, "%s()\n", __func__);
1076 genpd = dev_to_genpd(dev);
1081 * Since all of the "noirq" callbacks are executed sequentially, it is
1082 * guaranteed that this function will never run twice in parallel for
1083 * the same PM domain, so it is not necessary to use locking here.
1085 * At this point suspended_count == 0 means we are being run for the
1086 * first time for the given domain in the present cycle.
1088 if (genpd->suspended_count++ == 0) {
1090 * The boot kernel might put the domain into arbitrary state,
1091 * so make it appear as powered off to pm_genpd_sync_poweron(),
1092 * so that it tries to power it on in case it was really off.
1094 genpd->status = GPD_STATE_POWER_OFF;
1095 if (genpd->suspend_power_off) {
1097 * If the domain was off before the hibernation, make
1098 * sure it will be off going forward.
1100 genpd_power_off(genpd, true);
1106 if (genpd->suspend_power_off)
1109 pm_genpd_sync_poweron(genpd, true);
1111 return genpd_start_dev(genpd, dev, true);
1115 * pm_genpd_complete - Complete power transition of a device in a power domain.
1116 * @dev: Device to complete the transition of.
1118 * Complete a power transition of a device (during a system-wide power
1119 * transition) under the assumption that its pm_domain field points to the
1120 * domain member of an object of type struct generic_pm_domain representing
1121 * a power domain consisting of I/O devices.
1123 static void pm_genpd_complete(struct device *dev)
1125 struct generic_pm_domain *genpd;
1128 dev_dbg(dev, "%s()\n", __func__);
1130 genpd = dev_to_genpd(dev);
1134 mutex_lock(&genpd->lock);
1136 run_complete = !genpd->suspend_power_off;
1137 if (--genpd->prepared_count == 0)
1138 genpd->suspend_power_off = false;
1140 mutex_unlock(&genpd->lock);
1143 pm_generic_complete(dev);
1144 pm_runtime_set_active(dev);
1145 pm_runtime_enable(dev);
1146 pm_request_idle(dev);
1151 * genpd_syscore_switch - Switch power during system core suspend or resume.
1152 * @dev: Device that normally is marked as "always on" to switch power for.
1154 * This routine may only be called during the system core (syscore) suspend or
1155 * resume phase for devices whose "always on" flags are set.
1157 static void genpd_syscore_switch(struct device *dev, bool suspend)
1159 struct generic_pm_domain *genpd;
1161 genpd = dev_to_genpd(dev);
1162 if (!pm_genpd_present(genpd))
1166 genpd->suspended_count++;
1167 pm_genpd_sync_poweroff(genpd, false);
1169 pm_genpd_sync_poweron(genpd, false);
1170 genpd->suspended_count--;
1174 void pm_genpd_syscore_poweroff(struct device *dev)
1176 genpd_syscore_switch(dev, true);
1178 EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);
1180 void pm_genpd_syscore_poweron(struct device *dev)
1182 genpd_syscore_switch(dev, false);
1184 EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1186 #else /* !CONFIG_PM_SLEEP */
1188 #define pm_genpd_prepare NULL
1189 #define pm_genpd_suspend NULL
1190 #define pm_genpd_suspend_late NULL
1191 #define pm_genpd_suspend_noirq NULL
1192 #define pm_genpd_resume_early NULL
1193 #define pm_genpd_resume_noirq NULL
1194 #define pm_genpd_resume NULL
1195 #define pm_genpd_freeze NULL
1196 #define pm_genpd_freeze_late NULL
1197 #define pm_genpd_freeze_noirq NULL
1198 #define pm_genpd_thaw_early NULL
1199 #define pm_genpd_thaw_noirq NULL
1200 #define pm_genpd_thaw NULL
1201 #define pm_genpd_restore_noirq NULL
1202 #define pm_genpd_complete NULL
1204 #endif /* CONFIG_PM_SLEEP */
1206 static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
1207 struct generic_pm_domain *genpd,
1208 struct gpd_timing_data *td)
1210 struct generic_pm_domain_data *gpd_data;
1213 ret = dev_pm_get_subsys_data(dev);
1215 return ERR_PTR(ret);
1217 gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1226 gpd_data->base.dev = dev;
1227 gpd_data->td.constraint_changed = true;
1228 gpd_data->td.effective_constraint_ns = -1;
1229 gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;
1231 spin_lock_irq(&dev->power.lock);
1233 if (dev->power.subsys_data->domain_data) {
1238 dev->power.subsys_data->domain_data = &gpd_data->base;
1239 dev->pm_domain = &genpd->domain;
1241 spin_unlock_irq(&dev->power.lock);
1246 spin_unlock_irq(&dev->power.lock);
1249 dev_pm_put_subsys_data(dev);
1250 return ERR_PTR(ret);
1253 static void genpd_free_dev_data(struct device *dev,
1254 struct generic_pm_domain_data *gpd_data)
1256 spin_lock_irq(&dev->power.lock);
1258 dev->pm_domain = NULL;
1259 dev->power.subsys_data->domain_data = NULL;
1261 spin_unlock_irq(&dev->power.lock);
1264 dev_pm_put_subsys_data(dev);
1268 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1269 * @genpd: PM domain to add the device to.
1270 * @dev: Device to be added.
1271 * @td: Set of PM QoS timing parameters to attach to the device.
1273 int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
1274 struct gpd_timing_data *td)
1276 struct generic_pm_domain_data *gpd_data;
1279 dev_dbg(dev, "%s()\n", __func__);
1281 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
1284 gpd_data = genpd_alloc_dev_data(dev, genpd, td);
1285 if (IS_ERR(gpd_data))
1286 return PTR_ERR(gpd_data);
1288 mutex_lock(&genpd->lock);
1290 if (genpd->prepared_count > 0) {
1295 ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
1299 genpd->device_count++;
1300 genpd->max_off_time_changed = true;
1302 list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1305 mutex_unlock(&genpd->lock);
1308 genpd_free_dev_data(dev, gpd_data);
1310 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1316 * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
1317 * @domain_name: Name of the PM domain to add the device to.
1318 * @dev: Device to be added.
1319 * @td: Set of PM QoS timing parameters to attach to the device.
1321 int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
1322 struct gpd_timing_data *td)
1324 return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
1328 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
1329 * @genpd: PM domain to remove the device from.
1330 * @dev: Device to be removed.
1332 int pm_genpd_remove_device(struct generic_pm_domain *genpd,
1335 struct generic_pm_domain_data *gpd_data;
1336 struct pm_domain_data *pdd;
1339 dev_dbg(dev, "%s()\n", __func__);
1341 if (!genpd || genpd != pm_genpd_lookup_dev(dev))
1344 /* The above validation also means we have existing domain_data. */
1345 pdd = dev->power.subsys_data->domain_data;
1346 gpd_data = to_gpd_data(pdd);
1347 dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
1349 mutex_lock(&genpd->lock);
1351 if (genpd->prepared_count > 0) {
1356 genpd->device_count--;
1357 genpd->max_off_time_changed = true;
1359 if (genpd->detach_dev)
1360 genpd->detach_dev(genpd, dev);
1362 list_del_init(&pdd->list_node);
1364 mutex_unlock(&genpd->lock);
1366 genpd_free_dev_data(dev, gpd_data);
1371 mutex_unlock(&genpd->lock);
1372 dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1378 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
1379 * @genpd: Master PM domain to add the subdomain to.
1380 * @subdomain: Subdomain to be added.
1382 int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1383 struct generic_pm_domain *subdomain)
1385 struct gpd_link *link;
1388 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
1389 || genpd == subdomain)
1392 mutex_lock(&genpd->lock);
1393 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1395 if (genpd->status == GPD_STATE_POWER_OFF
1396 && subdomain->status != GPD_STATE_POWER_OFF) {
1401 list_for_each_entry(link, &genpd->master_links, master_node) {
1402 if (link->slave == subdomain && link->master == genpd) {
1408 link = kzalloc(sizeof(*link), GFP_KERNEL);
1413 link->master = genpd;
1414 list_add_tail(&link->master_node, &genpd->master_links);
1415 link->slave = subdomain;
1416 list_add_tail(&link->slave_node, &subdomain->slave_links);
1417 if (subdomain->status != GPD_STATE_POWER_OFF)
1418 genpd_sd_counter_inc(genpd);
1421 mutex_unlock(&subdomain->lock);
1422 mutex_unlock(&genpd->lock);
1428 * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
1429 * @master_name: Name of the master PM domain to add the subdomain to.
1430 * @subdomain_name: Name of the subdomain to be added.
1432 int pm_genpd_add_subdomain_names(const char *master_name,
1433 const char *subdomain_name)
1435 struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;
1437 if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
1440 mutex_lock(&gpd_list_lock);
1441 list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
1442 if (!master && !strcmp(gpd->name, master_name))
1445 if (!subdomain && !strcmp(gpd->name, subdomain_name))
1448 if (master && subdomain)
1451 mutex_unlock(&gpd_list_lock);
1453 return pm_genpd_add_subdomain(master, subdomain);
1457 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
1458 * @genpd: Master PM domain to remove the subdomain from.
1459 * @subdomain: Subdomain to be removed.
1461 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1462 struct generic_pm_domain *subdomain)
1464 struct gpd_link *link;
1467 if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1470 mutex_lock(&genpd->lock);
1472 list_for_each_entry(link, &genpd->master_links, master_node) {
1473 if (link->slave != subdomain)
1476 mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1478 list_del(&link->master_node);
1479 list_del(&link->slave_node);
1481 if (subdomain->status != GPD_STATE_POWER_OFF)
1482 genpd_sd_counter_dec(genpd);
1484 mutex_unlock(&subdomain->lock);
1490 mutex_unlock(&genpd->lock);
1496 * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
1497 * @genpd: PM domain to be connected with cpuidle.
1498 * @state: cpuidle state this domain can disable/enable.
1500 * Make a PM domain behave as though it contained a CPU core, that is, instead
1501 * of calling its power down routine it will enable the given cpuidle state so
1502 * that the cpuidle subsystem can power it down (if possible and desirable).
1504 int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
1506 struct cpuidle_driver *cpuidle_drv;
1507 struct gpd_cpuidle_data *cpuidle_data;
1508 struct cpuidle_state *idle_state;
1511 if (IS_ERR_OR_NULL(genpd) || state < 0)
1514 mutex_lock(&genpd->lock);
1516 if (genpd->cpuidle_data) {
1520 cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
1521 if (!cpuidle_data) {
1525 cpuidle_drv = cpuidle_driver_ref();
1530 if (cpuidle_drv->state_count <= state) {
1534 idle_state = &cpuidle_drv->states[state];
1535 if (!idle_state->disabled) {
1539 cpuidle_data->idle_state = idle_state;
1540 cpuidle_data->saved_exit_latency = idle_state->exit_latency;
1541 genpd->cpuidle_data = cpuidle_data;
1542 genpd_recalc_cpu_exit_latency(genpd);
1545 mutex_unlock(&genpd->lock);
1549 cpuidle_driver_unref();
1552 kfree(cpuidle_data);
1557 * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
1558 * @name: Name of the domain to connect to cpuidle.
1559 * @state: cpuidle state this domain can manipulate.
1561 int pm_genpd_name_attach_cpuidle(const char *name, int state)
1563 return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
1567 * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
1568 * @genpd: PM domain to remove the cpuidle connection from.
1570 * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
1573 int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
1575 struct gpd_cpuidle_data *cpuidle_data;
1576 struct cpuidle_state *idle_state;
1579 if (IS_ERR_OR_NULL(genpd))
1582 mutex_lock(&genpd->lock);
1584 cpuidle_data = genpd->cpuidle_data;
1585 if (!cpuidle_data) {
1589 idle_state = cpuidle_data->idle_state;
1590 if (!idle_state->disabled) {
1594 idle_state->exit_latency = cpuidle_data->saved_exit_latency;
1595 cpuidle_driver_unref();
1596 genpd->cpuidle_data = NULL;
1597 kfree(cpuidle_data);
1600 mutex_unlock(&genpd->lock);
1605 * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
1606 * @name: Name of the domain to disconnect cpuidle from.
1608 int pm_genpd_name_detach_cpuidle(const char *name)
1610 return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
1613 /* Default device callbacks for generic PM domains. */
1616 * pm_genpd_default_save_state - Default "save device state" for PM domains.
1617 * @dev: Device to handle.
1619 static int pm_genpd_default_save_state(struct device *dev)
1621 int (*cb)(struct device *__dev);
1623 if (dev->type && dev->type->pm)
1624 cb = dev->type->pm->runtime_suspend;
1625 else if (dev->class && dev->class->pm)
1626 cb = dev->class->pm->runtime_suspend;
1627 else if (dev->bus && dev->bus->pm)
1628 cb = dev->bus->pm->runtime_suspend;
1632 if (!cb && dev->driver && dev->driver->pm)
1633 cb = dev->driver->pm->runtime_suspend;
1635 return cb ? cb(dev) : 0;
1639 * pm_genpd_default_restore_state - Default PM domains "restore device state".
1640 * @dev: Device to handle.
1642 static int pm_genpd_default_restore_state(struct device *dev)
1644 int (*cb)(struct device *__dev);
1646 if (dev->type && dev->type->pm)
1647 cb = dev->type->pm->runtime_resume;
1648 else if (dev->class && dev->class->pm)
1649 cb = dev->class->pm->runtime_resume;
1650 else if (dev->bus && dev->bus->pm)
1651 cb = dev->bus->pm->runtime_resume;
1655 if (!cb && dev->driver && dev->driver->pm)
1656 cb = dev->driver->pm->runtime_resume;
1658 return cb ? cb(dev) : 0;
1662 * pm_genpd_init - Initialize a generic I/O PM domain object.
1663 * @genpd: PM domain object to initialize.
1664 * @gov: PM domain governor to associate with the domain (may be NULL).
1665 * @is_off: Initial value of the domain's power_is_off field.
1667 void pm_genpd_init(struct generic_pm_domain *genpd,
1668 struct dev_power_governor *gov, bool is_off)
1670 if (IS_ERR_OR_NULL(genpd))
1673 INIT_LIST_HEAD(&genpd->master_links);
1674 INIT_LIST_HEAD(&genpd->slave_links);
1675 INIT_LIST_HEAD(&genpd->dev_list);
1676 mutex_init(&genpd->lock);
1678 INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
1679 genpd->in_progress = 0;
1680 atomic_set(&genpd->sd_count, 0);
1681 genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
1682 genpd->device_count = 0;
1683 genpd->max_off_time_ns = -1;
1684 genpd->max_off_time_changed = true;
1685 genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
1686 genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
1687 genpd->domain.ops.prepare = pm_genpd_prepare;
1688 genpd->domain.ops.suspend = pm_genpd_suspend;
1689 genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
1690 genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
1691 genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
1692 genpd->domain.ops.resume_early = pm_genpd_resume_early;
1693 genpd->domain.ops.resume = pm_genpd_resume;
1694 genpd->domain.ops.freeze = pm_genpd_freeze;
1695 genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
1696 genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
1697 genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
1698 genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
1699 genpd->domain.ops.thaw = pm_genpd_thaw;
1700 genpd->domain.ops.poweroff = pm_genpd_suspend;
1701 genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
1702 genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
1703 genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
1704 genpd->domain.ops.restore_early = pm_genpd_resume_early;
1705 genpd->domain.ops.restore = pm_genpd_resume;
1706 genpd->domain.ops.complete = pm_genpd_complete;
1707 genpd->dev_ops.save_state = pm_genpd_default_save_state;
1708 genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
1710 if (genpd->flags & GENPD_FLAG_PM_CLK) {
1711 genpd->dev_ops.stop = pm_clk_suspend;
1712 genpd->dev_ops.start = pm_clk_resume;
1715 mutex_lock(&gpd_list_lock);
1716 list_add(&genpd->gpd_list_node, &gpd_list);
1717 mutex_unlock(&gpd_list_lock);
1719 EXPORT_SYMBOL_GPL(pm_genpd_init);
1721 #ifdef CONFIG_PM_GENERIC_DOMAINS_OF
1723 * Device Tree based PM domain providers.
1725 * The code below implements generic device tree based PM domain providers that
1726 * bind device tree nodes with generic PM domains registered in the system.
1728 * Any driver that registers generic PM domains and needs to support binding of
1729 * devices to these domains is supposed to register a PM domain provider, which
1730 * maps a PM domain specifier retrieved from the device tree to a PM domain.
1732 * Two simple mapping functions have been provided for convenience:
1733 * - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
1734 * - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
1739 * struct of_genpd_provider - PM domain provider registration structure
1740 * @link: Entry in global list of PM domain providers
1741 * @node: Pointer to device tree node of PM domain provider
1742 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
1744 * @data: context pointer to be passed into @xlate callback
1746 struct of_genpd_provider {
1747 struct list_head link;
1748 struct device_node *node;
1749 genpd_xlate_t xlate;
1753 /* List of registered PM domain providers. */
1754 static LIST_HEAD(of_genpd_providers);
1755 /* Mutex to protect the list above. */
1756 static DEFINE_MUTEX(of_genpd_mutex);
1759 * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
1760 * @genpdspec: OF phandle args to map into a PM domain
1761 * @data: xlate function private data - pointer to struct generic_pm_domain
1763 * This is a generic xlate function that can be used to model PM domains that
1764 * have their own device tree nodes. The private data of xlate function needs
1765 * to be a valid pointer to struct generic_pm_domain.
1767 struct generic_pm_domain *__of_genpd_xlate_simple(
1768 struct of_phandle_args *genpdspec,
1771 if (genpdspec->args_count != 0)
1772 return ERR_PTR(-EINVAL);
1775 EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);
1778 * __of_genpd_xlate_onecell() - Xlate function using a single index.
1779 * @genpdspec: OF phandle args to map into a PM domain
1780 * @data: xlate function private data - pointer to struct genpd_onecell_data
1782 * This is a generic xlate function that can be used to model simple PM domain
1783 * controllers that have one device tree node and provide multiple PM domains.
1784 * A single cell is used as an index into an array of PM domains specified in
1785 * the genpd_onecell_data struct when registering the provider.
1787 struct generic_pm_domain *__of_genpd_xlate_onecell(
1788 struct of_phandle_args *genpdspec,
1791 struct genpd_onecell_data *genpd_data = data;
1792 unsigned int idx = genpdspec->args[0];
1794 if (genpdspec->args_count != 1)
1795 return ERR_PTR(-EINVAL);
1797 if (idx >= genpd_data->num_domains) {
1798 pr_err("%s: invalid domain index %u\n", __func__, idx);
1799 return ERR_PTR(-EINVAL);
1802 if (!genpd_data->domains[idx])
1803 return ERR_PTR(-ENOENT);
1805 return genpd_data->domains[idx];
1807 EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);
1810 * __of_genpd_add_provider() - Register a PM domain provider for a node
1811 * @np: Device node pointer associated with the PM domain provider.
1812 * @xlate: Callback for decoding PM domain from phandle arguments.
1813 * @data: Context pointer for @xlate callback.
1815 int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
1818 struct of_genpd_provider *cp;
1820 cp = kzalloc(sizeof(*cp), GFP_KERNEL);
1824 cp->node = of_node_get(np);
1828 mutex_lock(&of_genpd_mutex);
1829 list_add(&cp->link, &of_genpd_providers);
1830 mutex_unlock(&of_genpd_mutex);
1831 pr_debug("Added domain provider from %s\n", np->full_name);
1835 EXPORT_SYMBOL_GPL(__of_genpd_add_provider);
1838 * of_genpd_del_provider() - Remove a previously registered PM domain provider
1839 * @np: Device node pointer associated with the PM domain provider
1841 void of_genpd_del_provider(struct device_node *np)
1843 struct of_genpd_provider *cp;
1845 mutex_lock(&of_genpd_mutex);
1846 list_for_each_entry(cp, &of_genpd_providers, link) {
1847 if (cp->node == np) {
1848 list_del(&cp->link);
1849 of_node_put(cp->node);
1854 mutex_unlock(&of_genpd_mutex);
1856 EXPORT_SYMBOL_GPL(of_genpd_del_provider);
1859 * of_genpd_get_from_provider() - Look-up PM domain
1860 * @genpdspec: OF phandle args to use for look-up
1862 * Looks for a PM domain provider under the node specified by @genpdspec and if
1863 * found, uses xlate function of the provider to map phandle args to a PM
1866 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
1869 struct generic_pm_domain *of_genpd_get_from_provider(
1870 struct of_phandle_args *genpdspec)
1872 struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
1873 struct of_genpd_provider *provider;
1875 mutex_lock(&of_genpd_mutex);
1877 /* Check if we have such a provider in our array */
1878 list_for_each_entry(provider, &of_genpd_providers, link) {
1879 if (provider->node == genpdspec->np)
1880 genpd = provider->xlate(genpdspec, provider->data);
1885 mutex_unlock(&of_genpd_mutex);
1889 EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
1892 * genpd_dev_pm_detach - Detach a device from its PM domain.
1893 * @dev: Device to detach.
1894 * @power_off: Currently not used
1896 * Try to locate a corresponding generic PM domain, which the device was
1897 * attached to previously. If such is found, the device is detached from it.
1899 static void genpd_dev_pm_detach(struct device *dev, bool power_off)
1901 struct generic_pm_domain *pd;
1905 pd = pm_genpd_lookup_dev(dev);
1909 dev_dbg(dev, "removing from PM domain %s\n", pd->name);
1911 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1912 ret = pm_genpd_remove_device(pd, dev);
1921 dev_err(dev, "failed to remove from PM domain %s: %d",
1926 /* Check if PM domain can be powered off after removing this device. */
1927 genpd_queue_power_off_work(pd);
1930 static void genpd_dev_pm_sync(struct device *dev)
1932 struct generic_pm_domain *pd;
1934 pd = dev_to_genpd(dev);
1938 genpd_queue_power_off_work(pd);
1942 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
1943 * @dev: Device to attach.
1945 * Parse device's OF node to find a PM domain specifier. If such is found,
1946 * attaches the device to retrieved pm_domain ops.
1948 * Both generic and legacy Samsung-specific DT bindings are supported to keep
1949 * backwards compatibility with existing DTBs.
1951 * Returns 0 on successfully attached PM domain or negative error code. Note
1952 * that if a power-domain exists for the device, but it cannot be found or
1953 * turned on, then return -EPROBE_DEFER to ensure that the device is not
1954 * probed and to re-try again later.
1956 int genpd_dev_pm_attach(struct device *dev)
1958 struct of_phandle_args pd_args;
1959 struct generic_pm_domain *pd;
1969 ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
1970 "#power-domain-cells", 0, &pd_args);
1976 * Try legacy Samsung-specific bindings
1977 * (for backwards compatibility of DT ABI)
1979 pd_args.args_count = 0;
1980 pd_args.np = of_parse_phandle(dev->of_node,
1981 "samsung,power-domain", 0);
1986 pd = of_genpd_get_from_provider(&pd_args);
1988 dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
1989 __func__, PTR_ERR(pd));
1990 of_node_put(dev->of_node);
1991 return -EPROBE_DEFER;
1994 dev_dbg(dev, "adding to PM domain %s\n", pd->name);
1996 for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
1997 ret = pm_genpd_add_device(pd, dev);
2006 dev_err(dev, "failed to add to PM domain %s: %d",
2008 of_node_put(dev->of_node);
2012 dev->pm_domain->detach = genpd_dev_pm_detach;
2013 dev->pm_domain->sync = genpd_dev_pm_sync;
2014 ret = pm_genpd_poweron(pd);
2017 return ret ? -EPROBE_DEFER : 0;
2019 EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
2020 #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
2023 /*** debugfs support ***/
2025 #ifdef CONFIG_PM_ADVANCED_DEBUG
2026 #include <linux/pm.h>
2027 #include <linux/device.h>
2028 #include <linux/debugfs.h>
2029 #include <linux/seq_file.h>
2030 #include <linux/init.h>
2031 #include <linux/kobject.h>
2032 static struct dentry *pm_genpd_debugfs_dir;
2035 * TODO: This function is a slightly modified version of rtpm_status_show
2036 * from sysfs.c, so generalize it.
2038 static void rtpm_status_str(struct seq_file *s, struct device *dev)
2040 static const char * const status_lookup[] = {
2041 [RPM_ACTIVE] = "active",
2042 [RPM_RESUMING] = "resuming",
2043 [RPM_SUSPENDED] = "suspended",
2044 [RPM_SUSPENDING] = "suspending"
2048 if (dev->power.runtime_error)
2050 else if (dev->power.disable_depth)
2052 else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
2053 p = status_lookup[dev->power.runtime_status];
2060 static int pm_genpd_summary_one(struct seq_file *s,
2061 struct generic_pm_domain *genpd)
2063 static const char * const status_lookup[] = {
2064 [GPD_STATE_ACTIVE] = "on",
2065 [GPD_STATE_POWER_OFF] = "off"
2067 struct pm_domain_data *pm_data;
2068 const char *kobj_path;
2069 struct gpd_link *link;
2072 ret = mutex_lock_interruptible(&genpd->lock);
2074 return -ERESTARTSYS;
2076 if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
2078 seq_printf(s, "%-30s %-15s ", genpd->name, status_lookup[genpd->status]);
2081 * Modifications on the list require holding locks on both
2082 * master and slave, so we are safe.
2083 * Also genpd->name is immutable.
2085 list_for_each_entry(link, &genpd->master_links, master_node) {
2086 seq_printf(s, "%s", link->slave->name);
2087 if (!list_is_last(&link->master_node, &genpd->master_links))
2091 list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
2092 kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
2093 if (kobj_path == NULL)
2096 seq_printf(s, "\n %-50s ", kobj_path);
2097 rtpm_status_str(s, pm_data->dev);
2103 mutex_unlock(&genpd->lock);
2108 static int pm_genpd_summary_show(struct seq_file *s, void *data)
2110 struct generic_pm_domain *genpd;
2113 seq_puts(s, "domain status slaves\n");
2114 seq_puts(s, " /device runtime status\n");
2115 seq_puts(s, "----------------------------------------------------------------------\n");
2117 ret = mutex_lock_interruptible(&gpd_list_lock);
2119 return -ERESTARTSYS;
2121 list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
2122 ret = pm_genpd_summary_one(s, genpd);
2126 mutex_unlock(&gpd_list_lock);
2131 static int pm_genpd_summary_open(struct inode *inode, struct file *file)
2133 return single_open(file, pm_genpd_summary_show, NULL);
2136 static const struct file_operations pm_genpd_summary_fops = {
2137 .open = pm_genpd_summary_open,
2139 .llseek = seq_lseek,
2140 .release = single_release,
2143 static int __init pm_genpd_debug_init(void)
2147 pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
2149 if (!pm_genpd_debugfs_dir)
2152 d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
2153 pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
2159 late_initcall(pm_genpd_debug_init);
2161 static void __exit pm_genpd_debug_exit(void)
2163 debugfs_remove_recursive(pm_genpd_debugfs_dir);
2165 __exitcall(pm_genpd_debug_exit);
2166 #endif /* CONFIG_PM_ADVANCED_DEBUG */