domain.c 61.1 KB
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/*
 * drivers/base/power/domain.c - Common code related to device power domains.
 *
 * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp.
 *
 * This file is released under the GPLv2.
 */

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#include <linux/delay.h>
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#include <linux/kernel.h>
#include <linux/io.h>
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#include <linux/platform_device.h>
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#include <linux/pm_runtime.h>
#include <linux/pm_domain.h>
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#include <linux/pm_qos.h>
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#include <linux/pm_clock.h>
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#include <linux/slab.h>
#include <linux/err.h>
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#include <linux/sched.h>
#include <linux/suspend.h>
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#include <linux/export.h>

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#define GENPD_RETRY_MAX_MS	250		/* Approximate */

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#define GENPD_DEV_CALLBACK(genpd, type, callback, dev)		\
({								\
	type (*__routine)(struct device *__d); 			\
	type __ret = (type)0;					\
								\
	__routine = genpd->dev_ops.callback; 			\
	if (__routine) {					\
		__ret = __routine(dev); 			\
	}							\
	__ret;							\
})
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#define GENPD_DEV_TIMED_CALLBACK(genpd, type, callback, dev, field, name)	\
({										\
	ktime_t __start = ktime_get();						\
	type __retval = GENPD_DEV_CALLBACK(genpd, type, callback, dev);		\
	s64 __elapsed = ktime_to_ns(ktime_sub(ktime_get(), __start));		\
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	struct gpd_timing_data *__td = &dev_gpd_data(dev)->td;			\
	if (!__retval && __elapsed > __td->field) {				\
		__td->field = __elapsed;					\
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		dev_dbg(dev, name " latency exceeded, new value %lld ns\n",	\
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			__elapsed);						\
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		genpd->max_off_time_changed = true;				\
		__td->constraint_changed = true;				\
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	}									\
	__retval;								\
})

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static LIST_HEAD(gpd_list);
static DEFINE_MUTEX(gpd_list_lock);

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static struct generic_pm_domain *pm_genpd_lookup_name(const char *domain_name)
{
	struct generic_pm_domain *genpd = NULL, *gpd;

	if (IS_ERR_OR_NULL(domain_name))
		return NULL;

	mutex_lock(&gpd_list_lock);
	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
		if (!strcmp(gpd->name, domain_name)) {
			genpd = gpd;
			break;
		}
	}
	mutex_unlock(&gpd_list_lock);
	return genpd;
}

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/*
 * Get the generic PM domain for a particular struct device.
 * This validates the struct device pointer, the PM domain pointer,
 * and checks that the PM domain pointer is a real generic PM domain.
 * Any failure results in NULL being returned.
 */
struct generic_pm_domain *pm_genpd_lookup_dev(struct device *dev)
{
	struct generic_pm_domain *genpd = NULL, *gpd;

	if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain))
		return NULL;

	mutex_lock(&gpd_list_lock);
	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
		if (&gpd->domain == dev->pm_domain) {
			genpd = gpd;
			break;
		}
	}
	mutex_unlock(&gpd_list_lock);

	return genpd;
}

/*
 * This should only be used where we are certain that the pm_domain
 * attached to the device is a genpd domain.
 */
static struct generic_pm_domain *dev_to_genpd(struct device *dev)
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{
	if (IS_ERR_OR_NULL(dev->pm_domain))
		return ERR_PTR(-EINVAL);

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	return pd_to_genpd(dev->pm_domain);
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}
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static int genpd_stop_dev(struct generic_pm_domain *genpd, struct device *dev)
{
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	return GENPD_DEV_TIMED_CALLBACK(genpd, int, stop, dev,
					stop_latency_ns, "stop");
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}

static int genpd_start_dev(struct generic_pm_domain *genpd, struct device *dev)
{
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	return GENPD_DEV_TIMED_CALLBACK(genpd, int, start, dev,
					start_latency_ns, "start");
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}

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static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
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{
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	bool ret = false;

	if (!WARN_ON(atomic_read(&genpd->sd_count) == 0))
		ret = !!atomic_dec_and_test(&genpd->sd_count);

	return ret;
}

static void genpd_sd_counter_inc(struct generic_pm_domain *genpd)
{
	atomic_inc(&genpd->sd_count);
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	smp_mb__after_atomic();
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}

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static void genpd_acquire_lock(struct generic_pm_domain *genpd)
{
	DEFINE_WAIT(wait);

	mutex_lock(&genpd->lock);
	/*
	 * Wait for the domain to transition into either the active,
	 * or the power off state.
	 */
	for (;;) {
		prepare_to_wait(&genpd->status_wait_queue, &wait,
				TASK_UNINTERRUPTIBLE);
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		if (genpd->status == GPD_STATE_ACTIVE
		    || genpd->status == GPD_STATE_POWER_OFF)
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			break;
		mutex_unlock(&genpd->lock);

		schedule();

		mutex_lock(&genpd->lock);
	}
	finish_wait(&genpd->status_wait_queue, &wait);
}

static void genpd_release_lock(struct generic_pm_domain *genpd)
{
	mutex_unlock(&genpd->lock);
}

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static void genpd_set_active(struct generic_pm_domain *genpd)
{
	if (genpd->resume_count == 0)
		genpd->status = GPD_STATE_ACTIVE;
}

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static void genpd_recalc_cpu_exit_latency(struct generic_pm_domain *genpd)
{
	s64 usecs64;

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	if (!genpd->cpuidle_data)
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		return;

	usecs64 = genpd->power_on_latency_ns;
	do_div(usecs64, NSEC_PER_USEC);
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	usecs64 += genpd->cpuidle_data->saved_exit_latency;
	genpd->cpuidle_data->idle_state->exit_latency = usecs64;
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}

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static int genpd_power_on(struct generic_pm_domain *genpd, bool timed)
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{
	ktime_t time_start;
	s64 elapsed_ns;
	int ret;

	if (!genpd->power_on)
		return 0;

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	if (!timed)
		return genpd->power_on(genpd);

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	time_start = ktime_get();
	ret = genpd->power_on(genpd);
	if (ret)
		return ret;

	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
	if (elapsed_ns <= genpd->power_on_latency_ns)
		return ret;

	genpd->power_on_latency_ns = elapsed_ns;
	genpd->max_off_time_changed = true;
	genpd_recalc_cpu_exit_latency(genpd);
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	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
		 genpd->name, "on", elapsed_ns);
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	return ret;
}

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static int genpd_power_off(struct generic_pm_domain *genpd, bool timed)
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{
	ktime_t time_start;
	s64 elapsed_ns;
	int ret;

	if (!genpd->power_off)
		return 0;

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	if (!timed)
		return genpd->power_off(genpd);

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	time_start = ktime_get();
	ret = genpd->power_off(genpd);
	if (ret == -EBUSY)
		return ret;

	elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
	if (elapsed_ns <= genpd->power_off_latency_ns)
		return ret;

	genpd->power_off_latency_ns = elapsed_ns;
	genpd->max_off_time_changed = true;
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	pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
		 genpd->name, "off", elapsed_ns);
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	return ret;
}

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/**
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 * __pm_genpd_poweron - Restore power to a given PM domain and its masters.
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 * @genpd: PM domain to power up.
 *
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 * Restore power to @genpd and all of its masters so that it is possible to
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 * resume a device belonging to it.
 */
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static int __pm_genpd_poweron(struct generic_pm_domain *genpd)
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	__releases(&genpd->lock) __acquires(&genpd->lock)
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{
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	struct gpd_link *link;
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	DEFINE_WAIT(wait);
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	int ret = 0;

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	/* If the domain's master is being waited for, we have to wait too. */
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	for (;;) {
		prepare_to_wait(&genpd->status_wait_queue, &wait,
				TASK_UNINTERRUPTIBLE);
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		if (genpd->status != GPD_STATE_WAIT_MASTER)
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			break;
		mutex_unlock(&genpd->lock);
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		schedule();

		mutex_lock(&genpd->lock);
	}
	finish_wait(&genpd->status_wait_queue, &wait);
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	if (genpd->status == GPD_STATE_ACTIVE
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	    || (genpd->prepared_count > 0 && genpd->suspend_power_off))
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		return 0;
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	if (genpd->status != GPD_STATE_POWER_OFF) {
		genpd_set_active(genpd);
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		return 0;
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	}

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	if (genpd->cpuidle_data) {
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		cpuidle_pause_and_lock();
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		genpd->cpuidle_data->idle_state->disabled = true;
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		cpuidle_resume_and_unlock();
		goto out;
	}

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	/*
	 * The list is guaranteed not to change while the loop below is being
	 * executed, unless one of the masters' .power_on() callbacks fiddles
	 * with it.
	 */
	list_for_each_entry(link, &genpd->slave_links, slave_node) {
		genpd_sd_counter_inc(link->master);
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		genpd->status = GPD_STATE_WAIT_MASTER;
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		mutex_unlock(&genpd->lock);

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		ret = pm_genpd_poweron(link->master);
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		mutex_lock(&genpd->lock);

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		/*
		 * The "wait for parent" status is guaranteed not to change
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		 * while the master is powering on.
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		 */
		genpd->status = GPD_STATE_POWER_OFF;
		wake_up_all(&genpd->status_wait_queue);
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		if (ret) {
			genpd_sd_counter_dec(link->master);
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			goto err;
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		}
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	}

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	ret = genpd_power_on(genpd, true);
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	if (ret)
		goto err;
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 out:
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	genpd_set_active(genpd);

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	return 0;
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 err:
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	list_for_each_entry_continue_reverse(link, &genpd->slave_links, slave_node)
		genpd_sd_counter_dec(link->master);
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	return ret;
}

/**
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 * pm_genpd_poweron - Restore power to a given PM domain and its masters.
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 * @genpd: PM domain to power up.
 */
int pm_genpd_poweron(struct generic_pm_domain *genpd)
{
	int ret;

	mutex_lock(&genpd->lock);
	ret = __pm_genpd_poweron(genpd);
	mutex_unlock(&genpd->lock);
	return ret;
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}

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/**
 * pm_genpd_name_poweron - Restore power to a given PM domain and its masters.
 * @domain_name: Name of the PM domain to power up.
 */
int pm_genpd_name_poweron(const char *domain_name)
{
	struct generic_pm_domain *genpd;

	genpd = pm_genpd_lookup_name(domain_name);
	return genpd ? pm_genpd_poweron(genpd) : -EINVAL;
}

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static int genpd_start_dev_no_timing(struct generic_pm_domain *genpd,
				     struct device *dev)
{
	return GENPD_DEV_CALLBACK(genpd, int, start, dev);
}

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static int genpd_save_dev(struct generic_pm_domain *genpd, struct device *dev)
{
	return GENPD_DEV_TIMED_CALLBACK(genpd, int, save_state, dev,
					save_state_latency_ns, "state save");
}

static int genpd_restore_dev(struct generic_pm_domain *genpd, struct device *dev)
{
	return GENPD_DEV_TIMED_CALLBACK(genpd, int, restore_state, dev,
					restore_state_latency_ns,
					"state restore");
}

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static int genpd_dev_pm_qos_notifier(struct notifier_block *nb,
				     unsigned long val, void *ptr)
{
	struct generic_pm_domain_data *gpd_data;
	struct device *dev;

	gpd_data = container_of(nb, struct generic_pm_domain_data, nb);
	dev = gpd_data->base.dev;

	for (;;) {
		struct generic_pm_domain *genpd;
		struct pm_domain_data *pdd;

		spin_lock_irq(&dev->power.lock);

		pdd = dev->power.subsys_data ?
				dev->power.subsys_data->domain_data : NULL;
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		if (pdd && pdd->dev) {
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			to_gpd_data(pdd)->td.constraint_changed = true;
			genpd = dev_to_genpd(dev);
		} else {
			genpd = ERR_PTR(-ENODATA);
		}

		spin_unlock_irq(&dev->power.lock);

		if (!IS_ERR(genpd)) {
			mutex_lock(&genpd->lock);
			genpd->max_off_time_changed = true;
			mutex_unlock(&genpd->lock);
		}

		dev = dev->parent;
		if (!dev || dev->power.ignore_children)
			break;
	}

	return NOTIFY_DONE;
}

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/**
 * __pm_genpd_save_device - Save the pre-suspend state of a device.
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 * @pdd: Domain data of the device to save the state of.
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 * @genpd: PM domain the device belongs to.
 */
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static int __pm_genpd_save_device(struct pm_domain_data *pdd,
424
				  struct generic_pm_domain *genpd)
425
	__releases(&genpd->lock) __acquires(&genpd->lock)
426
{
427
	struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
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	struct device *dev = pdd->dev;
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	int ret = 0;

431
	if (gpd_data->need_restore > 0)
432 433
		return 0;

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	/*
	 * If the value of the need_restore flag is still unknown at this point,
	 * we trust that pm_genpd_poweroff() has verified that the device is
	 * already runtime PM suspended.
	 */
	if (gpd_data->need_restore < 0) {
		gpd_data->need_restore = 1;
		return 0;
	}

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	mutex_unlock(&genpd->lock);

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	genpd_start_dev(genpd, dev);
	ret = genpd_save_dev(genpd, dev);
	genpd_stop_dev(genpd, dev);
449

450 451
	mutex_lock(&genpd->lock);

452
	if (!ret)
453
		gpd_data->need_restore = 1;
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	return ret;
}

/**
 * __pm_genpd_restore_device - Restore the pre-suspend state of a device.
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 * @pdd: Domain data of the device to restore the state of.
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 * @genpd: PM domain the device belongs to.
 */
463
static void __pm_genpd_restore_device(struct pm_domain_data *pdd,
464
				      struct generic_pm_domain *genpd)
465
	__releases(&genpd->lock) __acquires(&genpd->lock)
466
{
467
	struct generic_pm_domain_data *gpd_data = to_gpd_data(pdd);
468
	struct device *dev = pdd->dev;
469
	int need_restore = gpd_data->need_restore;
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471
	gpd_data->need_restore = 0;
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	mutex_unlock(&genpd->lock);

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	genpd_start_dev(genpd, dev);
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	/*
	 * Call genpd_restore_dev() for recently added devices too (need_restore
	 * is negative then).
	 */
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	if (need_restore)
		genpd_restore_dev(genpd, dev);
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483
	mutex_lock(&genpd->lock);
484 485
}

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/**
 * genpd_abort_poweroff - Check if a PM domain power off should be aborted.
 * @genpd: PM domain to check.
 *
 * Return true if a PM domain's status changed to GPD_STATE_ACTIVE during
 * a "power off" operation, which means that a "power on" has occured in the
 * meantime, or if its resume_count field is different from zero, which means
 * that one of its devices has been resumed in the meantime.
 */
static bool genpd_abort_poweroff(struct generic_pm_domain *genpd)
{
497
	return genpd->status == GPD_STATE_WAIT_MASTER
498
		|| genpd->status == GPD_STATE_ACTIVE || genpd->resume_count > 0;
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}

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/**
 * genpd_queue_power_off_work - Queue up the execution of pm_genpd_poweroff().
 * @genpd: PM domait to power off.
 *
 * Queue up the execution of pm_genpd_poweroff() unless it's already been done
 * before.
 */
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static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
509
{
510
	queue_work(pm_wq, &genpd->power_off_work);
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}

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/**
 * pm_genpd_poweroff - Remove power from a given PM domain.
 * @genpd: PM domain to power down.
 *
 * If all of the @genpd's devices have been suspended and all of its subdomains
 * have been powered down, run the runtime suspend callbacks provided by all of
 * the @genpd's devices' drivers and remove power from @genpd.
 */
static int pm_genpd_poweroff(struct generic_pm_domain *genpd)
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	__releases(&genpd->lock) __acquires(&genpd->lock)
523
{
524
	struct pm_domain_data *pdd;
525
	struct gpd_link *link;
526
	unsigned int not_suspended;
527
	int ret = 0;
528

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 start:
	/*
	 * Do not try to power off the domain in the following situations:
	 * (1) The domain is already in the "power off" state.
533
	 * (2) The domain is waiting for its master to power up.
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	 * (3) One of the domain's devices is being resumed right now.
535
	 * (4) System suspend is in progress.
536
	 */
537
	if (genpd->status == GPD_STATE_POWER_OFF
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	    || genpd->status == GPD_STATE_WAIT_MASTER
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	    || genpd->resume_count > 0 || genpd->prepared_count > 0)
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		return 0;

542
	if (atomic_read(&genpd->sd_count) > 0)
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		return -EBUSY;

	not_suspended = 0;
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	list_for_each_entry(pdd, &genpd->dev_list, list_node) {
		enum pm_qos_flags_status stat;

		stat = dev_pm_qos_flags(pdd->dev,
					PM_QOS_FLAG_NO_POWER_OFF
						| PM_QOS_FLAG_REMOTE_WAKEUP);
		if (stat > PM_QOS_FLAGS_NONE)
			return -EBUSY;

555
		if (pdd->dev->driver && (!pm_runtime_suspended(pdd->dev)
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		    || pdd->dev->power.irq_safe))
557
			not_suspended++;
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	}
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	if (not_suspended > genpd->in_progress)
		return -EBUSY;

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	if (genpd->poweroff_task) {
		/*
		 * Another instance of pm_genpd_poweroff() is executing
		 * callbacks, so tell it to start over and return.
		 */
		genpd->status = GPD_STATE_REPEAT;
		return 0;
	}

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	if (genpd->gov && genpd->gov->power_down_ok) {
		if (!genpd->gov->power_down_ok(&genpd->domain))
			return -EAGAIN;
	}

577
	genpd->status = GPD_STATE_BUSY;
578
	genpd->poweroff_task = current;
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580
	list_for_each_entry_reverse(pdd, &genpd->dev_list, list_node) {
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		ret = atomic_read(&genpd->sd_count) == 0 ?
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			__pm_genpd_save_device(pdd, genpd) : -EBUSY;
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		if (genpd_abort_poweroff(genpd))
			goto out;

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		if (ret) {
			genpd_set_active(genpd);
			goto out;
		}
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		if (genpd->status == GPD_STATE_REPEAT) {
			genpd->poweroff_task = NULL;
			goto start;
		}
	}
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	if (genpd->cpuidle_data) {
599
		/*
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		 * If cpuidle_data is set, cpuidle should turn the domain off
		 * when the CPU in it is idle.  In that case we don't decrement
		 * the subdomain counts of the master domains, so that power is
		 * not removed from the current domain prematurely as a result
		 * of cutting off the masters' power.
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		 */
		genpd->status = GPD_STATE_POWER_OFF;
		cpuidle_pause_and_lock();
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		genpd->cpuidle_data->idle_state->disabled = false;
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		cpuidle_resume_and_unlock();
		goto out;
	}

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	if (genpd->power_off) {
		if (atomic_read(&genpd->sd_count) > 0) {
			ret = -EBUSY;
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			goto out;
		}
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619
		/*
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		 * If sd_count > 0 at this point, one of the subdomains hasn't
		 * managed to call pm_genpd_poweron() for the master yet after
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		 * incrementing it.  In that case pm_genpd_poweron() will wait
		 * for us to drop the lock, so we can call .power_off() and let
		 * the pm_genpd_poweron() restore power for us (this shouldn't
		 * happen very often).
		 */
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		ret = genpd_power_off(genpd, true);
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		if (ret == -EBUSY) {
			genpd_set_active(genpd);
			goto out;
		}
	}
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	genpd->status = GPD_STATE_POWER_OFF;
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	list_for_each_entry(link, &genpd->slave_links, slave_node) {
		genpd_sd_counter_dec(link->master);
		genpd_queue_power_off_work(link->master);
	}
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 out:
	genpd->poweroff_task = NULL;
	wake_up_all(&genpd->status_wait_queue);
	return ret;
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}

/**
 * genpd_power_off_work_fn - Power off PM domain whose subdomain count is 0.
 * @work: Work structure used for scheduling the execution of this function.
 */
static void genpd_power_off_work_fn(struct work_struct *work)
{
	struct generic_pm_domain *genpd;

	genpd = container_of(work, struct generic_pm_domain, power_off_work);

657
	genpd_acquire_lock(genpd);
658
	pm_genpd_poweroff(genpd);
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	genpd_release_lock(genpd);
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}

/**
 * pm_genpd_runtime_suspend - Suspend a device belonging to I/O PM domain.
 * @dev: Device to suspend.
 *
 * Carry out a runtime suspend of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 */
static int pm_genpd_runtime_suspend(struct device *dev)
{
	struct generic_pm_domain *genpd;
673
	struct generic_pm_domain_data *gpd_data;
674
	bool (*stop_ok)(struct device *__dev);
675
	int ret;
676 677 678

	dev_dbg(dev, "%s()\n", __func__);

679 680
	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
681 682
		return -EINVAL;

683 684 685 686
	stop_ok = genpd->gov ? genpd->gov->stop_ok : NULL;
	if (stop_ok && !stop_ok(dev))
		return -EBUSY;

687 688 689
	ret = genpd_stop_dev(genpd, dev);
	if (ret)
		return ret;
690

691 692 693 694 695 696 697
	/*
	 * If power.irq_safe is set, this routine will be run with interrupts
	 * off, so it can't use mutexes.
	 */
	if (dev->power.irq_safe)
		return 0;

698
	mutex_lock(&genpd->lock);
699 700 701 702 703 704 705 706 707 708

	/*
	 * If we have an unknown state of the need_restore flag, it means none
	 * of the runtime PM callbacks has been invoked yet. Let's update the
	 * flag to reflect that the current state is active.
	 */
	gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
	if (gpd_data->need_restore < 0)
		gpd_data->need_restore = 0;

709 710 711
	genpd->in_progress++;
	pm_genpd_poweroff(genpd);
	genpd->in_progress--;
712
	mutex_unlock(&genpd->lock);
713 714 715 716 717 718 719 720 721 722 723 724 725 726 727

	return 0;
}

/**
 * pm_genpd_runtime_resume - Resume a device belonging to I/O PM domain.
 * @dev: Device to resume.
 *
 * Carry out a runtime resume of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 */
static int pm_genpd_runtime_resume(struct device *dev)
{
	struct generic_pm_domain *genpd;
728
	DEFINE_WAIT(wait);
729 730 731 732
	int ret;

	dev_dbg(dev, "%s()\n", __func__);

733 734
	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
735 736
		return -EINVAL;

737 738
	/* If power.irq_safe, the PM domain is never powered off. */
	if (dev->power.irq_safe)
739
		return genpd_start_dev_no_timing(genpd, dev);
740

741
	mutex_lock(&genpd->lock);
742 743 744 745 746
	ret = __pm_genpd_poweron(genpd);
	if (ret) {
		mutex_unlock(&genpd->lock);
		return ret;
	}
747
	genpd->status = GPD_STATE_BUSY;
748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
	genpd->resume_count++;
	for (;;) {
		prepare_to_wait(&genpd->status_wait_queue, &wait,
				TASK_UNINTERRUPTIBLE);
		/*
		 * If current is the powering off task, we have been called
		 * reentrantly from one of the device callbacks, so we should
		 * not wait.
		 */
		if (!genpd->poweroff_task || genpd->poweroff_task == current)
			break;
		mutex_unlock(&genpd->lock);

		schedule();

		mutex_lock(&genpd->lock);
	}
	finish_wait(&genpd->status_wait_queue, &wait);
766
	__pm_genpd_restore_device(dev->power.subsys_data->domain_data, genpd);
767 768
	genpd->resume_count--;
	genpd_set_active(genpd);
769
	wake_up_all(&genpd->status_wait_queue);
770
	mutex_unlock(&genpd->lock);
771

772 773 774
	return 0;
}

775 776 777 778 779 780 781 782
static bool pd_ignore_unused;
static int __init pd_ignore_unused_setup(char *__unused)
{
	pd_ignore_unused = true;
	return 1;
}
__setup("pd_ignore_unused", pd_ignore_unused_setup);

783 784 785 786 787 788 789
/**
 * pm_genpd_poweroff_unused - Power off all PM domains with no devices in use.
 */
void pm_genpd_poweroff_unused(void)
{
	struct generic_pm_domain *genpd;

790 791 792 793 794
	if (pd_ignore_unused) {
		pr_warn("genpd: Not disabling unused power domains\n");
		return;
	}

795 796 797 798 799 800 801 802
	mutex_lock(&gpd_list_lock);

	list_for_each_entry(genpd, &gpd_list, gpd_list_node)
		genpd_queue_power_off_work(genpd);

	mutex_unlock(&gpd_list_lock);
}

803 804 805 806 807 808 809
static int __init genpd_poweroff_unused(void)
{
	pm_genpd_poweroff_unused();
	return 0;
}
late_initcall(genpd_poweroff_unused);

810 811
#ifdef CONFIG_PM_SLEEP

812 813 814 815
/**
 * pm_genpd_present - Check if the given PM domain has been initialized.
 * @genpd: PM domain to check.
 */
816
static bool pm_genpd_present(const struct generic_pm_domain *genpd)
817
{
818
	const struct generic_pm_domain *gpd;
819 820 821 822 823 824 825 826 827 828 829

	if (IS_ERR_OR_NULL(genpd))
		return false;

	list_for_each_entry(gpd, &gpd_list, gpd_list_node)
		if (gpd == genpd)
			return true;

	return false;
}

830 831 832 833 834 835
static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd,
				    struct device *dev)
{
	return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev);
}

836
/**
837
 * pm_genpd_sync_poweroff - Synchronously power off a PM domain and its masters.
838
 * @genpd: PM domain to power off, if possible.
839
 * @timed: True if latency measurements are allowed.
840 841
 *
 * Check if the given PM domain can be powered off (during system suspend or
842
 * hibernation) and do that if so.  Also, in that case propagate to its masters.
843
 *
844 845 846 847
 * This function is only called in "noirq" and "syscore" stages of system power
 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 * executed sequentially, so it is guaranteed that it will never run twice in
 * parallel).
848
 */
849 850
static void pm_genpd_sync_poweroff(struct generic_pm_domain *genpd,
				   bool timed)
851
{
852
	struct gpd_link *link;
853

854
	if (genpd->status == GPD_STATE_POWER_OFF)
855 856
		return;

857 858
	if (genpd->suspended_count != genpd->device_count
	    || atomic_read(&genpd->sd_count) > 0)
859 860
		return;

861
	genpd_power_off(genpd, timed);
862

863
	genpd->status = GPD_STATE_POWER_OFF;
864 865 866

	list_for_each_entry(link, &genpd->slave_links, slave_node) {
		genpd_sd_counter_dec(link->master);
867
		pm_genpd_sync_poweroff(link->master, timed);
868 869 870
	}
}

871 872 873
/**
 * pm_genpd_sync_poweron - Synchronously power on a PM domain and its masters.
 * @genpd: PM domain to power on.
874
 * @timed: True if latency measurements are allowed.
875
 *
876 877 878 879
 * This function is only called in "noirq" and "syscore" stages of system power
 * transitions, so it need not acquire locks (all of the "noirq" callbacks are
 * executed sequentially, so it is guaranteed that it will never run twice in
 * parallel).
880
 */
881 882
static void pm_genpd_sync_poweron(struct generic_pm_domain *genpd,
				  bool timed)
883 884 885 886 887 888 889
{
	struct gpd_link *link;

	if (genpd->status != GPD_STATE_POWER_OFF)
		return;

	list_for_each_entry(link, &genpd->slave_links, slave_node) {
890
		pm_genpd_sync_poweron(link->master, timed);
891 892 893
		genpd_sd_counter_inc(link->master);
	}

894
	genpd_power_on(genpd, timed);
895 896 897 898

	genpd->status = GPD_STATE_ACTIVE;
}

899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921
/**
 * resume_needed - Check whether to resume a device before system suspend.
 * @dev: Device to check.
 * @genpd: PM domain the device belongs to.
 *
 * There are two cases in which a device that can wake up the system from sleep
 * states should be resumed by pm_genpd_prepare(): (1) if the device is enabled
 * to wake up the system and it has to remain active for this purpose while the
 * system is in the sleep state and (2) if the device is not enabled to wake up
 * the system from sleep states and it generally doesn't generate wakeup signals
 * by itself (those signals are generated on its behalf by other parts of the
 * system).  In the latter case it may be necessary to reconfigure the device's
 * wakeup settings during system suspend, because it may have been set up to
 * signal remote wakeup from the system's working state as needed by runtime PM.
 * Return 'true' in either of the above cases.
 */
static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd)
{
	bool active_wakeup;

	if (!device_can_wakeup(dev))
		return false;

922
	active_wakeup = genpd_dev_active_wakeup(genpd, dev);
923 924 925
	return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
}

926 927 928 929 930 931 932 933 934 935 936 937
/**
 * pm_genpd_prepare - Start power transition of a device in a PM domain.
 * @dev: Device to start the transition of.
 *
 * Start a power transition of a device (during a system-wide power transition)
 * under the assumption that its pm_domain field points to the domain member of
 * an object of type struct generic_pm_domain representing a PM domain
 * consisting of I/O devices.
 */
static int pm_genpd_prepare(struct device *dev)
{
	struct generic_pm_domain *genpd;
938
	int ret;
939 940 941 942 943 944 945

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

946 947 948 949 950 951 952 953 954 955
	/*
	 * If a wakeup request is pending for the device, it should be woken up
	 * at this point and a system wakeup event should be reported if it's
	 * set up to wake up the system from sleep states.
	 */
	pm_runtime_get_noresume(dev);
	if (pm_runtime_barrier(dev) && device_may_wakeup(dev))
		pm_wakeup_event(dev, 0);

	if (pm_wakeup_pending()) {
956
		pm_runtime_put(dev);
957 958 959
		return -EBUSY;
	}

960 961 962
	if (resume_needed(dev, genpd))
		pm_runtime_resume(dev);

963
	genpd_acquire_lock(genpd);
964

965 966
	if (genpd->prepared_count++ == 0) {
		genpd->suspended_count = 0;
967
		genpd->suspend_power_off = genpd->status == GPD_STATE_POWER_OFF;
968
	}
969 970

	genpd_release_lock(genpd);
971 972

	if (genpd->suspend_power_off) {
973
		pm_runtime_put_noidle(dev);
974 975 976 977
		return 0;
	}

	/*
978 979
	 * The PM domain must be in the GPD_STATE_ACTIVE state at this point,
	 * so pm_genpd_poweron() will return immediately, but if the device
980
	 * is suspended (e.g. it's been stopped by genpd_stop_dev()), we need
981
	 * to make it operational.
982
	 */
983
	pm_runtime_resume(dev);
984 985
	__pm_runtime_disable(dev, false);

986 987 988 989 990 991 992 993
	ret = pm_generic_prepare(dev);
	if (ret) {
		mutex_lock(&genpd->lock);

		if (--genpd->prepared_count == 0)
			genpd->suspend_power_off = false;

		mutex_unlock(&genpd->lock);
994
		pm_runtime_enable(dev);
995
	}
996

997
	pm_runtime_put(dev);
998
	return ret;
999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
}

/**
 * pm_genpd_suspend - Suspend a device belonging to an I/O PM domain.
 * @dev: Device to suspend.
 *
 * Suspend a device under the assumption that its pm_domain field points to the
 * domain member of an object of type struct generic_pm_domain representing
 * a PM domain consisting of I/O devices.
 */
static int pm_genpd_suspend(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1019
	return genpd->suspend_power_off ? 0 : pm_generic_suspend(dev);
1020 1021 1022
}

/**
1023
 * pm_genpd_suspend_late - Late suspend of a device from an I/O PM domain.
1024 1025 1026 1027 1028 1029
 * @dev: Device to suspend.
 *
 * Carry out a late suspend of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a PM domain consisting of I/O devices.
 */
1030
static int pm_genpd_suspend_late(struct device *dev)
1031 1032 1033 1034 1035 1036 1037 1038 1039
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1040
	return genpd->suspend_power_off ? 0 : pm_generic_suspend_late(dev);
1041
}
1042

1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
/**
 * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain.
 * @dev: Device to suspend.
 *
 * Stop the device and remove power from the domain if all devices in it have
 * been stopped.
 */
static int pm_genpd_suspend_noirq(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;
1059

1060
	if (genpd->suspend_power_off
1061
	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1062 1063
		return 0;

1064
	genpd_stop_dev(genpd, dev);
1065 1066 1067 1068 1069 1070 1071

	/*
	 * Since all of the "noirq" callbacks are executed sequentially, it is
	 * guaranteed that this function will never run twice in parallel for
	 * the same PM domain, so it is not necessary to use locking here.
	 */
	genpd->suspended_count++;
1072
	pm_genpd_sync_poweroff(genpd, true);
1073 1074 1075 1076 1077

	return 0;
}

/**
1078
 * pm_genpd_resume_noirq - Start of resume of device in an I/O PM domain.
1079 1080
 * @dev: Device to resume.
 *
1081
 * Restore power to the device's PM domain, if necessary, and start the device.
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092
 */
static int pm_genpd_resume_noirq(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1093
	if (genpd->suspend_power_off
1094
	    || (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)))
1095 1096 1097 1098 1099 1100 1101
		return 0;

	/*
	 * Since all of the "noirq" callbacks are executed sequentially, it is
	 * guaranteed that this function will never run twice in parallel for
	 * the same PM domain, so it is not necessary to use locking here.
	 */
1102
	pm_genpd_sync_poweron(genpd, true);
1103 1104
	genpd->suspended_count--;

1105
	return genpd_start_dev(genpd, dev);
1106 1107 1108
}

/**
1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126
 * pm_genpd_resume_early - Early resume of a device in an I/O PM domain.
 * @dev: Device to resume.
 *
 * Carry out an early resume of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a power domain consisting of I/O
 * devices.
 */
static int pm_genpd_resume_early(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1127
	return genpd->suspend_power_off ? 0 : pm_generic_resume_early(dev);
1128 1129 1130 1131
}

/**
 * pm_genpd_resume - Resume of device in an I/O PM domain.
1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147
 * @dev: Device to resume.
 *
 * Resume a device under the assumption that its pm_domain field points to the
 * domain member of an object of type struct generic_pm_domain representing
 * a power domain consisting of I/O devices.
 */
static int pm_genpd_resume(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1148
	return genpd->suspend_power_off ? 0 : pm_generic_resume(dev);
1149 1150 1151
}

/**
1152
 * pm_genpd_freeze - Freezing a device in an I/O PM domain.
1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168
 * @dev: Device to freeze.
 *
 * Freeze a device under the assumption that its pm_domain field points to the
 * domain member of an object of type struct generic_pm_domain representing
 * a power domain consisting of I/O devices.
 */
static int pm_genpd_freeze(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1169
	return genpd->suspend_power_off ? 0 : pm_generic_freeze(dev);
1170 1171 1172
}

/**
1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
 * pm_genpd_freeze_late - Late freeze of a device in an I/O PM domain.
 * @dev: Device to freeze.
 *
 * Carry out a late freeze of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a power domain consisting of I/O
 * devices.
 */
static int pm_genpd_freeze_late(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1191
	return genpd->suspend_power_off ? 0 : pm_generic_freeze_late(dev);
1192 1193 1194 1195
}

/**
 * pm_genpd_freeze_noirq - Completion of freezing a device in an I/O PM domain.
1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212
 * @dev: Device to freeze.
 *
 * Carry out a late freeze of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a power domain consisting of I/O
 * devices.
 */
static int pm_genpd_freeze_noirq(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1213
	return genpd->suspend_power_off ? 0 : genpd_stop_dev(genpd, dev);
1214
}
1215

1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
/**
 * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain.
 * @dev: Device to thaw.
 *
 * Start the device, unless power has been removed from the domain already
 * before the system transition.
 */
static int pm_genpd_thaw_noirq(struct device *dev)
{
	struct generic_pm_domain *genpd;
1226

1227
	dev_dbg(dev, "%s()\n", __func__);
1228

1229 1230 1231 1232
	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1233
	return genpd->suspend_power_off ? 0 : genpd_start_dev(genpd, dev);
1234 1235 1236
}

/**
1237
 * pm_genpd_thaw_early - Early thaw of device in an I/O PM domain.
1238 1239 1240 1241 1242 1243 1244
 * @dev: Device to thaw.
 *
 * Carry out an early thaw of a device under the assumption that its
 * pm_domain field points to the domain member of an object of type
 * struct generic_pm_domain representing a power domain consisting of I/O
 * devices.
 */
1245
static int pm_genpd_thaw_early(struct device *dev)
1246 1247 1248 1249 1250 1251 1252 1253 1254
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1255
	return genpd->suspend_power_off ? 0 : pm_generic_thaw_early(dev);
1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275
}

/**
 * pm_genpd_thaw - Thaw a device belonging to an I/O power domain.
 * @dev: Device to thaw.
 *
 * Thaw a device under the assumption that its pm_domain field points to the
 * domain member of an object of type struct generic_pm_domain representing
 * a power domain consisting of I/O devices.
 */
static int pm_genpd_thaw(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

1276
	return genpd->suspend_power_off ? 0 : pm_generic_thaw(dev);
1277 1278 1279
}

/**
1280
 * pm_genpd_restore_noirq - Start of restore of device in an I/O PM domain.
1281 1282
 * @dev: Device to resume.
 *
1283 1284
 * Make sure the domain will be in the same power state as before the
 * hibernation the system is resuming from and start the device if necessary.
1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299
 */
static int pm_genpd_restore_noirq(struct device *dev)
{
	struct generic_pm_domain *genpd;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return -EINVAL;

	/*
	 * Since all of the "noirq" callbacks are executed sequentially, it is
	 * guaranteed that this function will never run twice in parallel for
	 * the same PM domain, so it is not necessary to use locking here.
1300 1301 1302
	 *
	 * At this point suspended_count == 0 means we are being run for the
	 * first time for the given domain in the present cycle.
1303
	 */
1304
	if (genpd->suspended_count++ == 0) {
1305
		/*
1306
		 * The boot kernel might put the domain into arbitrary state,
1307 1308
		 * so make it appear as powered off to pm_genpd_sync_poweron(),
		 * so that it tries to power it on in case it was really off.
1309
		 */
1310 1311 1312 1313 1314 1315
		genpd->status = GPD_STATE_POWER_OFF;
		if (genpd->suspend_power_off) {
			/*
			 * If the domain was off before the hibernation, make
			 * sure it will be off going forward.
			 */
1316
			genpd_power_off(genpd, true);
1317 1318 1319

			return 0;
		}
1320 1321
	}

1322 1323 1324
	if (genpd->suspend_power_off)
		return 0;

1325
	pm_genpd_sync_poweron(genpd, true);
1326

1327
	return genpd_start_dev(genpd, dev);
1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359
}

/**
 * pm_genpd_complete - Complete power transition of a device in a power domain.
 * @dev: Device to complete the transition of.
 *
 * Complete a power transition of a device (during a system-wide power
 * transition) under the assumption that its pm_domain field points to the
 * domain member of an object of type struct generic_pm_domain representing
 * a power domain consisting of I/O devices.
 */
static void pm_genpd_complete(struct device *dev)
{
	struct generic_pm_domain *genpd;
	bool run_complete;

	dev_dbg(dev, "%s()\n", __func__);

	genpd = dev_to_genpd(dev);
	if (IS_ERR(genpd))
		return;

	mutex_lock(&genpd->lock);

	run_complete = !genpd->suspend_power_off;
	if (--genpd->prepared_count == 0)
		genpd->suspend_power_off = false;

	mutex_unlock(&genpd->lock);

	if (run_complete) {
		pm_generic_complete(dev);
1360
		pm_runtime_set_active(dev);
1361
		pm_runtime_enable(dev);
1362
		pm_request_idle(dev);
1363 1364 1365
	}
}

1366
/**
1367
 * genpd_syscore_switch - Switch power during system core suspend or resume.
1368 1369 1370 1371 1372
 * @dev: Device that normally is marked as "always on" to switch power for.
 *
 * This routine may only be called during the system core (syscore) suspend or
 * resume phase for devices whose "always on" flags are set.
 */
1373
static void genpd_syscore_switch(struct device *dev, bool suspend)
1374 1375 1376 1377 1378 1379 1380 1381 1382
{
	struct generic_pm_domain *genpd;

	genpd = dev_to_genpd(dev);
	if (!pm_genpd_present(genpd))
		return;

	if (suspend) {
		genpd->suspended_count++;
1383
		pm_genpd_sync_poweroff(genpd, false);
1384
	} else {
1385
		pm_genpd_sync_poweron(genpd, false);
1386 1387 1388
		genpd->suspended_count--;
	}
}
1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400

void pm_genpd_syscore_poweroff(struct device *dev)
{
	genpd_syscore_switch(dev, true);
}
EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweroff);

void pm_genpd_syscore_poweron(struct device *dev)
{
	genpd_syscore_switch(dev, false);
}
EXPORT_SYMBOL_GPL(pm_genpd_syscore_poweron);
1401

1402
#else /* !CONFIG_PM_SLEEP */
1403 1404 1405

#define pm_genpd_prepare		NULL
#define pm_genpd_suspend		NULL
1406
#define pm_genpd_suspend_late		NULL
1407
#define pm_genpd_suspend_noirq		NULL
1408
#define pm_genpd_resume_early		NULL
1409 1410 1411
#define pm_genpd_resume_noirq		NULL
#define pm_genpd_resume			NULL
#define pm_genpd_freeze			NULL
1412
#define pm_genpd_freeze_late		NULL
1413
#define pm_genpd_freeze_noirq		NULL
1414
#define pm_genpd_thaw_early		NULL
1415 1416 1417 1418 1419 1420 1421
#define pm_genpd_thaw_noirq		NULL
#define pm_genpd_thaw			NULL
#define pm_genpd_restore_noirq		NULL
#define pm_genpd_complete		NULL

#endif /* CONFIG_PM_SLEEP */

1422 1423 1424
static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
					struct generic_pm_domain *genpd,
					struct gpd_timing_data *td)
1425 1426
{
	struct generic_pm_domain_data *gpd_data;
1427 1428 1429 1430 1431
	int ret;

	ret = dev_pm_get_subsys_data(dev);
	if (ret)
		return ERR_PTR(ret);
1432 1433

	gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
1434 1435 1436 1437
	if (!gpd_data) {
		ret = -ENOMEM;
		goto err_put;
	}
1438

1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459
	if (td)
		gpd_data->td = *td;

	gpd_data->base.dev = dev;
	gpd_data->need_restore = -1;
	gpd_data->td.constraint_changed = true;
	gpd_data->td.effective_constraint_ns = -1;
	gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier;

	spin_lock_irq(&dev->power.lock);

	if (dev->power.subsys_data->domain_data) {
		ret = -EINVAL;
		goto err_free;
	}

	dev->power.subsys_data->domain_data = &gpd_data->base;
	dev->pm_domain = &genpd->domain;

	spin_unlock_irq(&dev->power.lock);

1460
	return gpd_data;
1461

1462 1463 1464
 err_free:
	spin_unlock_irq(&dev->power.lock);
	kfree(gpd_data);
1465 1466 1467
 err_put:
	dev_pm_put_subsys_data(dev);
	return ERR_PTR(ret);
1468 1469
}

1470 1471
static void genpd_free_dev_data(struct device *dev,
				struct generic_pm_domain_data *gpd_data)
1472
{
1473 1474 1475 1476 1477 1478 1479
	spin_lock_irq(&dev->power.lock);

	dev->pm_domain = NULL;
	dev->power.subsys_data->domain_data = NULL;

	spin_unlock_irq(&dev->power.lock);

1480
	kfree(gpd_data);
1481
	dev_pm_put_subsys_data(dev);
1482 1483
}

1484
/**
1485
 * __pm_genpd_add_device - Add a device to an I/O PM domain.
1486 1487
 * @genpd: PM domain to add the device to.
 * @dev: Device to be added.
1488
 * @td: Set of PM QoS timing parameters to attach to the device.
1489
 */
1490 1491
int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
			  struct gpd_timing_data *td)
1492
{
1493
	struct generic_pm_domain_data *gpd_data;
1494 1495 1496 1497 1498 1499 1500
	int ret = 0;

	dev_dbg(dev, "%s()\n", __func__);

	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
		return -EINVAL;

1501
	gpd_data = genpd_alloc_dev_data(dev, genpd, td);
1502 1503
	if (IS_ERR(gpd_data))
		return PTR_ERR(gpd_data);
1504

1505
	genpd_acquire_lock(genpd);
1506

1507 1508 1509 1510 1511
	if (genpd->prepared_count > 0) {
		ret = -EAGAIN;
		goto out;
	}

1512 1513 1514
	ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
	if (ret)
		goto out;
1515

1516 1517 1518
	genpd->device_count++;
	genpd->max_off_time_changed = true;

1519
	list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
1520

1521
 out:
1522
	genpd_release_lock(genpd);
1523

1524 1525 1526 1527
	if (ret)
		genpd_free_dev_data(dev, gpd_data);
	else
		dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1528

1529 1530 1531
	return ret;
}

1532 1533 1534 1535 1536 1537 1538 1539 1540
/**
 * __pm_genpd_name_add_device - Find I/O PM domain and add a device to it.
 * @domain_name: Name of the PM domain to add the device to.
 * @dev: Device to be added.
 * @td: Set of PM QoS timing parameters to attach to the device.
 */
int __pm_genpd_name_add_device(const char *domain_name, struct device *dev,
			       struct gpd_timing_data *td)
{
1541
	return __pm_genpd_add_device(pm_genpd_lookup_name(domain_name), dev, td);
1542 1543
}

1544 1545 1546 1547 1548 1549 1550 1551
/**
 * pm_genpd_remove_device - Remove a device from an I/O PM domain.
 * @genpd: PM domain to remove the device from.
 * @dev: Device to be removed.
 */
int pm_genpd_remove_device(struct generic_pm_domain *genpd,
			   struct device *dev)
{
1552
	struct generic_pm_domain_data *gpd_data;
1553
	struct pm_domain_data *pdd;
1554
	int ret = 0;
1555 1556 1557

	dev_dbg(dev, "%s()\n", __func__);

1558
	if (!genpd || genpd != pm_genpd_lookup_dev(dev))
1559 1560
		return -EINVAL;

1561 1562 1563 1564 1565
	/* The above validation also means we have existing domain_data. */
	pdd = dev->power.subsys_data->domain_data;
	gpd_data = to_gpd_data(pdd);
	dev_pm_qos_remove_notifier(dev, &gpd_data->nb);

1566
	genpd_acquire_lock(genpd);
1567

1568 1569 1570 1571 1572
	if (genpd->prepared_count > 0) {
		ret = -EAGAIN;
		goto out;
	}

1573 1574 1575
	genpd->device_count--;
	genpd->max_off_time_changed = true;

1576
	if (genpd->detach_dev)
1577
		genpd->detach_dev(genpd, dev);
1578

1579
	list_del_init(&pdd->list_node);
1580 1581 1582

	genpd_release_lock(genpd);

1583
	genpd_free_dev_data(dev, gpd_data);
1584

1585
	return 0;
1586

1587
 out:
1588
	genpd_release_lock(genpd);
1589
	dev_pm_qos_add_notifier(dev, &gpd_data->nb);
1590 1591 1592 1593 1594 1595 1596

	return ret;
}

/**
 * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
 * @genpd: Master PM domain to add the subdomain to.
1597
 * @subdomain: Subdomain to be added.
1598 1599
 */
int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
1600
			   struct generic_pm_domain *subdomain)
1601
{
1602
	struct gpd_link *link;
1603 1604
	int ret = 0;

1605 1606
	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
	    || genpd == subdomain)
1607 1608
		return -EINVAL;

1609 1610
 start:
	genpd_acquire_lock(genpd);
1611
	mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);
1612

1613 1614 1615
	if (subdomain->status != GPD_STATE_POWER_OFF
	    && subdomain->status != GPD_STATE_ACTIVE) {
		mutex_unlock(&subdomain->lock);
1616 1617 1618 1619 1620
		genpd_release_lock(genpd);
		goto start;
	}

	if (genpd->status == GPD_STATE_POWER_OFF
1621
	    &&  subdomain->status != GPD_STATE_POWER_OFF) {
1622 1623 1624 1625
		ret = -EINVAL;
		goto out;
	}

1626
	list_for_each_entry(link, &genpd->master_links, master_node) {
1627
		if (link->slave == subdomain && link->master == genpd) {
1628 1629 1630 1631 1632
			ret = -EINVAL;
			goto out;
		}
	}

1633 1634 1635 1636 1637 1638 1639
	link = kzalloc(sizeof(*link), GFP_KERNEL);
	if (!link) {
		ret = -ENOMEM;
		goto out;
	}
	link->master = genpd;
	list_add_tail(&link->master_node, &genpd->master_links);
1640 1641 1642
	link->slave = subdomain;
	list_add_tail(&link->slave_node, &subdomain->slave_links);
	if (subdomain->status != GPD_STATE_POWER_OFF)
1643
		genpd_sd_counter_inc(genpd);
1644 1645

 out:
1646
	mutex_unlock(&subdomain->lock);
1647
	genpd_release_lock(genpd);
1648 1649 1650 1651

	return ret;
}

1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680
/**
 * pm_genpd_add_subdomain_names - Add a subdomain to an I/O PM domain.
 * @master_name: Name of the master PM domain to add the subdomain to.
 * @subdomain_name: Name of the subdomain to be added.
 */
int pm_genpd_add_subdomain_names(const char *master_name,
				 const char *subdomain_name)
{
	struct generic_pm_domain *master = NULL, *subdomain = NULL, *gpd;

	if (IS_ERR_OR_NULL(master_name) || IS_ERR_OR_NULL(subdomain_name))
		return -EINVAL;

	mutex_lock(&gpd_list_lock);
	list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
		if (!master && !strcmp(gpd->name, master_name))
			master = gpd;

		if (!subdomain && !strcmp(gpd->name, subdomain_name))
			subdomain = gpd;

		if (master && subdomain)
			break;
	}
	mutex_unlock(&gpd_list_lock);

	return pm_genpd_add_subdomain(master, subdomain);
}

1681 1682 1683
/**
 * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
 * @genpd: Master PM domain to remove the subdomain from.
1684
 * @subdomain: Subdomain to be removed.
1685 1686
 */
int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
1687
			      struct generic_pm_domain *subdomain)
1688
{
1689
	struct gpd_link *link;
1690 1691
	int ret = -EINVAL;

1692
	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
1693 1694
		return -EINVAL;

1695 1696
 start:
	genpd_acquire_lock(genpd);
1697

1698 1699
	list_for_each_entry(link, &genpd->master_links, master_node) {
		if (link->slave != subdomain)
1700 1701 1702 1703
			continue;

		mutex_lock_nested(&subdomain->lock, SINGLE_DEPTH_NESTING);

1704 1705 1706 1707 1708 1709 1710
		if (subdomain->status != GPD_STATE_POWER_OFF
		    && subdomain->status != GPD_STATE_ACTIVE) {
			mutex_unlock(&subdomain->lock);
			genpd_release_lock(genpd);
			goto start;
		}

1711 1712 1713
		list_del(&link->master_node);
		list_del(&link->slave_node);
		kfree(link);
1714
		if (subdomain->status != GPD_STATE_POWER_OFF)
1715 1716 1717 1718 1719 1720 1721 1722
			genpd_sd_counter_dec(genpd);

		mutex_unlock(&subdomain->lock);

		ret = 0;
		break;
	}

1723
	genpd_release_lock(genpd);
1724 1725 1726 1727

	return ret;
}

1728 1729 1730 1731 1732 1733 1734 1735 1736 1737
/**
 * pm_genpd_attach_cpuidle - Connect the given PM domain with cpuidle.
 * @genpd: PM domain to be connected with cpuidle.
 * @state: cpuidle state this domain can disable/enable.
 *
 * Make a PM domain behave as though it contained a CPU core, that is, instead
 * of calling its power down routine it will enable the given cpuidle state so
 * that the cpuidle subsystem can power it down (if possible and desirable).
 */
int pm_genpd_attach_cpuidle(struct generic_pm_domain *genpd, int state)
1738 1739
{
	struct cpuidle_driver *cpuidle_drv;
1740
	struct gpd_cpuidle_data *cpuidle_data;
1741 1742 1743 1744 1745 1746 1747 1748
	struct cpuidle_state *idle_state;
	int ret = 0;

	if (IS_ERR_OR_NULL(genpd) || state < 0)
		return -EINVAL;

	genpd_acquire_lock(genpd);

1749
	if (genpd->cpuidle_data) {
1750 1751 1752
		ret = -EEXIST;
		goto out;
	}
1753 1754
	cpuidle_data = kzalloc(sizeof(*cpuidle_data), GFP_KERNEL);
	if (!cpuidle_data) {
1755 1756 1757 1758 1759 1760
		ret = -ENOMEM;
		goto out;
	}
	cpuidle_drv = cpuidle_driver_ref();
	if (!cpuidle_drv) {
		ret = -ENODEV;
1761
		goto err_drv;
1762 1763 1764 1765 1766 1767 1768 1769 1770 1771
	}
	if (cpuidle_drv->state_count <= state) {
		ret = -EINVAL;
		goto err;
	}
	idle_state = &cpuidle_drv->states[state];
	if (!idle_state->disabled) {
		ret = -EAGAIN;
		goto err;
	}
1772 1773 1774
	cpuidle_data->idle_state = idle_state;
	cpuidle_data->saved_exit_latency = idle_state->exit_latency;
	genpd->cpuidle_data = cpuidle_data;
1775 1776 1777 1778 1779 1780 1781 1782
	genpd_recalc_cpu_exit_latency(genpd);

 out:
	genpd_release_lock(genpd);
	return ret;

 err:
	cpuidle_driver_unref();
1783 1784

 err_drv:
1785
	kfree(cpuidle_data);
1786 1787 1788
	goto out;
}

1789 1790 1791 1792 1793 1794 1795 1796 1797 1798
/**
 * pm_genpd_name_attach_cpuidle - Find PM domain and connect cpuidle to it.
 * @name: Name of the domain to connect to cpuidle.
 * @state: cpuidle state this domain can manipulate.
 */
int pm_genpd_name_attach_cpuidle(const char *name, int state)
{
	return pm_genpd_attach_cpuidle(pm_genpd_lookup_name(name), state);
}

1799 1800 1801 1802 1803 1804 1805 1806
/**
 * pm_genpd_detach_cpuidle - Remove the cpuidle connection from a PM domain.
 * @genpd: PM domain to remove the cpuidle connection from.
 *
 * Remove the cpuidle connection set up by pm_genpd_attach_cpuidle() from the
 * given PM domain.
 */
int pm_genpd_detach_cpuidle(struct generic_pm_domain *genpd)
1807
{
1808
	struct gpd_cpuidle_data *cpuidle_data;
1809 1810 1811 1812 1813 1814 1815 1816
	struct cpuidle_state *idle_state;
	int ret = 0;

	if (IS_ERR_OR_NULL(genpd))
		return -EINVAL;

	genpd_acquire_lock(genpd);

1817 1818
	cpuidle_data = genpd->cpuidle_data;
	if (!cpuidle_data) {
1819 1820 1821
		ret = -ENODEV;
		goto out;
	}
1822
	idle_state = cpuidle_data->idle_state;
1823 1824 1825 1826
	if (!idle_state->disabled) {
		ret = -EAGAIN;
		goto out;
	}
1827
	idle_state->exit_latency = cpuidle_data->saved_exit_latency;
1828
	cpuidle_driver_unref();
1829 1830
	genpd->cpuidle_data = NULL;
	kfree(cpuidle_data);
1831 1832 1833 1834 1835 1836

 out:
	genpd_release_lock(genpd);
	return ret;
}

1837 1838 1839 1840 1841 1842 1843 1844 1845
/**
 * pm_genpd_name_detach_cpuidle - Find PM domain and disconnect cpuidle from it.
 * @name: Name of the domain to disconnect cpuidle from.
 */
int pm_genpd_name_detach_cpuidle(const char *name)
{
	return pm_genpd_detach_cpuidle(pm_genpd_lookup_name(name));
}

1846 1847
/* Default device callbacks for generic PM domains. */

1848
/**
1849
 * pm_genpd_default_save_state - Default "save device state" for PM domains.
1850 1851 1852 1853 1854 1855
 * @dev: Device to handle.
 */
static int pm_genpd_default_save_state(struct device *dev)
{
	int (*cb)(struct device *__dev);

1856 1857 1858 1859 1860 1861 1862 1863
	if (dev->type && dev->type->pm)
		cb = dev->type->pm->runtime_suspend;
	else if (dev->class && dev->class->pm)
		cb = dev->class->pm->runtime_suspend;
	else if (dev->bus && dev->bus->pm)
		cb = dev->bus->pm->runtime_suspend;
	else
		cb = NULL;
1864

1865 1866 1867 1868
	if (!cb && dev->driver && dev->driver->pm)
		cb = dev->driver->pm->runtime_suspend;

	return cb ? cb(dev) : 0;
1869 1870 1871
}

/**
1872
 * pm_genpd_default_restore_state - Default PM domains "restore device state".
1873 1874 1875 1876 1877 1878
 * @dev: Device to handle.
 */
static int pm_genpd_default_restore_state(struct device *dev)
{
	int (*cb)(struct device *__dev);

1879 1880 1881 1882 1883 1884 1885 1886
	if (dev->type && dev->type->pm)
		cb = dev->type->pm->runtime_resume;
	else if (dev->class && dev->class->pm)
		cb = dev->class->pm->runtime_resume;
	else if (dev->bus && dev->bus->pm)
		cb = dev->bus->pm->runtime_resume;
	else
		cb = NULL;
1887

1888 1889 1890 1891
	if (!cb && dev->driver && dev->driver->pm)
		cb = dev->driver->pm->runtime_resume;

	return cb ? cb(dev) : 0;
1892 1893
}

1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905
/**
 * pm_genpd_init - Initialize a generic I/O PM domain object.
 * @genpd: PM domain object to initialize.
 * @gov: PM domain governor to associate with the domain (may be NULL).
 * @is_off: Initial value of the domain's power_is_off field.
 */
void pm_genpd_init(struct generic_pm_domain *genpd,
		   struct dev_power_governor *gov, bool is_off)
{
	if (IS_ERR_OR_NULL(genpd))
		return;

1906 1907
	INIT_LIST_HEAD(&genpd->master_links);
	INIT_LIST_HEAD(&genpd->slave_links);
1908 1909 1910 1911 1912
	INIT_LIST_HEAD(&genpd->dev_list);
	mutex_init(&genpd->lock);
	genpd->gov = gov;
	INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
	genpd->in_progress = 0;
1913
	atomic_set(&genpd->sd_count, 0);
1914 1915
	genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
	init_waitqueue_head(&genpd->status_wait_queue);
1916 1917
	genpd->poweroff_task = NULL;
	genpd->resume_count = 0;
1918
	genpd->device_count = 0;
1919
	genpd->max_off_time_ns = -1;
1920
	genpd->max_off_time_changed = true;
1921 1922
	genpd->domain.ops.runtime_suspend = pm_genpd_runtime_suspend;
	genpd->domain.ops.runtime_resume = pm_genpd_runtime_resume;
1923 1924
	genpd->domain.ops.prepare = pm_genpd_prepare;
	genpd->domain.ops.suspend = pm_genpd_suspend;
1925
	genpd->domain.ops.suspend_late = pm_genpd_suspend_late;
1926 1927
	genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq;
	genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq;
1928
	genpd->domain.ops.resume_early = pm_genpd_resume_early;
1929 1930
	genpd->domain.ops.resume = pm_genpd_resume;
	genpd->domain.ops.freeze = pm_genpd_freeze;
1931
	genpd->domain.ops.freeze_late = pm_genpd_freeze_late;
1932 1933
	genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq;
	genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq;
1934
	genpd->domain.ops.thaw_early = pm_genpd_thaw_early;
1935
	genpd->domain.ops.thaw = pm_genpd_thaw;
1936
	genpd->domain.ops.poweroff = pm_genpd_suspend;
1937
	genpd->domain.ops.poweroff_late = pm_genpd_suspend_late;
1938
	genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq;
1939
	genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq;
1940
	genpd->domain.ops.restore_early = pm_genpd_resume_early;
1941
	genpd->domain.ops.restore = pm_genpd_resume;
1942
	genpd->domain.ops.complete = pm_genpd_complete;
1943 1944
	genpd->dev_ops.save_state = pm_genpd_default_save_state;
	genpd->dev_ops.restore_state = pm_genpd_default_restore_state;
1945 1946 1947 1948 1949 1950

	if (genpd->flags & GENPD_FLAG_PM_CLK) {
		genpd->dev_ops.stop = pm_clk_suspend;
		genpd->dev_ops.start = pm_clk_resume;
	}

1951 1952 1953 1954
	mutex_lock(&gpd_list_lock);
	list_add(&genpd->gpd_list_node, &gpd_list);
	mutex_unlock(&gpd_list_lock);
}
1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103

#ifdef CONFIG_PM_GENERIC_DOMAINS_OF
/*
 * Device Tree based PM domain providers.
 *
 * The code below implements generic device tree based PM domain providers that
 * bind device tree nodes with generic PM domains registered in the system.
 *
 * Any driver that registers generic PM domains and needs to support binding of
 * devices to these domains is supposed to register a PM domain provider, which
 * maps a PM domain specifier retrieved from the device tree to a PM domain.
 *
 * Two simple mapping functions have been provided for convenience:
 *  - __of_genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
 *  - __of_genpd_xlate_onecell() for mapping of multiple PM domains per node by
 *    index.
 */

/**
 * struct of_genpd_provider - PM domain provider registration structure
 * @link: Entry in global list of PM domain providers
 * @node: Pointer to device tree node of PM domain provider
 * @xlate: Provider-specific xlate callback mapping a set of specifier cells
 *         into a PM domain.
 * @data: context pointer to be passed into @xlate callback
 */
struct of_genpd_provider {
	struct list_head link;
	struct device_node *node;
	genpd_xlate_t xlate;
	void *data;
};

/* List of registered PM domain providers. */
static LIST_HEAD(of_genpd_providers);
/* Mutex to protect the list above. */
static DEFINE_MUTEX(of_genpd_mutex);

/**
 * __of_genpd_xlate_simple() - Xlate function for direct node-domain mapping
 * @genpdspec: OF phandle args to map into a PM domain
 * @data: xlate function private data - pointer to struct generic_pm_domain
 *
 * This is a generic xlate function that can be used to model PM domains that
 * have their own device tree nodes. The private data of xlate function needs
 * to be a valid pointer to struct generic_pm_domain.
 */
struct generic_pm_domain *__of_genpd_xlate_simple(
					struct of_phandle_args *genpdspec,
					void *data)
{
	if (genpdspec->args_count != 0)
		return ERR_PTR(-EINVAL);
	return data;
}
EXPORT_SYMBOL_GPL(__of_genpd_xlate_simple);

/**
 * __of_genpd_xlate_onecell() - Xlate function using a single index.
 * @genpdspec: OF phandle args to map into a PM domain
 * @data: xlate function private data - pointer to struct genpd_onecell_data
 *
 * This is a generic xlate function that can be used to model simple PM domain
 * controllers that have one device tree node and provide multiple PM domains.
 * A single cell is used as an index into an array of PM domains specified in
 * the genpd_onecell_data struct when registering the provider.
 */
struct generic_pm_domain *__of_genpd_xlate_onecell(
					struct of_phandle_args *genpdspec,
					void *data)
{
	struct genpd_onecell_data *genpd_data = data;
	unsigned int idx = genpdspec->args[0];

	if (genpdspec->args_count != 1)
		return ERR_PTR(-EINVAL);

	if (idx >= genpd_data->num_domains) {
		pr_err("%s: invalid domain index %u\n", __func__, idx);
		return ERR_PTR(-EINVAL);
	}

	if (!genpd_data->domains[idx])
		return ERR_PTR(-ENOENT);

	return genpd_data->domains[idx];
}
EXPORT_SYMBOL_GPL(__of_genpd_xlate_onecell);

/**
 * __of_genpd_add_provider() - Register a PM domain provider for a node
 * @np: Device node pointer associated with the PM domain provider.
 * @xlate: Callback for decoding PM domain from phandle arguments.
 * @data: Context pointer for @xlate callback.
 */
int __of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate,
			void *data)
{
	struct of_genpd_provider *cp;

	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
	if (!cp)
		return -ENOMEM;

	cp->node = of_node_get(np);
	cp->data = data;
	cp->xlate = xlate;

	mutex_lock(&of_genpd_mutex);
	list_add(&cp->link, &of_genpd_providers);
	mutex_unlock(&of_genpd_mutex);
	pr_debug("Added domain provider from %s\n", np->full_name);

	return 0;
}
EXPORT_SYMBOL_GPL(__of_genpd_add_provider);

/**
 * of_genpd_del_provider() - Remove a previously registered PM domain provider
 * @np: Device node pointer associated with the PM domain provider
 */
void of_genpd_del_provider(struct device_node *np)
{
	struct of_genpd_provider *cp;

	mutex_lock(&of_genpd_mutex);
	list_for_each_entry(cp, &of_genpd_providers, link) {
		if (cp->node == np) {
			list_del(&cp->link);
			of_node_put(cp->node);
			kfree(cp);
			break;
		}
	}
	mutex_unlock(&of_genpd_mutex);
}
EXPORT_SYMBOL_GPL(of_genpd_del_provider);

/**
 * of_genpd_get_from_provider() - Look-up PM domain
 * @genpdspec: OF phandle args to use for look-up
 *
 * Looks for a PM domain provider under the node specified by @genpdspec and if
 * found, uses xlate function of the provider to map phandle args to a PM
 * domain.
 *
 * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR()
 * on failure.
 */
2104
struct generic_pm_domain *of_genpd_get_from_provider(
2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
					struct of_phandle_args *genpdspec)
{
	struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
	struct of_genpd_provider *provider;

	mutex_lock(&of_genpd_mutex);

	/* Check if we have such a provider in our array */
	list_for_each_entry(provider, &of_genpd_providers, link) {
		if (provider->node == genpdspec->np)
			genpd = provider->xlate(genpdspec, provider->data);
		if (!IS_ERR(genpd))
			break;
	}

	mutex_unlock(&of_genpd_mutex);

	return genpd;
}
2124
EXPORT_SYMBOL_GPL(of_genpd_get_from_provider);
2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135

/**
 * genpd_dev_pm_detach - Detach a device from its PM domain.
 * @dev: Device to attach.
 * @power_off: Currently not used
 *
 * Try to locate a corresponding generic PM domain, which the device was
 * attached to previously. If such is found, the device is detached from it.
 */
static void genpd_dev_pm_detach(struct device *dev, bool power_off)
{
2136
	struct generic_pm_domain *pd;
2137
	unsigned int i;
2138 2139
	int ret = 0;

2140
	pd = pm_genpd_lookup_dev(dev);
2141 2142 2143 2144 2145
	if (!pd)
		return;

	dev_dbg(dev, "removing from PM domain %s\n", pd->name);

2146
	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2147 2148 2149
		ret = pm_genpd_remove_device(pd, dev);
		if (ret != -EAGAIN)
			break;
2150 2151

		mdelay(i);
2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164
		cond_resched();
	}

	if (ret < 0) {
		dev_err(dev, "failed to remove from PM domain %s: %d",
			pd->name, ret);
		return;
	}

	/* Check if PM domain can be powered off after removing this device. */
	genpd_queue_power_off_work(pd);
}

2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175
static void genpd_dev_pm_sync(struct device *dev)
{
	struct generic_pm_domain *pd;

	pd = dev_to_genpd(dev);
	if (IS_ERR(pd))
		return;

	genpd_queue_power_off_work(pd);
}

2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191
/**
 * genpd_dev_pm_attach - Attach a device to its PM domain using DT.
 * @dev: Device to attach.
 *
 * Parse device's OF node to find a PM domain specifier. If such is found,
 * attaches the device to retrieved pm_domain ops.
 *
 * Both generic and legacy Samsung-specific DT bindings are supported to keep
 * backwards compatibility with existing DTBs.
 *
 * Returns 0 on successfully attached PM domain or negative error code.
 */
int genpd_dev_pm_attach(struct device *dev)
{
	struct of_phandle_args pd_args;
	struct generic_pm_domain *pd;
2192
	unsigned int i;
2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227
	int ret;

	if (!dev->of_node)
		return -ENODEV;

	if (dev->pm_domain)
		return -EEXIST;

	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
					"#power-domain-cells", 0, &pd_args);
	if (ret < 0) {
		if (ret != -ENOENT)
			return ret;

		/*
		 * Try legacy Samsung-specific bindings
		 * (for backwards compatibility of DT ABI)
		 */
		pd_args.args_count = 0;
		pd_args.np = of_parse_phandle(dev->of_node,
						"samsung,power-domain", 0);
		if (!pd_args.np)
			return -ENOENT;
	}

	pd = of_genpd_get_from_provider(&pd_args);
	if (IS_ERR(pd)) {
		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
			__func__, PTR_ERR(pd));
		of_node_put(dev->of_node);
		return PTR_ERR(pd);
	}

	dev_dbg(dev, "adding to PM domain %s\n", pd->name);

2228
	for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
2229 2230 2231
		ret = pm_genpd_add_device(pd, dev);
		if (ret != -EAGAIN)
			break;
2232 2233

		mdelay(i);
2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244
		cond_resched();
	}

	if (ret < 0) {
		dev_err(dev, "failed to add to PM domain %s: %d",
			pd->name, ret);
		of_node_put(dev->of_node);
		return ret;
	}

	dev->pm_domain->detach = genpd_dev_pm_detach;
2245
	dev->pm_domain->sync = genpd_dev_pm_sync;
2246
	pm_genpd_poweron(pd);
2247 2248 2249 2250

	return 0;
}
EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
2251
#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266


/***        debugfs support        ***/

#ifdef CONFIG_PM_ADVANCED_DEBUG
#include <linux/pm.h>
#include <linux/device.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/kobject.h>
static struct dentry *pm_genpd_debugfs_dir;

/*
 * TODO: This function is a slightly modified version of rtpm_status_show
2267
 * from sysfs.c, so generalize it.
2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291
 */
static void rtpm_status_str(struct seq_file *s, struct device *dev)
{
	static const char * const status_lookup[] = {
		[RPM_ACTIVE] = "active",
		[RPM_RESUMING] = "resuming",
		[RPM_SUSPENDED] = "suspended",
		[RPM_SUSPENDING] = "suspending"
	};
	const char *p = "";

	if (dev->power.runtime_error)
		p = "error";
	else if (dev->power.disable_depth)
		p = "unsupported";
	else if (dev->power.runtime_status < ARRAY_SIZE(status_lookup))
		p = status_lookup[dev->power.runtime_status];
	else
		WARN_ON(1);

	seq_puts(s, p);
}

static int pm_genpd_summary_one(struct seq_file *s,
2292
				struct generic_pm_domain *genpd)
2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305
{
	static const char * const status_lookup[] = {
		[GPD_STATE_ACTIVE] = "on",
		[GPD_STATE_WAIT_MASTER] = "wait-master",
		[GPD_STATE_BUSY] = "busy",
		[GPD_STATE_REPEAT] = "off-in-progress",
		[GPD_STATE_POWER_OFF] = "off"
	};
	struct pm_domain_data *pm_data;
	const char *kobj_path;
	struct gpd_link *link;
	int ret;

2306
	ret = mutex_lock_interruptible(&genpd->lock);
2307 2308 2309
	if (ret)
		return -ERESTARTSYS;

2310
	if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
2311
		goto exit;
2312
	seq_printf(s, "%-30s  %-15s  ", genpd->name, status_lookup[genpd->status]);
2313 2314 2315 2316

	/*
	 * Modifications on the list require holding locks on both
	 * master and slave, so we are safe.
2317
	 * Also genpd->name is immutable.
2318
	 */
2319
	list_for_each_entry(link, &genpd->master_links, master_node) {
2320
		seq_printf(s, "%s", link->slave->name);
2321
		if (!list_is_last(&link->master_node, &genpd->master_links))
2322 2323 2324
			seq_puts(s, ", ");
	}

2325
	list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
		kobj_path = kobject_get_path(&pm_data->dev->kobj, GFP_KERNEL);
		if (kobj_path == NULL)
			continue;

		seq_printf(s, "\n    %-50s  ", kobj_path);
		rtpm_status_str(s, pm_data->dev);
		kfree(kobj_path);
	}

	seq_puts(s, "\n");
exit:
2337
	mutex_unlock(&genpd->lock);
2338 2339 2340 2341 2342 2343

	return 0;
}

static int pm_genpd_summary_show(struct seq_file *s, void *data)
{
2344
	struct generic_pm_domain *genpd;
2345 2346 2347 2348 2349 2350 2351 2352 2353 2354
	int ret = 0;

	seq_puts(s, "    domain                      status         slaves\n");
	seq_puts(s, "           /device                                      runtime status\n");
	seq_puts(s, "----------------------------------------------------------------------\n");

	ret = mutex_lock_interruptible(&gpd_list_lock);
	if (ret)
		return -ERESTARTSYS;

2355 2356
	list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
		ret = pm_genpd_summary_one(s, genpd);
2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400
		if (ret)
			break;
	}
	mutex_unlock(&gpd_list_lock);

	return ret;
}

static int pm_genpd_summary_open(struct inode *inode, struct file *file)
{
	return single_open(file, pm_genpd_summary_show, NULL);
}

static const struct file_operations pm_genpd_summary_fops = {
	.open = pm_genpd_summary_open,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static int __init pm_genpd_debug_init(void)
{
	struct dentry *d;

	pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);

	if (!pm_genpd_debugfs_dir)
		return -ENOMEM;

	d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
			pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops);
	if (!d)
		return -ENOMEM;

	return 0;
}
late_initcall(pm_genpd_debug_init);

static void __exit pm_genpd_debug_exit(void)
{
	debugfs_remove_recursive(pm_genpd_debugfs_dir);
}
__exitcall(pm_genpd_debug_exit);
#endif /* CONFIG_PM_ADVANCED_DEBUG */