summaryrefslogtreecommitdiffstats
path: root/drivers/base/power/domain.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/power/domain.c')
-rw-r--r--drivers/base/power/domain.c2928
1 files changed, 2928 insertions, 0 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
new file mode 100644
index 000000000..52c292d09
--- /dev/null
+++ b/drivers/base/power/domain.c
@@ -0,0 +1,2928 @@
+/*
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_clock.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/suspend.h>
+#include <linux/export.h>
+
+#include "power.h"
+
+#define GENPD_RETRY_MAX_MS 250 /* Approximate */
+
+#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; \
+})
+
+static LIST_HEAD(gpd_list);
+static DEFINE_MUTEX(gpd_list_lock);
+
+struct genpd_lock_ops {
+ void (*lock)(struct generic_pm_domain *genpd);
+ void (*lock_nested)(struct generic_pm_domain *genpd, int depth);
+ int (*lock_interruptible)(struct generic_pm_domain *genpd);
+ void (*unlock)(struct generic_pm_domain *genpd);
+};
+
+static void genpd_lock_mtx(struct generic_pm_domain *genpd)
+{
+ mutex_lock(&genpd->mlock);
+}
+
+static void genpd_lock_nested_mtx(struct generic_pm_domain *genpd,
+ int depth)
+{
+ mutex_lock_nested(&genpd->mlock, depth);
+}
+
+static int genpd_lock_interruptible_mtx(struct generic_pm_domain *genpd)
+{
+ return mutex_lock_interruptible(&genpd->mlock);
+}
+
+static void genpd_unlock_mtx(struct generic_pm_domain *genpd)
+{
+ return mutex_unlock(&genpd->mlock);
+}
+
+static const struct genpd_lock_ops genpd_mtx_ops = {
+ .lock = genpd_lock_mtx,
+ .lock_nested = genpd_lock_nested_mtx,
+ .lock_interruptible = genpd_lock_interruptible_mtx,
+ .unlock = genpd_unlock_mtx,
+};
+
+static void genpd_lock_spin(struct generic_pm_domain *genpd)
+ __acquires(&genpd->slock)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&genpd->slock, flags);
+ genpd->lock_flags = flags;
+}
+
+static void genpd_lock_nested_spin(struct generic_pm_domain *genpd,
+ int depth)
+ __acquires(&genpd->slock)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave_nested(&genpd->slock, flags, depth);
+ genpd->lock_flags = flags;
+}
+
+static int genpd_lock_interruptible_spin(struct generic_pm_domain *genpd)
+ __acquires(&genpd->slock)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&genpd->slock, flags);
+ genpd->lock_flags = flags;
+ return 0;
+}
+
+static void genpd_unlock_spin(struct generic_pm_domain *genpd)
+ __releases(&genpd->slock)
+{
+ spin_unlock_irqrestore(&genpd->slock, genpd->lock_flags);
+}
+
+static const struct genpd_lock_ops genpd_spin_ops = {
+ .lock = genpd_lock_spin,
+ .lock_nested = genpd_lock_nested_spin,
+ .lock_interruptible = genpd_lock_interruptible_spin,
+ .unlock = genpd_unlock_spin,
+};
+
+#define genpd_lock(p) p->lock_ops->lock(p)
+#define genpd_lock_nested(p, d) p->lock_ops->lock_nested(p, d)
+#define genpd_lock_interruptible(p) p->lock_ops->lock_interruptible(p)
+#define genpd_unlock(p) p->lock_ops->unlock(p)
+
+#define genpd_status_on(genpd) (genpd->status == GPD_STATE_ACTIVE)
+#define genpd_is_irq_safe(genpd) (genpd->flags & GENPD_FLAG_IRQ_SAFE)
+#define genpd_is_always_on(genpd) (genpd->flags & GENPD_FLAG_ALWAYS_ON)
+#define genpd_is_active_wakeup(genpd) (genpd->flags & GENPD_FLAG_ACTIVE_WAKEUP)
+
+static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev,
+ const struct generic_pm_domain *genpd)
+{
+ bool ret;
+
+ ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd);
+
+ /*
+ * Warn once if an IRQ safe device is attached to a no sleep domain, as
+ * to indicate a suboptimal configuration for PM. For an always on
+ * domain this isn't case, thus don't warn.
+ */
+ if (ret && !genpd_is_always_on(genpd))
+ dev_warn_once(dev, "PM domain %s will not be powered off\n",
+ genpd->name);
+
+ return ret;
+}
+
+/*
+ * 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.
+ */
+static struct generic_pm_domain *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)
+{
+ if (IS_ERR_OR_NULL(dev->pm_domain))
+ return ERR_PTR(-EINVAL);
+
+ return pd_to_genpd(dev->pm_domain);
+}
+
+static int genpd_stop_dev(const struct generic_pm_domain *genpd,
+ struct device *dev)
+{
+ return GENPD_DEV_CALLBACK(genpd, int, stop, dev);
+}
+
+static int genpd_start_dev(const struct generic_pm_domain *genpd,
+ struct device *dev)
+{
+ return GENPD_DEV_CALLBACK(genpd, int, start, dev);
+}
+
+static bool genpd_sd_counter_dec(struct generic_pm_domain *genpd)
+{
+ 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);
+ smp_mb__after_atomic();
+}
+
+#ifdef CONFIG_DEBUG_FS
+static void genpd_update_accounting(struct generic_pm_domain *genpd)
+{
+ ktime_t delta, now;
+
+ now = ktime_get();
+ delta = ktime_sub(now, genpd->accounting_time);
+
+ /*
+ * If genpd->status is active, it means we are just
+ * out of off and so update the idle time and vice
+ * versa.
+ */
+ if (genpd->status == GPD_STATE_ACTIVE) {
+ int state_idx = genpd->state_idx;
+
+ genpd->states[state_idx].idle_time =
+ ktime_add(genpd->states[state_idx].idle_time, delta);
+ } else {
+ genpd->on_time = ktime_add(genpd->on_time, delta);
+ }
+
+ genpd->accounting_time = now;
+}
+#else
+static inline void genpd_update_accounting(struct generic_pm_domain *genpd) {}
+#endif
+
+/**
+ * dev_pm_genpd_set_performance_state- Set performance state of device's power
+ * domain.
+ *
+ * @dev: Device for which the performance-state needs to be set.
+ * @state: Target performance state of the device. This can be set as 0 when the
+ * device doesn't have any performance state constraints left (And so
+ * the device wouldn't participate anymore to find the target
+ * performance state of the genpd).
+ *
+ * It is assumed that the users guarantee that the genpd wouldn't be detached
+ * while this routine is getting called.
+ *
+ * Returns 0 on success and negative error values on failures.
+ */
+int dev_pm_genpd_set_performance_state(struct device *dev, unsigned int state)
+{
+ struct generic_pm_domain *genpd;
+ struct generic_pm_domain_data *gpd_data, *pd_data;
+ struct pm_domain_data *pdd;
+ unsigned int prev;
+ int ret = 0;
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -ENODEV;
+
+ if (unlikely(!genpd->set_performance_state))
+ return -EINVAL;
+
+ if (unlikely(!dev->power.subsys_data ||
+ !dev->power.subsys_data->domain_data)) {
+ WARN_ON(1);
+ return -EINVAL;
+ }
+
+ genpd_lock(genpd);
+
+ gpd_data = to_gpd_data(dev->power.subsys_data->domain_data);
+ prev = gpd_data->performance_state;
+ gpd_data->performance_state = state;
+
+ /* New requested state is same as Max requested state */
+ if (state == genpd->performance_state)
+ goto unlock;
+
+ /* New requested state is higher than Max requested state */
+ if (state > genpd->performance_state)
+ goto update_state;
+
+ /* Traverse all devices within the domain */
+ list_for_each_entry(pdd, &genpd->dev_list, list_node) {
+ pd_data = to_gpd_data(pdd);
+
+ if (pd_data->performance_state > state)
+ state = pd_data->performance_state;
+ }
+
+ if (state == genpd->performance_state)
+ goto unlock;
+
+ /*
+ * We aren't propagating performance state changes of a subdomain to its
+ * masters as we don't have hardware that needs it. Over that, the
+ * performance states of subdomain and its masters may not have
+ * one-to-one mapping and would require additional information. We can
+ * get back to this once we have hardware that needs it. For that
+ * reason, we don't have to consider performance state of the subdomains
+ * of genpd here.
+ */
+
+update_state:
+ if (genpd_status_on(genpd)) {
+ ret = genpd->set_performance_state(genpd, state);
+ if (ret) {
+ gpd_data->performance_state = prev;
+ goto unlock;
+ }
+ }
+
+ genpd->performance_state = state;
+
+unlock:
+ genpd_unlock(genpd);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_genpd_set_performance_state);
+
+static int _genpd_power_on(struct generic_pm_domain *genpd, bool timed)
+{
+ unsigned int state_idx = genpd->state_idx;
+ ktime_t time_start;
+ s64 elapsed_ns;
+ int ret;
+
+ if (!genpd->power_on)
+ return 0;
+
+ if (!timed)
+ return genpd->power_on(genpd);
+
+ 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 (unlikely(genpd->set_performance_state)) {
+ ret = genpd->set_performance_state(genpd, genpd->performance_state);
+ if (ret) {
+ pr_warn("%s: Failed to set performance state %d (%d)\n",
+ genpd->name, genpd->performance_state, ret);
+ }
+ }
+
+ if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns)
+ return ret;
+
+ genpd->states[state_idx].power_on_latency_ns = elapsed_ns;
+ genpd->max_off_time_changed = true;
+ pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
+ genpd->name, "on", elapsed_ns);
+
+ return ret;
+}
+
+static int _genpd_power_off(struct generic_pm_domain *genpd, bool timed)
+{
+ unsigned int state_idx = genpd->state_idx;
+ ktime_t time_start;
+ s64 elapsed_ns;
+ int ret;
+
+ if (!genpd->power_off)
+ return 0;
+
+ if (!timed)
+ return genpd->power_off(genpd);
+
+ 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->states[state_idx].power_off_latency_ns)
+ return ret;
+
+ genpd->states[state_idx].power_off_latency_ns = elapsed_ns;
+ genpd->max_off_time_changed = true;
+ pr_debug("%s: Power-%s latency exceeded, new value %lld ns\n",
+ genpd->name, "off", elapsed_ns);
+
+ return ret;
+}
+
+/**
+ * genpd_queue_power_off_work - Queue up the execution of genpd_power_off().
+ * @genpd: PM domain to power off.
+ *
+ * Queue up the execution of genpd_power_off() unless it's already been done
+ * before.
+ */
+static void genpd_queue_power_off_work(struct generic_pm_domain *genpd)
+{
+ queue_work(pm_wq, &genpd->power_off_work);
+}
+
+/**
+ * genpd_power_off - Remove power from a given PM domain.
+ * @genpd: PM domain to power down.
+ * @one_dev_on: If invoked from genpd's ->runtime_suspend|resume() callback, the
+ * RPM status of the releated device is in an intermediate state, not yet turned
+ * into RPM_SUSPENDED. This means genpd_power_off() must allow one device to not
+ * be RPM_SUSPENDED, while it tries to power off the PM domain.
+ *
+ * If all of the @genpd's devices have been suspended and all of its subdomains
+ * have been powered down, remove power from @genpd.
+ */
+static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on,
+ unsigned int depth)
+{
+ struct pm_domain_data *pdd;
+ struct gpd_link *link;
+ unsigned int not_suspended = 0;
+
+ /*
+ * Do not try to power off the domain in the following situations:
+ * (1) The domain is already in the "power off" state.
+ * (2) System suspend is in progress.
+ */
+ if (!genpd_status_on(genpd) || genpd->prepared_count > 0)
+ return 0;
+
+ /*
+ * Abort power off for the PM domain in the following situations:
+ * (1) The domain is configured as always on.
+ * (2) When the domain has a subdomain being powered on.
+ */
+ if (genpd_is_always_on(genpd) || atomic_read(&genpd->sd_count) > 0)
+ return -EBUSY;
+
+ 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);
+ if (stat > PM_QOS_FLAGS_NONE)
+ return -EBUSY;
+
+ /*
+ * Do not allow PM domain to be powered off, when an IRQ safe
+ * device is part of a non-IRQ safe domain.
+ */
+ if (!pm_runtime_suspended(pdd->dev) ||
+ irq_safe_dev_in_no_sleep_domain(pdd->dev, genpd))
+ not_suspended++;
+ }
+
+ if (not_suspended > 1 || (not_suspended == 1 && !one_dev_on))
+ return -EBUSY;
+
+ if (genpd->gov && genpd->gov->power_down_ok) {
+ if (!genpd->gov->power_down_ok(&genpd->domain))
+ return -EAGAIN;
+ }
+
+ /* Default to shallowest state. */
+ if (!genpd->gov)
+ genpd->state_idx = 0;
+
+ if (genpd->power_off) {
+ int ret;
+
+ if (atomic_read(&genpd->sd_count) > 0)
+ return -EBUSY;
+
+ /*
+ * If sd_count > 0 at this point, one of the subdomains hasn't
+ * managed to call genpd_power_on() for the master yet after
+ * incrementing it. In that case genpd_power_on() will wait
+ * for us to drop the lock, so we can call .power_off() and let
+ * the genpd_power_on() restore power for us (this shouldn't
+ * happen very often).
+ */
+ ret = _genpd_power_off(genpd, true);
+ if (ret)
+ return ret;
+ }
+
+ genpd->status = GPD_STATE_POWER_OFF;
+ genpd_update_accounting(genpd);
+
+ list_for_each_entry(link, &genpd->slave_links, slave_node) {
+ genpd_sd_counter_dec(link->master);
+ genpd_lock_nested(link->master, depth + 1);
+ genpd_power_off(link->master, false, depth + 1);
+ genpd_unlock(link->master);
+ }
+
+ return 0;
+}
+
+/**
+ * genpd_power_on - Restore power to a given PM domain and its masters.
+ * @genpd: PM domain to power up.
+ * @depth: nesting count for lockdep.
+ *
+ * Restore power to @genpd and all of its masters so that it is possible to
+ * resume a device belonging to it.
+ */
+static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth)
+{
+ struct gpd_link *link;
+ int ret = 0;
+
+ if (genpd_status_on(genpd))
+ return 0;
+
+ /*
+ * 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) {
+ struct generic_pm_domain *master = link->master;
+
+ genpd_sd_counter_inc(master);
+
+ genpd_lock_nested(master, depth + 1);
+ ret = genpd_power_on(master, depth + 1);
+ genpd_unlock(master);
+
+ if (ret) {
+ genpd_sd_counter_dec(master);
+ goto err;
+ }
+ }
+
+ ret = _genpd_power_on(genpd, true);
+ if (ret)
+ goto err;
+
+ genpd->status = GPD_STATE_ACTIVE;
+ genpd_update_accounting(genpd);
+
+ return 0;
+
+ err:
+ list_for_each_entry_continue_reverse(link,
+ &genpd->slave_links,
+ slave_node) {
+ genpd_sd_counter_dec(link->master);
+ genpd_lock_nested(link->master, depth + 1);
+ genpd_power_off(link->master, false, depth + 1);
+ genpd_unlock(link->master);
+ }
+
+ return ret;
+}
+
+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;
+ if (pdd) {
+ 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)) {
+ genpd_lock(genpd);
+ genpd->max_off_time_changed = true;
+ genpd_unlock(genpd);
+ }
+
+ dev = dev->parent;
+ if (!dev || dev->power.ignore_children)
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+/**
+ * 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);
+
+ genpd_lock(genpd);
+ genpd_power_off(genpd, false, 0);
+ genpd_unlock(genpd);
+}
+
+/**
+ * __genpd_runtime_suspend - walk the hierarchy of ->runtime_suspend() callbacks
+ * @dev: Device to handle.
+ */
+static int __genpd_runtime_suspend(struct device *dev)
+{
+ int (*cb)(struct device *__dev);
+
+ 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;
+
+ if (!cb && dev->driver && dev->driver->pm)
+ cb = dev->driver->pm->runtime_suspend;
+
+ return cb ? cb(dev) : 0;
+}
+
+/**
+ * __genpd_runtime_resume - walk the hierarchy of ->runtime_resume() callbacks
+ * @dev: Device to handle.
+ */
+static int __genpd_runtime_resume(struct device *dev)
+{
+ int (*cb)(struct device *__dev);
+
+ 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;
+
+ if (!cb && dev->driver && dev->driver->pm)
+ cb = dev->driver->pm->runtime_resume;
+
+ return cb ? cb(dev) : 0;
+}
+
+/**
+ * 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 genpd_runtime_suspend(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ bool (*suspend_ok)(struct device *__dev);
+ struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+ bool runtime_pm = pm_runtime_enabled(dev);
+ ktime_t time_start;
+ s64 elapsed_ns;
+ int ret;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ /*
+ * A runtime PM centric subsystem/driver may re-use the runtime PM
+ * callbacks for other purposes than runtime PM. In those scenarios
+ * runtime PM is disabled. Under these circumstances, we shall skip
+ * validating/measuring the PM QoS latency.
+ */
+ suspend_ok = genpd->gov ? genpd->gov->suspend_ok : NULL;
+ if (runtime_pm && suspend_ok && !suspend_ok(dev))
+ return -EBUSY;
+
+ /* Measure suspend latency. */
+ time_start = 0;
+ if (runtime_pm)
+ time_start = ktime_get();
+
+ ret = __genpd_runtime_suspend(dev);
+ if (ret)
+ return ret;
+
+ ret = genpd_stop_dev(genpd, dev);
+ if (ret) {
+ __genpd_runtime_resume(dev);
+ return ret;
+ }
+
+ /* Update suspend latency value if the measured time exceeds it. */
+ if (runtime_pm) {
+ elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+ if (elapsed_ns > td->suspend_latency_ns) {
+ td->suspend_latency_ns = elapsed_ns;
+ dev_dbg(dev, "suspend latency exceeded, %lld ns\n",
+ elapsed_ns);
+ genpd->max_off_time_changed = true;
+ td->constraint_changed = true;
+ }
+ }
+
+ /*
+ * If power.irq_safe is set, this routine may be run with
+ * IRQs disabled, so suspend only if the PM domain also is irq_safe.
+ */
+ if (irq_safe_dev_in_no_sleep_domain(dev, genpd))
+ return 0;
+
+ genpd_lock(genpd);
+ genpd_power_off(genpd, true, 0);
+ genpd_unlock(genpd);
+
+ return 0;
+}
+
+/**
+ * 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 genpd_runtime_resume(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ struct gpd_timing_data *td = &dev_gpd_data(dev)->td;
+ bool runtime_pm = pm_runtime_enabled(dev);
+ ktime_t time_start;
+ s64 elapsed_ns;
+ int ret;
+ bool timed = true;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ /*
+ * As we don't power off a non IRQ safe domain, which holds
+ * an IRQ safe device, we don't need to restore power to it.
+ */
+ if (irq_safe_dev_in_no_sleep_domain(dev, genpd)) {
+ timed = false;
+ goto out;
+ }
+
+ genpd_lock(genpd);
+ ret = genpd_power_on(genpd, 0);
+ genpd_unlock(genpd);
+
+ if (ret)
+ return ret;
+
+ out:
+ /* Measure resume latency. */
+ time_start = 0;
+ if (timed && runtime_pm)
+ time_start = ktime_get();
+
+ ret = genpd_start_dev(genpd, dev);
+ if (ret)
+ goto err_poweroff;
+
+ ret = __genpd_runtime_resume(dev);
+ if (ret)
+ goto err_stop;
+
+ /* Update resume latency value if the measured time exceeds it. */
+ if (timed && runtime_pm) {
+ elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start));
+ if (elapsed_ns > td->resume_latency_ns) {
+ td->resume_latency_ns = elapsed_ns;
+ dev_dbg(dev, "resume latency exceeded, %lld ns\n",
+ elapsed_ns);
+ genpd->max_off_time_changed = true;
+ td->constraint_changed = true;
+ }
+ }
+
+ return 0;
+
+err_stop:
+ genpd_stop_dev(genpd, dev);
+err_poweroff:
+ if (!pm_runtime_is_irq_safe(dev) ||
+ (pm_runtime_is_irq_safe(dev) && genpd_is_irq_safe(genpd))) {
+ genpd_lock(genpd);
+ genpd_power_off(genpd, true, 0);
+ genpd_unlock(genpd);
+ }
+
+ return ret;
+}
+
+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);
+
+/**
+ * genpd_power_off_unused - Power off all PM domains with no devices in use.
+ */
+static int __init genpd_power_off_unused(void)
+{
+ struct generic_pm_domain *genpd;
+
+ if (pd_ignore_unused) {
+ pr_warn("genpd: Not disabling unused power domains\n");
+ return 0;
+ }
+
+ 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);
+
+ return 0;
+}
+late_initcall(genpd_power_off_unused);
+
+#if defined(CONFIG_PM_SLEEP) || defined(CONFIG_PM_GENERIC_DOMAINS_OF)
+
+static bool genpd_present(const struct generic_pm_domain *genpd)
+{
+ const struct generic_pm_domain *gpd;
+
+ 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;
+}
+
+#endif
+
+#ifdef CONFIG_PM_SLEEP
+
+/**
+ * genpd_sync_power_off - Synchronously power off a PM domain and its masters.
+ * @genpd: PM domain to power off, if possible.
+ * @use_lock: use the lock.
+ * @depth: nesting count for lockdep.
+ *
+ * Check if the given PM domain can be powered off (during system suspend or
+ * hibernation) and do that if so. Also, in that case propagate to its masters.
+ *
+ * This function is only called in "noirq" and "syscore" stages of system power
+ * transitions. The "noirq" callbacks may be executed asynchronously, thus in
+ * these cases the lock must be held.
+ */
+static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock,
+ unsigned int depth)
+{
+ struct gpd_link *link;
+
+ if (!genpd_status_on(genpd) || genpd_is_always_on(genpd))
+ return;
+
+ if (genpd->suspended_count != genpd->device_count
+ || atomic_read(&genpd->sd_count) > 0)
+ return;
+
+ /* Choose the deepest state when suspending */
+ genpd->state_idx = genpd->state_count - 1;
+ if (_genpd_power_off(genpd, false))
+ return;
+
+ genpd->status = GPD_STATE_POWER_OFF;
+
+ list_for_each_entry(link, &genpd->slave_links, slave_node) {
+ genpd_sd_counter_dec(link->master);
+
+ if (use_lock)
+ genpd_lock_nested(link->master, depth + 1);
+
+ genpd_sync_power_off(link->master, use_lock, depth + 1);
+
+ if (use_lock)
+ genpd_unlock(link->master);
+ }
+}
+
+/**
+ * genpd_sync_power_on - Synchronously power on a PM domain and its masters.
+ * @genpd: PM domain to power on.
+ * @use_lock: use the lock.
+ * @depth: nesting count for lockdep.
+ *
+ * This function is only called in "noirq" and "syscore" stages of system power
+ * transitions. The "noirq" callbacks may be executed asynchronously, thus in
+ * these cases the lock must be held.
+ */
+static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock,
+ unsigned int depth)
+{
+ struct gpd_link *link;
+
+ if (genpd_status_on(genpd))
+ return;
+
+ list_for_each_entry(link, &genpd->slave_links, slave_node) {
+ genpd_sd_counter_inc(link->master);
+
+ if (use_lock)
+ genpd_lock_nested(link->master, depth + 1);
+
+ genpd_sync_power_on(link->master, use_lock, depth + 1);
+
+ if (use_lock)
+ genpd_unlock(link->master);
+ }
+
+ _genpd_power_on(genpd, false);
+
+ genpd->status = GPD_STATE_ACTIVE;
+}
+
+/**
+ * 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 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,
+ const struct generic_pm_domain *genpd)
+{
+ bool active_wakeup;
+
+ if (!device_can_wakeup(dev))
+ return false;
+
+ active_wakeup = genpd_is_active_wakeup(genpd);
+ return device_may_wakeup(dev) ? active_wakeup : !active_wakeup;
+}
+
+/**
+ * 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 genpd_prepare(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ int ret;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ /*
+ * 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.
+ */
+ if (resume_needed(dev, genpd))
+ pm_runtime_resume(dev);
+
+ genpd_lock(genpd);
+
+ if (genpd->prepared_count++ == 0)
+ genpd->suspended_count = 0;
+
+ genpd_unlock(genpd);
+
+ ret = pm_generic_prepare(dev);
+ if (ret < 0) {
+ genpd_lock(genpd);
+
+ genpd->prepared_count--;
+
+ genpd_unlock(genpd);
+ }
+
+ /* Never return 1, as genpd don't cope with the direct_complete path. */
+ return ret >= 0 ? 0 : ret;
+}
+
+/**
+ * genpd_finish_suspend - Completion of suspend or hibernation of device in an
+ * I/O pm domain.
+ * @dev: Device to suspend.
+ * @poweroff: Specifies if this is a poweroff_noirq or suspend_noirq callback.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int genpd_finish_suspend(struct device *dev, bool poweroff)
+{
+ struct generic_pm_domain *genpd;
+ int ret = 0;
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ if (poweroff)
+ ret = pm_generic_poweroff_noirq(dev);
+ else
+ ret = pm_generic_suspend_noirq(dev);
+ if (ret)
+ return ret;
+
+ if (dev->power.wakeup_path && genpd_is_active_wakeup(genpd))
+ return 0;
+
+ if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+ !pm_runtime_status_suspended(dev)) {
+ ret = genpd_stop_dev(genpd, dev);
+ if (ret) {
+ if (poweroff)
+ pm_generic_restore_noirq(dev);
+ else
+ pm_generic_resume_noirq(dev);
+ return ret;
+ }
+ }
+
+ genpd_lock(genpd);
+ genpd->suspended_count++;
+ genpd_sync_power_off(genpd, true, 0);
+ genpd_unlock(genpd);
+
+ return 0;
+}
+
+/**
+ * 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 genpd_suspend_noirq(struct device *dev)
+{
+ dev_dbg(dev, "%s()\n", __func__);
+
+ return genpd_finish_suspend(dev, false);
+}
+
+/**
+ * genpd_resume_noirq - Start of resume of device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * Restore power to the device's PM domain, if necessary, and start the device.
+ */
+static int genpd_resume_noirq(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ int ret;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ if (dev->power.wakeup_path && genpd_is_active_wakeup(genpd))
+ return pm_generic_resume_noirq(dev);
+
+ genpd_lock(genpd);
+ genpd_sync_power_on(genpd, true, 0);
+ genpd->suspended_count--;
+ genpd_unlock(genpd);
+
+ if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+ !pm_runtime_status_suspended(dev)) {
+ ret = genpd_start_dev(genpd, dev);
+ if (ret)
+ return ret;
+ }
+
+ return pm_generic_resume_noirq(dev);
+}
+
+/**
+ * genpd_freeze_noirq - Completion of freezing 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 genpd_freeze_noirq(struct device *dev)
+{
+ const struct generic_pm_domain *genpd;
+ int ret = 0;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ ret = pm_generic_freeze_noirq(dev);
+ if (ret)
+ return ret;
+
+ if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+ !pm_runtime_status_suspended(dev))
+ ret = genpd_stop_dev(genpd, dev);
+
+ return ret;
+}
+
+/**
+ * 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 genpd_thaw_noirq(struct device *dev)
+{
+ const struct generic_pm_domain *genpd;
+ int ret = 0;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+ !pm_runtime_status_suspended(dev)) {
+ ret = genpd_start_dev(genpd, dev);
+ if (ret)
+ return ret;
+ }
+
+ return pm_generic_thaw_noirq(dev);
+}
+
+/**
+ * genpd_poweroff_noirq - Completion of hibernation of device in an
+ * I/O PM domain.
+ * @dev: Device to poweroff.
+ *
+ * Stop the device and remove power from the domain if all devices in it have
+ * been stopped.
+ */
+static int genpd_poweroff_noirq(struct device *dev)
+{
+ dev_dbg(dev, "%s()\n", __func__);
+
+ return genpd_finish_suspend(dev, true);
+}
+
+/**
+ * genpd_restore_noirq - Start of restore of device in an I/O PM domain.
+ * @dev: Device to resume.
+ *
+ * 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.
+ */
+static int genpd_restore_noirq(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ int ret = 0;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return -EINVAL;
+
+ /*
+ * At this point suspended_count == 0 means we are being run for the
+ * first time for the given domain in the present cycle.
+ */
+ genpd_lock(genpd);
+ if (genpd->suspended_count++ == 0)
+ /*
+ * The boot kernel might put the domain into arbitrary state,
+ * so make it appear as powered off to genpd_sync_power_on(),
+ * so that it tries to power it on in case it was really off.
+ */
+ genpd->status = GPD_STATE_POWER_OFF;
+
+ genpd_sync_power_on(genpd, true, 0);
+ genpd_unlock(genpd);
+
+ if (genpd->dev_ops.stop && genpd->dev_ops.start &&
+ !pm_runtime_status_suspended(dev)) {
+ ret = genpd_start_dev(genpd, dev);
+ if (ret)
+ return ret;
+ }
+
+ return pm_generic_restore_noirq(dev);
+}
+
+/**
+ * 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 genpd_complete(struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return;
+
+ pm_generic_complete(dev);
+
+ genpd_lock(genpd);
+
+ genpd->prepared_count--;
+ if (!genpd->prepared_count)
+ genpd_queue_power_off_work(genpd);
+
+ genpd_unlock(genpd);
+}
+
+/**
+ * genpd_syscore_switch - Switch power during system core suspend or resume.
+ * @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.
+ */
+static void genpd_syscore_switch(struct device *dev, bool suspend)
+{
+ struct generic_pm_domain *genpd;
+
+ genpd = dev_to_genpd(dev);
+ if (!genpd_present(genpd))
+ return;
+
+ if (suspend) {
+ genpd->suspended_count++;
+ genpd_sync_power_off(genpd, false, 0);
+ } else {
+ genpd_sync_power_on(genpd, false, 0);
+ genpd->suspended_count--;
+ }
+}
+
+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);
+
+#else /* !CONFIG_PM_SLEEP */
+
+#define genpd_prepare NULL
+#define genpd_suspend_noirq NULL
+#define genpd_resume_noirq NULL
+#define genpd_freeze_noirq NULL
+#define genpd_thaw_noirq NULL
+#define genpd_poweroff_noirq NULL
+#define genpd_restore_noirq NULL
+#define genpd_complete NULL
+
+#endif /* CONFIG_PM_SLEEP */
+
+static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev,
+ struct gpd_timing_data *td)
+{
+ struct generic_pm_domain_data *gpd_data;
+ int ret;
+
+ ret = dev_pm_get_subsys_data(dev);
+ if (ret)
+ return ERR_PTR(ret);
+
+ gpd_data = kzalloc(sizeof(*gpd_data), GFP_KERNEL);
+ if (!gpd_data) {
+ ret = -ENOMEM;
+ goto err_put;
+ }
+
+ if (td)
+ gpd_data->td = *td;
+
+ gpd_data->base.dev = dev;
+ gpd_data->td.constraint_changed = true;
+ gpd_data->td.effective_constraint_ns = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT_NS;
+ 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;
+
+ spin_unlock_irq(&dev->power.lock);
+
+ return gpd_data;
+
+ err_free:
+ spin_unlock_irq(&dev->power.lock);
+ kfree(gpd_data);
+ err_put:
+ dev_pm_put_subsys_data(dev);
+ return ERR_PTR(ret);
+}
+
+static void genpd_free_dev_data(struct device *dev,
+ struct generic_pm_domain_data *gpd_data)
+{
+ spin_lock_irq(&dev->power.lock);
+
+ dev->power.subsys_data->domain_data = NULL;
+
+ spin_unlock_irq(&dev->power.lock);
+
+ kfree(gpd_data);
+ dev_pm_put_subsys_data(dev);
+}
+
+static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev,
+ struct gpd_timing_data *td)
+{
+ struct generic_pm_domain_data *gpd_data;
+ int ret;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(dev))
+ return -EINVAL;
+
+ gpd_data = genpd_alloc_dev_data(dev, td);
+ if (IS_ERR(gpd_data))
+ return PTR_ERR(gpd_data);
+
+ ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0;
+ if (ret)
+ goto out;
+
+ genpd_lock(genpd);
+
+ dev_pm_domain_set(dev, &genpd->domain);
+
+ genpd->device_count++;
+ genpd->max_off_time_changed = true;
+
+ list_add_tail(&gpd_data->base.list_node, &genpd->dev_list);
+
+ genpd_unlock(genpd);
+ out:
+ if (ret)
+ genpd_free_dev_data(dev, gpd_data);
+ else
+ dev_pm_qos_add_notifier(dev, &gpd_data->nb);
+
+ return ret;
+}
+
+/**
+ * pm_genpd_add_device - Add a device to an I/O PM domain.
+ * @genpd: PM domain to add the device to.
+ * @dev: Device to be added.
+ */
+int pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev)
+{
+ int ret;
+
+ mutex_lock(&gpd_list_lock);
+ ret = genpd_add_device(genpd, dev, NULL);
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_add_device);
+
+static int genpd_remove_device(struct generic_pm_domain *genpd,
+ struct device *dev)
+{
+ struct generic_pm_domain_data *gpd_data;
+ struct pm_domain_data *pdd;
+ int ret = 0;
+
+ dev_dbg(dev, "%s()\n", __func__);
+
+ pdd = dev->power.subsys_data->domain_data;
+ gpd_data = to_gpd_data(pdd);
+ dev_pm_qos_remove_notifier(dev, &gpd_data->nb);
+
+ genpd_lock(genpd);
+
+ if (genpd->prepared_count > 0) {
+ ret = -EAGAIN;
+ goto out;
+ }
+
+ genpd->device_count--;
+ genpd->max_off_time_changed = true;
+
+ dev_pm_domain_set(dev, NULL);
+
+ list_del_init(&pdd->list_node);
+
+ genpd_unlock(genpd);
+
+ if (genpd->detach_dev)
+ genpd->detach_dev(genpd, dev);
+
+ genpd_free_dev_data(dev, gpd_data);
+
+ return 0;
+
+ out:
+ genpd_unlock(genpd);
+ dev_pm_qos_add_notifier(dev, &gpd_data->nb);
+
+ return ret;
+}
+
+/**
+ * pm_genpd_remove_device - Remove a device from an I/O PM domain.
+ * @dev: Device to be removed.
+ */
+int pm_genpd_remove_device(struct device *dev)
+{
+ struct generic_pm_domain *genpd = genpd_lookup_dev(dev);
+
+ if (!genpd)
+ return -EINVAL;
+
+ return genpd_remove_device(genpd, dev);
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove_device);
+
+static int genpd_add_subdomain(struct generic_pm_domain *genpd,
+ struct generic_pm_domain *subdomain)
+{
+ struct gpd_link *link, *itr;
+ int ret = 0;
+
+ if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain)
+ || genpd == subdomain)
+ return -EINVAL;
+
+ /*
+ * If the domain can be powered on/off in an IRQ safe
+ * context, ensure that the subdomain can also be
+ * powered on/off in that context.
+ */
+ if (!genpd_is_irq_safe(genpd) && genpd_is_irq_safe(subdomain)) {
+ WARN(1, "Parent %s of subdomain %s must be IRQ safe\n",
+ genpd->name, subdomain->name);
+ return -EINVAL;
+ }
+
+ link = kzalloc(sizeof(*link), GFP_KERNEL);
+ if (!link)
+ return -ENOMEM;
+
+ genpd_lock(subdomain);
+ genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
+
+ if (!genpd_status_on(genpd) && genpd_status_on(subdomain)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ list_for_each_entry(itr, &genpd->master_links, master_node) {
+ if (itr->slave == subdomain && itr->master == genpd) {
+ ret = -EINVAL;
+ goto out;
+ }
+ }
+
+ link->master = genpd;
+ list_add_tail(&link->master_node, &genpd->master_links);
+ link->slave = subdomain;
+ list_add_tail(&link->slave_node, &subdomain->slave_links);
+ if (genpd_status_on(subdomain))
+ genpd_sd_counter_inc(genpd);
+
+ out:
+ genpd_unlock(genpd);
+ genpd_unlock(subdomain);
+ if (ret)
+ kfree(link);
+ return ret;
+}
+
+/**
+ * pm_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
+ * @genpd: Master PM domain to add the subdomain to.
+ * @subdomain: Subdomain to be added.
+ */
+int pm_genpd_add_subdomain(struct generic_pm_domain *genpd,
+ struct generic_pm_domain *subdomain)
+{
+ int ret;
+
+ mutex_lock(&gpd_list_lock);
+ ret = genpd_add_subdomain(genpd, subdomain);
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_add_subdomain);
+
+/**
+ * pm_genpd_remove_subdomain - Remove a subdomain from an I/O PM domain.
+ * @genpd: Master PM domain to remove the subdomain from.
+ * @subdomain: Subdomain to be removed.
+ */
+int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
+ struct generic_pm_domain *subdomain)
+{
+ struct gpd_link *l, *link;
+ int ret = -EINVAL;
+
+ if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
+ return -EINVAL;
+
+ genpd_lock(subdomain);
+ genpd_lock_nested(genpd, SINGLE_DEPTH_NESTING);
+
+ if (!list_empty(&subdomain->master_links) || subdomain->device_count) {
+ pr_warn("%s: unable to remove subdomain %s\n", genpd->name,
+ subdomain->name);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ list_for_each_entry_safe(link, l, &genpd->master_links, master_node) {
+ if (link->slave != subdomain)
+ continue;
+
+ list_del(&link->master_node);
+ list_del(&link->slave_node);
+ kfree(link);
+ if (genpd_status_on(subdomain))
+ genpd_sd_counter_dec(genpd);
+
+ ret = 0;
+ break;
+ }
+
+out:
+ genpd_unlock(genpd);
+ genpd_unlock(subdomain);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove_subdomain);
+
+static int genpd_set_default_power_state(struct generic_pm_domain *genpd)
+{
+ struct genpd_power_state *state;
+
+ state = kzalloc(sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return -ENOMEM;
+
+ genpd->states = state;
+ genpd->state_count = 1;
+ genpd->free = state;
+
+ return 0;
+}
+
+static void genpd_lock_init(struct generic_pm_domain *genpd)
+{
+ if (genpd->flags & GENPD_FLAG_IRQ_SAFE) {
+ spin_lock_init(&genpd->slock);
+ genpd->lock_ops = &genpd_spin_ops;
+ } else {
+ mutex_init(&genpd->mlock);
+ genpd->lock_ops = &genpd_mtx_ops;
+ }
+}
+
+/**
+ * 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.
+ *
+ * Returns 0 on successful initialization, else a negative error code.
+ */
+int pm_genpd_init(struct generic_pm_domain *genpd,
+ struct dev_power_governor *gov, bool is_off)
+{
+ int ret;
+
+ if (IS_ERR_OR_NULL(genpd))
+ return -EINVAL;
+
+ INIT_LIST_HEAD(&genpd->master_links);
+ INIT_LIST_HEAD(&genpd->slave_links);
+ INIT_LIST_HEAD(&genpd->dev_list);
+ genpd_lock_init(genpd);
+ genpd->gov = gov;
+ INIT_WORK(&genpd->power_off_work, genpd_power_off_work_fn);
+ atomic_set(&genpd->sd_count, 0);
+ genpd->status = is_off ? GPD_STATE_POWER_OFF : GPD_STATE_ACTIVE;
+ genpd->device_count = 0;
+ genpd->max_off_time_ns = -1;
+ genpd->max_off_time_changed = true;
+ genpd->provider = NULL;
+ genpd->has_provider = false;
+ genpd->accounting_time = ktime_get();
+ genpd->domain.ops.runtime_suspend = genpd_runtime_suspend;
+ genpd->domain.ops.runtime_resume = genpd_runtime_resume;
+ genpd->domain.ops.prepare = genpd_prepare;
+ genpd->domain.ops.suspend_noirq = genpd_suspend_noirq;
+ genpd->domain.ops.resume_noirq = genpd_resume_noirq;
+ genpd->domain.ops.freeze_noirq = genpd_freeze_noirq;
+ genpd->domain.ops.thaw_noirq = genpd_thaw_noirq;
+ genpd->domain.ops.poweroff_noirq = genpd_poweroff_noirq;
+ genpd->domain.ops.restore_noirq = genpd_restore_noirq;
+ genpd->domain.ops.complete = genpd_complete;
+
+ if (genpd->flags & GENPD_FLAG_PM_CLK) {
+ genpd->dev_ops.stop = pm_clk_suspend;
+ genpd->dev_ops.start = pm_clk_resume;
+ }
+
+ /* Always-on domains must be powered on at initialization. */
+ if (genpd_is_always_on(genpd) && !genpd_status_on(genpd))
+ return -EINVAL;
+
+ /* Use only one "off" state if there were no states declared */
+ if (genpd->state_count == 0) {
+ ret = genpd_set_default_power_state(genpd);
+ if (ret)
+ return ret;
+ } else if (!gov) {
+ pr_warn("%s : no governor for states\n", genpd->name);
+ }
+
+ device_initialize(&genpd->dev);
+ dev_set_name(&genpd->dev, "%s", genpd->name);
+
+ mutex_lock(&gpd_list_lock);
+ list_add(&genpd->gpd_list_node, &gpd_list);
+ mutex_unlock(&gpd_list_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_init);
+
+static int genpd_remove(struct generic_pm_domain *genpd)
+{
+ struct gpd_link *l, *link;
+
+ if (IS_ERR_OR_NULL(genpd))
+ return -EINVAL;
+
+ genpd_lock(genpd);
+
+ if (genpd->has_provider) {
+ genpd_unlock(genpd);
+ pr_err("Provider present, unable to remove %s\n", genpd->name);
+ return -EBUSY;
+ }
+
+ if (!list_empty(&genpd->master_links) || genpd->device_count) {
+ genpd_unlock(genpd);
+ pr_err("%s: unable to remove %s\n", __func__, genpd->name);
+ return -EBUSY;
+ }
+
+ list_for_each_entry_safe(link, l, &genpd->slave_links, slave_node) {
+ list_del(&link->master_node);
+ list_del(&link->slave_node);
+ kfree(link);
+ }
+
+ list_del(&genpd->gpd_list_node);
+ genpd_unlock(genpd);
+ cancel_work_sync(&genpd->power_off_work);
+ kfree(genpd->free);
+ pr_debug("%s: removed %s\n", __func__, genpd->name);
+
+ return 0;
+}
+
+/**
+ * pm_genpd_remove - Remove a generic I/O PM domain
+ * @genpd: Pointer to PM domain that is to be removed.
+ *
+ * To remove the PM domain, this function:
+ * - Removes the PM domain as a subdomain to any parent domains,
+ * if it was added.
+ * - Removes the PM domain from the list of registered PM domains.
+ *
+ * The PM domain will only be removed, if the associated provider has
+ * been removed, it is not a parent to any other PM domain and has no
+ * devices associated with it.
+ */
+int pm_genpd_remove(struct generic_pm_domain *genpd)
+{
+ int ret;
+
+ mutex_lock(&gpd_list_lock);
+ ret = genpd_remove(genpd);
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(pm_genpd_remove);
+
+#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:
+ * - genpd_xlate_simple() for 1:1 device tree node to PM domain mapping.
+ * - 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);
+
+/**
+ * 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.
+ */
+static struct generic_pm_domain *genpd_xlate_simple(
+ struct of_phandle_args *genpdspec,
+ void *data)
+{
+ return data;
+}
+
+/**
+ * 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.
+ */
+static struct generic_pm_domain *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];
+}
+
+/**
+ * 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.
+ */
+static int 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 %pOF\n", np);
+
+ return 0;
+}
+
+/**
+ * of_genpd_add_provider_simple() - Register a simple PM domain provider
+ * @np: Device node pointer associated with the PM domain provider.
+ * @genpd: Pointer to PM domain associated with the PM domain provider.
+ */
+int of_genpd_add_provider_simple(struct device_node *np,
+ struct generic_pm_domain *genpd)
+{
+ int ret = -EINVAL;
+
+ if (!np || !genpd)
+ return -EINVAL;
+
+ mutex_lock(&gpd_list_lock);
+
+ if (!genpd_present(genpd))
+ goto unlock;
+
+ genpd->dev.of_node = np;
+
+ /* Parse genpd OPP table */
+ if (genpd->set_performance_state) {
+ ret = dev_pm_opp_of_add_table(&genpd->dev);
+ if (ret) {
+ dev_err(&genpd->dev, "Failed to add OPP table: %d\n",
+ ret);
+ goto unlock;
+ }
+ }
+
+ ret = genpd_add_provider(np, genpd_xlate_simple, genpd);
+ if (ret) {
+ if (genpd->set_performance_state)
+ dev_pm_opp_of_remove_table(&genpd->dev);
+
+ goto unlock;
+ }
+
+ genpd->provider = &np->fwnode;
+ genpd->has_provider = true;
+
+unlock:
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_provider_simple);
+
+/**
+ * of_genpd_add_provider_onecell() - Register a onecell PM domain provider
+ * @np: Device node pointer associated with the PM domain provider.
+ * @data: Pointer to the data associated with the PM domain provider.
+ */
+int of_genpd_add_provider_onecell(struct device_node *np,
+ struct genpd_onecell_data *data)
+{
+ struct generic_pm_domain *genpd;
+ unsigned int i;
+ int ret = -EINVAL;
+
+ if (!np || !data)
+ return -EINVAL;
+
+ mutex_lock(&gpd_list_lock);
+
+ if (!data->xlate)
+ data->xlate = genpd_xlate_onecell;
+
+ for (i = 0; i < data->num_domains; i++) {
+ genpd = data->domains[i];
+
+ if (!genpd)
+ continue;
+ if (!genpd_present(genpd))
+ goto error;
+
+ genpd->dev.of_node = np;
+
+ /* Parse genpd OPP table */
+ if (genpd->set_performance_state) {
+ ret = dev_pm_opp_of_add_table_indexed(&genpd->dev, i);
+ if (ret) {
+ dev_err(&genpd->dev, "Failed to add OPP table for index %d: %d\n",
+ i, ret);
+ goto error;
+ }
+ }
+
+ genpd->provider = &np->fwnode;
+ genpd->has_provider = true;
+ }
+
+ ret = genpd_add_provider(np, data->xlate, data);
+ if (ret < 0)
+ goto error;
+
+ mutex_unlock(&gpd_list_lock);
+
+ return 0;
+
+error:
+ while (i--) {
+ genpd = data->domains[i];
+
+ if (!genpd)
+ continue;
+
+ genpd->provider = NULL;
+ genpd->has_provider = false;
+
+ if (genpd->set_performance_state)
+ dev_pm_opp_of_remove_table(&genpd->dev);
+ }
+
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_provider_onecell);
+
+/**
+ * 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, *tmp;
+ struct generic_pm_domain *gpd;
+
+ mutex_lock(&gpd_list_lock);
+ mutex_lock(&of_genpd_mutex);
+ list_for_each_entry_safe(cp, tmp, &of_genpd_providers, link) {
+ if (cp->node == np) {
+ /*
+ * For each PM domain associated with the
+ * provider, set the 'has_provider' to false
+ * so that the PM domain can be safely removed.
+ */
+ list_for_each_entry(gpd, &gpd_list, gpd_list_node) {
+ if (gpd->provider == &np->fwnode) {
+ gpd->has_provider = false;
+
+ if (!gpd->set_performance_state)
+ continue;
+
+ dev_pm_opp_of_remove_table(&gpd->dev);
+ }
+ }
+
+ list_del(&cp->link);
+ of_node_put(cp->node);
+ kfree(cp);
+ break;
+ }
+ }
+ mutex_unlock(&of_genpd_mutex);
+ mutex_unlock(&gpd_list_lock);
+}
+EXPORT_SYMBOL_GPL(of_genpd_del_provider);
+
+/**
+ * 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.
+ */
+static struct generic_pm_domain *genpd_get_from_provider(
+ struct of_phandle_args *genpdspec)
+{
+ struct generic_pm_domain *genpd = ERR_PTR(-ENOENT);
+ struct of_genpd_provider *provider;
+
+ if (!genpdspec)
+ return ERR_PTR(-EINVAL);
+
+ 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;
+}
+
+/**
+ * of_genpd_add_device() - Add a device to an I/O PM domain
+ * @genpdspec: OF phandle args to use for look-up PM domain
+ * @dev: Device to be added.
+ *
+ * Looks-up an I/O PM domain based upon phandle args provided and adds
+ * the device to the PM domain. Returns a negative error code on failure.
+ */
+int of_genpd_add_device(struct of_phandle_args *genpdspec, struct device *dev)
+{
+ struct generic_pm_domain *genpd;
+ int ret;
+
+ mutex_lock(&gpd_list_lock);
+
+ genpd = genpd_get_from_provider(genpdspec);
+ if (IS_ERR(genpd)) {
+ ret = PTR_ERR(genpd);
+ goto out;
+ }
+
+ ret = genpd_add_device(genpd, dev, NULL);
+
+out:
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_device);
+
+/**
+ * of_genpd_add_subdomain - Add a subdomain to an I/O PM domain.
+ * @parent_spec: OF phandle args to use for parent PM domain look-up
+ * @subdomain_spec: OF phandle args to use for subdomain look-up
+ *
+ * Looks-up a parent PM domain and subdomain based upon phandle args
+ * provided and adds the subdomain to the parent PM domain. Returns a
+ * negative error code on failure.
+ */
+int of_genpd_add_subdomain(struct of_phandle_args *parent_spec,
+ struct of_phandle_args *subdomain_spec)
+{
+ struct generic_pm_domain *parent, *subdomain;
+ int ret;
+
+ mutex_lock(&gpd_list_lock);
+
+ parent = genpd_get_from_provider(parent_spec);
+ if (IS_ERR(parent)) {
+ ret = PTR_ERR(parent);
+ goto out;
+ }
+
+ subdomain = genpd_get_from_provider(subdomain_spec);
+ if (IS_ERR(subdomain)) {
+ ret = PTR_ERR(subdomain);
+ goto out;
+ }
+
+ ret = genpd_add_subdomain(parent, subdomain);
+
+out:
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(of_genpd_add_subdomain);
+
+/**
+ * of_genpd_remove_last - Remove the last PM domain registered for a provider
+ * @provider: Pointer to device structure associated with provider
+ *
+ * Find the last PM domain that was added by a particular provider and
+ * remove this PM domain from the list of PM domains. The provider is
+ * identified by the 'provider' device structure that is passed. The PM
+ * domain will only be removed, if the provider associated with domain
+ * has been removed.
+ *
+ * Returns a valid pointer to struct generic_pm_domain on success or
+ * ERR_PTR() on failure.
+ */
+struct generic_pm_domain *of_genpd_remove_last(struct device_node *np)
+{
+ struct generic_pm_domain *gpd, *tmp, *genpd = ERR_PTR(-ENOENT);
+ int ret;
+
+ if (IS_ERR_OR_NULL(np))
+ return ERR_PTR(-EINVAL);
+
+ mutex_lock(&gpd_list_lock);
+ list_for_each_entry_safe(gpd, tmp, &gpd_list, gpd_list_node) {
+ if (gpd->provider == &np->fwnode) {
+ ret = genpd_remove(gpd);
+ genpd = ret ? ERR_PTR(ret) : gpd;
+ break;
+ }
+ }
+ mutex_unlock(&gpd_list_lock);
+
+ return genpd;
+}
+EXPORT_SYMBOL_GPL(of_genpd_remove_last);
+
+static void genpd_release_dev(struct device *dev)
+{
+ kfree(dev);
+}
+
+static struct bus_type genpd_bus_type = {
+ .name = "genpd",
+};
+
+/**
+ * genpd_dev_pm_detach - Detach a device from its PM domain.
+ * @dev: Device to detach.
+ * @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)
+{
+ struct generic_pm_domain *pd;
+ unsigned int i;
+ int ret = 0;
+
+ pd = dev_to_genpd(dev);
+ if (IS_ERR(pd))
+ return;
+
+ dev_dbg(dev, "removing from PM domain %s\n", pd->name);
+
+ for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) {
+ ret = genpd_remove_device(pd, dev);
+ if (ret != -EAGAIN)
+ break;
+
+ mdelay(i);
+ 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);
+
+ /* Unregister the device if it was created by genpd. */
+ if (dev->bus == &genpd_bus_type)
+ device_unregister(dev);
+}
+
+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);
+}
+
+static int __genpd_dev_pm_attach(struct device *dev, struct device_node *np,
+ unsigned int index, bool power_on)
+{
+ struct of_phandle_args pd_args;
+ struct generic_pm_domain *pd;
+ int ret;
+
+ ret = of_parse_phandle_with_args(np, "power-domains",
+ "#power-domain-cells", index, &pd_args);
+ if (ret < 0)
+ return ret;
+
+ mutex_lock(&gpd_list_lock);
+ pd = genpd_get_from_provider(&pd_args);
+ of_node_put(pd_args.np);
+ if (IS_ERR(pd)) {
+ mutex_unlock(&gpd_list_lock);
+ dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
+ __func__, PTR_ERR(pd));
+ return driver_deferred_probe_check_state(dev);
+ }
+
+ dev_dbg(dev, "adding to PM domain %s\n", pd->name);
+
+ ret = genpd_add_device(pd, dev, NULL);
+ mutex_unlock(&gpd_list_lock);
+
+ if (ret < 0) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to add to PM domain %s: %d",
+ pd->name, ret);
+ return ret;
+ }
+
+ dev->pm_domain->detach = genpd_dev_pm_detach;
+ dev->pm_domain->sync = genpd_dev_pm_sync;
+
+ if (power_on) {
+ genpd_lock(pd);
+ ret = genpd_power_on(pd, 0);
+ genpd_unlock(pd);
+ }
+
+ if (ret)
+ genpd_remove_device(pd, dev);
+
+ return ret ? -EPROBE_DEFER : 1;
+}
+
+/**
+ * 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.
+ *
+ * Returns 1 on successfully attached PM domain, 0 when the device don't need a
+ * PM domain or when multiple power-domains exists for it, else a negative error
+ * code. Note that if a power-domain exists for the device, but it cannot be
+ * found or turned on, then return -EPROBE_DEFER to ensure that the device is
+ * not probed and to re-try again later.
+ */
+int genpd_dev_pm_attach(struct device *dev)
+{
+ if (!dev->of_node)
+ return 0;
+
+ /*
+ * Devices with multiple PM domains must be attached separately, as we
+ * can only attach one PM domain per device.
+ */
+ if (of_count_phandle_with_args(dev->of_node, "power-domains",
+ "#power-domain-cells") != 1)
+ return 0;
+
+ return __genpd_dev_pm_attach(dev, dev->of_node, 0, true);
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach);
+
+/**
+ * genpd_dev_pm_attach_by_id - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @index: The index of the PM domain.
+ *
+ * Parse device's OF node to find a PM domain specifier at the provided @index.
+ * If such is found, creates a virtual device and attaches it to the retrieved
+ * pm_domain ops. To deal with detaching of the virtual device, the ->detach()
+ * callback in the struct dev_pm_domain are assigned to genpd_dev_pm_detach().
+ *
+ * Returns the created virtual device if successfully attached PM domain, NULL
+ * when the device don't need a PM domain, else an ERR_PTR() in case of
+ * failures. If a power-domain exists for the device, but cannot be found or
+ * turned on, then ERR_PTR(-EPROBE_DEFER) is returned to ensure that the device
+ * is not probed and to re-try again later.
+ */
+struct device *genpd_dev_pm_attach_by_id(struct device *dev,
+ unsigned int index)
+{
+ struct device *genpd_dev;
+ int num_domains;
+ int ret;
+
+ if (!dev->of_node)
+ return NULL;
+
+ /* Deal only with devices using multiple PM domains. */
+ num_domains = of_count_phandle_with_args(dev->of_node, "power-domains",
+ "#power-domain-cells");
+ if (num_domains < 2 || index >= num_domains)
+ return NULL;
+
+ /* Allocate and register device on the genpd bus. */
+ genpd_dev = kzalloc(sizeof(*genpd_dev), GFP_KERNEL);
+ if (!genpd_dev)
+ return ERR_PTR(-ENOMEM);
+
+ dev_set_name(genpd_dev, "genpd:%u:%s", index, dev_name(dev));
+ genpd_dev->bus = &genpd_bus_type;
+ genpd_dev->release = genpd_release_dev;
+
+ ret = device_register(genpd_dev);
+ if (ret) {
+ kfree(genpd_dev);
+ return ERR_PTR(ret);
+ }
+
+ /* Try to attach the device to the PM domain at the specified index. */
+ ret = __genpd_dev_pm_attach(genpd_dev, dev->of_node, index, false);
+ if (ret < 1) {
+ device_unregister(genpd_dev);
+ return ret ? ERR_PTR(ret) : NULL;
+ }
+
+ pm_runtime_enable(genpd_dev);
+ genpd_queue_power_off_work(dev_to_genpd(genpd_dev));
+
+ return genpd_dev;
+}
+EXPORT_SYMBOL_GPL(genpd_dev_pm_attach_by_id);
+
+/**
+ * genpd_dev_pm_attach_by_name - Associate a device with one of its PM domains.
+ * @dev: The device used to lookup the PM domain.
+ * @name: The name of the PM domain.
+ *
+ * Parse device's OF node to find a PM domain specifier using the
+ * power-domain-names DT property. For further description see
+ * genpd_dev_pm_attach_by_id().
+ */
+struct device *genpd_dev_pm_attach_by_name(struct device *dev, char *name)
+{
+ int index;
+
+ if (!dev->of_node)
+ return NULL;
+
+ index = of_property_match_string(dev->of_node, "power-domain-names",
+ name);
+ if (index < 0)
+ return NULL;
+
+ return genpd_dev_pm_attach_by_id(dev, index);
+}
+
+static const struct of_device_id idle_state_match[] = {
+ { .compatible = "domain-idle-state", },
+ { }
+};
+
+static int genpd_parse_state(struct genpd_power_state *genpd_state,
+ struct device_node *state_node)
+{
+ int err;
+ u32 residency;
+ u32 entry_latency, exit_latency;
+
+ err = of_property_read_u32(state_node, "entry-latency-us",
+ &entry_latency);
+ if (err) {
+ pr_debug(" * %pOF missing entry-latency-us property\n",
+ state_node);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32(state_node, "exit-latency-us",
+ &exit_latency);
+ if (err) {
+ pr_debug(" * %pOF missing exit-latency-us property\n",
+ state_node);
+ return -EINVAL;
+ }
+
+ err = of_property_read_u32(state_node, "min-residency-us", &residency);
+ if (!err)
+ genpd_state->residency_ns = 1000 * residency;
+
+ genpd_state->power_on_latency_ns = 1000 * exit_latency;
+ genpd_state->power_off_latency_ns = 1000 * entry_latency;
+ genpd_state->fwnode = &state_node->fwnode;
+
+ return 0;
+}
+
+static int genpd_iterate_idle_states(struct device_node *dn,
+ struct genpd_power_state *states)
+{
+ int ret;
+ struct of_phandle_iterator it;
+ struct device_node *np;
+ int i = 0;
+
+ ret = of_count_phandle_with_args(dn, "domain-idle-states", NULL);
+ if (ret <= 0)
+ return ret;
+
+ /* Loop over the phandles until all the requested entry is found */
+ of_for_each_phandle(&it, ret, dn, "domain-idle-states", NULL, 0) {
+ np = it.node;
+ if (!of_match_node(idle_state_match, np))
+ continue;
+ if (states) {
+ ret = genpd_parse_state(&states[i], np);
+ if (ret) {
+ pr_err("Parsing idle state node %pOF failed with err %d\n",
+ np, ret);
+ of_node_put(np);
+ return ret;
+ }
+ }
+ i++;
+ }
+
+ return i;
+}
+
+/**
+ * of_genpd_parse_idle_states: Return array of idle states for the genpd.
+ *
+ * @dn: The genpd device node
+ * @states: The pointer to which the state array will be saved.
+ * @n: The count of elements in the array returned from this function.
+ *
+ * Returns the device states parsed from the OF node. The memory for the states
+ * is allocated by this function and is the responsibility of the caller to
+ * free the memory after use. If no domain idle states is found it returns
+ * -EINVAL and in case of errors, a negative error code.
+ */
+int of_genpd_parse_idle_states(struct device_node *dn,
+ struct genpd_power_state **states, int *n)
+{
+ struct genpd_power_state *st;
+ int ret;
+
+ ret = genpd_iterate_idle_states(dn, NULL);
+ if (ret <= 0)
+ return ret < 0 ? ret : -EINVAL;
+
+ st = kcalloc(ret, sizeof(*st), GFP_KERNEL);
+ if (!st)
+ return -ENOMEM;
+
+ ret = genpd_iterate_idle_states(dn, st);
+ if (ret <= 0) {
+ kfree(st);
+ return ret < 0 ? ret : -EINVAL;
+ }
+
+ *states = st;
+ *n = ret;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states);
+
+/**
+ * of_genpd_opp_to_performance_state- Gets performance state of device's
+ * power domain corresponding to a DT node's "required-opps" property.
+ *
+ * @dev: Device for which the performance-state needs to be found.
+ * @np: DT node where the "required-opps" property is present. This can be
+ * the device node itself (if it doesn't have an OPP table) or a node
+ * within the OPP table of a device (if device has an OPP table).
+ *
+ * Returns performance state corresponding to the "required-opps" property of
+ * a DT node. This calls platform specific genpd->opp_to_performance_state()
+ * callback to translate power domain OPP to performance state.
+ *
+ * Returns performance state on success and 0 on failure.
+ */
+unsigned int of_genpd_opp_to_performance_state(struct device *dev,
+ struct device_node *np)
+{
+ struct generic_pm_domain *genpd;
+ struct dev_pm_opp *opp;
+ int state = 0;
+
+ genpd = dev_to_genpd(dev);
+ if (IS_ERR(genpd))
+ return 0;
+
+ if (unlikely(!genpd->set_performance_state))
+ return 0;
+
+ genpd_lock(genpd);
+
+ opp = of_dev_pm_opp_find_required_opp(&genpd->dev, np);
+ if (IS_ERR(opp)) {
+ dev_err(dev, "Failed to find required OPP: %ld\n",
+ PTR_ERR(opp));
+ goto unlock;
+ }
+
+ state = genpd->opp_to_performance_state(genpd, opp);
+ dev_pm_opp_put(opp);
+
+unlock:
+ genpd_unlock(genpd);
+
+ return state;
+}
+EXPORT_SYMBOL_GPL(of_genpd_opp_to_performance_state);
+
+static int __init genpd_bus_init(void)
+{
+ return bus_register(&genpd_bus_type);
+}
+core_initcall(genpd_bus_init);
+
+#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */
+
+
+/*** debugfs support ***/
+
+#ifdef CONFIG_DEBUG_FS
+#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 *genpd_debugfs_dir;
+
+/*
+ * TODO: This function is a slightly modified version of rtpm_status_show
+ * from sysfs.c, so generalize it.
+ */
+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 genpd_summary_one(struct seq_file *s,
+ struct generic_pm_domain *genpd)
+{
+ static const char * const status_lookup[] = {
+ [GPD_STATE_ACTIVE] = "on",
+ [GPD_STATE_POWER_OFF] = "off"
+ };
+ struct pm_domain_data *pm_data;
+ const char *kobj_path;
+ struct gpd_link *link;
+ char state[16];
+ int ret;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ if (WARN_ON(genpd->status >= ARRAY_SIZE(status_lookup)))
+ goto exit;
+ if (!genpd_status_on(genpd))
+ snprintf(state, sizeof(state), "%s-%u",
+ status_lookup[genpd->status], genpd->state_idx);
+ else
+ snprintf(state, sizeof(state), "%s",
+ status_lookup[genpd->status]);
+ seq_printf(s, "%-30s %-15s ", genpd->name, state);
+
+ /*
+ * Modifications on the list require holding locks on both
+ * master and slave, so we are safe.
+ * Also genpd->name is immutable.
+ */
+ list_for_each_entry(link, &genpd->master_links, master_node) {
+ seq_printf(s, "%s", link->slave->name);
+ if (!list_is_last(&link->master_node, &genpd->master_links))
+ seq_puts(s, ", ");
+ }
+
+ list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
+ kobj_path = kobject_get_path(&pm_data->dev->kobj,
+ genpd_is_irq_safe(genpd) ?
+ GFP_ATOMIC : 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:
+ genpd_unlock(genpd);
+
+ return 0;
+}
+
+static int genpd_summary_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd;
+ 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;
+
+ list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
+ ret = genpd_summary_one(s, genpd);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&gpd_list_lock);
+
+ return ret;
+}
+
+static int genpd_status_show(struct seq_file *s, void *data)
+{
+ static const char * const status_lookup[] = {
+ [GPD_STATE_ACTIVE] = "on",
+ [GPD_STATE_POWER_OFF] = "off"
+ };
+
+ struct generic_pm_domain *genpd = s->private;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ if (WARN_ON_ONCE(genpd->status >= ARRAY_SIZE(status_lookup)))
+ goto exit;
+
+ if (genpd->status == GPD_STATE_POWER_OFF)
+ seq_printf(s, "%s-%u\n", status_lookup[genpd->status],
+ genpd->state_idx);
+ else
+ seq_printf(s, "%s\n", status_lookup[genpd->status]);
+exit:
+ genpd_unlock(genpd);
+ return ret;
+}
+
+static int genpd_sub_domains_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+ struct gpd_link *link;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ list_for_each_entry(link, &genpd->master_links, master_node)
+ seq_printf(s, "%s\n", link->slave->name);
+
+ genpd_unlock(genpd);
+ return ret;
+}
+
+static int genpd_idle_states_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+ unsigned int i;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ seq_puts(s, "State Time Spent(ms)\n");
+
+ for (i = 0; i < genpd->state_count; i++) {
+ ktime_t delta = 0;
+ s64 msecs;
+
+ if ((genpd->status == GPD_STATE_POWER_OFF) &&
+ (genpd->state_idx == i))
+ delta = ktime_sub(ktime_get(), genpd->accounting_time);
+
+ msecs = ktime_to_ms(
+ ktime_add(genpd->states[i].idle_time, delta));
+ seq_printf(s, "S%-13i %lld\n", i, msecs);
+ }
+
+ genpd_unlock(genpd);
+ return ret;
+}
+
+static int genpd_active_time_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+ ktime_t delta = 0;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ if (genpd->status == GPD_STATE_ACTIVE)
+ delta = ktime_sub(ktime_get(), genpd->accounting_time);
+
+ seq_printf(s, "%lld ms\n", ktime_to_ms(
+ ktime_add(genpd->on_time, delta)));
+
+ genpd_unlock(genpd);
+ return ret;
+}
+
+static int genpd_total_idle_time_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+ ktime_t delta = 0, total = 0;
+ unsigned int i;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ for (i = 0; i < genpd->state_count; i++) {
+
+ if ((genpd->status == GPD_STATE_POWER_OFF) &&
+ (genpd->state_idx == i))
+ delta = ktime_sub(ktime_get(), genpd->accounting_time);
+
+ total = ktime_add(total, genpd->states[i].idle_time);
+ }
+ total = ktime_add(total, delta);
+
+ seq_printf(s, "%lld ms\n", ktime_to_ms(total));
+
+ genpd_unlock(genpd);
+ return ret;
+}
+
+
+static int genpd_devices_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+ struct pm_domain_data *pm_data;
+ const char *kobj_path;
+ int ret = 0;
+
+ ret = genpd_lock_interruptible(genpd);
+ if (ret)
+ return -ERESTARTSYS;
+
+ list_for_each_entry(pm_data, &genpd->dev_list, list_node) {
+ kobj_path = kobject_get_path(&pm_data->dev->kobj,
+ genpd_is_irq_safe(genpd) ?
+ GFP_ATOMIC : GFP_KERNEL);
+ if (kobj_path == NULL)
+ continue;
+
+ seq_printf(s, "%s\n", kobj_path);
+ kfree(kobj_path);
+ }
+
+ genpd_unlock(genpd);
+ return ret;
+}
+
+static int genpd_perf_state_show(struct seq_file *s, void *data)
+{
+ struct generic_pm_domain *genpd = s->private;
+
+ if (genpd_lock_interruptible(genpd))
+ return -ERESTARTSYS;
+
+ seq_printf(s, "%u\n", genpd->performance_state);
+
+ genpd_unlock(genpd);
+ return 0;
+}
+
+#define define_genpd_open_function(name) \
+static int genpd_##name##_open(struct inode *inode, struct file *file) \
+{ \
+ return single_open(file, genpd_##name##_show, inode->i_private); \
+}
+
+define_genpd_open_function(summary);
+define_genpd_open_function(status);
+define_genpd_open_function(sub_domains);
+define_genpd_open_function(idle_states);
+define_genpd_open_function(active_time);
+define_genpd_open_function(total_idle_time);
+define_genpd_open_function(devices);
+define_genpd_open_function(perf_state);
+
+#define define_genpd_debugfs_fops(name) \
+static const struct file_operations genpd_##name##_fops = { \
+ .open = genpd_##name##_open, \
+ .read = seq_read, \
+ .llseek = seq_lseek, \
+ .release = single_release, \
+}
+
+define_genpd_debugfs_fops(summary);
+define_genpd_debugfs_fops(status);
+define_genpd_debugfs_fops(sub_domains);
+define_genpd_debugfs_fops(idle_states);
+define_genpd_debugfs_fops(active_time);
+define_genpd_debugfs_fops(total_idle_time);
+define_genpd_debugfs_fops(devices);
+define_genpd_debugfs_fops(perf_state);
+
+static int __init genpd_debug_init(void)
+{
+ struct dentry *d;
+ struct generic_pm_domain *genpd;
+
+ genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL);
+
+ if (!genpd_debugfs_dir)
+ return -ENOMEM;
+
+ d = debugfs_create_file("pm_genpd_summary", S_IRUGO,
+ genpd_debugfs_dir, NULL, &genpd_summary_fops);
+ if (!d)
+ return -ENOMEM;
+
+ list_for_each_entry(genpd, &gpd_list, gpd_list_node) {
+ d = debugfs_create_dir(genpd->name, genpd_debugfs_dir);
+ if (!d)
+ return -ENOMEM;
+
+ debugfs_create_file("current_state", 0444,
+ d, genpd, &genpd_status_fops);
+ debugfs_create_file("sub_domains", 0444,
+ d, genpd, &genpd_sub_domains_fops);
+ debugfs_create_file("idle_states", 0444,
+ d, genpd, &genpd_idle_states_fops);
+ debugfs_create_file("active_time", 0444,
+ d, genpd, &genpd_active_time_fops);
+ debugfs_create_file("total_idle_time", 0444,
+ d, genpd, &genpd_total_idle_time_fops);
+ debugfs_create_file("devices", 0444,
+ d, genpd, &genpd_devices_fops);
+ if (genpd->set_performance_state)
+ debugfs_create_file("perf_state", 0444,
+ d, genpd, &genpd_perf_state_fops);
+ }
+
+ return 0;
+}
+late_initcall(genpd_debug_init);
+
+static void __exit genpd_debug_exit(void)
+{
+ debugfs_remove_recursive(genpd_debugfs_dir);
+}
+__exitcall(genpd_debug_exit);
+#endif /* CONFIG_DEBUG_FS */