diff options
Diffstat (limited to 'drivers/base/power/domain.c')
| -rw-r--r-- | drivers/base/power/domain.c | 3223 |
1 files changed, 3223 insertions, 0 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c new file mode 100644 index 000000000..8a90f08c9 --- /dev/null +++ b/drivers/base/power/domain.c @@ -0,0 +1,3223 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * drivers/base/power/domain.c - Common code related to device power domains. + * + * Copyright (C) 2011 Rafael J. Wysocki <rjw@sisk.pl>, Renesas Electronics Corp. + */ +#define pr_fmt(fmt) "PM: " fmt + +#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 <linux/cpu.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 == GENPD_STATE_ON) +#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) +#define genpd_is_cpu_domain(genpd) (genpd->flags & GENPD_FLAG_CPU_DOMAIN) +#define genpd_is_rpm_always_on(genpd) (genpd->flags & GENPD_FLAG_RPM_ALWAYS_ON) + +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; +} + +static int genpd_runtime_suspend(struct device *dev); + +/* + * 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 *dev_to_genpd_safe(struct device *dev) +{ + if (IS_ERR_OR_NULL(dev) || IS_ERR_OR_NULL(dev->pm_domain)) + return NULL; + + /* A genpd's always have its ->runtime_suspend() callback assigned. */ + if (dev->pm_domain->ops.runtime_suspend == genpd_runtime_suspend) + return pd_to_genpd(dev->pm_domain); + + return NULL; +} + +/* + * 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 == GENPD_STATE_ON) { + 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 + +static int _genpd_reeval_performance_state(struct generic_pm_domain *genpd, + unsigned int state) +{ + struct generic_pm_domain_data *pd_data; + struct pm_domain_data *pdd; + struct gpd_link *link; + + /* New requested state is same as Max requested state */ + if (state == genpd->performance_state) + return state; + + /* New requested state is higher than Max requested state */ + if (state > genpd->performance_state) + return 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; + } + + /* + * Traverse all sub-domains within the domain. This can be + * done without any additional locking as the link->performance_state + * field is protected by the parent genpd->lock, which is already taken. + * + * Also note that link->performance_state (subdomain's performance state + * requirement to parent domain) is different from + * link->child->performance_state (current performance state requirement + * of the devices/sub-domains of the subdomain) and so can have a + * different value. + * + * Note that we also take vote from powered-off sub-domains into account + * as the same is done for devices right now. + */ + list_for_each_entry(link, &genpd->parent_links, parent_node) { + if (link->performance_state > state) + state = link->performance_state; + } + + return state; +} + +static int _genpd_set_performance_state(struct generic_pm_domain *genpd, + unsigned int state, int depth) +{ + struct generic_pm_domain *parent; + struct gpd_link *link; + int parent_state, ret; + + if (state == genpd->performance_state) + return 0; + + /* Propagate to parents of genpd */ + list_for_each_entry(link, &genpd->child_links, child_node) { + parent = link->parent; + + if (!parent->set_performance_state) + continue; + + /* Find parent's performance state */ + ret = dev_pm_opp_xlate_performance_state(genpd->opp_table, + parent->opp_table, + state); + if (unlikely(ret < 0)) + goto err; + + parent_state = ret; + + genpd_lock_nested(parent, depth + 1); + + link->prev_performance_state = link->performance_state; + link->performance_state = parent_state; + parent_state = _genpd_reeval_performance_state(parent, + parent_state); + ret = _genpd_set_performance_state(parent, parent_state, depth + 1); + if (ret) + link->performance_state = link->prev_performance_state; + + genpd_unlock(parent); + + if (ret) + goto err; + } + + ret = genpd->set_performance_state(genpd, state); + if (ret) + goto err; + + genpd->performance_state = state; + return 0; + +err: + /* Encountered an error, lets rollback */ + list_for_each_entry_continue_reverse(link, &genpd->child_links, + child_node) { + parent = link->parent; + + if (!parent->set_performance_state) + continue; + + genpd_lock_nested(parent, depth + 1); + + parent_state = link->prev_performance_state; + link->performance_state = parent_state; + + parent_state = _genpd_reeval_performance_state(parent, + parent_state); + if (_genpd_set_performance_state(parent, parent_state, depth + 1)) { + pr_err("%s: Failed to roll back to %d performance state\n", + parent->name, parent_state); + } + + genpd_unlock(parent); + } + + return ret; +} + +/** + * 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; + unsigned int prev; + int ret; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (unlikely(!genpd->set_performance_state)) + return -EINVAL; + + if (WARN_ON(!dev->power.subsys_data || + !dev->power.subsys_data->domain_data)) + 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; + + state = _genpd_reeval_performance_state(genpd, state); + ret = _genpd_set_performance_state(genpd, state, 0); + if (ret) + gpd_data->performance_state = prev; + + 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; + + /* Notify consumers that we are about to power on. */ + ret = raw_notifier_call_chain_robust(&genpd->power_notifiers, + GENPD_NOTIFY_PRE_ON, + GENPD_NOTIFY_OFF, NULL); + ret = notifier_to_errno(ret); + if (ret) + return ret; + + if (!genpd->power_on) + goto out; + + if (!timed) { + ret = genpd->power_on(genpd); + if (ret) + goto err; + + goto out; + } + + time_start = ktime_get(); + ret = genpd->power_on(genpd); + if (ret) + goto err; + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns <= genpd->states[state_idx].power_on_latency_ns) + goto out; + + 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); + +out: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL); + return 0; +err: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF, + NULL); + 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; + + /* Notify consumers that we are about to power off. */ + ret = raw_notifier_call_chain_robust(&genpd->power_notifiers, + GENPD_NOTIFY_PRE_OFF, + GENPD_NOTIFY_ON, NULL); + ret = notifier_to_errno(ret); + if (ret) + return ret; + + if (!genpd->power_off) + goto out; + + if (!timed) { + ret = genpd->power_off(genpd); + if (ret) + goto busy; + + goto out; + } + + time_start = ktime_get(); + ret = genpd->power_off(genpd); + if (ret) + goto busy; + + elapsed_ns = ktime_to_ns(ktime_sub(ktime_get(), time_start)); + if (elapsed_ns <= genpd->states[state_idx].power_off_latency_ns) + goto out; + + 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); + +out: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_OFF, + NULL); + return 0; +busy: + raw_notifier_call_chain(&genpd->power_notifiers, GENPD_NOTIFY_ON, NULL); + 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; + int ret; + + /* + * 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) || + genpd_is_rpm_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; + + /* Don't power off, if a child domain is waiting to power on. */ + if (atomic_read(&genpd->sd_count) > 0) + return -EBUSY; + + ret = _genpd_power_off(genpd, true); + if (ret) { + genpd->states[genpd->state_idx].rejected++; + return ret; + } + + genpd->status = GENPD_STATE_OFF; + genpd_update_accounting(genpd); + genpd->states[genpd->state_idx].usage++; + + list_for_each_entry(link, &genpd->child_links, child_node) { + genpd_sd_counter_dec(link->parent); + genpd_lock_nested(link->parent, depth + 1); + genpd_power_off(link->parent, false, depth + 1); + genpd_unlock(link->parent); + } + + return 0; +} + +/** + * genpd_power_on - Restore power to a given PM domain and its parents. + * @genpd: PM domain to power up. + * @depth: nesting count for lockdep. + * + * Restore power to @genpd and all of its parents 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 parents' .power_on() callbacks fiddles + * with it. + */ + list_for_each_entry(link, &genpd->child_links, child_node) { + struct generic_pm_domain *parent = link->parent; + + genpd_sd_counter_inc(parent); + + genpd_lock_nested(parent, depth + 1); + ret = genpd_power_on(parent, depth + 1); + genpd_unlock(parent); + + if (ret) { + genpd_sd_counter_dec(parent); + goto err; + } + } + + ret = _genpd_power_on(genpd, true); + if (ret) + goto err; + + genpd->status = GENPD_STATE_ON; + genpd_update_accounting(genpd); + + return 0; + + err: + list_for_each_entry_continue_reverse(link, + &genpd->child_links, + child_node) { + genpd_sd_counter_dec(link->parent); + genpd_lock_nested(link->parent, depth + 1); + genpd_power_off(link->parent, false, depth + 1); + genpd_unlock(link->parent); + } + + return ret; +} + +static int genpd_dev_pm_start(struct device *dev) +{ + struct generic_pm_domain *genpd = dev_to_genpd(dev); + + return genpd_start_dev(genpd, dev); +} + +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); + +#ifdef CONFIG_PM_SLEEP + +/** + * genpd_sync_power_off - Synchronously power off a PM domain and its parents. + * @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 parents. + * + * 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 = GENPD_STATE_OFF; + + list_for_each_entry(link, &genpd->child_links, child_node) { + genpd_sd_counter_dec(link->parent); + + if (use_lock) + genpd_lock_nested(link->parent, depth + 1); + + genpd_sync_power_off(link->parent, use_lock, depth + 1); + + if (use_lock) + genpd_unlock(link->parent); + } +} + +/** + * genpd_sync_power_on - Synchronously power on a PM domain and its parents. + * @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->child_links, child_node) { + genpd_sd_counter_inc(link->parent); + + if (use_lock) + genpd_lock_nested(link->parent, depth + 1); + + genpd_sync_power_on(link->parent, use_lock, depth + 1); + + if (use_lock) + genpd_unlock(link->parent); + } + + _genpd_power_on(genpd, false); + genpd->status = GENPD_STATE_ON; +} + +/** + * 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 = GENPD_STATE_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_safe(dev); + if (!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 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; + } + + 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 void genpd_update_cpumask(struct generic_pm_domain *genpd, + int cpu, bool set, unsigned int depth) +{ + struct gpd_link *link; + + if (!genpd_is_cpu_domain(genpd)) + return; + + list_for_each_entry(link, &genpd->child_links, child_node) { + struct generic_pm_domain *parent = link->parent; + + genpd_lock_nested(parent, depth + 1); + genpd_update_cpumask(parent, cpu, set, depth + 1); + genpd_unlock(parent); + } + + if (set) + cpumask_set_cpu(cpu, genpd->cpus); + else + cpumask_clear_cpu(cpu, genpd->cpus); +} + +static void genpd_set_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, true, 0); +} + +static void genpd_clear_cpumask(struct generic_pm_domain *genpd, int cpu) +{ + if (cpu >= 0) + genpd_update_cpumask(genpd, cpu, false, 0); +} + +static int genpd_get_cpu(struct generic_pm_domain *genpd, struct device *dev) +{ + int cpu; + + if (!genpd_is_cpu_domain(genpd)) + return -1; + + for_each_possible_cpu(cpu) { + if (get_cpu_device(cpu) == dev) + return cpu; + } + + return -1; +} + +static int genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, + struct device *base_dev) +{ + 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); + if (IS_ERR(gpd_data)) + return PTR_ERR(gpd_data); + + gpd_data->cpu = genpd_get_cpu(genpd, base_dev); + + ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0; + if (ret) + goto out; + + genpd_lock(genpd); + + genpd_set_cpumask(genpd, gpd_data->cpu); + 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, + DEV_PM_QOS_RESUME_LATENCY); + + 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, dev); + 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, + DEV_PM_QOS_RESUME_LATENCY); + + genpd_lock(genpd); + + if (genpd->prepared_count > 0) { + ret = -EAGAIN; + goto out; + } + + genpd->device_count--; + genpd->max_off_time_changed = true; + + genpd_clear_cpumask(genpd, gpd_data->cpu); + 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, DEV_PM_QOS_RESUME_LATENCY); + + 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 = dev_to_genpd_safe(dev); + + if (!genpd) + return -EINVAL; + + return genpd_remove_device(genpd, dev); +} +EXPORT_SYMBOL_GPL(pm_genpd_remove_device); + +/** + * dev_pm_genpd_add_notifier - Add a genpd power on/off notifier for @dev + * + * @dev: Device that should be associated with the notifier + * @nb: The notifier block to register + * + * Users may call this function to add a genpd power on/off notifier for an + * attached @dev. Only one notifier per device is allowed. The notifier is + * sent when genpd is powering on/off the PM domain. + * + * It is assumed that the user 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_add_notifier(struct device *dev, struct notifier_block *nb) +{ + struct generic_pm_domain *genpd; + struct generic_pm_domain_data *gpd_data; + int ret; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (WARN_ON(!dev->power.subsys_data || + !dev->power.subsys_data->domain_data)) + return -EINVAL; + + gpd_data = to_gpd_data(dev->power.subsys_data->domain_data); + if (gpd_data->power_nb) + return -EEXIST; + + genpd_lock(genpd); + ret = raw_notifier_chain_register(&genpd->power_notifiers, nb); + genpd_unlock(genpd); + + if (ret) { + dev_warn(dev, "failed to add notifier for PM domain %s\n", + genpd->name); + return ret; + } + + gpd_data->power_nb = nb; + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_add_notifier); + +/** + * dev_pm_genpd_remove_notifier - Remove a genpd power on/off notifier for @dev + * + * @dev: Device that is associated with the notifier + * + * Users may call this function to remove a genpd power on/off notifier for an + * attached @dev. + * + * It is assumed that the user 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_remove_notifier(struct device *dev) +{ + struct generic_pm_domain *genpd; + struct generic_pm_domain_data *gpd_data; + int ret; + + genpd = dev_to_genpd_safe(dev); + if (!genpd) + return -ENODEV; + + if (WARN_ON(!dev->power.subsys_data || + !dev->power.subsys_data->domain_data)) + return -EINVAL; + + gpd_data = to_gpd_data(dev->power.subsys_data->domain_data); + if (!gpd_data->power_nb) + return -ENODEV; + + genpd_lock(genpd); + ret = raw_notifier_chain_unregister(&genpd->power_notifiers, + gpd_data->power_nb); + genpd_unlock(genpd); + + if (ret) { + dev_warn(dev, "failed to remove notifier for PM domain %s\n", + genpd->name); + return ret; + } + + gpd_data->power_nb = NULL; + return 0; +} +EXPORT_SYMBOL_GPL(dev_pm_genpd_remove_notifier); + +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->parent_links, parent_node) { + if (itr->child == subdomain && itr->parent == genpd) { + ret = -EINVAL; + goto out; + } + } + + link->parent = genpd; + list_add_tail(&link->parent_node, &genpd->parent_links); + link->child = subdomain; + list_add_tail(&link->child_node, &subdomain->child_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: Leader 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: Leader 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->parent_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->parent_links, parent_node) { + if (link->child != subdomain) + continue; + + list_del(&link->parent_node); + list_del(&link->child_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 void genpd_free_default_power_state(struct genpd_power_state *states, + unsigned int state_count) +{ + kfree(states); +} + +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_states = genpd_free_default_power_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->parent_links); + INIT_LIST_HEAD(&genpd->child_links); + INIT_LIST_HEAD(&genpd->dev_list); + RAW_INIT_NOTIFIER_HEAD(&genpd->power_notifiers); + 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 ? GENPD_STATE_OFF : GENPD_STATE_ON; + 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; + genpd->domain.start = genpd_dev_pm_start; + + 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_is_rpm_always_on(genpd)) && + !genpd_status_on(genpd)) + return -EINVAL; + + if (genpd_is_cpu_domain(genpd) && + !zalloc_cpumask_var(&genpd->cpus, GFP_KERNEL)) + return -ENOMEM; + + /* 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) { + if (genpd_is_cpu_domain(genpd)) + free_cpumask_var(genpd->cpus); + return ret; + } + } else if (!gov && genpd->state_count > 1) { + 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->parent_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->child_links, child_node) { + list_del(&link->parent_node); + list_del(&link->child_node); + kfree(link); + } + + list_del(&genpd->gpd_list_node); + genpd_unlock(genpd); + cancel_work_sync(&genpd->power_off_work); + if (genpd_is_cpu_domain(genpd)) + free_cpumask_var(genpd->cpus); + if (genpd->free_states) + genpd->free_states(genpd->states, genpd->state_count); + + 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; +} + +static bool genpd_present(const struct generic_pm_domain *genpd) +{ + const struct generic_pm_domain *gpd; + + list_for_each_entry(gpd, &gpd_list, gpd_list_node) + if (gpd == genpd) + return true; + return false; +} + +/** + * 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) { + if (ret != -EPROBE_DEFER) + dev_err(&genpd->dev, "Failed to add OPP table: %d\n", + ret); + goto unlock; + } + + /* + * Save table for faster processing while setting performance + * state. + */ + genpd->opp_table = dev_pm_opp_get_opp_table(&genpd->dev); + WARN_ON(IS_ERR(genpd->opp_table)); + } + + ret = genpd_add_provider(np, genpd_xlate_simple, genpd); + if (ret) { + if (genpd->set_performance_state) { + dev_pm_opp_put_opp_table(genpd->opp_table); + 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) { + if (ret != -EPROBE_DEFER) + dev_err(&genpd->dev, "Failed to add OPP table for index %d: %d\n", + i, ret); + goto error; + } + + /* + * Save table for faster processing while setting + * performance state. + */ + genpd->opp_table = dev_pm_opp_get_opp_table_indexed(&genpd->dev, i); + WARN_ON(IS_ERR(genpd->opp_table)); + } + + 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_put_opp_table(genpd->opp_table); + 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_put_opp_table(gpd->opp_table); + 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, dev); + +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_subdomain - Remove a subdomain from 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 removes the subdomain from the parent PM domain. Returns a + * negative error code on failure. + */ +int of_genpd_remove_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 = pm_genpd_remove_subdomain(parent, subdomain); + +out: + mutex_unlock(&gpd_list_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(of_genpd_remove_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) +{ + of_node_put(dev->of_node); + 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 *base_dev, + 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(dev->of_node, "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(base_dev); + } + + dev_dbg(dev, "adding to PM domain %s\n", pd->name); + + ret = genpd_add_device(pd, dev, base_dev); + 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, 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 *virt_dev; + int num_domains; + int ret; + + if (!dev->of_node) + return NULL; + + /* Verify that the index is within a valid range. */ + num_domains = of_count_phandle_with_args(dev->of_node, "power-domains", + "#power-domain-cells"); + if (index >= num_domains) + return NULL; + + /* Allocate and register device on the genpd bus. */ + virt_dev = kzalloc(sizeof(*virt_dev), GFP_KERNEL); + if (!virt_dev) + return ERR_PTR(-ENOMEM); + + dev_set_name(virt_dev, "genpd:%u:%s", index, dev_name(dev)); + virt_dev->bus = &genpd_bus_type; + virt_dev->release = genpd_release_dev; + virt_dev->of_node = of_node_get(dev->of_node); + + ret = device_register(virt_dev); + if (ret) { + put_device(virt_dev); + return ERR_PTR(ret); + } + + /* Try to attach the device to the PM domain at the specified index. */ + ret = __genpd_dev_pm_attach(virt_dev, dev, index, false); + if (ret < 1) { + device_unregister(virt_dev); + return ret ? ERR_PTR(ret) : NULL; + } + + pm_runtime_enable(virt_dev); + genpd_queue_power_off_work(dev_to_genpd(virt_dev)); + + return virt_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, const 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 = 1000LL * residency; + + genpd_state->power_on_latency_ns = 1000LL * exit_latency; + genpd_state->power_off_latency_ns = 1000LL * 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 == -ENOENT ? 0 : 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 (!of_device_is_available(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 any or zero compatible domain idle states is + * found it returns 0 and in case of errors, a negative error code is returned. + */ +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; + + if (!ret) { + *states = NULL; + *n = 0; + return 0; + } + + 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); + +/** + * pm_genpd_opp_to_performance_state - Gets performance state of the genpd from its OPP node. + * + * @genpd_dev: Genpd's device for which the performance-state needs to be found. + * @opp: struct dev_pm_opp of the OPP for which we need to find performance + * state. + * + * Returns performance state encoded in the OPP of the genpd. 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 pm_genpd_opp_to_performance_state(struct device *genpd_dev, + struct dev_pm_opp *opp) +{ + struct generic_pm_domain *genpd = NULL; + int state; + + genpd = container_of(genpd_dev, struct generic_pm_domain, dev); + + if (unlikely(!genpd->opp_to_performance_state)) + return 0; + + genpd_lock(genpd); + state = genpd->opp_to_performance_state(genpd, opp); + genpd_unlock(genpd); + + return state; +} +EXPORT_SYMBOL_GPL(pm_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[] = { + [GENPD_STATE_ON] = "on", + [GENPD_STATE_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 + * parent and child, so we are safe. + * Also genpd->name is immutable. + */ + list_for_each_entry(link, &genpd->parent_links, parent_node) { + seq_printf(s, "%s", link->child->name); + if (!list_is_last(&link->parent_node, &genpd->parent_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 summary_show(struct seq_file *s, void *data) +{ + struct generic_pm_domain *genpd; + int ret = 0; + + seq_puts(s, "domain status children\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 status_show(struct seq_file *s, void *data) +{ + static const char * const status_lookup[] = { + [GENPD_STATE_ON] = "on", + [GENPD_STATE_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 == GENPD_STATE_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 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->parent_links, parent_node) + seq_printf(s, "%s\n", link->child->name); + + genpd_unlock(genpd); + return ret; +} + +static int 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) Usage Rejected\n"); + + for (i = 0; i < genpd->state_count; i++) { + ktime_t delta = 0; + s64 msecs; + + if ((genpd->status == GENPD_STATE_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 %-14lld %-14llu %llu\n", i, msecs, + genpd->states[i].usage, genpd->states[i].rejected); + } + + genpd_unlock(genpd); + return ret; +} + +static int 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 == GENPD_STATE_ON) + 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 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 == GENPD_STATE_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 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 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_SHOW_ATTRIBUTE(summary); +DEFINE_SHOW_ATTRIBUTE(status); +DEFINE_SHOW_ATTRIBUTE(sub_domains); +DEFINE_SHOW_ATTRIBUTE(idle_states); +DEFINE_SHOW_ATTRIBUTE(active_time); +DEFINE_SHOW_ATTRIBUTE(total_idle_time); +DEFINE_SHOW_ATTRIBUTE(devices); +DEFINE_SHOW_ATTRIBUTE(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); + + debugfs_create_file("pm_genpd_summary", S_IRUGO, genpd_debugfs_dir, + NULL, &summary_fops); + + list_for_each_entry(genpd, &gpd_list, gpd_list_node) { + d = debugfs_create_dir(genpd->name, genpd_debugfs_dir); + + debugfs_create_file("current_state", 0444, + d, genpd, &status_fops); + debugfs_create_file("sub_domains", 0444, + d, genpd, &sub_domains_fops); + debugfs_create_file("idle_states", 0444, + d, genpd, &idle_states_fops); + debugfs_create_file("active_time", 0444, + d, genpd, &active_time_fops); + debugfs_create_file("total_idle_time", 0444, + d, genpd, &total_idle_time_fops); + debugfs_create_file("devices", 0444, + d, genpd, &devices_fops); + if (genpd->set_performance_state) + debugfs_create_file("perf_state", 0444, + d, 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 */ |