/* * drivers/base/power/domain.c - Common code related to device power domains. * * Copyright (C) 2011 Rafael J. Wysocki , Renesas Electronics Corp. * * This file is released under the GPLv2. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #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) static inline bool irq_safe_dev_in_no_sleep_domain(struct device *dev, struct generic_pm_domain *genpd) { bool ret; ret = pm_runtime_is_irq_safe(dev) && !genpd_is_irq_safe(genpd); /* Warn once if IRQ safe dev in no sleep domain */ if (ret) 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(struct generic_pm_domain *genpd, struct device *dev) { return GENPD_DEV_CALLBACK(genpd, int, stop, dev); } static int genpd_start_dev(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(); } 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 (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; if (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 | PM_QOS_FLAG_REMOTE_WAKEUP); 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; } 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; 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; 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 && pdd->dev) { 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) /** * pm_genpd_present - Check if the given PM domain has been initialized. * @genpd: PM domain to check. */ static bool pm_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 static bool genpd_dev_active_wakeup(struct generic_pm_domain *genpd, struct device *dev) { return GENPD_DEV_CALLBACK(genpd, bool, active_wakeup, dev); } /** * 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)) 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; _genpd_power_off(genpd, false); 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 pm_genpd_prepare(): (1) if the device is enabled * to wake up the system and it has to remain active for this purpose while the * system is in the sleep state and (2) if the device is not enabled to wake up * the system from sleep states and it generally doesn't generate wakeup signals * by itself (those signals are generated on its behalf by other parts of the * system). In the latter case it may be necessary to reconfigure the device's * wakeup settings during system suspend, because it may have been set up to * signal remote wakeup from the system's working state as needed by runtime PM. * Return 'true' in either of the above cases. */ static bool resume_needed(struct device *dev, struct generic_pm_domain *genpd) { bool active_wakeup; if (!device_can_wakeup(dev)) return false; active_wakeup = genpd_dev_active_wakeup(genpd, dev); return device_may_wakeup(dev) ? active_wakeup : !active_wakeup; } /** * pm_genpd_prepare - Start power transition of a device in a PM domain. * @dev: Device to start the transition of. * * Start a power transition of a device (during a system-wide power transition) * under the assumption that its pm_domain field points to the domain member of * an object of type struct generic_pm_domain representing a PM domain * consisting of I/O devices. */ static int pm_genpd_prepare(struct device *dev) { struct generic_pm_domain *genpd; 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) { genpd_lock(genpd); genpd->prepared_count--; genpd_unlock(genpd); } return ret; } /** * pm_genpd_suspend_noirq - Completion of suspend of device in an I/O PM domain. * @dev: Device to suspend. * * Stop the device and remove power from the domain if all devices in it have * been stopped. */ static int pm_genpd_suspend_noirq(struct device *dev) { struct generic_pm_domain *genpd; 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_dev_active_wakeup(genpd, dev)) return 0; if (genpd->dev_ops.stop && genpd->dev_ops.start) { ret = pm_runtime_force_suspend(dev); if (ret) return ret; } genpd_lock(genpd); genpd->suspended_count++; genpd_sync_power_off(genpd, true, 0); genpd_unlock(genpd); return 0; } /** * pm_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 pm_genpd_resume_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; if (dev->power.wakeup_path && genpd_dev_active_wakeup(genpd, dev)) return 0; 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) ret = pm_runtime_force_resume(dev); return ret; } /** * pm_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 pm_genpd_freeze_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; if (genpd->dev_ops.stop && genpd->dev_ops.start) ret = pm_runtime_force_suspend(dev); return ret; } /** * pm_genpd_thaw_noirq - Early thaw of device in an I/O PM domain. * @dev: Device to thaw. * * Start the device, unless power has been removed from the domain already * before the system transition. */ static int pm_genpd_thaw_noirq(struct device *dev) { struct generic_pm_domain *genpd; 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) ret = pm_runtime_force_resume(dev); return ret; } /** * pm_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 pm_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) ret = pm_runtime_force_resume(dev); return ret; } /** * pm_genpd_complete - Complete power transition of a device in a power domain. * @dev: Device to complete the transition of. * * Complete a power transition of a device (during a system-wide power * transition) under the assumption that its pm_domain field points to the * domain member of an object of type struct generic_pm_domain representing * a power domain consisting of I/O devices. */ static void pm_genpd_complete(struct device *dev) { struct generic_pm_domain *genpd; 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 (!pm_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 pm_genpd_prepare NULL #define pm_genpd_suspend_noirq NULL #define pm_genpd_resume_noirq NULL #define pm_genpd_freeze_noirq NULL #define pm_genpd_thaw_noirq NULL #define pm_genpd_restore_noirq NULL #define pm_genpd_complete NULL #endif /* CONFIG_PM_SLEEP */ static struct generic_pm_domain_data *genpd_alloc_dev_data(struct device *dev, struct generic_pm_domain *genpd, 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 = -1; gpd_data->nb.notifier_call = genpd_dev_pm_qos_notifier; spin_lock_irq(&dev->power.lock); if (dev->power.subsys_data->domain_data) { ret = -EINVAL; goto err_free; } dev->power.subsys_data->domain_data = &gpd_data->base; spin_unlock_irq(&dev->power.lock); dev_pm_domain_set(dev, &genpd->domain); 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) { dev_pm_domain_set(dev, NULL); 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 = 0; 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, genpd, td); if (IS_ERR(gpd_data)) return PTR_ERR(gpd_data); genpd_lock(genpd); if (genpd->prepared_count > 0) { ret = -EAGAIN; goto out; } ret = genpd->attach_dev ? genpd->attach_dev(genpd, dev) : 0; if (ret) goto out; genpd->device_count++; genpd->max_off_time_changed = true; list_add_tail(&gpd_data->base.list_node, &genpd->dev_list); out: genpd_unlock(genpd); 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. * @td: Set of PM QoS timing parameters to attach to the device. */ int __pm_genpd_add_device(struct generic_pm_domain *genpd, struct device *dev, struct gpd_timing_data *td) { int ret; mutex_lock(&gpd_list_lock); ret = genpd_add_device(genpd, dev, td); 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; if (genpd->detach_dev) genpd->detach_dev(genpd, dev); list_del_init(&pdd->list_node); genpd_unlock(genpd); 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. * @genpd: PM domain to remove the device from. * @dev: Device to be removed. */ int pm_genpd_remove_device(struct generic_pm_domain *genpd, struct device *dev) { if (!genpd || genpd != genpd_lookup_dev(dev)) 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 *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(link, &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->domain.ops.runtime_suspend = genpd_runtime_suspend; genpd->domain.ops.runtime_resume = genpd_runtime_resume; genpd->domain.ops.prepare = pm_genpd_prepare; genpd->domain.ops.suspend_noirq = pm_genpd_suspend_noirq; genpd->domain.ops.resume_noirq = pm_genpd_resume_noirq; genpd->domain.ops.freeze_noirq = pm_genpd_freeze_noirq; genpd->domain.ops.thaw_noirq = pm_genpd_thaw_noirq; genpd->domain.ops.poweroff_noirq = pm_genpd_suspend_noirq; genpd->domain.ops.restore_noirq = pm_genpd_restore_noirq; genpd->domain.ops.complete = pm_genpd_complete; if (genpd->flags & GENPD_FLAG_PM_CLK) { genpd->dev_ops.stop = pm_clk_suspend; genpd->dev_ops.start = pm_clk_resume; } /* 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; } 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 typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args, void *data); /* * 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) { if (genpdspec->args_count != 0) return ERR_PTR(-EINVAL); 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 %s\n", np->full_name); 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 (pm_genpd_present(genpd)) { ret = genpd_add_provider(np, genpd_xlate_simple, genpd); if (!ret) { genpd->provider = &np->fwnode; genpd->has_provider = true; } } 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) { unsigned int i; int ret = -EINVAL; if (!np || !data) return -EINVAL; mutex_lock(&gpd_list_lock); for (i = 0; i < data->num_domains; i++) { if (!data->domains[i]) continue; if (!pm_genpd_present(data->domains[i])) goto error; data->domains[i]->provider = &np->fwnode; data->domains[i]->has_provider = true; } ret = genpd_add_provider(np, genpd_xlate_onecell, data); if (ret < 0) goto error; mutex_unlock(&gpd_list_lock); return 0; error: while (i--) { if (!data->domains[i]) continue; data->domains[i]->provider = NULL; data->domains[i]->has_provider = false; } 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; struct generic_pm_domain *gpd; mutex_lock(&gpd_list_lock); mutex_lock(&of_genpd_mutex); list_for_each_entry(cp, &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; 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, *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(gpd, &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); /** * 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); } 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); } /** * genpd_dev_pm_attach - Attach a device to its PM domain using DT. * @dev: Device to attach. * * Parse device's OF node to find a PM domain specifier. If such is found, * attaches the device to retrieved pm_domain ops. * * Both generic and legacy Samsung-specific DT bindings are supported to keep * backwards compatibility with existing DTBs. * * Returns 0 on successfully attached PM domain or negative error code. 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) { struct of_phandle_args pd_args; struct generic_pm_domain *pd; unsigned int i; int ret; if (!dev->of_node) return -ENODEV; if (dev->pm_domain) return -EEXIST; ret = of_parse_phandle_with_args(dev->of_node, "power-domains", "#power-domain-cells", 0, &pd_args); if (ret < 0) { if (ret != -ENOENT) return ret; /* * Try legacy Samsung-specific bindings * (for backwards compatibility of DT ABI) */ pd_args.args_count = 0; pd_args.np = of_parse_phandle(dev->of_node, "samsung,power-domain", 0); if (!pd_args.np) return -ENOENT; } 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 -EPROBE_DEFER; } dev_dbg(dev, "adding to PM domain %s\n", pd->name); for (i = 1; i < GENPD_RETRY_MAX_MS; i <<= 1) { ret = genpd_add_device(pd, dev, NULL); if (ret != -EAGAIN) break; mdelay(i); cond_resched(); } 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); goto out; } dev->pm_domain->detach = genpd_dev_pm_detach; dev->pm_domain->sync = genpd_dev_pm_sync; genpd_lock(pd); ret = genpd_power_on(pd, 0); genpd_unlock(pd); out: return ret ? -EPROBE_DEFER : 0; } EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); 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; const struct of_device_id *match_id; match_id = of_match_node(idle_state_match, state_node); if (!match_id) return -EINVAL; err = of_property_read_u32(state_node, "entry-latency-us", &entry_latency); if (err) { pr_debug(" * %s missing entry-latency-us property\n", state_node->full_name); return -EINVAL; } err = of_property_read_u32(state_node, "exit-latency-us", &exit_latency); if (err) { pr_debug(" * %s missing exit-latency-us property\n", state_node->full_name); 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; } /** * 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. */ int of_genpd_parse_idle_states(struct device_node *dn, struct genpd_power_state **states, int *n) { struct genpd_power_state *st; struct device_node *np; int i = 0; int err, ret; int count; struct of_phandle_iterator it; count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); if (count <= 0) return -EINVAL; st = kcalloc(count, sizeof(*st), GFP_KERNEL); if (!st) return -ENOMEM; /* Loop over the phandles until all the requested entry is found */ of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { np = it.node; ret = genpd_parse_state(&st[i++], np); if (ret) { pr_err ("Parsing idle state node %s failed with err %d\n", np->full_name, ret); of_node_put(np); kfree(st); return ret; } } *n = count; *states = st; return 0; } EXPORT_SYMBOL_GPL(of_genpd_parse_idle_states); #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ /*** debugfs support ***/ #ifdef CONFIG_DEBUG_FS #include #include #include #include #include #include static struct dentry *pm_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 pm_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 pm_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 = pm_genpd_summary_one(s, genpd); if (ret) break; } mutex_unlock(&gpd_list_lock); return ret; } static int pm_genpd_summary_open(struct inode *inode, struct file *file) { return single_open(file, pm_genpd_summary_show, NULL); } static const struct file_operations pm_genpd_summary_fops = { .open = pm_genpd_summary_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int __init pm_genpd_debug_init(void) { struct dentry *d; pm_genpd_debugfs_dir = debugfs_create_dir("pm_genpd", NULL); if (!pm_genpd_debugfs_dir) return -ENOMEM; d = debugfs_create_file("pm_genpd_summary", S_IRUGO, pm_genpd_debugfs_dir, NULL, &pm_genpd_summary_fops); if (!d) return -ENOMEM; return 0; } late_initcall(pm_genpd_debug_init); static void __exit pm_genpd_debug_exit(void) { debugfs_remove_recursive(pm_genpd_debugfs_dir); } __exitcall(pm_genpd_debug_exit); #endif /* CONFIG_DEBUG_FS */