| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| MyungJoo Ham | 1827 | 27.88% | 10 | 12.99% |
| Chanwoo Choi | 1799 | 27.45% | 20 | 25.97% |
| Nishanth Menon | 974 | 14.86% | 13 | 16.88% |
| Rajagopal Venkat | 534 | 8.15% | 4 | 5.19% |
| Lukasz Luba | 449 | 6.85% | 4 | 5.19% |
| Jonghwa Lee | 391 | 5.97% | 1 | 1.30% |
| Enric Balletbò i Serra | 152 | 2.32% | 1 | 1.30% |
| Matthias Kaehlcke | 132 | 2.01% | 2 | 2.60% |
| Greg Kroah-Hartman | 109 | 1.66% | 1 | 1.30% |
| Saravana Kannan | 48 | 0.73% | 1 | 1.30% |
| Vincent Donnefort | 20 | 0.31% | 1 | 1.30% |
| Axel Lin | 19 | 0.29% | 3 | 3.90% |
| Tobias Jakobi | 17 | 0.26% | 2 | 2.60% |
| Ørjan Eide | 15 | 0.23% | 1 | 1.30% |
| Arvind Yadav | 13 | 0.20% | 1 | 1.30% |
| Kees Cook | 12 | 0.18% | 1 | 1.30% |
| Viresh Kumar | 12 | 0.18% | 2 | 2.60% |
| Peter Chen | 10 | 0.15% | 1 | 1.30% |
| Gustavo A. R. Silva | 6 | 0.09% | 1 | 1.30% |
| Sachin Kamat | 5 | 0.08% | 2 | 2.60% |
| Björn Andersson | 5 | 0.08% | 2 | 2.60% |
| Dan Carpenter | 3 | 0.05% | 1 | 1.30% |
| Masahiro Yamada | 1 | 0.02% | 1 | 1.30% |
| Paul Gortmaker | 1 | 0.02% | 1 | 1.30% |
| Total | 6554 | 77 |
/* * devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework * for Non-CPU Devices. * * Copyright (C) 2011 Samsung Electronics * MyungJoo Ham <myungjoo.ham@samsung.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/kernel.h> #include <linux/kmod.h> #include <linux/sched.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/init.h> #include <linux/export.h> #include <linux/slab.h> #include <linux/stat.h> #include <linux/pm_opp.h> #include <linux/devfreq.h> #include <linux/workqueue.h> #include <linux/platform_device.h> #include <linux/list.h> #include <linux/printk.h> #include <linux/hrtimer.h> #include <linux/of.h> #include "governor.h" static struct class *devfreq_class; /* * devfreq core provides delayed work based load monitoring helper * functions. Governors can use these or can implement their own * monitoring mechanism. */ static struct workqueue_struct *devfreq_wq; /* The list of all device-devfreq governors */ static LIST_HEAD(devfreq_governor_list); /* The list of all device-devfreq */ static LIST_HEAD(devfreq_list); static DEFINE_MUTEX(devfreq_list_lock); /** * find_device_devfreq() - find devfreq struct using device pointer * @dev: device pointer used to lookup device devfreq. * * Search the list of device devfreqs and return the matched device's * devfreq info. devfreq_list_lock should be held by the caller. */ static struct devfreq *find_device_devfreq(struct device *dev) { struct devfreq *tmp_devfreq; if (IS_ERR_OR_NULL(dev)) { pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); return ERR_PTR(-EINVAL); } WARN(!mutex_is_locked(&devfreq_list_lock), "devfreq_list_lock must be locked."); list_for_each_entry(tmp_devfreq, &devfreq_list, node) { if (tmp_devfreq->dev.parent == dev) return tmp_devfreq; } return ERR_PTR(-ENODEV); } static unsigned long find_available_min_freq(struct devfreq *devfreq) { struct dev_pm_opp *opp; unsigned long min_freq = 0; opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &min_freq); if (IS_ERR(opp)) min_freq = 0; else dev_pm_opp_put(opp); return min_freq; } static unsigned long find_available_max_freq(struct devfreq *devfreq) { struct dev_pm_opp *opp; unsigned long max_freq = ULONG_MAX; opp = dev_pm_opp_find_freq_floor(devfreq->dev.parent, &max_freq); if (IS_ERR(opp)) max_freq = 0; else dev_pm_opp_put(opp); return max_freq; } /** * devfreq_get_freq_level() - Lookup freq_table for the frequency * @devfreq: the devfreq instance * @freq: the target frequency */ static int devfreq_get_freq_level(struct devfreq *devfreq, unsigned long freq) { int lev; for (lev = 0; lev < devfreq->profile->max_state; lev++) if (freq == devfreq->profile->freq_table[lev]) return lev; return -EINVAL; } static int set_freq_table(struct devfreq *devfreq) { struct devfreq_dev_profile *profile = devfreq->profile; struct dev_pm_opp *opp; unsigned long freq; int i, count; /* Initialize the freq_table from OPP table */ count = dev_pm_opp_get_opp_count(devfreq->dev.parent); if (count <= 0) return -EINVAL; profile->max_state = count; profile->freq_table = devm_kcalloc(devfreq->dev.parent, profile->max_state, sizeof(*profile->freq_table), GFP_KERNEL); if (!profile->freq_table) { profile->max_state = 0; return -ENOMEM; } for (i = 0, freq = 0; i < profile->max_state; i++, freq++) { opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq); if (IS_ERR(opp)) { devm_kfree(devfreq->dev.parent, profile->freq_table); profile->max_state = 0; return PTR_ERR(opp); } dev_pm_opp_put(opp); profile->freq_table[i] = freq; } return 0; } /** * devfreq_update_status() - Update statistics of devfreq behavior * @devfreq: the devfreq instance * @freq: the update target frequency */ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) { int lev, prev_lev, ret = 0; unsigned long cur_time; cur_time = jiffies; /* Immediately exit if previous_freq is not initialized yet. */ if (!devfreq->previous_freq) goto out; prev_lev = devfreq_get_freq_level(devfreq, devfreq->previous_freq); if (prev_lev < 0) { ret = prev_lev; goto out; } devfreq->time_in_state[prev_lev] += cur_time - devfreq->last_stat_updated; lev = devfreq_get_freq_level(devfreq, freq); if (lev < 0) { ret = lev; goto out; } if (lev != prev_lev) { devfreq->trans_table[(prev_lev * devfreq->profile->max_state) + lev]++; devfreq->total_trans++; } out: devfreq->last_stat_updated = cur_time; return ret; } EXPORT_SYMBOL(devfreq_update_status); /** * find_devfreq_governor() - find devfreq governor from name * @name: name of the governor * * Search the list of devfreq governors and return the matched * governor's pointer. devfreq_list_lock should be held by the caller. */ static struct devfreq_governor *find_devfreq_governor(const char *name) { struct devfreq_governor *tmp_governor; if (IS_ERR_OR_NULL(name)) { pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); return ERR_PTR(-EINVAL); } WARN(!mutex_is_locked(&devfreq_list_lock), "devfreq_list_lock must be locked."); list_for_each_entry(tmp_governor, &devfreq_governor_list, node) { if (!strncmp(tmp_governor->name, name, DEVFREQ_NAME_LEN)) return tmp_governor; } return ERR_PTR(-ENODEV); } /** * try_then_request_governor() - Try to find the governor and request the * module if is not found. * @name: name of the governor * * Search the list of devfreq governors and request the module and try again * if is not found. This can happen when both drivers (the governor driver * and the driver that call devfreq_add_device) are built as modules. * devfreq_list_lock should be held by the caller. Returns the matched * governor's pointer. */ static struct devfreq_governor *try_then_request_governor(const char *name) { struct devfreq_governor *governor; int err = 0; if (IS_ERR_OR_NULL(name)) { pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); return ERR_PTR(-EINVAL); } WARN(!mutex_is_locked(&devfreq_list_lock), "devfreq_list_lock must be locked."); governor = find_devfreq_governor(name); if (IS_ERR(governor)) { mutex_unlock(&devfreq_list_lock); if (!strncmp(name, DEVFREQ_GOV_SIMPLE_ONDEMAND, DEVFREQ_NAME_LEN)) err = request_module("governor_%s", "simpleondemand"); else err = request_module("governor_%s", name); /* Restore previous state before return */ mutex_lock(&devfreq_list_lock); if (err) return NULL; governor = find_devfreq_governor(name); } return governor; } static int devfreq_notify_transition(struct devfreq *devfreq, struct devfreq_freqs *freqs, unsigned int state) { if (!devfreq) return -EINVAL; switch (state) { case DEVFREQ_PRECHANGE: srcu_notifier_call_chain(&devfreq->transition_notifier_list, DEVFREQ_PRECHANGE, freqs); break; case DEVFREQ_POSTCHANGE: srcu_notifier_call_chain(&devfreq->transition_notifier_list, DEVFREQ_POSTCHANGE, freqs); break; default: return -EINVAL; } return 0; } static int devfreq_set_target(struct devfreq *devfreq, unsigned long new_freq, u32 flags) { struct devfreq_freqs freqs; unsigned long cur_freq; int err = 0; if (devfreq->profile->get_cur_freq) devfreq->profile->get_cur_freq(devfreq->dev.parent, &cur_freq); else cur_freq = devfreq->previous_freq; freqs.old = cur_freq; freqs.new = new_freq; devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); err = devfreq->profile->target(devfreq->dev.parent, &new_freq, flags); if (err) { freqs.new = cur_freq; devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); return err; } freqs.new = new_freq; devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); if (devfreq_update_status(devfreq, new_freq)) dev_err(&devfreq->dev, "Couldn't update frequency transition information.\n"); devfreq->previous_freq = new_freq; if (devfreq->suspend_freq) devfreq->resume_freq = cur_freq; return err; } /* Load monitoring helper functions for governors use */ /** * update_devfreq() - Reevaluate the device and configure frequency. * @devfreq: the devfreq instance. * * Note: Lock devfreq->lock before calling update_devfreq * This function is exported for governors. */ int update_devfreq(struct devfreq *devfreq) { unsigned long freq, min_freq, max_freq; int err = 0; u32 flags = 0; if (!mutex_is_locked(&devfreq->lock)) { WARN(true, "devfreq->lock must be locked by the caller.\n"); return -EINVAL; } if (!devfreq->governor) return -EINVAL; /* Reevaluate the proper frequency */ err = devfreq->governor->get_target_freq(devfreq, &freq); if (err) return err; /* * Adjust the frequency with user freq, QoS and available freq. * * List from the highest priority * max_freq * min_freq */ max_freq = min(devfreq->scaling_max_freq, devfreq->max_freq); min_freq = max(devfreq->scaling_min_freq, devfreq->min_freq); if (freq < min_freq) { freq = min_freq; flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */ } if (freq > max_freq) { freq = max_freq; flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ } return devfreq_set_target(devfreq, freq, flags); } EXPORT_SYMBOL(update_devfreq); /** * devfreq_monitor() - Periodically poll devfreq objects. * @work: the work struct used to run devfreq_monitor periodically. * */ static void devfreq_monitor(struct work_struct *work) { int err; struct devfreq *devfreq = container_of(work, struct devfreq, work.work); mutex_lock(&devfreq->lock); err = update_devfreq(devfreq); if (err) dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err); queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); mutex_unlock(&devfreq->lock); } /** * devfreq_monitor_start() - Start load monitoring of devfreq instance * @devfreq: the devfreq instance. * * Helper function for starting devfreq device load monitoing. By * default delayed work based monitoring is supported. Function * to be called from governor in response to DEVFREQ_GOV_START * event when device is added to devfreq framework. */ void devfreq_monitor_start(struct devfreq *devfreq) { INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); if (devfreq->profile->polling_ms) queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); } EXPORT_SYMBOL(devfreq_monitor_start); /** * devfreq_monitor_stop() - Stop load monitoring of a devfreq instance * @devfreq: the devfreq instance. * * Helper function to stop devfreq device load monitoing. Function * to be called from governor in response to DEVFREQ_GOV_STOP * event when device is removed from devfreq framework. */ void devfreq_monitor_stop(struct devfreq *devfreq) { cancel_delayed_work_sync(&devfreq->work); } EXPORT_SYMBOL(devfreq_monitor_stop); /** * devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance * @devfreq: the devfreq instance. * * Helper function to suspend devfreq device load monitoing. Function * to be called from governor in response to DEVFREQ_GOV_SUSPEND * event or when polling interval is set to zero. * * Note: Though this function is same as devfreq_monitor_stop(), * intentionally kept separate to provide hooks for collecting * transition statistics. */ void devfreq_monitor_suspend(struct devfreq *devfreq) { mutex_lock(&devfreq->lock); if (devfreq->stop_polling) { mutex_unlock(&devfreq->lock); return; } devfreq_update_status(devfreq, devfreq->previous_freq); devfreq->stop_polling = true; mutex_unlock(&devfreq->lock); cancel_delayed_work_sync(&devfreq->work); } EXPORT_SYMBOL(devfreq_monitor_suspend); /** * devfreq_monitor_resume() - Resume load monitoring of a devfreq instance * @devfreq: the devfreq instance. * * Helper function to resume devfreq device load monitoing. Function * to be called from governor in response to DEVFREQ_GOV_RESUME * event or when polling interval is set to non-zero. */ void devfreq_monitor_resume(struct devfreq *devfreq) { unsigned long freq; mutex_lock(&devfreq->lock); if (!devfreq->stop_polling) goto out; if (!delayed_work_pending(&devfreq->work) && devfreq->profile->polling_ms) queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); devfreq->last_stat_updated = jiffies; devfreq->stop_polling = false; if (devfreq->profile->get_cur_freq && !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) devfreq->previous_freq = freq; out: mutex_unlock(&devfreq->lock); } EXPORT_SYMBOL(devfreq_monitor_resume); /** * devfreq_interval_update() - Update device devfreq monitoring interval * @devfreq: the devfreq instance. * @delay: new polling interval to be set. * * Helper function to set new load monitoring polling interval. Function * to be called from governor in response to DEVFREQ_GOV_INTERVAL event. */ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) { unsigned int cur_delay = devfreq->profile->polling_ms; unsigned int new_delay = *delay; mutex_lock(&devfreq->lock); devfreq->profile->polling_ms = new_delay; if (devfreq->stop_polling) goto out; /* if new delay is zero, stop polling */ if (!new_delay) { mutex_unlock(&devfreq->lock); cancel_delayed_work_sync(&devfreq->work); return; } /* if current delay is zero, start polling with new delay */ if (!cur_delay) { queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); goto out; } /* if current delay is greater than new delay, restart polling */ if (cur_delay > new_delay) { mutex_unlock(&devfreq->lock); cancel_delayed_work_sync(&devfreq->work); mutex_lock(&devfreq->lock); if (!devfreq->stop_polling) queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); } out: mutex_unlock(&devfreq->lock); } EXPORT_SYMBOL(devfreq_interval_update); /** * devfreq_notifier_call() - Notify that the device frequency requirements * has been changed out of devfreq framework. * @nb: the notifier_block (supposed to be devfreq->nb) * @type: not used * @devp: not used * * Called by a notifier that uses devfreq->nb. */ static int devfreq_notifier_call(struct notifier_block *nb, unsigned long type, void *devp) { struct devfreq *devfreq = container_of(nb, struct devfreq, nb); int ret; mutex_lock(&devfreq->lock); devfreq->scaling_min_freq = find_available_min_freq(devfreq); if (!devfreq->scaling_min_freq) { mutex_unlock(&devfreq->lock); return -EINVAL; } devfreq->scaling_max_freq = find_available_max_freq(devfreq); if (!devfreq->scaling_max_freq) { mutex_unlock(&devfreq->lock); return -EINVAL; } ret = update_devfreq(devfreq); mutex_unlock(&devfreq->lock); return ret; } /** * devfreq_dev_release() - Callback for struct device to release the device. * @dev: the devfreq device * * Remove devfreq from the list and release its resources. */ static void devfreq_dev_release(struct device *dev) { struct devfreq *devfreq = to_devfreq(dev); mutex_lock(&devfreq_list_lock); if (IS_ERR(find_device_devfreq(devfreq->dev.parent))) { mutex_unlock(&devfreq_list_lock); dev_warn(&devfreq->dev, "releasing devfreq which doesn't exist\n"); return; } list_del(&devfreq->node); mutex_unlock(&devfreq_list_lock); if (devfreq->profile->exit) devfreq->profile->exit(devfreq->dev.parent); mutex_destroy(&devfreq->lock); kfree(devfreq); } /** * devfreq_add_device() - Add devfreq feature to the device * @dev: the device to add devfreq feature. * @profile: device-specific profile to run devfreq. * @governor_name: name of the policy to choose frequency. * @data: private data for the governor. The devfreq framework does not * touch this value. */ struct devfreq *devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile, const char *governor_name, void *data) { struct devfreq *devfreq; struct devfreq_governor *governor; static atomic_t devfreq_no = ATOMIC_INIT(-1); int err = 0; if (!dev || !profile || !governor_name) { dev_err(dev, "%s: Invalid parameters.\n", __func__); return ERR_PTR(-EINVAL); } mutex_lock(&devfreq_list_lock); devfreq = find_device_devfreq(dev); mutex_unlock(&devfreq_list_lock); if (!IS_ERR(devfreq)) { dev_err(dev, "%s: Unable to create devfreq for the device.\n", __func__); err = -EINVAL; goto err_out; } devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); if (!devfreq) { err = -ENOMEM; goto err_out; } mutex_init(&devfreq->lock); mutex_lock(&devfreq->lock); devfreq->dev.parent = dev; devfreq->dev.class = devfreq_class; devfreq->dev.release = devfreq_dev_release; devfreq->profile = profile; strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); devfreq->previous_freq = profile->initial_freq; devfreq->last_status.current_frequency = profile->initial_freq; devfreq->data = data; devfreq->nb.notifier_call = devfreq_notifier_call; if (!devfreq->profile->max_state && !devfreq->profile->freq_table) { mutex_unlock(&devfreq->lock); err = set_freq_table(devfreq); if (err < 0) goto err_out; mutex_lock(&devfreq->lock); } devfreq->scaling_min_freq = find_available_min_freq(devfreq); if (!devfreq->scaling_min_freq) { mutex_unlock(&devfreq->lock); err = -EINVAL; goto err_dev; } devfreq->min_freq = devfreq->scaling_min_freq; devfreq->scaling_max_freq = find_available_max_freq(devfreq); if (!devfreq->scaling_max_freq) { mutex_unlock(&devfreq->lock); err = -EINVAL; goto err_dev; } devfreq->max_freq = devfreq->scaling_max_freq; devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); atomic_set(&devfreq->suspend_count, 0); dev_set_name(&devfreq->dev, "devfreq%d", atomic_inc_return(&devfreq_no)); err = device_register(&devfreq->dev); if (err) { mutex_unlock(&devfreq->lock); put_device(&devfreq->dev); goto err_out; } devfreq->trans_table = devm_kzalloc(&devfreq->dev, array3_size(sizeof(unsigned int), devfreq->profile->max_state, devfreq->profile->max_state), GFP_KERNEL); devfreq->time_in_state = devm_kcalloc(&devfreq->dev, devfreq->profile->max_state, sizeof(unsigned long), GFP_KERNEL); devfreq->last_stat_updated = jiffies; srcu_init_notifier_head(&devfreq->transition_notifier_list); mutex_unlock(&devfreq->lock); mutex_lock(&devfreq_list_lock); governor = try_then_request_governor(devfreq->governor_name); if (IS_ERR(governor)) { dev_err(dev, "%s: Unable to find governor for the device\n", __func__); err = PTR_ERR(governor); goto err_init; } devfreq->governor = governor; err = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START, NULL); if (err) { dev_err(dev, "%s: Unable to start governor for the device\n", __func__); goto err_init; } list_add(&devfreq->node, &devfreq_list); mutex_unlock(&devfreq_list_lock); return devfreq; err_init: mutex_unlock(&devfreq_list_lock); devfreq_remove_device(devfreq); devfreq = NULL; err_dev: kfree(devfreq); err_out: return ERR_PTR(err); } EXPORT_SYMBOL(devfreq_add_device); /** * devfreq_remove_device() - Remove devfreq feature from a device. * @devfreq: the devfreq instance to be removed * * The opposite of devfreq_add_device(). */ int devfreq_remove_device(struct devfreq *devfreq) { if (!devfreq) return -EINVAL; if (devfreq->governor) devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_STOP, NULL); device_unregister(&devfreq->dev); return 0; } EXPORT_SYMBOL(devfreq_remove_device); static int devm_devfreq_dev_match(struct device *dev, void *res, void *data) { struct devfreq **r = res; if (WARN_ON(!r || !*r)) return 0; return *r == data; } static void devm_devfreq_dev_release(struct device *dev, void *res) { devfreq_remove_device(*(struct devfreq **)res); } /** * devm_devfreq_add_device() - Resource-managed devfreq_add_device() * @dev: the device to add devfreq feature. * @profile: device-specific profile to run devfreq. * @governor_name: name of the policy to choose frequency. * @data: private data for the governor. The devfreq framework does not * touch this value. * * This function manages automatically the memory of devfreq device using device * resource management and simplify the free operation for memory of devfreq * device. */ struct devfreq *devm_devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile, const char *governor_name, void *data) { struct devfreq **ptr, *devfreq; ptr = devres_alloc(devm_devfreq_dev_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) return ERR_PTR(-ENOMEM); devfreq = devfreq_add_device(dev, profile, governor_name, data); if (IS_ERR(devfreq)) { devres_free(ptr); return devfreq; } *ptr = devfreq; devres_add(dev, ptr); return devfreq; } EXPORT_SYMBOL(devm_devfreq_add_device); #ifdef CONFIG_OF /* * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree * @dev - instance to the given device * @index - index into list of devfreq * * return the instance of devfreq device */ struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) { struct device_node *node; struct devfreq *devfreq; if (!dev) return ERR_PTR(-EINVAL); if (!dev->of_node) return ERR_PTR(-EINVAL); node = of_parse_phandle(dev->of_node, "devfreq", index); if (!node) return ERR_PTR(-ENODEV); mutex_lock(&devfreq_list_lock); list_for_each_entry(devfreq, &devfreq_list, node) { if (devfreq->dev.parent && devfreq->dev.parent->of_node == node) { mutex_unlock(&devfreq_list_lock); of_node_put(node); return devfreq; } } mutex_unlock(&devfreq_list_lock); of_node_put(node); return ERR_PTR(-EPROBE_DEFER); } #else struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, int index) { return ERR_PTR(-ENODEV); } #endif /* CONFIG_OF */ EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle); /** * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() * @dev: the device to add devfreq feature. * @devfreq: the devfreq instance to be removed */ void devm_devfreq_remove_device(struct device *dev, struct devfreq *devfreq) { WARN_ON(devres_release(dev, devm_devfreq_dev_release, devm_devfreq_dev_match, devfreq)); } EXPORT_SYMBOL(devm_devfreq_remove_device); /** * devfreq_suspend_device() - Suspend devfreq of a device. * @devfreq: the devfreq instance to be suspended * * This function is intended to be called by the pm callbacks * (e.g., runtime_suspend, suspend) of the device driver that * holds the devfreq. */ int devfreq_suspend_device(struct devfreq *devfreq) { int ret; if (!devfreq) return -EINVAL; if (atomic_inc_return(&devfreq->suspend_count) > 1) return 0; if (devfreq->governor) { ret = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_SUSPEND, NULL); if (ret) return ret; } if (devfreq->suspend_freq) { ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0); if (ret) return ret; } return 0; } EXPORT_SYMBOL(devfreq_suspend_device); /** * devfreq_resume_device() - Resume devfreq of a device. * @devfreq: the devfreq instance to be resumed * * This function is intended to be called by the pm callbacks * (e.g., runtime_resume, resume) of the device driver that * holds the devfreq. */ int devfreq_resume_device(struct devfreq *devfreq) { int ret; if (!devfreq) return -EINVAL; if (atomic_dec_return(&devfreq->suspend_count) >= 1) return 0; if (devfreq->resume_freq) { ret = devfreq_set_target(devfreq, devfreq->resume_freq, 0); if (ret) return ret; } if (devfreq->governor) { ret = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_RESUME, NULL); if (ret) return ret; } return 0; } EXPORT_SYMBOL(devfreq_resume_device); /** * devfreq_suspend() - Suspend devfreq governors and devices * * Called during system wide Suspend/Hibernate cycles for suspending governors * and devices preserving the state for resume. On some platforms the devfreq * device must have precise state (frequency) after resume in order to provide * fully operating setup. */ void devfreq_suspend(void) { struct devfreq *devfreq; int ret; mutex_lock(&devfreq_list_lock); list_for_each_entry(devfreq, &devfreq_list, node) { ret = devfreq_suspend_device(devfreq); if (ret) dev_err(&devfreq->dev, "failed to suspend devfreq device\n"); } mutex_unlock(&devfreq_list_lock); } /** * devfreq_resume() - Resume devfreq governors and devices * * Called during system wide Suspend/Hibernate cycle for resuming governors and * devices that are suspended with devfreq_suspend(). */ void devfreq_resume(void) { struct devfreq *devfreq; int ret; mutex_lock(&devfreq_list_lock); list_for_each_entry(devfreq, &devfreq_list, node) { ret = devfreq_resume_device(devfreq); if (ret) dev_warn(&devfreq->dev, "failed to resume devfreq device\n"); } mutex_unlock(&devfreq_list_lock); } /** * devfreq_add_governor() - Add devfreq governor * @governor: the devfreq governor to be added */ int devfreq_add_governor(struct devfreq_governor *governor) { struct devfreq_governor *g; struct devfreq *devfreq; int err = 0; if (!governor) { pr_err("%s: Invalid parameters.\n", __func__); return -EINVAL; } mutex_lock(&devfreq_list_lock); g = find_devfreq_governor(governor->name); if (!IS_ERR(g)) { pr_err("%s: governor %s already registered\n", __func__, g->name); err = -EINVAL; goto err_out; } list_add(&governor->node, &devfreq_governor_list); list_for_each_entry(devfreq, &devfreq_list, node) { int ret = 0; struct device *dev = devfreq->dev.parent; if (!strncmp(devfreq->governor_name, governor->name, DEVFREQ_NAME_LEN)) { /* The following should never occur */ if (devfreq->governor) { dev_warn(dev, "%s: Governor %s already present\n", __func__, devfreq->governor->name); ret = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_STOP, NULL); if (ret) { dev_warn(dev, "%s: Governor %s stop = %d\n", __func__, devfreq->governor->name, ret); } /* Fall through */ } devfreq->governor = governor; ret = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_START, NULL); if (ret) { dev_warn(dev, "%s: Governor %s start=%d\n", __func__, devfreq->governor->name, ret); } } } err_out: mutex_unlock(&devfreq_list_lock); return err; } EXPORT_SYMBOL(devfreq_add_governor); /** * devfreq_remove_governor() - Remove devfreq feature from a device. * @governor: the devfreq governor to be removed */ int devfreq_remove_governor(struct devfreq_governor *governor) { struct devfreq_governor *g; struct devfreq *devfreq; int err = 0; if (!governor) { pr_err("%s: Invalid parameters.\n", __func__); return -EINVAL; } mutex_lock(&devfreq_list_lock); g = find_devfreq_governor(governor->name); if (IS_ERR(g)) { pr_err("%s: governor %s not registered\n", __func__, governor->name); err = PTR_ERR(g); goto err_out; } list_for_each_entry(devfreq, &devfreq_list, node) { int ret; struct device *dev = devfreq->dev.parent; if (!strncmp(devfreq->governor_name, governor->name, DEVFREQ_NAME_LEN)) { /* we should have a devfreq governor! */ if (!devfreq->governor) { dev_warn(dev, "%s: Governor %s NOT present\n", __func__, governor->name); continue; /* Fall through */ } ret = devfreq->governor->event_handler(devfreq, DEVFREQ_GOV_STOP, NULL); if (ret) { dev_warn(dev, "%s: Governor %s stop=%d\n", __func__, devfreq->governor->name, ret); } devfreq->governor = NULL; } } list_del(&governor->node); err_out: mutex_unlock(&devfreq_list_lock); return err; } EXPORT_SYMBOL(devfreq_remove_governor); static ssize_t governor_show(struct device *dev, struct device_attribute *attr, char *buf) { if (!to_devfreq(dev)->governor) return -EINVAL; return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); } static ssize_t governor_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct devfreq *df = to_devfreq(dev); int ret; char str_governor[DEVFREQ_NAME_LEN + 1]; struct devfreq_governor *governor; ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor); if (ret != 1) return -EINVAL; mutex_lock(&devfreq_list_lock); governor = try_then_request_governor(str_governor); if (IS_ERR(governor)) { ret = PTR_ERR(governor); goto out; } if (df->governor == governor) { ret = 0; goto out; } else if ((df->governor && df->governor->immutable) || governor->immutable) { ret = -EINVAL; goto out; } if (df->governor) { ret = df->governor->event_handler(df, DEVFREQ_GOV_STOP, NULL); if (ret) { dev_warn(dev, "%s: Governor %s not stopped(%d)\n", __func__, df->governor->name, ret); goto out; } } df->governor = governor; strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN); ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); if (ret) dev_warn(dev, "%s: Governor %s not started(%d)\n", __func__, df->governor->name, ret); out: mutex_unlock(&devfreq_list_lock); if (!ret) ret = count; return ret; } static DEVICE_ATTR_RW(governor); static ssize_t available_governors_show(struct device *d, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(d); ssize_t count = 0; mutex_lock(&devfreq_list_lock); /* * The devfreq with immutable governor (e.g., passive) shows * only own governor. */ if (df->governor->immutable) { count = scnprintf(&buf[count], DEVFREQ_NAME_LEN, "%s ", df->governor_name); /* * The devfreq device shows the registered governor except for * immutable governors such as passive governor . */ } else { struct devfreq_governor *governor; list_for_each_entry(governor, &devfreq_governor_list, node) { if (governor->immutable) continue; count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), "%s ", governor->name); } } mutex_unlock(&devfreq_list_lock); /* Truncate the trailing space */ if (count) count--; count += sprintf(&buf[count], "\n"); return count; } static DEVICE_ATTR_RO(available_governors); static ssize_t cur_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { unsigned long freq; struct devfreq *devfreq = to_devfreq(dev); if (devfreq->profile->get_cur_freq && !devfreq->profile->get_cur_freq(devfreq->dev.parent, &freq)) return sprintf(buf, "%lu\n", freq); return sprintf(buf, "%lu\n", devfreq->previous_freq); } static DEVICE_ATTR_RO(cur_freq); static ssize_t target_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); } static DEVICE_ATTR_RO(target_freq); static ssize_t polling_interval_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); } static ssize_t polling_interval_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct devfreq *df = to_devfreq(dev); unsigned int value; int ret; if (!df->governor) return -EINVAL; ret = sscanf(buf, "%u", &value); if (ret != 1) return -EINVAL; df->governor->event_handler(df, DEVFREQ_GOV_INTERVAL, &value); ret = count; return ret; } static DEVICE_ATTR_RW(polling_interval); static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct devfreq *df = to_devfreq(dev); unsigned long value; int ret; ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; mutex_lock(&df->lock); if (value) { if (value > df->max_freq) { ret = -EINVAL; goto unlock; } } else { unsigned long *freq_table = df->profile->freq_table; /* Get minimum frequency according to sorting order */ if (freq_table[0] < freq_table[df->profile->max_state - 1]) value = freq_table[0]; else value = freq_table[df->profile->max_state - 1]; } df->min_freq = value; update_devfreq(df); ret = count; unlock: mutex_unlock(&df->lock); return ret; } static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(dev); return sprintf(buf, "%lu\n", max(df->scaling_min_freq, df->min_freq)); } static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct devfreq *df = to_devfreq(dev); unsigned long value; int ret; ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; mutex_lock(&df->lock); if (value) { if (value < df->min_freq) { ret = -EINVAL; goto unlock; } } else { unsigned long *freq_table = df->profile->freq_table; /* Get maximum frequency according to sorting order */ if (freq_table[0] < freq_table[df->profile->max_state - 1]) value = freq_table[df->profile->max_state - 1]; else value = freq_table[0]; } df->max_freq = value; update_devfreq(df); ret = count; unlock: mutex_unlock(&df->lock); return ret; } static DEVICE_ATTR_RW(min_freq); static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(dev); return sprintf(buf, "%lu\n", min(df->scaling_max_freq, df->max_freq)); } static DEVICE_ATTR_RW(max_freq); static ssize_t available_frequencies_show(struct device *d, struct device_attribute *attr, char *buf) { struct devfreq *df = to_devfreq(d); ssize_t count = 0; int i; mutex_lock(&df->lock); for (i = 0; i < df->profile->max_state; i++) count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), "%lu ", df->profile->freq_table[i]); mutex_unlock(&df->lock); /* Truncate the trailing space */ if (count) count--; count += sprintf(&buf[count], "\n"); return count; } static DEVICE_ATTR_RO(available_frequencies); static ssize_t trans_stat_show(struct device *dev, struct device_attribute *attr, char *buf) { struct devfreq *devfreq = to_devfreq(dev); ssize_t len; int i, j; unsigned int max_state = devfreq->profile->max_state; if (!devfreq->stop_polling && devfreq_update_status(devfreq, devfreq->previous_freq)) return 0; if (max_state == 0) return sprintf(buf, "Not Supported.\n"); len = sprintf(buf, " From : To\n"); len += sprintf(buf + len, " :"); for (i = 0; i < max_state; i++) len += sprintf(buf + len, "%10lu", devfreq->profile->freq_table[i]); len += sprintf(buf + len, " time(ms)\n"); for (i = 0; i < max_state; i++) { if (devfreq->profile->freq_table[i] == devfreq->previous_freq) { len += sprintf(buf + len, "*"); } else { len += sprintf(buf + len, " "); } len += sprintf(buf + len, "%10lu:", devfreq->profile->freq_table[i]); for (j = 0; j < max_state; j++) len += sprintf(buf + len, "%10u", devfreq->trans_table[(i * max_state) + j]); len += sprintf(buf + len, "%10u\n", jiffies_to_msecs(devfreq->time_in_state[i])); } len += sprintf(buf + len, "Total transition : %u\n", devfreq->total_trans); return len; } static DEVICE_ATTR_RO(trans_stat); static struct attribute *devfreq_attrs[] = { &dev_attr_governor.attr, &dev_attr_available_governors.attr, &dev_attr_cur_freq.attr, &dev_attr_available_frequencies.attr, &dev_attr_target_freq.attr, &dev_attr_polling_interval.attr, &dev_attr_min_freq.attr, &dev_attr_max_freq.attr, &dev_attr_trans_stat.attr, NULL, }; ATTRIBUTE_GROUPS(devfreq); static int __init devfreq_init(void) { devfreq_class = class_create(THIS_MODULE, "devfreq"); if (IS_ERR(devfreq_class)) { pr_err("%s: couldn't create class\n", __FILE__); return PTR_ERR(devfreq_class); } devfreq_wq = create_freezable_workqueue("devfreq_wq"); if (!devfreq_wq) { class_destroy(devfreq_class); pr_err("%s: couldn't create workqueue\n", __FILE__); return -ENOMEM; } devfreq_class->dev_groups = devfreq_groups; return 0; } subsys_initcall(devfreq_init); /* * The following are helper functions for devfreq user device drivers with * OPP framework. */ /** * devfreq_recommended_opp() - Helper function to get proper OPP for the * freq value given to target callback. * @dev: The devfreq user device. (parent of devfreq) * @freq: The frequency given to target function * @flags: Flags handed from devfreq framework. * * The callers are required to call dev_pm_opp_put() for the returned OPP after * use. */ struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq, u32 flags) { struct dev_pm_opp *opp; if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) { /* The freq is an upper bound. opp should be lower */ opp = dev_pm_opp_find_freq_floor(dev, freq); /* If not available, use the closest opp */ if (opp == ERR_PTR(-ERANGE)) opp = dev_pm_opp_find_freq_ceil(dev, freq); } else { /* The freq is an lower bound. opp should be higher */ opp = dev_pm_opp_find_freq_ceil(dev, freq); /* If not available, use the closest opp */ if (opp == ERR_PTR(-ERANGE)) opp = dev_pm_opp_find_freq_floor(dev, freq); } return opp; } EXPORT_SYMBOL(devfreq_recommended_opp); /** * devfreq_register_opp_notifier() - Helper function to get devfreq notified * for any changes in the OPP availability * changes * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. */ int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) { return dev_pm_opp_register_notifier(dev, &devfreq->nb); } EXPORT_SYMBOL(devfreq_register_opp_notifier); /** * devfreq_unregister_opp_notifier() - Helper function to stop getting devfreq * notified for any changes in the OPP * availability changes anymore. * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. * * At exit() callback of devfreq_dev_profile, this must be included if * devfreq_recommended_opp is used. */ int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) { return dev_pm_opp_unregister_notifier(dev, &devfreq->nb); } EXPORT_SYMBOL(devfreq_unregister_opp_notifier); static void devm_devfreq_opp_release(struct device *dev, void *res) { devfreq_unregister_opp_notifier(dev, *(struct devfreq **)res); } /** * devm_ devfreq_register_opp_notifier() * - Resource-managed devfreq_register_opp_notifier() * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. */ int devm_devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) { struct devfreq **ptr; int ret; ptr = devres_alloc(devm_devfreq_opp_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) return -ENOMEM; ret = devfreq_register_opp_notifier(dev, devfreq); if (ret) { devres_free(ptr); return ret; } *ptr = devfreq; devres_add(dev, ptr); return 0; } EXPORT_SYMBOL(devm_devfreq_register_opp_notifier); /** * devm_devfreq_unregister_opp_notifier() * - Resource-managed devfreq_unregister_opp_notifier() * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. */ void devm_devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) { WARN_ON(devres_release(dev, devm_devfreq_opp_release, devm_devfreq_dev_match, devfreq)); } EXPORT_SYMBOL(devm_devfreq_unregister_opp_notifier); /** * devfreq_register_notifier() - Register a driver with devfreq * @devfreq: The devfreq object. * @nb: The notifier block to register. * @list: DEVFREQ_TRANSITION_NOTIFIER. */ int devfreq_register_notifier(struct devfreq *devfreq, struct notifier_block *nb, unsigned int list) { int ret = 0; if (!devfreq) return -EINVAL; switch (list) { case DEVFREQ_TRANSITION_NOTIFIER: ret = srcu_notifier_chain_register( &devfreq->transition_notifier_list, nb); break; default: ret = -EINVAL; } return ret; } EXPORT_SYMBOL(devfreq_register_notifier); /* * devfreq_unregister_notifier() - Unregister a driver with devfreq * @devfreq: The devfreq object. * @nb: The notifier block to be unregistered. * @list: DEVFREQ_TRANSITION_NOTIFIER. */ int devfreq_unregister_notifier(struct devfreq *devfreq, struct notifier_block *nb, unsigned int list) { int ret = 0; if (!devfreq) return -EINVAL; switch (list) { case DEVFREQ_TRANSITION_NOTIFIER: ret = srcu_notifier_chain_unregister( &devfreq->transition_notifier_list, nb); break; default: ret = -EINVAL; } return ret; } EXPORT_SYMBOL(devfreq_unregister_notifier); struct devfreq_notifier_devres { struct devfreq *devfreq; struct notifier_block *nb; unsigned int list; }; static void devm_devfreq_notifier_release(struct device *dev, void *res) { struct devfreq_notifier_devres *this = res; devfreq_unregister_notifier(this->devfreq, this->nb, this->list); } /** * devm_devfreq_register_notifier() - Resource-managed devfreq_register_notifier() * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. * @nb: The notifier block to be unregistered. * @list: DEVFREQ_TRANSITION_NOTIFIER. */ int devm_devfreq_register_notifier(struct device *dev, struct devfreq *devfreq, struct notifier_block *nb, unsigned int list) { struct devfreq_notifier_devres *ptr; int ret; ptr = devres_alloc(devm_devfreq_notifier_release, sizeof(*ptr), GFP_KERNEL); if (!ptr) return -ENOMEM; ret = devfreq_register_notifier(devfreq, nb, list); if (ret) { devres_free(ptr); return ret; } ptr->devfreq = devfreq; ptr->nb = nb; ptr->list = list; devres_add(dev, ptr); return 0; } EXPORT_SYMBOL(devm_devfreq_register_notifier); /** * devm_devfreq_unregister_notifier() - Resource-managed devfreq_unregister_notifier() * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. * @nb: The notifier block to be unregistered. * @list: DEVFREQ_TRANSITION_NOTIFIER. */ void devm_devfreq_unregister_notifier(struct device *dev, struct devfreq *devfreq, struct notifier_block *nb, unsigned int list) { WARN_ON(devres_release(dev, devm_devfreq_notifier_release, devm_devfreq_dev_match, devfreq)); } EXPORT_SYMBOL(devm_devfreq_unregister_notifier);
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