diff options
Diffstat (limited to 'drivers/devfreq/devfreq.c')
| -rw-r--r-- | drivers/devfreq/devfreq.c | 1877 |
1 files changed, 1532 insertions, 345 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index e94e619fe050..00979f2e0e27 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -1,33 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * 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/debugfs.h> +#include <linux/devfreq_cooling.h> #include <linux/errno.h> #include <linux/err.h> #include <linux/init.h> -#include <linux/module.h> +#include <linux/export.h> #include <linux/slab.h> #include <linux/stat.h> -#include <linux/opp.h> +#include <linux/pm_opp.h> #include <linux/devfreq.h> +#include <linux/devfreq-governor.h> #include <linux/workqueue.h> #include <linux/platform_device.h> #include <linux/list.h> #include <linux/printk.h> #include <linux/hrtimer.h> -#include "governor.h" +#include <linux/of.h> +#include <linux/pm_qos.h> +#include <linux/units.h> + +#define CREATE_TRACE_POINTS +#include <trace/events/devfreq.h> + +#define IS_SUPPORTED_FLAG(f, name) ((f & DEVFREQ_GOV_FLAG_##name) ? true : false) +#define IS_SUPPORTED_ATTR(f, name) ((f & DEVFREQ_GOV_ATTR_##name) ? true : false) static struct class *devfreq_class; +static struct dentry *devfreq_debugfs; /* * devfreq core provides delayed work based load monitoring helper @@ -42,6 +52,11 @@ static LIST_HEAD(devfreq_governor_list); static LIST_HEAD(devfreq_list); static DEFINE_MUTEX(devfreq_list_lock); +static const char timer_name[][DEVFREQ_NAME_LEN] = { + [DEVFREQ_TIMER_DEFERRABLE] = { "deferrable" }, + [DEVFREQ_TIMER_DELAYED] = { "delayed" }, +}; + /** * find_device_devfreq() - find devfreq struct using device pointer * @dev: device pointer used to lookup device devfreq. @@ -53,12 +68,12 @@ static struct devfreq *find_device_devfreq(struct device *dev) { struct devfreq *tmp_devfreq; - if (unlikely(IS_ERR_OR_NULL(dev))) { + lockdep_assert_held(&devfreq_list_lock); + + 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) @@ -68,6 +83,80 @@ static struct devfreq *find_device_devfreq(struct device *dev) 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_indexed(devfreq->dev.parent, &min_freq, 0); + 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_indexed(devfreq->dev.parent, &max_freq, 0); + if (IS_ERR(opp)) + max_freq = 0; + else + dev_pm_opp_put(opp); + + return max_freq; +} + +/** + * devfreq_get_freq_range() - Get the current freq range + * @devfreq: the devfreq instance + * @min_freq: the min frequency + * @max_freq: the max frequency + * + * This takes into consideration all constraints. + */ +void devfreq_get_freq_range(struct devfreq *devfreq, + unsigned long *min_freq, + unsigned long *max_freq) +{ + unsigned long *freq_table = devfreq->freq_table; + s32 qos_min_freq, qos_max_freq; + + lockdep_assert_held(&devfreq->lock); + + /* + * Initialize minimum/maximum frequency from freq table. + * The devfreq drivers can initialize this in either ascending or + * descending order and devfreq core supports both. + */ + if (freq_table[0] < freq_table[devfreq->max_state - 1]) { + *min_freq = freq_table[0]; + *max_freq = freq_table[devfreq->max_state - 1]; + } else { + *min_freq = freq_table[devfreq->max_state - 1]; + *max_freq = freq_table[0]; + } + + /* Apply constraints from PM QoS */ + qos_min_freq = dev_pm_qos_read_value(devfreq->dev.parent, + DEV_PM_QOS_MIN_FREQUENCY); + qos_max_freq = dev_pm_qos_read_value(devfreq->dev.parent, + DEV_PM_QOS_MAX_FREQUENCY); + *min_freq = max(*min_freq, (unsigned long)HZ_PER_KHZ * qos_min_freq); + if (qos_max_freq != PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE) + *max_freq = min(*max_freq, + (unsigned long)HZ_PER_KHZ * qos_max_freq); + + /* Apply constraints from OPP interface */ + *max_freq = clamp(*max_freq, devfreq->scaling_min_freq, devfreq->scaling_max_freq); + *min_freq = clamp(*min_freq, devfreq->scaling_min_freq, *max_freq); +} +EXPORT_SYMBOL(devfreq_get_freq_range); + /** * devfreq_get_freq_level() - Lookup freq_table for the frequency * @devfreq: the devfreq instance @@ -77,41 +166,88 @@ 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]) + for (lev = 0; lev < devfreq->max_state; lev++) + if (freq == devfreq->freq_table[lev]) return lev; return -EINVAL; } +static int set_freq_table(struct devfreq *devfreq) +{ + 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; + + devfreq->max_state = count; + devfreq->freq_table = devm_kcalloc(devfreq->dev.parent, + devfreq->max_state, + sizeof(*devfreq->freq_table), + GFP_KERNEL); + if (!devfreq->freq_table) + return -ENOMEM; + + for (i = 0, freq = 0; i < devfreq->max_state; i++, freq++) { + opp = dev_pm_opp_find_freq_ceil_indexed(devfreq->dev.parent, &freq, 0); + if (IS_ERR(opp)) { + devm_kfree(devfreq->dev.parent, devfreq->freq_table); + return PTR_ERR(opp); + } + dev_pm_opp_put(opp); + devfreq->freq_table[i] = freq; + } + + return 0; +} + /** * devfreq_update_status() - Update statistics of devfreq behavior * @devfreq: the devfreq instance * @freq: the update target frequency */ -static int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) +int devfreq_update_status(struct devfreq *devfreq, unsigned long freq) { - int lev, prev_lev; - unsigned long cur_time; + int lev, prev_lev, ret = 0; + u64 cur_time; + + lockdep_assert_held(&devfreq->lock); + cur_time = get_jiffies_64(); + + /* 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->stats.time_in_state[prev_lev] += + cur_time - devfreq->stats.last_update; lev = devfreq_get_freq_level(devfreq, freq); - if (lev < 0) - return lev; + if (lev < 0) { + ret = lev; + goto out; + } - cur_time = jiffies; - devfreq->time_in_state[lev] += - cur_time - devfreq->last_stat_updated; - if (freq != devfreq->previous_freq) { - prev_lev = devfreq_get_freq_level(devfreq, - devfreq->previous_freq); - devfreq->trans_table[(prev_lev * - devfreq->profile->max_state) + lev]++; - devfreq->total_trans++; + if (lev != prev_lev) { + devfreq->stats.trans_table[ + (prev_lev * devfreq->max_state) + lev]++; + devfreq->stats.total_trans++; } - devfreq->last_stat_updated = cur_time; - return 0; +out: + devfreq->stats.last_update = cur_time; + return ret; } +EXPORT_SYMBOL(devfreq_update_status); /** * find_devfreq_governor() - find devfreq governor from name @@ -124,12 +260,12 @@ static struct devfreq_governor *find_devfreq_governor(const char *name) { struct devfreq_governor *tmp_governor; - if (unlikely(IS_ERR_OR_NULL(name))) { + lockdep_assert_held(&devfreq_list_lock); + + 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)) @@ -139,25 +275,135 @@ static struct devfreq_governor *find_devfreq_governor(const char *name) return ERR_PTR(-ENODEV); } -/* Load monitoring helper functions for governors use */ +/** + * 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 or an error pointer. + */ +static struct devfreq_governor *try_then_request_governor(const char *name) +{ + struct devfreq_governor *governor; + int err = 0; + + lockdep_assert_held(&devfreq_list_lock); + + if (IS_ERR_OR_NULL(name)) { + pr_err("DEVFREQ: %s: Invalid parameters\n", __func__); + return ERR_PTR(-EINVAL); + } + + 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 (err < 0) ? ERR_PTR(err) : ERR_PTR(-EINVAL); + + 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; + } + + /* + * Print devfreq_frequency trace information between DEVFREQ_PRECHANGE + * and DEVFREQ_POSTCHANGE because for showing the correct frequency + * change order of between devfreq device and passive devfreq device. + */ + if (trace_devfreq_frequency_enabled() && new_freq != cur_freq) + trace_devfreq_frequency(devfreq, new_freq, cur_freq); + + freqs.new = new_freq; + devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); + + if (devfreq_update_status(devfreq, new_freq)) + dev_warn(&devfreq->dev, + "Couldn't update frequency transition information.\n"); + + devfreq->previous_freq = new_freq; + + if (devfreq->suspend_freq) + devfreq->resume_freq = new_freq; + + return err; +} /** - * update_devfreq() - Reevaluate the device and configure frequency. + * devfreq_update_target() - Reevaluate the device and configure frequency + * on the final stage. * @devfreq: the devfreq instance. + * @freq: the new frequency of parent device. This argument + * is only used for devfreq device using passive governor. * - * Note: Lock devfreq->lock before calling update_devfreq - * This function is exported for governors. + * Note: Lock devfreq->lock before calling devfreq_update_target. This function + * should be only used by both update_devfreq() and devfreq governors. */ -int update_devfreq(struct devfreq *devfreq) +int devfreq_update_target(struct devfreq *devfreq, unsigned long freq) { - unsigned long freq; + unsigned long 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; - } + lockdep_assert_held(&devfreq->lock); if (!devfreq->governor) return -EINVAL; @@ -166,35 +412,33 @@ int update_devfreq(struct devfreq *devfreq) err = devfreq->governor->get_target_freq(devfreq, &freq); if (err) return err; + devfreq_get_freq_range(devfreq, &min_freq, &max_freq); - /* - * Adjust the freuqency with user freq and QoS. - * - * List from the highest proiority - * max_freq (probably called by thermal when it's too hot) - * min_freq - */ - - if (devfreq->min_freq && freq < devfreq->min_freq) { - freq = devfreq->min_freq; + if (freq < min_freq) { + freq = min_freq; flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */ } - if (devfreq->max_freq && freq > devfreq->max_freq) { - freq = devfreq->max_freq; + if (freq > max_freq) { + freq = max_freq; flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ } - err = devfreq->profile->target(devfreq->dev.parent, &freq, flags); - if (err) - return err; + return devfreq_set_target(devfreq, freq, flags); +} +EXPORT_SYMBOL(devfreq_update_target); - if (devfreq->profile->freq_table) - if (devfreq_update_status(devfreq, freq)) - dev_err(&devfreq->dev, - "Couldn't update frequency transition information.\n"); +/* Load monitoring helper functions for governors use */ - devfreq->previous_freq = freq; - return err; +/** + * 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) +{ + return devfreq_update_target(devfreq, 0L); } EXPORT_SYMBOL(update_devfreq); @@ -214,26 +458,54 @@ static void devfreq_monitor(struct work_struct *work) if (err) dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err); + if (devfreq->stop_polling) + goto out; + queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); + +out: mutex_unlock(&devfreq->lock); + trace_devfreq_monitor(devfreq); } /** * 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. + * Helper function for starting devfreq device load monitoring. By default, + * deferrable timer is used for load monitoring. But the users can change this + * behavior using the "timer" type in devfreq_dev_profile. This function will be + * called by devfreq governor in response to the DEVFREQ_GOV_START event + * generated while adding a device to the devfreq framework. */ void devfreq_monitor_start(struct devfreq *devfreq) { - INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); + if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) + return; + + mutex_lock(&devfreq->lock); + if (delayed_work_pending(&devfreq->work)) + goto out; + + switch (devfreq->profile->timer) { + case DEVFREQ_TIMER_DEFERRABLE: + INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); + break; + case DEVFREQ_TIMER_DELAYED: + INIT_DELAYED_WORK(&devfreq->work, devfreq_monitor); + break; + default: + goto out; + } + if (devfreq->profile->polling_ms) queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); + +out: + devfreq->stop_polling = false; + mutex_unlock(&devfreq->lock); } EXPORT_SYMBOL(devfreq_monitor_start); @@ -241,12 +513,23 @@ 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 + * Helper function to stop devfreq device load monitoring. 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) { + if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) + return; + + mutex_lock(&devfreq->lock); + if (devfreq->stop_polling) { + mutex_unlock(&devfreq->lock); + return; + } + + devfreq->stop_polling = true; + mutex_unlock(&devfreq->lock); cancel_delayed_work_sync(&devfreq->work); } EXPORT_SYMBOL(devfreq_monitor_stop); @@ -255,7 +538,7 @@ 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 + * Helper function to suspend devfreq device load monitoring. Function * to be called from governor in response to DEVFREQ_GOV_SUSPEND * event or when polling interval is set to zero. * @@ -274,6 +557,10 @@ void devfreq_monitor_suspend(struct devfreq *devfreq) devfreq_update_status(devfreq, devfreq->previous_freq); devfreq->stop_polling = true; mutex_unlock(&devfreq->lock); + + if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) + return; + cancel_delayed_work_sync(&devfreq->work); } EXPORT_SYMBOL(devfreq_monitor_suspend); @@ -282,7 +569,7 @@ 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 + * Helper function to resume devfreq device load monitoring. Function * to be called from governor in response to DEVFREQ_GOV_RESUME * event or when polling interval is set to non-zero. */ @@ -291,6 +578,10 @@ void devfreq_monitor_resume(struct devfreq *devfreq) unsigned long freq; mutex_lock(&devfreq->lock); + + if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) + goto out_update; + if (!devfreq->stop_polling) goto out; @@ -299,7 +590,8 @@ void devfreq_monitor_resume(struct devfreq *devfreq) queue_delayed_work(devfreq_wq, &devfreq->work, msecs_to_jiffies(devfreq->profile->polling_ms)); - devfreq->last_stat_updated = jiffies; +out_update: + devfreq->stats.last_update = get_jiffies_64(); devfreq->stop_polling = false; if (devfreq->profile->get_cur_freq && @@ -312,14 +604,14 @@ out: EXPORT_SYMBOL(devfreq_monitor_resume); /** - * devfreq_interval_update() - Update device devfreq monitoring interval + * devfreq_update_interval() - 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. + * to be called from governor in response to DEVFREQ_GOV_UPDATE_INTERVAL event. */ -void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) +void devfreq_update_interval(struct devfreq *devfreq, unsigned int *delay) { unsigned int cur_delay = devfreq->profile->polling_ms; unsigned int new_delay = *delay; @@ -327,6 +619,9 @@ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) mutex_lock(&devfreq->lock); devfreq->profile->polling_ms = new_delay; + if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) + goto out; + if (devfreq->stop_polling) goto out; @@ -351,16 +646,16 @@ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) mutex_lock(&devfreq->lock); if (!devfreq->stop_polling) queue_delayed_work(devfreq_wq, &devfreq->work, - msecs_to_jiffies(devfreq->profile->polling_ms)); + msecs_to_jiffies(devfreq->profile->polling_ms)); } out: mutex_unlock(&devfreq->lock); } -EXPORT_SYMBOL(devfreq_interval_update); +EXPORT_SYMBOL(devfreq_update_interval); /** * devfreq_notifier_call() - Notify that the device frequency requirements - * has been changed out of devfreq framework. + * has been changed out of devfreq framework. * @nb: the notifier_block (supposed to be devfreq->nb) * @type: not used * @devp: not used @@ -371,69 +666,136 @@ 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; + int err = -EINVAL; mutex_lock(&devfreq->lock); - ret = update_devfreq(devfreq); + + devfreq->scaling_min_freq = find_available_min_freq(devfreq); + if (!devfreq->scaling_min_freq) + goto out; + + devfreq->scaling_max_freq = find_available_max_freq(devfreq); + if (!devfreq->scaling_max_freq) { + devfreq->scaling_max_freq = ULONG_MAX; + goto out; + } + + err = update_devfreq(devfreq); + +out: mutex_unlock(&devfreq->lock); + if (err) + dev_err(devfreq->dev.parent, + "failed to update frequency from OPP notifier (%d)\n", + err); - return ret; + return NOTIFY_OK; } /** - * _remove_devfreq() - Remove devfreq from the list and release its resources. - * @devfreq: the devfreq struct - * @skip: skip calling device_unregister(). + * qos_notifier_call() - Common handler for QoS constraints. + * @devfreq: the devfreq instance. */ -static void _remove_devfreq(struct devfreq *devfreq, bool skip) +static int qos_notifier_call(struct devfreq *devfreq) { - 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); + int err; - if (devfreq->governor) - devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_STOP, NULL); + mutex_lock(&devfreq->lock); + err = update_devfreq(devfreq); + mutex_unlock(&devfreq->lock); + if (err) + dev_err(devfreq->dev.parent, + "failed to update frequency from PM QoS (%d)\n", + err); - if (devfreq->profile->exit) - devfreq->profile->exit(devfreq->dev.parent); + return NOTIFY_OK; +} - if (!skip && get_device(&devfreq->dev)) { - device_unregister(&devfreq->dev); - put_device(&devfreq->dev); - } +/** + * qos_min_notifier_call() - Callback for QoS min_freq changes. + * @nb: Should be devfreq->nb_min + * @val: not used + * @ptr: not used + */ +static int qos_min_notifier_call(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + return qos_notifier_call(container_of(nb, struct devfreq, nb_min)); +} - mutex_destroy(&devfreq->lock); - kfree(devfreq); +/** + * qos_max_notifier_call() - Callback for QoS max_freq changes. + * @nb: Should be devfreq->nb_max + * @val: not used + * @ptr: not used + */ +static int qos_max_notifier_call(struct notifier_block *nb, + unsigned long val, void *ptr) +{ + return qos_notifier_call(container_of(nb, struct devfreq, nb_max)); } /** * devfreq_dev_release() - Callback for struct device to release the device. * @dev: the devfreq device * - * This calls _remove_devfreq() if _remove_devfreq() is not called. - * Note that devfreq_dev_release() could be called by _remove_devfreq() as - * well as by others unregistering the device. + * Remove devfreq from the list and release its resources. */ static void devfreq_dev_release(struct device *dev) { struct devfreq *devfreq = to_devfreq(dev); + int err; + + mutex_lock(&devfreq_list_lock); + list_del(&devfreq->node); + mutex_unlock(&devfreq_list_lock); + + err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_max, + DEV_PM_QOS_MAX_FREQUENCY); + if (err && err != -ENOENT) + dev_warn(dev->parent, + "Failed to remove max_freq notifier: %d\n", err); + err = dev_pm_qos_remove_notifier(devfreq->dev.parent, &devfreq->nb_min, + DEV_PM_QOS_MIN_FREQUENCY); + if (err && err != -ENOENT) + dev_warn(dev->parent, + "Failed to remove min_freq notifier: %d\n", err); + + if (dev_pm_qos_request_active(&devfreq->user_max_freq_req)) { + err = dev_pm_qos_remove_request(&devfreq->user_max_freq_req); + if (err < 0) + dev_warn(dev->parent, + "Failed to remove max_freq request: %d\n", err); + } + if (dev_pm_qos_request_active(&devfreq->user_min_freq_req)) { + err = dev_pm_qos_remove_request(&devfreq->user_min_freq_req); + if (err < 0) + dev_warn(dev->parent, + "Failed to remove min_freq request: %d\n", err); + } - _remove_devfreq(devfreq, true); + if (devfreq->profile->exit) + devfreq->profile->exit(devfreq->dev.parent); + + if (devfreq->opp_table) + dev_pm_opp_put_opp_table(devfreq->opp_table); + + mutex_destroy(&devfreq->lock); + srcu_cleanup_notifier_head(&devfreq->transition_notifier_list); + kfree(devfreq); } +static void create_sysfs_files(struct devfreq *devfreq, + const struct devfreq_governor *gov); +static void remove_sysfs_files(struct devfreq *devfreq, + const struct devfreq_governor *gov); + /** * 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. + * @data: devfreq driver pass to governors, governor should not change it. */ struct devfreq *devfreq_add_device(struct device *dev, struct devfreq_dev_profile *profile, @@ -453,15 +815,14 @@ struct devfreq *devfreq_add_device(struct device *dev, 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. It already has one.\n", __func__); + dev_err(dev, "%s: devfreq device already exists!\n", + __func__); err = -EINVAL; goto err_out; } devfreq = kzalloc(sizeof(struct devfreq), GFP_KERNEL); if (!devfreq) { - dev_err(dev, "%s: Unable to create devfreq for the device\n", - __func__); err = -ENOMEM; goto err_out; } @@ -470,53 +831,150 @@ struct devfreq *devfreq_add_device(struct device *dev, mutex_lock(&devfreq->lock); devfreq->dev.parent = dev; devfreq->dev.class = devfreq_class; + devfreq->dev.groups = profile->dev_groups; devfreq->dev.release = devfreq_dev_release; + INIT_LIST_HEAD(&devfreq->node); 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; - devfreq->trans_table = devm_kzalloc(dev, sizeof(unsigned int) * - devfreq->profile->max_state * - devfreq->profile->max_state, - GFP_KERNEL); - devfreq->time_in_state = devm_kzalloc(dev, sizeof(unsigned int) * - devfreq->profile->max_state, - GFP_KERNEL); - devfreq->last_stat_updated = jiffies; + if (devfreq->profile->timer < 0 + || devfreq->profile->timer >= DEVFREQ_TIMER_NUM) { + mutex_unlock(&devfreq->lock); + err = -EINVAL; + goto err_dev; + } + + if (!devfreq->profile->max_state || !devfreq->profile->freq_table) { + mutex_unlock(&devfreq->lock); + err = set_freq_table(devfreq); + if (err < 0) + goto err_dev; + mutex_lock(&devfreq->lock); + } else { + devfreq->freq_table = devfreq->profile->freq_table; + devfreq->max_state = devfreq->profile->max_state; + } + + devfreq->scaling_min_freq = find_available_min_freq(devfreq); + if (!devfreq->scaling_min_freq) { + mutex_unlock(&devfreq->lock); + err = -EINVAL; + goto err_dev; + } + + devfreq->scaling_max_freq = find_available_max_freq(devfreq); + if (!devfreq->scaling_max_freq) { + mutex_unlock(&devfreq->lock); + err = -EINVAL; + goto err_dev; + } + + devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); + devfreq->opp_table = dev_pm_opp_get_opp_table(dev); + if (IS_ERR(devfreq->opp_table)) + devfreq->opp_table = NULL; + + atomic_set(&devfreq->suspend_count, 0); dev_set_name(&devfreq->dev, "%s", dev_name(dev)); err = device_register(&devfreq->dev); if (err) { + mutex_unlock(&devfreq->lock); put_device(&devfreq->dev); + goto err_out; + } + + devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev, + array3_size(sizeof(unsigned int), + devfreq->max_state, + devfreq->max_state), + GFP_KERNEL); + if (!devfreq->stats.trans_table) { mutex_unlock(&devfreq->lock); - goto err_dev; + err = -ENOMEM; + goto err_devfreq; } + devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev, + devfreq->max_state, + sizeof(*devfreq->stats.time_in_state), + GFP_KERNEL); + if (!devfreq->stats.time_in_state) { + mutex_unlock(&devfreq->lock); + err = -ENOMEM; + goto err_devfreq; + } + + devfreq->stats.total_trans = 0; + devfreq->stats.last_update = get_jiffies_64(); + + srcu_init_notifier_head(&devfreq->transition_notifier_list); + mutex_unlock(&devfreq->lock); + err = dev_pm_qos_add_request(dev, &devfreq->user_min_freq_req, + DEV_PM_QOS_MIN_FREQUENCY, 0); + if (err < 0) + goto err_devfreq; + err = dev_pm_qos_add_request(dev, &devfreq->user_max_freq_req, + DEV_PM_QOS_MAX_FREQUENCY, + PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE); + if (err < 0) + goto err_devfreq; + + devfreq->nb_min.notifier_call = qos_min_notifier_call; + err = dev_pm_qos_add_notifier(dev, &devfreq->nb_min, + DEV_PM_QOS_MIN_FREQUENCY); + if (err) + goto err_devfreq; + + devfreq->nb_max.notifier_call = qos_max_notifier_call; + err = dev_pm_qos_add_notifier(dev, &devfreq->nb_max, + DEV_PM_QOS_MAX_FREQUENCY); + if (err) + goto err_devfreq; + mutex_lock(&devfreq_list_lock); - list_add(&devfreq->node, &devfreq_list); - governor = find_devfreq_governor(devfreq->governor_name); - if (!IS_ERR(governor)) - devfreq->governor = governor; - if (devfreq->governor) - err = devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_START, NULL); - mutex_unlock(&devfreq_list_lock); - if (err) { - dev_err(dev, "%s: Unable to start governor for the device\n", + governor = try_then_request_governor(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_probe(dev, err, + "%s: Unable to start governor for the device\n", + __func__); goto err_init; } + create_sysfs_files(devfreq, devfreq->governor); + + list_add(&devfreq->node, &devfreq_list); + + mutex_unlock(&devfreq_list_lock); + + if (devfreq->profile->is_cooling_device) { + devfreq->cdev = devfreq_cooling_em_register(devfreq, NULL); + if (IS_ERR(devfreq->cdev)) + devfreq->cdev = NULL; + } return devfreq; err_init: - list_del(&devfreq->node); - device_unregister(&devfreq->dev); + mutex_unlock(&devfreq_list_lock); +err_devfreq: + devfreq_remove_device(devfreq); + devfreq = NULL; err_dev: kfree(devfreq); err_out: @@ -535,12 +993,154 @@ int devfreq_remove_device(struct devfreq *devfreq) if (!devfreq) return -EINVAL; - _remove_devfreq(devfreq, false); + devfreq_cooling_unregister(devfreq->cdev); + + if (devfreq->governor) { + devfreq->governor->event_handler(devfreq, + DEVFREQ_GOV_STOP, NULL); + remove_sysfs_files(devfreq, devfreq->governor); + } + + 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: devfreq driver pass to governors, governor should not change it. + * + * 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_node - Get the devfreq device from devicetree + * @node - pointer to device_node + * + * return the instance of devfreq device + */ +struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node) +{ + struct devfreq *devfreq; + + if (!node) + return ERR_PTR(-EINVAL); + + mutex_lock(&devfreq_list_lock); + list_for_each_entry(devfreq, &devfreq_list, node) { + if (devfreq->dev.parent + && device_match_of_node(devfreq->dev.parent, node)) { + mutex_unlock(&devfreq_list_lock); + return devfreq; + } + } + mutex_unlock(&devfreq_list_lock); + + return ERR_PTR(-ENODEV); +} + +/* + * devfreq_get_devfreq_by_phandle - Get the devfreq device from devicetree + * @dev - instance to the given device + * @phandle_name - name of property holding a phandle value + * @index - index into list of devfreq + * + * return the instance of devfreq device + */ +struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, + const char *phandle_name, int index) +{ + struct device_node *node; + struct devfreq *devfreq; + + if (!dev || !phandle_name) + return ERR_PTR(-EINVAL); + + if (!dev->of_node) + return ERR_PTR(-EINVAL); + + node = of_parse_phandle(dev->of_node, phandle_name, index); + if (!node) + return ERR_PTR(-ENODEV); + + devfreq = devfreq_get_devfreq_by_node(node); + of_node_put(node); + + return devfreq; +} + +#else +struct devfreq *devfreq_get_devfreq_by_node(struct device_node *node) +{ + return ERR_PTR(-ENODEV); +} + +struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, + const char *phandle_name, int index) +{ + return ERR_PTR(-ENODEV); +} +#endif /* CONFIG_OF */ +EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_node); +EXPORT_SYMBOL_GPL(devfreq_get_devfreq_by_phandle); + +/** + * devm_devfreq_remove_device() - Resource-managed devfreq_remove_device() + * @dev: the device from which to remove 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 @@ -551,14 +1151,30 @@ EXPORT_SYMBOL(devfreq_remove_device); */ int devfreq_suspend_device(struct devfreq *devfreq) { + int ret; + if (!devfreq) return -EINVAL; - if (!devfreq->governor) + if (atomic_inc_return(&devfreq->suspend_count) > 1) return 0; - return devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_SUSPEND, NULL); + if (devfreq->governor) { + ret = devfreq->governor->event_handler(devfreq, + DEVFREQ_GOV_SUSPEND, NULL); + if (ret) + return ret; + } + + if (devfreq->suspend_freq) { + mutex_lock(&devfreq->lock); + ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0); + mutex_unlock(&devfreq->lock); + if (ret) + return ret; + } + + return 0; } EXPORT_SYMBOL(devfreq_suspend_device); @@ -572,18 +1188,78 @@ EXPORT_SYMBOL(devfreq_suspend_device); */ int devfreq_resume_device(struct devfreq *devfreq) { + int ret; + if (!devfreq) return -EINVAL; - if (!devfreq->governor) + if (atomic_dec_return(&devfreq->suspend_count) >= 1) return 0; - return devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_RESUME, NULL); + if (devfreq->resume_freq) { + mutex_lock(&devfreq->lock); + ret = devfreq_set_target(devfreq, devfreq->resume_freq, 0); + mutex_unlock(&devfreq->lock); + 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 */ @@ -613,7 +1289,7 @@ int devfreq_add_governor(struct devfreq_governor *governor) int ret = 0; struct device *dev = devfreq->dev.parent; - if (!strncmp(devfreq->governor_name, governor->name, + if (!strncmp(devfreq->governor->name, governor->name, DEVFREQ_NAME_LEN)) { /* The following should never occur */ if (devfreq->governor) { @@ -648,8 +1324,34 @@ err_out: } EXPORT_SYMBOL(devfreq_add_governor); +static void devm_devfreq_remove_governor(void *governor) +{ + WARN_ON(devfreq_remove_governor(governor)); +} + /** - * devfreq_remove_device() - Remove devfreq feature from a device. + * devm_devfreq_add_governor() - Add devfreq governor + * @dev: device which adds devfreq governor + * @governor: the devfreq governor to be added + * + * This is a resource-managed variant of devfreq_add_governor(). + */ +int devm_devfreq_add_governor(struct device *dev, + struct devfreq_governor *governor) +{ + int err; + + err = devfreq_add_governor(governor); + if (err) + return err; + + return devm_add_action_or_reset(dev, devm_devfreq_remove_governor, + governor); +} +EXPORT_SYMBOL(devm_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) @@ -675,15 +1377,11 @@ int devfreq_remove_governor(struct devfreq_governor *governor) int ret; struct device *dev = devfreq->dev.parent; - if (!strncmp(devfreq->governor_name, governor->name, + if (!devfreq->governor) + continue; + + 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) { @@ -703,50 +1401,96 @@ err_out: } EXPORT_SYMBOL(devfreq_remove_governor); -static ssize_t show_governor(struct device *dev, +static ssize_t name_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct devfreq *df = to_devfreq(dev); + return sprintf(buf, "%s\n", dev_name(df->dev.parent)); +} +static DEVICE_ATTR_RO(name); + +static ssize_t governor_show(struct device *dev, struct device_attribute *attr, char *buf) { - if (!to_devfreq(dev)->governor) + struct devfreq *df = to_devfreq(dev); + + if (!df->governor) return -EINVAL; - return sprintf(buf, "%s\n", to_devfreq(dev)->governor->name); + return sprintf(buf, "%s\n", df->governor->name); } -static ssize_t store_governor(struct device *dev, struct device_attribute *attr, +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; + const struct devfreq_governor *governor, *prev_governor; + + if (!df->governor) + return -EINVAL; ret = sscanf(buf, "%" __stringify(DEVFREQ_NAME_LEN) "s", str_governor); if (ret != 1) return -EINVAL; mutex_lock(&devfreq_list_lock); - governor = find_devfreq_governor(str_governor); + governor = try_then_request_governor(str_governor); if (IS_ERR(governor)) { ret = PTR_ERR(governor); goto out; } - if (df->governor == governor) + if (df->governor == governor) { + ret = 0; goto out; + } else if (IS_SUPPORTED_FLAG(df->governor->flags, IMMUTABLE) + || IS_SUPPORTED_FLAG(governor->flags, 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; - } + /* + * Stop the current governor and remove the specific sysfs files + * which depend on current 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; } + remove_sysfs_files(df, df->governor); + + /* + * Start the new governor and create the specific sysfs files + * which depend on the new governor. + */ + prev_governor = df->governor; df->governor = governor; - strncpy(df->governor_name, governor->name, DEVFREQ_NAME_LEN); ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); - if (ret) + if (ret) { dev_warn(dev, "%s: Governor %s not started(%d)\n", __func__, df->governor->name, ret); + + /* Restore previous governor */ + df->governor = prev_governor; + ret = df->governor->event_handler(df, DEVFREQ_GOV_START, NULL); + if (ret) { + dev_err(dev, + "%s: reverting to Governor %s failed (%d)\n", + __func__, prev_governor->name, ret); + df->governor = NULL; + goto out; + } + } + + /* + * Create the sysfs files for the new governor. But if failed to start + * the new governor, restore the sysfs files of previous governor. + */ + create_sysfs_files(df, df->governor); + out: mutex_unlock(&devfreq_list_lock); @@ -754,17 +1498,42 @@ out: ret = count; return ret; } -static ssize_t show_available_governors(struct device *d, - struct device_attribute *attr, - char *buf) +static DEVICE_ATTR_RW(governor); + +static ssize_t available_governors_show(struct device *d, + struct device_attribute *attr, + char *buf) { - struct devfreq_governor *tmp_governor; + struct devfreq *df = to_devfreq(d); ssize_t count = 0; + if (!df->governor) + return -EINVAL; + mutex_lock(&devfreq_list_lock); - list_for_each_entry(tmp_governor, &devfreq_governor_list, node) - count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), - "%s ", tmp_governor->name); + + /* + * The devfreq with immutable governor (e.g., passive) shows + * only own governor. + */ + if (IS_SUPPORTED_FLAG(df->governor->flags, 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 (IS_SUPPORTED_FLAG(governor->flags, IMMUTABLE)) + continue; + count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), + "%s ", governor->name); + } + } + mutex_unlock(&devfreq_list_lock); /* Truncate the trailing space */ @@ -775,141 +1544,147 @@ static ssize_t show_available_governors(struct device *d, return count; } +static DEVICE_ATTR_RO(available_governors); -static ssize_t show_freq(struct device *dev, - struct device_attribute *attr, char *buf) +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); + struct devfreq *df = to_devfreq(dev); - return sprintf(buf, "%lu\n", devfreq->previous_freq); -} + if (!df->profile) + return -EINVAL; -static ssize_t show_target_freq(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sprintf(buf, "%lu\n", to_devfreq(dev)->previous_freq); -} + if (df->profile->get_cur_freq && + !df->profile->get_cur_freq(df->dev.parent, &freq)) + return sprintf(buf, "%lu\n", freq); -static ssize_t show_polling_interval(struct device *dev, - struct device_attribute *attr, char *buf) -{ - return sprintf(buf, "%d\n", to_devfreq(dev)->profile->polling_ms); + return sprintf(buf, "%lu\n", df->previous_freq); } +static DEVICE_ATTR_RO(cur_freq); -static ssize_t store_polling_interval(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) +static ssize_t target_freq_show(struct device *dev, + struct device_attribute *attr, char *buf) { 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; + return sprintf(buf, "%lu\n", df->previous_freq); } +static DEVICE_ATTR_RO(target_freq); -static ssize_t store_min_freq(struct device *dev, struct device_attribute *attr, +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; - unsigned long max; + + /* + * Protect against theoretical sysfs writes between + * device_add and dev_pm_qos_add_request + */ + if (!dev_pm_qos_request_active(&df->user_min_freq_req)) + return -EAGAIN; ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; - mutex_lock(&df->lock); - max = df->max_freq; - if (value && max && value > max) { - ret = -EINVAL; - goto unlock; - } + /* Round down to kHz for PM QoS */ + ret = dev_pm_qos_update_request(&df->user_min_freq_req, + value / HZ_PER_KHZ); + if (ret < 0) + return ret; - df->min_freq = value; - update_devfreq(df); - ret = count; -unlock: - mutex_unlock(&df->lock); - return ret; + return count; } -static ssize_t show_min_freq(struct device *dev, struct device_attribute *attr, +static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%lu\n", to_devfreq(dev)->min_freq); + struct devfreq *df = to_devfreq(dev); + unsigned long min_freq, max_freq; + + mutex_lock(&df->lock); + devfreq_get_freq_range(df, &min_freq, &max_freq); + mutex_unlock(&df->lock); + + return sprintf(buf, "%lu\n", min_freq); } +static DEVICE_ATTR_RW(min_freq); -static ssize_t store_max_freq(struct device *dev, struct device_attribute *attr, +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; - unsigned long min; + + /* + * Protect against theoretical sysfs writes between + * device_add and dev_pm_qos_add_request + */ + if (!dev_pm_qos_request_active(&df->user_max_freq_req)) + return -EINVAL; ret = sscanf(buf, "%lu", &value); if (ret != 1) return -EINVAL; - mutex_lock(&df->lock); - min = df->min_freq; - if (value && min && value < min) { - ret = -EINVAL; - goto unlock; - } + /* + * PM QoS frequencies are in kHz so we need to convert. Convert by + * rounding upwards so that the acceptable interval never shrinks. + * + * For example if the user writes "666666666" to sysfs this value will + * be converted to 666667 kHz and back to 666667000 Hz before an OPP + * lookup, this ensures that an OPP of 666666666Hz is still accepted. + * + * A value of zero means "no limit". + */ + if (value) + value = DIV_ROUND_UP(value, HZ_PER_KHZ); + else + value = PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE; - df->max_freq = value; - update_devfreq(df); - ret = count; -unlock: - mutex_unlock(&df->lock); - return ret; + ret = dev_pm_qos_update_request(&df->user_max_freq_req, value); + if (ret < 0) + return ret; + + return count; } -static ssize_t show_max_freq(struct device *dev, struct device_attribute *attr, +static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr, char *buf) { - return sprintf(buf, "%lu\n", to_devfreq(dev)->max_freq); + struct devfreq *df = to_devfreq(dev); + unsigned long min_freq, max_freq; + + mutex_lock(&df->lock); + devfreq_get_freq_range(df, &min_freq, &max_freq); + mutex_unlock(&df->lock); + + return sprintf(buf, "%lu\n", max_freq); } +static DEVICE_ATTR_RW(max_freq); -static ssize_t show_available_freqs(struct device *d, - struct device_attribute *attr, - char *buf) +static ssize_t available_frequencies_show(struct device *d, + struct device_attribute *attr, + char *buf) { struct devfreq *df = to_devfreq(d); - struct device *dev = df->dev.parent; - struct opp *opp; ssize_t count = 0; - unsigned long freq = 0; + int i; - rcu_read_lock(); - do { - opp = opp_find_freq_ceil(dev, &freq); - if (IS_ERR(opp)) - break; + if (!df->profile) + return -EINVAL; + mutex_lock(&df->lock); + + for (i = 0; i < df->max_state; i++) count += scnprintf(&buf[count], (PAGE_SIZE - count - 2), - "%lu ", freq); - freq++; - } while (1); - rcu_read_unlock(); + "%lu ", df->freq_table[i]); + mutex_unlock(&df->lock); /* Truncate the trailing space */ if (count) count--; @@ -918,91 +1693,357 @@ static ssize_t show_available_freqs(struct device *d, return count; } +static DEVICE_ATTR_RO(available_frequencies); -static ssize_t show_trans_table(struct device *dev, struct device_attribute *attr, - char *buf) +static ssize_t trans_stat_show(struct device *dev, + struct device_attribute *attr, char *buf) { - struct devfreq *devfreq = to_devfreq(dev); - ssize_t len; + struct devfreq *df = to_devfreq(dev); + ssize_t len = 0; int i, j; - unsigned int max_state = devfreq->profile->max_state; + unsigned int max_state; - if (!devfreq->stop_polling && - devfreq_update_status(devfreq, devfreq->previous_freq)) + if (!df->profile) + return -EINVAL; + max_state = df->max_state; + + if (max_state == 0) + return sysfs_emit(buf, "Not Supported.\n"); + + mutex_lock(&df->lock); + if (!df->stop_polling && + devfreq_update_status(df, df->previous_freq)) { + mutex_unlock(&df->lock); return 0; + } + mutex_unlock(&df->lock); - len = sprintf(buf, " From : To\n"); - len += sprintf(buf + len, " :"); - for (i = 0; i < max_state; i++) - len += sprintf(buf + len, "%8u", - devfreq->profile->freq_table[i]); + len += sysfs_emit_at(buf, len, " From : To\n"); + len += sysfs_emit_at(buf, len, " :"); + for (i = 0; i < max_state; i++) { + if (len >= PAGE_SIZE - 1) + break; + len += sysfs_emit_at(buf, len, "%10lu", + df->freq_table[i]); + } - len += sprintf(buf + len, " time(ms)\n"); + if (len >= PAGE_SIZE - 1) + return PAGE_SIZE - 1; + len += sysfs_emit_at(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, " "); + if (len >= PAGE_SIZE - 1) + break; + if (df->freq_table[i] == df->previous_freq) + len += sysfs_emit_at(buf, len, "*"); + else + len += sysfs_emit_at(buf, len, " "); + if (len >= PAGE_SIZE - 1) + break; + len += sysfs_emit_at(buf, len, "%10lu:", df->freq_table[i]); + for (j = 0; j < max_state; j++) { + if (len >= PAGE_SIZE - 1) + break; + len += sysfs_emit_at(buf, len, "%10u", + df->stats.trans_table[(i * max_state) + j]); } - len += sprintf(buf + len, "%8u:", - devfreq->profile->freq_table[i]); - for (j = 0; j < max_state; j++) - len += sprintf(buf + len, "%8u", - devfreq->trans_table[(i * max_state) + j]); - len += sprintf(buf + len, "%10u\n", - jiffies_to_msecs(devfreq->time_in_state[i])); + if (len >= PAGE_SIZE - 1) + break; + len += sysfs_emit_at(buf, len, "%10llu\n", (u64) + jiffies64_to_msecs(df->stats.time_in_state[i])); + } + + if (len < PAGE_SIZE - 1) + len += sysfs_emit_at(buf, len, "Total transition : %u\n", + df->stats.total_trans); + if (len >= PAGE_SIZE - 1) { + pr_warn_once("devfreq transition table exceeds PAGE_SIZE. Disabling\n"); + return -EFBIG; } - len += sprintf(buf + len, "Total transition : %u\n", - devfreq->total_trans); return len; } -static struct device_attribute devfreq_attrs[] = { - __ATTR(governor, S_IRUGO | S_IWUSR, show_governor, store_governor), - __ATTR(available_governors, S_IRUGO, show_available_governors, NULL), - __ATTR(cur_freq, S_IRUGO, show_freq, NULL), - __ATTR(available_frequencies, S_IRUGO, show_available_freqs, NULL), - __ATTR(target_freq, S_IRUGO, show_target_freq, NULL), - __ATTR(polling_interval, S_IRUGO | S_IWUSR, show_polling_interval, - store_polling_interval), - __ATTR(min_freq, S_IRUGO | S_IWUSR, show_min_freq, store_min_freq), - __ATTR(max_freq, S_IRUGO | S_IWUSR, show_max_freq, store_max_freq), - __ATTR(trans_stat, S_IRUGO, show_trans_table, NULL), - { }, +static ssize_t trans_stat_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct devfreq *df = to_devfreq(dev); + int err, value; + + if (!df->profile) + return -EINVAL; + + if (df->max_state == 0) + return count; + + err = kstrtoint(buf, 10, &value); + if (err || value != 0) + return -EINVAL; + + mutex_lock(&df->lock); + memset(df->stats.time_in_state, 0, (df->max_state * + sizeof(*df->stats.time_in_state))); + memset(df->stats.trans_table, 0, array3_size(sizeof(unsigned int), + df->max_state, + df->max_state)); + df->stats.total_trans = 0; + df->stats.last_update = get_jiffies_64(); + mutex_unlock(&df->lock); + + return count; +} +static DEVICE_ATTR_RW(trans_stat); + +static struct attribute *devfreq_attrs[] = { + &dev_attr_name.attr, + &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_min_freq.attr, + &dev_attr_max_freq.attr, + &dev_attr_trans_stat.attr, + NULL, }; +ATTRIBUTE_GROUPS(devfreq); + +static ssize_t polling_interval_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct devfreq *df = to_devfreq(dev); + + if (!df->profile) + return -EINVAL; + + return sprintf(buf, "%d\n", df->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_UPDATE_INTERVAL, &value); + ret = count; + + return ret; +} +static DEVICE_ATTR_RW(polling_interval); + +static ssize_t timer_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct devfreq *df = to_devfreq(dev); + + if (!df->profile) + return -EINVAL; + + return sprintf(buf, "%s\n", timer_name[df->profile->timer]); +} + +static ssize_t timer_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct devfreq *df = to_devfreq(dev); + char str_timer[DEVFREQ_NAME_LEN + 1]; + int timer = -1; + int ret = 0, i; + + if (!df->governor || !df->profile) + return -EINVAL; + + ret = sscanf(buf, "%16s", str_timer); + if (ret != 1) + return -EINVAL; + + for (i = 0; i < DEVFREQ_TIMER_NUM; i++) { + if (!strncmp(timer_name[i], str_timer, DEVFREQ_NAME_LEN)) { + timer = i; + break; + } + } + + if (timer < 0) { + ret = -EINVAL; + goto out; + } + + if (df->profile->timer == timer) { + ret = 0; + goto out; + } + + mutex_lock(&df->lock); + df->profile->timer = timer; + mutex_unlock(&df->lock); + + 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; + } + + 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: + return ret ? ret : count; +} +static DEVICE_ATTR_RW(timer); + +#define CREATE_SYSFS_FILE(df, name) \ +{ \ + int ret; \ + ret = sysfs_create_file(&df->dev.kobj, &dev_attr_##name.attr); \ + if (ret < 0) { \ + dev_warn(&df->dev, \ + "Unable to create attr(%s)\n", "##name"); \ + } \ +} \ + +/* Create the specific sysfs files which depend on each governor. */ +static void create_sysfs_files(struct devfreq *devfreq, + const struct devfreq_governor *gov) +{ + if (IS_SUPPORTED_ATTR(gov->attrs, POLLING_INTERVAL)) + CREATE_SYSFS_FILE(devfreq, polling_interval); + if (IS_SUPPORTED_ATTR(gov->attrs, TIMER)) + CREATE_SYSFS_FILE(devfreq, timer); +} + +/* Remove the specific sysfs files which depend on each governor. */ +static void remove_sysfs_files(struct devfreq *devfreq, + const struct devfreq_governor *gov) +{ + if (IS_SUPPORTED_ATTR(gov->attrs, POLLING_INTERVAL)) + sysfs_remove_file(&devfreq->dev.kobj, + &dev_attr_polling_interval.attr); + if (IS_SUPPORTED_ATTR(gov->attrs, TIMER)) + sysfs_remove_file(&devfreq->dev.kobj, &dev_attr_timer.attr); +} + +/** + * devfreq_summary_show() - Show the summary of the devfreq devices + * @s: seq_file instance to show the summary of devfreq devices + * @data: not used + * + * Show the summary of the devfreq devices via 'devfreq_summary' debugfs file. + * It helps that user can know the detailed information of the devfreq devices. + * + * Return 0 always because it shows the information without any data change. + */ +static int devfreq_summary_show(struct seq_file *s, void *data) +{ + struct devfreq *devfreq; + struct devfreq *p_devfreq = NULL; + unsigned long cur_freq, min_freq, max_freq; + unsigned int polling_ms; + unsigned int timer; + + seq_printf(s, "%-30s %-30s %-15s %-10s %10s %12s %12s %12s\n", + "dev", + "parent_dev", + "governor", + "timer", + "polling_ms", + "cur_freq_Hz", + "min_freq_Hz", + "max_freq_Hz"); + seq_printf(s, "%30s %30s %15s %10s %10s %12s %12s %12s\n", + "------------------------------", + "------------------------------", + "---------------", + "----------", + "----------", + "------------", + "------------", + "------------"); + + mutex_lock(&devfreq_list_lock); + + list_for_each_entry_reverse(devfreq, &devfreq_list, node) { +#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE) + if (!strncmp(devfreq->governor->name, DEVFREQ_GOV_PASSIVE, + DEVFREQ_NAME_LEN)) { + struct devfreq_passive_data *data = devfreq->data; + + if (data) + p_devfreq = data->parent; + } else { + p_devfreq = NULL; + } +#endif + + mutex_lock(&devfreq->lock); + cur_freq = devfreq->previous_freq; + devfreq_get_freq_range(devfreq, &min_freq, &max_freq); + timer = devfreq->profile->timer; + + if (IS_SUPPORTED_ATTR(devfreq->governor->attrs, POLLING_INTERVAL)) + polling_ms = devfreq->profile->polling_ms; + else + polling_ms = 0; + mutex_unlock(&devfreq->lock); + + seq_printf(s, + "%-30s %-30s %-15s %-10s %10d %12ld %12ld %12ld\n", + dev_name(&devfreq->dev), + p_devfreq ? dev_name(&p_devfreq->dev) : "null", + devfreq->governor->name, + polling_ms ? timer_name[timer] : "null", + polling_ms, + cur_freq, + min_freq, + max_freq); + } + + mutex_unlock(&devfreq_list_lock); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(devfreq_summary); static int __init devfreq_init(void) { - devfreq_class = class_create(THIS_MODULE, "devfreq"); + devfreq_class = class_create("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 (IS_ERR(devfreq_wq)) { + if (!devfreq_wq) { class_destroy(devfreq_class); pr_err("%s: couldn't create workqueue\n", __FILE__); - return PTR_ERR(devfreq_wq); + return -ENOMEM; } - devfreq_class->dev_attrs = devfreq_attrs; + devfreq_class->dev_groups = devfreq_groups; + + devfreq_debugfs = debugfs_create_dir("devfreq", NULL); + debugfs_create_file("devfreq_summary", 0444, + devfreq_debugfs, NULL, + &devfreq_summary_fops); return 0; } subsys_initcall(devfreq_init); -static void __exit devfreq_exit(void) -{ - class_destroy(devfreq_class); - destroy_workqueue(devfreq_wq); -} -module_exit(devfreq_exit); - /* - * The followings are helper functions for devfreq user device drivers with + * The following are helper functions for devfreq user device drivers with * OPP framework. */ @@ -1013,63 +2054,52 @@ module_exit(devfreq_exit); * @freq: The frequency given to target function * @flags: Flags handed from devfreq framework. * - * Locking: This function must be called under rcu_read_lock(). opp is a rcu - * protected pointer. The reason for the same is that the opp pointer which is - * returned will remain valid for use with opp_get_{voltage, freq} only while - * under the locked area. The pointer returned must be used prior to unlocking - * with rcu_read_unlock() to maintain the integrity of the pointer. + * The callers are required to call dev_pm_opp_put() for the returned OPP after + * use. */ -struct opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq, - u32 flags) +struct dev_pm_opp *devfreq_recommended_opp(struct device *dev, + unsigned long *freq, + u32 flags) { - struct opp *opp; + struct dev_pm_opp *opp; if (flags & DEVFREQ_FLAG_LEAST_UPPER_BOUND) { /* The freq is an upper bound. opp should be lower */ - opp = opp_find_freq_floor(dev, freq); + opp = dev_pm_opp_find_freq_floor_indexed(dev, freq, 0); /* If not available, use the closest opp */ if (opp == ERR_PTR(-ERANGE)) - opp = opp_find_freq_ceil(dev, freq); + opp = dev_pm_opp_find_freq_ceil_indexed(dev, freq, 0); } else { /* The freq is an lower bound. opp should be higher */ - opp = opp_find_freq_ceil(dev, freq); + opp = dev_pm_opp_find_freq_ceil_indexed(dev, freq, 0); /* If not available, use the closest opp */ if (opp == ERR_PTR(-ERANGE)) - opp = opp_find_freq_floor(dev, freq); + opp = dev_pm_opp_find_freq_floor_indexed(dev, freq, 0); } 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 + * 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) { - struct srcu_notifier_head *nh; - int ret = 0; - - rcu_read_lock(); - nh = opp_get_notifier(dev); - if (IS_ERR(nh)) - ret = PTR_ERR(nh); - rcu_read_unlock(); - if (!ret) - ret = srcu_notifier_chain_register(nh, &devfreq->nb); - - return ret; + 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. + * notified for any changes in the OPP + * availability changes anymore. * @dev: The devfreq user device. (parent of devfreq) * @devfreq: The devfreq object. * @@ -1078,20 +2108,177 @@ int devfreq_register_opp_notifier(struct device *dev, struct devfreq *devfreq) */ int devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq) { - struct srcu_notifier_head *nh; + 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; - rcu_read_lock(); - nh = opp_get_notifier(dev); - if (IS_ERR(nh)) - ret = PTR_ERR(nh); - rcu_read_unlock(); - if (!ret) - ret = srcu_notifier_chain_unregister(nh, &devfreq->nb); + 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; +}; -MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); -MODULE_DESCRIPTION("devfreq class support"); -MODULE_LICENSE("GPL"); +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); |