diff options
Diffstat (limited to 'drivers/devfreq/devfreq.c')
| -rw-r--r-- | drivers/devfreq/devfreq.c | 207 |
1 files changed, 206 insertions, 1 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 984c5e9e7bdd..1d6c803804d5 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -25,6 +25,7 @@ #include <linux/list.h> #include <linux/printk.h> #include <linux/hrtimer.h> +#include <linux/of.h> #include "governor.h" static struct class *devfreq_class; @@ -188,6 +189,29 @@ static struct devfreq_governor *find_devfreq_governor(const char *name) return ERR_PTR(-ENODEV); } +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; +} + /* Load monitoring helper functions for governors use */ /** @@ -199,7 +223,8 @@ static struct devfreq_governor *find_devfreq_governor(const char *name) */ int update_devfreq(struct devfreq *devfreq) { - unsigned long freq; + struct devfreq_freqs freqs; + unsigned long freq, cur_freq; int err = 0; u32 flags = 0; @@ -233,10 +258,22 @@ int update_devfreq(struct devfreq *devfreq) flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */ } + 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 = freq; + devfreq_notify_transition(devfreq, &freqs, DEVFREQ_PRECHANGE); + err = devfreq->profile->target(devfreq->dev.parent, &freq, flags); if (err) return err; + freqs.new = freq; + devfreq_notify_transition(devfreq, &freqs, DEVFREQ_POSTCHANGE); + if (devfreq->profile->freq_table) if (devfreq_update_status(devfreq, freq)) dev_err(&devfreq->dev, @@ -541,6 +578,8 @@ struct devfreq *devfreq_add_device(struct device *dev, goto err_out; } + srcu_init_notifier_head(&devfreq->transition_notifier_list); + mutex_unlock(&devfreq->lock); mutex_lock(&devfreq_list_lock); @@ -639,6 +678,49 @@ struct devfreq *devm_devfreq_add_device(struct device *dev, } 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); + return devfreq; + } + } + mutex_unlock(&devfreq_list_lock); + + 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. @@ -1266,6 +1348,129 @@ void devm_devfreq_unregister_opp_notifier(struct device *dev, } 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); + MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); MODULE_DESCRIPTION("devfreq class support"); MODULE_LICENSE("GPL"); |