diff options
Diffstat (limited to 'drivers/devfreq/devfreq.c')
| -rw-r--r-- | drivers/devfreq/devfreq.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 984c5e9e7bdd..20a9422c2552 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; @@ -639,6 +640,49 @@ 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. |