This patch adds the new devfreq_get_devfreq_by_phandle() OF helper function which can find the instance of devfreq device by using phandle ("devfreq"). Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx> [linux.amoon: Tested on Odroid U3] Tested-by: Anand Moon <linux.amoon@xxxxxxxxx> --- drivers/devfreq/devfreq.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/devfreq.h | 9 +++++++++ 2 files changed, 53 insertions(+) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 15e58779e4c0..78ea4cdaa82c 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; @@ -686,6 +687,49 @@ 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. diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 95c54578a1b4..cf972befca2b 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -211,6 +211,9 @@ extern int devm_devfreq_register_opp_notifier(struct device *dev, extern void devm_devfreq_unregister_opp_notifier(struct device *dev, struct devfreq *devfreq); +extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, + int index); + /** * devfreq_update_stats() - update the last_status pointer in struct devfreq * @df: the devfreq instance whose status needs updating @@ -322,6 +325,12 @@ static inline void devm_devfreq_unregister_opp_notifier(struct device *dev, { } +static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev, + int index) +{ + return ERR_PTR(-ENODEV); +} + static inline int devfreq_update_stats(struct devfreq *df) { return -EINVAL; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html