Instead of devfreq device driver explicitly calling devfreq suspend and resume apis perhaps from runtime-pm suspend and resume callbacks, let devfreq core handle it automatically.

Attach devfreq core to runtime-pm framework so that, devfreq device driver pm_runtime_suspend() will automatically suspend the devfreq and pm_runtime_resume() will resume the devfreq.

Signed-off-by: Rajagopal Venkat rajagopal.venkat@linaro.org --- drivers/devfreq/devfreq.c | 145 ++++++++++++++++++++++++++++++++-------------- include/linux/devfreq.h | 12 ---- 2 files changed, 102 insertions(+), 55 deletions(-)

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 45e053e..190e414 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -25,10 +25,9 @@ #include <linux/list.h> #include <linux/printk.h> #include <linux/hrtimer.h> +#include <linux/pm_runtime.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 @@ -414,6 +413,93 @@ static void devfreq_dev_release(struct device *dev) }

/** + * devfreq_suspend_device() - Suspend devfreq of a device. + * @devfreq: the devfreq instance to be suspended + */ +static int devfreq_suspend_device(struct devfreq *devfreq) +{ + if (!devfreq) + return -EINVAL; + + if (!devfreq->governor) + return 0; + + return devfreq->governor->event_handler(devfreq, + DEVFREQ_GOV_SUSPEND, NULL); +} + +/** + * devfreq_resume_device() - Resume devfreq of a device. + * @devfreq: the devfreq instance to be resumed + */ +static int devfreq_resume_device(struct devfreq *devfreq) +{ + if (!devfreq) + return -EINVAL; + + if (!devfreq->governor) + return 0; + + return devfreq->governor->event_handler(devfreq, + DEVFREQ_GOV_RESUME, NULL); +} + +static int devfreq_runtime_suspend(struct device *dev) +{ + int ret; + struct devfreq *devfreq; + + mutex_lock(&devfreq_list_lock); + devfreq = find_device_devfreq(dev); + mutex_unlock(&devfreq_list_lock); + + ret = devfreq_suspend_device(devfreq); + if (ret < 0) + goto out; + + ret = pm_generic_runtime_suspend(dev); +out: + return ret; +} + +static int devfreq_runtime_resume(struct device *dev) +{ + int ret; + struct devfreq *devfreq; + + mutex_lock(&devfreq_list_lock); + devfreq = find_device_devfreq(dev); + mutex_unlock(&devfreq_list_lock); + + ret = devfreq_resume_device(devfreq); + if (ret < 0) + goto out; + + ret = pm_generic_runtime_resume(dev); +out: + return ret; +} + +static int devfreq_runtime_idle(struct device *dev) +{ + return pm_generic_runtime_idle(dev); +} + +static const struct dev_pm_ops devfreq_pm_ops = { + SET_RUNTIME_PM_OPS( + devfreq_runtime_suspend, + devfreq_runtime_resume, + devfreq_runtime_idle + ) +}; + +static struct class devfreq_class = { + .name = "devfreq", + .owner = THIS_MODULE, + .pm = &devfreq_pm_ops, +}; + +/** * devfreq_add_device() - Add devfreq feature to the device * @dev: the device to add devfreq feature. * @profile: device-specific profile to run devfreq. @@ -454,8 +540,9 @@ struct devfreq *devfreq_add_device(struct device *dev,

mutex_init(&devfreq->lock); mutex_lock(&devfreq->lock); + dev->class = &devfreq_class; devfreq->dev.parent = dev; - devfreq->dev.class = devfreq_class; + devfreq->dev.class = &devfreq_class; devfreq->dev.release = devfreq_dev_release; devfreq->profile = profile; strncpy(devfreq->governor_name, governor_name, DEVFREQ_NAME_LEN); @@ -498,6 +585,9 @@ struct devfreq *devfreq_add_device(struct device *dev, goto err_init; }

+ pm_runtime_get_noresume(dev); + pm_runtime_set_active(dev); + return devfreq;

err_init: @@ -526,40 +616,6 @@ int devfreq_remove_device(struct devfreq *devfreq) EXPORT_SYMBOL(devfreq_remove_device);

/** - * devfreq_suspend_device() - Suspend devfreq of a device. - * @devfreq: the devfreq instance to be suspended - */ -int devfreq_suspend_device(struct devfreq *devfreq) -{ - if (!devfreq) - return -EINVAL; - - if (!devfreq->governor) - return 0; - - return devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_SUSPEND, NULL); -} -EXPORT_SYMBOL(devfreq_suspend_device); - -/** - * devfreq_resume_device() - Resume devfreq of a device. - * @devfreq: the devfreq instance to be resumed - */ -int devfreq_resume_device(struct devfreq *devfreq) -{ - if (!devfreq) - return -EINVAL; - - if (!devfreq->governor) - return 0; - - return devfreq->governor->event_handler(devfreq, - DEVFREQ_GOV_RESUME, NULL); -} -EXPORT_SYMBOL(devfreq_resume_device); - -/** * devfreq_add_governor() - Add devfreq governor * @governor: the devfreq governor to be added */ @@ -730,6 +786,7 @@ out: ret = count; return ret; } + static ssize_t show_available_governors(struct device *d, struct device_attribute *attr, char *buf) @@ -952,19 +1009,21 @@ static struct device_attribute devfreq_attrs[] = {

static int __init devfreq_init(void) { - devfreq_class = class_create(THIS_MODULE, "devfreq"); - if (IS_ERR(devfreq_class)) { + int err; + + err = class_register(&devfreq_class); + if (err < 0) { pr_err("%s: couldn't create class\n", __FILE__); - return PTR_ERR(devfreq_class); + return err; }

devfreq_wq = create_freezable_workqueue("devfreq_wq"); if (IS_ERR(devfreq_wq)) { - class_destroy(devfreq_class); + class_unregister(&devfreq_class); pr_err("%s: couldn't create workqueue\n", __FILE__); return PTR_ERR(devfreq_wq); } - devfreq_class->dev_attrs = devfreq_attrs; + devfreq_class.dev_attrs = devfreq_attrs;

return 0; } @@ -972,7 +1031,7 @@ subsys_initcall(devfreq_init);

static void __exit devfreq_exit(void) { - class_destroy(devfreq_class); + class_unregister(&devfreq_class); destroy_workqueue(devfreq_wq); } module_exit(devfreq_exit); diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h index 235248c..4fd920f 100644 --- a/include/linux/devfreq.h +++ b/include/linux/devfreq.h @@ -181,8 +181,6 @@ extern struct devfreq *devfreq_add_device(struct device *dev, const char *governor_name, void *data); extern int devfreq_remove_device(struct devfreq *devfreq); -extern int devfreq_suspend_device(struct devfreq *devfreq); -extern int devfreq_resume_device(struct devfreq *devfreq);

/* Helper functions for devfreq user device driver with OPP. */ extern struct opp *devfreq_recommended_opp(struct device *dev, @@ -226,16 +224,6 @@ static int devfreq_remove_device(struct devfreq *devfreq) return 0; }

-static int devfreq_suspend_device(struct devfreq *devfreq) -{ - return 0; -} - -static int devfreq_resume_device(struct devfreq *devfreq) -{ - return 0; -} - static struct opp *devfreq_recommended_opp(struct device *dev, unsigned long *freq, u32 flags) {