Hi Lukasz, Looks good to me. But, I add the some comments. If you will fix it, feel free to add my tag: Reviewed-by: Chanwoo choi <[email protected]>
On 2018년 12월 03일 23:31, Lukasz Luba wrote: > The patch prepares devfreq device for handling suspend/resume > functionality. The new fields will store needed information during this nitpick. Remove unneeded space. There are two spaces between '.' and 'The new'. > process. Devfreq framework handles opp-suspend DT entry and there is no ditto. > need of modyfications in the drivers code. It uses atomic variables to ditto. > make sure no race condition affects the process. > > The patch is based on earlier work by Tobias Jakobi. Please remove it from each patch description. > > Suggested-by: Tobias Jakobi <[email protected]> > Suggested-by: Chanwoo Choi <[email protected]> > Signed-off-by: Lukasz Luba <[email protected]> > --- > drivers/devfreq/devfreq.c | 51 > +++++++++++++++++++++++++++++++++++++++-------- > include/linux/devfreq.h | 7 +++++++ > 2 files changed, 50 insertions(+), 8 deletions(-) > > diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > index a9fd61b..36bed24 100644 > --- a/drivers/devfreq/devfreq.c > +++ b/drivers/devfreq/devfreq.c > @@ -316,6 +316,10 @@ static int devfreq_set_target(struct devfreq *devfreq, > unsigned long new_freq, > "Couldn't update frequency transition information.\n"); > > devfreq->previous_freq = new_freq; > + > + if (devfreq->suspend_freq) > + devfreq->resume_freq = cur_freq; > + > return err; > } > > @@ -667,6 +671,9 @@ struct devfreq *devfreq_add_device(struct device *dev, > } > devfreq->max_freq = devfreq->scaling_max_freq; > > + devfreq->suspend_freq = dev_pm_opp_get_suspend_opp_freq(dev); > + atomic_set(&devfreq->suspend_count, 0); > + > dev_set_name(&devfreq->dev, "devfreq%d", > atomic_inc_return(&devfreq_no)); > err = device_register(&devfreq->dev); > @@ -867,14 +874,28 @@ EXPORT_SYMBOL(devm_devfreq_remove_device); > */ > int devfreq_suspend_device(struct devfreq *devfreq) > { > + int ret; > + > if (!devfreq) > return -EINVAL; > > - if (!devfreq->governor) > - return 0; > + if (devfreq->governor) { > + ret = devfreq->governor->event_handler(devfreq, > + DEVFREQ_GOV_SUSPEND, NULL); > + if (ret) > + return ret; > + } > + > + if (devfreq->suspend_freq) { > + if (atomic_inc_return(&devfreq->suspend_count) > 1) > + return 0; > + > + ret = devfreq_set_target(devfreq, devfreq->suspend_freq, 0); > + if (ret) > + return ret; > + } > > - return devfreq->governor->event_handler(devfreq, > - DEVFREQ_GOV_SUSPEND, NULL); > + return 0; > } > EXPORT_SYMBOL(devfreq_suspend_device); > > @@ -888,14 +909,28 @@ EXPORT_SYMBOL(devfreq_suspend_device); > */ > int devfreq_resume_device(struct devfreq *devfreq) > { > + int ret; > + > if (!devfreq) > return -EINVAL; > > - if (!devfreq->governor) > - return 0; > + if (devfreq->resume_freq) { > + if (atomic_dec_return(&devfreq->suspend_count) >= 1) > + return 0; > > - return devfreq->governor->event_handler(devfreq, > - DEVFREQ_GOV_RESUME, NULL); > + ret = devfreq_set_target(devfreq, devfreq->resume_freq, 0); > + 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); > > diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h > index e4963b0..d985199 100644 > --- a/include/linux/devfreq.h > +++ b/include/linux/devfreq.h > @@ -131,6 +131,9 @@ struct devfreq_dev_profile { > * @scaling_min_freq: Limit minimum frequency requested by OPP > interface > * @scaling_max_freq: Limit maximum frequency requested by OPP > interface > * @stop_polling: devfreq polling status of a device. > + * @suspend_freq: frequency of a device set during suspend phase. > + * @resume_freq: frequency of a device set in resume phase. > + * @suspend_count: suspend requests counter for a device. > * @total_trans: Number of devfreq transitions > * @trans_table: Statistics of devfreq transitions > * @time_in_state: Statistics of devfreq states > @@ -167,6 +170,10 @@ struct devfreq { > unsigned long scaling_max_freq; > bool stop_polling; > > + unsigned long suspend_freq; > + unsigned long resume_freq; > + atomic_t suspend_count; > + > /* information for device frequency transition */ > unsigned int total_trans; > unsigned int *trans_table; > -- Best Regards, Chanwoo Choi Samsung Electronics
