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SubjectRe: [PATCH] PM: Devfreq: fix userspace governor frequency bug
> The frequency set by userspace governor may not the
> same as the final frequency. If this condition happens,
> then "cat set_freq" will return a wrong value which is
> inconsistant with the real frequency.
>
> This patch updates data->user_frequency after calling
> of update_devfreq. use devfreq->revious_freq as the
> final user_frequency.
>
> Signed-off-by: Xiaoguang Chen <chenxg@marvell.com>

No, this is not a bug.

---- quoting Documentation/ABI/testing/sysfs-class-devfreq ----
What: /sys/class/devfreq/.../userspace/set_freq
Date: September 2011
Contact: MyungJoo Ham <myungjoo.ham@samsung.com>
Description:
The /sys/class/devfreq/.../userspace/set_freq shows and
sets the requested frequency for the devfreq object if
userspace governor is in effect.
---- quote ended ----

set_freq shows the requested frequency, not the actual frequency value.

If you want to see the actual current frequency intended by devfreq,
use "cur_freq".



Cheers!
MyungJoo


> ---
> drivers/devfreq/governor_userspace.c | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/devfreq/governor_userspace.c b/drivers/devfreq/governor_userspace.c
> index 0681246..85ad80a 100644
> --- a/drivers/devfreq/governor_userspace.c
> +++ b/drivers/devfreq/governor_userspace.c
> @@ -59,6 +59,7 @@ static ssize_t store_freq(struct device *dev, struct device_attribute *attr,
> err = update_devfreq(devfreq);
> if (err == 0)
> err = count;
> + data->user_frequency = devfreq->previous_freq;
> mutex_unlock(&devfreq->lock);
> return err;
> }
> --
> 1.7.0.4
>
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