Hi,

Please resend the patch with related other patches.
It is hard to check the dependency/sequence of your patches.

On 2018년 05월 18일 07:32, Matthias Kaehlcke wrote:
> Commit ab8f58ad72c4 ("PM / devfreq: Set min/max_freq when adding the
> devfreq device") initializes df->min/max_freq with the min/max OPP when
> the device is added. Later commit f1d981eaecf8 ("PM / devfreq: Use the
> available min/max frequency") adds df->scaling_min/max_freq and the
> following to the frequency adjustment code:
> 
>   max_freq = MIN(devfreq->scaling_max_freq, devfreq->max_freq);
> 
> With the current handling of min/max_freq this is incorrect:
> 
> Even though df->max_freq is now initialized to a value != 0 user space
> can still set it to 0, in this case max_freq would be 0 instead of
> df->scaling_max_freq as intended. In consequence the frequency adjustment
> is not performed:
> 
>   if (max_freq && freq > max_freq) {
>       freq = max_freq;
> 
> To fix this set df->min/max freq to the min/max OPP in max/max_freq_store,
> when the user passes a value of 0. This also prevents df->max_freq from
> being set below the min OPP when df->min_freq is 0, and similar for
> min_freq. Since it is now guaranteed that df->min/max_freq can't be 0 the
> checks for this case can be removed.
> 
> Fixes: f1d981eaecf8 ("PM / devfreq: Use the available min/max frequency")
> Signed-off-by: Matthias Kaehlcke <m...@chromium.org>
> ---
>  drivers/devfreq/devfreq.c | 30 ++++++++++++++++++------------
>  1 file changed, 18 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index fe2af6aa88fc..e007534297f7 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -283,11 +283,11 @@ int update_devfreq(struct devfreq *devfreq)
>       max_freq = MIN(devfreq->scaling_max_freq, devfreq->max_freq);
>       min_freq = MAX(devfreq->scaling_min_freq, devfreq->min_freq);
>  
> -     if (min_freq && freq < min_freq) {
> +     if (freq < min_freq) {
>               freq = min_freq;
>               flags &= ~DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use GLB */
>       }
> -     if (max_freq && freq > max_freq) {
> +     if (freq > max_freq) {
>               freq = max_freq;
>               flags |= DEVFREQ_FLAG_LEAST_UPPER_BOUND; /* Use LUB */
>       }
> @@ -1123,17 +1123,20 @@ static ssize_t min_freq_store(struct device *dev, 
> struct device_attribute *attr,
>       struct devfreq *df = to_devfreq(dev);
>       unsigned long value;
>       int ret;
> -     unsigned long max;
>  
>       ret = sscanf(buf, "%lu", &value);
>       if (ret != 1)
>               return -EINVAL;
>  
>       mutex_lock(&df->lock);
> -     max = df->max_freq;
> -     if (value && max && value > max) {
> -             ret = -EINVAL;
> -             goto unlock;
> +
> +     if (value) {
> +             if (value > df->max_freq) {
> +                     ret = -EINVAL;
> +                     goto unlock;
> +             }
> +     } else {
> +             value = df->profile->freq_table[df->profile->max_state - 1];
>       }
>  
>       df->min_freq = value;
> @@ -1158,17 +1161,20 @@ static ssize_t max_freq_store(struct device *dev, 
> struct device_attribute *attr,
>       struct devfreq *df = to_devfreq(dev);
>       unsigned long value;
>       int ret;
> -     unsigned long min;
>  
>       ret = sscanf(buf, "%lu", &value);
>       if (ret != 1)
>               return -EINVAL;
>  
>       mutex_lock(&df->lock);
> -     min = df->min_freq;
> -     if (value && min && value < min) {
> -             ret = -EINVAL;
> -             goto unlock;
> +
> +     if (!value) {
> +             value = df->profile->freq_table[0];
> +     } else {
> +             if (value < df->min_freq) {
> +                     ret = -EINVAL;
> +                     goto unlock;
> +             }
>       }
>  
>       df->max_freq = value;
> 


-- 
Best Regards,
Chanwoo Choi
Samsung Electronics

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