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    SubjectRE: [PATCH 02/11] PM / devfreq: Fix handling of min/max_freq == 0
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    > 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 <mka@chromium.org>
    > ---
    > drivers/devfreq/devfreq.c | 30 ++++++++++++++++++------------
    > 1 file changed, 18 insertions(+), 12 deletions(-)

    Thanks a lot! Nice Catch.

    Acked-by: MyungJoo Ham <myunngjoo.ham@samsung.com>

    Cheers,
    MyungJoo.

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