Re: [PATCH 1/1] thermal: fix cpu_cooling max_level behavior
From: Eduardo Valentin
Date: Fri Dec 06 2013 - 08:52:59 EST
On 13-11-2013 14:11, Eduardo Valentin wrote:
> As per Documentation/thermal/sysfs-api.txt, max_level
> is an index, not a counter. Thus, in case a CPU has
> 3 valid frequencies, max_level is expected to be 2, for instance.
>
> The current code makes max_level == number of valid frequencies,
> which is bogus. This patch fix the cpu_cooling device by
> ranging max_level properly.
>
> Reported-by: Carlos Hernandez <ceh@xxxxxx>
> Signed-off-by: Eduardo Valentin <eduardo.valentin@xxxxxx>
Rui,
Can you please consider pushing this fix?
> ---
> drivers/thermal/cpu_cooling.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
> index d179028..d0f8f8b5 100644
> --- a/drivers/thermal/cpu_cooling.c
> +++ b/drivers/thermal/cpu_cooling.c
> @@ -173,6 +173,8 @@ static int get_property(unsigned int cpu, unsigned long input,
> freq = table[i].frequency;
> max_level++;
> }
> + /* max_level is an index, not a counter */
> + max_level--;
>
> /* get max level */
> if (property == GET_MAXL) {
> @@ -181,7 +183,7 @@ static int get_property(unsigned int cpu, unsigned long input,
> }
>
> if (property == GET_FREQ)
> - level = descend ? input : (max_level - input - 1);
> + level = descend ? input : (max_level - input);
>
> for (i = 0, j = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
> /* ignore invalid entry */
> @@ -197,7 +199,7 @@ static int get_property(unsigned int cpu, unsigned long input,
>
> if (property == GET_LEVEL && (unsigned int)input == freq) {
> /* get level by frequency */
> - *output = descend ? j : (max_level - j - 1);
> + *output = descend ? j : (max_level - j);
> return 0;
> }
> if (property == GET_FREQ && level == j) {
>
--
You have got to be excited about what you are doing. (L. Lamport)
Eduardo Valentin
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