From: Eduardo Valentin eduardo.valentin@ti.com
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@ti.com Signed-off-by: Eduardo Valentin eduardo.valentin@ti.com Signed-off-by: Zhang Rui rui.zhang@intel.com (cherry picked from commit 1c9573a40c1d34494419f32560f28c763c504d79) Signed-off-by: Alex Shi alex.shi@linaro.org --- 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 6093862..3331b1a 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) {