thermal: cpu_cooling: Add comment to clarify relation between cooling state and frequency
This wasn't explained well anywhere and should be clearly specified. Lets add a
top level comment for this.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index cc10641..a5a9317 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -28,6 +28,20 @@
#include <linux/cpu.h>
#include <linux/cpu_cooling.h>
+/*
+ * Cooling state <-> CPUFreq frequency
+ *
+ * Cooling states are translated to frequencies throughout this driver and this
+ * is the relation between them.
+ *
+ * Highest cooling state corresponds to lowest possible frequency.
+ *
+ * i.e.
+ * level 0 --> 1st Max Freq
+ * level 1 --> 2nd Max Freq
+ * ...
+ */
+
/**
* struct cpufreq_cooling_device - data for cooling device with cpufreq
* @id: unique integer value corresponding to each cpufreq_cooling_device