intel_menlow: Add comment documenting legal GTHS values

Signed-off-by: Sujith Thomas <sujith.thomas@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/misc/intel_menlow.c b/drivers/misc/intel_menlow.c
index 124b37d..27b7662 100644
--- a/drivers/misc/intel_menlow.c
+++ b/drivers/misc/intel_menlow.c
@@ -52,6 +52,11 @@
 #define MEMORY_ARG_CUR_BANDWIDTH 1
 #define MEMORY_ARG_MAX_BANDWIDTH 0
 
+/*
+ * GTHS returning 'n' would mean that [0,n-1] states are supported
+ * In that case max_cstate would be n-1
+ * GTHS returning '0' would mean that no bandwidth control states are supported
+ */
 static int memory_get_int_max_bandwidth(struct thermal_cooling_device *cdev,
 					unsigned long *max_state)
 {