staging: ti-soc-thermal: Introduce HAS_HISTORY_BUFFER feature for bandgap

The patch introduces HISTORY_BUFFER feature. This is present in OMAP5 bandgap
and it is a hardware history buffer of previously read temperatures.

Signed-off-by: J Keerthy <j-keerthy@ti.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ti-soc-thermal/ti-bandgap.h

@@ -315,6 +315,9 @@ struct ti_temp_sensor {
  * TI_BANDGAP_FEATURE_COUNTER_DELAY - used when the bandgap device features
  *	a delay programming based on distinct values.
  *
+ * TI_BANDGAP_FEATURE_HISTORY_BUFFER - used when the bandgap device features
+ *	a history buffer of temperatures.
+ *
  * TI_BANDGAP_HAS(b, f) - macro to check if a bandgap device is capable of a
  *      specific feature (above) or not. Return non-zero, if yes.
  */
@@ -327,6 +330,7 @@ struct ti_temp_sensor {
 #define TI_BANDGAP_FEATURE_CLK_CTRL		BIT(6)
 #define TI_BANDGAP_FEATURE_FREEZE_BIT		BIT(7)
 #define TI_BANDGAP_FEATURE_COUNTER_DELAY	BIT(8)
+#define TI_BANDGAP_FEATURE_HISTORY_BUFFER	BIT(9)
 #define TI_BANDGAP_HAS(b, f)			\
 			((b)->conf->features & TI_BANDGAP_FEATURE_ ## f)