thermal: thermal_core: allow binding with limits on bind_params

When registering a thermal zone device using platform information
via bind_params, the thermal framework will always perform the
cdev binding using the lowest and highest limits (THERMAL_NO_LIMIT).

This patch changes the data structures so that it is possible
to inform what are the desired limits for each trip point
inside a bind_param. The way the binding is performed is also
changed so that it uses the new data structure.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>

Documentation/thermal/sysfs-api.txt

@@ -134,6 +134,13 @@ temperature) and throttle appropriate devices.
                this thermal zone and cdev, for a particular trip point.
                If nth bit is set, then the cdev and thermal zone are bound
                for trip point n.
+    .limits: This is an array of cooling state limits. Must have exactly
+         2 * thermal_zone.number_of_trip_points. It is an array consisting
+         of tuples <lower-state upper-state> of state limits. Each trip
+         will be associated with one state limit tuple when binding.
+         A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
+         on all trips. These limits are used when binding a cdev to a
+         trip point.
     .match: This call back returns success(0) if the 'tz and cdev' need to
 	    be bound, as per platform data.
 1.4.2 struct thermal_zone_params

drivers/thermal/thermal_core.c

@@ -202,14 +202,23 @@ static void print_bind_err_msg(struct thermal_zone_device *tz,
 }
 
 static void __bind(struct thermal_zone_device *tz, int mask,
-			struct thermal_cooling_device *cdev)
+			struct thermal_cooling_device *cdev,
+			unsigned long *limits)
 {
 	int i, ret;
 
 	for (i = 0; i < tz->trips; i++) {
 		if (mask & (1 << i)) {
+			unsigned long upper, lower;
+
+			upper = THERMAL_NO_LIMIT;
+			lower = THERMAL_NO_LIMIT;
+			if (limits) {
+				lower = limits[i * 2];
+				upper = limits[i * 2 + 1];
+			}
 			ret = thermal_zone_bind_cooling_device(tz, i, cdev,
-					THERMAL_NO_LIMIT, THERMAL_NO_LIMIT);
+							       upper, lower);
 			if (ret)
 				print_bind_err_msg(tz, cdev, ret);
 		}
@@ -254,7 +263,8 @@ static void bind_cdev(struct thermal_cooling_device *cdev)
 			if (tzp->tbp[i].match(pos, cdev))
 				continue;
 			tzp->tbp[i].cdev = cdev;
-			__bind(pos, tzp->tbp[i].trip_mask, cdev);
+			__bind(pos, tzp->tbp[i].trip_mask, cdev,
+			       tzp->tbp[i].binding_limits);
 		}
 	}
 
@@ -292,7 +302,8 @@ static void bind_tz(struct thermal_zone_device *tz)
 			if (tzp->tbp[i].match(tz, pos))
 				continue;
 			tzp->tbp[i].cdev = pos;
-			__bind(tz, tzp->tbp[i].trip_mask, pos);
+			__bind(tz, tzp->tbp[i].trip_mask, pos,
+			       tzp->tbp[i].binding_limits);
 		}
 	}
 exit:

include/linux/thermal.h

@@ -207,6 +207,16 @@ struct thermal_bind_params {
 	 * See Documentation/thermal/sysfs-api.txt for more information.
 	 */
 	int trip_mask;
+
+	/*
+	 * This is an array of cooling state limits. Must have exactly
+	 * 2 * thermal_zone.number_of_trip_points. It is an array consisting
+	 * of tuples <lower-state upper-state> of state limits. Each trip
+	 * will be associated with one state limit tuple when binding.
+	 * A NULL pointer means <THERMAL_NO_LIMITS THERMAL_NO_LIMITS>
+	 * on all trips.
+	 */
+	unsigned long *binding_limits;
 	int (*match) (struct thermal_zone_device *tz,
 			struct thermal_cooling_device *cdev);
 };