linux-kernel - [PATCH v1 5/6] thermal: gov_bang_bang: Drop unnecessary cooling device target state checks

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Date: Fri, 10 May 2024 16:19:32 +0200
From: "Rafael J. Wysocki" <rjw@...ysocki.net>
To: Linux PM <linux-pm@...r.kernel.org>
Cc: LKML <linux-kernel@...r.kernel.org>,
 "Rafael J. Wysocki" <rafael@...nel.org>, Lukasz Luba <lukasz.luba@....com>,
 Daniel Lezcano <daniel.lezcano@...aro.org>,
 Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>,
 Zhang Rui <rui.zhang@...el.com>
Subject:
 [PATCH v1 5/6] thermal: gov_bang_bang: Drop unnecessary cooling device target
 state checks

From: Rafael J. Wysocki <rafael.j.wysocki@...el.com>

Some cooling device target state checks in bang_bang_control()
done before setting the new target state are not necessary after
recent changes, so drop them.

Also avoid updating the target state before checking it for
unexpected values.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@...el.com>
---
 drivers/thermal/gov_bang_bang.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

Index: linux-pm/drivers/thermal/gov_bang_bang.c
===================================================================
--- linux-pm.orig/drivers/thermal/gov_bang_bang.c
+++ linux-pm/drivers/thermal/gov_bang_bang.c
@@ -57,24 +57,16 @@ static void bang_bang_control(struct the
 		if (instance->trip != trip)
 			continue;

-		if (instance->target == THERMAL_NO_TARGET)
-			instance->target = 0;
-
-		if (instance->target != 0 && instance->target != 1) {
+		if (instance->target != 0 && instance->target != 1 &&
+		    instance->target != THERMAL_NO_TARGET)
 			pr_debug("Unexpected state %ld of thermal instance %s in bang-bang\n",
 				 instance->target, instance->name);

-			instance->target = 1;
-		}
-
 		/*
 		 * Enable the fan when the trip is crossed on the way up and
 		 * disable it when the trip is crossed on the way down.
 		 */
-		if (instance->target == 0 && crossed_up)
-			instance->target = 1;
-		else if (instance->target == 1 && !crossed_up)
-			instance->target = 0;
+		instance->target = crossed_up;

 		dev_dbg(&instance->cdev->device, "target=%ld\n", instance->target);