linux-kernel - [PATCH] thermal/of: support thermal zones w/o trips subnode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241028171901.2484882-1-daniel.lezcano@linaro.org>
Date: Mon, 28 Oct 2024 18:19:01 +0100
From: Daniel Lezcano <daniel.lezcano@...aro.org>
To: wenst@...omium.org,
	rafael@...nel.org
Cc: Icenowy Zheng <uwu@...nowy.me>,
	Zhang Rui <rui.zhang@...el.com>,
	Lukasz Luba <lukasz.luba@....com>,
	Matthias Brugger <matthias.bgg@...il.com>,
	AngeloGioacchino Del Regno <angelogioacchino.delregno@...labora.com>,
	linux-pm@...r.kernel.org (open list:THERMAL),
	linux-kernel@...r.kernel.org (open list),
	linux-arm-kernel@...ts.infradead.org (moderated list:ARM/Mediatek SoC support),
	linux-mediatek@...ts.infradead.org (moderated list:ARM/Mediatek SoC support)
Subject: [PATCH] thermal/of: support thermal zones w/o trips subnode

From: Icenowy Zheng <uwu@...nowy.me>

Although the current device tree binding of thermal zones require the
trips subnode, the binding in kernel v5.15 does not require it, and many
device trees shipped with the kernel, for example,
allwinner/sun50i-a64.dtsi and mediatek/mt8183-kukui.dtsi in ARM64, still
comply to the old binding and contain no trips subnode.

Allow the code to successfully register thermal zones w/o trips subnode
for DT binding compatibility now.

Furtherly, the inconsistency between DTs and bindings should be resolved
by either adding empty trips subnode or dropping the trips subnode
requirement.

Fixes: d0c75fa2c17f ("thermal/of: Initialize trip points separately")
Signed-off-by: Icenowy Zheng <uwu@...nowy.me>
[wenst@...omium.org: Reworked logic and kernel log messages]
Signed-off-by: Chen-Yu Tsai <wenst@...omium.org>
Reviewed-by: Rafael J. Wysocki <rafael@...nel.org>
Link: https://lore.kernel.org/r/20241018073139.1268995-1-wenst@chromium.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
---
 drivers/thermal/thermal_of.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
index a4caf7899f8e..07e09897165f 100644
--- a/drivers/thermal/thermal_of.c
+++ b/drivers/thermal/thermal_of.c
@@ -99,18 +99,15 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
 	struct device_node *trips;
 	int ret, count;
 
+	*ntrips = 0;
+	
 	trips = of_get_child_by_name(np, "trips");
-	if (!trips) {
-		pr_err("Failed to find 'trips' node\n");
-		return ERR_PTR(-EINVAL);
-	}
+	if (!trips)
+		return NULL;
 
 	count = of_get_child_count(trips);
-	if (!count) {
-		pr_err("No trip point defined\n");
-		ret = -EINVAL;
-		goto out_of_node_put;
-	}
+	if (!count)
+		return NULL;
 
 	tt = kzalloc(sizeof(*tt) * count, GFP_KERNEL);
 	if (!tt) {
@@ -133,7 +130,6 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
 
 out_kfree:
 	kfree(tt);
-	*ntrips = 0;
 out_of_node_put:
 	of_node_put(trips);
 
@@ -401,11 +397,14 @@ static struct thermal_zone_device *thermal_of_zone_register(struct device_node *
 
 	trips = thermal_of_trips_init(np, &ntrips);
 	if (IS_ERR(trips)) {
-		pr_err("Failed to find trip points for %pOFn id=%d\n", sensor, id);
+		pr_err("Failed to parse trip points for %pOFn id=%d\n", sensor, id);
 		ret = PTR_ERR(trips);
 		goto out_of_node_put;
 	}
 
+	if (!trips)
+		pr_info("No trip points found for %pOFn id=%d\n", sensor, id);
+
 	ret = thermal_of_monitor_init(np, &delay, &pdelay);
 	if (ret) {
 		pr_err("Failed to initialize monitoring delays from %pOFn\n", np);
-- 
2.43.0