From 80d87477bed1199b620bf8bb297a1f060ec98195 Mon Sep 17 00:00:00 2001
From: Konrad Dybcio <konrad.dybcio@linaro.org>
Date: Sat, 9 Mar 2024 14:15:03 +0100
Subject: [PATCH] thermal/drivers/qcom/lmh: Check for SCM availability at probe

BugLink: https://bugs.launchpad.net/bugs/2073788

commit d9d3490c48df572edefc0b64655259eefdcbb9be upstream.

Up until now, the necessary scm availability check has not been
performed, leading to possible null pointer dereferences (which did
happen for me on RB1).

Fix that.

Fixes: 53bca371cdf7 ("thermal/drivers/qcom: Add support for LMh driver")
Cc: <stable@vger.kernel.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20240308-topic-rb1_lmh-v2-2-bac3914b0fe3@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
---
 drivers/thermal/qcom/lmh.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/thermal/qcom/lmh.c b/drivers/thermal/qcom/lmh.c
index f6edb12ec004..5225b3621a56 100644
--- a/drivers/thermal/qcom/lmh.c
+++ b/drivers/thermal/qcom/lmh.c
@@ -95,6 +95,9 @@ static int lmh_probe(struct platform_device *pdev)
 	unsigned int enable_alg;
 	u32 node_id;
 
+	if (!qcom_scm_is_available())
+		return -EPROBE_DEFER;
+
 	lmh_data = devm_kzalloc(dev, sizeof(*lmh_data), GFP_KERNEL);
 	if (!lmh_data)
 		return -ENOMEM;