[PATCH 1/4] thermal/drivers/qcom: fix set_trip_temp() deadlock

From: Johan Hovold
Date: Wed Dec 14 2022 - 08:19:22 EST


The set_trip_temp() callback is used when changing the trip temperature
through sysfs. As it is called with the thermal-zone-device lock held
it must not use thermal_zone_get_trip() directly or it will deadlock.

Fixes: 78c3e2429be8 ("thermal/drivers/qcom: Use generic thermal_zone_get_trip() function")
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
---
drivers/thermal/qcom/qcom-spmi-temp-alarm.c | 2 +-
drivers/thermal/thermal_core.c | 1 +
include/linux/thermal.h | 2 ++
3 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
index 58055a7abaf6..bfaec74f13b2 100644
--- a/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
+++ b/drivers/thermal/qcom/qcom-spmi-temp-alarm.c
@@ -270,7 +270,7 @@ static int qpnp_tm_set_trip_temp(struct thermal_zone_device *tz, int trip_id, in
struct thermal_trip trip;
int ret;

- ret = thermal_zone_get_trip(chip->tz_dev, trip_id, &trip);
+ ret = __thermal_zone_get_trip(chip->tz_dev, trip_id, &trip);
if (ret)
return ret;

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index c24c9efcd175..d9a3d9566d73 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -1214,6 +1214,7 @@ int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,

return tz->ops->get_trip_type(tz, trip_id, &trip->type);
}
+EXPORT_SYMBOL_GPL(__thermal_zone_get_trip);

int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip)
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index e2797f314d99..30353e4b1424 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -334,6 +334,8 @@ static inline void devm_thermal_of_zone_unregister(struct device *dev,
}
#endif

+int __thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
+ struct thermal_trip *trip);
int thermal_zone_get_trip(struct thermal_zone_device *tz, int trip_id,
struct thermal_trip *trip);

--
2.37.4