[PATCH 17/17] thermal: warn on attempts to read temperature on disabled sensors

From: Bartlomiej Zolnierkiewicz
Date: Tue Apr 10 2018 - 08:45:10 EST


* Add ops_of_thermal flag to struct thermal_zone_device_ops and
set it in of-thermal.c.

* Add checking sensor mode for drivers using of-thermal.c to
thermal_zone_get_temp() (print a warning if sensor is disabled).

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
---
drivers/thermal/of-thermal.c | 2 ++
drivers/thermal/thermal_helpers.c | 12 ++++++++++++
include/linux/thermal.h | 1 +
3 files changed, 15 insertions(+)

diff --git a/drivers/thermal/of-thermal.c b/drivers/thermal/of-thermal.c
index f60ccf1..68ebcda 100644
--- a/drivers/thermal/of-thermal.c
+++ b/drivers/thermal/of-thermal.c
@@ -392,6 +392,8 @@ static int of_thermal_get_crit_temp(struct thermal_zone_device *tz,

.bind = of_thermal_bind,
.unbind = of_thermal_unbind,
+
+ .ops_of_thermal = true,
};

/*** sensor API ***/
diff --git a/drivers/thermal/thermal_helpers.c b/drivers/thermal/thermal_helpers.c
index bd10b4d..e3fc1c6 100644
--- a/drivers/thermal/thermal_helpers.c
+++ b/drivers/thermal/thermal_helpers.c
@@ -87,6 +87,18 @@ int thermal_zone_get_temp(struct thermal_zone_device *tz, int *temp)
if (!tz || IS_ERR(tz) || !tz->ops->get_temp)
goto exit;

+ if (tz->ops->ops_of_thermal) {
+ enum thermal_device_mode mode;
+
+ ret = tz->ops->get_mode(tz, &mode);
+ if (ret)
+ goto exit;
+
+ if (mode == THERMAL_DEVICE_DISABLED)
+ dev_warn_once(&tz->device,
+ "trying to read out disabled thermal zone\n");
+ }
+
mutex_lock(&tz->lock);

ret = tz->ops->get_temp(tz, temp);
diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index 7de102f..31560b4 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h
@@ -130,6 +130,7 @@ struct thermal_zone_device_ops {
enum thermal_trip_type);

bool set_mode_skip_check;
+ bool ops_of_thermal;
};

struct thermal_cooling_device_ops {
--
1.9.1