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Test for them and return -ENODATA to hwmon. Signed-off-by: Eugene Shalygin --- drivers/hwmon/asus-ec-sensors.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/asus-ec-sensors.c b/drivers/hwmon/asus-ec-sensors.c index 29a23484cbe7..f178570110c1 100644 --- a/drivers/hwmon/asus-ec-sensors.c +++ b/drivers/hwmon/asus-ec-sensors.c @@ -67,6 +67,13 @@ static char *mutex_path_override; /* Moniker for the ACPI global lock (':' is not allowed in ASL identifiers) */ #define ACPI_GLOBAL_LOCK_PSEUDO_PATH ":GLOBAL_LOCK" +/* + * The values for temperature sensor readings without physical sensors connected. + * The value varies across generations and is seemingly defined by the EC chip + * used in the given board. + */ +static s32 temperature_blank_values[] = {-62, -60, -40}; + typedef union { u32 value; struct { @@ -1291,6 +1298,17 @@ static int get_cached_value_or_update(const struct device *dev, return 0; } +static bool is_blank_temperature_value(s32 value) +{ + size_t i; + + for (i = 0; i < ARRAY_SIZE(temperature_blank_values); ++i) { + if (value == temperature_blank_values[i]) + return true; + } + return false; +} + /* * Now follow the functions that implement the hwmon interface */ @@ -1298,6 +1316,7 @@ static int get_cached_value_or_update(const struct device *dev, static int asus_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { + const struct ec_sensor_info *sensor_info; int ret; s32 value = 0; @@ -1310,8 +1329,12 @@ static int asus_ec_hwmon_read(struct device *dev, enum hwmon_sensor_types type, ret = get_cached_value_or_update(dev, sidx, state, &value); if (!ret) { - *val = scale_sensor_value(value, - get_sensor_info(state, sidx)->type); + sensor_info = get_sensor_info(state, sidx); + if (sensor_info->type == hwmon_temp && + is_blank_temperature_value(value)) { + return -ENODATA; + } + *val = scale_sensor_value(value, sensor_info->type); } return ret; -- 2.55.0