Thermal core tries to read temperature during sensor registering in thermal_zone_of_sensor_register(). In that time Exynos TMU driver and hardware are not yet initialized. Commit 0eb875d88aaa ("thermal: exynos: Reading temperature makes sense only when TMU is turned on") added a boolean flag to prevent reading bogus temperature in such case but it exposed warning message during boot: [ 3.864913] thermal thermal_zone0: failed to read out thermal zone (-22) Return EAGAIN in such case to skip omitting such message because it might mislead user. Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> --- drivers/thermal/samsung/exynos_tmu.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c index 3b20309789e3..c24969d740d1 100644 --- a/drivers/thermal/samsung/exynos_tmu.c +++ b/drivers/thermal/samsung/exynos_tmu.c @@ -666,8 +666,14 @@ static int exynos_get_temp(void *p, int *temp) struct exynos_tmu_data *data = p; int value, ret = 0; - if (!data || !data->tmu_read || !data->enabled) + if (!data || !data->tmu_read) return -EINVAL; + else if (!data->enabled) + /* + * Called too early, probably + * from thermal_zone_of_sensor_register(). + */ + return -EAGAIN; mutex_lock(&data->lock); clk_enable(data->clk); -- 2.14.1 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html