Hi Krzysztof,
On 12 February 2017 at 01:44, Krzysztof Kozlowski <k...@kernel.org> wrote: > In Odroid XU3 Lite board, the temperature levels reported for thermal > zone 0 were weird. In warm room: > /sys/class/thermal/thermal_zone0/temp:32000 > /sys/class/thermal/thermal_zone1/temp:51000 > /sys/class/thermal/thermal_zone2/temp:55000 > /sys/class/thermal/thermal_zone3/temp:54000 > /sys/class/thermal/thermal_zone4/temp:51000 > > Sometimes after booting the value was even equal to ambient temperature > which is highly unlikely to be a real temperature of sensor in SoC. > > The thermal sensor's calibration (trimming) is based on fused values. > In case of the board above, the fused values are: 35, 52, 43, 58 and 43 > (corresponding to each TMU device). However driver defined a minimum value > for fused data as 40 and for smaller values it was using a hard-coded 55 > instead. This lead to mapping data from sensor to wrong temperatures > for thermal zone 0. > > Various vendor 3.10 trees (Hardkernel's based on Samsung LSI, Artik 10) > do not impose any limits on fused values. Since we do not have any > knowledge about these limits, use 0 as a minimum accepted fused value. > This should essentially allow accepting any reasonable fused value thus > behaving like vendor driver. > On HK following values are define in drivers/thermal/exynos_thermal.c #define EFUSE_MIN_VALUE 40 #define EFUSE_MAX_VALUE 100 > The exynos5420-tmu-sensor-conf.dtsi is copied directly from existing > exynso4412 with one change - the samsung,tmu_min_efuse_value. > > Signed-off-by: Krzysztof Kozlowski <k...@kernel.org> > > --- Best Regards -Anand
