Message ID | 20161213143332.24988-2-quentin.schulz@free-electrons.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On Tue, Dec 13, 2016 at 03:33:30PM +0100, Quentin Schulz wrote: > This enables CONFIG_THERMAL_OF by default for sunxi_defconfig. It is > required to get Allwinner SoCs' temperature from the GPADC driver. > > The Allwinner SoCs all have an ADC that can also act as a touchscreen > controller and a thermal sensor. The first four channels can be used > either for the ADC or the touchscreen and the fifth channel is used for > the thermal sensor. > > The thermal sensor requires the IP to be in touchscreen mode to return > correct values. Therefore, if the user is continuously reading the ADC > channel(s), the thermal framework in which the thermal sensor is > registered will switch the IP in touchscreen mode to get a temperature > value and requires a delay of 100ms (because of the mode switching), > then the ADC will switch back to ADC mode and requires also a delay of > 100ms. If the ADC readings are critical to user and the SoC temperature > is not, the GPADC driver is capable of not registering the thermal > sensor in the thermal framework and thus, "quicken" the ADC readings. In > most use cases, the SoC temperature is more critical (for cpu throttling > for example or activating cooling devices) than ADC readings, thus it is > now enabled by default. > > Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> Applied, thanks! Maxime
diff --git a/arch/arm/configs/sunxi_defconfig b/arch/arm/configs/sunxi_defconfig index 714da33..8aaeae3 100644 --- a/arch/arm/configs/sunxi_defconfig +++ b/arch/arm/configs/sunxi_defconfig @@ -83,6 +83,7 @@ CONFIG_GPIO_SYSFS=y CONFIG_POWER_SUPPLY=y CONFIG_AXP20X_POWER=y CONFIG_THERMAL=y +CONFIG_THERMAL_OF=y CONFIG_CPU_THERMAL=y CONFIG_WATCHDOG=y CONFIG_SUNXI_WATCHDOG=y
This enables CONFIG_THERMAL_OF by default for sunxi_defconfig. It is required to get Allwinner SoCs' temperature from the GPADC driver. The Allwinner SoCs all have an ADC that can also act as a touchscreen controller and a thermal sensor. The first four channels can be used either for the ADC or the touchscreen and the fifth channel is used for the thermal sensor. The thermal sensor requires the IP to be in touchscreen mode to return correct values. Therefore, if the user is continuously reading the ADC channel(s), the thermal framework in which the thermal sensor is registered will switch the IP in touchscreen mode to get a temperature value and requires a delay of 100ms (because of the mode switching), then the ADC will switch back to ADC mode and requires also a delay of 100ms. If the ADC readings are critical to user and the SoC temperature is not, the GPADC driver is capable of not registering the thermal sensor in the thermal framework and thus, "quicken" the ADC readings. In most use cases, the SoC temperature is more critical (for cpu throttling for example or activating cooling devices) than ADC readings, thus it is now enabled by default. Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> --- v8: - more explanatory commit log, added in v7 arch/arm/configs/sunxi_defconfig | 1 + 1 file changed, 1 insertion(+)