• Quentin Schulz's avatar
    ARM: sunxi: Add CONFIG_THERMAL_OF · 11937f69
    Quentin Schulz authored
    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: default avatarQuentin Schulz <quentin.schulz@free-electrons.com>
    Signed-off-by: default avatarMaxime Ripard <maxime.ripard@free-electrons.com>
sunxi_defconfig 3.57 KB