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. We currently have a driver for the two latter functions in drivers/input/touchscreen/sun4i-ts.c but we don't have access to the ADC feature at all. It is meant to replace the current driver by using MFD and subdrivers. The Allwinner A33 only has a thermal sensor present in the GPADC. In addition, there is not an existing DT binding for the GPADC. Thus, we do not need the sun4i-gpadc MFD driver which was made to keep DT compatibility and probe subdrivers without the need to add DT subnodes. This series of patch adds the CPU thermal sensor for the A33 and CPU thermal throttling. It also adds DT binding documentation for the IIO and MFD GPADC drivers. Finally, it adds the cpu-supply property to the CPU node needed by the Sinlinx SinA33 and Olinuxino A33 to adapt their CPU regulator voltage depending on the currently used OPP. The other A33 boards all have their cpu-supply property set. This patch *HAS NOT* been tested on the Olinuxino A33. @Stefan (or anyone owning an Olinuxino A33), could you test this patch series on your board, test CPUfreq and tell us if it works in a stable manner? Thanks! This series of patch is based on this[1] and this[2][3] series of patch. [1] https://lkml.org/lkml/2016/12/13/298 : "[PATCH v9] add support for Allwinner SoCs ADC" [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-December/473962.html : "[PATCH] Allwinner A33 CPU frequency scaling support" without PATCH 4/6 [3] https://lkml.org/lkml/2016/12/19/72 : "[PATCH v2] ARM: dts: sun8i: add opp-v2 table for A33" Quentin Schulz (7): Documentation: DT: bindings: iio: adc: add documentation for Allwinner SoCs' GPADC driver Documentation: DT: bindings: mfd: add documentation for Allwinner SoCs' GPADC MFD driver iio: adc: sun4i-gpadc-iio: add support for A33 thermal sensor ARM: dts: sun8i-a33-sinlinx-sina33: add cpu-supply ARM: dts: sun8i-a33-olinuxino: add cpu-supply ARM: dtsi: sun8i-a33: add A33 thermal sensor ARM: dtsi: sun8i-a33: add CPU thermal throttling .../bindings/iio/adc/sun4i-gpadc-iio.txt | 57 ++++++ .../devicetree/bindings/mfd/sun4i-gpadc.txt | 47 +++++ arch/arm/boot/dts/sun8i-a33-olinuxino.dts | 4 + arch/arm/boot/dts/sun8i-a33-sinlinx-sina33.dts | 4 + arch/arm/boot/dts/sun8i-a33.dtsi | 59 ++++++ drivers/iio/adc/Kconfig | 21 ++- drivers/iio/adc/sun4i-gpadc-iio.c | 204 ++++++++++++++++----- include/linux/mfd/sun4i-gpadc.h | 4 + 8 files changed, 343 insertions(+), 57 deletions(-) create mode 100644 Documentation/devicetree/bindings/iio/adc/sun4i-gpadc-iio.txt create mode 100644 Documentation/devicetree/bindings/mfd/sun4i-gpadc.txt -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
