From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Blumenstingl Subject: Re: [PATCH 1/3] Documentation: dt-bindings: add the Amlogic Meson Temperature Sensor Date: Thu, 6 Jun 2019 21:16:37 +0200 Message-ID: References: <20190604144714.2009-1-glaroque@baylibre.com> <20190604144714.2009-2-glaroque@baylibre.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20190604144714.2009-2-glaroque@baylibre.com> Sender: linux-kernel-owner@vger.kernel.org To: Guillaume La Roque Cc: jic23@kernel.org, khilman@baylibre.com, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-amlogic@lists.infradead.org List-Id: devicetree@vger.kernel.org Hi Guillaume, thank you for working on this! On Tue, Jun 4, 2019 at 4:47 PM Guillaume La Roque wrote: > > This adds the devicetree binding documentation for the Temperature > Sensor found in the Amlogic Meson G12 SoCs. > Currently only the G12A SoCs are supported. so G12B is not supported (yet)? > Signed-off-by: Guillaume La Roque > --- > .../iio/temperature/amlogic,meson-tsensor.txt | 31 +++++++++++++++++++ > 1 file changed, 31 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/temperature/amlogic,meson-tsensor.txt > > diff --git a/Documentation/devicetree/bindings/iio/temperature/amlogic,meson-tsensor.txt b/Documentation/devicetree/bindings/iio/temperature/amlogic,meson-tsensor.txt > new file mode 100644 > index 000000000000..d064db0e9cac > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/temperature/amlogic,meson-tsensor.txt > @@ -0,0 +1,31 @@ > +* Amlogic Meson Temperature Sensor > + > +Required properties: > +- compatible: depending on the SoC and the position of the sensor, > + this should be one of: > + - "amlogic,meson-g12a-cpu-tsensor" for the CPU G12A SoC sensor > + - "amlogic,meson-g12a-ddr-tsensor" for the DDR G12A SoC sensor > + followed by the common : > + - "amlogic,meson-g12a-tsensor" for G12A SoC family > +- reg: the physical base address and length of the registers > +- interrupts: the interrupt indicating end of sampling > +- clocks: phandle identifier for the reference clock of temperature sensor > +- #io-channel-cells: must be 1, see ../iio-bindings.txt have you considered using the thermal framework [0] instead of the iio framework (see below)? > +- amlogic,ao-secure: phandle to the ao-secure syscon the driver has some "u_efuse_off" access. do we need to get some calibration values from the AO syscon or can we also fetch it from the eFuse? you can look at arch/arm/boot/dts/meson8.dtsi where I'm passing the temperature sensor calibration data to the SAR ADC (there's no dedicated temperature sensor IP block prior to G12A) while reading the data from the eFuse > +Optional properties: > +- amlogic,critical-temperature: temperature value in milli degrees Celsius > + to set automatic reboot on too high temperature as far as I can tell the thermal framework supports multiple trip points. I'm seeing this as a benefit because the hardware can raise interrupts at four different temperatures (defined by the driver) > +Example: > + cpu_temp: temperature-sensor@ff634800 { > + compatible = "amlogic,meson-g12a-cpu-tsensor", > + "amlogic,meson-g12a-tsensor"; > + reg = <0x0 0xff634800 0x0 0x50>; > + interrupts = ; > + clocks = <&clkc CLKID_TS>; > + status = "okay"; as far as I know the dt-bindings should not have a status property in the examples Martin