Subject: Re: [PATCH 1/4] dt-bindings: iio: stm32-dac: Add support for STM32
 DAC
To: Rob Herring <robh@kernel.org>
References: <1490960707-22422-1-git-send-email-fabrice.gasnier@st.com>
 <1490960707-22422-2-git-send-email-fabrice.gasnier@st.com>
 <20170403164240.hw4wza7y3s5faivb@rob-hp-laptop>
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        <linux-kernel@vger.kernel.org>, <linux-iio@vger.kernel.org>,
        <mark.rutland@arm.com>, <mcoquelin.stm32@gmail.com>,
        <alexandre.torgue@st.com>, <lars@metafoo.de>, <knaack.h@gmx.de>,
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        <amelie.delaunay@st.com>
From: Fabrice Gasnier <fabrice.gasnier@st.com>
Message-ID: <94c63ce8-c48e-edbc-8e71-95b4aefd55cf@st.com>
Date: Wed, 5 Apr 2017 16:48:20 +0200
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On 04/03/2017 06:42 PM, Rob Herring wrote:
> On Fri, Mar 31, 2017 at 01:45:04PM +0200, Fabrice Gasnier wrote:
>> Document STMicroelectronics STM32 DAC (digital-to-analog converter).
>>
>> Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
>> ---
>>  .../devicetree/bindings/iio/dac/st,stm32-dac.txt   | 56 ++++++++++++++++++++++
>>  1 file changed, 56 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/iio/dac/st,stm32-dac.txt
>>
>> diff --git a/Documentation/devicetree/bindings/iio/dac/st,stm32-dac.txt b/Documentation/devicetree/bindings/iio/dac/st,stm32-dac.txt
>> new file mode 100644
>> index 0000000..1981983
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/dac/st,stm32-dac.txt
>> @@ -0,0 +1,56 @@
>> +STMicroelectronics STM32 DAC
>> +
>> +The STM32 DAC is a 12-bit voltage output digital-to-analog converter. The DAC
>> +can be configured in 8- or 12-bit mode. In 12-bit mode, the data could be
>> +left- or right-aligned. It has two output channels, each with its own converter.
>> +It has built-in noise and triangle waveform generator and supports external
>> +triggers for conversions. The DAC's output buffer allows a high drive output
>> +current.
>> +
>> +Contents of a stm32 dac root node:
>> +-----------------------------------
>> +Required properties:
>> +- compatible: Must be "st,stm32h7-dac-core".
>> +- reg: Offset and length of the device's register set.
>> +- clocks: Must contain an entry for pclk (which feeds the peripheral bus
>> +  interface)
>> +- clock-names: Must be "pclk".
>> +- vref-supply: Phandle to the vref+ input analog reference supply.
>> +
>> +Optional properties:
>> +- resets: Must contain the phandle to the reset controller.
>> +- A pinctrl state named "default" for each DAC channel may be defined to set
>> +  DAC_OUTx pin in mode of operation for analog output on external pin.
>> +
>> +Contents of a stm32 dac child node:
>> +-----------------------------------
>> +DAC core node should contain at least one subnode, representing a
>> +DAC instance/channel available on the machine.
>> +
>> +Required properties:
>> +- compatible: Must be "st,stm32-dac".
>> +- #io-channel-cells = <1>: See the IIO bindings section "IIO consumers" in
>> +  Documentation/devicetree/bindings/iio/iio-bindings.txt
>> +- st,dac-channel: Must be either 1 or 2, to define channel in use (e.g.
>> +  single channels: 1 or 2)
> 
> Use "reg" instead.

Hi Rob,

Thanks your reviewing. I'll update this in V2

Best Regards,
Fabrice

> 
>> +
>> +Example:
>> +	dac: dac@40007400 {
>> +		compatible = "st,stm32h7-dac-core";
>> +		reg = <0x40007400 0x400>;
>> +		clocks = <&clk>;
>> +		clock-names = "pclk";
>> +		vref-supply = <&reg_vref>;
>> +
>> +		dac1: dac@1 {
>> +			compatible = "st,stm32-dac";
>> +			#io-channels-cells = <1>;
>> +			st,dac-channel = <1>;
>> +		};
>> +
>> +		dac2: dac@2 {
>> +			compatible = "st,stm32-dac";
>> +			#io-channels-cells = <1>;
>> +			st,dac-channel = <2>;
>> +		};
>> +	};
>> -- 
>> 1.9.1
>>