From 098c5a6a14b7cb7727f370bcdcca693b3098e37f Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Wed, 25 Oct 2017 11:27:43 +0200 Subject: dt-bindings: iio: adc: stm32: add support for diff channels STM32H7 ADC channels may be configured either as single-ended or differential. Add 'st,adc-diff-channels' property to support differential channels. Differential channels are defined as a pair of positive and negative inputs: vinp & vinn. Signed-off-by: Fabrice Gasnier Acked-by: Rob Herring Signed-off-by: Jonathan Cameron --- .../devicetree/bindings/iio/adc/st,stm32-adc.txt | 24 ++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'Documentation/devicetree/bindings/iio/adc') diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt index 48bfcaa3ffcd..e8bb8243e92c 100644 --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt @@ -62,6 +62,15 @@ Required properties: - st,adc-channels: List of single-ended channels muxed for this ADC. It can have up to 16 channels on stm32f4 or 20 channels on stm32h7, numbered from 0 to 15 or 19 (resp. for in0..in15 or in0..in19). +- st,adc-diff-channels: List of differential channels muxed for this ADC. + Depending on part used, some channels can be configured as differential + instead of single-ended (e.g. stm32h7). List here positive and negative + inputs pairs as , ,... vinp and vinn are numbered + from 0 to 19 on stm32h7) + Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is required. + Both properties can be used together. Some channels can be used as + single-ended and some other ones as differential (mixed). But channels + can't be configured both as single-ended and differential (invalid). - #io-channel-cells = <1>: See the IIO bindings section "IIO consumers" in Documentation/devicetree/bindings/iio/iio-bindings.txt @@ -111,3 +120,18 @@ Example: ... other adc child nodes follow... }; + +Example to setup: +- channel 1 as single-ended +- channels 2 & 3 as differential (with resp. 6 & 7 negative inputs) + + adc: adc@40022000 { + compatible = "st,stm32h7-adc-core"; + ... + adc1: adc@0 { + compatible = "st,stm32h7-adc"; + ... + st,adc-channels = <1>; + st,adc-diff-channels = <2 6>, <3 7>; + }; + }; -- cgit v1.2.3-59-g8ed1b