From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751629AbdBYPPd (ORCPT ); Sat, 25 Feb 2017 10:15:33 -0500 Received: from saturn.retrosnub.co.uk ([178.18.118.26]:46085 "EHLO saturn.retrosnub.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751407AbdBYPPc (ORCPT ); Sat, 25 Feb 2017 10:15:32 -0500 Subject: Re: [PATCH 1/2] dt-bindings: iio: stm32-adc: add option to set resolution To: Fabrice Gasnier , linux@armlinux.org.uk, robh+dt@kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <1487177757-19427-1-git-send-email-fabrice.gasnier@st.com> <1487177757-19427-2-git-send-email-fabrice.gasnier@st.com> Cc: linux-iio@vger.kernel.org, mark.rutland@arm.com, mcoquelin.stm32@gmail.com, alexandre.torgue@st.com, lars@metafoo.de, knaack.h@gmx.de, pmeerw@pmeerw.net From: Jonathan Cameron Message-ID: Date: Sat, 25 Feb 2017 15:11:59 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 24/02/17 16:04, Fabrice Gasnier wrote: > On 02/19/2017 01:09 PM, Jonathan Cameron wrote: >> On 15/02/17 16:55, Fabrice Gasnier wrote: >>> Add documentation for 'st,adc-res' dt optional property. >>> >>> Signed-off-by: Fabrice Gasnier >> I'm happy with this, but would like to leave time for a device tree review. >> >> Ultimately we may well want to make this a generic property and call it something >> like adc-resolution but perhaps we need to wait until we have a few more devices >> supporting setting it via device tree to figure out what the best interface is. >> It would exactly be a problem to support this as a deprecated binding at that >> point. > > Hi Jonathan, > > I agree with you on this... It may be better to have generic property > for this, especially if you see that it will come in the near future. > May I suggest this prop to be less restrictive, e.g. like > resolution-bits as is may also be worth for other device types, e.g. > DAC as an example ?> Sure, why not - no loss of meaning here. We may never use it for anything else but that doesn't matter. >> >> Give me a poke if we hear nothing from Rob or Mark for say another week. > > No news yet, but it can wait a little longer. Rob / Mark, can you take a look at this if you have time? Thanks, Jonathan > > Please advise, > Regards, > Fabrice > >> >> Thanks, >> >> Jonathan >> >>> --- >>> Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt | 4 ++++ >>> 1 file changed, 4 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt >>> index 5dfc88e..45f7ff2 100644 >>> --- a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt >>> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt >>> @@ -57,6 +57,9 @@ Optional properties: >>> - dmas: Phandle to dma channel for this ADC instance. >>> See ../../dma/dma.txt for details. >>> - dma-names: Must be "rx" when dmas property is being used. >>> +- st,adc-res: Resolution (bits) to use for conversions. Must match device >>> + available resolutions (e.g. can be 6, 8, 10 or 12 on stm32f4). Default >>> + is maximum resolution if unset. >>> >>> Example: >>> adc: adc@40012000 { >>> @@ -84,6 +87,7 @@ Example: >>> st,adc-channels = <8>; >>> dmas = <&dma2 0 0 0x400 0x0>; >>> dma-names = "rx"; >>> + st,adc-res = <8>; >>> }; >>> ... >>> other adc child nodes follow... >>> >> > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html