From mboxrd@z Thu Jan 1 00:00:00 1970 From: Slawomir Stepien Subject: Re: [PATCH v3 1/8] iio:core: add a callback to allow drivers to provide _available attributes Date: Mon, 7 Nov 2016 17:46:41 +0100 Message-ID: <20161107164641.GA29162@x220.localdomain> References: <1477262381-7800-1-git-send-email-peda@axentia.se> <1477262381-7800-2-git-send-email-peda@axentia.se> <62f150ba-abc0-8e45-1355-8a61354ee3e1@axentia.se> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <62f150ba-abc0-8e45-1355-8a61354ee3e1@axentia.se> Sender: linux-kernel-owner@vger.kernel.org To: Peter Rosin Cc: Daniel Baluta , Linux Kernel Mailing List , Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Rob Herring , Mark Rutland , "linux-iio@vger.kernel.org" , Devicetree List List-Id: devicetree@vger.kernel.org On Nov 07, 2016 12:57, Peter Rosin wrote: > On 2016-11-07 12:37, Daniel Baluta wrote: > > On Mon, Oct 24, 2016 at 1:39 AM, Peter Rosin wrote: > >> From: Jonathan Cameron > >> > >> A large number of attributes can only take a limited range of values. > >> Currently in IIO this is handled by directly registering additional > >> *_available attributes thus providing this information to userspace. > >> > >> It is desirable to provide this information via the core for much the same > >> reason this was done for the actual channel information attributes in the > >> first place. If it isn't there, then it can only really be accessed from > >> userspace. Other in kernel IIO consumers have no access to what valid > >> parameters are. > >> > >> Two forms are currently supported: > >> * list of values in one particular IIO_VAL_* format. > >> e.g. 1.300000 1.500000 1.730000 > >> * range specification with a step size: > >> e.g. [1.000000 0.500000 2.500000] > >> equivalent to 1.000000 1.5000000 2.000000 2.500000 > > > > Is there any driver using this format? :) > > Yes, soon. Hopefully. See patch 3/8 > iio: mcp4531: provide range of available raw values > https://patchwork.kernel.org/patch/9391283/ I would also like to add this to mcp4131.c and ds1803.c. -- Slawomir Stepien