From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ppsw-41.csi.cam.ac.uk ([131.111.8.141]:60540 "EHLO ppsw-41.csi.cam.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751773Ab0K3Q4K (ORCPT ); Tue, 30 Nov 2010 11:56:10 -0500 Message-ID: <4CF52E43.2000105@cam.ac.uk> Date: Tue, 30 Nov 2010 17:02:59 +0000 From: Jonathan Cameron MIME-Version: 1.0 To: "Hennerich, Michael" CC: "linux-iio@vger.kernel.org" , Drivers , "device-drivers-devel@blackfin.uclinux.org" Subject: Re: [PATCH] staging: iio: dds: ad9834: Enable driver support for AD9833 and AD9834 DDS devices References: <1291045919-11141-1-git-send-email-michael.hennerich@analog.com> <4CF43350.4000703@cam.ac.uk> <544AC56F16B56944AEC3BD4E3D591771312F081809@LIMKCMBX1.ad.analog.com> <4CF52280.2050600@cam.ac.uk> <544AC56F16B56944AEC3BD4E3D591771312F0818BD@LIMKCMBX1.ad.analog.com> In-Reply-To: <544AC56F16B56944AEC3BD4E3D591771312F0818BD@LIMKCMBX1.ad.analog.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 11/30/10 16:44, Hennerich, Michael wrote: >> Jonathan Cameron wrote on 2010-11-30: >>>> From a generalization point of view we don't care that the square wave >>>> is a random bonus option the part happens to be able to kick out. >>>> Ideally we want a naming scheme that makes it's relationship to the >>>> other waveforms apparent though and it's not entirely obvious how to >>>> handle that (e.g. how to handle the double frequency square wave this >>>> part can produce). Things will get more fun if parts have multiple >>>> outputs tied to one dds channel. >>> >>> Actually that's the case here on the AD9834. The signbit is an >>> independent output. It therefore can't be handled with the >> dds0_wavetype file. >> Then have dds0_wavetype0 (sine triangle) and dds0_wavetype1 (square). >> Document that the second index is only required if there are multiple >> physical outputs from a given channel. > > How to disable dds0_wavetype1 (square)? > > (square off)? Nope, it's just like the other output in that it can be disabled so give it it's own disable attribute. The naming currently proposed looks a little strange for this... hmm. Perhaps change to dds0_out1_wavetype etc for the other elements. dds0_out_disable (for both) and dds0_out1_disable allows this channel to be separately disabled. > > Not all combinations of dds0_wavetype0 (sine triangle) are allowed with the signbit output. That's fine. You have dds0_out1_wavtype_available and dds0_out0_wavetype_available to say what is possible for each of the two outputs of dds0. > > >>> It can be enabled/disabled while the DDS generates a sine wave on the >>> main output. >>> >>> On the AD9833 the signbit square wave feature is routed to the DDS >> main output. >> Then that part just has the dds0_wavetype (triangle sine square) as >> suggested above. > > That's how I implemented it for the AD9833 Excellent, I had missed that. > > Greetings, > Michael > > -- > Analog Devices GmbH Wilhelm-Wagenfeld-Str. 6 80807 Muenchen > Sitz der Gesellschaft Muenchen, Registergericht Muenchen HRB 4036 > Geschaeftsfuehrer Thomas Wessel, William A. Martin, Margaret Seif > > >