From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ppsw-52.csi.cam.ac.uk ([131.111.8.152]:53137 "EHLO ppsw-52.csi.cam.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752866Ab2EDOmP (ORCPT ); Fri, 4 May 2012 10:42:15 -0400 Message-ID: <4FA3EAC2.2080005@cam.ac.uk> Date: Fri, 04 May 2012 15:42:10 +0100 From: Jonathan Cameron MIME-Version: 1.0 To: "Hennerich, Michael" CC: "jic23@kernel.org" , "linux-iio@vger.kernel.org" , "device-drivers-devel@blackfin.uclinux.org" Subject: Re: [PATCH 3/3] iio: frequency: New driver for AD9523 SPI Low Jitter Clock Generator References: <1336138266-25480-1-git-send-email-michael.hennerich@analog.com> <1336138266-25480-3-git-send-email-michael.hennerich@analog.com> <4FA3DE8E.6050802@cam.ac.uk> <544AC56F16B56944AEC3BD4E3D5917714E797B4F51@LIMKCMBX1.ad.analog.com> In-Reply-To: <544AC56F16B56944AEC3BD4E3D5917714E797B4F51@LIMKCMBX1.ad.analog.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 5/4/2012 3:00 PM, Hennerich, Michael wrote: > Jonathan Cameron wrote on 2012-05-04: >> On 5/4/2012 2:31 PM, michael.hennerich@analog.com wrote: >>> From: Michael Hennerich >> Before I dive in here too far, let me ask the stupid question. >> >> Whilst I know nothing much about it, why is the kernel's clock framework >> unsuitable for this device? > Hi Jonathan, > > I think we had a similar discussion before. > > The in-kernel clock infrastructure HAVE_CLK is not suitable > since it is designed for SoC like systems. > > 1) The API is exported by arch and platform code. > 2) Data structures differ between the different implementations. > 3) Coexistence with other clock providers is by design impossible. > > Greetings, > Michael > Does ring a bell now you mention it :) Thanks for the summary. I can imagine there may be a suggestion to look at overcoming the above in the long term, but can't see it being worth while for a small number of parts.