From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754248AbcDKQs5 (ORCPT ); Mon, 11 Apr 2016 12:48:57 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:56294 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753862AbcDKQsy (ORCPT ); Mon, 11 Apr 2016 12:48:54 -0400 Subject: Re: [PATCH 1/1] iio: adc: Add driver for the TI INA3221 Triple Current/Voltage Monitor To: Guenter Roeck References: <1460139580-11865-1-git-send-email-afd@ti.com> <570A3FB2.7000600@kernel.org> <570BC74B.3000208@ti.com> <20160411163843.GA27218@roeck-us.net> CC: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald , Marc Titinger , , , Jean Delvare , From: "Andrew F. Davis" Message-ID: <570BD530.8060508@ti.com> Date: Mon, 11 Apr 2016 11:47:44 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <20160411163843.GA27218@roeck-us.net> 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 04/11/2016 11:38 AM, Guenter Roeck wrote: > On Mon, Apr 11, 2016 at 10:48:27AM -0500, Andrew F. Davis wrote: >> On 04/10/2016 06:57 AM, Jonathan Cameron wrote: >>> On 08/04/16 19:19, Andrew F. Davis wrote: >>>> The INA3221 is a three-channel, high-side current and bus voltage monitor >>>> with an I2C and SMBUS compatible interface. >>>> >>>> Signed-off-by: Andrew F. Davis >>> Hi Andrew, >>> >>> My immediate thought on this one is whether it would be better off in hwmon. >>> I'm not convinced either way from a quick glance at the data sheet, but the >>> question needs to be addressed. >>> >> >> I was on the fence with this also, I was leaning towards hwmod until I >> looked onto how the ina2xx driver has been ported to iio. This is almost >> the same part but the ina3x has three monitors vs one. In addition it >> looks like NVIDIA has written a hwmod driver for this part >> (https://github.com/Bogdacutu/STLinux-Kernel/blob/master/drivers/hwmon/ina3221.c) >> but then also ported it over to IIO (although doesn't appear to be >> upstream ready or ever has been submitted for such) >> (https://github.com/SuperPichu/shield-tablet-kernel/blob/master/drivers/staging/iio/meter/ina3221.c) >> So I figured this was the way things are moving, but I have no problem >> working this as a hwmod driver. The IIO work is already done here, I'll >> write the hwmod version also but keep working this, I see no reason we >> cant have both if needed. (unless using this and just using iio_hwmod.c >> if needed is more acceptable?) >> > > You can not have both since they would conflict with each other. > ina2xx has possibly created a bad precedent. I am not inclined to accept > a hwmon driver if an iio driver already exists. If you want an iio driver, > fine with me, but then you (and its users) will have to live with its > limitations when it comes to hardware monitoring. > Hmm, my plan was an MFD device core, that then could mediate the two sub-drivers, but I'm not sure about this yet. > I don't really mind if things are going all towards iio if that is where > the community wants to go. However, if that is the case, I would suggest > that someone should spend the time to define a clear sense of 'limits' > as well as alert handling in iio, in a way that is exportable to other > subsystems (hwmon and thermal come into mind). > I agree. I think both frameworks offer useful interfaces, so I would hate to limit users to one, but for now I'll just post the hwmon version here in a bit and live with that until someone requests the IIO support. Andrew