From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751865AbbAVK4U (ORCPT ); Thu, 22 Jan 2015 05:56:20 -0500 Received: from mail-ig0-f176.google.com ([209.85.213.176]:51820 "EHLO mail-ig0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751146AbbAVK4L (ORCPT ); Thu, 22 Jan 2015 05:56:11 -0500 Date: Thu, 22 Jan 2015 10:56:05 +0000 From: Lee Jones To: Javier Martinez Canillas Cc: Olof Johansson , Doug Anderson , Bill Richardson , Simon Glass , Gwendal Grignou , Jonathan Corbet , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, arnd@arndb.de Subject: Re: [PATCH RESEND v2 3/7] mfd: cros_ec: Add cros_ec_lpc driver for x86 devices Message-ID: <20150122105605.GB9129@x1> References: <1420205572-2640-1-git-send-email-javier.martinez@collabora.co.uk> <1420205572-2640-4-git-send-email-javier.martinez@collabora.co.uk> <20150120081104.GT21886@x1> <54BE7B08.1010900@collabora.co.uk> <20150120163410.GC30656@x1> <54BE87C4.4040108@collabora.co.uk> <20150122084244.GP22024@x1> <54C0BE21.7020008@collabora.co.uk> <20150122094608.GA5769@x1> <54C0D29C.4010904@collabora.co.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <54C0D29C.4010904@collabora.co.uk> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 22 Jan 2015, Javier Martinez Canillas wrote: > On 01/22/2015 10:46 AM, Lee Jones wrote: > >> > >> But there doesn't seem to be a LPC subsystem in the kernel so we don't have a > >> nice abstraction layer in this case. > > > > This is the crux of the problem. However, I feel bad for MFD, as it > > is, once more, being used as an "well it doesn't fit anywhere else, so > > let's shoehorn it in there" type of dumping ground. > > > Yes, I completely understand your point, is that I didn't think that a ~300 > lines driver was that bad specially since the communication bits that reads > and writes the register is not a complex logic IMHO. This has nothing to do with LoC, it's the principle of the matter. > >> > Are there any other Low Pin Count drivers in the kernel? > >> > > >> > >> I don't know tbh, I didn't even know what LPC was before I picked this patch > >> to push it upstream. I searched in the Linux codebase for other LPC drivers > >> but I didn't find anything, that doesn't mean that it doesn't exist though. > > > > I agree. Perhaps a suitable driver should live in drivers/misc until > > there are enough of them to warrant its own subsystem. > > > > Yes, I can move the driver to drivers/misc if you think that is more suitable > to be there. > > I've taken another look and AFAICT there are two other mfd drivers that use an > LPC bus, these are drivers/mfd/lpc_{i,s}ch.c for Intel's I/O Controller HUB and > System Controller Hub respectively. These looked like PCI aggregates when I looked at them last? -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog