From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932944AbbA3Ptz (ORCPT ); Fri, 30 Jan 2015 10:49:55 -0500 Received: from pandora.arm.linux.org.uk ([78.32.30.218]:36912 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932844AbbA3Ptw (ORCPT ); Fri, 30 Jan 2015 10:49:52 -0500 Date: Fri, 30 Jan 2015 15:49:26 +0000 From: Russell King - ARM Linux To: Peter Hurley Cc: Thierry Reding , Varka Bhadram , Chunyan Zhang , gregkh@linuxfoundation.org, mark.rutland@arm.com, gnomes@lxorguk.ukuu.org.uk, heiko@sntech.de, andrew@lunn.ch, jslaby@suse.cz, lanqing.liu@spreadtrum.com, pawel.moll@arm.com, zhang.lyra@gmail.com, zhizhou.zhang@spreadtrum.com, geng.ren@spreadtrum.com, antonynpavlov@gmail.com, linux-serial@vger.kernel.org, grant.likely@linaro.org, orsonzhai@gmail.com, florian.vaussard@epfl.ch, devicetree@vger.kernel.org, jason@lakedaemon.net, arnd@arndb.de, ijc+devicetree@hellion.org.uk, hytszk@gmail.com, robh+dt@kernel.org, wei.qiao@spreadtrum.com, linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, galak@codeaurora.org, shawn.guo@linaro.org Subject: Re: [PATCH v10 2/2] tty/serial: Add Spreadtrum sc9836-uart driver support Message-ID: <20150130154926.GN26493@n2100.arm.linux.org.uk> References: <1422443324-25082-1-git-send-email-chunyan.zhang@spreadtrum.com> <1422443324-25082-3-git-send-email-chunyan.zhang@spreadtrum.com> <54CA5128.8050500@gmail.com> <54CA568E.6080306@hurleysoftware.com> <20150129160553.GC26493@n2100.arm.linux.org.uk> <20150130101838.GC16744@ulmo> <54CB72F7.8060706@hurleysoftware.com> <20150130140854.GJ26493@n2100.arm.linux.org.uk> <54CBA426.7050900@hurleysoftware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <54CBA426.7050900@hurleysoftware.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 30, 2015 at 10:32:54AM -0500, Peter Hurley wrote: > Before you say consistency, I think you should look at the stats below. > IOW, if you want to change the error code return from probe() for > consistency's sake, a tree-wide patch would be the appropriate way. Now look outside the serial driver sub-tree. There are 1234 instances of platform_get_resource(, IORESOURCE_MEM, ) in the drivers/ sub-tree, with 700 instances of devm_ioremap_resource() being used there. Of the devm_ioremap_resource() instances: - 555 use platform_get_resource() in the preceding two lines - which is not enough to do anything but rely on the -EINVAL return value. - 16 mention ENODEV in the preceding three lines. There are 132 which use platform_get_resource() and return ENODEV within the following three lines (which may intersect with the above 16 number) and 88 which use EINVAL. So, there are in total 643 instances where a missing resource returns EINVAL, and between 132 and 148 instances which return ENODEV. Yes, 643 + 148 isn't 1234, but I'm not going to read through all 1234 locations just for the sake of this thread. What's clear though is that more than 50% of sites using platform_get_resource(, IORESOURCE_MEM, ) return EINVAL for the lack of a resource. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net.