From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH 38/42] drivers: gpio: vr41xx: use devm_platform_ioremap_resource() Date: Tue, 12 Mar 2019 09:02:32 -0700 Message-ID: <18445a6d-09b2-f2d1-fd7b-4dfbbaf99981@gmail.com> References: <1552330521-4276-1-git-send-email-info@metux.net> <1552330521-4276-38-git-send-email-info@metux.net> <20190312113732.GG31026@ulmo> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: "Enrico Weigelt, metux IT consult" , Thierry Reding , "Enrico Weigelt, metux IT consult" Cc: linux-kernel@vger.kernel.org, linus.walleij@linaro.org, bgolaszewski@baylibre.com, andrew@aj.id.au, sbranden@broadcom.com, bcm-kernel-feedback-list@broadcom.com, hoan@os.amperecomputing.com, orsonzhai@gmail.com, baolin.wang@linaro.org, zhang.lyra@gmail.com, keguang.zhang@gmail.com, vz@mleia.com, matthias.bgg@gmail.com, grygorii.strashko@ti.com, ssantosh@kernel.org, khilman@kernel.org, robert.jarzmik@free.fr, yamada.masahiro@socionext.com, jun.nie@linaro.org, shawnguo@kernel.org, linux-gpio@vger.kernel.org, linux-mips@vger.kernel.org, linux-pwm@vger.kernel.org, linux-omap@vger.kernel.org, linux-tegra@vger.kernel.org List-Id: linux-gpio@vger.kernel.org On 3/12/2019 8:42 AM, Enrico Weigelt, metux IT consult wrote: > On 12.03.19 12:37, Thierry Reding wrote: > >> The driver currently doesn't request the memory described in the >> resource, so technically you're changing behaviour here and with your >> change the driver could now fail if somebody else has already claimed >> the memory. > > hmm, using w/o requesting/claiming - isn't that a bug ? Not necessarily, before regmap existed, you could have very well delegated a subset of a larger resource to a specific driver while a driver requesting that larger resource would be responsible for doing the request_mem_region(). As long as both drivers don't stomp on each other, this is a perfectly valid way to delegate, yet keep things modular/separate. -- Florian