From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Walleij Subject: Re: [PATCH] gpio: zynq: Setup chip->base based on alias ID Date: Wed, 2 May 2018 15:01:24 +0200 Message-ID: References: <6ee982f8eb6e07f9ecbb0cc5093152f4a16b9c31.1523454899.git.michal.simek@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Michal Simek Cc: "linux-kernel@vger.kernel.org" , Michal Simek , Steffen Trumtrar , Peter Crosthwaite , "open list:GPIO SUBSYSTEM" , Rob Herring , Linux ARM List-Id: linux-gpio@vger.kernel.org On Wed, May 2, 2018 at 12:15 PM, Michal Simek wrote: > On 2.5.2018 12:10, Linus Walleij wrote: >> On Thu, Apr 26, 2018 at 3:35 PM, Michal Simek wrote: >>> Yes, it is about legacy application which I have seen recently and there >>> is no source code for application calls it because board vendor doesn't >>> provide it. >>> >>> You are right that -1 was used from the beginning in mainline but >>> unfortunately this driver was in vendor tree for a while and it uses 0 >>> there. >>> >>> In upstreaming this was changed to -1 but customers have a lot of code >>> which developed against vendor tree and they want to use >>> latest&greatest. And without this they are not able to run that >>> applications. >>> >>> I found that this logic is already in 5 drivers in mainline that's why I >>> send this patch to be +1. >> >> I see. >> >> Sadly comaptibility with out-of-tree driver code is none of our >> (community) business. >> >> We do pay a lot of effort not to break the ABI to userspace, but >> it needs to be an ABI coming from the mainline kernel, not from >> a vendor tree. >> >> So to the mainline kernel this is no regression. > > I understand your statement. On the other hand it is feature which was > permitted in past for some drivers and this is +1. But was it permitted because of breaking out of tree code? I know people have done questionable things in the past, but two wrongs does not make one right. Yours, Linus Walleij From mboxrd@z Thu Jan 1 00:00:00 1970 From: linus.walleij@linaro.org (Linus Walleij) Date: Wed, 2 May 2018 15:01:24 +0200 Subject: [PATCH] gpio: zynq: Setup chip->base based on alias ID In-Reply-To: References: <6ee982f8eb6e07f9ecbb0cc5093152f4a16b9c31.1523454899.git.michal.simek@xilinx.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, May 2, 2018 at 12:15 PM, Michal Simek wrote: > On 2.5.2018 12:10, Linus Walleij wrote: >> On Thu, Apr 26, 2018 at 3:35 PM, Michal Simek wrote: >>> Yes, it is about legacy application which I have seen recently and there >>> is no source code for application calls it because board vendor doesn't >>> provide it. >>> >>> You are right that -1 was used from the beginning in mainline but >>> unfortunately this driver was in vendor tree for a while and it uses 0 >>> there. >>> >>> In upstreaming this was changed to -1 but customers have a lot of code >>> which developed against vendor tree and they want to use >>> latest&greatest. And without this they are not able to run that >>> applications. >>> >>> I found that this logic is already in 5 drivers in mainline that's why I >>> send this patch to be +1. >> >> I see. >> >> Sadly comaptibility with out-of-tree driver code is none of our >> (community) business. >> >> We do pay a lot of effort not to break the ABI to userspace, but >> it needs to be an ABI coming from the mainline kernel, not from >> a vendor tree. >> >> So to the mainline kernel this is no regression. > > I understand your statement. On the other hand it is feature which was > permitted in past for some drivers and this is +1. But was it permitted because of breaking out of tree code? I know people have done questionable things in the past, but two wrongs does not make one right. Yours, Linus Walleij