From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH 2/2] gpio: sch: Add interrupt support Date: Fri, 26 Apr 2019 20:44:36 +0300 Message-ID: References: <292e6eff-82cc-6e4d-925b-77a60399e2e0@siemens.com> <20190424100130.GB2654@lahna.fi.intel.com> <1200464b-f969-ebc2-ae82-1f8ca98aaca1@siemens.com> <20190424103306.GC2654@lahna.fi.intel.com> <9377620b-d74a-04d9-a51e-8590400b1c0f@siemens.com> <20190426130615.GT9224@smile.fi.intel.com> <2f3da791-4a10-c2c4-dc5a-22ad16ed7be6@siemens.com> <20190426173329.GA31161@Mani-XPS-13-9360> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <20190426173329.GA31161@Mani-XPS-13-9360> Sender: linux-kernel-owner@vger.kernel.org To: Manivannan Sadhasivam Cc: Jan Kiszka , "Enrico Weigelt, metux IT consult" , Andy Shevchenko , Mika Westerberg , Linus Walleij , Bartosz Golaszewski , Linux Kernel Mailing List , "open list:GPIO SUBSYSTEM" , ACPI Devel Maling List , "Rafael J. Wysocki" List-Id: linux-gpio@vger.kernel.org On Fri, Apr 26, 2019 at 8:33 PM Manivannan Sadhasivam wrote: > On Fri, Apr 26, 2019 at 08:20:19PM +0300, Andy Shevchenko wrote: > > On Fri, Apr 26, 2019 at 7:05 PM Jan Kiszka wrote: > > > On 26.04.19 16:42, Enrico Weigelt, metux IT consult wrote: > > > > On 26.04.19 15:36, Jan Kiszka wrote: > > The problem here is opaque number. This has to be chip + *relative* pin number/ > > See this: > > https://stackoverflow.com/questions/55532410/how-do-linux-gpio-numbers-get-their-values/55579640#55579640 > > > > But for platform like 96Boards we don't need controller specific lookup, these > are all handled by the platform code [1] so that the users can use the standard > pinout number to access GPIOs. This is a complete mistake. There is *no* global GPIO numbers anymore in Linux. (I don't count very old legacy platforms) Read above, it applies to DT or whatever resource provider. > For instance, pin 23 on the Low Speed expansion > header is the GPIO for all 96Boards platform, so the user can access that pin > using 23 itself in the application and it will run across all supported > 96Boards. > > That's one of the reason why we prefer MRAA. > [1] https://github.com/intel-iot-devkit/mraa/blob/master/src/arm/96boards.c#L75 -- With Best Regards, Andy Shevchenko