From mboxrd@z Thu Jan 1 00:00:00 1970 From: u.kleine-koenig@pengutronix.de (Uwe =?iso-8859-1?Q?Kleine-K=F6nig?=) Date: Sun, 19 Jun 2016 03:08:23 +0200 Subject: [PATCH] gpio: omap: make gpio numbering deterministical by using of aliases In-Reply-To: References: <1465898604-16294-1-git-send-email-u.kleine-koenig@pengutronix.de> <20160615072404.GB26768@pengutronix.de> Message-ID: <20160619010823.GC26875@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello Linus, On Sat, Jun 18, 2016 at 10:25:45AM +0200, Linus Walleij wrote: > On Wed, Jun 15, 2016 at 9:24 AM, Uwe Kleine-K?nig > wrote: > > On Wed, Jun 15, 2016 at 08:56:58AM +0200, Linus Walleij wrote: > > >> The GPIO numbering scheme is a matter of Linux internals and > >> not about hardware description IMO. > > > > Not sure if I should agree here or not. It's very usual that the > > "internal" gpio numbers match the hardware reference manual. I know this > > from imx, at91, all pre-dt platforms, I'm sure there are more, and I bet > > I'm not the only one relying on this for omap. > > I think it will still match nicely against the chip-local offsets of the > primary gpiochip so it'll be fine with a chardev too. The same was/is I cannot follow. What is the primary gpiochip? The first one? What is a "chip-local offset". Just 3 for the fourth gpio of a given gpio bank? I guess the problem is that I didn't follow development of the gpio chardev. > the case of the first interrupts on x86 I think, but with the plethora of > irqchips and dependency on probe order etc the assumption is > nowadays to dangerous. > > > > > And this is very usual in the dt world, too: > > > > $ git grep -El 'gpio. = \&gpio' arch/arm/boot/dts | wc -l > > 37 > > Aha I didn't even know. Well I guess I could allow it for OMAP too > then, but I want an ACK from one of the DT binding maintainers. I added Rob, Frank, Mark and the device tree list to the recipients of this mail. Can you please comment? There is already a v2 that you can find at http://thread.gmane.org/gmane.linux.kernel.gpio/17399/ in case it didn't hit your mailbox. If you tell me that you want it, I can also bounce you the series. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-K?nig | Industrial Linux Solutions | http://www.pengutronix.de/ |