[PATCH] gpio: omap: make gpio numbering deterministical by using of aliases
From: Uwe Kleine-König <hidden>
Date: 2016-06-19 01:08:23
Also in:
linux-devicetree, linux-gpio, linux-omap
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 [off-list ref] wrote:quoted
On Wed, Jun 15, 2016 at 08:56:58AM +0200, Linus Walleij wrote:quoted
quoted
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.quoted
And this is very usual in the dt world, too: $ git grep -El 'gpio. = \&gpio' arch/arm/boot/dts | wc -l 37Aha 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/ |