From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Thu, 16 Jul 2015 16:09:42 +0200 Subject: [PATCH 1/2] ARM: ux500: define serial port aliases In-Reply-To: References: <1436520735-23692-1-git-send-email-linus.walleij@linaro.org> <2120032.PN20RpmoKe@wuerfel> Message-ID: <2694937.qjRpGCMvqj@wuerfel> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thursday 16 July 2015 16:03:18 Linus Walleij wrote: > On Tue, Jul 14, 2015 at 10:53 PM, Arnd Bergmann wrote: > > On Monday 13 July 2015 10:21:51 Linus Walleij wrote: > >> > >> Since the original code just defined all three serial ports > >> for all boards by them including ste-dbx500.dtsi I first made > >> the patch to that file, and then as you said it had to be done > >> on a per-toplevel file, I did it in the individual DTS files instead. > > > > I'm not following here. If you have boards that want port 1 to be > > disabled, shouldn't you remove that alias? > > No, that is done by not changing status = "disabled"; to > status = "okay"; on a per-board basis. > > This is what the second patch is doing. > > The aliases are set also to disabled ports to ensure enumeration > for the cases where a board file enabled a previously disabled > UART. > Well, both really. The status property tells the kernel to not ever touch a device, while the alias is what traditionally gets used to assign an OS visible device name to a device in the tree. This is more true for MacOS and AIX than Linux, which sometimes does its own naming, but we really should not have an alias pointing at a disabled device node. Arnd