From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Mon, 4 Jun 2012 14:30:59 +0000 Subject: Kernel 3.4 on Dreamplug: no serial console In-Reply-To: <2396575.dLS9zmzUSD@flexo> References: <20120603184049.GF14756@titan.lakedaemon.net> <2396575.dLS9zmzUSD@flexo> Message-ID: <201206041430.59397.arnd@arndb.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Monday 04 June 2012, Florian Fainelli wrote: > On Sunday 03 June 2012 14:40:49 Jason Cooper wrote: > > On Sun, Jun 03, 2012 at 05:12:18PM +0000, Arnd Bergmann wrote: > > > I'd also accept a patch to make ARCH_KIRKWOOD_DT select OF_SERIAL if > people > > > prefer that, but I think just changing the defconfig is better. > > > > I'd prefer the defconfig as there are situations where users/oems deploy > > a kernel without support for serial console. In order to do that with > > your patch, or similar approaches, they would have to change the code. > > With defconfig, they don't. > > Should not you rather select OF_SERIAL and add a status propery to the uart > node in device tree, so that it is up to dtb provider to determine whether > this device node should be enabled or not? You would avoid all kind of > defconfig issue. Obviously the configuration comes from DT, but there are still reasons to not select the driver. E.g. you might want to build a kernel that runs on a wide variety of systems and has all drivers as loadable modules rather than built-in. There are also some systems that are rather memory constraint and even disable printk support, so the console becomes useless too. Arnd