From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Thu, 13 Sep 2012 10:36:29 +0000 Subject: [PATCH V3 5/5] ARM: bcm2708: instantiate console UART In-Reply-To: <505133CB.1060906@wwwdotorg.org> References: <1347423509-30647-1-git-send-email-swarren@wwwdotorg.org> <201209121045.39999.arnd@arndb.de> <505133CB.1060906@wwwdotorg.org> Message-ID: <201209131036.29929.arnd@arndb.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thursday 13 September 2012, Stephen Warren wrote: > On 09/12/2012 04:45 AM, Arnd Bergmann wrote: > > On Wednesday 12 September 2012, Stephen Warren wrote: > >> From: Simon Arlott > >> > >> This patch was extracted from git://github.com/lp0/linux.git branch > >> rpi-split as of 2012/09/08, and modified as follows: > >> > >> * Modified UART DT node to use a unit-address to differentiate UART node > >> names, rather than using different base names "uart0" and "uart1". > >> Note that UART 1 (the Broadcom "mini UART") is not yet present, but > >> I'm naming the DT node in anticipation that it will be added. > >> > > > > Shouldn't the selection be done using an alias like this? > > > > aliases { > > serial0 = &/uart at 20201000; > > }; > > The "differentiate" was more "ensure that node names in DT are unique" > than anything to do with user-visible selection/identification. > > I can certainly add the alias if you want, but I don't know what benefit > it will have, since I've never used aliases before. The idea of the aliases is that you can identify which port to use if one passes an argument like "console=ttyS0" or opens a specific /dev/tty* device node. I believe we don't actually use it that way at the moment though. Arnd