On Fri, Jul 13, 2012 at 07:30:42PM -1000, Mitch Bradley wrote: > > I'm not sure this is really a good use of aliases. UARTs use aliases > > because it is important that the UART number to tty number is known and > > fixed. > > This brings up an issue that I've been meaning to comment on. > > The use of phandle-valued properties in the aliases node causes real OFW > implementations some amount of heartburn. The Open Firmware standard > says that the properties in /aliases are string-valued. That's > important, because aliases are shorthand for fragments of full device > specifiers (pathnames that can include arguments to nodes). Phandles > can point to nodes, but can't be relative, and can't encode > per-node-component arguments. Um, so, properties in /aliases should not have phandle values, flat tree or otherwise. Has this been seen in the wild, or are you being misled by the fact that dtc's reference-to-phandle and reference-to-path syntax is very similar: prop = <&fred>; Will generate a phandle valued property, but prop = &fred; Will generate a string (path) valued property. > For binding a Linux unit number to a device node, I would prefer to > decorate the node with a property like "linux,unit#", instead of > breaking the standard semantics of /aliases. I don't see how using aliases for unit numbering (inherently) breaks the semantics of /aliases. If phandle valued properties are being used that is wrong, but it's not necessary for the unit numbering anyway. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
