On Thu, Aug 5, 2010 at 12:18 PM, Mark Brown broonie@opensource.wolfsonmicro.com wrote:
It also seems like busy work for users to have to add things like this to their device trees. I think what I'd expect to see in a strongly device tree model is something like the tree for a board saying it's using a given SoC and then a standard device tree for the SoC which is shared between all the different users of that SoC getting merged in early in boot (probably from the kernel). That way if we gain support for a new feature on the SoC or discover something that needs to be flagged up for workaround then every board using the SoC will pick it up. This seems particularly useful for things like crypto engines that are physically internal to the SoC and so don't normally require per-board hookup. In ASoC terms you do need board specific hookup so that's a bit less of an issue but it looses us some of the benefit of having standard chip drivers by pushing some of the chip generic knowledge into a per-machine location.
The lack of shared soc data in device trees is indeed a problem that has been on my radar for a while now. Fortunately I do have a solution[1] which is partially implemented plus a contractual obligation to deliver it to a client in the near future. I fully expect this will become a non-issue between now and about mid November.
g.
[1] http://www.mail-archive.com/devicetree-discuss@lists.ozlabs.org/msg00680.htm...