[PATCH] Implements new features for updating existing device tree nodes.

David Gibson david at gibson.dropbear.id.au
Mon Oct 18 11:11:35 EST 2010


On Sat, Oct 16, 2010 at 12:32:17PM -0600, Grant Likely wrote:
> On Sat, Oct 16, 2010 at 06:45:47AM -0700, John Bonesio wrote:
> > On Sat, 2010-10-16 at 02:10 -0600, Grant Likely wrote:
> > > On Sat, Oct 16, 2010 at 05:47:44PM +1100, David Gibson wrote:
> > > > On Fri, Oct 15, 2010 at 08:21:17PM -0700, John Bonesio wrote:
[snip]
> > > For example; I could have a labelled spi bus node with child nodes for
> > > each of the spi devices.  I want to be able to remove/replace the
> > > child nodes without having to label them first.
> > > 
> > > g.
> > 
> > Why not just add the label to the node you need first?
> 
> That may not be possible and/or desirable.  For instance, when the
> tree is extracted from /proc.  Or if the base tree in stored in the
> kernel source and an external tool is modifying it for a specific
> purpose (when unable to patch the kernel tree).  Or for generated
> device trees from the Xilinx toolchain for FPGAs.  Modifying the
> source data isn't always an option.

You can apply your overlays by path in this case..

> Plus I want the ability to logically group related changes.  ie.
> delete a device and add a device to the same bus at the same time.
> Or delete a phy node, add a replacement phy node at a different
> address, and update the ethernet phy-device phandle in the same
> block.

Hrm, I really don't think this is a good argument.  You're conflating
the grouping of logically related changes with the tree structure
which I think is a mistake.  Putting the changes in the same file
and/or adjusting your spacing and comments to show the logical
grouping seems less likely to cause other problems.

-- 
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


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