On Wed, Jul 20, 2011 at 07:04:20PM +0800, Shawn Guo wrote:

quoted

Mostly consistency.  Most of the experience we have with the flattened
device tree up to this point hasn't bothered with the 'status'
property.  It is only when AMP and hypervisors cam online that it
became important to use a status property, and that only when the
kernel needs to be told that the device does indeed exist, but it must
not be touched.  I'd like to continue that pattern for new DT users
with the default assumption that a device is enabled unless the board
.dts explicitly disables it.

[...]

Besides the bothering that we have to list so many unused controllers
in individual board dts file, it's also hard to tell which controllers
are actually available on the board.  People have to look at imx53.dts
to get a full list and then exclude the ones in imx53-<board>.dts as
"disabled".

And if we go the way opposite, adding "disabled" status for everyone
in imx53.dts, we will only need to specify the peripherals that are
actually available on board with "okay" status in imx53-<board>.dts.
And it's much more clear for people to see what peripherals are
available on individual board.

So I'm going the way than you suggested.  Please let me know if you
strongly dislikes it.

Yes, I strongly dislike it.  I understand the concern, but at this
early stage with converting to device tree I think consistency between
platforms is more important.  We can talk about the issue at Linaro
Connect in 2 weeks, but in the mean time please use the
enabled-by-default/explicitly-disabled pattern.

g.