On Mon, Sep 29, 2014 at 04:55:17PM +0100, Mark Brown wrote:

On Mon, Sep 29, 2014 at 03:47:15PM +0200, Thierry Reding wrote:

[...]

quoted

The same thing is going to happen with simplefb for your device. If you
later realize that you need a regulator to keep the panel going, you'll
have to add code to your firmware to populate the corresponding
properties, otherwise the regulator will end up unused and will be
automatically disabled. At the same time you're going to break upstream
for all users of your old firmware because it doesn't add that property
yet.

quoted

And the same will continue to happen for every new type of resource
you're going to add.

So long as we're ensuring that when we don't start supporting resources
without DT additions or at least require DT additions to actively manage
them (which can then include simplefb hookup) we should be fine.

I'm not sure I understand what you mean. If we add a driver for the PMIC
that exposes these regulators and then add a DT node for the PMIC, we'd
still need to fix the firmware to generate the appropriate DT properties
to allow simplefb to enable the regulators.

So unless firmware is updated at the same time, regulators will get
disabled because they are unused.

Thierry
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