Re: [PATCH 3/3] Input: bu21013_ts - Add support for Device Tree booting

On Thu, Nov 29, 2012 at 12:00:00PM +0000, Lee Jones wrote:

On Thu, 29 Nov 2012, Mark Brown wrote:

quoted

Right, which is why this mostly works, but it's still better to provide
an actual compatible string which we can be 100% certain will avoid
conflicts.  This is very low cost when one is already defining DT
bindings.

I know that it's an easy thing to do, but I'm more worried about
what would happen if the an I2C device is registered using the
current way (stripping the compatible string and using it as a
client look-up) and we also provide a compatible entry in the
driver itself. Do you know if there is any danger of duplicate
registration or suchlike?

That's totally fine, we try first with compatible properties and only
look for the fallback if there aren't any.

quoted

quoted

Hence, there should be no need to have a compatible string in any i2c
driver registration information.

quoted

We're getting away with it at present (and frankly nobody's going to
build in two different drivers for a chip of the same name for practical
systems anyway).

Right. In the same way as we're getting away with it when we
register a platform_device using the register/add routines.

Those are all completely Linux-defined of course which helps as well.