On 03/19/2014 08:02 AM, Benjamin Tissoires wrote:

On 03/18/2014 09:03 PM, Christopher Heiny wrote:

quoted

Even if the RMI4 touchscreen/touchpad provides reporting both
relative and absolute coordinates, reporting both to userspace
could be confusing. Allow the platform data to disable either
absolute or relative coordinates.

General comments on the patch:
Is there really a need to export the rel axis when there is already an
abs collection?
I mean, with the RMI4 over HID over I2C found on the XPS Haswell series,
RMI4 will be bound automatically, and the sensor may (will) pretend that
it can do both abs and rel. However, we are not using a platform_data
for them (I think we should not), and we will get the two collections.

I would personally be in favor of having a priority mechanism: if abs is
here, skip rel, otherwise use rel. But I have no clue if you will ship
devices which will require both. So you make the call.

Hi Benjamin,

That's a great idea.  I'm a tad embarrassed we didn't think of that 
approach.

We do ship products with both abs and rel enabled.  We'll implement the 
abs-priority approach, but also keep the platform data (or device tree, 
once that's implemented) top optionally disable abs reporting, because 
it's very handy to have during new system bring up and certain 
prototyping use cases.

As before, I'll let Andrew handle the code specific comments.

					Cheers,
						Chris

[snip]