Re: ABS_MAX incrementation?

[Daniel Mack <daniel@caiaq.de>]

Hi Dmitry,

On Mon, May 03, 2010 at 11:58:32PM -0700, Dmitry Torokhov wrote:
> On Sun, May 02, 2010 at 02:13:31PM +0200, Daniel Mack wrote:
> > Hmm, maybe I could also help with that. Could you outline where this
> > should go? I guess a linked list is not very suitable as it doesn't
> > allow instant access of specific members. So we need a fixed-size bitmap
> > to indicate active members at least?
> 
> I was just thinking about having drivers taht emit absolute events
> allocate abs data (value, min, max, resolution) separately from
> allocating a device (or maybe have additional input_abs_device_alloc
> helper). Someting very simple.

So that would buy us less memory footprint by saving 4 integers for 1
pointer. However, we would still need to store an array of pointers
which has ABS_MAX entries.

I'm hessitating as I would like to see ABS_MAX being quite large.
I'm planning to write a driver with > 100 absolute axis soon.

Also, that approach wouldn't be able to be descriptive about what the
axis in fact represent, and especially for such a high number, that
would be more than just a nice-to-have :)

As I say, I'd be willing to help with this hack up a clean solution
which also teaches the user space interface new fancy features. I would
just need some idea what's a proper way to go.

Thanks,
Daniel