Re: [patch 1/3] Input: psmouse - create PS/2 protocol options for Kconfig

From: Dmitry Torokhov
Date: Fri Feb 16 2007 - 10:42:57 EST

On 2/16/07, Andres Salomon <dilinger@xxxxxxxxxx> wrote:
Dmitry Torokhov wrote:
> On Thursday 15 February 2007 20:30, Andrew Morton wrote:
>> On Thu, 15 Feb 2007 19:55:29 -0500
>> Andres Salomon <dilinger@xxxxxxxxxx> wrote:
>> Perhaps a nicer implementation would be to have a separate .c file for each
>> variant.
> Having completely separate sub-drivers is very hard because of very delicate
> PS/2 protocol probing....
> What do you think about patch below? It somewhat reduces #ifdef clutter in main
> module moving it in .h files...

Normally, I'm a fan of that sort of thing. However, in this case, I
think it makes sense to have the #ifdefs right in the probe function; at
least for me, it makes it easier to understand what's going on. The
synaptics stuff is especially tricky; with a cursory glance over the
code, one might assume that all the synaptics functions disappear when
CONFIG_MOUSE_PS2_SYNAPTICS is unset. However, if the #ifdef's are in
the probe function, it's pretty clear that some synaptics functions
still get called even when CONFIG_MOUSE_PS2_SYNAPTICS is unset.

Thit is a valid point but #ifdef maze in the middle of already messy
psmouse-extensions() is too much for me. I guess I will just add a
comment explaining that synaptics probing is really special.

Btw, can I get that OLPC patch when you have time?

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