Re: NetBSD 9.1 amd64 base X11: hypersensitive touchpad

[mlelstv%serpens.de@localhost (Michael van Elst)]

mayuresh%acm.org@localhost (Mayuresh) writes:

>On Mon, Apr 12, 2021 at 05:16:37AM -0000, Michael van Elst wrote:
>> >options     PMS_SYNAPTICS_TOUCHPAD  # Enable support for Synaptics Touchpads
>> 
>> It's a compile-time option for the pms driver to include code that
>> handles Synaptics Touchpads.

>So I can assume synaptics support is compiled in. So why doesn't sysctl -a
>show the synaptics options mentioned in man pms? Is there any alternative
>way to cross check whether option is compiled into the running kernel?

A kernel can have the config embedded, and 'config -x' will dump that
config.

 config -x | grep SYNAP
options         PMS_SYNAPTICS_TOUCHPAD  # Enable support for Synaptics Touchpads

ident will extract compiled-in RCS/CVS tags from a binary.

 ident /netbsd | grep synap
     $NetBSD: synaptics.c,v 1.70 2020/10/01 17:13:19 nia Exp $

nm will reveal linker symbols

 nm /netbsd | grep synap | grep T
ffffffff8042a04c T pms_synaptics_enable
ffffffff80428d7a T pms_synaptics_probe_init
ffffffff8042a18c T pms_synaptics_resume


The sysctl nodes however are only created if the driver actually
finds a synaptics touchpad.

You can boot a kernel with '-x' option to enable debug messages.
A failed synaptics detection then should print:

pms0: synaptics_probe: Not synaptics

A successful synaptics detection prints (also without debug) e.g.:

pms0: Synaptics touchpad version 7.2

But if further initialization goes wrong you also get

pms0: synaptics_probe: Failed to query capabilities.

then you also do not get the sysctl nodes.

You can see how it works in the pms_synaptics_probe_init() function.


My guess is that the Focaltech touchpad which isn't a Synaptics
touchpad is not compatible enough to be treated like one. Google
returns lots of hits of Windows and Linux users that have a similar
issue (i.e. Focaltech not being Synaptics compatible so that
Synaptics tools and drivers don't work).

Linux has a dedicated Focaltech mouse/touchpad driver. It's possible
that this reveals enough information to add support to our mouse
driver just like we support devices from Synaptics, Elan and ALPS.



Greetings,