Re: 答复: 答复: 答复: [PATCH] input: alps-fix the issue the special alps trackpoint do not work.

[Hui Wang <hui.wang@canonical.com>]

On 2019/5/23 下午2:01, Peter Hutterer wrote:
> On Wed, May 22, 2019 at 09:40:30AM +0200, Pali Rohár wrote:
>> On Wednesday 22 May 2019 07:30:43 Xiaoxiao Liu wrote:
>>> Hi Pali,
>>>
>>> Ok, and cannot you set ALPS_DUALPOINT flag based on that
>>> alps_check_is_trackpoint() result and then update
>>> alps_process_packet_ss4_v3() code to supports also
>>> V8 trackpoint packets?
>>> --> Yes, we can do like so, when we use the v8 method to process the trackpoint , the mouse speed is not ideal.
>>>        Then we choose the standard mouse driver.
>> Mouse speed is something which is configurable. Have you configured it
>> somehow? Also there is libinput project should handle these settings
>> more properly.
>>
>> Adding Peter Hutterer, maintainer of libinput to loop. I think he could
>> help with this problem.
> libinput has a quirk for a magic multiplier on trackpoints. it was the only
> solution I found that came close to "working" given that every device seems
> to provide some other random magic data. Doc for it is here:
> https://wayland.freedesktop.org/libinput/doc/latest/trackpoint-configuration.html

Hello Peter Hutterer,

To adjust the trackpoint speed from userspace:

If the libinput version is lower than 1.9.0, we could set 
POINTINGSTICK_CONST_ACCEL=0.25

If the libinput version is higher than 1.12.0, we could set 
AttrTrackpointMultiplier=0.25

But if we use libinput-1.10.0,  how could we adjust the speed?

Many thanks in advance.

Hui.


>
> There are also different speeds depending on which xorg driver you'd use (or
> libinput/Wayland), so a "mouse speed is not ideal" is almost a guarantee,
> given a large enough variety of setups :) That's why we have the speed
> toggle, but I'm happy to hear any suggestions on how to make the trackpoint
> more useful (in libinput anyway).
>
>> I do not think it is a good idea to force back to generic PS/2 mouse
>> driver for touchpads and trackpoints. Native drivers for touchpads and
>> trackpoints supports multitouch, absolute reporting and lot of other
>> things... Also calculation of mouse speed from absolute positions on
>> touchpads can be more easily fixed as from emulated relative movements.
> Yeah, agree. Using PS/2 mouse drivers means you lose *all* the extra
> features touchpads have like palm detection, tapping, scrolling, gestures,
> etc.
>
> Cheers,
>     Peter
>
>> Dmitry, what is your opinion about this problem? What should psmouse.ko
>> do in this situation? Disallow usage of absolute mode and force bare
>> PS/2 relative mode?
>