[PATCH synaptics] Prevent button mashing on clickpads

Daniel Colascione dancol at dancol.org
Thu Oct 31 07:57:49 CET 2013

On 10/30/2013 11:52 PM, Peter Hutterer wrote:
> On Wed, Oct 30, 2013 at 11:39:58PM -0700, Daniel Colascione wrote:
>> On 10/30/2013 11:39 PM, Peter Hutterer wrote:
>>> On Tue, Oct 29, 2013 at 05:08:25PM -0700, Daniel Colascione wrote:
>>>> On 10/29/2013 05:04 PM, Peter Hutterer wrote:
>>>>> On Sun, Oct 27, 2013 at 04:24:47PM -0700, Daniel Colascione wrote:
>>>>>> The tiny patch below disables the clickpad hardware "button" when
>>>>>> syndaemon has asked us to disable tapping.  Without this patch, I
>>>>>> frequently find myself accidentally clicking while typing.
>>>>> isn't this a physical button? if so, it'd be better to just disable the
>>>>> touchpad fully instead of just disabling tapping.
>>>> It's a physical button, but it's unlike other physical buttons in
>>>> that it takes up the _entire trackpad_. It's a lot easier to trigger
>>>> this button than it is to trigger a traditional button, so it really
>>>> should be treated as a tap for disablement purposes.
>>> what device is this? if anything it takes me more effort on my clickpad to
>>> press the whole thing than pressing a button on the old-style clickpad.
>> It's a Lenovo X1 Carbon. All I can do is comment on my annoyance
>> relative to my hardware.
>>>> The idea behind using TOUCHPAD_TAP_OFF instead of TOUCHPAD_OFF is to
>>>> allow the user to move the cursor as soon as possible after typing.
>>> I have no idea what the idea behind it is, the git history isn't forthcoming
>>> here.
>> It's the only reasonable explanation I can think of.
>> my suspicion is that tapping is a separate entity because accidentally
>>> causing a tap/scroll is a problem, moving a bit usually not (especially when
>>> palm detection sucks)
>> Yes.
>>>> By the time the user gets around to actually clicking something, the
>>>> type-inhibit delay will have expired and we'll have turned off
>>>> TOUCHPAD_TAP_OFF. This way, the user never notices the delay ---
>>>> users will take a few hundred ms to click anyway. If we used
>>>> TOUCHPAD_OFF instead, you'd either have to shorten the delay or
>>>> cause users more annoyance.
>>> synaptics history teaches me that you don't get to pick between less or more
>>> annoyance, you only get to choose who you're going to annoy...
>> So you're arguing that all options are equally annoyance, so we
>> shouldn't change anything?
> I'm arguing that if we want to change behaviour that's been there for
> years we better have a really good reason for it. because whenever you
> change some behaviour, you're likely breaking it for someone else.

This machine has only been around for about a year and it has a novel 
clickpad design.

> adding another option is also not really a solution, we have (rough count)
> 69 option and there is almost no testing on the various combinations.
> the driver is almost unmaintainable already, so I'm really hesitant these
> days to add or change anything that's not absolutely required because quite
> frankly, I don't have the time or energy to deal with the fallout.

I'm sorry to hear that you're unwilling to take patches. These patches 
resolve real problems I've had. I now have no choice but to maintain a 
forked version of the driver.

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