Re: [PATCH 1/6] Haptic: add haptic class

From: Trilok Soni
Date: Wed Oct 14 2009 - 06:39:58 EST


Hi Dmitry,

On Wed, Oct 14, 2009 at 1:29 PM, Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
> On Tue, Oct 13, 2009 at 04:43:43PM +0530, Trilok Soni wrote:
>> Hi Kyungmin, Dmitry,
>>
>> On Tue, Oct 13, 2009 at 4:05 PM, Jani Nikula
>> <ext-jani.1.nikula@xxxxxxxxx> wrote:
>> > On Wed, Oct 7, 2009 at 09:17, Kyungmin Park <kyungmin.park@xxxxxxxxxxx> wrote:
>> >> New haptic class support.
>> >> This class handles the haptic devices.
>> >
>> > I'm wondering why a haptic class is needed when there is force
>> > feedback support. Admittedly, I don't know the force feedback
>> > implementation too well, but could someone please enlighten me on
>> > this? Am I missing something here?
>> >
>> > I see haptics as simple force feedback, just with (usually) small
>> > force and short duration. There are devices out there doing haptics
>> > using vibra motors, which I think would be limited if implemented
>> > using this haptics class driver. Would it be somehow problematic
>> > interfacing with the simple haptic hardware using the force feedback
>> > API?
>>
>> Please share your inputs on ff_device usage instead of haptics class.
>> I think Dmitry could add some points here as I don't see much users of
>> ff_device and I don't see any embedded device (like mobile) using it.
>>
>
> Using ff_device was considered when Jiri Slaby was trying to merge
> PHANTOM driver, bit for that device FF infrastructure was too limited
> and this it was decided that phantom would need a special userpsace that
> knows what it is and how to handle it.
>
> The curtrent haptic class seems to be bery limited and may be served via
> FF (constant or other effect in a single direction) but I don't know
> what kind of plans you have to extend it. I guess it warrants another
> discussion.

Probably Kyungmin is the right person to analyze the ff_device
infrastructure in input_device framework and see it fits haptics class
or not. As per me, for the mobile like applications current haptics
class should meet the needs.


--
---Trilok Soni
http://triloksoni.wordpress.com
http://www.linkedin.com/in/triloksoni
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