On Sat, May 22, 2010 at 04:52:29PM -0400, Chase Douglas wrote: > On Sat, 2010-05-22 at 19:47 +0200, Henrik Rydberg wrote: > > Chase Douglas wrote: > > > On Sat, 2010-05-22 at 12:38 +0200, Henrik Rydberg wrote: > > >> Getting serious, it is anyone's guess what will happen next, but I was picturing > > >> a table, with a large multitouch screen and buttons along the side of the table. > > >> Sure, we can do "ABS_BTN_0", "ABS_BTN_1", etc, but with slots in place, it seems > > >> more natural to use something like "ABS_MT_BTN_X". While at it, REL_MT event > > >> makes sense for those touchscreen techniques which register changes, like > > >> acoustic pulse recognition. > > > > s/ABS/KEY/ > > > > > > > > Shouldn't this be handled in userspace? I don't think we want to be > > > quirking drivers for instances where the same touchscreen is overlaid on > > > buttons in some cases, but not in others. If we don't quirk, we'd need > > > some mechanism to tell the driver about such buttons. > > > > Perhaps you would like to clarify what "this" means here, and how you arrive at > > quirking drivers. > > I'm arriving rather late to the conversation, so this could be a matter > of me not understanding everything. What I thought you were proposing is > something like what I have on my Nexus One: an MT area encompassing a > touchscreen and extending to an area of four "buttons" off the bottom of > the screen. I was thinking that interactions with these buttons would > trigger the KEY_MT_BTN events you mentioned. However, if thats the case > then the driver needs to know of these buttons, so we've gone from a > dumb touchscreen driver to a driver that must be aware of regions of the > screen where there are buttons. This is where I think it would be better > to have a userspace application (X?) understand the properties of the > screen to know exactly what a touch means, instead of trying to > interpret it inside the kernel. > Even if kernel driver would be doing the "key" decoding then you would not need KEY_MT_BTN - input layer will happily handle several keys pressed at once, so the driver would just emit KEY_WWW, KEY_HOMEPAGE, KEY_CANCEL, etc, etc. No need to bring in MT protocol here. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
