On 03/15/2012 10:56 AM, Thorsten Wissmann wrote: > On Thu, Mar 15, 2012 at 12:27:22PM -0500, Chris Bagwell wrote: >> Its also true that sharing ABS_X/Y events between both a BTN_TOOL_PEN >> and a BTN_TOOL_FINGER will confuse most user land apps (they think >> only touchpads can declare BTN_TOOL_FINGER's but this is a >> touchscreen) and it also has bad side affects to the kernel's MT >> pointer emulation functions. >> >> You can look at kernel drivers/input/touchscreen/wacom_w8001.c for an >> example touchscreen that supports pen and at least 2 MT touches on a >> single /dev/input device (because HW packets come over single serial >> interface). It does not declare a BTN_TOOL_FINGER nor use pointer >> emulation to overcome issues I mentioned and xf86-input-wacom >> understands how to handle this device. >> >> If you want to work with other unmodified user land apps (perhaps >> xf86-input-evdev for touches) then its probably easiest to split pen >> and touch to separate input devices. drivers/input/tablet/wacom_wac.c >> shows some examples of that approach but that driver doesn't have to >> work to hard to split in to 2 input devices because the USB device >> already puts the events on separate USB interfaces. > > OK. We want the device to work with the xf86-input-evdev driver. So we > will split it into two devices. Or you could teach evdev to know how to handle mixed devices :). I think that's the "better" approach over all, but it's up to you. -- Chase -- 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
