Messages in this thread | | | Date | Mon, 15 Aug 2005 19:45:58 +0200 | From | Vojtech Pavlik <> | Subject | Re: [PATCH] to drivers/input/evdev.c to add mixer device "/dev/input/events" |
| |
On Mon, Aug 15, 2005 at 11:27:56AM -0600, Joe Peterson wrote:
> I, and a growing number of others, have been having trouble with using > touch screen devices in Linux, particularly the motorized ones that fit > into car dashboards. The problem is that these devices, which have a > USB touchscreen (often the eGalax brand), turn off when the screen is > retracted, causing Linux to remove and/or disconnect the event device > in /dev/input. > > Using udev to assign a persistent symlink to the device was the first > thing I tried, but it does not solve the problem, since X windows does > not see the device when it turns back on, even if it's the same name. I > (and others) have tried hacks like changing virtual terminals, etc. to > get it back, but these are not elegant solutions are are problematic. > > Anyway, I finally decided the thing I needed was something like > /dev/input/mice, since it is always there for X to see, even if the > device is off during boot. But the mousedev devices are not the > right data format for use with the touch screens (you need "event" > ones). So I hacked evdev.c and added "/dev/input/events", which is a > mixer as well and catches all events from event0, event1, etc.
> Anyway, I hope my change is valuable. I (and others) would love to see > it appear in the official kernel source. I attached the patch.
I really think this is the wrong way to go. Much better would be to fix the X driver (are you using evtouch or something else?) to notice the disconnect of the device (it'll get -ENODEV) and connect of the device (a hotplug event is issued, a select() on /proc/bus/input/devices returns as readable) and re-open the device.
It's not really possible to mix the events from all devices together, namely touchscreens, since mixing of ABS_* events is undefined.
-- Vojtech Pavlik SuSE Labs, SuSE CR - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |