Hi! Thanks for both answers. To recall the context: >PRODUCT=3/3eb/840b/111 >NAME="Atmel Atmel maXTouch Digitizer Pen" > >Playing with evtest, it appears that the kernel reports the X coordinate >in ABS_X and in ABS_Y, while the Y coordinate goes into ABS_Z and ABS_RX; > I have already seen this Atmel panel, and the problem was that they used > twice X then twice Y to report coordinates: > > diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c > index 2619f7f..b70d4c3 100644 > --- a/drivers/hid/hid-input.c > +++ b/drivers/hid/hid-input.c > @@ -603,7 +603,7 @@ static void hidinput_configure_usage(struct hid_input > *hidinput, struct hid_fiel if (field->flags & HID_MAIN_ITEM_RELATIVE) > map_rel(usage->hid & 0xf); > else > - map_abs(usage->hid & 0xf); > + map_abs_clear(usage->hid & 0xf); > break; > > case HID_GD_HATSWITCH: Yep, this patch helps. It helps a lot. the ABS_X and ABS_Y coordinates are now correct, the ABS_Z and ABS_RX coordinates are gone, I can point and click with the pen. However, things do not work totally as expected, and the pen remains unusable for many drawing applications. I am not sure if the problem lies in the input/hid system, or in Xorg's evdev driver or in the applications, but the problem I am about to describe occurs only with the pen: everything works as expected with the touchpad (recognized as a simple mouse) or with the finger on the touchscreen: * when I try to make annotations with okular with the "draw a freehand line" tool, the line I draw with the pen jumps (drawing a straight line) to some apparently random point outside okular's window and jumps back (drawing another straight line) to where the pen is, several times per second. I don't want to send a jpg to the whole mailing list, but I can send a snapshot on a private email on request. * when I try to use a drawing tool with gimp or mypaint, each time I raise the pen and put it at some other place to make another drawing, a straight line is drawn between the last and the new position of the pen. Here is what happens on evtest if I touch the screen with the pen, move a bit and stops touching; I didn't see anything suspicious, except maybe that sometimes there is a single ABS_X or a single ABS_Y without the other coordinate between two SYN_REPORT. Event: time 1406710046.690615, type 1 (EV_KEY), code 320 (BTN_TOOL_PEN), value 1 Event: time 1406710046.690615, type 3 (EV_ABS), code 0 (ABS_X), value 3279 Event: time 1406710046.690615, type 3 (EV_ABS), code 1 (ABS_Y), value 2555 Event: time 1406710046.690615, -------------- SYN_REPORT ------------ Event: time 1406710046.697616, type 4 (EV_MSC), code 4 (MSC_SCAN), value d0042 Event: time 1406710046.697616, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 1 Event: time 1406710046.697616, -------------- SYN_REPORT ------------ Event: time 1406710046.713550, type 3 (EV_ABS), code 0 (ABS_X), value 3287 Event: time 1406710046.713550, type 3 (EV_ABS), code 1 (ABS_Y), value 2539 [ Many other EV_ABS events] Event: time 1406710047.317556, type 3 (EV_ABS), code 0 (ABS_X), value 3755 Event: time 1406710047.317556, type 3 (EV_ABS), code 1 (ABS_Y), value 1699 Event: time 1406710047.317556, -------------- SYN_REPORT ------------ Event: time 1406710047.340556, type 4 (EV_MSC), code 4 (MSC_SCAN), value d0042 Event: time 1406710047.340556, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 0 Event: time 1406710047.340556, -------------- SYN_REPORT ------------ Event: time 1406710047.342504, type 1 (EV_KEY), code 320 (BTN_TOOL_PEN), value 0 Event: time 1406710047.342504, -------------- SYN_REPORT ------------ Thanks again for the patch, Éric Brunet -- 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