[PATCH 4.12 074/196] HID: multitouch: do not blindly set EV_KEY or EV_ABS bits

[Greg Kroah-Hartman]

4.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>

commit 4cf56a89c696e66d10612b43b7e95852611e76c2 upstream.

Now that input core insists on having dev->absinfo when device claims to
generate EV_ABS in its dev->evbit, we should not be blindly setting that
bit.

The code in question might have been needed before input_set_abs_params()
started setting EV_ABS in device's evbit, but not anymore, and is now
breaking devices such as SMART SPNL-6075 Touchscreen.

Fixes: 6ecfe51b4082 ("Input: refuse to register absolute devices ...")
Reported-by: Matthias Fend <Matthias.Fend@xxxxxxxxxxxxxx>
Tested-by: Matthias Fend <Matthias.Fend@xxxxxxxxxxxxxx>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/hid/hid-multitouch.c |   16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

--- a/drivers/hid/hid-multitouch.c
+++ b/drivers/hid/hid-multitouch.c
@@ -595,16 +595,6 @@ static int mt_touch_input_mapping(struct
 	return 0;
 }
 
-static int mt_touch_input_mapped(struct hid_device *hdev, struct hid_input *hi,
-		struct hid_field *field, struct hid_usage *usage,
-		unsigned long **bit, int *max)
-{
-	if (usage->type == EV_KEY || usage->type == EV_ABS)
-		set_bit(usage->type, hi->input->evbit);
-
-	return -1;
-}
-
 static int mt_compute_slot(struct mt_device *td, struct input_dev *input)
 {
 	__s32 quirks = td->mtclass.quirks;
@@ -905,8 +895,10 @@ static int mt_input_mapped(struct hid_de
 		return 0;
 
 	if (field->application == HID_DG_TOUCHSCREEN ||
-	    field->application == HID_DG_TOUCHPAD)
-		return mt_touch_input_mapped(hdev, hi, field, usage, bit, max);
+	    field->application == HID_DG_TOUCHPAD) {
+		/* We own these mappings, tell hid-input to ignore them */
+		return -1;
+	}
 
 	/* let hid-core decide for the others */
 	return 0;