From 3c2b0dbd69901b71848c83d5c642be290198aa13 Mon Sep 17 00:00:00 2001
From: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Date: Thu, 3 Feb 2022 15:32:18 +0100
Subject: [PATCH] HID: input: tag touchscreens as such if the physical is not
 there

Some devices (Elan, Synaptics...) are sometimes not setting a physical
in their finger collections. hid-input will consider them to be pen
devices, leading to some wrong behavior in user space.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Ping Cheng <ping.cheng@wacom.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
---
 drivers/hid/hid-input.c | 29 +++++++++++++++++++++++++----
 1 file changed, 25 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 112901d2d8d2..d2562497a726 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -828,10 +828,31 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 			break;
 
 		case 0x32: /* InRange */
-			switch (field->physical & 0xff) {
-			case 0x21: map_key(BTN_TOOL_MOUSE); break;
-			case 0x22: map_key(BTN_TOOL_FINGER); break;
-			default: map_key(BTN_TOOL_PEN); break;
+			switch (field->physical) {
+			case HID_DG_PUCK:
+				map_key(BTN_TOOL_MOUSE);
+				break;
+			case HID_DG_FINGER:
+				map_key(BTN_TOOL_FINGER);
+				break;
+			default:
+				/*
+				 * If the physical is not given,
+				 * rely on the application.
+				 */
+				if (!field->physical) {
+					switch (field->application) {
+					case HID_DG_TOUCHSCREEN:
+					case HID_DG_TOUCHPAD:
+						map_key_clear(BTN_TOOL_FINGER);
+						break;
+					default:
+						map_key_clear(BTN_TOOL_PEN);
+					}
+				} else {
+					map_key(BTN_TOOL_PEN);
+				}
+				break;
 			}
 			break;