[PATCH] HID: asus: fix touchpad multitouch initialization regression

[Panz Dev]

In Linux 7.1, commit 7253091766de ("HID: asus: do not abort probe when not necessary")
and commit 0919db9f3583 ("HID: asus: always fully initialize devices")
introduced regressions in the probe sequence for ASUS I2C/HID touchpads
(such as on the ASUS E200HA):

1. asus_start_multitouch() was placed inside the claimed input check block:
     if (drvdata->input && (hdev->claimed & HID_CLAIMED_INPUT))
   On ASUS touchpads, (hdev->claimed & HID_CLAIMED_INPUT) evaluates to
   false during asus_probe(), skipping asus_start_multitouch().

2. The asus_report_id_init loop in asus_probe() was executed unconditionally
   for all devices, which sends keyboard initialization feature requests
   (asus_kbd_init) to touchpad endpoints, corrupting touchpad probe state.

This patch fixes both issues by:
- Skipping keyboard report initialization for touchpad devices (!drvdata->tp).
- Moving asus_start_multitouch() outside the claimed input check block so
  multitouch initialization is always executed for touchpads.

Tested on ASUS E200HA (where touchpad functionality is fully restored)
and ASUS VivoBook Flip 14 TP401MA (confirming zero regressions).

Fixes: 7253091766de ("HID: asus: do not abort probe when not necessary")
Fixes: 0919db9f3583 ("HID: asus: always fully initialize devices")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Panz Dev <panz.development@xxxxxxxxx>
---
 drivers/hid/hid-asus.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index 3f5e96900b67..7f19ca1e5a1b 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -1294,12 +1294,14 @@ static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)
 		return ret;
 	}

-	for (int r = 0; r < ARRAY_SIZE(asus_report_id_init); r++) {
-		if (asus_has_report_id(hdev, asus_report_id_init[r])) {
-			ret = asus_kbd_init(hdev, asus_report_id_init[r]);
-			if (ret < 0)
-				hid_warn(hdev, "Failed to initialize 0x%x: %d.\n",
-					 asus_report_id_init[r], ret);
+	if (!drvdata->tp) {
+		for (int r = 0; r < ARRAY_SIZE(asus_report_id_init); r++) {
+			if (asus_has_report_id(hdev, asus_report_id_init[r])) {
+				ret = asus_kbd_init(hdev, asus_report_id_init[r]);
+				if (ret < 0)
+					hid_warn(hdev, "Failed to initialize 0x%x: %d.\n",
+						 asus_report_id_init[r], ret);
+			}
 		}
 	}

@@ -1327,12 +1329,12 @@ static int asus_probe(struct hid_device *hdev, const struct hid_device_id *id)
 			drvdata->input->name = "Asus TouchPad";
 		else
 			drvdata->input->name = "Asus Keyboard";
+	}

-		if (drvdata->tp) {
-			ret = asus_start_multitouch(hdev);
-			if (ret)
-				goto err_stop_hw;
-		}
+	if (drvdata->tp) {
+		ret = asus_start_multitouch(hdev);
+		if (ret)
+			goto err_stop_hw;
 	}

 	return 0;
-- 
2.47.0