[PATCH] hid: asus: ROG NKey: Ignore portion of 0x5a report

From: Josh Kilmer <srjek2@gmail.com>
To: linux-kernel@vger.kernel.org
Cc: linux-input@vger.kernel.org, Jiri Kosina <jikos@kernel.org>,
	Benjamin Tissoires <benjamin.tissoires@redhat.com>,
	Josh Kilmer <srjek2@gmail.com>
Subject: [PATCH] hid: asus: ROG NKey: Ignore portion of 0x5a report
Date: Mon, 14 Mar 2022 11:15:50 -0500	[thread overview]
Message-ID: <CAMXW6=97T1tzT=FSyzZN6jBAKgzUDOjqRoH-FMAPLHk1gsD=mA@mail.gmail.com> (raw)

On an Asus G513QY, of the 5 bytes in a 0x5a report, only the first byte
is a meaningful keycode. The other bytes are zeroed out or hold garbage
from the last packet sent to the keyboard.

This patch fixes up the report descriptor for this event so that the
general hid code will only process 1 byte for keycodes, avoiding
spurious key events and unmapped Asus vendor usagepage code warnings.

Signed-off-by: Josh Kilmer <srjek2@gmail.com>
---
 drivers/hid/hid-asus.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index 08c9a9a60ae4..73fb9fc0701c 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -1212,6 +1212,14 @@ static __u8 *asus_report_fixup(struct
hid_device *hdev, __u8 *rdesc,
        rdesc = new_rdesc;
    }

+   if (drvdata->quirks & QUIRK_ROG_NKEY_KEYBOARD &&
+           *rsize == 331 && rdesc[190] == 0x85 && rdesc[191] == 0x5a &&
+           rdesc[204] == 0x95 && rdesc[205] == 0x05) {
+       hid_info(hdev, "Fixing up Asus N-KEY keyb report descriptor\n");
+       // On the 0x5A input report, change count from 5 to 1
+       rdesc[205] = 0x01;
+   }
+
    return rdesc;
 }

-- 
2.35.1
