[PATCH 01/18] HID: do not assume HAT Switch logical max < 8

From: Benjamin Tissoires <bentiss@kernel.org>
To: Jiri Kosina <jikos@kernel.org>,
	Benjamin Tissoires <bentiss@kernel.org>,
	 Shuah Khan <shuah@kernel.org>,
	Peter Hutterer <peter.hutterer@who-t.net>
Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org,
	 linux-kselftest@vger.kernel.org
Subject: [PATCH 01/18] HID: do not assume HAT Switch logical max < 8
Date: Wed, 10 Apr 2024 19:19:21 +0200	[thread overview]
Message-ID: <20240410-bpf_sources-v1-1-a8bf16033ef8@kernel.org> (raw)
In-Reply-To: <20240410-bpf_sources-v1-0-a8bf16033ef8@kernel.org>

Turns out that the code can handle a greater range, but the data stored
can not. This is problematic on the Raptor Mach 2 joystick which
logical max is 239. The kernel interprets it as `-15` and thus ignores
the Hat Switch handling.

Link: https://gitlab.freedesktop.org/libevdev/udev-hid-bpf/-/issues/17
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
---
 include/linux/hid.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/linux/hid.h b/include/linux/hid.h
index b12cb1c8e682..8e06d89698e6 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -474,9 +474,9 @@ struct hid_usage {
 	__s8	  wheel_factor;		/* 120/resolution_multiplier */
 	__u16     code;			/* input driver code */
 	__u8      type;			/* input driver type */
-	__s8	  hat_min;		/* hat switch fun */
-	__s8	  hat_max;		/* ditto */
-	__s8	  hat_dir;		/* ditto */
+	__s16	  hat_min;		/* hat switch fun */
+	__s16	  hat_max;		/* ditto */
+	__s16	  hat_dir;		/* ditto */
 	__s16	  wheel_accumulated;	/* hi-res wheel */
 };
 

-- 
2.44.0

