From 52ea899637c746984d657b508da6e3f2686adfca Mon Sep 17 00:00:00 2001 From: Peter Hutterer Date: Wed, 5 Dec 2018 10:42:21 +1000 Subject: Input: add `REL_WHEEL_HI_RES` and `REL_HWHEEL_HI_RES` This event code represents scroll reports from high-resolution wheels and is modelled after the approach Windows uses. The value 120 is one detent (wheel click) of movement. Mice with higher-resolution scrolling can send fractions of 120 which must be accumulated in userspace. Userspace can either wait for a full 120 to accumulate or scroll by fractions of one logical scroll movement as the events come in. 120 was picked as magic number because it has a high number of integer fractions that can be used by high-resolution wheels. For more information see https://docs.microsoft.com/en-us/previous-versions/windows/hardware/design/dn613912(v=vs.85) These new axes obsolete REL_WHEEL and REL_HWHEEL. The legacy axes are emulated by the kernel but the most accurate (and most granular) data is available through the new axes. Signed-off-by: Peter Hutterer Acked-by: Dmitry Torokhov Verified-by: Harry Cutts Signed-off-by: Benjamin Tissoires --- include/uapi/linux/input-event-codes.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/uapi') diff --git a/include/uapi/linux/input-event-codes.h b/include/uapi/linux/input-event-codes.h index 3eb5a4c3d60a..265ef2028660 100644 --- a/include/uapi/linux/input-event-codes.h +++ b/include/uapi/linux/input-event-codes.h @@ -716,6 +716,8 @@ * the situation described above. */ #define REL_RESERVED 0x0a +#define REL_WHEEL_HI_RES 0x0b +#define REL_HWHEEL_HI_RES 0x0c #define REL_MAX 0x0f #define REL_CNT (REL_MAX+1) -- cgit v1.2.3