| From dbf871c7a4ec1988b7963c1e49dd51e3276eedb7 Mon Sep 17 00:00:00 2001 |
| From: Peter Hutterer <peter.hutterer@who-t.net> |
| Date: Wed, 5 Dec 2018 10:42:21 +1000 |
| Subject: [PATCH] UPSTREAM: 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 <peter.hutterer@who-t.net> |
| Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> |
| (am from https://patchwork.kernel.org/patch/10712855/) |
| (also found at https://lkml.kernel.org/r/20181205004228.10714-2-peter.hutterer@who-t.net) |
| (cherry picked from commit 52ea899637c746984d657b508da6e3f2686adfca) |
| |
| BUG=chromium:888172 |
| TEST=None |
| |
| Change-Id: I205f0722ab9333834dbac156a0fbff244194e370 |
| Signed-off-by: Harry Cutts <hcutts@chromium.org> |
| Reviewed-on: https://chromium-review.googlesource.com/1465422 |
| Reviewed-by: Sean Paul <seanpaul@chromium.org> |
| Reviewed-by: Dmitry Torokhov <dtor@chromium.org> |
| --- |
| |
| diff --git a/include/uapi/linux/input-event-codes.h b/include/uapi/linux/input-event-codes.h |
| index 61769d4b7dbac7..3c755b6815c574 100644 |
| --- a/include/uapi/linux/input-event-codes.h |
| +++ b/include/uapi/linux/input-event-codes.h |
| @@ -706,6 +706,8 @@ |
| #define REL_DIAL 0x07 |
| #define REL_WHEEL 0x08 |
| #define REL_MISC 0x09 |
| +#define REL_WHEEL_HI_RES 0x0b |
| +#define REL_HWHEEL_HI_RES 0x0c |
| #define REL_MAX 0x0f |
| #define REL_CNT (REL_MAX+1) |
| |
| -- |
| 2.24.1.735.g03f4e72817-goog |
| |
