libinput/src/evdev-tablet-pad.h
Peter Hutterer 9ae15c6a45 pad: be more robust to kernel bugs of multiple EV_ABS
This is a workaround for a kernel bug with the Wacom Mobile Studio Pro
13: this device sends erroneous ABS_WHEEL events when pressing
buttons:

  - evdev:
    - [  0,      0,   1, 256,       1] # EV_KEY / BTN_0                     1
    - [  0,      0,   3,   8,      17] # EV_ABS / ABS_WHEEL                17 (+17)
    - [  0,      0,   3,   8,       0] # EV_ABS / ABS_WHEEL                 0 (-17)
    - [  0,      0,   3,  40,      15] # EV_ABS / ABS_MISC                 15 (+15)
    - [  0,      0,   0,   0,       0] # ------------ SYN_REPORT (0) ---------- +0ms

ABS_WHEEL to 17 then to 0 in the same frame. We should (and do) treat this
as a zero event and drop the 17 to the floor. Alas, we then generate a
ring event for the zero value despite our current value being zero
anyway. This again causes confusing behavior.

This is simple enough to work around, at least until the kernel is fixed
but also to prevent this happening in the future: warn if we get
multiple events and if so and the later event is zero, undo the axis
change state.

Closes: #1081
Part-of: <https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/1136>
2025-02-12 03:58:23 +00:00

126 lines
3.4 KiB
C

/*
* Copyright © 2015 Red Hat, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#ifndef EVDEV_TABLET_PAD_H
#define EVDEV_TABLET_PAD_H
#include "evdev.h"
#if !HAVE_LIBWACOM
typedef void * WacomDevice;
#endif
#define LIBINPUT_BUTTONSET_AXIS_NONE 0
enum pad_status {
PAD_NONE = 0,
PAD_AXES_UPDATED = bit(0),
PAD_BUTTONS_PRESSED = bit(1),
PAD_BUTTONS_RELEASED = bit(2),
};
enum pad_axes {
PAD_AXIS_NONE = 0,
PAD_AXIS_RING1 = bit(0),
PAD_AXIS_RING2 = bit(1),
PAD_AXIS_STRIP1 = bit(2),
PAD_AXIS_STRIP2 = bit(3),
PAD_AXIS_DIAL1 = bit(4),
PAD_AXIS_DIAL2 = bit(5),
};
struct button_state {
unsigned char bits[NCHARS(KEY_CNT)];
};
typedef struct {
uint32_t value;
} key_or_button_map_t;
#define map_init(x_) ((x_).value = (uint32_t)-1)
#define map_is_unmapped(x_) ((x_).value == (uint32_t)-1)
#define map_is_button(x_) (((x_).value & 0xFF000000) == 0)
#define map_is_key(x_) (((x_).value & 0xFF000000) != 0)
#define map_set_button_map(field_, value_) ((field_).value = value_)
#define map_set_key_map(field_, value_) ((field_).value = value_ | 0xFF000000)
#define map_value(x_) ((x_).value & 0x00FFFFFF)
struct pad_dispatch {
struct evdev_dispatch base;
struct evdev_device *device;
unsigned char status;
uint32_t changed_axes;
struct button_state button_state;
struct button_state prev_button_state;
key_or_button_map_t button_map[KEY_CNT];
unsigned int nbuttons;
bool have_abs_misc_terminator;
struct {
bool has_hires_dial;
double dial1;
double dial2;
} dials;
struct {
struct libinput_device_config_send_events config;
enum libinput_config_send_events_mode current_mode;
} sendevents;
struct {
struct list mode_group_list;
} modes;
struct ratelimit duplicate_abs_limit;
};
static inline struct pad_dispatch*
pad_dispatch(struct evdev_dispatch *dispatch)
{
evdev_verify_dispatch_type(dispatch, DISPATCH_TABLET_PAD);
return container_of(dispatch, struct pad_dispatch, base);
}
static inline struct libinput *
pad_libinput_context(const struct pad_dispatch *pad)
{
return evdev_libinput_context(pad->device);
}
int
pad_init_leds(struct pad_dispatch *pad,
struct evdev_device *device,
WacomDevice *wacom);
void
pad_destroy_leds(struct pad_dispatch *pad);
void
pad_button_update_mode(struct libinput_tablet_pad_mode_group *g,
unsigned int button_index,
enum libinput_button_state state);
#endif