1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Generic helper functions for touchscreens and other two-dimensional
* pointing devices
*
* Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
*/
#include <linux/property.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/module.h>
static bool touchscreen_get_prop_u32(struct device *dev,
const char *property,
unsigned int default_value,
unsigned int *value)
{
u32 val;
int error;
error = device_property_read_u32(dev, property, &val);
if (error) {
*value = default_value;
return false;
}
*value = val;
return true;
}
static void touchscreen_set_params(struct input_dev *dev,
unsigned long axis,
int min, int max, int fuzz)
{
struct input_absinfo *absinfo;
if (!test_bit(axis, dev->absbit)) {
dev_warn(&dev->dev,
"Parameters are specified but the axis %lu is not set up\n",
axis);
return;
}
absinfo = &dev->absinfo[axis];
absinfo->minimum = min;
absinfo->maximum = max;
absinfo->fuzz = fuzz;
}
/**
* touchscreen_parse_properties - parse common touchscreen properties
* @input: input device that should be parsed
* @multitouch: specifies whether parsed properties should be applied to
* single-touch or multi-touch axes
* @prop: pointer to a struct touchscreen_properties into which to store
* axis swap and invert info for use with touchscreen_report_x_y();
* or %NULL
*
* This function parses common properties for touchscreens and sets up the
* input device accordingly. The function keeps previously set up default
* values if no value is specified.
*/
void touchscreen_parse_properties(struct input_dev *input, bool multitouch,
struct touchscreen_properties *prop)
{
struct device *dev = input->dev.parent;
struct input_absinfo *absinfo;
unsigned int axis, axis_x, axis_y;
unsigned int minimum, maximum, fuzz;
bool data_present;
input_alloc_absinfo(input);
if (!input->absinfo)
return;
axis_x = multitouch ? ABS_MT_POSITION_X : ABS_X;
axis_y = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-x",
input_abs_get_min(input, axis_x),
&minimum);
data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-x",
input_abs_get_max(input,
axis_x) + 1,
&maximum);
data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",
input_abs_get_fuzz(input, axis_x),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis_x, minimum, maximum - 1, fuzz);
data_present = touchscreen_get_prop_u32(dev, "touchscreen-min-y",
input_abs_get_min(input, axis_y),
&minimum);
data_present |= touchscreen_get_prop_u32(dev, "touchscreen-size-y",
input_abs_get_max(input,
axis_y) + 1,
&maximum);
data_present |= touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",
input_abs_get_fuzz(input, axis_y),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis_y, minimum, maximum - 1, fuzz);
axis = multitouch ? ABS_MT_PRESSURE : ABS_PRESSURE;
data_present = touchscreen_get_prop_u32(dev,
"touchscreen-max-pressure",
input_abs_get_max(input, axis),
&maximum);
data_present |= touchscreen_get_prop_u32(dev,
"touchscreen-fuzz-pressure",
input_abs_get_fuzz(input, axis),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis, 0, maximum, fuzz);
if (!prop)
return;
prop->max_x = input_abs_get_max(input, axis_x);
prop->max_y = input_abs_get_max(input, axis_y);
prop->invert_x =
device_property_read_bool(dev, "touchscreen-inverted-x");
if (prop->invert_x) {
absinfo = &input->absinfo[axis_x];
absinfo->maximum -= absinfo->minimum;
absinfo->minimum = 0;
}
prop->invert_y =
device_property_read_bool(dev, "touchscreen-inverted-y");
if (prop->invert_y) {
absinfo = &input->absinfo[axis_y];
absinfo->maximum -= absinfo->minimum;
absinfo->minimum = 0;
}
prop->swap_x_y =
device_property_read_bool(dev, "touchscreen-swapped-x-y");
if (prop->swap_x_y)
swap(input->absinfo[axis_x], input->absinfo[axis_y]);
}
EXPORT_SYMBOL(touchscreen_parse_properties);
static void
touchscreen_apply_prop_to_x_y(const struct touchscreen_properties *prop,
unsigned int *x, unsigned int *y)
{
if (prop->invert_x)
*x = prop->max_x - *x;
if (prop->invert_y)
*y = prop->max_y - *y;
if (prop->swap_x_y)
swap(*x, *y);
}
/**
* touchscreen_set_mt_pos - Set input_mt_pos coordinates
* @pos: input_mt_pos to set coordinates of
* @prop: pointer to a struct touchscreen_properties
* @x: X coordinate to store in pos
* @y: Y coordinate to store in pos
*
* Adjust the passed in x and y values applying any axis inversion and
* swapping requested in the passed in touchscreen_properties and store
* the result in a struct input_mt_pos.
*/
void touchscreen_set_mt_pos(struct input_mt_pos *pos,
const struct touchscreen_properties *prop,
unsigned int x, unsigned int y)
{
touchscreen_apply_prop_to_x_y(prop, &x, &y);
pos->x = x;
pos->y = y;
}
EXPORT_SYMBOL(touchscreen_set_mt_pos);
/**
* touchscreen_report_pos - Report touchscreen coordinates
* @input: input_device to report coordinates for
* @prop: pointer to a struct touchscreen_properties
* @x: X coordinate to report
* @y: Y coordinate to report
* @multitouch: Report coordinates on single-touch or multi-touch axes
*
* Adjust the passed in x and y values applying any axis inversion and
* swapping requested in the passed in touchscreen_properties and then
* report the resulting coordinates on the input_dev's x and y axis.
*/
void touchscreen_report_pos(struct input_dev *input,
const struct touchscreen_properties *prop,
unsigned int x, unsigned int y,
bool multitouch)
{
touchscreen_apply_prop_to_x_y(prop, &x, &y);
input_report_abs(input, multitouch ? ABS_MT_POSITION_X : ABS_X, x);
input_report_abs(input, multitouch ? ABS_MT_POSITION_Y : ABS_Y, y);
}
EXPORT_SYMBOL(touchscreen_report_pos);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Helper functions for touchscreens and other devices");
|
