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
|
/*
* Generic DT helper functions for touchscreen devices
*
* Copyright (c) 2014 Sebastian Reichel <sre@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
*/
#include <linux/property.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.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 max, int fuzz)
{
struct input_absinfo *absinfo;
if (!test_bit(axis, dev->absbit)) {
dev_warn(&dev->dev,
"DT specifies parameters but the axis %lu is not set up\n",
axis);
return;
}
absinfo = &dev->absinfo[axis];
absinfo->maximum = max;
absinfo->fuzz = fuzz;
}
/**
* touchscreen_parse_properties - parse common touchscreen DT properties
* @input: input device that should be parsed
* @multitouch: specifies whether parsed properties should be applied to
* single-touch or multi-touch axes
*
* This function parses common DT properties for touchscreens and setups the
* input device accordingly. The function keeps previously set up default
* values if no value is specified via DT.
*/
void touchscreen_parse_properties(struct input_dev *input, bool multitouch)
{
struct device *dev = input->dev.parent;
unsigned int axis;
unsigned int maximum, fuzz;
bool data_present;
input_alloc_absinfo(input);
if (!input->absinfo)
return;
axis = multitouch ? ABS_MT_POSITION_X : ABS_X;
data_present = touchscreen_get_prop_u32(dev, "touchscreen-size-x",
input_abs_get_max(input,
axis) + 1,
&maximum) |
touchscreen_get_prop_u32(dev, "touchscreen-fuzz-x",
input_abs_get_fuzz(input, axis),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis, maximum - 1, fuzz);
axis = multitouch ? ABS_MT_POSITION_Y : ABS_Y;
data_present = touchscreen_get_prop_u32(dev, "touchscreen-size-y",
input_abs_get_max(input,
axis) + 1,
&maximum) |
touchscreen_get_prop_u32(dev, "touchscreen-fuzz-y",
input_abs_get_fuzz(input, axis),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis, 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) |
touchscreen_get_prop_u32(dev,
"touchscreen-fuzz-pressure",
input_abs_get_fuzz(input, axis),
&fuzz);
if (data_present)
touchscreen_set_params(input, axis, maximum, fuzz);
}
EXPORT_SYMBOL(touchscreen_parse_properties);
|
