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
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Microchip AR1020 and AR1021 driver for I2C
*
* Author: Christian Gmeiner <christian.gmeiner@gmail.com>
*/
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/input.h>
#include <linux/of.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#define AR1021_TOUCH_PKG_SIZE 5
#define AR1021_MAX_X 4095
#define AR1021_MAX_Y 4095
#define AR1021_CMD 0x55
#define AR1021_CMD_ENABLE_TOUCH 0x12
struct ar1021_i2c {
struct i2c_client *client;
struct input_dev *input;
u8 data[AR1021_TOUCH_PKG_SIZE];
};
static irqreturn_t ar1021_i2c_irq(int irq, void *dev_id)
{
struct ar1021_i2c *ar1021 = dev_id;
struct input_dev *input = ar1021->input;
u8 *data = ar1021->data;
unsigned int x, y, button;
int retval;
retval = i2c_master_recv(ar1021->client,
ar1021->data, sizeof(ar1021->data));
if (retval != sizeof(ar1021->data))
goto out;
/* sync bit set ? */
if (!(data[0] & BIT(7)))
goto out;
button = data[0] & BIT(0);
x = ((data[2] & 0x1f) << 7) | (data[1] & 0x7f);
y = ((data[4] & 0x1f) << 7) | (data[3] & 0x7f);
input_report_abs(input, ABS_X, x);
input_report_abs(input, ABS_Y, y);
input_report_key(input, BTN_TOUCH, button);
input_sync(input);
out:
return IRQ_HANDLED;
}
static int ar1021_i2c_open(struct input_dev *dev)
{
static const u8 cmd_enable_touch[] = {
AR1021_CMD,
0x01, /* number of bytes after this */
AR1021_CMD_ENABLE_TOUCH
};
struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
struct i2c_client *client = ar1021->client;
int error;
error = i2c_master_send(ar1021->client, cmd_enable_touch,
sizeof(cmd_enable_touch));
if (error < 0)
return error;
enable_irq(client->irq);
return 0;
}
static void ar1021_i2c_close(struct input_dev *dev)
{
struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
struct i2c_client *client = ar1021->client;
disable_irq(client->irq);
}
static int ar1021_i2c_probe(struct i2c_client *client)
{
struct ar1021_i2c *ar1021;
struct input_dev *input;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "i2c_check_functionality error\n");
return -ENXIO;
}
ar1021 = devm_kzalloc(&client->dev, sizeof(*ar1021), GFP_KERNEL);
if (!ar1021)
return -ENOMEM;
input = devm_input_allocate_device(&client->dev);
if (!input)
return -ENOMEM;
ar1021->client = client;
ar1021->input = input;
input->name = "ar1021 I2C Touchscreen";
input->id.bustype = BUS_I2C;
input->dev.parent = &client->dev;
input->open = ar1021_i2c_open;
input->close = ar1021_i2c_close;
__set_bit(INPUT_PROP_DIRECT, input->propbit);
input_set_capability(input, EV_KEY, BTN_TOUCH);
input_set_abs_params(input, ABS_X, 0, AR1021_MAX_X, 0, 0);
input_set_abs_params(input, ABS_Y, 0, AR1021_MAX_Y, 0, 0);
input_set_drvdata(input, ar1021);
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, ar1021_i2c_irq,
IRQF_ONESHOT | IRQF_NO_AUTOEN,
"ar1021_i2c", ar1021);
if (error) {
dev_err(&client->dev,
"Failed to enable IRQ, error: %d\n", error);
return error;
}
error = input_register_device(ar1021->input);
if (error) {
dev_err(&client->dev,
"Failed to register input device, error: %d\n", error);
return error;
}
return 0;
}
static int __maybe_unused ar1021_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
disable_irq(client->irq);
return 0;
}
static int __maybe_unused ar1021_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
enable_irq(client->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(ar1021_i2c_pm, ar1021_i2c_suspend, ar1021_i2c_resume);
static const struct i2c_device_id ar1021_i2c_id[] = {
{ "ar1021", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, ar1021_i2c_id);
static const struct of_device_id ar1021_i2c_of_match[] = {
{ .compatible = "microchip,ar1021-i2c", },
{ }
};
MODULE_DEVICE_TABLE(of, ar1021_i2c_of_match);
static struct i2c_driver ar1021_i2c_driver = {
.driver = {
.name = "ar1021_i2c",
.pm = &ar1021_i2c_pm,
.of_match_table = ar1021_i2c_of_match,
},
.probe_new = ar1021_i2c_probe,
.id_table = ar1021_i2c_id,
};
module_i2c_driver(ar1021_i2c_driver);
MODULE_AUTHOR("Christian Gmeiner <christian.gmeiner@gmail.com>");
MODULE_DESCRIPTION("Microchip AR1020 and AR1021 I2C Driver");
MODULE_LICENSE("GPL");
|
