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
208
209
210
|
/*
* Driver for tilt switches connected via GPIO lines
* not capable of generating interrupts
*
* Copyright (C) 2011 Heiko Stuebner <heiko@sntech.de>
*
* based on: drivers/input/keyboard/gpio_keys_polled.c
*
* Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
* Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
*
* 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/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input.h>
#include <linux/input-polldev.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/input/gpio_tilt.h>
#define DRV_NAME "gpio-tilt-polled"
struct gpio_tilt_polled_dev {
struct input_polled_dev *poll_dev;
struct device *dev;
const struct gpio_tilt_platform_data *pdata;
int last_state;
int threshold;
int count;
};
static void gpio_tilt_polled_poll(struct input_polled_dev *dev)
{
struct gpio_tilt_polled_dev *tdev = dev->private;
const struct gpio_tilt_platform_data *pdata = tdev->pdata;
struct input_dev *input = dev->input;
struct gpio_tilt_state *tilt_state = NULL;
int state, i;
if (tdev->count < tdev->threshold) {
tdev->count++;
} else {
state = 0;
for (i = 0; i < pdata->nr_gpios; i++)
state |= (!!gpio_get_value(pdata->gpios[i].gpio) << i);
if (state != tdev->last_state) {
for (i = 0; i < pdata->nr_states; i++)
if (pdata->states[i].gpios == state)
tilt_state = &pdata->states[i];
if (tilt_state) {
for (i = 0; i < pdata->nr_axes; i++)
input_report_abs(input,
pdata->axes[i].axis,
tilt_state->axes[i]);
input_sync(input);
}
tdev->count = 0;
tdev->last_state = state;
}
}
}
static void gpio_tilt_polled_open(struct input_polled_dev *dev)
{
struct gpio_tilt_polled_dev *tdev = dev->private;
const struct gpio_tilt_platform_data *pdata = tdev->pdata;
if (pdata->enable)
pdata->enable(tdev->dev);
/* report initial state of the axes */
tdev->last_state = -1;
tdev->count = tdev->threshold;
gpio_tilt_polled_poll(tdev->poll_dev);
}
static void gpio_tilt_polled_close(struct input_polled_dev *dev)
{
struct gpio_tilt_polled_dev *tdev = dev->private;
const struct gpio_tilt_platform_data *pdata = tdev->pdata;
if (pdata->disable)
pdata->disable(tdev->dev);
}
static int gpio_tilt_polled_probe(struct platform_device *pdev)
{
const struct gpio_tilt_platform_data *pdata =
dev_get_platdata(&pdev->dev);
struct device *dev = &pdev->dev;
struct gpio_tilt_polled_dev *tdev;
struct input_polled_dev *poll_dev;
struct input_dev *input;
int error, i;
if (!pdata || !pdata->poll_interval)
return -EINVAL;
tdev = kzalloc(sizeof(struct gpio_tilt_polled_dev), GFP_KERNEL);
if (!tdev) {
dev_err(dev, "no memory for private data\n");
return -ENOMEM;
}
error = gpio_request_array(pdata->gpios, pdata->nr_gpios);
if (error) {
dev_err(dev,
"Could not request tilt GPIOs: %d\n", error);
goto err_free_tdev;
}
poll_dev = input_allocate_polled_device();
if (!poll_dev) {
dev_err(dev, "no memory for polled device\n");
error = -ENOMEM;
goto err_free_gpios;
}
poll_dev->private = tdev;
poll_dev->poll = gpio_tilt_polled_poll;
poll_dev->poll_interval = pdata->poll_interval;
poll_dev->open = gpio_tilt_polled_open;
poll_dev->close = gpio_tilt_polled_close;
input = poll_dev->input;
input->name = pdev->name;
input->phys = DRV_NAME"/input0";
input->dev.parent = dev;
input->id.bustype = BUS_HOST;
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
__set_bit(EV_ABS, input->evbit);
for (i = 0; i < pdata->nr_axes; i++)
input_set_abs_params(input, pdata->axes[i].axis,
pdata->axes[i].min, pdata->axes[i].max,
pdata->axes[i].fuzz, pdata->axes[i].flat);
tdev->threshold = DIV_ROUND_UP(pdata->debounce_interval,
pdata->poll_interval);
tdev->poll_dev = poll_dev;
tdev->dev = dev;
tdev->pdata = pdata;
error = input_register_polled_device(poll_dev);
if (error) {
dev_err(dev, "unable to register polled device, err=%d\n",
error);
goto err_free_polldev;
}
platform_set_drvdata(pdev, tdev);
return 0;
err_free_polldev:
input_free_polled_device(poll_dev);
err_free_gpios:
gpio_free_array(pdata->gpios, pdata->nr_gpios);
err_free_tdev:
kfree(tdev);
return error;
}
static int gpio_tilt_polled_remove(struct platform_device *pdev)
{
struct gpio_tilt_polled_dev *tdev = platform_get_drvdata(pdev);
const struct gpio_tilt_platform_data *pdata = tdev->pdata;
input_unregister_polled_device(tdev->poll_dev);
input_free_polled_device(tdev->poll_dev);
gpio_free_array(pdata->gpios, pdata->nr_gpios);
kfree(tdev);
return 0;
}
static struct platform_driver gpio_tilt_polled_driver = {
.probe = gpio_tilt_polled_probe,
.remove = gpio_tilt_polled_remove,
.driver = {
.name = DRV_NAME,
},
};
module_platform_driver(gpio_tilt_polled_driver);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
MODULE_DESCRIPTION("Polled GPIO tilt driver");
MODULE_ALIAS("platform:" DRV_NAME);
|
