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
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
|
/*
* Driver for keys on GPIO lines capable of generating interrupts.
*
* Copyright 2005 Phil Blundell
*
* 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/module.h>
#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/gpio_keys.h>
#include <asm/gpio.h>
struct gpio_button_data {
struct gpio_keys_button *button;
struct input_dev *input;
struct timer_list timer;
};
struct gpio_keys_drvdata {
struct input_dev *input;
struct gpio_button_data data[0];
};
static void gpio_keys_report_event(struct gpio_keys_button *button,
struct input_dev *input)
{
unsigned int type = button->type ?: EV_KEY;
int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low;
input_event(input, type, button->code, !!state);
input_sync(input);
}
static void gpio_check_button(unsigned long _data)
{
struct gpio_button_data *data = (struct gpio_button_data *)_data;
gpio_keys_report_event(data->button, data->input);
}
static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
{
struct platform_device *pdev = dev_id;
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
int i;
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
if (irq == gpio_to_irq(button->gpio)) {
struct gpio_button_data *bdata = &ddata->data[i];
if (button->debounce_interval)
mod_timer(&bdata->timer,
jiffies +
msecs_to_jiffies(button->debounce_interval));
else
gpio_keys_report_event(button, bdata->input);
return IRQ_HANDLED;
}
}
return IRQ_NONE;
}
static int __devinit gpio_keys_probe(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct gpio_keys_drvdata *ddata;
struct input_dev *input;
int i, error;
int wakeup = 0;
ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
pdata->nbuttons * sizeof(struct gpio_button_data),
GFP_KERNEL);
input = input_allocate_device();
if (!ddata || !input) {
error = -ENOMEM;
goto fail1;
}
platform_set_drvdata(pdev, ddata);
input->name = pdev->name;
input->phys = "gpio-keys/input0";
input->dev.parent = &pdev->dev;
input->id.bustype = BUS_HOST;
input->id.vendor = 0x0001;
input->id.product = 0x0001;
input->id.version = 0x0100;
ddata->input = input;
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
struct gpio_button_data *bdata = &ddata->data[i];
int irq;
unsigned int type = button->type ?: EV_KEY;
bdata->input = input;
bdata->button = button;
setup_timer(&bdata->timer,
gpio_check_button, (unsigned long)bdata);
error = gpio_request(button->gpio, button->desc ?: "gpio_keys");
if (error < 0) {
pr_err("gpio-keys: failed to request GPIO %d,"
" error %d\n", button->gpio, error);
goto fail2;
}
error = gpio_direction_input(button->gpio);
if (error < 0) {
pr_err("gpio-keys: failed to configure input"
" direction for GPIO %d, error %d\n",
button->gpio, error);
gpio_free(button->gpio);
goto fail2;
}
irq = gpio_to_irq(button->gpio);
if (irq < 0) {
error = irq;
pr_err("gpio-keys: Unable to get irq number"
" for GPIO %d, error %d\n",
button->gpio, error);
gpio_free(button->gpio);
goto fail2;
}
error = request_irq(irq, gpio_keys_isr,
IRQF_SAMPLE_RANDOM | IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING,
button->desc ? button->desc : "gpio_keys",
pdev);
if (error) {
pr_err("gpio-keys: Unable to claim irq %d; error %d\n",
irq, error);
gpio_free(button->gpio);
goto fail2;
}
if (button->wakeup)
wakeup = 1;
input_set_capability(input, type, button->code);
}
error = input_register_device(input);
if (error) {
pr_err("gpio-keys: Unable to register input device, "
"error: %d\n", error);
goto fail2;
}
device_init_wakeup(&pdev->dev, wakeup);
return 0;
fail2:
while (--i >= 0) {
free_irq(gpio_to_irq(pdata->buttons[i].gpio), pdev);
if (pdata->buttons[i].debounce_interval)
del_timer_sync(&ddata->data[i].timer);
gpio_free(pdata->buttons[i].gpio);
}
platform_set_drvdata(pdev, NULL);
fail1:
input_free_device(input);
kfree(ddata);
return error;
}
static int __devexit gpio_keys_remove(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
struct input_dev *input = ddata->input;
int i;
device_init_wakeup(&pdev->dev, 0);
for (i = 0; i < pdata->nbuttons; i++) {
int irq = gpio_to_irq(pdata->buttons[i].gpio);
free_irq(irq, pdev);
if (pdata->buttons[i].debounce_interval)
del_timer_sync(&ddata->data[i].timer);
gpio_free(pdata->buttons[i].gpio);
}
input_unregister_device(input);
return 0;
}
#ifdef CONFIG_PM
static int gpio_keys_suspend(struct platform_device *pdev, pm_message_t state)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
int i;
if (device_may_wakeup(&pdev->dev)) {
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
if (button->wakeup) {
int irq = gpio_to_irq(button->gpio);
enable_irq_wake(irq);
}
}
}
return 0;
}
static int gpio_keys_resume(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
int i;
if (device_may_wakeup(&pdev->dev)) {
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
if (button->wakeup) {
int irq = gpio_to_irq(button->gpio);
disable_irq_wake(irq);
}
}
}
return 0;
}
#else
#define gpio_keys_suspend NULL
#define gpio_keys_resume NULL
#endif
struct platform_driver gpio_keys_device_driver = {
.probe = gpio_keys_probe,
.remove = __devexit_p(gpio_keys_remove),
.suspend = gpio_keys_suspend,
.resume = gpio_keys_resume,
.driver = {
.name = "gpio-keys",
.owner = THIS_MODULE,
}
};
static int __init gpio_keys_init(void)
{
return platform_driver_register(&gpio_keys_device_driver);
}
static void __exit gpio_keys_exit(void)
{
platform_driver_unregister(&gpio_keys_device_driver);
}
module_init(gpio_keys_init);
module_exit(gpio_keys_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");
MODULE_ALIAS("platform:gpio-keys");
|
