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
|
/*
* Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
*
* Under GPLv2
*/
#include <common.h>
#include <errno.h>
#include <init.h>
#include <clock.h>
#include <gpio_keys.h>
#include <poller.h>
#include <gpio.h>
static inline struct gpio_keys_platform_data *
poller_to_gk_pdata(struct poller_struct *poller)
{
return container_of(poller, struct gpio_keys_platform_data, poller);
}
static inline struct gpio_keys_platform_data *
cdev_to_gk_pdata(struct console_device *cdev)
{
return container_of(cdev, struct gpio_keys_platform_data, cdev);
}
static void gpio_key_poller(struct poller_struct *poller)
{
struct gpio_keys_platform_data *pdata = poller_to_gk_pdata(poller);
struct gpio_keys_button *gb;
int i, val;
for (i = 0; i < pdata->nbuttons; i++) {
gb = &pdata->buttons[i];
val = gpio_get_value(gb->gpio);
if (val != gb->previous_state && val != gb->active_low) {
kfifo_put(pdata->recv_fifo, (u_char*)&gb->code, sizeof(int));
debug("pressed gpio(%d) as %d\n", gb->gpio, gb->code);
}
gb->previous_state = val;
}
}
static int gpio_keys_tstc(struct console_device *cdev)
{
struct gpio_keys_platform_data *pdata = cdev_to_gk_pdata(cdev);
return (kfifo_len(pdata->recv_fifo) == 0) ? 0 : 1;
}
static int gpio_keys_getc(struct console_device *cdev)
{
int code = 0;
struct gpio_keys_platform_data *pdata = cdev_to_gk_pdata(cdev);
kfifo_get(pdata->recv_fifo, (u_char*)&code, sizeof(int));
return code;
}
static int __init gpio_keys_probe(struct device_d *dev)
{
int ret, i, gpio;
struct gpio_keys_platform_data *pdata;
struct console_device *cdev;
pdata = dev->platform_data;
if (!pdata) {
/* small (so we copy it) but critical! */
pr_err("missing platform_data\n");
return -ENODEV;
}
if (!pdata->fifo_size)
pdata->fifo_size = 50;
pdata->recv_fifo = kfifo_alloc(pdata->fifo_size);
for (i = 0; i < pdata->nbuttons; i++) {
gpio = pdata->buttons[i].gpio;
ret = gpio_request(gpio, "gpio_keys");
if (ret) {
pr_err("gpio_keys: (%d) can not be requested\n", gpio);
return ret;
}
gpio_direction_input(gpio);
}
pdata->poller.func = gpio_key_poller;
cdev = &pdata->cdev;
dev->type_data = cdev;
cdev->dev = dev;
cdev->f_caps = CONSOLE_STDIN;
cdev->tstc = gpio_keys_tstc;
cdev->getc = gpio_keys_getc;
console_register(&pdata->cdev);
return poller_register(&pdata->poller);
}
static struct driver_d gpio_keys_driver = {
.name = "gpio_keys",
.probe = gpio_keys_probe,
};
static int gpio_keys_init(void)
{
platform_driver_register(&gpio_keys_driver);
return 0;
}
device_initcall(gpio_keys_init);
|
