cmd_gpio.c
1.85 KB
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
/*
* Control GPIO pins on the fly
*
* Copyright (c) 2008-2011 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <common.h>
#include <command.h>
#include <asm/gpio.h>
#ifndef name_to_gpio
#define name_to_gpio(name) simple_strtoul(name, NULL, 10)
#endif
enum gpio_cmd {
GPIO_INPUT,
GPIO_SET,
GPIO_CLEAR,
GPIO_TOGGLE,
};
static int do_gpio(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
int gpio;
enum gpio_cmd sub_cmd;
ulong value;
const char *str_cmd, *str_gpio;
#ifdef gpio_status
if (argc == 2 && !strcmp(argv[1], "status")) {
gpio_status();
return 0;
}
#endif
if (argc != 3)
show_usage:
return CMD_RET_USAGE;
str_cmd = argv[1];
str_gpio = argv[2];
/* parse the behavior */
switch (*str_cmd) {
case 'i': sub_cmd = GPIO_INPUT; break;
case 's': sub_cmd = GPIO_SET; break;
case 'c': sub_cmd = GPIO_CLEAR; break;
case 't': sub_cmd = GPIO_TOGGLE; break;
default: goto show_usage;
}
/* turn the gpio name into a gpio number */
gpio = name_to_gpio(str_gpio);
if (gpio < 0)
goto show_usage;
/* grab the pin before we tweak it */
if (gpio_request(gpio, "cmd_gpio")) {
printf("gpio: requesting pin %u failed\n", gpio);
return -1;
}
/* finally, let's do it: set direction and exec command */
if (sub_cmd == GPIO_INPUT) {
gpio_direction_input(gpio);
value = gpio_get_value(gpio);
} else {
switch (sub_cmd) {
case GPIO_SET: value = 1; break;
case GPIO_CLEAR: value = 0; break;
case GPIO_TOGGLE: value = !gpio_get_value(gpio); break;
default: goto show_usage;
}
gpio_direction_output(gpio, value);
}
printf("gpio: pin %s (gpio %i) value is %lu\n",
str_gpio, gpio, value);
gpio_free(gpio);
return value;
}
U_BOOT_CMD(gpio, 3, 0, do_gpio,
"input/set/clear/toggle gpio pins",
"<input|set|clear|toggle> <pin>\n"
" - input/set/clear/toggle the specified pin");