so://phie

blob: 0ad045d264e90cd740c9d843ed2eb36396ffda10 (1613 bytes)[doc][blame][raw]

 1#include <stdio.h>
 2#include <fcntl.h>
 3#include <unistd.h>
 4#include <sys/mman.h>
 5
 6#include "libbcm2835.h"
 7
 8static volatile u32_t *reg = MAP_FAILED;
 9
10u32_t __bcm_bank(u32_t pin) {
11  return (pin >> 5);
12}
13
14int bcm_init(void) {
15  int fd = open("/dev/gpiomem", O_RDWR | O_SYNC);
16  if (fd < 0) {
17    fprintf(stderr, "Failed to open() /dev/gpiomem!\n");
18    return -1;
19  }
20  reg = (u32_t *) mmap(NULL, 0xB4, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
21  close(fd);
22  if (reg == MAP_FAILED) {
23    fprintf(stderr, "Bad, mmap() failed!\n");
24    return -1;
25  }
26  return 0;
27}
28
29void bcm_fsel(u32_t pin, bcm_fsel_e fsel) {
30  int idx = BCM_FSEL0 + (pin / 10);
31  int shift = 3 * (pin % 10);
32  reg[idx] = (reg[idx] & ~(7 << shift)) | (fsel << shift);
33}
34
35void bcm_set(u32_t pin) {
36  int idx = BCM_SET0 + __bcm_bank(pin);
37  reg[idx] = (1 << (pin & 0x1F));
38}
39
40void bcm_clr(u32_t pin) {
41  int idx = BCM_CLR0 + __bcm_bank(pin);
42  reg[idx] = (1 << (pin & 0x1F));
43}
44
45int bcm_lev(u32_t pin) {
46  int idx = BCM_LEV0 + __bcm_bank(pin);
47  return (reg[idx] & (1 << (pin & 0x1F))) != 0;
48}
49
50void bcm_pud(u32_t pin, bcm_pud_e pud) {
51  reg[BCM_PUD] = pud;
52  usleep(20);
53  reg[BCM_PUDCLK0 + __bcm_bank(pin)] = (1 << (pin & 0x1F));
54  usleep(20);
55  reg[BCM_PUD] = PUD_OFF;
56  reg[BCM_PUDCLK0 + __bcm_bank(pin)] = 0x00;
57}
58
59void bcm_write(u32_t pin, int level) {
60  level == HIGH
61    ? bcm_set(pin)
62    : bcm_clr(pin);
63}
64
65int bcm_read(u32_t pin) {
66  return bcm_lev(pin);
67}
68
69void bcm_pulse(u32_t pin, int level, u32_t sleep) {
70  level == HIGH
71    ? bcm_set(pin)
72    : bcm_clr(pin);
73  usleep(sleep);
74  level != HIGH
75    ? bcm_set(pin)
76    : bcm_clr(pin);
77}