openpilot/selfdrive/common/gpio.cc

32 lines
939 B
C++

#include "selfdrive/common/gpio.h"
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include "selfdrive/common/util.h"
// We assume that all pins have already been exported on boot,
// and that we have permission to write to them.
int gpio_init(int pin_nr, bool output){
char pin_dir_path[50];
int pin_dir_path_len = snprintf(pin_dir_path, sizeof(pin_dir_path),
"/sys/class/gpio/gpio%d/direction", pin_nr);
if(pin_dir_path_len <= 0){
return -1;
}
const char *value = output ? "out" : "in";
return util::write_file(pin_dir_path, (void*)value, strlen(value));
}
int gpio_set(int pin_nr, bool high){
char pin_val_path[50];
int pin_val_path_len = snprintf(pin_val_path, sizeof(pin_val_path),
"/sys/class/gpio/gpio%d/value", pin_nr);
if(pin_val_path_len <= 0){
return -1;
}
return util::write_file(pin_val_path, (void*)(high ? "1" : "0"), 1);
}