ardupilot/libraries/AP_HAL_Linux/GPIO_RPI.cpp

130 lines
3.3 KiB
C++

#include <AP_HAL/AP_HAL.h>
#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_ERLEBRAIN2 || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_BH || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_DARK || \
CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_PXFMINI
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include "GPIO.h"
#include "Util_RPI.h"
// Raspberry Pi GPIO memory
#define BCM2708_PERI_BASE 0x20000000
#define BCM2709_PERI_BASE 0x3F000000
#define GPIO_BASE(address) (address + 0x200000)
// GPIO setup. Always use INP_GPIO(x) before OUT_GPIO(x) or SET_GPIO_ALT(x,y)
#define GPIO_MODE_IN(g) *(_gpio+((g)/10)) &= ~(7<<(((g)%10)*3))
#define GPIO_MODE_OUT(g) *(_gpio+((g)/10)) |= (1<<(((g)%10)*3))
#define GPIO_MODE_ALT(g,a) *(_gpio+(((g)/10))) |= (((a)<=3?(a)+4:(a)==4?3:2)<<(((g)%10)*3))
#define GPIO_SET_HIGH *(_gpio+7) // sets bits which are 1
#define GPIO_SET_LOW *(_gpio+10) // clears bits which are 1
#define GPIO_GET(g) (*(_gpio+13)&(1<<g)) // 0 if LOW, (1<<g) if HIGH
#define GPIO_RPI_MAX_NUMBER_PINS 32
using namespace Linux;
static const AP_HAL::HAL &hal = AP_HAL::get_HAL();
GPIO_RPI::GPIO_RPI()
{
}
void GPIO_RPI::init()
{
int rpi_version = UtilRPI::from(hal.util)->get_rpi_version();
uint32_t gpio_address = rpi_version == 1 ? GPIO_BASE(BCM2708_PERI_BASE) : GPIO_BASE(BCM2709_PERI_BASE);
int mem_fd = open("/dev/mem", O_RDWR|O_SYNC|O_CLOEXEC);
if (mem_fd < 0) {
AP_HAL::panic("Can't open /dev/mem");
}
// mmap GPIO
void *gpio_map = mmap(
nullptr, // Any adddress in our space will do
BLOCK_SIZE, // Map length
PROT_READ|PROT_WRITE, // Enable reading & writting to mapped memory
MAP_SHARED, // Shared with other processes
mem_fd, // File to map
gpio_address // Offset to GPIO peripheral
);
close(mem_fd); // No need to keep mem_fd open after mmap
if (gpio_map == MAP_FAILED) {
AP_HAL::panic("Can't open /dev/mem");
}
_gpio = (volatile uint32_t *)gpio_map;
}
void GPIO_RPI::pinMode(uint8_t pin, uint8_t output)
{
if (output == HAL_GPIO_INPUT) {
GPIO_MODE_IN(pin);
} else {
GPIO_MODE_IN(pin);
GPIO_MODE_OUT(pin);
}
}
void GPIO_RPI::pinMode(uint8_t pin, uint8_t output, uint8_t alt)
{
if (output == HAL_GPIO_INPUT) {
GPIO_MODE_IN(pin);
} else if (output == HAL_GPIO_ALT) {
GPIO_MODE_IN(pin);
GPIO_MODE_ALT(pin, alt);
} else {
GPIO_MODE_IN(pin);
GPIO_MODE_OUT(pin);
}
}
uint8_t GPIO_RPI::read(uint8_t pin)
{
if (pin >= GPIO_RPI_MAX_NUMBER_PINS) {
return 0;
}
uint32_t value = GPIO_GET(pin);
return value ? 1: 0;
}
void GPIO_RPI::write(uint8_t pin, uint8_t value)
{
if (value == LOW) {
GPIO_SET_LOW = 1 << pin;
} else {
GPIO_SET_HIGH = 1 << pin;
}
}
void GPIO_RPI::toggle(uint8_t pin)
{
write(pin, !read(pin));
}
/* Alternative interface: */
AP_HAL::DigitalSource* GPIO_RPI::channel(uint16_t n)
{
return new DigitalSource(n);
}
bool GPIO_RPI::usb_connected(void)
{
return false;
}
#endif