Libgpiod on imx6ull

Technical Support
, ,
1

hi, I have my colibri-imx6ull running a Ångström/ OpenEmbedded based image that I cook with yocto, and I´m using the sysfs driver to control GPIO pins, that works fine, but is very slow, and I read that sysfs is deprecated, is posible to use libgpiod on my colibri-imx6ull/Ångström or libgpiod is only suported by torizon??

thanks

2

Libgpiod is supported not only by Torizon but by our “regular” BSP also since version 3.0b3. However 3.x BSP does not support Angstrom anymore.

3

sorry my ditro is not angstrom, my distro is “tdx-x11” and my bsp 5.0.

but I´m working in eclipse with the old sdk downloaded from toradex and this is 2017, and I don´t have the gpiod.h in the sysroot of my sdk :(.

I will try to make my own lib using linux/gpio.h and ioctl() functions.

4

gpio working with this code 20 times faster than sysfs

#include "my_gpio.h"
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <poll.h>
#include <string.h>
#include <sys/ioctl.h>

//manejadores para los 4 chips de gpio
int chip[4];

//llamar a esta funcion al inicia para abrir los manejadores de los chips gpio
void GPIO_init(void){
	chip[0] = open("/dev/gpiochip0", 0);
	chip[1] = open("/dev/gpiochip1", 0);
	chip[2] = open("/dev/gpiochip2", 0);
	chip[3] = open("/dev/gpiochip3", 0);
}

//esta funcion inicializa la direccion del gpio y me devuelve el manejador
struct gpiohandle_request * GPIO_get_handle(uint8_t nchip, uint8_t nport, bool direction, char * name){
	struct gpiohandle_request * req = malloc(sizeof(struct gpiohandle_request));

	req->lineoffsets[0] = nport;
	req->lines = 1;
	strcpy(req->consumer_label, name);

	if(direction == IN)		req->flags = GPIOHANDLE_REQUEST_INPUT;
	if(direction == OUT)	req->flags = GPIOHANDLE_REQUEST_OUTPUT;
	ioctl(chip[nchip], GPIO_GET_LINEHANDLE_IOCTL, req);

	return req;
}

void GPIO_set_value(struct gpiohandle_request * handle, bool value){
	struct gpiohandle_data data;

	data.values[0] = value;
	ioctl(handle->fd, GPIOHANDLE_SET_LINE_VALUES_IOCTL, &data);
}

bool GPIO_get_value(struct gpiohandle_request * handle){
	struct gpiohandle_data data;

	ioctl(handle->fd, GPIOHANDLE_GET_LINE_VALUES_IOCTL, &data);
	return (bool) data.values[0];
}
5

Thanks for your Input.

Best regards,
Jaski