imx6gpio.comp

component imx6gpio """Driver for iMX6 Phytec board""";

pin in bit pin-##-out[4] "Output pins";
pin out bit pin-##-in[4] "Input pins";

function read nofp "Reads each of the digital inputs and updates the HAL pins";
function write nofp "Writes the values of the output HAL pins to the digital IO";

variable u64 write_time;

option count_function no;

license "GPL";
author "Paul S";
;;

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <signal.h>
#include <sys/mman.h>
#define MAX_CHAN 5
//#define MAX_CHAN 4
//for x21 MAX_CHAN should be equal to 4 and for x51 MAX_CHAN is 5

int fd;

//addresses for x21 expantion on PBA-B-01 1364.1 revision of Phytec PhyFLEX development board
//using 4 gpios as input and 4 as output
//int inaddr[MAX_CHAN] = {0x20a8000, 0x209c000, 0x209c000, 0x20b4000};
//int outaddr[MAX_CHAN] = {0x20b4000, 0x20a8000, 0x20a0000, 0x20a0000};

//addresses for x54 expantion on PBA-B-01 1364.2 revision of Phytec PhyFLEX development board
//using 5 gpios as input and 5 as output, leaving gpio136 behind for now
int inaddr[MAX_CHAN] = {0x20ac000, 0x20a8000, 0x20a8000, 0x209c000, 0x209c000};
int outaddr[MAX_CHAN] = {0x20b4000, 0x20b4000, 0x20a8000, 0x20a0000, 0x20a0000};

FUNCTION(read){

    int i;
    //offsets for 1364.1 revision
    //int offset[MAX_CHAN] = {13, 5, 23, 24};
    //offsets for 1364.2 revision
    int offset[MAX_CHAN] = {7, 18, 19, 6, 9};
    volatile uint32_t *gpio;

    if ((fd = open ("/dev/mem", O_RDWR | O_SYNC) ) < 0) {
        printf("Unable to open /dev/mem: %s\n", strerror(errno));
        return -1;
    }

    for (i = 0; i < MAX_CHAN; i++){

        gpio = (uint32_t *)mmap(0, getpagesize(), PROT_READ|PROT_WRITE, MAP_SHARED, fd, inaddr[i]);

        if ((int32_t)gpio < 0){
            printf("Mmap failed: %s\n", strerror(errno));
            return -1;
        }

        //setting the registers to read mode
        *(gpio + 4) &= ~(1 << offset[i]);

        pin_in(i) = ((*gpio & (1 << offset[i])) >> offset[i]);

    }

    close(fd);
}

FUNCTION(write){

    int i;
    //offsets for 1364.1 revision
    //int offset[MAX_CHAN] = {19, 6, 9, 12};
    //offsets for 1364.2 revision
    int offset[MAX_CHAN] = {12, 13, 5, 23, 24};
    volatile uint32_t *gpio;

    if ((fd = open ("/dev/mem", O_RDWR | O_SYNC) ) < 0) {
        printf("Unable to open /dev/mem: %s\n", strerror(errno));
        return -1;
    }

    for (i = 0; i < MAX_CHAN; i++){

        gpio = (uint32_t *)mmap(0, getpagesize(), PROT_READ|PROT_WRITE, MAP_SHARED, fd, outaddr[i]);

        if ((int32_t)gpio < 0){
            printf("Mmap failed: %s\n", strerror(errno));
            return -1;
        }

        //setting the registers to write mode
        *(gpio + 4) |= (1 << offset[i]);

        //writing data

        if( pin_out(i) == 0)
            *gpio &= ~(1 << offset[i]);
        else
            *gpio |= (1 << offset[i]);

    }

    close(fd);
}