joystick.c

Ce bout de code marche bien pour le joystick 1 (à tester avec Joust) mais pas avec le joystick 0 si la souris est "branchée" (interferences). Si j'active le switch mouse_plugged alors ca marche.

/*
 * joystick.c - joystick thread (software part)
 *
 * Copyright (c) 2020-2024 Francois Galea <fgalea at free.fr>
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <stdint.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/joystick.h>
#include <stdio.h>

#include "config.h"

#define JOY_LED_FILE "/sys/class/leds/led0/brightness"

extern volatile uint32_t *parmreg;
extern volatile int thr_end;

struct axis_state {
    short x, y;
};

int read_event(int fd, struct js_event *event)
{
    ssize_t bytes;

    bytes = read(fd, event, sizeof(*event));

    if (bytes == sizeof(*event))
        return 0;

    /* Error, could not read full event. */
    return -1;
}

/**
 * Returns the number of axes on the controller or 0 if an error occurs.
 */
size_t get_axis_count(int fd)
{
    __u8 axes;

    if (ioctl(fd, JSIOCGAXES, &axes) == -1)
        return 0;

    return axes;
}

/**
 * Returns the number of buttons on the controller or 0 if an error occurs.
 */
size_t get_button_count(int fd)
{
    __u8 buttons;
    if (ioctl(fd, JSIOCGBUTTONS, &buttons) == -1)
        return 0;

    return buttons;
}

void joy_led_status(int fd,int st) {
  if (fd>=0) {
    char val = st?'1':'0';
    write(fd,&val,1);
  }
}

size_t get_axis_state(struct js_event *event, struct axis_state axes[3])
{
    size_t axis = event->number / 2;

    if (axis < 3)
    {
        if (event->number % 2 == 0)
            axes[axis].x = event->value;
        else
            axes[axis].y = event->value;
    }

    return axis;
}

void * thread_joystick(void * arg) {

  const char *device;
  int js;
  struct js_event event;
  struct axis_state axes[3] = {0};
  size_t axis;

  int joyfd = open(JOY_LED_FILE,O_WRONLY|O_SYNC);
  joy_led_status(joyfd, 1);

  printf("Opening icode\n");
  device = "/dev/input/js0";
  js = open(device, O_RDONLY);
  int joystick_nb = 5*1;

  if (js == -1) {
    perror("Could not open joystick");
  }

  int button_count = get_button_count(js);
  printf("buttons: %d\n", button_count);  

  /* This loop will exit if the controller is unplugged. */
  while (thr_end == 0) {
    read_event(js, &event);
    switch (event.type)
    {
        case JS_EVENT_BUTTON:
            printf("Button %u %s\n", event.number, event.value ? "pressed" : "released");
            parmreg[4+(122+joystick_nb)/32] = (parmreg[4+(122+joystick_nb)/32] & ~(1<<(122+joystick_nb)%32)) | (!event.value)<<((122+joystick_nb)%32);
            break;
        case JS_EVENT_AXIS:
            axis = get_axis_state(&event, axes);
            if (axis < 3) {
                printf("Axis %zu at (%6d, %6d)\n", axis, axes[axis].x, axes[axis].y);
                if(axes[axis].x < 0){
                    parmreg[4+(120+joystick_nb)/32] = (parmreg[4+(120+joystick_nb)/32] & ~(3<<(120+joystick_nb)%32)) | 2<<((120+joystick_nb)%32);
                }
                if(axes[axis].x > 0){
                    parmreg[4+(120+joystick_nb)/32] = (parmreg[4+(120+joystick_nb)/32] & ~(3<<(120+joystick_nb)%32)) | 1<<((120+joystick_nb)%32);
                }      
                if(axes[axis].y < 0){
                    parmreg[4+(118+joystick_nb)/32] = (parmreg[4+(118+joystick_nb)/32] & ~(3<<(118+joystick_nb)%32)) | 2<<((118+joystick_nb)%32);
                }
                if(axes[axis].y > 0){
                    parmreg[4+(118+joystick_nb)/32] = (parmreg[4+(118+joystick_nb)/32] & ~(3<<(118+joystick_nb)%32)) | 1<<((118+joystick_nb)%32);
                }   
                if(axes[axis].x == 0){
                    parmreg[4+(120+joystick_nb)/32] = (parmreg[4+(120+joystick_nb)/32] & ~(3<<(120+joystick_nb)%32)) | 3<<((120+joystick_nb)%32);
                }
                if(axes[axis].y == 0){
                    parmreg[4+(118+joystick_nb)/32] = (parmreg[4+(118+joystick_nb)/32] & ~(3<<(118+joystick_nb)%32)) | 3<<((118+joystick_nb)%32);
                }                
            }                       

            break;
        default:
            /* Ignore init events. */
            break;
    }
      
    fflush(stdout);
    
  }

  printf("Joystick unplugged!\n");
  close(js);

  return NULL;
}