root/arch/m68k/atari/joystick.c

/* */

DEFINITIONS

1. atari_joystick_interrupt
2. release_joystick
3. open_joystick
4. write_joystick
5. read_joystick
6. joystick_select
7. atari_joystick_init

   1 /*
   2  * Atari Joystick Driver for Linux
   3  * by Robert de Vries (robert@and.nl) 19Jul93
   4  *
   5  * 16 Nov 1994 Andreas Schwab
   6  * Support for three button mouse (shamelessly stolen from MiNT)
   7  * third button wired to one of the joystick directions on joystick 1
   8  */
   9 
  10 #include <linux/sched.h>
  11 #include <linux/errno.h>
  12 #include <linux/major.h>
  13 
  14 #include <asm/atarikb.h>
  15 #include <asm/atari_joystick.h>
  16 #include <asm/atari_mouse.h>
  17 #include <asm/segment.h>
  18 
  19 #define MAJOR_NR    JOYSTICK_MAJOR
  20 
  21 #define ANALOG_JOY(n)   (!(n & 0x80))
  22 #define DIGITAL_JOY(n)  (n & 0x80)
  23 #define DEVICE_NR(n)    (MINOR(n) & 0x7f)
  24 
  25 
  26 static struct joystick_status joystick[2];
  27 int atari_mouse_buttons; /* for three-button mouse */
  28 
  29 void atari_joystick_interrupt(char *buf)
     /*  */
  30 {
  31     int j;
  32 /*    ikbd_joystick_disable(); */
  33 
  34     j = buf[0] & 0x1;
  35     joystick[j].dir   = buf[1] & 0xF;
  36     joystick[j].fire  = (buf[1] & 0x80) >> 7;
  37     joystick[j].ready = 1;
  38     wake_up_interruptible(&joystick[j].wait);
  39 
  40     /* For three-button mouse emulation fake a mouse packet */
  41     if (atari_mouse_interrupt_hook &&
  42         j == 1 && (buf[1] & 1) != ((atari_mouse_buttons & 2) >> 1))
  43       {
  44         char faked_packet[3];
  45 
  46         atari_mouse_buttons = (atari_mouse_buttons & 5) | ((buf[1] & 1) << 1);
  47         faked_packet[0] = (atari_mouse_buttons & 1) | 
  48                           (atari_mouse_buttons & 4 ? 2 : 0);
  49         faked_packet[1] = 0;
  50         faked_packet[2] = 0;
  51         atari_mouse_interrupt_hook (faked_packet);
  52       }
  53 
  54 /*    ikbd_joystick_event_on(); */
  55 }
  56 
  57 static void release_joystick(struct inode *inode, struct file *file)
     /*  */
  58 {
  59     int minor = DEVICE_NR(inode->i_rdev);
  60 
  61     joystick[minor].active = 0;
  62     joystick[minor].ready = 0;
  63 
  64     if ((joystick[0].active == 0) && (joystick[1].active == 0))
  65         ikbd_joystick_disable();
  66 }
  67 
  68 static int open_joystick(struct inode *inode, struct file *file)
     /*  */
  69 {
  70     int minor = DEVICE_NR(inode->i_rdev);
  71 
  72     if (!DIGITAL_JOY(inode->i_rdev) || minor > 1)
  73         return -ENODEV;
  74     if (joystick[minor].active)
  75         return -EBUSY;
  76     joystick[minor].active = 1;
  77     joystick[minor].ready = 0;
  78     ikbd_joystick_event_on();
  79     return 0;
  80 }
  81 
  82 static int write_joystick(struct inode *inode, struct file *file,
     /*  */
  83                           const char *buffer, int count)
  84 {
  85     return -EINVAL;
  86 }
  87 
  88 static int read_joystick(struct inode *inode, struct file *file,
     /*  */
  89                          char *buffer, int count)
  90 {
  91     int minor = DEVICE_NR(inode->i_rdev);
  92     int i;
  93 
  94     if (count < 2)
  95         return -EINVAL;
  96     if (!joystick[minor].ready)
  97         return -EAGAIN;
  98     put_user(joystick[minor].fire, buffer++);
  99     put_user(joystick[minor].dir, buffer++);
 100     for (i = 0; i < count; i++)
 101         put_user(0, buffer++);
 102     joystick[minor].ready = 0;
 103 
 104     return i;
 105 }
 106 
 107 static int joystick_select(struct inode *inode, struct file *file, int sel_type, select_table *wait)
     /*  */
 108 {
 109     int minor = DEVICE_NR(inode->i_rdev);
 110 
 111     if (sel_type != SEL_IN)
 112         return 0;
 113     if (joystick[minor].ready)
 114         return 1;
 115     select_wait(&joystick[minor].wait, wait);
 116     return 0;
 117 }
 118 
 119 struct file_operations atari_joystick_fops = {
 120         NULL,           /* joystick_seek */
 121         read_joystick,
 122         write_joystick,
 123         NULL,           /* joystick_readdir */
 124         joystick_select,
 125         NULL,           /* joystick_ioctl */
 126         NULL,           /* joystick_mmap */
 127         open_joystick,
 128         release_joystick
 129 };
 130 
 131 int atari_joystick_init(void)
     /*  */
 132 {
 133     joystick[0].active = joystick[1].active = 0;
 134     joystick[0].ready = joystick[1].ready = 0;
 135     joystick[0].wait = joystick[1].wait = NULL;
 136 
 137     if (register_chrdev(MAJOR_NR, "joystick", &atari_joystick_fops))
 138         printk("unable to get major %d for joystick devices\n", MAJOR_NR);
 139 
 140     return 0;
 141 }

/* */