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#include <linux/poll.h>
14#include <linux/init.h>
15#include <linux/devfs_fs_kernel.h>
16#include <linux/smp_lock.h>
17
18#include <asm/atarikb.h>
19#include <asm/atari_joystick.h>
20#include <asm/uaccess.h>
21
22#define MAJOR_NR    JOYSTICK_MAJOR
23
24#define	ANALOG_JOY(n)	(!(n & 0x80))
25#define	DIGITAL_JOY(n)	(n & 0x80)
26#define	DEVICE_NR(n)	(MINOR(n) & 0x7f)
27
28
29static struct joystick_status joystick[2];
30int atari_mouse_buttons; /* for three-button mouse */
31
32void atari_joystick_interrupt(char *buf)
33{
34    int j;
35/*    ikbd_joystick_disable(); */
36
37    j = buf[0] & 0x1;
38    joystick[j].dir   = buf[1] & 0xF;
39    joystick[j].fire  = (buf[1] & 0x80) >> 7;
40    joystick[j].ready = 1;
41    wake_up_interruptible(&joystick[j].wait);
42
43    /* For three-button mouse emulation fake a mouse packet */
44    if (atari_mouse_interrupt_hook &&
45	j == 1 && (buf[1] & 1) != ((atari_mouse_buttons & 2) >> 1))
46      {
47	char faked_packet[3];
48
49	atari_mouse_buttons = (atari_mouse_buttons & 5) | ((buf[1] & 1) << 1);
50	faked_packet[0] = (atari_mouse_buttons & 1) |
51			  (atari_mouse_buttons & 4 ? 2 : 0);
52	faked_packet[1] = 0;
53	faked_packet[2] = 0;
54	atari_mouse_interrupt_hook (faked_packet);
55      }
56
57/*    ikbd_joystick_event_on(); */
58}
59
60static int release_joystick(struct inode *inode, struct file *file)
61{
62    int minor = DEVICE_NR(inode->i_rdev);
63
64    lock_kernel();
65    joystick[minor].active = 0;
66    joystick[minor].ready = 0;
67
68    if ((joystick[0].active == 0) && (joystick[1].active == 0))
69	ikbd_joystick_disable();
70    unlock_kernel();
71    return 0;
72}
73
74static int open_joystick(struct inode *inode, struct file *file)
75{
76    int minor = DEVICE_NR(inode->i_rdev);
77
78    if (!DIGITAL_JOY(inode->i_rdev) || minor > 1)
79	return -ENODEV;
80    if (joystick[minor].active)
81	return -EBUSY;
82    joystick[minor].active = 1;
83    joystick[minor].ready = 0;
84    ikbd_joystick_event_on();
85    return 0;
86}
87
88static ssize_t write_joystick(struct file *file, const char *buffer,
89			      size_t count, loff_t *ppos)
90{
91    return -EINVAL;
92}
93
94static ssize_t read_joystick(struct file *file, char *buffer, size_t count,
95			     loff_t *ppos)
96{
97    struct inode *inode = file->f_dentry->d_inode;
98    int minor = DEVICE_NR(inode->i_rdev);
99
100    if (count < 2)
101	return -EINVAL;
102    if (!joystick[minor].ready)
103	return -EAGAIN;
104    joystick[minor].ready = 0;
105    if (put_user(joystick[minor].fire, buffer++) ||
106	put_user(joystick[minor].dir, buffer++))
107	return -EFAULT;
108    if (count > 2)
109	if (clear_user(buffer, count - 2))
110	    return -EFAULT;
111    return count;
112}
113
114static unsigned int joystick_poll(struct file *file, poll_table *wait)
115{
116    int minor = DEVICE_NR(file->f_dentry->d_inode->i_rdev);
117
118    poll_wait(file, &joystick[minor].wait, wait);
119    if (joystick[minor].ready)
120	return POLLIN | POLLRDNORM;
121    return 0;
122}
123
124struct file_operations atari_joystick_fops = {
125	read:		read_joystick,
126	write:		write_joystick,
127	poll:		joystick_poll,
128	open:		open_joystick,
129	release:	release_joystick,
130};
131
132int __init atari_joystick_init(void)
133{
134    joystick[0].active = joystick[1].active = 0;
135    joystick[0].ready = joystick[1].ready = 0;
136    init_waitqueue_head(&joystick[0].wait);
137    init_waitqueue_head(&joystick[1].wait);
138
139    if (devfs_register_chrdev(MAJOR_NR, "Joystick", &atari_joystick_fops))
140	printk("unable to get major %d for joystick devices\n", MAJOR_NR);
141    devfs_register_series (NULL, "joysticks/digital%u", 2, DEVFS_FL_DEFAULT,
142			   MAJOR_NR, 128, S_IFCHR | S_IRUSR | S_IWUSR,
143			   &atari_joystick_fops, NULL);
144
145    return 0;
146}
147