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15#include <linux/module.h>
16#include <linux/init.h>
17#include <linux/kdev_t.h>
18#include <linux/cdev.h>
19#include <linux/fs.h>
20#include <asm/io.h>
21#include <asm/uaccess.h>
22#include <mach-landisk/mach/gio.h>
23#include <mach-landisk/mach/iodata_landisk.h>
24
25#define DEVCOUNT 4
26#define GIO_MINOR 2
27
28static dev_t dev;
29static struct cdev *cdev_p;
30static int openCnt;
31
32static int gio_open(struct inode *inode, struct file *filp)
33{
34 int minor;
35 int ret = -ENOENT;
36
37 preempt_disable();
38 minor = MINOR(inode->i_rdev);
39 if (minor < DEVCOUNT) {
40 if (openCnt > 0) {
41 ret = -EALREADY;
42 } else {
43 openCnt++;
44 ret = 0;
45 }
46 }
47 preempt_enable();
48 return ret;
49}
50
51static int gio_close(struct inode *inode, struct file *filp)
52{
53 int minor;
54
55 minor = MINOR(inode->i_rdev);
56 if (minor < DEVCOUNT) {
57 openCnt--;
58 }
59 return 0;
60}
61
62static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
63{
64 unsigned int data;
65 static unsigned int addr = 0;
66
67 if (cmd & 0x01) {
68 if (copy_from_user(&data, (int *)arg, sizeof(int))) {
69 return -EFAULT;
70 }
71 }
72
73 switch (cmd) {
74 case GIODRV_IOCSGIOSETADDR:
75 addr = data;
76 break;
77
78 case GIODRV_IOCSGIODATA1:
79 __raw_writeb((unsigned char)(0x0ff & data), addr);
80 break;
81
82 case GIODRV_IOCSGIODATA2:
83 if (addr & 0x01) {
84 return -EFAULT;
85 }
86 __raw_writew((unsigned short int)(0x0ffff & data), addr);
87 break;
88
89 case GIODRV_IOCSGIODATA4:
90 if (addr & 0x03) {
91 return -EFAULT;
92 }
93 __raw_writel(data, addr);
94 break;
95
96 case GIODRV_IOCGGIODATA1:
97 data = __raw_readb(addr);
98 break;
99
100 case GIODRV_IOCGGIODATA2:
101 if (addr & 0x01) {
102 return -EFAULT;
103 }
104 data = __raw_readw(addr);
105 break;
106
107 case GIODRV_IOCGGIODATA4:
108 if (addr & 0x03) {
109 return -EFAULT;
110 }
111 data = __raw_readl(addr);
112 break;
113 default:
114 return -EFAULT;
115 break;
116 }
117
118 if ((cmd & 0x01) == 0) {
119 if (copy_to_user((int *)arg, &data, sizeof(int))) {
120 return -EFAULT;
121 }
122 }
123 return 0;
124}
125
126static const struct file_operations gio_fops = {
127 .owner = THIS_MODULE,
128 .open = gio_open,
129 .release = gio_close,
130 .unlocked_ioctl = gio_ioctl,
131 .llseek = noop_llseek,
132};
133
134static int __init gio_init(void)
135{
136 int error;
137
138 printk(KERN_INFO "gio: driver initialized\n");
139
140 openCnt = 0;
141
142 if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
143 printk(KERN_ERR
144 "gio: Couldn't alloc_chrdev_region, error=%d\n",
145 error);
146 return 1;
147 }
148
149 cdev_p = cdev_alloc();
150 cdev_p->ops = &gio_fops;
151 error = cdev_add(cdev_p, dev, DEVCOUNT);
152 if (error) {
153 printk(KERN_ERR
154 "gio: Couldn't cdev_add, error=%d\n", error);
155 return 1;
156 }
157
158 return 0;
159}
160
161static void __exit gio_exit(void)
162{
163 cdev_del(cdev_p);
164 unregister_chrdev_region(dev, DEVCOUNT);
165}
166
167module_init(gio_init);
168module_exit(gio_exit);
169
170MODULE_LICENSE("GPL");
171