1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * arch/sh/boards/landisk/gio.c - driver for landisk
4 *
5 * This driver will also support the I-O DATA Device, Inc. LANDISK Board.
6 * LANDISK and USL-5P Button, LED and GIO driver drive function.
7 *
8 * Copylight (C) 2006 kogiidena
9 * Copylight (C) 2002 Atom Create Engineering Co., Ltd. *
10 */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/kdev_t.h>
14 #include <linux/cdev.h>
15 #include <linux/fs.h>
16 #include <asm/io.h>
17 #include <linux/uaccess.h>
18 #include <mach-landisk/mach/gio.h>
19 #include <mach-landisk/mach/iodata_landisk.h>
20
21 #define DEVCOUNT 4
22 #define GIO_MINOR 2 /* GIO minor no. */
23
24 static dev_t dev;
25 static struct cdev *cdev_p;
26 static int openCnt;
27
gio_open(struct inode * inode,struct file * filp)28 static int gio_open(struct inode *inode, struct file *filp)
29 {
30 int minor;
31 int ret = -ENOENT;
32
33 preempt_disable();
34 minor = MINOR(inode->i_rdev);
35 if (minor < DEVCOUNT) {
36 if (openCnt > 0) {
37 ret = -EALREADY;
38 } else {
39 openCnt++;
40 ret = 0;
41 }
42 }
43 preempt_enable();
44 return ret;
45 }
46
gio_close(struct inode * inode,struct file * filp)47 static int gio_close(struct inode *inode, struct file *filp)
48 {
49 int minor;
50
51 minor = MINOR(inode->i_rdev);
52 if (minor < DEVCOUNT) {
53 openCnt--;
54 }
55 return 0;
56 }
57
gio_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)58 static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
59 {
60 unsigned int data;
61 static unsigned int addr = 0;
62
63 if (cmd & 0x01) { /* write */
64 if (copy_from_user(&data, (int *)arg, sizeof(int))) {
65 return -EFAULT;
66 }
67 }
68
69 switch (cmd) {
70 case GIODRV_IOCSGIOSETADDR: /* address set */
71 addr = data;
72 break;
73
74 case GIODRV_IOCSGIODATA1: /* write byte */
75 __raw_writeb((unsigned char)(0x0ff & data), addr);
76 break;
77
78 case GIODRV_IOCSGIODATA2: /* write word */
79 if (addr & 0x01) {
80 return -EFAULT;
81 }
82 __raw_writew((unsigned short int)(0x0ffff & data), addr);
83 break;
84
85 case GIODRV_IOCSGIODATA4: /* write long */
86 if (addr & 0x03) {
87 return -EFAULT;
88 }
89 __raw_writel(data, addr);
90 break;
91
92 case GIODRV_IOCGGIODATA1: /* read byte */
93 data = __raw_readb(addr);
94 break;
95
96 case GIODRV_IOCGGIODATA2: /* read word */
97 if (addr & 0x01) {
98 return -EFAULT;
99 }
100 data = __raw_readw(addr);
101 break;
102
103 case GIODRV_IOCGGIODATA4: /* read long */
104 if (addr & 0x03) {
105 return -EFAULT;
106 }
107 data = __raw_readl(addr);
108 break;
109 default:
110 return -EFAULT;
111 break;
112 }
113
114 if ((cmd & 0x01) == 0) { /* read */
115 if (copy_to_user((int *)arg, &data, sizeof(int))) {
116 return -EFAULT;
117 }
118 }
119 return 0;
120 }
121
122 static const struct file_operations gio_fops = {
123 .owner = THIS_MODULE,
124 .open = gio_open, /* open */
125 .release = gio_close, /* release */
126 .unlocked_ioctl = gio_ioctl,
127 .llseek = noop_llseek,
128 };
129
gio_init(void)130 static int __init gio_init(void)
131 {
132 int error;
133
134 printk(KERN_INFO "gio: driver initialized\n");
135
136 openCnt = 0;
137
138 if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
139 printk(KERN_ERR
140 "gio: Couldn't alloc_chrdev_region, error=%d\n",
141 error);
142 return 1;
143 }
144
145 cdev_p = cdev_alloc();
146 cdev_p->ops = &gio_fops;
147 error = cdev_add(cdev_p, dev, DEVCOUNT);
148 if (error) {
149 printk(KERN_ERR
150 "gio: Couldn't cdev_add, error=%d\n", error);
151 return 1;
152 }
153
154 return 0;
155 }
156
gio_exit(void)157 static void __exit gio_exit(void)
158 {
159 cdev_del(cdev_p);
160 unregister_chrdev_region(dev, DEVCOUNT);
161 }
162
163 module_init(gio_init);
164 module_exit(gio_exit);
165
166 MODULE_LICENSE("GPL");
167