xref: /openbmc/linux/arch/sh/boards/mach-landisk/gio.c (revision 9cfc5c90)
1 /*
2  * arch/sh/boards/landisk/gio.c - driver for landisk
3  *
4  * This driver will also support the I-O DATA Device, Inc. LANDISK Board.
5  * LANDISK and USL-5P Button, LED and GIO driver drive function.
6  *
7  *   Copylight (C) 2006 kogiidena
8  *   Copylight (C) 2002 Atom Create Engineering Co., Ltd. *
9  *
10  * This file is subject to the terms and conditions of the GNU General Public
11  * License.  See the file "COPYING" in the main directory of this archive
12  * for more details.
13  *
14  */
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	/* GIO minor no. */
27 
28 static dev_t dev;
29 static struct cdev *cdev_p;
30 static int openCnt;
31 
32 static 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 
51 static 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 
62 static 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) {	/* write */
68 		if (copy_from_user(&data, (int *)arg, sizeof(int))) {
69 			return -EFAULT;
70 		}
71 	}
72 
73 	switch (cmd) {
74 	case GIODRV_IOCSGIOSETADDR:	/* address set */
75 		addr = data;
76 		break;
77 
78 	case GIODRV_IOCSGIODATA1:	/* write byte */
79 		__raw_writeb((unsigned char)(0x0ff & data), addr);
80 		break;
81 
82 	case GIODRV_IOCSGIODATA2:	/* write word */
83 		if (addr & 0x01) {
84 			return -EFAULT;
85 		}
86 		__raw_writew((unsigned short int)(0x0ffff & data), addr);
87 		break;
88 
89 	case GIODRV_IOCSGIODATA4:	/* write long */
90 		if (addr & 0x03) {
91 			return -EFAULT;
92 		}
93 		__raw_writel(data, addr);
94 		break;
95 
96 	case GIODRV_IOCGGIODATA1:	/* read byte */
97 		data = __raw_readb(addr);
98 		break;
99 
100 	case GIODRV_IOCGGIODATA2:	/* read word */
101 		if (addr & 0x01) {
102 			return -EFAULT;
103 		}
104 		data = __raw_readw(addr);
105 		break;
106 
107 	case GIODRV_IOCGGIODATA4:	/* read long */
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) {	/* read */
119 		if (copy_to_user((int *)arg, &data, sizeof(int))) {
120 			return -EFAULT;
121 		}
122 	}
123 	return 0;
124 }
125 
126 static const struct file_operations gio_fops = {
127 	.owner = THIS_MODULE,
128 	.open = gio_open,	/* open */
129 	.release = gio_close,	/* release */
130 	.unlocked_ioctl = gio_ioctl,
131 	.llseek = noop_llseek,
132 };
133 
134 static 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 
161 static void __exit gio_exit(void)
162 {
163 	cdev_del(cdev_p);
164 	unregister_chrdev_region(dev, DEVCOUNT);
165 }
166 
167 module_init(gio_init);
168 module_exit(gio_exit);
169 
170 MODULE_LICENSE("GPL");
171