xref: /openbmc/linux/arch/sh/boards/mach-landisk/gio.c (revision 6f24784f)
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 = iminor(inode);
31 	int ret = -ENOENT;
32 
33 	preempt_disable();
34 	if (minor < DEVCOUNT) {
35 		if (openCnt > 0) {
36 			ret = -EALREADY;
37 		} else {
38 			openCnt++;
39 			ret = 0;
40 		}
41 	}
42 	preempt_enable();
43 	return ret;
44 }
45 
gio_close(struct inode * inode,struct file * filp)46 static int gio_close(struct inode *inode, struct file *filp)
47 {
48 	int minor = iminor(inode);
49 
50 	if (minor < DEVCOUNT) {
51 		openCnt--;
52 	}
53 	return 0;
54 }
55 
gio_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)56 static long gio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
57 {
58 	unsigned int data;
59 	static unsigned int addr = 0;
60 
61 	if (cmd & 0x01) {	/* write */
62 		if (copy_from_user(&data, (int *)arg, sizeof(int))) {
63 			return -EFAULT;
64 		}
65 	}
66 
67 	switch (cmd) {
68 	case GIODRV_IOCSGIOSETADDR:	/* address set */
69 		addr = data;
70 		break;
71 
72 	case GIODRV_IOCSGIODATA1:	/* write byte */
73 		__raw_writeb((unsigned char)(0x0ff & data), addr);
74 		break;
75 
76 	case GIODRV_IOCSGIODATA2:	/* write word */
77 		if (addr & 0x01) {
78 			return -EFAULT;
79 		}
80 		__raw_writew((unsigned short int)(0x0ffff & data), addr);
81 		break;
82 
83 	case GIODRV_IOCSGIODATA4:	/* write long */
84 		if (addr & 0x03) {
85 			return -EFAULT;
86 		}
87 		__raw_writel(data, addr);
88 		break;
89 
90 	case GIODRV_IOCGGIODATA1:	/* read byte */
91 		data = __raw_readb(addr);
92 		break;
93 
94 	case GIODRV_IOCGGIODATA2:	/* read word */
95 		if (addr & 0x01) {
96 			return -EFAULT;
97 		}
98 		data = __raw_readw(addr);
99 		break;
100 
101 	case GIODRV_IOCGGIODATA4:	/* read long */
102 		if (addr & 0x03) {
103 			return -EFAULT;
104 		}
105 		data = __raw_readl(addr);
106 		break;
107 	default:
108 		return -EFAULT;
109 		break;
110 	}
111 
112 	if ((cmd & 0x01) == 0) {	/* read */
113 		if (copy_to_user((int *)arg, &data, sizeof(int))) {
114 			return -EFAULT;
115 		}
116 	}
117 	return 0;
118 }
119 
120 static const struct file_operations gio_fops = {
121 	.owner = THIS_MODULE,
122 	.open = gio_open,	/* open */
123 	.release = gio_close,	/* release */
124 	.unlocked_ioctl = gio_ioctl,
125 	.llseek = noop_llseek,
126 };
127 
gio_init(void)128 static int __init gio_init(void)
129 {
130 	int error;
131 
132 	printk(KERN_INFO "gio: driver initialized\n");
133 
134 	openCnt = 0;
135 
136 	if ((error = alloc_chrdev_region(&dev, 0, DEVCOUNT, "gio")) < 0) {
137 		printk(KERN_ERR
138 		       "gio: Couldn't alloc_chrdev_region, error=%d\n",
139 		       error);
140 		return 1;
141 	}
142 
143 	cdev_p = cdev_alloc();
144 	cdev_p->ops = &gio_fops;
145 	error = cdev_add(cdev_p, dev, DEVCOUNT);
146 	if (error) {
147 		printk(KERN_ERR
148 		       "gio: Couldn't cdev_add, error=%d\n", error);
149 		return 1;
150 	}
151 
152 	return 0;
153 }
154 
gio_exit(void)155 static void __exit gio_exit(void)
156 {
157 	cdev_del(cdev_p);
158 	unregister_chrdev_region(dev, DEVCOUNT);
159 }
160 
161 module_init(gio_init);
162 module_exit(gio_exit);
163 
164 MODULE_LICENSE("GPL");
165