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
24static dev_t dev;
25static struct cdev *cdev_p;
26static int openCnt;
27
28static 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
47static 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
58static 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
122static 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
130static 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
157static void __exit gio_exit(void)
158{
159	cdev_del(cdev_p);
160	unregister_chrdev_region(dev, DEVCOUNT);
161}
162
163module_init(gio_init);
164module_exit(gio_exit);
165
166MODULE_LICENSE("GPL");
167