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 = 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
46static 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
56static 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(to: &data, from: (int *)arg, n: 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(val: (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(val: (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(val: 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(to: (int *)arg, from: &data, n: sizeof(int))) {
114 return -EFAULT;
115 }
116 }
117 return 0;
118}
119
120static 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
128static 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
155static void __exit gio_exit(void)
156{
157 cdev_del(cdev_p);
158 unregister_chrdev_region(dev, DEVCOUNT);
159}
160
161module_init(gio_init);
162module_exit(gio_exit);
163
164MODULE_LICENSE("GPL");
165

source code of linux/arch/sh/boards/mach-landisk/gio.c