aboutsummaryrefslogtreecommitdiff
path: root/drivers/macintosh/ans-lcd.c
blob: fa904b24a600a4b0754372ad0220accb732fc128 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
// SPDX-License-Identifier: GPL-2.0
/*
 * /dev/lcd driver for Apple Network Servers.
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/miscdevice.h>
#include <linux/fcntl.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/of.h>

#include <linux/uaccess.h>
#include <asm/sections.h>
#include <asm/io.h>

#include "ans-lcd.h"

#define ANSLCD_ADDR		0xf301c000
#define ANSLCD_CTRL_IX 0x00
#define ANSLCD_DATA_IX 0x10

static unsigned long anslcd_short_delay = 80;
static unsigned long anslcd_long_delay = 3280;
static volatile unsigned char __iomem *anslcd_ptr;
static DEFINE_MUTEX(anslcd_mutex);

#undef DEBUG

static void
anslcd_write_byte_ctrl ( unsigned char c )
{
#ifdef DEBUG
	printk(KERN_DEBUG "LCD: CTRL byte: %02x\n",c);
#endif
	out_8(anslcd_ptr + ANSLCD_CTRL_IX, c);
	switch(c) {
		case 1:
		case 2:
		case 3:
			udelay(anslcd_long_delay); break;
		default: udelay(anslcd_short_delay);
	}
}

static void
anslcd_write_byte_data ( unsigned char c )
{
	out_8(anslcd_ptr + ANSLCD_DATA_IX, c);
	udelay(anslcd_short_delay);
}

static ssize_t
anslcd_write( struct file * file, const char __user * buf, 
				size_t count, loff_t *ppos )
{
	const char __user *p = buf;
	int i;

#ifdef DEBUG
	printk(KERN_DEBUG "LCD: write\n");
#endif

	if (!access_ok(buf, count))
		return -EFAULT;

	mutex_lock(&anslcd_mutex);
	for ( i = *ppos; count > 0; ++i, ++p, --count ) 
	{
		char c;
		__get_user(c, p);
		anslcd_write_byte_data( c );
	}
	mutex_unlock(&anslcd_mutex);
	*ppos = i;
	return p - buf;
}

static long
anslcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	char ch, __user *temp;
	long ret = 0;

#ifdef DEBUG
	printk(KERN_DEBUG "LCD: ioctl(%d,%d)\n",cmd,arg);
#endif

	mutex_lock(&anslcd_mutex);

	switch ( cmd )
	{
	case ANSLCD_CLEAR:
		anslcd_write_byte_ctrl ( 0x38 );
		anslcd_write_byte_ctrl ( 0x0f );
		anslcd_write_byte_ctrl ( 0x06 );
		anslcd_write_byte_ctrl ( 0x01 );
		anslcd_write_byte_ctrl ( 0x02 );
		break;
	case ANSLCD_SENDCTRL:
		temp = (char __user *) arg;
		__get_user(ch, temp);
		for (; ch; temp++) { /* FIXME: This is ugly, but should work, as a \0 byte is not a valid command code */
			anslcd_write_byte_ctrl ( ch );
			__get_user(ch, temp);
		}
		break;
	case ANSLCD_SETSHORTDELAY:
		if (!capable(CAP_SYS_ADMIN))
			ret =-EACCES;
		else
			anslcd_short_delay=arg;
		break;
	case ANSLCD_SETLONGDELAY:
		if (!capable(CAP_SYS_ADMIN))
			ret = -EACCES;
		else
			anslcd_long_delay=arg;
		break;
	default:
		ret = -EINVAL;
	}

	mutex_unlock(&anslcd_mutex);
	return ret;
}

static int
anslcd_open( struct inode * inode, struct file * file )
{
	return 0;
}

const struct file_operations anslcd_fops = {
	.write		= anslcd_write,
	.unlocked_ioctl	= anslcd_ioctl,
	.open		= anslcd_open,
	.llseek		= default_llseek,
};

static struct miscdevice anslcd_dev = {
	LCD_MINOR,
	"anslcd",
	&anslcd_fops
};

static const char anslcd_logo[] __initconst =
				"********************"  /* Line #1 */
				"*      LINUX!      *"  /* Line #3 */
				"*    Welcome to    *"  /* Line #2 */
				"********************"; /* Line #4 */

static int __init
anslcd_init(void)
{
	int a;
	int retval;
	struct device_node* node;

	node = of_find_node_by_name(NULL, "lcd");
	if (!node || !of_node_name_eq(node->parent, "gc")) {
		of_node_put(node);
		return -ENODEV;
	}
	of_node_put(node);

	anslcd_ptr = ioremap(ANSLCD_ADDR, 0x20);
	
	retval = misc_register(&anslcd_dev);
	if(retval < 0){
		printk(KERN_INFO "LCD: misc_register failed\n");
		iounmap(anslcd_ptr);
		return retval;
	}

#ifdef DEBUG
	printk(KERN_DEBUG "LCD: init\n");
#endif

	mutex_lock(&anslcd_mutex);
	anslcd_write_byte_ctrl ( 0x38 );
	anslcd_write_byte_ctrl ( 0x0c );
	anslcd_write_byte_ctrl ( 0x06 );
	anslcd_write_byte_ctrl ( 0x01 );
	anslcd_write_byte_ctrl ( 0x02 );
	for(a=0;a<80;a++) {
		anslcd_write_byte_data(anslcd_logo[a]);
	}
	mutex_unlock(&anslcd_mutex);
	return 0;
}

static void __exit
anslcd_exit(void)
{
	misc_deregister(&anslcd_dev);
	iounmap(anslcd_ptr);
}

module_init(anslcd_init);
module_exit(anslcd_exit);
MODULE_LICENSE("GPL v2");