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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
/* $Id: display7seg.c,v 1.6 2002/01/08 16:00:16 davem Exp $
*
* display7seg - Driver implementation for the 7-segment display
* present on Sun Microsystems CP1400 and CP1500
*
* Copyright (c) 2000 Eric Brower (ebrower@usa.net)
*
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/major.h>
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/ioport.h> /* request_region */
#include <linux/smp_lock.h>
#include <asm/atomic.h>
#include <asm/ebus.h> /* EBus device */
#include <asm/oplib.h> /* OpenProm Library */
#include <asm/uaccess.h> /* put_/get_user */
#include <asm/io.h>
#include <asm/display7seg.h>
#define D7S_MINOR 193
#define D7S_OBPNAME "display7seg"
#define D7S_DEVNAME "d7s"
static int sol_compat = 0; /* Solaris compatibility mode */
#ifdef MODULE
/* Solaris compatibility flag -
* The Solaris implementation omits support for several
* documented driver features (ref Sun doc 806-0180-03).
* By default, this module supports the documented driver
* abilities, rather than the Solaris implementation:
*
* 1) Device ALWAYS reverts to OBP-specified FLIPPED mode
* upon closure of device or module unload.
* 2) Device ioctls D7SIOCRD/D7SIOCWR honor toggling of
* FLIP bit
*
* If you wish the device to operate as under Solaris,
* omitting above features, set this parameter to non-zero.
*/
module_param
(sol_compat, int, 0);
MODULE_PARM_DESC
(sol_compat,
"Disables documented functionality omitted from Solaris driver");
MODULE_AUTHOR
("Eric Brower <ebrower@usa.net>");
MODULE_DESCRIPTION
("7-Segment Display driver for Sun Microsystems CP1400/1500");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE
("d7s");
#endif /* ifdef MODULE */
/*
* Register block address- see header for details
* -----------------------------------------
* | DP | ALARM | FLIP | 4 | 3 | 2 | 1 | 0 |
* -----------------------------------------
*
* DP - Toggles decimal point on/off
* ALARM - Toggles "Alarm" LED green/red
* FLIP - Inverts display for upside-down mounted board
* bits 0-4 - 7-segment display contents
*/
static void __iomem* d7s_regs;
static inline void d7s_free(void)
{
iounmap(d7s_regs);
}
static inline int d7s_obpflipped(void)
{
int opt_node;
opt_node = prom_getchild(prom_root_node);
opt_node = prom_searchsiblings(opt_node, "options");
return ((-1 != prom_getintdefault(opt_node, "d7s-flipped?", -1)) ? 0 : 1);
}
static atomic_t d7s_users = ATOMIC_INIT(0);
static int d7s_open(struct inode *inode, struct file *f)
{
if (D7S_MINOR != iminor(inode))
return -ENODEV;
cycle_kernel_lock();
atomic_inc(&d7s_users);
return 0;
}
static int d7s_release(struct inode *inode, struct file *f)
{
/* Reset flipped state to OBP default only if
* no other users have the device open and we
* are not operating in solaris-compat mode
*/
if (atomic_dec_and_test(&d7s_users) && !sol_compat) {
int regval = 0;
regval = readb(d7s_regs);
(0 == d7s_obpflipped()) ?
writeb(regval |= D7S_FLIP, d7s_regs):
writeb(regval &= ~D7S_FLIP, d7s_regs);
}
return 0;
}
static long d7s_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
__u8 regs = readb(d7s_regs);
__u8 ireg = 0;
int error = 0;
if (D7S_MINOR != iminor(file->f_path.dentry->d_inode))
return -ENODEV;
lock_kernel();
switch (cmd) {
case D7SIOCWR:
/* assign device register values
* we mask-out D7S_FLIP if in sol_compat mode
*/
if (get_user(ireg, (int __user *) arg)) {
error = -EFAULT;
break;
}
if (0 != sol_compat) {
(regs & D7S_FLIP) ?
(ireg |= D7S_FLIP) : (ireg &= ~D7S_FLIP);
}
writeb(ireg, d7s_regs);
break;
case D7SIOCRD:
/* retrieve device register values
* NOTE: Solaris implementation returns D7S_FLIP bit
* as toggled by user, even though it does not honor it.
* This driver will not misinform you about the state
* of your hardware while in sol_compat mode
*/
if (put_user(regs, (int __user *) arg)) {
error = -EFAULT;
break;
}
break;
case D7SIOCTM:
/* toggle device mode-- flip display orientation */
(regs & D7S_FLIP) ?
(regs &= ~D7S_FLIP) : (regs |= D7S_FLIP);
writeb(regs, d7s_regs);
break;
};
unlock_kernel();
return error;
}
static const struct file_operations d7s_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = d7s_ioctl,
.compat_ioctl = d7s_ioctl,
.open = d7s_open,
.release = d7s_release,
};
static struct miscdevice d7s_miscdev = { D7S_MINOR, D7S_DEVNAME, &d7s_fops };
static int __init d7s_init(void)
{
struct linux_ebus *ebus = NULL;
struct linux_ebus_device *edev = NULL;
int iTmp = 0, regs = 0;
for_each_ebus(ebus) {
for_each_ebusdev(edev, ebus) {
if (!strcmp(edev->prom_node->name, D7S_OBPNAME))
goto ebus_done;
}
}
ebus_done:
if(!edev) {
printk("%s: unable to locate device\n", D7S_DEVNAME);
return -ENODEV;
}
d7s_regs = ioremap(edev->resource[0].start, sizeof(__u8));
iTmp = misc_register(&d7s_miscdev);
if (0 != iTmp) {
printk("%s: unable to acquire miscdevice minor %i\n",
D7S_DEVNAME, D7S_MINOR);
iounmap(d7s_regs);
return iTmp;
}
/* OBP option "d7s-flipped?" is honored as default
* for the device, and reset default when detached
*/
regs = readb(d7s_regs);
iTmp = d7s_obpflipped();
(0 == iTmp) ?
writeb(regs |= D7S_FLIP, d7s_regs):
writeb(regs &= ~D7S_FLIP, d7s_regs);
printk("%s: 7-Segment Display%s at 0x%lx %s\n",
D7S_DEVNAME,
(0 == iTmp) ? (" (FLIPPED)") : (""),
edev->resource[0].start,
(0 != sol_compat) ? ("in sol_compat mode") : (""));
return 0;
}
static void __exit d7s_cleanup(void)
{
int regs = readb(d7s_regs);
/* Honor OBP d7s-flipped? unless operating in solaris-compat mode */
if (0 == sol_compat) {
(0 == d7s_obpflipped()) ?
writeb(regs |= D7S_FLIP, d7s_regs):
writeb(regs &= ~D7S_FLIP, d7s_regs);
}
misc_deregister(&d7s_miscdev);
d7s_free();
}
module_init(d7s_init);
module_exit(d7s_cleanup);
|
