diff options
Diffstat (limited to 'drivers/auxdisplay/ks0108.c')
-rw-r--r-- | drivers/auxdisplay/ks0108.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/auxdisplay/ks0108.c b/drivers/auxdisplay/ks0108.c new file mode 100644 index 000000000000..a637575b9106 --- /dev/null +++ b/drivers/auxdisplay/ks0108.c | |||
@@ -0,0 +1,166 @@ | |||
1 | /* | ||
2 | * Filename: ks0108.c | ||
3 | * Version: 0.1.0 | ||
4 | * Description: ks0108 LCD Controller driver | ||
5 | * License: GPLv2 | ||
6 | * Depends: parport | ||
7 | * | ||
8 | * Author: Copyright (C) Miguel Ojeda Sandonis <maxextreme@gmail.com> | ||
9 | * Date: 2006-10-31 | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify | ||
12 | * it under the terms of the GNU General Public License version 2 as | ||
13 | * published by the Free Software Foundation. | ||
14 | * | ||
15 | * This program is distributed in the hope that it will be useful, | ||
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
18 | * GNU General Public License for more details. | ||
19 | * | ||
20 | * You should have received a copy of the GNU General Public License | ||
21 | * along with this program; if not, write to the Free Software | ||
22 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
23 | * | ||
24 | */ | ||
25 | |||
26 | #include <linux/init.h> | ||
27 | #include <linux/module.h> | ||
28 | #include <linux/kernel.h> | ||
29 | #include <linux/delay.h> | ||
30 | #include <linux/fs.h> | ||
31 | #include <linux/io.h> | ||
32 | #include <linux/parport.h> | ||
33 | #include <linux/uaccess.h> | ||
34 | #include <linux/ks0108.h> | ||
35 | |||
36 | #define KS0108_NAME "ks0108" | ||
37 | |||
38 | /* | ||
39 | * Module Parameters | ||
40 | */ | ||
41 | |||
42 | static unsigned int ks0108_port = CONFIG_KS0108_PORT; | ||
43 | module_param(ks0108_port, uint, S_IRUGO); | ||
44 | MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected"); | ||
45 | |||
46 | static unsigned int ks0108_delay = CONFIG_KS0108_DELAY; | ||
47 | module_param(ks0108_delay, uint, S_IRUGO); | ||
48 | MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)"); | ||
49 | |||
50 | /* | ||
51 | * Device | ||
52 | */ | ||
53 | |||
54 | static struct parport *ks0108_parport; | ||
55 | static struct pardevice *ks0108_pardevice; | ||
56 | |||
57 | /* | ||
58 | * ks0108 Exported Commands (don't lock) | ||
59 | * | ||
60 | * You _should_ lock in the top driver: This functions _should not_ | ||
61 | * get race conditions in any way. Locking for each byte here would be | ||
62 | * so slow and useless. | ||
63 | * | ||
64 | * There are not bit definitions because they are not flags, | ||
65 | * just arbitrary combinations defined by the documentation for each | ||
66 | * function in the ks0108 LCD controller. If you want to know what means | ||
67 | * a specific combination, look at the function's name. | ||
68 | * | ||
69 | * The ks0108_writecontrol bits need to be reverted ^(0,1,3) because | ||
70 | * the parallel port also revert them using a "not" logic gate. | ||
71 | */ | ||
72 | |||
73 | #define bit(n) (((unsigned char)1)<<(n)) | ||
74 | |||
75 | void ks0108_writedata(unsigned char byte) | ||
76 | { | ||
77 | parport_write_data(ks0108_parport, byte); | ||
78 | } | ||
79 | |||
80 | void ks0108_writecontrol(unsigned char byte) | ||
81 | { | ||
82 | udelay(ks0108_delay); | ||
83 | parport_write_control(ks0108_parport, byte ^ (bit(0) | bit(1) | bit(3))); | ||
84 | } | ||
85 | |||
86 | void ks0108_displaystate(unsigned char state) | ||
87 | { | ||
88 | ks0108_writedata((state ? bit(0) : 0) | bit(1) | bit(2) | bit(3) | bit(4) | bit(5)); | ||
89 | } | ||
90 | |||
91 | void ks0108_startline(unsigned char startline) | ||
92 | { | ||
93 | ks0108_writedata(min(startline,(unsigned char)63) | bit(6) | bit(7)); | ||
94 | } | ||
95 | |||
96 | void ks0108_address(unsigned char address) | ||
97 | { | ||
98 | ks0108_writedata(min(address,(unsigned char)63) | bit(6)); | ||
99 | } | ||
100 | |||
101 | void ks0108_page(unsigned char page) | ||
102 | { | ||
103 | ks0108_writedata(min(page,(unsigned char)7) | bit(3) | bit(4) | bit(5) | bit(7)); | ||
104 | } | ||
105 | |||
106 | EXPORT_SYMBOL_GPL(ks0108_writedata); | ||
107 | EXPORT_SYMBOL_GPL(ks0108_writecontrol); | ||
108 | EXPORT_SYMBOL_GPL(ks0108_displaystate); | ||
109 | EXPORT_SYMBOL_GPL(ks0108_startline); | ||
110 | EXPORT_SYMBOL_GPL(ks0108_address); | ||
111 | EXPORT_SYMBOL_GPL(ks0108_page); | ||
112 | |||
113 | /* | ||
114 | * Module Init & Exit | ||
115 | */ | ||
116 | |||
117 | static int __init ks0108_init(void) | ||
118 | { | ||
119 | int result; | ||
120 | int ret = -EINVAL; | ||
121 | |||
122 | ks0108_parport = parport_find_base(ks0108_port); | ||
123 | if (ks0108_parport == NULL) { | ||
124 | printk(KERN_ERR KS0108_NAME ": ERROR: " | ||
125 | "parport didn't find %i port\n", ks0108_port); | ||
126 | goto none; | ||
127 | } | ||
128 | |||
129 | ks0108_pardevice = parport_register_device(ks0108_parport, KS0108_NAME, | ||
130 | NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL); | ||
131 | if (ks0108_pardevice == NULL) { | ||
132 | printk(KERN_ERR KS0108_NAME ": ERROR: " | ||
133 | "parport didn't register new device\n"); | ||
134 | goto none; | ||
135 | } | ||
136 | |||
137 | result = parport_claim(ks0108_pardevice); | ||
138 | if (result != 0) { | ||
139 | printk(KERN_ERR KS0108_NAME ": ERROR: " | ||
140 | "can't claim %i parport, maybe in use\n", ks0108_port); | ||
141 | ret = result; | ||
142 | goto registered; | ||
143 | } | ||
144 | |||
145 | return 0; | ||
146 | |||
147 | registered: | ||
148 | parport_unregister_device(ks0108_pardevice); | ||
149 | |||
150 | none: | ||
151 | return ret; | ||
152 | } | ||
153 | |||
154 | static void __exit ks0108_exit(void) | ||
155 | { | ||
156 | parport_release(ks0108_pardevice); | ||
157 | parport_unregister_device(ks0108_pardevice); | ||
158 | } | ||
159 | |||
160 | module_init(ks0108_init); | ||
161 | module_exit(ks0108_exit); | ||
162 | |||
163 | MODULE_LICENSE("GPL v2"); | ||
164 | MODULE_AUTHOR("Miguel Ojeda Sandonis <maxextreme@gmail.com>"); | ||
165 | MODULE_DESCRIPTION("ks0108 LCD Controller driver"); | ||
166 | |||