Commit | Line | Data |
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70e84049 MOS |
1 | /* |
2 | * Filename: ks0108.c | |
3 | * Version: 0.1.0 | |
4 | * Description: ks0108 LCD Controller driver | |
5 | * License: GPLv2 | |
6 | * Depends: parport | |
7 | * | |
450c622e | 8 | * Author: Copyright (C) Miguel Ojeda Sandonis |
70e84049 MOS |
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 | ||
7faad1df SM |
26 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
27 | ||
70e84049 MOS |
28 | #include <linux/init.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/kernel.h> | |
31 | #include <linux/delay.h> | |
32 | #include <linux/fs.h> | |
33 | #include <linux/io.h> | |
34 | #include <linux/parport.h> | |
35 | #include <linux/uaccess.h> | |
36 | #include <linux/ks0108.h> | |
37 | ||
38 | #define KS0108_NAME "ks0108" | |
39 | ||
40 | /* | |
41 | * Module Parameters | |
42 | */ | |
43 | ||
44 | static unsigned int ks0108_port = CONFIG_KS0108_PORT; | |
45 | module_param(ks0108_port, uint, S_IRUGO); | |
46 | MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected"); | |
47 | ||
48 | static unsigned int ks0108_delay = CONFIG_KS0108_DELAY; | |
49 | module_param(ks0108_delay, uint, S_IRUGO); | |
50 | MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)"); | |
51 | ||
52 | /* | |
53 | * Device | |
54 | */ | |
55 | ||
56 | static struct parport *ks0108_parport; | |
57 | static struct pardevice *ks0108_pardevice; | |
58 | ||
59 | /* | |
60 | * ks0108 Exported Commands (don't lock) | |
61 | * | |
62 | * You _should_ lock in the top driver: This functions _should not_ | |
63 | * get race conditions in any way. Locking for each byte here would be | |
64 | * so slow and useless. | |
65 | * | |
66 | * There are not bit definitions because they are not flags, | |
67 | * just arbitrary combinations defined by the documentation for each | |
68 | * function in the ks0108 LCD controller. If you want to know what means | |
69 | * a specific combination, look at the function's name. | |
70 | * | |
71 | * The ks0108_writecontrol bits need to be reverted ^(0,1,3) because | |
72 | * the parallel port also revert them using a "not" logic gate. | |
73 | */ | |
74 | ||
75 | #define bit(n) (((unsigned char)1)<<(n)) | |
76 | ||
77 | void ks0108_writedata(unsigned char byte) | |
78 | { | |
79 | parport_write_data(ks0108_parport, byte); | |
80 | } | |
81 | ||
82 | void ks0108_writecontrol(unsigned char byte) | |
83 | { | |
84 | udelay(ks0108_delay); | |
85 | parport_write_control(ks0108_parport, byte ^ (bit(0) | bit(1) | bit(3))); | |
86 | } | |
87 | ||
88 | void ks0108_displaystate(unsigned char state) | |
89 | { | |
90 | ks0108_writedata((state ? bit(0) : 0) | bit(1) | bit(2) | bit(3) | bit(4) | bit(5)); | |
91 | } | |
92 | ||
93 | void ks0108_startline(unsigned char startline) | |
94 | { | |
c9efdbe6 SM |
95 | ks0108_writedata(min_t(unsigned char, startline, 63) | bit(6) | |
96 | bit(7)); | |
70e84049 MOS |
97 | } |
98 | ||
99 | void ks0108_address(unsigned char address) | |
100 | { | |
c9efdbe6 | 101 | ks0108_writedata(min_t(unsigned char, address, 63) | bit(6)); |
70e84049 MOS |
102 | } |
103 | ||
104 | void ks0108_page(unsigned char page) | |
105 | { | |
c9efdbe6 SM |
106 | ks0108_writedata(min_t(unsigned char, page, 7) | bit(3) | bit(4) | |
107 | bit(5) | bit(7)); | |
70e84049 MOS |
108 | } |
109 | ||
110 | EXPORT_SYMBOL_GPL(ks0108_writedata); | |
111 | EXPORT_SYMBOL_GPL(ks0108_writecontrol); | |
112 | EXPORT_SYMBOL_GPL(ks0108_displaystate); | |
113 | EXPORT_SYMBOL_GPL(ks0108_startline); | |
114 | EXPORT_SYMBOL_GPL(ks0108_address); | |
115 | EXPORT_SYMBOL_GPL(ks0108_page); | |
116 | ||
34173a4a MO |
117 | /* |
118 | * Is the module inited? | |
119 | */ | |
120 | ||
121 | static unsigned char ks0108_inited; | |
122 | unsigned char ks0108_isinited(void) | |
123 | { | |
124 | return ks0108_inited; | |
125 | } | |
126 | EXPORT_SYMBOL_GPL(ks0108_isinited); | |
127 | ||
4edd70c1 | 128 | static void ks0108_parport_attach(struct parport *port) |
70e84049 | 129 | { |
4edd70c1 | 130 | struct pardev_cb ks0108_cb; |
70e84049 | 131 | |
4edd70c1 SM |
132 | if (port->base != ks0108_port) |
133 | return; | |
70e84049 | 134 | |
4edd70c1 SM |
135 | memset(&ks0108_cb, 0, sizeof(ks0108_cb)); |
136 | ks0108_cb.flags = PARPORT_DEV_EXCL; | |
137 | ks0108_pardevice = parport_register_dev_model(port, KS0108_NAME, | |
138 | &ks0108_cb, 0); | |
139 | if (!ks0108_pardevice) { | |
7faad1df | 140 | pr_err("ERROR: parport didn't register new device\n"); |
4edd70c1 | 141 | return; |
70e84049 | 142 | } |
4edd70c1 SM |
143 | if (parport_claim(ks0108_pardevice)) { |
144 | pr_err("could not claim access to parport %i. Aborting.\n", | |
7faad1df | 145 | ks0108_port); |
4edd70c1 | 146 | goto err_unreg_device; |
70e84049 MOS |
147 | } |
148 | ||
92f26189 | 149 | ks0108_parport = port; |
34173a4a | 150 | ks0108_inited = 1; |
4edd70c1 | 151 | return; |
70e84049 | 152 | |
4edd70c1 | 153 | err_unreg_device: |
70e84049 | 154 | parport_unregister_device(ks0108_pardevice); |
4edd70c1 | 155 | ks0108_pardevice = NULL; |
70e84049 MOS |
156 | } |
157 | ||
4edd70c1 | 158 | static void ks0108_parport_detach(struct parport *port) |
70e84049 | 159 | { |
4edd70c1 SM |
160 | if (port->base != ks0108_port) |
161 | return; | |
162 | ||
163 | if (!ks0108_pardevice) { | |
164 | pr_err("%s: already unregistered.\n", KS0108_NAME); | |
165 | return; | |
166 | } | |
167 | ||
70e84049 MOS |
168 | parport_release(ks0108_pardevice); |
169 | parport_unregister_device(ks0108_pardevice); | |
4edd70c1 | 170 | ks0108_pardevice = NULL; |
92f26189 | 171 | ks0108_parport = NULL; |
4edd70c1 SM |
172 | } |
173 | ||
174 | /* | |
175 | * Module Init & Exit | |
176 | */ | |
177 | ||
178 | static struct parport_driver ks0108_parport_driver = { | |
179 | .name = "ks0108", | |
180 | .match_port = ks0108_parport_attach, | |
181 | .detach = ks0108_parport_detach, | |
182 | .devmodel = true, | |
183 | }; | |
184 | ||
185 | static int __init ks0108_init(void) | |
186 | { | |
187 | return parport_register_driver(&ks0108_parport_driver); | |
188 | } | |
189 | ||
190 | static void __exit ks0108_exit(void) | |
191 | { | |
192 | parport_unregister_driver(&ks0108_parport_driver); | |
70e84049 MOS |
193 | } |
194 | ||
195 | module_init(ks0108_init); | |
196 | module_exit(ks0108_exit); | |
197 | ||
198 | MODULE_LICENSE("GPL v2"); | |
450c622e | 199 | MODULE_AUTHOR("Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>"); |
70e84049 MOS |
200 | MODULE_DESCRIPTION("ks0108 LCD Controller driver"); |
201 |