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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
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
42static unsigned int ks0108_port = CONFIG_KS0108_PORT;
43module_param(ks0108_port, uint, S_IRUGO);
44MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected");
45
46static unsigned int ks0108_delay = CONFIG_KS0108_DELAY;
47module_param(ks0108_delay, uint, S_IRUGO);
48MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)");
49
50/*
51 * Device
52 */
53
54static struct parport *ks0108_parport;
55static 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
75void ks0108_writedata(unsigned char byte)
76{
77 parport_write_data(ks0108_parport, byte);
78}
79
80void 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
86void 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
91void ks0108_startline(unsigned char startline)
92{
93 ks0108_writedata(min(startline,(unsigned char)63) | bit(6) | bit(7));
94}
95
96void ks0108_address(unsigned char address)
97{
98 ks0108_writedata(min(address,(unsigned char)63) | bit(6));
99}
100
101void ks0108_page(unsigned char page)
102{
103 ks0108_writedata(min(page,(unsigned char)7) | bit(3) | bit(4) | bit(5) | bit(7));
104}
105
106EXPORT_SYMBOL_GPL(ks0108_writedata);
107EXPORT_SYMBOL_GPL(ks0108_writecontrol);
108EXPORT_SYMBOL_GPL(ks0108_displaystate);
109EXPORT_SYMBOL_GPL(ks0108_startline);
110EXPORT_SYMBOL_GPL(ks0108_address);
111EXPORT_SYMBOL_GPL(ks0108_page);
112
113/*
114 * Is the module inited?
115 */
116
117static unsigned char ks0108_inited;
118unsigned char ks0108_isinited(void)
119{
120 return ks0108_inited;
121}
122EXPORT_SYMBOL_GPL(ks0108_isinited);
123
124/*
125 * Module Init & Exit
126 */
127
128static int __init ks0108_init(void)
129{
130 int result;
131 int ret = -EINVAL;
132
133 ks0108_parport = parport_find_base(ks0108_port);
134 if (ks0108_parport == NULL) {
135 printk(KERN_ERR KS0108_NAME ": ERROR: "
136 "parport didn't find %i port\n", ks0108_port);
137 goto none;
138 }
139
140 ks0108_pardevice = parport_register_device(ks0108_parport, KS0108_NAME,
141 NULL, NULL, NULL, PARPORT_DEV_EXCL, NULL);
142 if (ks0108_pardevice == NULL) {
143 printk(KERN_ERR KS0108_NAME ": ERROR: "
144 "parport didn't register new device\n");
145 goto none;
146 }
147
148 result = parport_claim(ks0108_pardevice);
149 if (result != 0) {
150 printk(KERN_ERR KS0108_NAME ": ERROR: "
151 "can't claim %i parport, maybe in use\n", ks0108_port);
152 ret = result;
153 goto registered;
154 }
155
156 ks0108_inited = 1;
157 return 0;
158
159registered:
160 parport_unregister_device(ks0108_pardevice);
161
162none:
163 return ret;
164}
165
166static void __exit ks0108_exit(void)
167{
168 parport_release(ks0108_pardevice);
169 parport_unregister_device(ks0108_pardevice);
170}
171
172module_init(ks0108_init);
173module_exit(ks0108_exit);
174
175MODULE_LICENSE("GPL v2");
176MODULE_AUTHOR("Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>");
177MODULE_DESCRIPTION("ks0108 LCD Controller driver");
178
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
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
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
44static unsigned int ks0108_port = CONFIG_KS0108_PORT;
45module_param(ks0108_port, uint, S_IRUGO);
46MODULE_PARM_DESC(ks0108_port, "Parallel port where the LCD is connected");
47
48static unsigned int ks0108_delay = CONFIG_KS0108_DELAY;
49module_param(ks0108_delay, uint, S_IRUGO);
50MODULE_PARM_DESC(ks0108_delay, "Delay between each control writing (microseconds)");
51
52/*
53 * Device
54 */
55
56static struct parport *ks0108_parport;
57static 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
77void ks0108_writedata(unsigned char byte)
78{
79 parport_write_data(ks0108_parport, byte);
80}
81
82void 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
88void 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
93void ks0108_startline(unsigned char startline)
94{
95 ks0108_writedata(min_t(unsigned char, startline, 63) | bit(6) |
96 bit(7));
97}
98
99void ks0108_address(unsigned char address)
100{
101 ks0108_writedata(min_t(unsigned char, address, 63) | bit(6));
102}
103
104void ks0108_page(unsigned char page)
105{
106 ks0108_writedata(min_t(unsigned char, page, 7) | bit(3) | bit(4) |
107 bit(5) | bit(7));
108}
109
110EXPORT_SYMBOL_GPL(ks0108_writedata);
111EXPORT_SYMBOL_GPL(ks0108_writecontrol);
112EXPORT_SYMBOL_GPL(ks0108_displaystate);
113EXPORT_SYMBOL_GPL(ks0108_startline);
114EXPORT_SYMBOL_GPL(ks0108_address);
115EXPORT_SYMBOL_GPL(ks0108_page);
116
117/*
118 * Is the module inited?
119 */
120
121static unsigned char ks0108_inited;
122unsigned char ks0108_isinited(void)
123{
124 return ks0108_inited;
125}
126EXPORT_SYMBOL_GPL(ks0108_isinited);
127
128static void ks0108_parport_attach(struct parport *port)
129{
130 struct pardev_cb ks0108_cb;
131
132 if (port->base != ks0108_port)
133 return;
134
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) {
140 pr_err("ERROR: parport didn't register new device\n");
141 return;
142 }
143 if (parport_claim(ks0108_pardevice)) {
144 pr_err("could not claim access to parport %i. Aborting.\n",
145 ks0108_port);
146 goto err_unreg_device;
147 }
148
149 ks0108_parport = port;
150 ks0108_inited = 1;
151 return;
152
153err_unreg_device:
154 parport_unregister_device(ks0108_pardevice);
155 ks0108_pardevice = NULL;
156}
157
158static void ks0108_parport_detach(struct parport *port)
159{
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
168 parport_release(ks0108_pardevice);
169 parport_unregister_device(ks0108_pardevice);
170 ks0108_pardevice = NULL;
171 ks0108_parport = NULL;
172}
173
174/*
175 * Module Init & Exit
176 */
177
178static 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
185static int __init ks0108_init(void)
186{
187 return parport_register_driver(&ks0108_parport_driver);
188}
189
190static void __exit ks0108_exit(void)
191{
192 parport_unregister_driver(&ks0108_parport_driver);
193}
194
195module_init(ks0108_init);
196module_exit(ks0108_exit);
197
198MODULE_LICENSE("GPL v2");
199MODULE_AUTHOR("Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>");
200MODULE_DESCRIPTION("ks0108 LCD Controller driver");
201