diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/w1/w1_io.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/w1/w1_io.c')
-rw-r--r-- | drivers/w1/w1_io.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c new file mode 100644 index 000000000000..02796b5a39f6 --- /dev/null +++ b/drivers/w1/w1_io.c | |||
@@ -0,0 +1,195 @@ | |||
1 | /* | ||
2 | * w1_io.c | ||
3 | * | ||
4 | * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru> | ||
5 | * | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License as published by | ||
9 | * the Free Software Foundation; either version 2 of the License, or | ||
10 | * (at your option) any later version. | ||
11 | * | ||
12 | * This program is distributed in the hope that it will be useful, | ||
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
15 | * GNU General Public License for more details. | ||
16 | * | ||
17 | * You should have received a copy of the GNU General Public License | ||
18 | * along with this program; if not, write to the Free Software | ||
19 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
20 | */ | ||
21 | |||
22 | #include <asm/io.h> | ||
23 | |||
24 | #include <linux/delay.h> | ||
25 | #include <linux/moduleparam.h> | ||
26 | |||
27 | #include "w1.h" | ||
28 | #include "w1_log.h" | ||
29 | #include "w1_io.h" | ||
30 | |||
31 | int w1_delay_parm = 1; | ||
32 | module_param_named(delay_coef, w1_delay_parm, int, 0); | ||
33 | |||
34 | static u8 w1_crc8_table[] = { | ||
35 | 0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65, | ||
36 | 157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220, | ||
37 | 35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98, | ||
38 | 190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255, | ||
39 | 70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7, | ||
40 | 219, 133, 103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154, | ||
41 | 101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36, | ||
42 | 248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185, | ||
43 | 140, 210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113, 147, 205, | ||
44 | 17, 79, 173, 243, 112, 46, 204, 146, 211, 141, 111, 49, 178, 236, 14, 80, | ||
45 | 175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82, 176, 238, | ||
46 | 50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115, | ||
47 | 202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139, | ||
48 | 87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22, | ||
49 | 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168, | ||
50 | 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53 | ||
51 | }; | ||
52 | |||
53 | void w1_delay(unsigned long tm) | ||
54 | { | ||
55 | udelay(tm * w1_delay_parm); | ||
56 | } | ||
57 | |||
58 | u8 w1_touch_bit(struct w1_master *dev, int bit) | ||
59 | { | ||
60 | if (dev->bus_master->touch_bit) | ||
61 | return dev->bus_master->touch_bit(dev->bus_master->data, bit); | ||
62 | else | ||
63 | return w1_read_bit(dev); | ||
64 | } | ||
65 | |||
66 | void w1_write_bit(struct w1_master *dev, int bit) | ||
67 | { | ||
68 | if (bit) { | ||
69 | dev->bus_master->write_bit(dev->bus_master->data, 0); | ||
70 | w1_delay(6); | ||
71 | dev->bus_master->write_bit(dev->bus_master->data, 1); | ||
72 | w1_delay(64); | ||
73 | } else { | ||
74 | dev->bus_master->write_bit(dev->bus_master->data, 0); | ||
75 | w1_delay(60); | ||
76 | dev->bus_master->write_bit(dev->bus_master->data, 1); | ||
77 | w1_delay(10); | ||
78 | } | ||
79 | } | ||
80 | |||
81 | void w1_write_8(struct w1_master *dev, u8 byte) | ||
82 | { | ||
83 | int i; | ||
84 | |||
85 | if (dev->bus_master->write_byte) | ||
86 | dev->bus_master->write_byte(dev->bus_master->data, byte); | ||
87 | else | ||
88 | for (i = 0; i < 8; ++i) | ||
89 | w1_write_bit(dev, (byte >> i) & 0x1); | ||
90 | } | ||
91 | |||
92 | u8 w1_read_bit(struct w1_master *dev) | ||
93 | { | ||
94 | int result; | ||
95 | |||
96 | dev->bus_master->write_bit(dev->bus_master->data, 0); | ||
97 | w1_delay(6); | ||
98 | dev->bus_master->write_bit(dev->bus_master->data, 1); | ||
99 | w1_delay(9); | ||
100 | |||
101 | result = dev->bus_master->read_bit(dev->bus_master->data); | ||
102 | w1_delay(55); | ||
103 | |||
104 | return result & 0x1; | ||
105 | } | ||
106 | |||
107 | u8 w1_read_8(struct w1_master * dev) | ||
108 | { | ||
109 | int i; | ||
110 | u8 res = 0; | ||
111 | |||
112 | if (dev->bus_master->read_byte) | ||
113 | res = dev->bus_master->read_byte(dev->bus_master->data); | ||
114 | else | ||
115 | for (i = 0; i < 8; ++i) | ||
116 | res |= (w1_read_bit(dev) << i); | ||
117 | |||
118 | return res; | ||
119 | } | ||
120 | |||
121 | void w1_write_block(struct w1_master *dev, u8 *buf, int len) | ||
122 | { | ||
123 | int i; | ||
124 | |||
125 | if (dev->bus_master->write_block) | ||
126 | dev->bus_master->write_block(dev->bus_master->data, buf, len); | ||
127 | else | ||
128 | for (i = 0; i < len; ++i) | ||
129 | w1_write_8(dev, buf[i]); | ||
130 | } | ||
131 | |||
132 | u8 w1_read_block(struct w1_master *dev, u8 *buf, int len) | ||
133 | { | ||
134 | int i; | ||
135 | u8 ret; | ||
136 | |||
137 | if (dev->bus_master->read_block) | ||
138 | ret = dev->bus_master->read_block(dev->bus_master->data, buf, len); | ||
139 | else { | ||
140 | for (i = 0; i < len; ++i) | ||
141 | buf[i] = w1_read_8(dev); | ||
142 | ret = len; | ||
143 | } | ||
144 | |||
145 | return ret; | ||
146 | } | ||
147 | |||
148 | int w1_reset_bus(struct w1_master *dev) | ||
149 | { | ||
150 | int result = 0; | ||
151 | |||
152 | if (dev->bus_master->reset_bus) | ||
153 | result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1; | ||
154 | else { | ||
155 | dev->bus_master->write_bit(dev->bus_master->data, 0); | ||
156 | w1_delay(480); | ||
157 | dev->bus_master->write_bit(dev->bus_master->data, 1); | ||
158 | w1_delay(70); | ||
159 | |||
160 | result = dev->bus_master->read_bit(dev->bus_master->data) & 0x1; | ||
161 | w1_delay(410); | ||
162 | } | ||
163 | |||
164 | return result; | ||
165 | } | ||
166 | |||
167 | u8 w1_calc_crc8(u8 * data, int len) | ||
168 | { | ||
169 | u8 crc = 0; | ||
170 | |||
171 | while (len--) | ||
172 | crc = w1_crc8_table[crc ^ *data++]; | ||
173 | |||
174 | return crc; | ||
175 | } | ||
176 | |||
177 | void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb) | ||
178 | { | ||
179 | dev->attempts++; | ||
180 | if (dev->bus_master->search) | ||
181 | dev->bus_master->search(dev->bus_master->data, cb); | ||
182 | else | ||
183 | w1_search(dev); | ||
184 | } | ||
185 | |||
186 | EXPORT_SYMBOL(w1_write_bit); | ||
187 | EXPORT_SYMBOL(w1_write_8); | ||
188 | EXPORT_SYMBOL(w1_read_bit); | ||
189 | EXPORT_SYMBOL(w1_read_8); | ||
190 | EXPORT_SYMBOL(w1_reset_bus); | ||
191 | EXPORT_SYMBOL(w1_calc_crc8); | ||
192 | EXPORT_SYMBOL(w1_delay); | ||
193 | EXPORT_SYMBOL(w1_read_block); | ||
194 | EXPORT_SYMBOL(w1_write_block); | ||
195 | EXPORT_SYMBOL(w1_search_devices); | ||