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15#include <asm/io.h>
16
17#include <linux/delay.h>
18#include <linux/moduleparam.h>
19#include <linux/module.h>
20
21#include "w1_internal.h"
22
23static int w1_delay_parm = 1;
24module_param_named(delay_coef, w1_delay_parm, int, 0);
25
26static int w1_disable_irqs = 0;
27module_param_named(disable_irqs, w1_disable_irqs, int, 0);
28
29static u8 w1_crc8_table[] = {
30 0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
31 157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
32 35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
33 190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
34 70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
35 219, 133, 103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
36 101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
37 248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
38 140, 210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113, 147, 205,
39 17, 79, 173, 243, 112, 46, 204, 146, 211, 141, 111, 49, 178, 236, 14, 80,
40 175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82, 176, 238,
41 50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
42 202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
43 87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
44 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168,
45 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53
46};
47
48static void w1_delay(unsigned long tm)
49{
50 udelay(tm * w1_delay_parm);
51}
52
53static void w1_write_bit(struct w1_master *dev, int bit);
54static u8 w1_read_bit(struct w1_master *dev);
55
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59
60
61u8 w1_touch_bit(struct w1_master *dev, int bit)
62{
63 if (dev->bus_master->touch_bit)
64 return dev->bus_master->touch_bit(dev->bus_master->data, bit);
65 else if (bit)
66 return w1_read_bit(dev);
67 else {
68 w1_write_bit(dev, 0);
69 return 0;
70 }
71}
72EXPORT_SYMBOL_GPL(w1_touch_bit);
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80
81static void w1_write_bit(struct w1_master *dev, int bit)
82{
83 unsigned long flags = 0;
84
85 if(w1_disable_irqs) local_irq_save(flags);
86
87 if (bit) {
88 dev->bus_master->write_bit(dev->bus_master->data, 0);
89 w1_delay(6);
90 dev->bus_master->write_bit(dev->bus_master->data, 1);
91 w1_delay(64);
92 } else {
93 dev->bus_master->write_bit(dev->bus_master->data, 0);
94 w1_delay(60);
95 dev->bus_master->write_bit(dev->bus_master->data, 1);
96 w1_delay(10);
97 }
98
99 if(w1_disable_irqs) local_irq_restore(flags);
100}
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109
110static void w1_pre_write(struct w1_master *dev)
111{
112 if (dev->pullup_duration &&
113 dev->enable_pullup && dev->bus_master->set_pullup) {
114 dev->bus_master->set_pullup(dev->bus_master->data,
115 dev->pullup_duration);
116 }
117}
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127static void w1_post_write(struct w1_master *dev)
128{
129 if (dev->pullup_duration) {
130 if (dev->enable_pullup && dev->bus_master->set_pullup)
131 dev->bus_master->set_pullup(dev->bus_master->data, 0);
132 else
133 msleep(dev->pullup_duration);
134 dev->pullup_duration = 0;
135 }
136}
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142
143void w1_write_8(struct w1_master *dev, u8 byte)
144{
145 int i;
146
147 if (dev->bus_master->write_byte) {
148 w1_pre_write(dev);
149 dev->bus_master->write_byte(dev->bus_master->data, byte);
150 }
151 else
152 for (i = 0; i < 8; ++i) {
153 if (i == 7)
154 w1_pre_write(dev);
155 w1_touch_bit(dev, (byte >> i) & 0x1);
156 }
157 w1_post_write(dev);
158}
159EXPORT_SYMBOL_GPL(w1_write_8);
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168static u8 w1_read_bit(struct w1_master *dev)
169{
170 int result;
171 unsigned long flags = 0;
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174 local_irq_save(flags);
175 dev->bus_master->write_bit(dev->bus_master->data, 0);
176 w1_delay(6);
177 dev->bus_master->write_bit(dev->bus_master->data, 1);
178 w1_delay(9);
179
180 result = dev->bus_master->read_bit(dev->bus_master->data);
181 local_irq_restore(flags);
182
183 w1_delay(55);
184
185 return result & 0x1;
186}
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201u8 w1_triplet(struct w1_master *dev, int bdir)
202{
203 if (dev->bus_master->triplet)
204 return dev->bus_master->triplet(dev->bus_master->data, bdir);
205 else {
206 u8 id_bit = w1_touch_bit(dev, 1);
207 u8 comp_bit = w1_touch_bit(dev, 1);
208 u8 retval;
209
210 if (id_bit && comp_bit)
211 return 0x03;
212
213 if (!id_bit && !comp_bit) {
214
215 retval = bdir ? 0x04 : 0;
216 } else {
217
218 bdir = id_bit;
219 retval = id_bit ? 0x05 : 0x02;
220 }
221
222 if (dev->bus_master->touch_bit)
223 w1_touch_bit(dev, bdir);
224 else
225 w1_write_bit(dev, bdir);
226 return retval;
227 }
228}
229EXPORT_SYMBOL_GPL(w1_triplet);
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237u8 w1_read_8(struct w1_master *dev)
238{
239 int i;
240 u8 res = 0;
241
242 if (dev->bus_master->read_byte)
243 res = dev->bus_master->read_byte(dev->bus_master->data);
244 else
245 for (i = 0; i < 8; ++i)
246 res |= (w1_touch_bit(dev,1) << i);
247
248 return res;
249}
250EXPORT_SYMBOL_GPL(w1_read_8);
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257
258void w1_write_block(struct w1_master *dev, const u8 *buf, int len)
259{
260 int i;
261
262 if (dev->bus_master->write_block) {
263 w1_pre_write(dev);
264 dev->bus_master->write_block(dev->bus_master->data, buf, len);
265 }
266 else
267 for (i = 0; i < len; ++i)
268 w1_write_8(dev, buf[i]);
269 w1_post_write(dev);
270}
271EXPORT_SYMBOL_GPL(w1_write_block);
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279void w1_touch_block(struct w1_master *dev, u8 *buf, int len)
280{
281 int i, j;
282 u8 tmp;
283
284 for (i = 0; i < len; ++i) {
285 tmp = 0;
286 for (j = 0; j < 8; ++j) {
287 if (j == 7)
288 w1_pre_write(dev);
289 tmp |= w1_touch_bit(dev, (buf[i] >> j) & 0x1) << j;
290 }
291
292 buf[i] = tmp;
293 }
294}
295EXPORT_SYMBOL_GPL(w1_touch_block);
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304u8 w1_read_block(struct w1_master *dev, u8 *buf, int len)
305{
306 int i;
307 u8 ret;
308
309 if (dev->bus_master->read_block)
310 ret = dev->bus_master->read_block(dev->bus_master->data, buf, len);
311 else {
312 for (i = 0; i < len; ++i)
313 buf[i] = w1_read_8(dev);
314 ret = len;
315 }
316
317 return ret;
318}
319EXPORT_SYMBOL_GPL(w1_read_block);
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325
326int w1_reset_bus(struct w1_master *dev)
327{
328 int result;
329 unsigned long flags = 0;
330
331 if(w1_disable_irqs) local_irq_save(flags);
332
333 if (dev->bus_master->reset_bus)
334 result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1;
335 else {
336 dev->bus_master->write_bit(dev->bus_master->data, 0);
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344 w1_delay(500);
345 dev->bus_master->write_bit(dev->bus_master->data, 1);
346 w1_delay(70);
347
348 result = dev->bus_master->read_bit(dev->bus_master->data) & 0x1;
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354 msleep(1);
355 }
356
357 if(w1_disable_irqs) local_irq_restore(flags);
358
359 return result;
360}
361EXPORT_SYMBOL_GPL(w1_reset_bus);
362
363u8 w1_calc_crc8(u8 * data, int len)
364{
365 u8 crc = 0;
366
367 while (len--)
368 crc = w1_crc8_table[crc ^ *data++];
369
370 return crc;
371}
372EXPORT_SYMBOL_GPL(w1_calc_crc8);
373
374void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
375{
376 dev->attempts++;
377 if (dev->bus_master->search)
378 dev->bus_master->search(dev->bus_master->data, dev,
379 search_type, cb);
380 else
381 w1_search(dev, search_type, cb);
382}
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395int w1_reset_select_slave(struct w1_slave *sl)
396{
397 if (w1_reset_bus(sl->master))
398 return -1;
399
400 if (sl->master->slave_count == 1)
401 w1_write_8(sl->master, W1_SKIP_ROM);
402 else {
403 u8 match[9] = {W1_MATCH_ROM, };
404 u64 rn = le64_to_cpu(*((u64*)&sl->reg_num));
405
406 memcpy(&match[1], &rn, 8);
407 w1_write_block(sl->master, match, 9);
408 }
409 return 0;
410}
411EXPORT_SYMBOL_GPL(w1_reset_select_slave);
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429int w1_reset_resume_command(struct w1_master *dev)
430{
431 if (w1_reset_bus(dev))
432 return -1;
433
434
435 w1_write_8(dev, W1_RESUME_CMD);
436 return 0;
437}
438EXPORT_SYMBOL_GPL(w1_reset_resume_command);
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454void w1_next_pullup(struct w1_master *dev, int delay)
455{
456 dev->pullup_duration = delay;
457}
458EXPORT_SYMBOL_GPL(w1_next_pullup);
459