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22#include <asm/io.h>
23
24#include <linux/delay.h>
25#include <linux/moduleparam.h>
26#include <linux/module.h>
27
28#include "w1.h"
29#include "w1_log.h"
30
31static int w1_delay_parm = 1;
32module_param_named(delay_coef, w1_delay_parm, int, 0);
33
34static int w1_disable_irqs = 0;
35module_param_named(disable_irqs, w1_disable_irqs, int, 0);
36
37static u8 w1_crc8_table[] = {
38 0, 94, 188, 226, 97, 63, 221, 131, 194, 156, 126, 32, 163, 253, 31, 65,
39 157, 195, 33, 127, 252, 162, 64, 30, 95, 1, 227, 189, 62, 96, 130, 220,
40 35, 125, 159, 193, 66, 28, 254, 160, 225, 191, 93, 3, 128, 222, 60, 98,
41 190, 224, 2, 92, 223, 129, 99, 61, 124, 34, 192, 158, 29, 67, 161, 255,
42 70, 24, 250, 164, 39, 121, 155, 197, 132, 218, 56, 102, 229, 187, 89, 7,
43 219, 133, 103, 57, 186, 228, 6, 88, 25, 71, 165, 251, 120, 38, 196, 154,
44 101, 59, 217, 135, 4, 90, 184, 230, 167, 249, 27, 69, 198, 152, 122, 36,
45 248, 166, 68, 26, 153, 199, 37, 123, 58, 100, 134, 216, 91, 5, 231, 185,
46 140, 210, 48, 110, 237, 179, 81, 15, 78, 16, 242, 172, 47, 113, 147, 205,
47 17, 79, 173, 243, 112, 46, 204, 146, 211, 141, 111, 49, 178, 236, 14, 80,
48 175, 241, 19, 77, 206, 144, 114, 44, 109, 51, 209, 143, 12, 82, 176, 238,
49 50, 108, 142, 208, 83, 13, 239, 177, 240, 174, 76, 18, 145, 207, 45, 115,
50 202, 148, 118, 40, 171, 245, 23, 73, 8, 86, 180, 234, 105, 55, 213, 139,
51 87, 9, 235, 181, 54, 104, 138, 212, 149, 203, 41, 119, 244, 170, 72, 22,
52 233, 183, 85, 11, 136, 214, 52, 106, 43, 117, 151, 201, 74, 20, 246, 168,
53 116, 42, 200, 150, 21, 75, 169, 247, 182, 232, 10, 84, 215, 137, 107, 53
54};
55
56static void w1_delay(unsigned long tm)
57{
58 udelay(tm * w1_delay_parm);
59}
60
61static void w1_write_bit(struct w1_master *dev, int bit);
62static u8 w1_read_bit(struct w1_master *dev);
63
64
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66
67
68
69static u8 w1_touch_bit(struct w1_master *dev, int bit)
70{
71 if (dev->bus_master->touch_bit)
72 return dev->bus_master->touch_bit(dev->bus_master->data, bit);
73 else if (bit)
74 return w1_read_bit(dev);
75 else {
76 w1_write_bit(dev, 0);
77 return 0;
78 }
79}
80
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87
88static void w1_write_bit(struct w1_master *dev, int bit)
89{
90 unsigned long flags = 0;
91
92 if(w1_disable_irqs) local_irq_save(flags);
93
94 if (bit) {
95 dev->bus_master->write_bit(dev->bus_master->data, 0);
96 w1_delay(6);
97 dev->bus_master->write_bit(dev->bus_master->data, 1);
98 w1_delay(64);
99 } else {
100 dev->bus_master->write_bit(dev->bus_master->data, 0);
101 w1_delay(60);
102 dev->bus_master->write_bit(dev->bus_master->data, 1);
103 w1_delay(10);
104 }
105
106 if(w1_disable_irqs) local_irq_restore(flags);
107}
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116
117static void w1_pre_write(struct w1_master *dev)
118{
119 if (dev->pullup_duration &&
120 dev->enable_pullup && dev->bus_master->set_pullup) {
121 dev->bus_master->set_pullup(dev->bus_master->data,
122 dev->pullup_duration);
123 }
124}
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133
134static void w1_post_write(struct w1_master *dev)
135{
136 if (dev->pullup_duration) {
137 if (dev->enable_pullup && dev->bus_master->set_pullup)
138 dev->bus_master->set_pullup(dev->bus_master->data, 0);
139 else
140 msleep(dev->pullup_duration);
141 dev->pullup_duration = 0;
142 }
143}
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149
150void w1_write_8(struct w1_master *dev, u8 byte)
151{
152 int i;
153
154 if (dev->bus_master->write_byte) {
155 w1_pre_write(dev);
156 dev->bus_master->write_byte(dev->bus_master->data, byte);
157 }
158 else
159 for (i = 0; i < 8; ++i) {
160 if (i == 7)
161 w1_pre_write(dev);
162 w1_touch_bit(dev, (byte >> i) & 0x1);
163 }
164 w1_post_write(dev);
165}
166EXPORT_SYMBOL_GPL(w1_write_8);
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174
175static u8 w1_read_bit(struct w1_master *dev)
176{
177 int result;
178 unsigned long flags = 0;
179
180
181 local_irq_save(flags);
182 dev->bus_master->write_bit(dev->bus_master->data, 0);
183 w1_delay(6);
184 dev->bus_master->write_bit(dev->bus_master->data, 1);
185 w1_delay(9);
186
187 result = dev->bus_master->read_bit(dev->bus_master->data);
188 local_irq_restore(flags);
189
190 w1_delay(55);
191
192 return result & 0x1;
193}
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208u8 w1_triplet(struct w1_master *dev, int bdir)
209{
210 if (dev->bus_master->triplet)
211 return dev->bus_master->triplet(dev->bus_master->data, bdir);
212 else {
213 u8 id_bit = w1_touch_bit(dev, 1);
214 u8 comp_bit = w1_touch_bit(dev, 1);
215 u8 retval;
216
217 if (id_bit && comp_bit)
218 return 0x03;
219
220 if (!id_bit && !comp_bit) {
221
222 retval = bdir ? 0x04 : 0;
223 } else {
224
225 bdir = id_bit;
226 retval = id_bit ? 0x05 : 0x02;
227 }
228
229 if (dev->bus_master->touch_bit)
230 w1_touch_bit(dev, bdir);
231 else
232 w1_write_bit(dev, bdir);
233 return retval;
234 }
235}
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243u8 w1_read_8(struct w1_master *dev)
244{
245 int i;
246 u8 res = 0;
247
248 if (dev->bus_master->read_byte)
249 res = dev->bus_master->read_byte(dev->bus_master->data);
250 else
251 for (i = 0; i < 8; ++i)
252 res |= (w1_touch_bit(dev,1) << i);
253
254 return res;
255}
256EXPORT_SYMBOL_GPL(w1_read_8);
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263
264void w1_write_block(struct w1_master *dev, const u8 *buf, int len)
265{
266 int i;
267
268 if (dev->bus_master->write_block) {
269 w1_pre_write(dev);
270 dev->bus_master->write_block(dev->bus_master->data, buf, len);
271 }
272 else
273 for (i = 0; i < len; ++i)
274 w1_write_8(dev, buf[i]);
275 w1_post_write(dev);
276}
277EXPORT_SYMBOL_GPL(w1_write_block);
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284
285void w1_touch_block(struct w1_master *dev, u8 *buf, int len)
286{
287 int i, j;
288 u8 tmp;
289
290 for (i = 0; i < len; ++i) {
291 tmp = 0;
292 for (j = 0; j < 8; ++j) {
293 if (j == 7)
294 w1_pre_write(dev);
295 tmp |= w1_touch_bit(dev, (buf[i] >> j) & 0x1) << j;
296 }
297
298 buf[i] = tmp;
299 }
300}
301EXPORT_SYMBOL_GPL(w1_touch_block);
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310u8 w1_read_block(struct w1_master *dev, u8 *buf, int len)
311{
312 int i;
313 u8 ret;
314
315 if (dev->bus_master->read_block)
316 ret = dev->bus_master->read_block(dev->bus_master->data, buf, len);
317 else {
318 for (i = 0; i < len; ++i)
319 buf[i] = w1_read_8(dev);
320 ret = len;
321 }
322
323 return ret;
324}
325EXPORT_SYMBOL_GPL(w1_read_block);
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331
332int w1_reset_bus(struct w1_master *dev)
333{
334 int result;
335 unsigned long flags = 0;
336
337 if(w1_disable_irqs) local_irq_save(flags);
338
339 if (dev->bus_master->reset_bus)
340 result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1;
341 else {
342 dev->bus_master->write_bit(dev->bus_master->data, 0);
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350 w1_delay(500);
351 dev->bus_master->write_bit(dev->bus_master->data, 1);
352 w1_delay(70);
353
354 result = dev->bus_master->read_bit(dev->bus_master->data) & 0x1;
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359
360 msleep(1);
361 }
362
363 if(w1_disable_irqs) local_irq_restore(flags);
364
365 return result;
366}
367EXPORT_SYMBOL_GPL(w1_reset_bus);
368
369u8 w1_calc_crc8(u8 * data, int len)
370{
371 u8 crc = 0;
372
373 while (len--)
374 crc = w1_crc8_table[crc ^ *data++];
375
376 return crc;
377}
378EXPORT_SYMBOL_GPL(w1_calc_crc8);
379
380void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
381{
382 dev->attempts++;
383 if (dev->bus_master->search)
384 dev->bus_master->search(dev->bus_master->data, dev,
385 search_type, cb);
386 else
387 w1_search(dev, search_type, cb);
388}
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401int w1_reset_select_slave(struct w1_slave *sl)
402{
403 if (w1_reset_bus(sl->master))
404 return -1;
405
406 if (sl->master->slave_count == 1)
407 w1_write_8(sl->master, W1_SKIP_ROM);
408 else {
409 u8 match[9] = {W1_MATCH_ROM, };
410 u64 rn = le64_to_cpu(*((u64*)&sl->reg_num));
411
412 memcpy(&match[1], &rn, 8);
413 w1_write_block(sl->master, match, 9);
414 }
415 return 0;
416}
417EXPORT_SYMBOL_GPL(w1_reset_select_slave);
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435int w1_reset_resume_command(struct w1_master *dev)
436{
437 if (w1_reset_bus(dev))
438 return -1;
439
440
441 w1_write_8(dev, W1_RESUME_CMD);
442 return 0;
443}
444EXPORT_SYMBOL_GPL(w1_reset_resume_command);
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460void w1_next_pullup(struct w1_master *dev, int delay)
461{
462 dev->pullup_duration = delay;
463}
464EXPORT_SYMBOL_GPL(w1_next_pullup);
465