1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
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
65
66
67static u8 w1_touch_bit(struct w1_master *dev, int bit)
68{
69 if (dev->bus_master->touch_bit)
70 return dev->bus_master->touch_bit(dev->bus_master->data, bit);
71 else if (bit)
72 return w1_read_bit(dev);
73 else {
74 w1_write_bit(dev, 0);
75 return 0;
76 }
77}
78
79
80
81
82
83static void w1_write_bit(struct w1_master *dev, int bit)
84{
85 unsigned long flags = 0;
86
87 if(w1_disable_irqs) local_irq_save(flags);
88
89 if (bit) {
90 dev->bus_master->write_bit(dev->bus_master->data, 0);
91 w1_delay(6);
92 dev->bus_master->write_bit(dev->bus_master->data, 1);
93 w1_delay(64);
94 } else {
95 dev->bus_master->write_bit(dev->bus_master->data, 0);
96 w1_delay(60);
97 dev->bus_master->write_bit(dev->bus_master->data, 1);
98 w1_delay(10);
99 }
100
101 if(w1_disable_irqs) local_irq_restore(flags);
102}
103
104
105
106
107
108
109
110
111static void w1_pre_write(struct w1_master *dev)
112{
113 if (dev->pullup_duration &&
114 dev->enable_pullup && dev->bus_master->set_pullup) {
115 dev->bus_master->set_pullup(dev->bus_master->data,
116 dev->pullup_duration);
117 }
118}
119
120
121
122
123
124
125
126
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}
137
138
139
140
141
142
143
144void w1_write_8(struct w1_master *dev, u8 byte)
145{
146 int i;
147
148 if (dev->bus_master->write_byte) {
149 w1_pre_write(dev);
150 dev->bus_master->write_byte(dev->bus_master->data, byte);
151 }
152 else
153 for (i = 0; i < 8; ++i) {
154 if (i == 7)
155 w1_pre_write(dev);
156 w1_touch_bit(dev, (byte >> i) & 0x1);
157 }
158 w1_post_write(dev);
159}
160EXPORT_SYMBOL_GPL(w1_write_8);
161
162
163
164
165
166
167static u8 w1_read_bit(struct w1_master *dev)
168{
169 int result;
170 unsigned long flags = 0;
171
172
173 local_irq_save(flags);
174 dev->bus_master->write_bit(dev->bus_master->data, 0);
175 w1_delay(6);
176 dev->bus_master->write_bit(dev->bus_master->data, 1);
177 w1_delay(9);
178
179 result = dev->bus_master->read_bit(dev->bus_master->data);
180 local_irq_restore(flags);
181
182 w1_delay(55);
183
184 return result & 0x1;
185}
186
187
188
189
190
191
192
193
194
195
196
197
198
199u8 w1_triplet(struct w1_master *dev, int bdir)
200{
201 if (dev->bus_master->triplet)
202 return dev->bus_master->triplet(dev->bus_master->data, bdir);
203 else {
204 u8 id_bit = w1_touch_bit(dev, 1);
205 u8 comp_bit = w1_touch_bit(dev, 1);
206 u8 retval;
207
208 if (id_bit && comp_bit)
209 return 0x03;
210
211 if (!id_bit && !comp_bit) {
212
213 retval = bdir ? 0x04 : 0;
214 } else {
215
216 bdir = id_bit;
217 retval = id_bit ? 0x05 : 0x02;
218 }
219
220 if (dev->bus_master->touch_bit)
221 w1_touch_bit(dev, bdir);
222 else
223 w1_write_bit(dev, bdir);
224 return retval;
225 }
226}
227
228
229
230
231
232
233
234u8 w1_read_8(struct w1_master *dev)
235{
236 int i;
237 u8 res = 0;
238
239 if (dev->bus_master->read_byte)
240 res = dev->bus_master->read_byte(dev->bus_master->data);
241 else
242 for (i = 0; i < 8; ++i)
243 res |= (w1_touch_bit(dev,1) << i);
244
245 return res;
246}
247EXPORT_SYMBOL_GPL(w1_read_8);
248
249
250
251
252
253
254
255
256void w1_write_block(struct w1_master *dev, const u8 *buf, int len)
257{
258 int i;
259
260 if (dev->bus_master->write_block) {
261 w1_pre_write(dev);
262 dev->bus_master->write_block(dev->bus_master->data, buf, len);
263 }
264 else
265 for (i = 0; i < len; ++i)
266 w1_write_8(dev, buf[i]);
267 w1_post_write(dev);
268}
269EXPORT_SYMBOL_GPL(w1_write_block);
270
271
272
273
274
275
276
277
278void w1_touch_block(struct w1_master *dev, u8 *buf, int len)
279{
280 int i, j;
281 u8 tmp;
282
283 for (i = 0; i < len; ++i) {
284 tmp = 0;
285 for (j = 0; j < 8; ++j) {
286 if (j == 7)
287 w1_pre_write(dev);
288 tmp |= w1_touch_bit(dev, (buf[i] >> j) & 0x1) << j;
289 }
290
291 buf[i] = tmp;
292 }
293}
294EXPORT_SYMBOL_GPL(w1_touch_block);
295
296
297
298
299
300
301
302
303
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);
320
321
322
323
324
325
326
327int w1_reset_bus(struct w1_master *dev)
328{
329 int result;
330 unsigned long flags = 0;
331
332 if(w1_disable_irqs) local_irq_save(flags);
333
334 if (dev->bus_master->reset_bus)
335 result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1;
336 else {
337 dev->bus_master->write_bit(dev->bus_master->data, 0);
338
339
340
341
342
343
344
345 w1_delay(500);
346 dev->bus_master->write_bit(dev->bus_master->data, 1);
347 w1_delay(70);
348
349 result = dev->bus_master->read_bit(dev->bus_master->data) & 0x1;
350
351
352
353
354
355 msleep(1);
356 }
357
358 if(w1_disable_irqs) local_irq_restore(flags);
359
360 return result;
361}
362EXPORT_SYMBOL_GPL(w1_reset_bus);
363
364u8 w1_calc_crc8(u8 * data, int len)
365{
366 u8 crc = 0;
367
368 while (len--)
369 crc = w1_crc8_table[crc ^ *data++];
370
371 return crc;
372}
373EXPORT_SYMBOL_GPL(w1_calc_crc8);
374
375void w1_search_devices(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
376{
377 dev->attempts++;
378 if (dev->bus_master->search)
379 dev->bus_master->search(dev->bus_master->data, dev,
380 search_type, cb);
381 else
382 w1_search(dev, search_type, cb);
383}
384
385
386
387
388
389
390
391
392
393int w1_reset_select_slave(struct w1_slave *sl)
394{
395 if (w1_reset_bus(sl->master))
396 return -1;
397
398 if (sl->master->slave_count == 1)
399 w1_write_8(sl->master, W1_SKIP_ROM);
400 else {
401 u8 match[9] = {W1_MATCH_ROM, };
402 u64 rn = le64_to_cpu(*((u64*)&sl->reg_num));
403
404 memcpy(&match[1], &rn, 8);
405 w1_write_block(sl->master, match, 9);
406 }
407 return 0;
408}
409EXPORT_SYMBOL_GPL(w1_reset_select_slave);
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426int w1_reset_resume_command(struct w1_master *dev)
427{
428 if (w1_reset_bus(dev))
429 return -1;
430
431
432 w1_write_8(dev, W1_RESUME_CMD);
433 return 0;
434}
435EXPORT_SYMBOL_GPL(w1_reset_resume_command);
436
437
438
439
440
441
442
443
444
445
446
447
448void w1_next_pullup(struct w1_master *dev, int delay)
449{
450 dev->pullup_duration = delay;
451}
452EXPORT_SYMBOL_GPL(w1_next_pullup);
453