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22#include <asm/types.h>
23
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/moduleparam.h>
27#include <linux/sched.h>
28#include <linux/device.h>
29#include <linux/types.h>
30#include <linux/slab.h>
31#include <linux/delay.h>
32
33#include "../w1.h"
34#include "../w1_int.h"
35#include "../w1_family.h"
36
37MODULE_LICENSE("GPL");
38MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
39MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family.");
40MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18S20));
41MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1822));
42MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18B20));
43MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1825));
44MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS28EA00));
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59static int w1_strong_pullup = 1;
60module_param_named(strong_pullup, w1_strong_pullup, int, 0);
61
62struct w1_therm_family_data {
63 uint8_t rom[9];
64 atomic_t refcnt;
65};
66
67
68#define THERM_REFCNT(family_data) \
69 (&((struct w1_therm_family_data*)family_data)->refcnt)
70
71static int w1_therm_add_slave(struct w1_slave *sl)
72{
73 sl->family_data = kzalloc(sizeof(struct w1_therm_family_data),
74 GFP_KERNEL);
75 if (!sl->family_data)
76 return -ENOMEM;
77 atomic_set(THERM_REFCNT(sl->family_data), 1);
78 return 0;
79}
80
81static void w1_therm_remove_slave(struct w1_slave *sl)
82{
83 int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data));
84 while(refcnt) {
85 msleep(1000);
86 refcnt = atomic_read(THERM_REFCNT(sl->family_data));
87 }
88 kfree(sl->family_data);
89 sl->family_data = NULL;
90}
91
92static ssize_t w1_slave_show(struct device *device,
93 struct device_attribute *attr, char *buf);
94
95static ssize_t w1_seq_show(struct device *device,
96 struct device_attribute *attr, char *buf);
97
98static DEVICE_ATTR_RO(w1_slave);
99static DEVICE_ATTR_RO(w1_seq);
100
101static struct attribute *w1_therm_attrs[] = {
102 &dev_attr_w1_slave.attr,
103 NULL,
104};
105
106static struct attribute *w1_ds28ea00_attrs[] = {
107 &dev_attr_w1_slave.attr,
108 &dev_attr_w1_seq.attr,
109 NULL,
110};
111ATTRIBUTE_GROUPS(w1_therm);
112ATTRIBUTE_GROUPS(w1_ds28ea00);
113
114static struct w1_family_ops w1_therm_fops = {
115 .add_slave = w1_therm_add_slave,
116 .remove_slave = w1_therm_remove_slave,
117 .groups = w1_therm_groups,
118};
119
120static struct w1_family_ops w1_ds28ea00_fops = {
121 .add_slave = w1_therm_add_slave,
122 .remove_slave = w1_therm_remove_slave,
123 .groups = w1_ds28ea00_groups,
124};
125
126static struct w1_family w1_therm_family_DS18S20 = {
127 .fid = W1_THERM_DS18S20,
128 .fops = &w1_therm_fops,
129};
130
131static struct w1_family w1_therm_family_DS18B20 = {
132 .fid = W1_THERM_DS18B20,
133 .fops = &w1_therm_fops,
134};
135
136static struct w1_family w1_therm_family_DS1822 = {
137 .fid = W1_THERM_DS1822,
138 .fops = &w1_therm_fops,
139};
140
141static struct w1_family w1_therm_family_DS28EA00 = {
142 .fid = W1_THERM_DS28EA00,
143 .fops = &w1_ds28ea00_fops,
144};
145
146static struct w1_family w1_therm_family_DS1825 = {
147 .fid = W1_THERM_DS1825,
148 .fops = &w1_therm_fops,
149};
150
151struct w1_therm_family_converter
152{
153 u8 broken;
154 u16 reserved;
155 struct w1_family *f;
156 int (*convert)(u8 rom[9]);
157};
158
159
160static inline int w1_DS18B20_convert_temp(u8 rom[9]);
161static inline int w1_DS18S20_convert_temp(u8 rom[9]);
162
163static struct w1_therm_family_converter w1_therm_families[] = {
164 {
165 .f = &w1_therm_family_DS18S20,
166 .convert = w1_DS18S20_convert_temp
167 },
168 {
169 .f = &w1_therm_family_DS1822,
170 .convert = w1_DS18B20_convert_temp
171 },
172 {
173 .f = &w1_therm_family_DS18B20,
174 .convert = w1_DS18B20_convert_temp
175 },
176 {
177 .f = &w1_therm_family_DS28EA00,
178 .convert = w1_DS18B20_convert_temp
179 },
180 {
181 .f = &w1_therm_family_DS1825,
182 .convert = w1_DS18B20_convert_temp
183 }
184};
185
186static inline int w1_DS18B20_convert_temp(u8 rom[9])
187{
188 s16 t = le16_to_cpup((__le16 *)rom);
189 return t*1000/16;
190}
191
192static inline int w1_DS18S20_convert_temp(u8 rom[9])
193{
194 int t, h;
195
196 if (!rom[7])
197 return 0;
198
199 if (rom[1] == 0)
200 t = ((s32)rom[0] >> 1)*1000;
201 else
202 t = 1000*(-1*(s32)(0x100-rom[0]) >> 1);
203
204 t -= 250;
205 h = 1000*((s32)rom[7] - (s32)rom[6]);
206 h /= (s32)rom[7];
207 t += h;
208
209 return t;
210}
211
212static inline int w1_convert_temp(u8 rom[9], u8 fid)
213{
214 int i;
215
216 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i)
217 if (w1_therm_families[i].f->fid == fid)
218 return w1_therm_families[i].convert(rom);
219
220 return 0;
221}
222
223
224static ssize_t w1_slave_show(struct device *device,
225 struct device_attribute *attr, char *buf)
226{
227 struct w1_slave *sl = dev_to_w1_slave(device);
228 struct w1_master *dev = sl->master;
229 u8 rom[9], crc, verdict, external_power;
230 int i, ret, max_trying = 10;
231 ssize_t c = PAGE_SIZE;
232 u8 *family_data = sl->family_data;
233
234 ret = mutex_lock_interruptible(&dev->bus_mutex);
235 if (ret != 0)
236 goto post_unlock;
237
238 if(!sl->family_data)
239 {
240 ret = -ENODEV;
241 goto pre_unlock;
242 }
243
244
245 atomic_inc(THERM_REFCNT(family_data));
246 memset(rom, 0, sizeof(rom));
247
248 while (max_trying--) {
249
250 verdict = 0;
251 crc = 0;
252
253 if (!w1_reset_select_slave(sl)) {
254 int count = 0;
255 unsigned int tm = 750;
256 unsigned long sleep_rem;
257
258 w1_write_8(dev, W1_READ_PSUPPLY);
259 external_power = w1_read_8(dev);
260
261 if (w1_reset_select_slave(sl))
262 continue;
263
264
265 if (w1_strong_pullup == 2 ||
266 (!external_power && w1_strong_pullup))
267 w1_next_pullup(dev, tm);
268
269 w1_write_8(dev, W1_CONVERT_TEMP);
270
271 if (external_power) {
272 mutex_unlock(&dev->bus_mutex);
273
274 sleep_rem = msleep_interruptible(tm);
275 if (sleep_rem != 0) {
276 ret = -EINTR;
277 goto post_unlock;
278 }
279
280 ret = mutex_lock_interruptible(&dev->bus_mutex);
281 if (ret != 0)
282 goto post_unlock;
283 } else if (!w1_strong_pullup) {
284 sleep_rem = msleep_interruptible(tm);
285 if (sleep_rem != 0) {
286 ret = -EINTR;
287 goto pre_unlock;
288 }
289 }
290
291 if (!w1_reset_select_slave(sl)) {
292
293 w1_write_8(dev, W1_READ_SCRATCHPAD);
294 if ((count = w1_read_block(dev, rom, 9)) != 9) {
295 dev_warn(device, "w1_read_block() "
296 "returned %u instead of 9.\n",
297 count);
298 }
299
300 crc = w1_calc_crc8(rom, 8);
301
302 if (rom[8] == crc)
303 verdict = 1;
304 }
305 }
306
307 if (verdict)
308 break;
309 }
310
311 for (i = 0; i < 9; ++i)
312 c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", rom[i]);
313 c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n",
314 crc, (verdict) ? "YES" : "NO");
315 if (verdict)
316 memcpy(family_data, rom, sizeof(rom));
317 else
318 dev_warn(device, "Read failed CRC check\n");
319
320 for (i = 0; i < 9; ++i)
321 c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ",
322 ((u8 *)family_data)[i]);
323
324 c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n",
325 w1_convert_temp(rom, sl->family->fid));
326 ret = PAGE_SIZE - c;
327
328pre_unlock:
329 mutex_unlock(&dev->bus_mutex);
330
331post_unlock:
332 atomic_dec(THERM_REFCNT(family_data));
333 return ret;
334}
335
336#define W1_42_CHAIN 0x99
337#define W1_42_CHAIN_OFF 0x3C
338#define W1_42_CHAIN_OFF_INV 0xC3
339#define W1_42_CHAIN_ON 0x5A
340#define W1_42_CHAIN_ON_INV 0xA5
341#define W1_42_CHAIN_DONE 0x96
342#define W1_42_CHAIN_DONE_INV 0x69
343#define W1_42_COND_READ 0x0F
344#define W1_42_SUCCESS_CONFIRM_BYTE 0xAA
345#define W1_42_FINISHED_BYTE 0xFF
346static ssize_t w1_seq_show(struct device *device,
347 struct device_attribute *attr, char *buf)
348{
349 struct w1_slave *sl = dev_to_w1_slave(device);
350 ssize_t c = PAGE_SIZE;
351 int rv;
352 int i;
353 u8 ack;
354 u64 rn;
355 struct w1_reg_num *reg_num;
356 int seq = 0;
357
358 mutex_lock(&sl->master->bus_mutex);
359
360 if (w1_reset_bus(sl->master))
361 goto error;
362 w1_write_8(sl->master, W1_SKIP_ROM);
363 w1_write_8(sl->master, W1_42_CHAIN);
364 w1_write_8(sl->master, W1_42_CHAIN_ON);
365 w1_write_8(sl->master, W1_42_CHAIN_ON_INV);
366 msleep(sl->master->pullup_duration);
367
368
369 ack = w1_read_8(sl->master);
370 if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
371 goto error;
372
373
374 for (i = 0; i <= 64; i++) {
375 if (w1_reset_bus(sl->master))
376 goto error;
377
378 w1_write_8(sl->master, W1_42_COND_READ);
379 rv = w1_read_block(sl->master, (u8 *)&rn, 8);
380 reg_num = (struct w1_reg_num *) &rn;
381 if (reg_num->family == W1_42_FINISHED_BYTE)
382 break;
383 if (sl->reg_num.id == reg_num->id)
384 seq = i;
385
386 w1_write_8(sl->master, W1_42_CHAIN);
387 w1_write_8(sl->master, W1_42_CHAIN_DONE);
388 w1_write_8(sl->master, W1_42_CHAIN_DONE_INV);
389 w1_read_block(sl->master, &ack, sizeof(ack));
390
391
392 ack = w1_read_8(sl->master);
393 if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
394 goto error;
395
396 }
397
398
399 if (w1_reset_bus(sl->master))
400 goto error;
401 w1_write_8(sl->master, W1_SKIP_ROM);
402 w1_write_8(sl->master, W1_42_CHAIN);
403 w1_write_8(sl->master, W1_42_CHAIN_OFF);
404 w1_write_8(sl->master, W1_42_CHAIN_OFF_INV);
405
406
407 ack = w1_read_8(sl->master);
408 if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
409 goto error;
410 mutex_unlock(&sl->master->bus_mutex);
411
412 c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", seq);
413 return PAGE_SIZE - c;
414error:
415 mutex_unlock(&sl->master->bus_mutex);
416 return -EIO;
417}
418
419static int __init w1_therm_init(void)
420{
421 int err, i;
422
423 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i) {
424 err = w1_register_family(w1_therm_families[i].f);
425 if (err)
426 w1_therm_families[i].broken = 1;
427 }
428
429 return 0;
430}
431
432static void __exit w1_therm_fini(void)
433{
434 int i;
435
436 for (i = 0; i < ARRAY_SIZE(w1_therm_families); ++i)
437 if (!w1_therm_families[i].broken)
438 w1_unregister_family(w1_therm_families[i].f);
439}
440
441module_init(w1_therm_init);
442module_exit(w1_therm_fini);
443
