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21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/slab.h>
24#include <linux/init.h>
25#include <linux/bcd.h>
26#include <linux/i2c.h>
27#include <linux/list.h>
28#include <linux/rtc.h>
29
30
31#define RX8025_REG_SEC 0x00
32#define RX8025_REG_MIN 0x01
33#define RX8025_REG_HOUR 0x02
34#define RX8025_REG_WDAY 0x03
35#define RX8025_REG_MDAY 0x04
36#define RX8025_REG_MONTH 0x05
37#define RX8025_REG_YEAR 0x06
38#define RX8025_REG_DIGOFF 0x07
39#define RX8025_REG_ALWMIN 0x08
40#define RX8025_REG_ALWHOUR 0x09
41#define RX8025_REG_ALWWDAY 0x0a
42#define RX8025_REG_ALDMIN 0x0b
43#define RX8025_REG_ALDHOUR 0x0c
44
45#define RX8025_REG_CTRL1 0x0e
46#define RX8025_REG_CTRL2 0x0f
47
48#define RX8025_BIT_CTRL1_CT (7 << 0)
49
50#define RX8025_BIT_CTRL1_CT_1HZ 4
51#define RX8025_BIT_CTRL1_TEST (1 << 3)
52#define RX8025_BIT_CTRL1_1224 (1 << 5)
53#define RX8025_BIT_CTRL1_DALE (1 << 6)
54#define RX8025_BIT_CTRL1_WALE (1 << 7)
55
56#define RX8025_BIT_CTRL2_DAFG (1 << 0)
57#define RX8025_BIT_CTRL2_WAFG (1 << 1)
58#define RX8025_BIT_CTRL2_CTFG (1 << 2)
59#define RX8025_BIT_CTRL2_PON (1 << 4)
60#define RX8025_BIT_CTRL2_XST (1 << 5)
61#define RX8025_BIT_CTRL2_VDET (1 << 6)
62
63
64#define RX8025_ADJ_RESOLUTION 3050
65#define RX8025_ADJ_DATA_MAX 62
66#define RX8025_ADJ_DATA_MIN -62
67
68static const struct i2c_device_id rx8025_id[] = {
69 { "rx8025", 0 },
70 { }
71};
72MODULE_DEVICE_TABLE(i2c, rx8025_id);
73
74struct rx8025_data {
75 struct i2c_client *client;
76 struct rtc_device *rtc;
77 struct work_struct work;
78 u8 ctrl1;
79 unsigned exiting:1;
80};
81
82static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
83{
84 int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
85
86 if (ret < 0) {
87 dev_err(&client->dev, "Unable to read register #%d\n", number);
88 return ret;
89 }
90
91 *value = ret;
92 return 0;
93}
94
95static int rx8025_read_regs(struct i2c_client *client,
96 int number, u8 length, u8 *values)
97{
98 int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
99 length, values);
100
101 if (ret != length) {
102 dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
103 number, number + length - 1);
104 return ret < 0 ? ret : -EIO;
105 }
106
107 return 0;
108}
109
110static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
111{
112 int ret = i2c_smbus_write_byte_data(client, number << 4, value);
113
114 if (ret)
115 dev_err(&client->dev, "Unable to write register #%d\n",
116 number);
117
118 return ret;
119}
120
121static int rx8025_write_regs(struct i2c_client *client,
122 int number, u8 length, u8 *values)
123{
124 int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
125 length, values);
126
127 if (ret)
128 dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
129 number, number + length - 1);
130
131 return ret;
132}
133
134static irqreturn_t rx8025_irq(int irq, void *dev_id)
135{
136 struct i2c_client *client = dev_id;
137 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
138
139 disable_irq_nosync(irq);
140 schedule_work(&rx8025->work);
141 return IRQ_HANDLED;
142}
143
144static void rx8025_work(struct work_struct *work)
145{
146 struct rx8025_data *rx8025 = container_of(work, struct rx8025_data,
147 work);
148 struct i2c_client *client = rx8025->client;
149 struct mutex *lock = &rx8025->rtc->ops_lock;
150 u8 status;
151
152 mutex_lock(lock);
153
154 if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
155 goto out;
156
157 if (!(status & RX8025_BIT_CTRL2_XST))
158 dev_warn(&client->dev, "Oscillation stop was detected,"
159 "you may have to readjust the clock\n");
160
161 if (status & RX8025_BIT_CTRL2_CTFG) {
162
163 status &= ~RX8025_BIT_CTRL2_CTFG;
164 local_irq_disable();
165 rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
166 local_irq_enable();
167 }
168
169 if (status & RX8025_BIT_CTRL2_DAFG) {
170
171 status &= RX8025_BIT_CTRL2_DAFG;
172 if (rx8025_write_reg(client, RX8025_REG_CTRL1,
173 rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
174 goto out;
175 local_irq_disable();
176 rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
177 local_irq_enable();
178 }
179
180
181 rx8025_write_reg(client, RX8025_REG_CTRL2,
182 status | RX8025_BIT_CTRL2_XST);
183
184out:
185 if (!rx8025->exiting)
186 enable_irq(client->irq);
187
188 mutex_unlock(lock);
189}
190
191static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
192{
193 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
194 u8 date[7];
195 int err;
196
197 err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
198 if (err)
199 return err;
200
201 dev_dbg(dev, "%s: read 0x%02x 0x%02x "
202 "0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
203 date[0], date[1], date[2], date[3], date[4],
204 date[5], date[6]);
205
206 dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
207 dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
208 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
209 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
210 else
211 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
212 + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
213
214 dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
215 dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
216 dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
217
218 if (dt->tm_year < 70)
219 dt->tm_year += 100;
220
221 dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
222 dt->tm_sec, dt->tm_min, dt->tm_hour,
223 dt->tm_mday, dt->tm_mon, dt->tm_year);
224
225 return rtc_valid_tm(dt);
226}
227
228static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
229{
230 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
231 u8 date[7];
232
233
234
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237
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239
240
241
242
243 date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
244 date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
245 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
246 date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
247 else
248 date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
249 | bin2bcd((dt->tm_hour + 11) % 12 + 1);
250
251 date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
252 date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
253 date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
254 date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
255
256 dev_dbg(dev,
257 "%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
258 __func__,
259 date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
260
261 return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
262}
263
264static int rx8025_init_client(struct i2c_client *client, int *need_reset)
265{
266 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
267 u8 ctrl[2], ctrl2;
268 int need_clear = 0;
269 int err;
270
271 err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
272 if (err)
273 goto out;
274
275
276 rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
277
278 if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
279 dev_warn(&client->dev, "power-on reset was detected, "
280 "you may have to readjust the clock\n");
281 *need_reset = 1;
282 }
283
284 if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
285 dev_warn(&client->dev, "a power voltage drop was detected, "
286 "you may have to readjust the clock\n");
287 *need_reset = 1;
288 }
289
290 if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
291 dev_warn(&client->dev, "Oscillation stop was detected,"
292 "you may have to readjust the clock\n");
293 *need_reset = 1;
294 }
295
296 if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
297 dev_warn(&client->dev, "Alarm was detected\n");
298 need_clear = 1;
299 }
300
301 if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
302 need_clear = 1;
303
304 if (*need_reset || need_clear) {
305 ctrl2 = ctrl[0];
306 ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
307 RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
308 RX8025_BIT_CTRL2_DAFG);
309 ctrl2 |= RX8025_BIT_CTRL2_XST;
310
311 err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
312 }
313out:
314 return err;
315}
316
317
318static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
319{
320 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
321 struct i2c_client *client = rx8025->client;
322 u8 ctrl2, ald[2];
323 int err;
324
325 if (client->irq <= 0)
326 return -EINVAL;
327
328 err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
329 if (err)
330 return err;
331
332 err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
333 if (err)
334 return err;
335
336 dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
337 __func__, ald[0], ald[1], ctrl2);
338
339
340 t->time.tm_sec = 0;
341 t->time.tm_min = bcd2bin(ald[0] & 0x7f);
342 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
343 t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
344 else
345 t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
346 + (ald[1] & 0x20 ? 12 : 0);
347
348 t->time.tm_wday = -1;
349 t->time.tm_mday = -1;
350 t->time.tm_mon = -1;
351 t->time.tm_year = -1;
352
353 dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
354 __func__,
355 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
356 t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
357 t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
358 t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
359
360 return err;
361}
362
363static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
364{
365 struct i2c_client *client = to_i2c_client(dev);
366 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
367 u8 ald[2];
368 int err;
369
370 if (client->irq <= 0)
371 return -EINVAL;
372
373
374 ald[0] = bin2bcd(t->time.tm_min);
375 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
376 ald[1] = bin2bcd(t->time.tm_hour);
377 else
378 ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
379 | bin2bcd((t->time.tm_hour + 11) % 12 + 1);
380
381 dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
382
383 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
384 rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
385 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
386 rx8025->ctrl1);
387 if (err)
388 return err;
389 }
390 err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
391 if (err)
392 return err;
393
394 if (t->enabled) {
395 rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
396 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
397 rx8025->ctrl1);
398 if (err)
399 return err;
400 }
401
402 return 0;
403}
404
405static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
406{
407 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
408 u8 ctrl1;
409 int err;
410
411 ctrl1 = rx8025->ctrl1;
412 if (enabled)
413 ctrl1 |= RX8025_BIT_CTRL1_DALE;
414 else
415 ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
416
417 if (ctrl1 != rx8025->ctrl1) {
418 rx8025->ctrl1 = ctrl1;
419 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
420 rx8025->ctrl1);
421 if (err)
422 return err;
423 }
424 return 0;
425}
426
427static struct rtc_class_ops rx8025_rtc_ops = {
428 .read_time = rx8025_get_time,
429 .set_time = rx8025_set_time,
430 .read_alarm = rx8025_read_alarm,
431 .set_alarm = rx8025_set_alarm,
432 .alarm_irq_enable = rx8025_alarm_irq_enable,
433};
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451
452static int rx8025_get_clock_adjust(struct device *dev, int *adj)
453{
454 struct i2c_client *client = to_i2c_client(dev);
455 u8 digoff;
456 int err;
457
458 err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
459 if (err)
460 return err;
461
462 *adj = digoff >= 64 ? digoff - 128 : digoff;
463 if (*adj > 0)
464 (*adj)--;
465 *adj *= -RX8025_ADJ_RESOLUTION;
466
467 return 0;
468}
469
470static int rx8025_set_clock_adjust(struct device *dev, int adj)
471{
472 struct i2c_client *client = to_i2c_client(dev);
473 u8 digoff;
474 int err;
475
476 adj /= -RX8025_ADJ_RESOLUTION;
477 if (adj > RX8025_ADJ_DATA_MAX)
478 adj = RX8025_ADJ_DATA_MAX;
479 else if (adj < RX8025_ADJ_DATA_MIN)
480 adj = RX8025_ADJ_DATA_MIN;
481 else if (adj > 0)
482 adj++;
483 else if (adj < 0)
484 adj += 128;
485 digoff = adj;
486
487 err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
488 if (err)
489 return err;
490
491 dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
492
493 return 0;
494}
495
496static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
497 struct device_attribute *attr,
498 char *buf)
499{
500 int err, adj;
501
502 err = rx8025_get_clock_adjust(dev, &adj);
503 if (err)
504 return err;
505
506 return sprintf(buf, "%d\n", adj);
507}
508
509static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
510 struct device_attribute *attr,
511 const char *buf, size_t count)
512{
513 int adj, err;
514
515 if (sscanf(buf, "%i", &adj) != 1)
516 return -EINVAL;
517
518 err = rx8025_set_clock_adjust(dev, adj);
519
520 return err ? err : count;
521}
522
523static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
524 rx8025_sysfs_show_clock_adjust,
525 rx8025_sysfs_store_clock_adjust);
526
527static int rx8025_sysfs_register(struct device *dev)
528{
529 return device_create_file(dev, &dev_attr_clock_adjust_ppb);
530}
531
532static void rx8025_sysfs_unregister(struct device *dev)
533{
534 device_remove_file(dev, &dev_attr_clock_adjust_ppb);
535}
536
537static int rx8025_probe(struct i2c_client *client,
538 const struct i2c_device_id *id)
539{
540 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
541 struct rx8025_data *rx8025;
542 int err, need_reset = 0;
543
544 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
545 | I2C_FUNC_SMBUS_I2C_BLOCK)) {
546 dev_err(&adapter->dev,
547 "doesn't support required functionality\n");
548 err = -EIO;
549 goto errout;
550 }
551
552 rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL);
553 if (!rx8025) {
554 err = -ENOMEM;
555 goto errout;
556 }
557
558 rx8025->client = client;
559 i2c_set_clientdata(client, rx8025);
560 INIT_WORK(&rx8025->work, rx8025_work);
561
562 err = rx8025_init_client(client, &need_reset);
563 if (err)
564 goto errout;
565
566 if (need_reset) {
567 struct rtc_time tm;
568 dev_info(&client->dev,
569 "bad conditions detected, resetting date\n");
570 rtc_time_to_tm(0, &tm);
571 rx8025_set_time(&client->dev, &tm);
572 }
573
574 rx8025->rtc = devm_rtc_device_register(&client->dev, client->name,
575 &rx8025_rtc_ops, THIS_MODULE);
576 if (IS_ERR(rx8025->rtc)) {
577 err = PTR_ERR(rx8025->rtc);
578 dev_err(&client->dev, "unable to register the class device\n");
579 goto errout;
580 }
581
582 if (client->irq > 0) {
583 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
584 err = request_irq(client->irq, rx8025_irq,
585 0, "rx8025", client);
586 if (err) {
587 dev_err(&client->dev, "unable to request IRQ\n");
588 goto errout;
589 }
590 }
591
592 rx8025->rtc->irq_freq = 1;
593 rx8025->rtc->max_user_freq = 1;
594
595 err = rx8025_sysfs_register(&client->dev);
596 if (err)
597 goto errout_irq;
598
599 return 0;
600
601errout_irq:
602 if (client->irq > 0)
603 free_irq(client->irq, client);
604
605errout:
606 dev_err(&adapter->dev, "probing for rx8025 failed\n");
607 return err;
608}
609
610static int rx8025_remove(struct i2c_client *client)
611{
612 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
613 struct mutex *lock = &rx8025->rtc->ops_lock;
614
615 if (client->irq > 0) {
616 mutex_lock(lock);
617 rx8025->exiting = 1;
618 mutex_unlock(lock);
619
620 free_irq(client->irq, client);
621 cancel_work_sync(&rx8025->work);
622 }
623
624 rx8025_sysfs_unregister(&client->dev);
625 return 0;
626}
627
628static struct i2c_driver rx8025_driver = {
629 .driver = {
630 .name = "rtc-rx8025",
631 .owner = THIS_MODULE,
632 },
633 .probe = rx8025_probe,
634 .remove = rx8025_remove,
635 .id_table = rx8025_id,
636};
637
638module_i2c_driver(rx8025_driver);
639
640MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
641MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
642MODULE_LICENSE("GPL");
643
