1 /*
2 * Micro Crystal RV-3029 / RV-3049 rtc class driver
3 *
4 * Author: Gregory Hermant <gregory.hermant@calao-systems.com>
5 * Michael Buesch <m@bues.ch>
6 *
7 * based on previously existing rtc class drivers
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12 *
13 */
14
15 #include <linux/module.h>
16 #include <linux/i2c.h>
17 #include <linux/spi/spi.h>
18 #include <linux/bcd.h>
19 #include <linux/rtc.h>
20 #include <linux/delay.h>
21 #include <linux/of.h>
22 #include <linux/hwmon.h>
23 #include <linux/hwmon-sysfs.h>
24 #include <linux/regmap.h>
25
26 /* Register map */
27 /* control section */
28 #define RV3029_ONOFF_CTRL 0x00
29 #define RV3029_ONOFF_CTRL_WE BIT(0)
30 #define RV3029_ONOFF_CTRL_TE BIT(1)
31 #define RV3029_ONOFF_CTRL_TAR BIT(2)
32 #define RV3029_ONOFF_CTRL_EERE BIT(3)
33 #define RV3029_ONOFF_CTRL_SRON BIT(4)
34 #define RV3029_ONOFF_CTRL_TD0 BIT(5)
35 #define RV3029_ONOFF_CTRL_TD1 BIT(6)
36 #define RV3029_ONOFF_CTRL_CLKINT BIT(7)
37 #define RV3029_IRQ_CTRL 0x01
38 #define RV3029_IRQ_CTRL_AIE BIT(0)
39 #define RV3029_IRQ_CTRL_TIE BIT(1)
40 #define RV3029_IRQ_CTRL_V1IE BIT(2)
41 #define RV3029_IRQ_CTRL_V2IE BIT(3)
42 #define RV3029_IRQ_CTRL_SRIE BIT(4)
43 #define RV3029_IRQ_FLAGS 0x02
44 #define RV3029_IRQ_FLAGS_AF BIT(0)
45 #define RV3029_IRQ_FLAGS_TF BIT(1)
46 #define RV3029_IRQ_FLAGS_V1IF BIT(2)
47 #define RV3029_IRQ_FLAGS_V2IF BIT(3)
48 #define RV3029_IRQ_FLAGS_SRF BIT(4)
49 #define RV3029_STATUS 0x03
50 #define RV3029_STATUS_VLOW1 BIT(2)
51 #define RV3029_STATUS_VLOW2 BIT(3)
52 #define RV3029_STATUS_SR BIT(4)
53 #define RV3029_STATUS_PON BIT(5)
54 #define RV3029_STATUS_EEBUSY BIT(7)
55 #define RV3029_RST_CTRL 0x04
56 #define RV3029_RST_CTRL_SYSR BIT(4)
57 #define RV3029_CONTROL_SECTION_LEN 0x05
58
59 /* watch section */
60 #define RV3029_W_SEC 0x08
61 #define RV3029_W_MINUTES 0x09
62 #define RV3029_W_HOURS 0x0A
63 #define RV3029_REG_HR_12_24 BIT(6) /* 24h/12h mode */
64 #define RV3029_REG_HR_PM BIT(5) /* PM/AM bit in 12h mode */
65 #define RV3029_W_DATE 0x0B
66 #define RV3029_W_DAYS 0x0C
67 #define RV3029_W_MONTHS 0x0D
68 #define RV3029_W_YEARS 0x0E
69 #define RV3029_WATCH_SECTION_LEN 0x07
70
71 /* alarm section */
72 #define RV3029_A_SC 0x10
73 #define RV3029_A_MN 0x11
74 #define RV3029_A_HR 0x12
75 #define RV3029_A_DT 0x13
76 #define RV3029_A_DW 0x14
77 #define RV3029_A_MO 0x15
78 #define RV3029_A_YR 0x16
79 #define RV3029_A_AE_X BIT(7)
80 #define RV3029_ALARM_SECTION_LEN 0x07
81
82 /* timer section */
83 #define RV3029_TIMER_LOW 0x18
84 #define RV3029_TIMER_HIGH 0x19
85
86 /* temperature section */
87 #define RV3029_TEMP_PAGE 0x20
88
89 /* eeprom data section */
90 #define RV3029_E2P_EEDATA1 0x28
91 #define RV3029_E2P_EEDATA2 0x29
92 #define RV3029_E2PDATA_SECTION_LEN 0x02
93
94 /* eeprom control section */
95 #define RV3029_CONTROL_E2P_EECTRL 0x30
96 #define RV3029_EECTRL_THP BIT(0) /* temp scan interval */
97 #define RV3029_EECTRL_THE BIT(1) /* thermometer enable */
98 #define RV3029_EECTRL_FD0 BIT(2) /* CLKOUT */
99 #define RV3029_EECTRL_FD1 BIT(3) /* CLKOUT */
100 #define RV3029_TRICKLE_1K BIT(4) /* 1.5K resistance */
101 #define RV3029_TRICKLE_5K BIT(5) /* 5K resistance */
102 #define RV3029_TRICKLE_20K BIT(6) /* 20K resistance */
103 #define RV3029_TRICKLE_80K BIT(7) /* 80K resistance */
104 #define RV3029_TRICKLE_MASK (RV3029_TRICKLE_1K |\
105 RV3029_TRICKLE_5K |\
106 RV3029_TRICKLE_20K |\
107 RV3029_TRICKLE_80K)
108 #define RV3029_TRICKLE_SHIFT 4
109 #define RV3029_CONTROL_E2P_XOFFS 0x31 /* XTAL offset */
110 #define RV3029_CONTROL_E2P_XOFFS_SIGN BIT(7) /* Sign: 1->pos, 0->neg */
111 #define RV3029_CONTROL_E2P_QCOEF 0x32 /* XTAL temp drift coef */
112 #define RV3029_CONTROL_E2P_TURNOVER 0x33 /* XTAL turnover temp (in *C) */
113 #define RV3029_CONTROL_E2P_TOV_MASK 0x3F /* XTAL turnover temp mask */
114
115 /* user ram section */
116 #define RV3029_USR1_RAM_PAGE 0x38
117 #define RV3029_USR1_SECTION_LEN 0x04
118 #define RV3029_USR2_RAM_PAGE 0x3C
119 #define RV3029_USR2_SECTION_LEN 0x04
120
121 struct rv3029_data {
122 struct device *dev;
123 struct rtc_device *rtc;
124 struct regmap *regmap;
125 int irq;
126 };
127
rv3029_read_regs(struct device * dev,u8 reg,u8 * buf,unsigned int len)128 static int rv3029_read_regs(struct device *dev, u8 reg, u8 *buf,
129 unsigned int len)
130 {
131 struct rv3029_data *rv3029 = dev_get_drvdata(dev);
132
133 if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
134 (reg + len > RV3029_USR1_RAM_PAGE + 8))
135 return -EINVAL;
136
137 return regmap_bulk_read(rv3029->regmap, reg, buf, len);
138 }
139
rv3029_write_regs(struct device * dev,u8 reg,u8 const buf[],unsigned int len)140 static int rv3029_write_regs(struct device *dev, u8 reg, u8 const buf[],
141 unsigned int len)
142 {
143 struct rv3029_data *rv3029 = dev_get_drvdata(dev);
144
145 if ((reg > RV3029_USR1_RAM_PAGE + 7) ||
146 (reg + len > RV3029_USR1_RAM_PAGE + 8))
147 return -EINVAL;
148
149 return regmap_bulk_write(rv3029->regmap, reg, buf, len);
150 }
151
rv3029_update_bits(struct device * dev,u8 reg,u8 mask,u8 set)152 static int rv3029_update_bits(struct device *dev, u8 reg, u8 mask, u8 set)
153 {
154 u8 buf;
155 int ret;
156
157 ret = rv3029_read_regs(dev, reg, &buf, 1);
158 if (ret < 0)
159 return ret;
160 buf &= ~mask;
161 buf |= set & mask;
162 ret = rv3029_write_regs(dev, reg, &buf, 1);
163 if (ret < 0)
164 return ret;
165
166 return 0;
167 }
168
rv3029_get_sr(struct device * dev,u8 * buf)169 static int rv3029_get_sr(struct device *dev, u8 *buf)
170 {
171 int ret = rv3029_read_regs(dev, RV3029_STATUS, buf, 1);
172
173 if (ret < 0)
174 return -EIO;
175 dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
176 return 0;
177 }
178
rv3029_set_sr(struct device * dev,u8 val)179 static int rv3029_set_sr(struct device *dev, u8 val)
180 {
181 u8 buf[1];
182 int sr;
183
184 buf[0] = val;
185 sr = rv3029_write_regs(dev, RV3029_STATUS, buf, 1);
186 dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
187 if (sr < 0)
188 return -EIO;
189 return 0;
190 }
191
rv3029_eeprom_busywait(struct device * dev)192 static int rv3029_eeprom_busywait(struct device *dev)
193 {
194 int i, ret;
195 u8 sr;
196
197 for (i = 100; i > 0; i--) {
198 ret = rv3029_get_sr(dev, &sr);
199 if (ret < 0)
200 break;
201 if (!(sr & RV3029_STATUS_EEBUSY))
202 break;
203 usleep_range(1000, 10000);
204 }
205 if (i <= 0) {
206 dev_err(dev, "EEPROM busy wait timeout.\n");
207 return -ETIMEDOUT;
208 }
209
210 return ret;
211 }
212
rv3029_eeprom_exit(struct device * dev)213 static int rv3029_eeprom_exit(struct device *dev)
214 {
215 /* Re-enable eeprom refresh */
216 return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
217 RV3029_ONOFF_CTRL_EERE,
218 RV3029_ONOFF_CTRL_EERE);
219 }
220
rv3029_eeprom_enter(struct device * dev)221 static int rv3029_eeprom_enter(struct device *dev)
222 {
223 int ret;
224 u8 sr;
225
226 /* Check whether we are in the allowed voltage range. */
227 ret = rv3029_get_sr(dev, &sr);
228 if (ret < 0)
229 return ret;
230 if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
231 /* We clear the bits and retry once just in case
232 * we had a brown out in early startup.
233 */
234 sr &= ~RV3029_STATUS_VLOW1;
235 sr &= ~RV3029_STATUS_VLOW2;
236 ret = rv3029_set_sr(dev, sr);
237 if (ret < 0)
238 return ret;
239 usleep_range(1000, 10000);
240 ret = rv3029_get_sr(dev, &sr);
241 if (ret < 0)
242 return ret;
243 if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
244 dev_err(dev,
245 "Supply voltage is too low to safely access the EEPROM.\n");
246 return -ENODEV;
247 }
248 }
249
250 /* Disable eeprom refresh. */
251 ret = rv3029_update_bits(dev, RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE,
252 0);
253 if (ret < 0)
254 return ret;
255
256 /* Wait for any previous eeprom accesses to finish. */
257 ret = rv3029_eeprom_busywait(dev);
258 if (ret < 0)
259 rv3029_eeprom_exit(dev);
260
261 return ret;
262 }
263
rv3029_eeprom_read(struct device * dev,u8 reg,u8 buf[],size_t len)264 static int rv3029_eeprom_read(struct device *dev, u8 reg,
265 u8 buf[], size_t len)
266 {
267 int ret, err;
268
269 err = rv3029_eeprom_enter(dev);
270 if (err < 0)
271 return err;
272
273 ret = rv3029_read_regs(dev, reg, buf, len);
274
275 err = rv3029_eeprom_exit(dev);
276 if (err < 0)
277 return err;
278
279 return ret;
280 }
281
rv3029_eeprom_write(struct device * dev,u8 reg,u8 const buf[],size_t len)282 static int rv3029_eeprom_write(struct device *dev, u8 reg,
283 u8 const buf[], size_t len)
284 {
285 int ret, err;
286 size_t i;
287 u8 tmp;
288
289 err = rv3029_eeprom_enter(dev);
290 if (err < 0)
291 return err;
292
293 for (i = 0; i < len; i++, reg++) {
294 ret = rv3029_read_regs(dev, reg, &tmp, 1);
295 if (ret < 0)
296 break;
297 if (tmp != buf[i]) {
298 ret = rv3029_write_regs(dev, reg, &buf[i], 1);
299 if (ret < 0)
300 break;
301 }
302 ret = rv3029_eeprom_busywait(dev);
303 if (ret < 0)
304 break;
305 }
306
307 err = rv3029_eeprom_exit(dev);
308 if (err < 0)
309 return err;
310
311 return ret;
312 }
313
rv3029_eeprom_update_bits(struct device * dev,u8 reg,u8 mask,u8 set)314 static int rv3029_eeprom_update_bits(struct device *dev,
315 u8 reg, u8 mask, u8 set)
316 {
317 u8 buf;
318 int ret;
319
320 ret = rv3029_eeprom_read(dev, reg, &buf, 1);
321 if (ret < 0)
322 return ret;
323 buf &= ~mask;
324 buf |= set & mask;
325 ret = rv3029_eeprom_write(dev, reg, &buf, 1);
326 if (ret < 0)
327 return ret;
328
329 return 0;
330 }
331
rv3029_handle_irq(int irq,void * dev_id)332 static irqreturn_t rv3029_handle_irq(int irq, void *dev_id)
333 {
334 struct device *dev = dev_id;
335 struct rv3029_data *rv3029 = dev_get_drvdata(dev);
336 struct mutex *lock = &rv3029->rtc->ops_lock;
337 unsigned long events = 0;
338 u8 flags, controls;
339 int ret;
340
341 mutex_lock(lock);
342
343 ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
344 if (ret) {
345 dev_warn(dev, "Read IRQ Control Register error %d\n", ret);
346 mutex_unlock(lock);
347 return IRQ_NONE;
348 }
349
350 ret = rv3029_read_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
351 if (ret) {
352 dev_warn(dev, "Read IRQ Flags Register error %d\n", ret);
353 mutex_unlock(lock);
354 return IRQ_NONE;
355 }
356
357 if (flags & RV3029_IRQ_FLAGS_AF) {
358 flags &= ~RV3029_IRQ_FLAGS_AF;
359 controls &= ~RV3029_IRQ_CTRL_AIE;
360 events |= RTC_AF;
361 }
362
363 if (events) {
364 rtc_update_irq(rv3029->rtc, 1, events);
365 rv3029_write_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
366 rv3029_write_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
367 }
368 mutex_unlock(lock);
369
370 return IRQ_HANDLED;
371 }
372
rv3029_read_time(struct device * dev,struct rtc_time * tm)373 static int rv3029_read_time(struct device *dev, struct rtc_time *tm)
374 {
375 u8 buf[1];
376 int ret;
377 u8 regs[RV3029_WATCH_SECTION_LEN] = { 0, };
378
379 ret = rv3029_get_sr(dev, buf);
380 if (ret < 0) {
381 dev_err(dev, "%s: reading SR failed\n", __func__);
382 return -EIO;
383 }
384
385 ret = rv3029_read_regs(dev, RV3029_W_SEC, regs,
386 RV3029_WATCH_SECTION_LEN);
387 if (ret < 0) {
388 dev_err(dev, "%s: reading RTC section failed\n", __func__);
389 return ret;
390 }
391
392 tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
393 tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
394
395 /* HR field has a more complex interpretation */
396 {
397 const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
398
399 if (_hr & RV3029_REG_HR_12_24) {
400 /* 12h format */
401 tm->tm_hour = bcd2bin(_hr & 0x1f);
402 if (_hr & RV3029_REG_HR_PM) /* PM flag set */
403 tm->tm_hour += 12;
404 } else /* 24h format */
405 tm->tm_hour = bcd2bin(_hr & 0x3f);
406 }
407
408 tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
409 tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
410 tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 100;
411 tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
412
413 return 0;
414 }
415
rv3029_read_alarm(struct device * dev,struct rtc_wkalrm * alarm)416 static int rv3029_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
417 {
418 struct rtc_time *const tm = &alarm->time;
419 int ret;
420 u8 regs[8], controls, flags;
421
422 ret = rv3029_get_sr(dev, regs);
423 if (ret < 0) {
424 dev_err(dev, "%s: reading SR failed\n", __func__);
425 return -EIO;
426 }
427
428 ret = rv3029_read_regs(dev, RV3029_A_SC, regs,
429 RV3029_ALARM_SECTION_LEN);
430
431 if (ret < 0) {
432 dev_err(dev, "%s: reading alarm section failed\n", __func__);
433 return ret;
434 }
435
436 ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
437 if (ret) {
438 dev_err(dev, "Read IRQ Control Register error %d\n", ret);
439 return ret;
440 }
441 ret = rv3029_read_regs(dev, RV3029_IRQ_FLAGS, &flags, 1);
442 if (ret < 0) {
443 dev_err(dev, "Read IRQ Flags Register error %d\n", ret);
444 return ret;
445 }
446
447 tm->tm_sec = bcd2bin(regs[RV3029_A_SC - RV3029_A_SC] & 0x7f);
448 tm->tm_min = bcd2bin(regs[RV3029_A_MN - RV3029_A_SC] & 0x7f);
449 tm->tm_hour = bcd2bin(regs[RV3029_A_HR - RV3029_A_SC] & 0x3f);
450 tm->tm_mday = bcd2bin(regs[RV3029_A_DT - RV3029_A_SC] & 0x3f);
451 tm->tm_mon = bcd2bin(regs[RV3029_A_MO - RV3029_A_SC] & 0x1f) - 1;
452 tm->tm_year = bcd2bin(regs[RV3029_A_YR - RV3029_A_SC] & 0x7f) + 100;
453 tm->tm_wday = bcd2bin(regs[RV3029_A_DW - RV3029_A_SC] & 0x07) - 1;
454
455 alarm->enabled = !!(controls & RV3029_IRQ_CTRL_AIE);
456 alarm->pending = (flags & RV3029_IRQ_FLAGS_AF) && alarm->enabled;
457
458 return 0;
459 }
460
rv3029_alarm_irq_enable(struct device * dev,unsigned int enable)461 static int rv3029_alarm_irq_enable(struct device *dev, unsigned int enable)
462 {
463 int ret;
464 u8 controls;
465
466 ret = rv3029_read_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
467 if (ret < 0) {
468 dev_warn(dev, "Read IRQ Control Register error %d\n", ret);
469 return ret;
470 }
471
472 /* enable/disable AIE irq */
473 if (enable)
474 controls |= RV3029_IRQ_CTRL_AIE;
475 else
476 controls &= ~RV3029_IRQ_CTRL_AIE;
477
478 ret = rv3029_write_regs(dev, RV3029_IRQ_CTRL, &controls, 1);
479 if (ret < 0) {
480 dev_err(dev, "can't update INT reg\n");
481 return ret;
482 }
483
484 return 0;
485 }
486
rv3029_set_alarm(struct device * dev,struct rtc_wkalrm * alarm)487 static int rv3029_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
488 {
489 struct rtc_time *const tm = &alarm->time;
490 int ret;
491 u8 regs[8];
492
493 /*
494 * The clock has an 8 bit wide bcd-coded register (they never learn)
495 * for the year. tm_year is an offset from 1900 and we are interested
496 * in the 2000-2099 range, so any value less than 100 is invalid.
497 */
498 if (tm->tm_year < 100)
499 return -EINVAL;
500
501 ret = rv3029_get_sr(dev, regs);
502 if (ret < 0) {
503 dev_err(dev, "%s: reading SR failed\n", __func__);
504 return -EIO;
505 }
506
507 /* Activate all the alarms with AE_x bit */
508 regs[RV3029_A_SC - RV3029_A_SC] = bin2bcd(tm->tm_sec) | RV3029_A_AE_X;
509 regs[RV3029_A_MN - RV3029_A_SC] = bin2bcd(tm->tm_min) | RV3029_A_AE_X;
510 regs[RV3029_A_HR - RV3029_A_SC] = (bin2bcd(tm->tm_hour) & 0x3f)
511 | RV3029_A_AE_X;
512 regs[RV3029_A_DT - RV3029_A_SC] = (bin2bcd(tm->tm_mday) & 0x3f)
513 | RV3029_A_AE_X;
514 regs[RV3029_A_MO - RV3029_A_SC] = (bin2bcd(tm->tm_mon + 1) & 0x1f)
515 | RV3029_A_AE_X;
516 regs[RV3029_A_DW - RV3029_A_SC] = (bin2bcd(tm->tm_wday + 1) & 0x7)
517 | RV3029_A_AE_X;
518 regs[RV3029_A_YR - RV3029_A_SC] = (bin2bcd(tm->tm_year - 100))
519 | RV3029_A_AE_X;
520
521 /* Write the alarm */
522 ret = rv3029_write_regs(dev, RV3029_A_SC, regs,
523 RV3029_ALARM_SECTION_LEN);
524 if (ret < 0)
525 return ret;
526
527 if (alarm->enabled) {
528 /* enable AIE irq */
529 ret = rv3029_alarm_irq_enable(dev, 1);
530 if (ret)
531 return ret;
532 } else {
533 /* disable AIE irq */
534 ret = rv3029_alarm_irq_enable(dev, 0);
535 if (ret)
536 return ret;
537 }
538
539 return 0;
540 }
541
rv3029_set_time(struct device * dev,struct rtc_time * tm)542 static int rv3029_set_time(struct device *dev, struct rtc_time *tm)
543 {
544 u8 regs[8];
545 int ret;
546
547 /*
548 * The clock has an 8 bit wide bcd-coded register (they never learn)
549 * for the year. tm_year is an offset from 1900 and we are interested
550 * in the 2000-2099 range, so any value less than 100 is invalid.
551 */
552 if (tm->tm_year < 100)
553 return -EINVAL;
554
555 regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
556 regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
557 regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
558 regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
559 regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
560 regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
561 regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 100);
562
563 ret = rv3029_write_regs(dev, RV3029_W_SEC, regs,
564 RV3029_WATCH_SECTION_LEN);
565 if (ret < 0)
566 return ret;
567
568 ret = rv3029_get_sr(dev, regs);
569 if (ret < 0) {
570 dev_err(dev, "%s: reading SR failed\n", __func__);
571 return ret;
572 }
573 /* clear PON bit */
574 ret = rv3029_set_sr(dev, (regs[0] & ~RV3029_STATUS_PON));
575 if (ret < 0) {
576 dev_err(dev, "%s: reading SR failed\n", __func__);
577 return ret;
578 }
579
580 return 0;
581 }
582
583 static const struct rv3029_trickle_tab_elem {
584 u32 r; /* resistance in ohms */
585 u8 conf; /* trickle config bits */
586 } rv3029_trickle_tab[] = {
587 {
588 .r = 1076,
589 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
590 RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
591 }, {
592 .r = 1091,
593 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
594 RV3029_TRICKLE_20K,
595 }, {
596 .r = 1137,
597 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
598 RV3029_TRICKLE_80K,
599 }, {
600 .r = 1154,
601 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,
602 }, {
603 .r = 1371,
604 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |
605 RV3029_TRICKLE_80K,
606 }, {
607 .r = 1395,
608 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,
609 }, {
610 .r = 1472,
611 .conf = RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,
612 }, {
613 .r = 1500,
614 .conf = RV3029_TRICKLE_1K,
615 }, {
616 .r = 3810,
617 .conf = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |
618 RV3029_TRICKLE_80K,
619 }, {
620 .r = 4000,
621 .conf = RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,
622 }, {
623 .r = 4706,
624 .conf = RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,
625 }, {
626 .r = 5000,
627 .conf = RV3029_TRICKLE_5K,
628 }, {
629 .r = 16000,
630 .conf = RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
631 }, {
632 .r = 20000,
633 .conf = RV3029_TRICKLE_20K,
634 }, {
635 .r = 80000,
636 .conf = RV3029_TRICKLE_80K,
637 },
638 };
639
rv3029_trickle_config(struct device * dev)640 static void rv3029_trickle_config(struct device *dev)
641 {
642 struct device_node *of_node = dev->of_node;
643 const struct rv3029_trickle_tab_elem *elem;
644 int i, err;
645 u32 ohms;
646 u8 trickle_set_bits;
647
648 if (!of_node)
649 return;
650
651 /* Configure the trickle charger. */
652 err = of_property_read_u32(of_node, "trickle-resistor-ohms", &ohms);
653 if (err) {
654 /* Disable trickle charger. */
655 trickle_set_bits = 0;
656 } else {
657 /* Enable trickle charger. */
658 for (i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++) {
659 elem = &rv3029_trickle_tab[i];
660 if (elem->r >= ohms)
661 break;
662 }
663 trickle_set_bits = elem->conf;
664 dev_info(dev,
665 "Trickle charger enabled at %d ohms resistance.\n",
666 elem->r);
667 }
668 err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
669 RV3029_TRICKLE_MASK,
670 trickle_set_bits);
671 if (err < 0)
672 dev_err(dev, "Failed to update trickle charger config\n");
673 }
674
675 #ifdef CONFIG_RTC_DRV_RV3029_HWMON
676
rv3029_read_temp(struct device * dev,int * temp_mC)677 static int rv3029_read_temp(struct device *dev, int *temp_mC)
678 {
679 int ret;
680 u8 temp;
681
682 ret = rv3029_read_regs(dev, RV3029_TEMP_PAGE, &temp, 1);
683 if (ret < 0)
684 return ret;
685
686 *temp_mC = ((int)temp - 60) * 1000;
687
688 return 0;
689 }
690
rv3029_hwmon_show_temp(struct device * dev,struct device_attribute * attr,char * buf)691 static ssize_t rv3029_hwmon_show_temp(struct device *dev,
692 struct device_attribute *attr,
693 char *buf)
694 {
695 int ret, temp_mC;
696
697 ret = rv3029_read_temp(dev, &temp_mC);
698 if (ret < 0)
699 return ret;
700
701 return sprintf(buf, "%d\n", temp_mC);
702 }
703
rv3029_hwmon_set_update_interval(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)704 static ssize_t rv3029_hwmon_set_update_interval(struct device *dev,
705 struct device_attribute *attr,
706 const char *buf,
707 size_t count)
708 {
709 unsigned long interval_ms;
710 int ret;
711 u8 th_set_bits = 0;
712
713 ret = kstrtoul(buf, 10, &interval_ms);
714 if (ret < 0)
715 return ret;
716
717 if (interval_ms != 0) {
718 th_set_bits |= RV3029_EECTRL_THE;
719 if (interval_ms >= 16000)
720 th_set_bits |= RV3029_EECTRL_THP;
721 }
722 ret = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
723 RV3029_EECTRL_THE | RV3029_EECTRL_THP,
724 th_set_bits);
725 if (ret < 0)
726 return ret;
727
728 return count;
729 }
730
rv3029_hwmon_show_update_interval(struct device * dev,struct device_attribute * attr,char * buf)731 static ssize_t rv3029_hwmon_show_update_interval(struct device *dev,
732 struct device_attribute *attr,
733 char *buf)
734 {
735 int ret, interval_ms;
736 u8 eectrl;
737
738 ret = rv3029_eeprom_read(dev, RV3029_CONTROL_E2P_EECTRL,
739 &eectrl, 1);
740 if (ret < 0)
741 return ret;
742
743 if (eectrl & RV3029_EECTRL_THE) {
744 if (eectrl & RV3029_EECTRL_THP)
745 interval_ms = 16000;
746 else
747 interval_ms = 1000;
748 } else {
749 interval_ms = 0;
750 }
751
752 return sprintf(buf, "%d\n", interval_ms);
753 }
754
755 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, rv3029_hwmon_show_temp,
756 NULL, 0);
757 static SENSOR_DEVICE_ATTR(update_interval, S_IWUSR | S_IRUGO,
758 rv3029_hwmon_show_update_interval,
759 rv3029_hwmon_set_update_interval, 0);
760
761 static struct attribute *rv3029_hwmon_attrs[] = {
762 &sensor_dev_attr_temp1_input.dev_attr.attr,
763 &sensor_dev_attr_update_interval.dev_attr.attr,
764 NULL,
765 };
766 ATTRIBUTE_GROUPS(rv3029_hwmon);
767
rv3029_hwmon_register(struct device * dev,const char * name)768 static void rv3029_hwmon_register(struct device *dev, const char *name)
769 {
770 struct rv3029_data *rv3029 = dev_get_drvdata(dev);
771 struct device *hwmon_dev;
772
773 hwmon_dev = devm_hwmon_device_register_with_groups(dev, name, rv3029,
774 rv3029_hwmon_groups);
775 if (IS_ERR(hwmon_dev)) {
776 dev_warn(dev, "unable to register hwmon device %ld\n",
777 PTR_ERR(hwmon_dev));
778 }
779 }
780
781 #else /* CONFIG_RTC_DRV_RV3029_HWMON */
782
rv3029_hwmon_register(struct device * dev,const char * name)783 static void rv3029_hwmon_register(struct device *dev, const char *name)
784 {
785 }
786
787 #endif /* CONFIG_RTC_DRV_RV3029_HWMON */
788
789 static struct rtc_class_ops rv3029_rtc_ops = {
790 .read_time = rv3029_read_time,
791 .set_time = rv3029_set_time,
792 };
793
rv3029_probe(struct device * dev,struct regmap * regmap,int irq,const char * name)794 static int rv3029_probe(struct device *dev, struct regmap *regmap, int irq,
795 const char *name)
796 {
797 struct rv3029_data *rv3029;
798 int rc = 0;
799 u8 buf[1];
800
801 rv3029 = devm_kzalloc(dev, sizeof(*rv3029), GFP_KERNEL);
802 if (!rv3029)
803 return -ENOMEM;
804
805 rv3029->regmap = regmap;
806 rv3029->irq = irq;
807 rv3029->dev = dev;
808 dev_set_drvdata(dev, rv3029);
809
810 rc = rv3029_get_sr(dev, buf);
811 if (rc < 0) {
812 dev_err(dev, "reading status failed\n");
813 return rc;
814 }
815
816 rv3029_trickle_config(dev);
817 rv3029_hwmon_register(dev, name);
818
819 rv3029->rtc = devm_rtc_device_register(dev, name, &rv3029_rtc_ops,
820 THIS_MODULE);
821 if (IS_ERR(rv3029->rtc)) {
822 dev_err(dev, "unable to register the class device\n");
823 return PTR_ERR(rv3029->rtc);
824 }
825
826 if (rv3029->irq > 0) {
827 rc = devm_request_threaded_irq(dev, rv3029->irq,
828 NULL, rv3029_handle_irq,
829 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
830 "rv3029", dev);
831 if (rc) {
832 dev_warn(dev, "unable to request IRQ, alarms disabled\n");
833 rv3029->irq = 0;
834 } else {
835 rv3029_rtc_ops.read_alarm = rv3029_read_alarm;
836 rv3029_rtc_ops.set_alarm = rv3029_set_alarm;
837 rv3029_rtc_ops.alarm_irq_enable = rv3029_alarm_irq_enable;
838 }
839 }
840
841 return 0;
842 }
843
844 #if IS_ENABLED(CONFIG_I2C)
845
rv3029_i2c_probe(struct i2c_client * client,const struct i2c_device_id * id)846 static int rv3029_i2c_probe(struct i2c_client *client,
847 const struct i2c_device_id *id)
848 {
849 struct regmap *regmap;
850 static const struct regmap_config config = {
851 .reg_bits = 8,
852 .val_bits = 8,
853 };
854
855 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_I2C_BLOCK |
856 I2C_FUNC_SMBUS_BYTE)) {
857 dev_err(&client->dev, "Adapter does not support SMBUS_I2C_BLOCK or SMBUS_I2C_BYTE\n");
858 return -ENODEV;
859 }
860
861 regmap = devm_regmap_init_i2c(client, &config);
862 if (IS_ERR(regmap)) {
863 dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
864 __func__, PTR_ERR(regmap));
865 return PTR_ERR(regmap);
866 }
867
868 return rv3029_probe(&client->dev, regmap, client->irq, client->name);
869 }
870
871 static struct i2c_device_id rv3029_id[] = {
872 { "rv3029", 0 },
873 { "rv3029c2", 0 },
874 { }
875 };
876 MODULE_DEVICE_TABLE(i2c, rv3029_id);
877
878 static struct i2c_driver rv3029_driver = {
879 .driver = {
880 .name = "rtc-rv3029c2",
881 },
882 .probe = rv3029_i2c_probe,
883 .id_table = rv3029_id,
884 };
885
rv3029_register_driver(void)886 static int rv3029_register_driver(void)
887 {
888 return i2c_add_driver(&rv3029_driver);
889 }
890
rv3029_unregister_driver(void)891 static void rv3029_unregister_driver(void)
892 {
893 i2c_del_driver(&rv3029_driver);
894 }
895
896 #else
897
rv3029_register_driver(void)898 static int rv3029_register_driver(void)
899 {
900 return 0;
901 }
902
rv3029_unregister_driver(void)903 static void rv3029_unregister_driver(void)
904 {
905 }
906
907 #endif
908
909 #if IS_ENABLED(CONFIG_SPI_MASTER)
910
rv3049_probe(struct spi_device * spi)911 static int rv3049_probe(struct spi_device *spi)
912 {
913 static const struct regmap_config config = {
914 .reg_bits = 8,
915 .val_bits = 8,
916 };
917 struct regmap *regmap;
918
919 regmap = devm_regmap_init_spi(spi, &config);
920 if (IS_ERR(regmap)) {
921 dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
922 __func__, PTR_ERR(regmap));
923 return PTR_ERR(regmap);
924 }
925
926 return rv3029_probe(&spi->dev, regmap, spi->irq, "rv3049");
927 }
928
929 static struct spi_driver rv3049_driver = {
930 .driver = {
931 .name = "rv3049",
932 },
933 .probe = rv3049_probe,
934 };
935
rv3049_register_driver(void)936 static int rv3049_register_driver(void)
937 {
938 return spi_register_driver(&rv3049_driver);
939 }
940
rv3049_unregister_driver(void)941 static void rv3049_unregister_driver(void)
942 {
943 spi_unregister_driver(&rv3049_driver);
944 }
945
946 #else
947
rv3049_register_driver(void)948 static int rv3049_register_driver(void)
949 {
950 return 0;
951 }
952
rv3049_unregister_driver(void)953 static void rv3049_unregister_driver(void)
954 {
955 }
956
957 #endif
958
rv30x9_init(void)959 static int __init rv30x9_init(void)
960 {
961 int ret;
962
963 ret = rv3029_register_driver();
964 if (ret) {
965 pr_err("Failed to register rv3029 driver: %d\n", ret);
966 return ret;
967 }
968
969 ret = rv3049_register_driver();
970 if (ret) {
971 pr_err("Failed to register rv3049 driver: %d\n", ret);
972 rv3029_unregister_driver();
973 }
974
975 return ret;
976 }
module_init(rv30x9_init)977 module_init(rv30x9_init)
978
979 static void __exit rv30x9_exit(void)
980 {
981 rv3049_unregister_driver();
982 rv3029_unregister_driver();
983 }
984 module_exit(rv30x9_exit)
985
986 MODULE_AUTHOR("Gregory Hermant <gregory.hermant@calao-systems.com>");
987 MODULE_AUTHOR("Michael Buesch <m@bues.ch>");
988 MODULE_DESCRIPTION("Micro Crystal RV3029/RV3049 RTC driver");
989 MODULE_LICENSE("GPL");
990 MODULE_ALIAS("spi:rv3049");
991