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1/*
2 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
3 *
4 * Copyright (C) 2005 James Chapman (ds1337 core)
5 * Copyright (C) 2006 David Brownell
6 * Copyright (C) 2009 Matthias Fuchs (rx8025 support)
7 * Copyright (C) 2012 Bertrand Achard (nvram access fixes)
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#include <linux/acpi.h>
15#include <linux/bcd.h>
16#include <linux/i2c.h>
17#include <linux/init.h>
18#include <linux/module.h>
19#include <linux/of_device.h>
20#include <linux/rtc/ds1307.h>
21#include <linux/rtc.h>
22#include <linux/slab.h>
23#include <linux/string.h>
24#include <linux/hwmon.h>
25#include <linux/hwmon-sysfs.h>
26#include <linux/clk-provider.h>
27#include <linux/regmap.h>
28
29/*
30 * We can't determine type by probing, but if we expect pre-Linux code
31 * to have set the chip up as a clock (turning on the oscillator and
32 * setting the date and time), Linux can ignore the non-clock features.
33 * That's a natural job for a factory or repair bench.
34 */
35enum ds_type {
36 ds_1307,
37 ds_1308,
38 ds_1337,
39 ds_1338,
40 ds_1339,
41 ds_1340,
42 ds_1341,
43 ds_1388,
44 ds_3231,
45 m41t0,
46 m41t00,
47 mcp794xx,
48 rx_8025,
49 rx_8130,
50 last_ds_type /* always last */
51 /* rs5c372 too? different address... */
52};
53
54/* RTC registers don't differ much, except for the century flag */
55#define DS1307_REG_SECS 0x00 /* 00-59 */
56# define DS1307_BIT_CH 0x80
57# define DS1340_BIT_nEOSC 0x80
58# define MCP794XX_BIT_ST 0x80
59#define DS1307_REG_MIN 0x01 /* 00-59 */
60# define M41T0_BIT_OF 0x80
61#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
62# define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
63# define DS1307_BIT_PM 0x20 /* in REG_HOUR */
64# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
65# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
66#define DS1307_REG_WDAY 0x03 /* 01-07 */
67# define MCP794XX_BIT_VBATEN 0x08
68#define DS1307_REG_MDAY 0x04 /* 01-31 */
69#define DS1307_REG_MONTH 0x05 /* 01-12 */
70# define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
71#define DS1307_REG_YEAR 0x06 /* 00-99 */
72
73/*
74 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
75 * start at 7, and they differ a LOT. Only control and status matter for
76 * basic RTC date and time functionality; be careful using them.
77 */
78#define DS1307_REG_CONTROL 0x07 /* or ds1338 */
79# define DS1307_BIT_OUT 0x80
80# define DS1338_BIT_OSF 0x20
81# define DS1307_BIT_SQWE 0x10
82# define DS1307_BIT_RS1 0x02
83# define DS1307_BIT_RS0 0x01
84#define DS1337_REG_CONTROL 0x0e
85# define DS1337_BIT_nEOSC 0x80
86# define DS1339_BIT_BBSQI 0x20
87# define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
88# define DS1337_BIT_RS2 0x10
89# define DS1337_BIT_RS1 0x08
90# define DS1337_BIT_INTCN 0x04
91# define DS1337_BIT_A2IE 0x02
92# define DS1337_BIT_A1IE 0x01
93#define DS1340_REG_CONTROL 0x07
94# define DS1340_BIT_OUT 0x80
95# define DS1340_BIT_FT 0x40
96# define DS1340_BIT_CALIB_SIGN 0x20
97# define DS1340_M_CALIBRATION 0x1f
98#define DS1340_REG_FLAG 0x09
99# define DS1340_BIT_OSF 0x80
100#define DS1337_REG_STATUS 0x0f
101# define DS1337_BIT_OSF 0x80
102# define DS3231_BIT_EN32KHZ 0x08
103# define DS1337_BIT_A2I 0x02
104# define DS1337_BIT_A1I 0x01
105#define DS1339_REG_ALARM1_SECS 0x07
106
107#define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
108
109#define RX8025_REG_CTRL1 0x0e
110# define RX8025_BIT_2412 0x20
111#define RX8025_REG_CTRL2 0x0f
112# define RX8025_BIT_PON 0x10
113# define RX8025_BIT_VDET 0x40
114# define RX8025_BIT_XST 0x20
115
116struct ds1307 {
117 enum ds_type type;
118 unsigned long flags;
119#define HAS_NVRAM 0 /* bit 0 == sysfs file active */
120#define HAS_ALARM 1 /* bit 1 == irq claimed */
121 struct device *dev;
122 struct regmap *regmap;
123 const char *name;
124 struct rtc_device *rtc;
125#ifdef CONFIG_COMMON_CLK
126 struct clk_hw clks[2];
127#endif
128};
129
130struct chip_desc {
131 unsigned alarm:1;
132 u16 nvram_offset;
133 u16 nvram_size;
134 u8 offset; /* register's offset */
135 u8 century_reg;
136 u8 century_enable_bit;
137 u8 century_bit;
138 u8 bbsqi_bit;
139 irq_handler_t irq_handler;
140 const struct rtc_class_ops *rtc_ops;
141 u16 trickle_charger_reg;
142 u8 (*do_trickle_setup)(struct ds1307 *, u32,
143 bool);
144};
145
146static int ds1307_get_time(struct device *dev, struct rtc_time *t);
147static int ds1307_set_time(struct device *dev, struct rtc_time *t);
148static u8 do_trickle_setup_ds1339(struct ds1307 *, u32 ohms, bool diode);
149static irqreturn_t rx8130_irq(int irq, void *dev_id);
150static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t);
151static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t);
152static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled);
153static irqreturn_t mcp794xx_irq(int irq, void *dev_id);
154static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t);
155static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t);
156static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled);
157
158static const struct rtc_class_ops rx8130_rtc_ops = {
159 .read_time = ds1307_get_time,
160 .set_time = ds1307_set_time,
161 .read_alarm = rx8130_read_alarm,
162 .set_alarm = rx8130_set_alarm,
163 .alarm_irq_enable = rx8130_alarm_irq_enable,
164};
165
166static const struct rtc_class_ops mcp794xx_rtc_ops = {
167 .read_time = ds1307_get_time,
168 .set_time = ds1307_set_time,
169 .read_alarm = mcp794xx_read_alarm,
170 .set_alarm = mcp794xx_set_alarm,
171 .alarm_irq_enable = mcp794xx_alarm_irq_enable,
172};
173
174static const struct chip_desc chips[last_ds_type] = {
175 [ds_1307] = {
176 .nvram_offset = 8,
177 .nvram_size = 56,
178 },
179 [ds_1308] = {
180 .nvram_offset = 8,
181 .nvram_size = 56,
182 },
183 [ds_1337] = {
184 .alarm = 1,
185 .century_reg = DS1307_REG_MONTH,
186 .century_bit = DS1337_BIT_CENTURY,
187 },
188 [ds_1338] = {
189 .nvram_offset = 8,
190 .nvram_size = 56,
191 },
192 [ds_1339] = {
193 .alarm = 1,
194 .century_reg = DS1307_REG_MONTH,
195 .century_bit = DS1337_BIT_CENTURY,
196 .bbsqi_bit = DS1339_BIT_BBSQI,
197 .trickle_charger_reg = 0x10,
198 .do_trickle_setup = &do_trickle_setup_ds1339,
199 },
200 [ds_1340] = {
201 .century_reg = DS1307_REG_HOUR,
202 .century_enable_bit = DS1340_BIT_CENTURY_EN,
203 .century_bit = DS1340_BIT_CENTURY,
204 .trickle_charger_reg = 0x08,
205 },
206 [ds_1341] = {
207 .century_reg = DS1307_REG_MONTH,
208 .century_bit = DS1337_BIT_CENTURY,
209 },
210 [ds_1388] = {
211 .offset = 1,
212 .trickle_charger_reg = 0x0a,
213 },
214 [ds_3231] = {
215 .alarm = 1,
216 .century_reg = DS1307_REG_MONTH,
217 .century_bit = DS1337_BIT_CENTURY,
218 .bbsqi_bit = DS3231_BIT_BBSQW,
219 },
220 [rx_8130] = {
221 .alarm = 1,
222 /* this is battery backed SRAM */
223 .nvram_offset = 0x20,
224 .nvram_size = 4, /* 32bit (4 word x 8 bit) */
225 .offset = 0x10,
226 .irq_handler = rx8130_irq,
227 .rtc_ops = &rx8130_rtc_ops,
228 },
229 [mcp794xx] = {
230 .alarm = 1,
231 /* this is battery backed SRAM */
232 .nvram_offset = 0x20,
233 .nvram_size = 0x40,
234 .irq_handler = mcp794xx_irq,
235 .rtc_ops = &mcp794xx_rtc_ops,
236 },
237};
238
239static const struct i2c_device_id ds1307_id[] = {
240 { "ds1307", ds_1307 },
241 { "ds1308", ds_1308 },
242 { "ds1337", ds_1337 },
243 { "ds1338", ds_1338 },
244 { "ds1339", ds_1339 },
245 { "ds1388", ds_1388 },
246 { "ds1340", ds_1340 },
247 { "ds1341", ds_1341 },
248 { "ds3231", ds_3231 },
249 { "m41t0", m41t0 },
250 { "m41t00", m41t00 },
251 { "mcp7940x", mcp794xx },
252 { "mcp7941x", mcp794xx },
253 { "pt7c4338", ds_1307 },
254 { "rx8025", rx_8025 },
255 { "isl12057", ds_1337 },
256 { "rx8130", rx_8130 },
257 { }
258};
259MODULE_DEVICE_TABLE(i2c, ds1307_id);
260
261#ifdef CONFIG_OF
262static const struct of_device_id ds1307_of_match[] = {
263 {
264 .compatible = "dallas,ds1307",
265 .data = (void *)ds_1307
266 },
267 {
268 .compatible = "dallas,ds1308",
269 .data = (void *)ds_1308
270 },
271 {
272 .compatible = "dallas,ds1337",
273 .data = (void *)ds_1337
274 },
275 {
276 .compatible = "dallas,ds1338",
277 .data = (void *)ds_1338
278 },
279 {
280 .compatible = "dallas,ds1339",
281 .data = (void *)ds_1339
282 },
283 {
284 .compatible = "dallas,ds1388",
285 .data = (void *)ds_1388
286 },
287 {
288 .compatible = "dallas,ds1340",
289 .data = (void *)ds_1340
290 },
291 {
292 .compatible = "dallas,ds1341",
293 .data = (void *)ds_1341
294 },
295 {
296 .compatible = "maxim,ds3231",
297 .data = (void *)ds_3231
298 },
299 {
300 .compatible = "st,m41t0",
301 .data = (void *)m41t00
302 },
303 {
304 .compatible = "st,m41t00",
305 .data = (void *)m41t00
306 },
307 {
308 .compatible = "microchip,mcp7940x",
309 .data = (void *)mcp794xx
310 },
311 {
312 .compatible = "microchip,mcp7941x",
313 .data = (void *)mcp794xx
314 },
315 {
316 .compatible = "pericom,pt7c4338",
317 .data = (void *)ds_1307
318 },
319 {
320 .compatible = "epson,rx8025",
321 .data = (void *)rx_8025
322 },
323 {
324 .compatible = "isil,isl12057",
325 .data = (void *)ds_1337
326 },
327 {
328 .compatible = "epson,rx8130",
329 .data = (void *)rx_8130
330 },
331 { }
332};
333MODULE_DEVICE_TABLE(of, ds1307_of_match);
334#endif
335
336#ifdef CONFIG_ACPI
337static const struct acpi_device_id ds1307_acpi_ids[] = {
338 { .id = "DS1307", .driver_data = ds_1307 },
339 { .id = "DS1308", .driver_data = ds_1308 },
340 { .id = "DS1337", .driver_data = ds_1337 },
341 { .id = "DS1338", .driver_data = ds_1338 },
342 { .id = "DS1339", .driver_data = ds_1339 },
343 { .id = "DS1388", .driver_data = ds_1388 },
344 { .id = "DS1340", .driver_data = ds_1340 },
345 { .id = "DS1341", .driver_data = ds_1341 },
346 { .id = "DS3231", .driver_data = ds_3231 },
347 { .id = "M41T0", .driver_data = m41t0 },
348 { .id = "M41T00", .driver_data = m41t00 },
349 { .id = "MCP7940X", .driver_data = mcp794xx },
350 { .id = "MCP7941X", .driver_data = mcp794xx },
351 { .id = "PT7C4338", .driver_data = ds_1307 },
352 { .id = "RX8025", .driver_data = rx_8025 },
353 { .id = "ISL12057", .driver_data = ds_1337 },
354 { .id = "RX8130", .driver_data = rx_8130 },
355 { }
356};
357MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
358#endif
359
360/*
361 * The ds1337 and ds1339 both have two alarms, but we only use the first
362 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
363 * signal; ds1339 chips have only one alarm signal.
364 */
365static irqreturn_t ds1307_irq(int irq, void *dev_id)
366{
367 struct ds1307 *ds1307 = dev_id;
368 struct mutex *lock = &ds1307->rtc->ops_lock;
369 int stat, ret;
370
371 mutex_lock(lock);
372 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
373 if (ret)
374 goto out;
375
376 if (stat & DS1337_BIT_A1I) {
377 stat &= ~DS1337_BIT_A1I;
378 regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
379
380 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
381 DS1337_BIT_A1IE, 0);
382 if (ret)
383 goto out;
384
385 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
386 }
387
388out:
389 mutex_unlock(lock);
390
391 return IRQ_HANDLED;
392}
393
394/*----------------------------------------------------------------------*/
395
396static int ds1307_get_time(struct device *dev, struct rtc_time *t)
397{
398 struct ds1307 *ds1307 = dev_get_drvdata(dev);
399 int tmp, ret;
400 const struct chip_desc *chip = &chips[ds1307->type];
401 u8 regs[7];
402
403 /* read the RTC date and time registers all at once */
404 ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
405 sizeof(regs));
406 if (ret) {
407 dev_err(dev, "%s error %d\n", "read", ret);
408 return ret;
409 }
410
411 dev_dbg(dev, "%s: %7ph\n", "read", regs);
412
413 /* if oscillator fail bit is set, no data can be trusted */
414 if (ds1307->type == m41t0 &&
415 regs[DS1307_REG_MIN] & M41T0_BIT_OF) {
416 dev_warn_once(dev, "oscillator failed, set time!\n");
417 return -EINVAL;
418 }
419
420 t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f);
421 t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f);
422 tmp = regs[DS1307_REG_HOUR] & 0x3f;
423 t->tm_hour = bcd2bin(tmp);
424 t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1;
425 t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f);
426 tmp = regs[DS1307_REG_MONTH] & 0x1f;
427 t->tm_mon = bcd2bin(tmp) - 1;
428 t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100;
429
430 if (regs[chip->century_reg] & chip->century_bit &&
431 IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY))
432 t->tm_year += 100;
433
434 dev_dbg(dev, "%s secs=%d, mins=%d, "
435 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
436 "read", t->tm_sec, t->tm_min,
437 t->tm_hour, t->tm_mday,
438 t->tm_mon, t->tm_year, t->tm_wday);
439
440 return 0;
441}
442
443static int ds1307_set_time(struct device *dev, struct rtc_time *t)
444{
445 struct ds1307 *ds1307 = dev_get_drvdata(dev);
446 const struct chip_desc *chip = &chips[ds1307->type];
447 int result;
448 int tmp;
449 u8 regs[7];
450
451 dev_dbg(dev, "%s secs=%d, mins=%d, "
452 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
453 "write", t->tm_sec, t->tm_min,
454 t->tm_hour, t->tm_mday,
455 t->tm_mon, t->tm_year, t->tm_wday);
456
457 if (t->tm_year < 100)
458 return -EINVAL;
459
460#ifdef CONFIG_RTC_DRV_DS1307_CENTURY
461 if (t->tm_year > (chip->century_bit ? 299 : 199))
462 return -EINVAL;
463#else
464 if (t->tm_year > 199)
465 return -EINVAL;
466#endif
467
468 regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
469 regs[DS1307_REG_MIN] = bin2bcd(t->tm_min);
470 regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
471 regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
472 regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
473 regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
474
475 /* assume 20YY not 19YY */
476 tmp = t->tm_year - 100;
477 regs[DS1307_REG_YEAR] = bin2bcd(tmp);
478
479 if (chip->century_enable_bit)
480 regs[chip->century_reg] |= chip->century_enable_bit;
481 if (t->tm_year > 199 && chip->century_bit)
482 regs[chip->century_reg] |= chip->century_bit;
483
484 if (ds1307->type == mcp794xx) {
485 /*
486 * these bits were cleared when preparing the date/time
487 * values and need to be set again before writing the
488 * regsfer out to the device.
489 */
490 regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
491 regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
492 }
493
494 dev_dbg(dev, "%s: %7ph\n", "write", regs);
495
496 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,
497 sizeof(regs));
498 if (result) {
499 dev_err(dev, "%s error %d\n", "write", result);
500 return result;
501 }
502 return 0;
503}
504
505static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
506{
507 struct ds1307 *ds1307 = dev_get_drvdata(dev);
508 int ret;
509 u8 regs[9];
510
511 if (!test_bit(HAS_ALARM, &ds1307->flags))
512 return -EINVAL;
513
514 /* read all ALARM1, ALARM2, and status registers at once */
515 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS,
516 regs, sizeof(regs));
517 if (ret) {
518 dev_err(dev, "%s error %d\n", "alarm read", ret);
519 return ret;
520 }
521
522 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
523 ®s[0], ®s[4], ®s[7]);
524
525 /*
526 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
527 * and that all four fields are checked matches
528 */
529 t->time.tm_sec = bcd2bin(regs[0] & 0x7f);
530 t->time.tm_min = bcd2bin(regs[1] & 0x7f);
531 t->time.tm_hour = bcd2bin(regs[2] & 0x3f);
532 t->time.tm_mday = bcd2bin(regs[3] & 0x3f);
533
534 /* ... and status */
535 t->enabled = !!(regs[7] & DS1337_BIT_A1IE);
536 t->pending = !!(regs[8] & DS1337_BIT_A1I);
537
538 dev_dbg(dev, "%s secs=%d, mins=%d, "
539 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
540 "alarm read", t->time.tm_sec, t->time.tm_min,
541 t->time.tm_hour, t->time.tm_mday,
542 t->enabled, t->pending);
543
544 return 0;
545}
546
547static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
548{
549 struct ds1307 *ds1307 = dev_get_drvdata(dev);
550 unsigned char regs[9];
551 u8 control, status;
552 int ret;
553
554 if (!test_bit(HAS_ALARM, &ds1307->flags))
555 return -EINVAL;
556
557 dev_dbg(dev, "%s secs=%d, mins=%d, "
558 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
559 "alarm set", t->time.tm_sec, t->time.tm_min,
560 t->time.tm_hour, t->time.tm_mday,
561 t->enabled, t->pending);
562
563 /* read current status of both alarms and the chip */
564 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
565 sizeof(regs));
566 if (ret) {
567 dev_err(dev, "%s error %d\n", "alarm write", ret);
568 return ret;
569 }
570 control = regs[7];
571 status = regs[8];
572
573 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
574 ®s[0], ®s[4], control, status);
575
576 /* set ALARM1, using 24 hour and day-of-month modes */
577 regs[0] = bin2bcd(t->time.tm_sec);
578 regs[1] = bin2bcd(t->time.tm_min);
579 regs[2] = bin2bcd(t->time.tm_hour);
580 regs[3] = bin2bcd(t->time.tm_mday);
581
582 /* set ALARM2 to non-garbage */
583 regs[4] = 0;
584 regs[5] = 0;
585 regs[6] = 0;
586
587 /* disable alarms */
588 regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
589 regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
590
591 ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
592 sizeof(regs));
593 if (ret) {
594 dev_err(dev, "can't set alarm time\n");
595 return ret;
596 }
597
598 /* optionally enable ALARM1 */
599 if (t->enabled) {
600 dev_dbg(dev, "alarm IRQ armed\n");
601 regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
602 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]);
603 }
604
605 return 0;
606}
607
608static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
609{
610 struct ds1307 *ds1307 = dev_get_drvdata(dev);
611
612 if (!test_bit(HAS_ALARM, &ds1307->flags))
613 return -ENOTTY;
614
615 return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
616 DS1337_BIT_A1IE,
617 enabled ? DS1337_BIT_A1IE : 0);
618}
619
620static const struct rtc_class_ops ds13xx_rtc_ops = {
621 .read_time = ds1307_get_time,
622 .set_time = ds1307_set_time,
623 .read_alarm = ds1337_read_alarm,
624 .set_alarm = ds1337_set_alarm,
625 .alarm_irq_enable = ds1307_alarm_irq_enable,
626};
627
628/*----------------------------------------------------------------------*/
629
630/*
631 * Alarm support for rx8130 devices.
632 */
633
634#define RX8130_REG_ALARM_MIN 0x07
635#define RX8130_REG_ALARM_HOUR 0x08
636#define RX8130_REG_ALARM_WEEK_OR_DAY 0x09
637#define RX8130_REG_EXTENSION 0x0c
638#define RX8130_REG_EXTENSION_WADA BIT(3)
639#define RX8130_REG_FLAG 0x0d
640#define RX8130_REG_FLAG_AF BIT(3)
641#define RX8130_REG_CONTROL0 0x0e
642#define RX8130_REG_CONTROL0_AIE BIT(3)
643
644static irqreturn_t rx8130_irq(int irq, void *dev_id)
645{
646 struct ds1307 *ds1307 = dev_id;
647 struct mutex *lock = &ds1307->rtc->ops_lock;
648 u8 ctl[3];
649 int ret;
650
651 mutex_lock(lock);
652
653 /* Read control registers. */
654 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
655 sizeof(ctl));
656 if (ret < 0)
657 goto out;
658 if (!(ctl[1] & RX8130_REG_FLAG_AF))
659 goto out;
660 ctl[1] &= ~RX8130_REG_FLAG_AF;
661 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
662
663 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
664 sizeof(ctl));
665 if (ret < 0)
666 goto out;
667
668 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
669
670out:
671 mutex_unlock(lock);
672
673 return IRQ_HANDLED;
674}
675
676static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t)
677{
678 struct ds1307 *ds1307 = dev_get_drvdata(dev);
679 u8 ald[3], ctl[3];
680 int ret;
681
682 if (!test_bit(HAS_ALARM, &ds1307->flags))
683 return -EINVAL;
684
685 /* Read alarm registers. */
686 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
687 sizeof(ald));
688 if (ret < 0)
689 return ret;
690
691 /* Read control registers. */
692 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
693 sizeof(ctl));
694 if (ret < 0)
695 return ret;
696
697 t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE);
698 t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF);
699
700 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
701 t->time.tm_sec = -1;
702 t->time.tm_min = bcd2bin(ald[0] & 0x7f);
703 t->time.tm_hour = bcd2bin(ald[1] & 0x7f);
704 t->time.tm_wday = -1;
705 t->time.tm_mday = bcd2bin(ald[2] & 0x7f);
706 t->time.tm_mon = -1;
707 t->time.tm_year = -1;
708 t->time.tm_yday = -1;
709 t->time.tm_isdst = -1;
710
711 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n",
712 __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
713 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled);
714
715 return 0;
716}
717
718static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
719{
720 struct ds1307 *ds1307 = dev_get_drvdata(dev);
721 u8 ald[3], ctl[3];
722 int ret;
723
724 if (!test_bit(HAS_ALARM, &ds1307->flags))
725 return -EINVAL;
726
727 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
728 "enabled=%d pending=%d\n", __func__,
729 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
730 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
731 t->enabled, t->pending);
732
733 /* Read control registers. */
734 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
735 sizeof(ctl));
736 if (ret < 0)
737 return ret;
738
739 ctl[0] &= ~RX8130_REG_EXTENSION_WADA;
740 ctl[1] |= RX8130_REG_FLAG_AF;
741 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
742
743 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
744 sizeof(ctl));
745 if (ret < 0)
746 return ret;
747
748 /* Hardware alarm precision is 1 minute! */
749 ald[0] = bin2bcd(t->time.tm_min);
750 ald[1] = bin2bcd(t->time.tm_hour);
751 ald[2] = bin2bcd(t->time.tm_mday);
752
753 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
754 sizeof(ald));
755 if (ret < 0)
756 return ret;
757
758 if (!t->enabled)
759 return 0;
760
761 ctl[2] |= RX8130_REG_CONTROL0_AIE;
762
763 return regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
764 sizeof(ctl));
765}
766
767static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
768{
769 struct ds1307 *ds1307 = dev_get_drvdata(dev);
770 int ret, reg;
771
772 if (!test_bit(HAS_ALARM, &ds1307->flags))
773 return -EINVAL;
774
775 ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®);
776 if (ret < 0)
777 return ret;
778
779 if (enabled)
780 reg |= RX8130_REG_CONTROL0_AIE;
781 else
782 reg &= ~RX8130_REG_CONTROL0_AIE;
783
784 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg);
785}
786
787/*----------------------------------------------------------------------*/
788
789/*
790 * Alarm support for mcp794xx devices.
791 */
792
793#define MCP794XX_REG_CONTROL 0x07
794# define MCP794XX_BIT_ALM0_EN 0x10
795# define MCP794XX_BIT_ALM1_EN 0x20
796#define MCP794XX_REG_ALARM0_BASE 0x0a
797#define MCP794XX_REG_ALARM0_CTRL 0x0d
798#define MCP794XX_REG_ALARM1_BASE 0x11
799#define MCP794XX_REG_ALARM1_CTRL 0x14
800# define MCP794XX_BIT_ALMX_IF BIT(3)
801# define MCP794XX_BIT_ALMX_C0 BIT(4)
802# define MCP794XX_BIT_ALMX_C1 BIT(5)
803# define MCP794XX_BIT_ALMX_C2 BIT(6)
804# define MCP794XX_BIT_ALMX_POL BIT(7)
805# define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
806 MCP794XX_BIT_ALMX_C1 | \
807 MCP794XX_BIT_ALMX_C2)
808
809static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
810{
811 struct ds1307 *ds1307 = dev_id;
812 struct mutex *lock = &ds1307->rtc->ops_lock;
813 int reg, ret;
814
815 mutex_lock(lock);
816
817 /* Check and clear alarm 0 interrupt flag. */
818 ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®);
819 if (ret)
820 goto out;
821 if (!(reg & MCP794XX_BIT_ALMX_IF))
822 goto out;
823 reg &= ~MCP794XX_BIT_ALMX_IF;
824 ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg);
825 if (ret)
826 goto out;
827
828 /* Disable alarm 0. */
829 ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
830 MCP794XX_BIT_ALM0_EN, 0);
831 if (ret)
832 goto out;
833
834 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
835
836out:
837 mutex_unlock(lock);
838
839 return IRQ_HANDLED;
840}
841
842static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)
843{
844 struct ds1307 *ds1307 = dev_get_drvdata(dev);
845 u8 regs[10];
846 int ret;
847
848 if (!test_bit(HAS_ALARM, &ds1307->flags))
849 return -EINVAL;
850
851 /* Read control and alarm 0 registers. */
852 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
853 sizeof(regs));
854 if (ret)
855 return ret;
856
857 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);
858
859 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
860 t->time.tm_sec = bcd2bin(regs[3] & 0x7f);
861 t->time.tm_min = bcd2bin(regs[4] & 0x7f);
862 t->time.tm_hour = bcd2bin(regs[5] & 0x3f);
863 t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1;
864 t->time.tm_mday = bcd2bin(regs[7] & 0x3f);
865 t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1;
866 t->time.tm_year = -1;
867 t->time.tm_yday = -1;
868 t->time.tm_isdst = -1;
869
870 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
871 "enabled=%d polarity=%d irq=%d match=%lu\n", __func__,
872 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
873 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
874 !!(regs[6] & MCP794XX_BIT_ALMX_POL),
875 !!(regs[6] & MCP794XX_BIT_ALMX_IF),
876 (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
877
878 return 0;
879}
880
881/*
882 * We may have a random RTC weekday, therefore calculate alarm weekday based
883 * on current weekday we read from the RTC timekeeping regs
884 */
885static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm)
886{
887 struct rtc_time tm_now;
888 int days_now, days_alarm, ret;
889
890 ret = ds1307_get_time(dev, &tm_now);
891 if (ret)
892 return ret;
893
894 days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60);
895 days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60);
896
897 return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1;
898}
899
900static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
901{
902 struct ds1307 *ds1307 = dev_get_drvdata(dev);
903 unsigned char regs[10];
904 int wday, ret;
905
906 if (!test_bit(HAS_ALARM, &ds1307->flags))
907 return -EINVAL;
908
909 wday = mcp794xx_alm_weekday(dev, &t->time);
910 if (wday < 0)
911 return wday;
912
913 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
914 "enabled=%d pending=%d\n", __func__,
915 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
916 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
917 t->enabled, t->pending);
918
919 /* Read control and alarm 0 registers. */
920 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
921 sizeof(regs));
922 if (ret)
923 return ret;
924
925 /* Set alarm 0, using 24-hour and day-of-month modes. */
926 regs[3] = bin2bcd(t->time.tm_sec);
927 regs[4] = bin2bcd(t->time.tm_min);
928 regs[5] = bin2bcd(t->time.tm_hour);
929 regs[6] = wday;
930 regs[7] = bin2bcd(t->time.tm_mday);
931 regs[8] = bin2bcd(t->time.tm_mon + 1);
932
933 /* Clear the alarm 0 interrupt flag. */
934 regs[6] &= ~MCP794XX_BIT_ALMX_IF;
935 /* Set alarm match: second, minute, hour, day, date, month. */
936 regs[6] |= MCP794XX_MSK_ALMX_MATCH;
937 /* Disable interrupt. We will not enable until completely programmed */
938 regs[0] &= ~MCP794XX_BIT_ALM0_EN;
939
940 ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
941 sizeof(regs));
942 if (ret)
943 return ret;
944
945 if (!t->enabled)
946 return 0;
947 regs[0] |= MCP794XX_BIT_ALM0_EN;
948 return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]);
949}
950
951static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
952{
953 struct ds1307 *ds1307 = dev_get_drvdata(dev);
954
955 if (!test_bit(HAS_ALARM, &ds1307->flags))
956 return -EINVAL;
957
958 return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
959 MCP794XX_BIT_ALM0_EN,
960 enabled ? MCP794XX_BIT_ALM0_EN : 0);
961}
962
963/*----------------------------------------------------------------------*/
964
965static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,
966 size_t bytes)
967{
968 struct ds1307 *ds1307 = priv;
969 const struct chip_desc *chip = &chips[ds1307->type];
970
971 return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset,
972 val, bytes);
973}
974
975static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
976 size_t bytes)
977{
978 struct ds1307 *ds1307 = priv;
979 const struct chip_desc *chip = &chips[ds1307->type];
980
981 return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset,
982 val, bytes);
983}
984
985/*----------------------------------------------------------------------*/
986
987static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307,
988 u32 ohms, bool diode)
989{
990 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
991 DS1307_TRICKLE_CHARGER_NO_DIODE;
992
993 switch (ohms) {
994 case 250:
995 setup |= DS1307_TRICKLE_CHARGER_250_OHM;
996 break;
997 case 2000:
998 setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
999 break;
1000 case 4000:
1001 setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
1002 break;
1003 default:
1004 dev_warn(ds1307->dev,
1005 "Unsupported ohm value %u in dt\n", ohms);
1006 return 0;
1007 }
1008 return setup;
1009}
1010
1011static u8 ds1307_trickle_init(struct ds1307 *ds1307,
1012 const struct chip_desc *chip)
1013{
1014 u32 ohms;
1015 bool diode = true;
1016
1017 if (!chip->do_trickle_setup)
1018 return 0;
1019
1020 if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms",
1021 &ohms))
1022 return 0;
1023
1024 if (device_property_read_bool(ds1307->dev, "trickle-diode-disable"))
1025 diode = false;
1026
1027 return chip->do_trickle_setup(ds1307, ohms, diode);
1028}
1029
1030/*----------------------------------------------------------------------*/
1031
1032#ifdef CONFIG_RTC_DRV_DS1307_HWMON
1033
1034/*
1035 * Temperature sensor support for ds3231 devices.
1036 */
1037
1038#define DS3231_REG_TEMPERATURE 0x11
1039
1040/*
1041 * A user-initiated temperature conversion is not started by this function,
1042 * so the temperature is updated once every 64 seconds.
1043 */
1044static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)
1045{
1046 struct ds1307 *ds1307 = dev_get_drvdata(dev);
1047 u8 temp_buf[2];
1048 s16 temp;
1049 int ret;
1050
1051 ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE,
1052 temp_buf, sizeof(temp_buf));
1053 if (ret)
1054 return ret;
1055 /*
1056 * Temperature is represented as a 10-bit code with a resolution of
1057 * 0.25 degree celsius and encoded in two's complement format.
1058 */
1059 temp = (temp_buf[0] << 8) | temp_buf[1];
1060 temp >>= 6;
1061 *mC = temp * 250;
1062
1063 return 0;
1064}
1065
1066static ssize_t ds3231_hwmon_show_temp(struct device *dev,
1067 struct device_attribute *attr, char *buf)
1068{
1069 int ret;
1070 s32 temp;
1071
1072 ret = ds3231_hwmon_read_temp(dev, &temp);
1073 if (ret)
1074 return ret;
1075
1076 return sprintf(buf, "%d\n", temp);
1077}
1078static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp,
1079 NULL, 0);
1080
1081static struct attribute *ds3231_hwmon_attrs[] = {
1082 &sensor_dev_attr_temp1_input.dev_attr.attr,
1083 NULL,
1084};
1085ATTRIBUTE_GROUPS(ds3231_hwmon);
1086
1087static void ds1307_hwmon_register(struct ds1307 *ds1307)
1088{
1089 struct device *dev;
1090
1091 if (ds1307->type != ds_3231)
1092 return;
1093
1094 dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name,
1095 ds1307,
1096 ds3231_hwmon_groups);
1097 if (IS_ERR(dev)) {
1098 dev_warn(ds1307->dev, "unable to register hwmon device %ld\n",
1099 PTR_ERR(dev));
1100 }
1101}
1102
1103#else
1104
1105static void ds1307_hwmon_register(struct ds1307 *ds1307)
1106{
1107}
1108
1109#endif /* CONFIG_RTC_DRV_DS1307_HWMON */
1110
1111/*----------------------------------------------------------------------*/
1112
1113/*
1114 * Square-wave output support for DS3231
1115 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf
1116 */
1117#ifdef CONFIG_COMMON_CLK
1118
1119enum {
1120 DS3231_CLK_SQW = 0,
1121 DS3231_CLK_32KHZ,
1122};
1123
1124#define clk_sqw_to_ds1307(clk) \
1125 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW])
1126#define clk_32khz_to_ds1307(clk) \
1127 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ])
1128
1129static int ds3231_clk_sqw_rates[] = {
1130 1,
1131 1024,
1132 4096,
1133 8192,
1134};
1135
1136static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value)
1137{
1138 struct mutex *lock = &ds1307->rtc->ops_lock;
1139 int ret;
1140
1141 mutex_lock(lock);
1142 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1143 mask, value);
1144 mutex_unlock(lock);
1145
1146 return ret;
1147}
1148
1149static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw,
1150 unsigned long parent_rate)
1151{
1152 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1153 int control, ret;
1154 int rate_sel = 0;
1155
1156 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1157 if (ret)
1158 return ret;
1159 if (control & DS1337_BIT_RS1)
1160 rate_sel += 1;
1161 if (control & DS1337_BIT_RS2)
1162 rate_sel += 2;
1163
1164 return ds3231_clk_sqw_rates[rate_sel];
1165}
1166
1167static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
1168 unsigned long *prate)
1169{
1170 int i;
1171
1172 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) {
1173 if (ds3231_clk_sqw_rates[i] <= rate)
1174 return ds3231_clk_sqw_rates[i];
1175 }
1176
1177 return 0;
1178}
1179
1180static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
1181 unsigned long parent_rate)
1182{
1183 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1184 int control = 0;
1185 int rate_sel;
1186
1187 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates);
1188 rate_sel++) {
1189 if (ds3231_clk_sqw_rates[rate_sel] == rate)
1190 break;
1191 }
1192
1193 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates))
1194 return -EINVAL;
1195
1196 if (rate_sel & 1)
1197 control |= DS1337_BIT_RS1;
1198 if (rate_sel & 2)
1199 control |= DS1337_BIT_RS2;
1200
1201 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2,
1202 control);
1203}
1204
1205static int ds3231_clk_sqw_prepare(struct clk_hw *hw)
1206{
1207 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1208
1209 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0);
1210}
1211
1212static void ds3231_clk_sqw_unprepare(struct clk_hw *hw)
1213{
1214 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1215
1216 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN);
1217}
1218
1219static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw)
1220{
1221 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1222 int control, ret;
1223
1224 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1225 if (ret)
1226 return ret;
1227
1228 return !(control & DS1337_BIT_INTCN);
1229}
1230
1231static const struct clk_ops ds3231_clk_sqw_ops = {
1232 .prepare = ds3231_clk_sqw_prepare,
1233 .unprepare = ds3231_clk_sqw_unprepare,
1234 .is_prepared = ds3231_clk_sqw_is_prepared,
1235 .recalc_rate = ds3231_clk_sqw_recalc_rate,
1236 .round_rate = ds3231_clk_sqw_round_rate,
1237 .set_rate = ds3231_clk_sqw_set_rate,
1238};
1239
1240static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw,
1241 unsigned long parent_rate)
1242{
1243 return 32768;
1244}
1245
1246static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable)
1247{
1248 struct mutex *lock = &ds1307->rtc->ops_lock;
1249 int ret;
1250
1251 mutex_lock(lock);
1252 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS,
1253 DS3231_BIT_EN32KHZ,
1254 enable ? DS3231_BIT_EN32KHZ : 0);
1255 mutex_unlock(lock);
1256
1257 return ret;
1258}
1259
1260static int ds3231_clk_32khz_prepare(struct clk_hw *hw)
1261{
1262 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1263
1264 return ds3231_clk_32khz_control(ds1307, true);
1265}
1266
1267static void ds3231_clk_32khz_unprepare(struct clk_hw *hw)
1268{
1269 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1270
1271 ds3231_clk_32khz_control(ds1307, false);
1272}
1273
1274static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw)
1275{
1276 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1277 int status, ret;
1278
1279 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status);
1280 if (ret)
1281 return ret;
1282
1283 return !!(status & DS3231_BIT_EN32KHZ);
1284}
1285
1286static const struct clk_ops ds3231_clk_32khz_ops = {
1287 .prepare = ds3231_clk_32khz_prepare,
1288 .unprepare = ds3231_clk_32khz_unprepare,
1289 .is_prepared = ds3231_clk_32khz_is_prepared,
1290 .recalc_rate = ds3231_clk_32khz_recalc_rate,
1291};
1292
1293static struct clk_init_data ds3231_clks_init[] = {
1294 [DS3231_CLK_SQW] = {
1295 .name = "ds3231_clk_sqw",
1296 .ops = &ds3231_clk_sqw_ops,
1297 },
1298 [DS3231_CLK_32KHZ] = {
1299 .name = "ds3231_clk_32khz",
1300 .ops = &ds3231_clk_32khz_ops,
1301 },
1302};
1303
1304static int ds3231_clks_register(struct ds1307 *ds1307)
1305{
1306 struct device_node *node = ds1307->dev->of_node;
1307 struct clk_onecell_data *onecell;
1308 int i;
1309
1310 onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL);
1311 if (!onecell)
1312 return -ENOMEM;
1313
1314 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init);
1315 onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num,
1316 sizeof(onecell->clks[0]), GFP_KERNEL);
1317 if (!onecell->clks)
1318 return -ENOMEM;
1319
1320 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) {
1321 struct clk_init_data init = ds3231_clks_init[i];
1322
1323 /*
1324 * Interrupt signal due to alarm conditions and square-wave
1325 * output share same pin, so don't initialize both.
1326 */
1327 if (i == DS3231_CLK_SQW && test_bit(HAS_ALARM, &ds1307->flags))
1328 continue;
1329
1330 /* optional override of the clockname */
1331 of_property_read_string_index(node, "clock-output-names", i,
1332 &init.name);
1333 ds1307->clks[i].init = &init;
1334
1335 onecell->clks[i] = devm_clk_register(ds1307->dev,
1336 &ds1307->clks[i]);
1337 if (IS_ERR(onecell->clks[i]))
1338 return PTR_ERR(onecell->clks[i]);
1339 }
1340
1341 if (!node)
1342 return 0;
1343
1344 of_clk_add_provider(node, of_clk_src_onecell_get, onecell);
1345
1346 return 0;
1347}
1348
1349static void ds1307_clks_register(struct ds1307 *ds1307)
1350{
1351 int ret;
1352
1353 if (ds1307->type != ds_3231)
1354 return;
1355
1356 ret = ds3231_clks_register(ds1307);
1357 if (ret) {
1358 dev_warn(ds1307->dev, "unable to register clock device %d\n",
1359 ret);
1360 }
1361}
1362
1363#else
1364
1365static void ds1307_clks_register(struct ds1307 *ds1307)
1366{
1367}
1368
1369#endif /* CONFIG_COMMON_CLK */
1370
1371static const struct regmap_config regmap_config = {
1372 .reg_bits = 8,
1373 .val_bits = 8,
1374};
1375
1376static int ds1307_probe(struct i2c_client *client,
1377 const struct i2c_device_id *id)
1378{
1379 struct ds1307 *ds1307;
1380 int err = -ENODEV;
1381 int tmp;
1382 const struct chip_desc *chip;
1383 bool want_irq;
1384 bool ds1307_can_wakeup_device = false;
1385 unsigned char regs[8];
1386 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
1387 u8 trickle_charger_setup = 0;
1388
1389 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
1390 if (!ds1307)
1391 return -ENOMEM;
1392
1393 dev_set_drvdata(&client->dev, ds1307);
1394 ds1307->dev = &client->dev;
1395 ds1307->name = client->name;
1396
1397 ds1307->regmap = devm_regmap_init_i2c(client, ®map_config);
1398 if (IS_ERR(ds1307->regmap)) {
1399 dev_err(ds1307->dev, "regmap allocation failed\n");
1400 return PTR_ERR(ds1307->regmap);
1401 }
1402
1403 i2c_set_clientdata(client, ds1307);
1404
1405 if (client->dev.of_node) {
1406 ds1307->type = (enum ds_type)
1407 of_device_get_match_data(&client->dev);
1408 chip = &chips[ds1307->type];
1409 } else if (id) {
1410 chip = &chips[id->driver_data];
1411 ds1307->type = id->driver_data;
1412 } else {
1413 const struct acpi_device_id *acpi_id;
1414
1415 acpi_id = acpi_match_device(ACPI_PTR(ds1307_acpi_ids),
1416 ds1307->dev);
1417 if (!acpi_id)
1418 return -ENODEV;
1419 chip = &chips[acpi_id->driver_data];
1420 ds1307->type = acpi_id->driver_data;
1421 }
1422
1423 want_irq = client->irq > 0 && chip->alarm;
1424
1425 if (!pdata)
1426 trickle_charger_setup = ds1307_trickle_init(ds1307, chip);
1427 else if (pdata->trickle_charger_setup)
1428 trickle_charger_setup = pdata->trickle_charger_setup;
1429
1430 if (trickle_charger_setup && chip->trickle_charger_reg) {
1431 trickle_charger_setup |= DS13XX_TRICKLE_CHARGER_MAGIC;
1432 dev_dbg(ds1307->dev,
1433 "writing trickle charger info 0x%x to 0x%x\n",
1434 trickle_charger_setup, chip->trickle_charger_reg);
1435 regmap_write(ds1307->regmap, chip->trickle_charger_reg,
1436 trickle_charger_setup);
1437 }
1438
1439#ifdef CONFIG_OF
1440/*
1441 * For devices with no IRQ directly connected to the SoC, the RTC chip
1442 * can be forced as a wakeup source by stating that explicitly in
1443 * the device's .dts file using the "wakeup-source" boolean property.
1444 * If the "wakeup-source" property is set, don't request an IRQ.
1445 * This will guarantee the 'wakealarm' sysfs entry is available on the device,
1446 * if supported by the RTC.
1447 */
1448 if (chip->alarm && of_property_read_bool(client->dev.of_node,
1449 "wakeup-source"))
1450 ds1307_can_wakeup_device = true;
1451#endif
1452
1453 switch (ds1307->type) {
1454 case ds_1337:
1455 case ds_1339:
1456 case ds_1341:
1457 case ds_3231:
1458 /* get registers that the "rtc" read below won't read... */
1459 err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL,
1460 regs, 2);
1461 if (err) {
1462 dev_dbg(ds1307->dev, "read error %d\n", err);
1463 goto exit;
1464 }
1465
1466 /* oscillator off? turn it on, so clock can tick. */
1467 if (regs[0] & DS1337_BIT_nEOSC)
1468 regs[0] &= ~DS1337_BIT_nEOSC;
1469
1470 /*
1471 * Using IRQ or defined as wakeup-source?
1472 * Disable the square wave and both alarms.
1473 * For some variants, be sure alarms can trigger when we're
1474 * running on Vbackup (BBSQI/BBSQW)
1475 */
1476 if (want_irq || ds1307_can_wakeup_device) {
1477 regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;
1478 regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
1479 }
1480
1481 regmap_write(ds1307->regmap, DS1337_REG_CONTROL,
1482 regs[0]);
1483
1484 /* oscillator fault? clear flag, and warn */
1485 if (regs[1] & DS1337_BIT_OSF) {
1486 regmap_write(ds1307->regmap, DS1337_REG_STATUS,
1487 regs[1] & ~DS1337_BIT_OSF);
1488 dev_warn(ds1307->dev, "SET TIME!\n");
1489 }
1490 break;
1491
1492 case rx_8025:
1493 err = regmap_bulk_read(ds1307->regmap,
1494 RX8025_REG_CTRL1 << 4 | 0x08, regs, 2);
1495 if (err) {
1496 dev_dbg(ds1307->dev, "read error %d\n", err);
1497 goto exit;
1498 }
1499
1500 /* oscillator off? turn it on, so clock can tick. */
1501 if (!(regs[1] & RX8025_BIT_XST)) {
1502 regs[1] |= RX8025_BIT_XST;
1503 regmap_write(ds1307->regmap,
1504 RX8025_REG_CTRL2 << 4 | 0x08,
1505 regs[1]);
1506 dev_warn(ds1307->dev,
1507 "oscillator stop detected - SET TIME!\n");
1508 }
1509
1510 if (regs[1] & RX8025_BIT_PON) {
1511 regs[1] &= ~RX8025_BIT_PON;
1512 regmap_write(ds1307->regmap,
1513 RX8025_REG_CTRL2 << 4 | 0x08,
1514 regs[1]);
1515 dev_warn(ds1307->dev, "power-on detected\n");
1516 }
1517
1518 if (regs[1] & RX8025_BIT_VDET) {
1519 regs[1] &= ~RX8025_BIT_VDET;
1520 regmap_write(ds1307->regmap,
1521 RX8025_REG_CTRL2 << 4 | 0x08,
1522 regs[1]);
1523 dev_warn(ds1307->dev, "voltage drop detected\n");
1524 }
1525
1526 /* make sure we are running in 24hour mode */
1527 if (!(regs[0] & RX8025_BIT_2412)) {
1528 u8 hour;
1529
1530 /* switch to 24 hour mode */
1531 regmap_write(ds1307->regmap,
1532 RX8025_REG_CTRL1 << 4 | 0x08,
1533 regs[0] | RX8025_BIT_2412);
1534
1535 err = regmap_bulk_read(ds1307->regmap,
1536 RX8025_REG_CTRL1 << 4 | 0x08,
1537 regs, 2);
1538 if (err) {
1539 dev_dbg(ds1307->dev, "read error %d\n", err);
1540 goto exit;
1541 }
1542
1543 /* correct hour */
1544 hour = bcd2bin(regs[DS1307_REG_HOUR]);
1545 if (hour == 12)
1546 hour = 0;
1547 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1548 hour += 12;
1549
1550 regmap_write(ds1307->regmap,
1551 DS1307_REG_HOUR << 4 | 0x08, hour);
1552 }
1553 break;
1554 default:
1555 break;
1556 }
1557
1558read_rtc:
1559 /* read RTC registers */
1560 err = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
1561 sizeof(regs));
1562 if (err) {
1563 dev_dbg(ds1307->dev, "read error %d\n", err);
1564 goto exit;
1565 }
1566
1567 /*
1568 * minimal sanity checking; some chips (like DS1340) don't
1569 * specify the extra bits as must-be-zero, but there are
1570 * still a few values that are clearly out-of-range.
1571 */
1572 tmp = regs[DS1307_REG_SECS];
1573 switch (ds1307->type) {
1574 case ds_1307:
1575 case m41t0:
1576 case m41t00:
1577 /* clock halted? turn it on, so clock can tick. */
1578 if (tmp & DS1307_BIT_CH) {
1579 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1580 dev_warn(ds1307->dev, "SET TIME!\n");
1581 goto read_rtc;
1582 }
1583 break;
1584 case ds_1308:
1585 case ds_1338:
1586 /* clock halted? turn it on, so clock can tick. */
1587 if (tmp & DS1307_BIT_CH)
1588 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1589
1590 /* oscillator fault? clear flag, and warn */
1591 if (regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
1592 regmap_write(ds1307->regmap, DS1307_REG_CONTROL,
1593 regs[DS1307_REG_CONTROL] &
1594 ~DS1338_BIT_OSF);
1595 dev_warn(ds1307->dev, "SET TIME!\n");
1596 goto read_rtc;
1597 }
1598 break;
1599 case ds_1340:
1600 /* clock halted? turn it on, so clock can tick. */
1601 if (tmp & DS1340_BIT_nEOSC)
1602 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1603
1604 err = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp);
1605 if (err) {
1606 dev_dbg(ds1307->dev, "read error %d\n", err);
1607 goto exit;
1608 }
1609
1610 /* oscillator fault? clear flag, and warn */
1611 if (tmp & DS1340_BIT_OSF) {
1612 regmap_write(ds1307->regmap, DS1340_REG_FLAG, 0);
1613 dev_warn(ds1307->dev, "SET TIME!\n");
1614 }
1615 break;
1616 case mcp794xx:
1617 /* make sure that the backup battery is enabled */
1618 if (!(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
1619 regmap_write(ds1307->regmap, DS1307_REG_WDAY,
1620 regs[DS1307_REG_WDAY] |
1621 MCP794XX_BIT_VBATEN);
1622 }
1623
1624 /* clock halted? turn it on, so clock can tick. */
1625 if (!(tmp & MCP794XX_BIT_ST)) {
1626 regmap_write(ds1307->regmap, DS1307_REG_SECS,
1627 MCP794XX_BIT_ST);
1628 dev_warn(ds1307->dev, "SET TIME!\n");
1629 goto read_rtc;
1630 }
1631
1632 break;
1633 default:
1634 break;
1635 }
1636
1637 tmp = regs[DS1307_REG_HOUR];
1638 switch (ds1307->type) {
1639 case ds_1340:
1640 case m41t0:
1641 case m41t00:
1642 /*
1643 * NOTE: ignores century bits; fix before deploying
1644 * systems that will run through year 2100.
1645 */
1646 break;
1647 case rx_8025:
1648 break;
1649 default:
1650 if (!(tmp & DS1307_BIT_12HR))
1651 break;
1652
1653 /*
1654 * Be sure we're in 24 hour mode. Multi-master systems
1655 * take note...
1656 */
1657 tmp = bcd2bin(tmp & 0x1f);
1658 if (tmp == 12)
1659 tmp = 0;
1660 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1661 tmp += 12;
1662 regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR,
1663 bin2bcd(tmp));
1664 }
1665
1666 if (want_irq || ds1307_can_wakeup_device) {
1667 device_set_wakeup_capable(ds1307->dev, true);
1668 set_bit(HAS_ALARM, &ds1307->flags);
1669 }
1670
1671 ds1307->rtc = devm_rtc_allocate_device(ds1307->dev);
1672 if (IS_ERR(ds1307->rtc))
1673 return PTR_ERR(ds1307->rtc);
1674
1675 if (ds1307_can_wakeup_device && !want_irq) {
1676 dev_info(ds1307->dev,
1677 "'wakeup-source' is set, request for an IRQ is disabled!\n");
1678 /* We cannot support UIE mode if we do not have an IRQ line */
1679 ds1307->rtc->uie_unsupported = 1;
1680 }
1681
1682 if (want_irq) {
1683 err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL,
1684 chip->irq_handler ?: ds1307_irq,
1685 IRQF_SHARED | IRQF_ONESHOT,
1686 ds1307->name, ds1307);
1687 if (err) {
1688 client->irq = 0;
1689 device_set_wakeup_capable(ds1307->dev, false);
1690 clear_bit(HAS_ALARM, &ds1307->flags);
1691 dev_err(ds1307->dev, "unable to request IRQ!\n");
1692 } else {
1693 dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq);
1694 }
1695 }
1696
1697 ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops;
1698 err = rtc_register_device(ds1307->rtc);
1699 if (err)
1700 return err;
1701
1702 if (chip->nvram_size) {
1703 struct nvmem_config nvmem_cfg = {
1704 .name = "ds1307_nvram",
1705 .word_size = 1,
1706 .stride = 1,
1707 .size = chip->nvram_size,
1708 .reg_read = ds1307_nvram_read,
1709 .reg_write = ds1307_nvram_write,
1710 .priv = ds1307,
1711 };
1712
1713 ds1307->rtc->nvram_old_abi = true;
1714 rtc_nvmem_register(ds1307->rtc, &nvmem_cfg);
1715 }
1716
1717 ds1307_hwmon_register(ds1307);
1718 ds1307_clks_register(ds1307);
1719
1720 return 0;
1721
1722exit:
1723 return err;
1724}
1725
1726static struct i2c_driver ds1307_driver = {
1727 .driver = {
1728 .name = "rtc-ds1307",
1729 .of_match_table = of_match_ptr(ds1307_of_match),
1730 .acpi_match_table = ACPI_PTR(ds1307_acpi_ids),
1731 },
1732 .probe = ds1307_probe,
1733 .id_table = ds1307_id,
1734};
1735
1736module_i2c_driver(ds1307_driver);
1737
1738MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1739MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
4 *
5 * Copyright (C) 2005 James Chapman (ds1337 core)
6 * Copyright (C) 2006 David Brownell
7 * Copyright (C) 2009 Matthias Fuchs (rx8025 support)
8 * Copyright (C) 2012 Bertrand Achard (nvram access fixes)
9 */
10
11#include <linux/acpi.h>
12#include <linux/bcd.h>
13#include <linux/i2c.h>
14#include <linux/init.h>
15#include <linux/module.h>
16#include <linux/of_device.h>
17#include <linux/rtc/ds1307.h>
18#include <linux/rtc.h>
19#include <linux/slab.h>
20#include <linux/string.h>
21#include <linux/hwmon.h>
22#include <linux/hwmon-sysfs.h>
23#include <linux/clk-provider.h>
24#include <linux/regmap.h>
25
26/*
27 * We can't determine type by probing, but if we expect pre-Linux code
28 * to have set the chip up as a clock (turning on the oscillator and
29 * setting the date and time), Linux can ignore the non-clock features.
30 * That's a natural job for a factory or repair bench.
31 */
32enum ds_type {
33 ds_1307,
34 ds_1308,
35 ds_1337,
36 ds_1338,
37 ds_1339,
38 ds_1340,
39 ds_1341,
40 ds_1388,
41 ds_3231,
42 m41t0,
43 m41t00,
44 m41t11,
45 mcp794xx,
46 rx_8025,
47 rx_8130,
48 last_ds_type /* always last */
49 /* rs5c372 too? different address... */
50};
51
52/* RTC registers don't differ much, except for the century flag */
53#define DS1307_REG_SECS 0x00 /* 00-59 */
54# define DS1307_BIT_CH 0x80
55# define DS1340_BIT_nEOSC 0x80
56# define MCP794XX_BIT_ST 0x80
57#define DS1307_REG_MIN 0x01 /* 00-59 */
58# define M41T0_BIT_OF 0x80
59#define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
60# define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
61# define DS1307_BIT_PM 0x20 /* in REG_HOUR */
62# define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
63# define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
64#define DS1307_REG_WDAY 0x03 /* 01-07 */
65# define MCP794XX_BIT_VBATEN 0x08
66#define DS1307_REG_MDAY 0x04 /* 01-31 */
67#define DS1307_REG_MONTH 0x05 /* 01-12 */
68# define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
69#define DS1307_REG_YEAR 0x06 /* 00-99 */
70
71/*
72 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
73 * start at 7, and they differ a LOT. Only control and status matter for
74 * basic RTC date and time functionality; be careful using them.
75 */
76#define DS1307_REG_CONTROL 0x07 /* or ds1338 */
77# define DS1307_BIT_OUT 0x80
78# define DS1338_BIT_OSF 0x20
79# define DS1307_BIT_SQWE 0x10
80# define DS1307_BIT_RS1 0x02
81# define DS1307_BIT_RS0 0x01
82#define DS1337_REG_CONTROL 0x0e
83# define DS1337_BIT_nEOSC 0x80
84# define DS1339_BIT_BBSQI 0x20
85# define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
86# define DS1337_BIT_RS2 0x10
87# define DS1337_BIT_RS1 0x08
88# define DS1337_BIT_INTCN 0x04
89# define DS1337_BIT_A2IE 0x02
90# define DS1337_BIT_A1IE 0x01
91#define DS1340_REG_CONTROL 0x07
92# define DS1340_BIT_OUT 0x80
93# define DS1340_BIT_FT 0x40
94# define DS1340_BIT_CALIB_SIGN 0x20
95# define DS1340_M_CALIBRATION 0x1f
96#define DS1340_REG_FLAG 0x09
97# define DS1340_BIT_OSF 0x80
98#define DS1337_REG_STATUS 0x0f
99# define DS1337_BIT_OSF 0x80
100# define DS3231_BIT_EN32KHZ 0x08
101# define DS1337_BIT_A2I 0x02
102# define DS1337_BIT_A1I 0x01
103#define DS1339_REG_ALARM1_SECS 0x07
104
105#define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
106
107#define RX8025_REG_CTRL1 0x0e
108# define RX8025_BIT_2412 0x20
109#define RX8025_REG_CTRL2 0x0f
110# define RX8025_BIT_PON 0x10
111# define RX8025_BIT_VDET 0x40
112# define RX8025_BIT_XST 0x20
113
114#define RX8130_REG_ALARM_MIN 0x17
115#define RX8130_REG_ALARM_HOUR 0x18
116#define RX8130_REG_ALARM_WEEK_OR_DAY 0x19
117#define RX8130_REG_EXTENSION 0x1c
118#define RX8130_REG_EXTENSION_WADA BIT(3)
119#define RX8130_REG_FLAG 0x1d
120#define RX8130_REG_FLAG_VLF BIT(1)
121#define RX8130_REG_FLAG_AF BIT(3)
122#define RX8130_REG_CONTROL0 0x1e
123#define RX8130_REG_CONTROL0_AIE BIT(3)
124
125#define MCP794XX_REG_CONTROL 0x07
126# define MCP794XX_BIT_ALM0_EN 0x10
127# define MCP794XX_BIT_ALM1_EN 0x20
128#define MCP794XX_REG_ALARM0_BASE 0x0a
129#define MCP794XX_REG_ALARM0_CTRL 0x0d
130#define MCP794XX_REG_ALARM1_BASE 0x11
131#define MCP794XX_REG_ALARM1_CTRL 0x14
132# define MCP794XX_BIT_ALMX_IF BIT(3)
133# define MCP794XX_BIT_ALMX_C0 BIT(4)
134# define MCP794XX_BIT_ALMX_C1 BIT(5)
135# define MCP794XX_BIT_ALMX_C2 BIT(6)
136# define MCP794XX_BIT_ALMX_POL BIT(7)
137# define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
138 MCP794XX_BIT_ALMX_C1 | \
139 MCP794XX_BIT_ALMX_C2)
140
141#define M41TXX_REG_CONTROL 0x07
142# define M41TXX_BIT_OUT BIT(7)
143# define M41TXX_BIT_FT BIT(6)
144# define M41TXX_BIT_CALIB_SIGN BIT(5)
145# define M41TXX_M_CALIBRATION GENMASK(4, 0)
146
147/* negative offset step is -2.034ppm */
148#define M41TXX_NEG_OFFSET_STEP_PPB 2034
149/* positive offset step is +4.068ppm */
150#define M41TXX_POS_OFFSET_STEP_PPB 4068
151/* Min and max values supported with 'offset' interface by M41TXX */
152#define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB)
153#define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB)
154
155struct ds1307 {
156 enum ds_type type;
157 unsigned long flags;
158#define HAS_NVRAM 0 /* bit 0 == sysfs file active */
159#define HAS_ALARM 1 /* bit 1 == irq claimed */
160 struct device *dev;
161 struct regmap *regmap;
162 const char *name;
163 struct rtc_device *rtc;
164#ifdef CONFIG_COMMON_CLK
165 struct clk_hw clks[2];
166#endif
167};
168
169struct chip_desc {
170 unsigned alarm:1;
171 u16 nvram_offset;
172 u16 nvram_size;
173 u8 offset; /* register's offset */
174 u8 century_reg;
175 u8 century_enable_bit;
176 u8 century_bit;
177 u8 bbsqi_bit;
178 irq_handler_t irq_handler;
179 const struct rtc_class_ops *rtc_ops;
180 u16 trickle_charger_reg;
181 u8 (*do_trickle_setup)(struct ds1307 *, u32,
182 bool);
183};
184
185static const struct chip_desc chips[last_ds_type];
186
187static int ds1307_get_time(struct device *dev, struct rtc_time *t)
188{
189 struct ds1307 *ds1307 = dev_get_drvdata(dev);
190 int tmp, ret;
191 const struct chip_desc *chip = &chips[ds1307->type];
192 u8 regs[7];
193
194 if (ds1307->type == rx_8130) {
195 unsigned int regflag;
196 ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, ®flag);
197 if (ret) {
198 dev_err(dev, "%s error %d\n", "read", ret);
199 return ret;
200 }
201
202 if (regflag & RX8130_REG_FLAG_VLF) {
203 dev_warn_once(dev, "oscillator failed, set time!\n");
204 return -EINVAL;
205 }
206 }
207
208 /* read the RTC date and time registers all at once */
209 ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
210 sizeof(regs));
211 if (ret) {
212 dev_err(dev, "%s error %d\n", "read", ret);
213 return ret;
214 }
215
216 dev_dbg(dev, "%s: %7ph\n", "read", regs);
217
218 /* if oscillator fail bit is set, no data can be trusted */
219 if (ds1307->type == m41t0 &&
220 regs[DS1307_REG_MIN] & M41T0_BIT_OF) {
221 dev_warn_once(dev, "oscillator failed, set time!\n");
222 return -EINVAL;
223 }
224
225 tmp = regs[DS1307_REG_SECS];
226 switch (ds1307->type) {
227 case ds_1307:
228 case m41t0:
229 case m41t00:
230 case m41t11:
231 if (tmp & DS1307_BIT_CH)
232 return -EINVAL;
233 break;
234 case ds_1308:
235 case ds_1338:
236 if (tmp & DS1307_BIT_CH)
237 return -EINVAL;
238
239 ret = regmap_read(ds1307->regmap, DS1307_REG_CONTROL, &tmp);
240 if (ret)
241 return ret;
242 if (tmp & DS1338_BIT_OSF)
243 return -EINVAL;
244 break;
245 case ds_1340:
246 if (tmp & DS1340_BIT_nEOSC)
247 return -EINVAL;
248
249 ret = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp);
250 if (ret)
251 return ret;
252 if (tmp & DS1340_BIT_OSF)
253 return -EINVAL;
254 break;
255 case mcp794xx:
256 if (!(tmp & MCP794XX_BIT_ST))
257 return -EINVAL;
258
259 break;
260 default:
261 break;
262 }
263
264 t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f);
265 t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f);
266 tmp = regs[DS1307_REG_HOUR] & 0x3f;
267 t->tm_hour = bcd2bin(tmp);
268 t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1;
269 t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f);
270 tmp = regs[DS1307_REG_MONTH] & 0x1f;
271 t->tm_mon = bcd2bin(tmp) - 1;
272 t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100;
273
274 if (regs[chip->century_reg] & chip->century_bit &&
275 IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY))
276 t->tm_year += 100;
277
278 dev_dbg(dev, "%s secs=%d, mins=%d, "
279 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
280 "read", t->tm_sec, t->tm_min,
281 t->tm_hour, t->tm_mday,
282 t->tm_mon, t->tm_year, t->tm_wday);
283
284 return 0;
285}
286
287static int ds1307_set_time(struct device *dev, struct rtc_time *t)
288{
289 struct ds1307 *ds1307 = dev_get_drvdata(dev);
290 const struct chip_desc *chip = &chips[ds1307->type];
291 int result;
292 int tmp;
293 u8 regs[7];
294
295 dev_dbg(dev, "%s secs=%d, mins=%d, "
296 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
297 "write", t->tm_sec, t->tm_min,
298 t->tm_hour, t->tm_mday,
299 t->tm_mon, t->tm_year, t->tm_wday);
300
301 if (t->tm_year < 100)
302 return -EINVAL;
303
304#ifdef CONFIG_RTC_DRV_DS1307_CENTURY
305 if (t->tm_year > (chip->century_bit ? 299 : 199))
306 return -EINVAL;
307#else
308 if (t->tm_year > 199)
309 return -EINVAL;
310#endif
311
312 regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
313 regs[DS1307_REG_MIN] = bin2bcd(t->tm_min);
314 regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
315 regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
316 regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
317 regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
318
319 /* assume 20YY not 19YY */
320 tmp = t->tm_year - 100;
321 regs[DS1307_REG_YEAR] = bin2bcd(tmp);
322
323 if (chip->century_enable_bit)
324 regs[chip->century_reg] |= chip->century_enable_bit;
325 if (t->tm_year > 199 && chip->century_bit)
326 regs[chip->century_reg] |= chip->century_bit;
327
328 switch (ds1307->type) {
329 case ds_1308:
330 case ds_1338:
331 regmap_update_bits(ds1307->regmap, DS1307_REG_CONTROL,
332 DS1338_BIT_OSF, 0);
333 break;
334 case ds_1340:
335 regmap_update_bits(ds1307->regmap, DS1340_REG_FLAG,
336 DS1340_BIT_OSF, 0);
337 break;
338 case mcp794xx:
339 /*
340 * these bits were cleared when preparing the date/time
341 * values and need to be set again before writing the
342 * regsfer out to the device.
343 */
344 regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
345 regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
346 break;
347 default:
348 break;
349 }
350
351 dev_dbg(dev, "%s: %7ph\n", "write", regs);
352
353 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,
354 sizeof(regs));
355 if (result) {
356 dev_err(dev, "%s error %d\n", "write", result);
357 return result;
358 }
359
360 if (ds1307->type == rx_8130) {
361 /* clear Voltage Loss Flag as data is available now */
362 result = regmap_write(ds1307->regmap, RX8130_REG_FLAG,
363 ~(u8)RX8130_REG_FLAG_VLF);
364 if (result) {
365 dev_err(dev, "%s error %d\n", "write", result);
366 return result;
367 }
368 }
369
370 return 0;
371}
372
373static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
374{
375 struct ds1307 *ds1307 = dev_get_drvdata(dev);
376 int ret;
377 u8 regs[9];
378
379 if (!test_bit(HAS_ALARM, &ds1307->flags))
380 return -EINVAL;
381
382 /* read all ALARM1, ALARM2, and status registers at once */
383 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS,
384 regs, sizeof(regs));
385 if (ret) {
386 dev_err(dev, "%s error %d\n", "alarm read", ret);
387 return ret;
388 }
389
390 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
391 ®s[0], ®s[4], ®s[7]);
392
393 /*
394 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
395 * and that all four fields are checked matches
396 */
397 t->time.tm_sec = bcd2bin(regs[0] & 0x7f);
398 t->time.tm_min = bcd2bin(regs[1] & 0x7f);
399 t->time.tm_hour = bcd2bin(regs[2] & 0x3f);
400 t->time.tm_mday = bcd2bin(regs[3] & 0x3f);
401
402 /* ... and status */
403 t->enabled = !!(regs[7] & DS1337_BIT_A1IE);
404 t->pending = !!(regs[8] & DS1337_BIT_A1I);
405
406 dev_dbg(dev, "%s secs=%d, mins=%d, "
407 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
408 "alarm read", t->time.tm_sec, t->time.tm_min,
409 t->time.tm_hour, t->time.tm_mday,
410 t->enabled, t->pending);
411
412 return 0;
413}
414
415static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
416{
417 struct ds1307 *ds1307 = dev_get_drvdata(dev);
418 unsigned char regs[9];
419 u8 control, status;
420 int ret;
421
422 if (!test_bit(HAS_ALARM, &ds1307->flags))
423 return -EINVAL;
424
425 dev_dbg(dev, "%s secs=%d, mins=%d, "
426 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
427 "alarm set", t->time.tm_sec, t->time.tm_min,
428 t->time.tm_hour, t->time.tm_mday,
429 t->enabled, t->pending);
430
431 /* read current status of both alarms and the chip */
432 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
433 sizeof(regs));
434 if (ret) {
435 dev_err(dev, "%s error %d\n", "alarm write", ret);
436 return ret;
437 }
438 control = regs[7];
439 status = regs[8];
440
441 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
442 ®s[0], ®s[4], control, status);
443
444 /* set ALARM1, using 24 hour and day-of-month modes */
445 regs[0] = bin2bcd(t->time.tm_sec);
446 regs[1] = bin2bcd(t->time.tm_min);
447 regs[2] = bin2bcd(t->time.tm_hour);
448 regs[3] = bin2bcd(t->time.tm_mday);
449
450 /* set ALARM2 to non-garbage */
451 regs[4] = 0;
452 regs[5] = 0;
453 regs[6] = 0;
454
455 /* disable alarms */
456 regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
457 regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
458
459 ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
460 sizeof(regs));
461 if (ret) {
462 dev_err(dev, "can't set alarm time\n");
463 return ret;
464 }
465
466 /* optionally enable ALARM1 */
467 if (t->enabled) {
468 dev_dbg(dev, "alarm IRQ armed\n");
469 regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
470 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]);
471 }
472
473 return 0;
474}
475
476static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
477{
478 struct ds1307 *ds1307 = dev_get_drvdata(dev);
479
480 if (!test_bit(HAS_ALARM, &ds1307->flags))
481 return -ENOTTY;
482
483 return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
484 DS1337_BIT_A1IE,
485 enabled ? DS1337_BIT_A1IE : 0);
486}
487
488static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode)
489{
490 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
491 DS1307_TRICKLE_CHARGER_NO_DIODE;
492
493 switch (ohms) {
494 case 250:
495 setup |= DS1307_TRICKLE_CHARGER_250_OHM;
496 break;
497 case 2000:
498 setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
499 break;
500 case 4000:
501 setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
502 break;
503 default:
504 dev_warn(ds1307->dev,
505 "Unsupported ohm value %u in dt\n", ohms);
506 return 0;
507 }
508 return setup;
509}
510
511static irqreturn_t rx8130_irq(int irq, void *dev_id)
512{
513 struct ds1307 *ds1307 = dev_id;
514 struct mutex *lock = &ds1307->rtc->ops_lock;
515 u8 ctl[3];
516 int ret;
517
518 mutex_lock(lock);
519
520 /* Read control registers. */
521 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
522 sizeof(ctl));
523 if (ret < 0)
524 goto out;
525 if (!(ctl[1] & RX8130_REG_FLAG_AF))
526 goto out;
527 ctl[1] &= ~RX8130_REG_FLAG_AF;
528 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
529
530 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
531 sizeof(ctl));
532 if (ret < 0)
533 goto out;
534
535 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
536
537out:
538 mutex_unlock(lock);
539
540 return IRQ_HANDLED;
541}
542
543static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t)
544{
545 struct ds1307 *ds1307 = dev_get_drvdata(dev);
546 u8 ald[3], ctl[3];
547 int ret;
548
549 if (!test_bit(HAS_ALARM, &ds1307->flags))
550 return -EINVAL;
551
552 /* Read alarm registers. */
553 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
554 sizeof(ald));
555 if (ret < 0)
556 return ret;
557
558 /* Read control registers. */
559 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
560 sizeof(ctl));
561 if (ret < 0)
562 return ret;
563
564 t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE);
565 t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF);
566
567 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
568 t->time.tm_sec = -1;
569 t->time.tm_min = bcd2bin(ald[0] & 0x7f);
570 t->time.tm_hour = bcd2bin(ald[1] & 0x7f);
571 t->time.tm_wday = -1;
572 t->time.tm_mday = bcd2bin(ald[2] & 0x7f);
573 t->time.tm_mon = -1;
574 t->time.tm_year = -1;
575 t->time.tm_yday = -1;
576 t->time.tm_isdst = -1;
577
578 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n",
579 __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
580 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled);
581
582 return 0;
583}
584
585static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
586{
587 struct ds1307 *ds1307 = dev_get_drvdata(dev);
588 u8 ald[3], ctl[3];
589 int ret;
590
591 if (!test_bit(HAS_ALARM, &ds1307->flags))
592 return -EINVAL;
593
594 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
595 "enabled=%d pending=%d\n", __func__,
596 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
597 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
598 t->enabled, t->pending);
599
600 /* Read control registers. */
601 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
602 sizeof(ctl));
603 if (ret < 0)
604 return ret;
605
606 ctl[0] &= RX8130_REG_EXTENSION_WADA;
607 ctl[1] &= ~RX8130_REG_FLAG_AF;
608 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
609
610 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
611 sizeof(ctl));
612 if (ret < 0)
613 return ret;
614
615 /* Hardware alarm precision is 1 minute! */
616 ald[0] = bin2bcd(t->time.tm_min);
617 ald[1] = bin2bcd(t->time.tm_hour);
618 ald[2] = bin2bcd(t->time.tm_mday);
619
620 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
621 sizeof(ald));
622 if (ret < 0)
623 return ret;
624
625 if (!t->enabled)
626 return 0;
627
628 ctl[2] |= RX8130_REG_CONTROL0_AIE;
629
630 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]);
631}
632
633static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
634{
635 struct ds1307 *ds1307 = dev_get_drvdata(dev);
636 int ret, reg;
637
638 if (!test_bit(HAS_ALARM, &ds1307->flags))
639 return -EINVAL;
640
641 ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®);
642 if (ret < 0)
643 return ret;
644
645 if (enabled)
646 reg |= RX8130_REG_CONTROL0_AIE;
647 else
648 reg &= ~RX8130_REG_CONTROL0_AIE;
649
650 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg);
651}
652
653static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
654{
655 struct ds1307 *ds1307 = dev_id;
656 struct mutex *lock = &ds1307->rtc->ops_lock;
657 int reg, ret;
658
659 mutex_lock(lock);
660
661 /* Check and clear alarm 0 interrupt flag. */
662 ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®);
663 if (ret)
664 goto out;
665 if (!(reg & MCP794XX_BIT_ALMX_IF))
666 goto out;
667 reg &= ~MCP794XX_BIT_ALMX_IF;
668 ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg);
669 if (ret)
670 goto out;
671
672 /* Disable alarm 0. */
673 ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
674 MCP794XX_BIT_ALM0_EN, 0);
675 if (ret)
676 goto out;
677
678 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
679
680out:
681 mutex_unlock(lock);
682
683 return IRQ_HANDLED;
684}
685
686static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)
687{
688 struct ds1307 *ds1307 = dev_get_drvdata(dev);
689 u8 regs[10];
690 int ret;
691
692 if (!test_bit(HAS_ALARM, &ds1307->flags))
693 return -EINVAL;
694
695 /* Read control and alarm 0 registers. */
696 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
697 sizeof(regs));
698 if (ret)
699 return ret;
700
701 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);
702
703 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
704 t->time.tm_sec = bcd2bin(regs[3] & 0x7f);
705 t->time.tm_min = bcd2bin(regs[4] & 0x7f);
706 t->time.tm_hour = bcd2bin(regs[5] & 0x3f);
707 t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1;
708 t->time.tm_mday = bcd2bin(regs[7] & 0x3f);
709 t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1;
710 t->time.tm_year = -1;
711 t->time.tm_yday = -1;
712 t->time.tm_isdst = -1;
713
714 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
715 "enabled=%d polarity=%d irq=%d match=%lu\n", __func__,
716 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
717 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
718 !!(regs[6] & MCP794XX_BIT_ALMX_POL),
719 !!(regs[6] & MCP794XX_BIT_ALMX_IF),
720 (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
721
722 return 0;
723}
724
725/*
726 * We may have a random RTC weekday, therefore calculate alarm weekday based
727 * on current weekday we read from the RTC timekeeping regs
728 */
729static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm)
730{
731 struct rtc_time tm_now;
732 int days_now, days_alarm, ret;
733
734 ret = ds1307_get_time(dev, &tm_now);
735 if (ret)
736 return ret;
737
738 days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60);
739 days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60);
740
741 return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1;
742}
743
744static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
745{
746 struct ds1307 *ds1307 = dev_get_drvdata(dev);
747 unsigned char regs[10];
748 int wday, ret;
749
750 if (!test_bit(HAS_ALARM, &ds1307->flags))
751 return -EINVAL;
752
753 wday = mcp794xx_alm_weekday(dev, &t->time);
754 if (wday < 0)
755 return wday;
756
757 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
758 "enabled=%d pending=%d\n", __func__,
759 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
760 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
761 t->enabled, t->pending);
762
763 /* Read control and alarm 0 registers. */
764 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
765 sizeof(regs));
766 if (ret)
767 return ret;
768
769 /* Set alarm 0, using 24-hour and day-of-month modes. */
770 regs[3] = bin2bcd(t->time.tm_sec);
771 regs[4] = bin2bcd(t->time.tm_min);
772 regs[5] = bin2bcd(t->time.tm_hour);
773 regs[6] = wday;
774 regs[7] = bin2bcd(t->time.tm_mday);
775 regs[8] = bin2bcd(t->time.tm_mon + 1);
776
777 /* Clear the alarm 0 interrupt flag. */
778 regs[6] &= ~MCP794XX_BIT_ALMX_IF;
779 /* Set alarm match: second, minute, hour, day, date, month. */
780 regs[6] |= MCP794XX_MSK_ALMX_MATCH;
781 /* Disable interrupt. We will not enable until completely programmed */
782 regs[0] &= ~MCP794XX_BIT_ALM0_EN;
783
784 ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
785 sizeof(regs));
786 if (ret)
787 return ret;
788
789 if (!t->enabled)
790 return 0;
791 regs[0] |= MCP794XX_BIT_ALM0_EN;
792 return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]);
793}
794
795static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
796{
797 struct ds1307 *ds1307 = dev_get_drvdata(dev);
798
799 if (!test_bit(HAS_ALARM, &ds1307->flags))
800 return -EINVAL;
801
802 return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
803 MCP794XX_BIT_ALM0_EN,
804 enabled ? MCP794XX_BIT_ALM0_EN : 0);
805}
806
807static int m41txx_rtc_read_offset(struct device *dev, long *offset)
808{
809 struct ds1307 *ds1307 = dev_get_drvdata(dev);
810 unsigned int ctrl_reg;
811 u8 val;
812
813 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
814
815 val = ctrl_reg & M41TXX_M_CALIBRATION;
816
817 /* check if positive */
818 if (ctrl_reg & M41TXX_BIT_CALIB_SIGN)
819 *offset = (val * M41TXX_POS_OFFSET_STEP_PPB);
820 else
821 *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB);
822
823 return 0;
824}
825
826static int m41txx_rtc_set_offset(struct device *dev, long offset)
827{
828 struct ds1307 *ds1307 = dev_get_drvdata(dev);
829 unsigned int ctrl_reg;
830
831 if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET))
832 return -ERANGE;
833
834 if (offset >= 0) {
835 ctrl_reg = DIV_ROUND_CLOSEST(offset,
836 M41TXX_POS_OFFSET_STEP_PPB);
837 ctrl_reg |= M41TXX_BIT_CALIB_SIGN;
838 } else {
839 ctrl_reg = DIV_ROUND_CLOSEST(abs(offset),
840 M41TXX_NEG_OFFSET_STEP_PPB);
841 }
842
843 return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL,
844 M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN,
845 ctrl_reg);
846}
847
848static const struct rtc_class_ops rx8130_rtc_ops = {
849 .read_time = ds1307_get_time,
850 .set_time = ds1307_set_time,
851 .read_alarm = rx8130_read_alarm,
852 .set_alarm = rx8130_set_alarm,
853 .alarm_irq_enable = rx8130_alarm_irq_enable,
854};
855
856static const struct rtc_class_ops mcp794xx_rtc_ops = {
857 .read_time = ds1307_get_time,
858 .set_time = ds1307_set_time,
859 .read_alarm = mcp794xx_read_alarm,
860 .set_alarm = mcp794xx_set_alarm,
861 .alarm_irq_enable = mcp794xx_alarm_irq_enable,
862};
863
864static const struct rtc_class_ops m41txx_rtc_ops = {
865 .read_time = ds1307_get_time,
866 .set_time = ds1307_set_time,
867 .read_alarm = ds1337_read_alarm,
868 .set_alarm = ds1337_set_alarm,
869 .alarm_irq_enable = ds1307_alarm_irq_enable,
870 .read_offset = m41txx_rtc_read_offset,
871 .set_offset = m41txx_rtc_set_offset,
872};
873
874static const struct chip_desc chips[last_ds_type] = {
875 [ds_1307] = {
876 .nvram_offset = 8,
877 .nvram_size = 56,
878 },
879 [ds_1308] = {
880 .nvram_offset = 8,
881 .nvram_size = 56,
882 },
883 [ds_1337] = {
884 .alarm = 1,
885 .century_reg = DS1307_REG_MONTH,
886 .century_bit = DS1337_BIT_CENTURY,
887 },
888 [ds_1338] = {
889 .nvram_offset = 8,
890 .nvram_size = 56,
891 },
892 [ds_1339] = {
893 .alarm = 1,
894 .century_reg = DS1307_REG_MONTH,
895 .century_bit = DS1337_BIT_CENTURY,
896 .bbsqi_bit = DS1339_BIT_BBSQI,
897 .trickle_charger_reg = 0x10,
898 .do_trickle_setup = &do_trickle_setup_ds1339,
899 },
900 [ds_1340] = {
901 .century_reg = DS1307_REG_HOUR,
902 .century_enable_bit = DS1340_BIT_CENTURY_EN,
903 .century_bit = DS1340_BIT_CENTURY,
904 .do_trickle_setup = &do_trickle_setup_ds1339,
905 .trickle_charger_reg = 0x08,
906 },
907 [ds_1341] = {
908 .century_reg = DS1307_REG_MONTH,
909 .century_bit = DS1337_BIT_CENTURY,
910 },
911 [ds_1388] = {
912 .offset = 1,
913 .trickle_charger_reg = 0x0a,
914 },
915 [ds_3231] = {
916 .alarm = 1,
917 .century_reg = DS1307_REG_MONTH,
918 .century_bit = DS1337_BIT_CENTURY,
919 .bbsqi_bit = DS3231_BIT_BBSQW,
920 },
921 [rx_8130] = {
922 .alarm = 1,
923 /* this is battery backed SRAM */
924 .nvram_offset = 0x20,
925 .nvram_size = 4, /* 32bit (4 word x 8 bit) */
926 .offset = 0x10,
927 .irq_handler = rx8130_irq,
928 .rtc_ops = &rx8130_rtc_ops,
929 },
930 [m41t0] = {
931 .rtc_ops = &m41txx_rtc_ops,
932 },
933 [m41t00] = {
934 .rtc_ops = &m41txx_rtc_ops,
935 },
936 [m41t11] = {
937 /* this is battery backed SRAM */
938 .nvram_offset = 8,
939 .nvram_size = 56,
940 .rtc_ops = &m41txx_rtc_ops,
941 },
942 [mcp794xx] = {
943 .alarm = 1,
944 /* this is battery backed SRAM */
945 .nvram_offset = 0x20,
946 .nvram_size = 0x40,
947 .irq_handler = mcp794xx_irq,
948 .rtc_ops = &mcp794xx_rtc_ops,
949 },
950};
951
952static const struct i2c_device_id ds1307_id[] = {
953 { "ds1307", ds_1307 },
954 { "ds1308", ds_1308 },
955 { "ds1337", ds_1337 },
956 { "ds1338", ds_1338 },
957 { "ds1339", ds_1339 },
958 { "ds1388", ds_1388 },
959 { "ds1340", ds_1340 },
960 { "ds1341", ds_1341 },
961 { "ds3231", ds_3231 },
962 { "m41t0", m41t0 },
963 { "m41t00", m41t00 },
964 { "m41t11", m41t11 },
965 { "mcp7940x", mcp794xx },
966 { "mcp7941x", mcp794xx },
967 { "pt7c4338", ds_1307 },
968 { "rx8025", rx_8025 },
969 { "isl12057", ds_1337 },
970 { "rx8130", rx_8130 },
971 { }
972};
973MODULE_DEVICE_TABLE(i2c, ds1307_id);
974
975#ifdef CONFIG_OF
976static const struct of_device_id ds1307_of_match[] = {
977 {
978 .compatible = "dallas,ds1307",
979 .data = (void *)ds_1307
980 },
981 {
982 .compatible = "dallas,ds1308",
983 .data = (void *)ds_1308
984 },
985 {
986 .compatible = "dallas,ds1337",
987 .data = (void *)ds_1337
988 },
989 {
990 .compatible = "dallas,ds1338",
991 .data = (void *)ds_1338
992 },
993 {
994 .compatible = "dallas,ds1339",
995 .data = (void *)ds_1339
996 },
997 {
998 .compatible = "dallas,ds1388",
999 .data = (void *)ds_1388
1000 },
1001 {
1002 .compatible = "dallas,ds1340",
1003 .data = (void *)ds_1340
1004 },
1005 {
1006 .compatible = "dallas,ds1341",
1007 .data = (void *)ds_1341
1008 },
1009 {
1010 .compatible = "maxim,ds3231",
1011 .data = (void *)ds_3231
1012 },
1013 {
1014 .compatible = "st,m41t0",
1015 .data = (void *)m41t0
1016 },
1017 {
1018 .compatible = "st,m41t00",
1019 .data = (void *)m41t00
1020 },
1021 {
1022 .compatible = "st,m41t11",
1023 .data = (void *)m41t11
1024 },
1025 {
1026 .compatible = "microchip,mcp7940x",
1027 .data = (void *)mcp794xx
1028 },
1029 {
1030 .compatible = "microchip,mcp7941x",
1031 .data = (void *)mcp794xx
1032 },
1033 {
1034 .compatible = "pericom,pt7c4338",
1035 .data = (void *)ds_1307
1036 },
1037 {
1038 .compatible = "epson,rx8025",
1039 .data = (void *)rx_8025
1040 },
1041 {
1042 .compatible = "isil,isl12057",
1043 .data = (void *)ds_1337
1044 },
1045 {
1046 .compatible = "epson,rx8130",
1047 .data = (void *)rx_8130
1048 },
1049 { }
1050};
1051MODULE_DEVICE_TABLE(of, ds1307_of_match);
1052#endif
1053
1054#ifdef CONFIG_ACPI
1055static const struct acpi_device_id ds1307_acpi_ids[] = {
1056 { .id = "DS1307", .driver_data = ds_1307 },
1057 { .id = "DS1308", .driver_data = ds_1308 },
1058 { .id = "DS1337", .driver_data = ds_1337 },
1059 { .id = "DS1338", .driver_data = ds_1338 },
1060 { .id = "DS1339", .driver_data = ds_1339 },
1061 { .id = "DS1388", .driver_data = ds_1388 },
1062 { .id = "DS1340", .driver_data = ds_1340 },
1063 { .id = "DS1341", .driver_data = ds_1341 },
1064 { .id = "DS3231", .driver_data = ds_3231 },
1065 { .id = "M41T0", .driver_data = m41t0 },
1066 { .id = "M41T00", .driver_data = m41t00 },
1067 { .id = "M41T11", .driver_data = m41t11 },
1068 { .id = "MCP7940X", .driver_data = mcp794xx },
1069 { .id = "MCP7941X", .driver_data = mcp794xx },
1070 { .id = "PT7C4338", .driver_data = ds_1307 },
1071 { .id = "RX8025", .driver_data = rx_8025 },
1072 { .id = "ISL12057", .driver_data = ds_1337 },
1073 { .id = "RX8130", .driver_data = rx_8130 },
1074 { }
1075};
1076MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
1077#endif
1078
1079/*
1080 * The ds1337 and ds1339 both have two alarms, but we only use the first
1081 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
1082 * signal; ds1339 chips have only one alarm signal.
1083 */
1084static irqreturn_t ds1307_irq(int irq, void *dev_id)
1085{
1086 struct ds1307 *ds1307 = dev_id;
1087 struct mutex *lock = &ds1307->rtc->ops_lock;
1088 int stat, ret;
1089
1090 mutex_lock(lock);
1091 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
1092 if (ret)
1093 goto out;
1094
1095 if (stat & DS1337_BIT_A1I) {
1096 stat &= ~DS1337_BIT_A1I;
1097 regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
1098
1099 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1100 DS1337_BIT_A1IE, 0);
1101 if (ret)
1102 goto out;
1103
1104 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
1105 }
1106
1107out:
1108 mutex_unlock(lock);
1109
1110 return IRQ_HANDLED;
1111}
1112
1113/*----------------------------------------------------------------------*/
1114
1115static const struct rtc_class_ops ds13xx_rtc_ops = {
1116 .read_time = ds1307_get_time,
1117 .set_time = ds1307_set_time,
1118 .read_alarm = ds1337_read_alarm,
1119 .set_alarm = ds1337_set_alarm,
1120 .alarm_irq_enable = ds1307_alarm_irq_enable,
1121};
1122
1123static ssize_t frequency_test_store(struct device *dev,
1124 struct device_attribute *attr,
1125 const char *buf, size_t count)
1126{
1127 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1128 bool freq_test_en;
1129 int ret;
1130
1131 ret = kstrtobool(buf, &freq_test_en);
1132 if (ret) {
1133 dev_err(dev, "Failed to store RTC Frequency Test attribute\n");
1134 return ret;
1135 }
1136
1137 regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT,
1138 freq_test_en ? M41TXX_BIT_FT : 0);
1139
1140 return count;
1141}
1142
1143static ssize_t frequency_test_show(struct device *dev,
1144 struct device_attribute *attr,
1145 char *buf)
1146{
1147 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1148 unsigned int ctrl_reg;
1149
1150 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
1151
1152 return scnprintf(buf, PAGE_SIZE, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" :
1153 "off\n");
1154}
1155
1156static DEVICE_ATTR_RW(frequency_test);
1157
1158static struct attribute *rtc_freq_test_attrs[] = {
1159 &dev_attr_frequency_test.attr,
1160 NULL,
1161};
1162
1163static const struct attribute_group rtc_freq_test_attr_group = {
1164 .attrs = rtc_freq_test_attrs,
1165};
1166
1167static int ds1307_add_frequency_test(struct ds1307 *ds1307)
1168{
1169 int err;
1170
1171 switch (ds1307->type) {
1172 case m41t0:
1173 case m41t00:
1174 case m41t11:
1175 err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group);
1176 if (err)
1177 return err;
1178 break;
1179 default:
1180 break;
1181 }
1182
1183 return 0;
1184}
1185
1186/*----------------------------------------------------------------------*/
1187
1188static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,
1189 size_t bytes)
1190{
1191 struct ds1307 *ds1307 = priv;
1192 const struct chip_desc *chip = &chips[ds1307->type];
1193
1194 return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset,
1195 val, bytes);
1196}
1197
1198static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
1199 size_t bytes)
1200{
1201 struct ds1307 *ds1307 = priv;
1202 const struct chip_desc *chip = &chips[ds1307->type];
1203
1204 return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset,
1205 val, bytes);
1206}
1207
1208/*----------------------------------------------------------------------*/
1209
1210static u8 ds1307_trickle_init(struct ds1307 *ds1307,
1211 const struct chip_desc *chip)
1212{
1213 u32 ohms;
1214 bool diode = true;
1215
1216 if (!chip->do_trickle_setup)
1217 return 0;
1218
1219 if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms",
1220 &ohms))
1221 return 0;
1222
1223 if (device_property_read_bool(ds1307->dev, "trickle-diode-disable"))
1224 diode = false;
1225
1226 return chip->do_trickle_setup(ds1307, ohms, diode);
1227}
1228
1229/*----------------------------------------------------------------------*/
1230
1231#if IS_REACHABLE(CONFIG_HWMON)
1232
1233/*
1234 * Temperature sensor support for ds3231 devices.
1235 */
1236
1237#define DS3231_REG_TEMPERATURE 0x11
1238
1239/*
1240 * A user-initiated temperature conversion is not started by this function,
1241 * so the temperature is updated once every 64 seconds.
1242 */
1243static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)
1244{
1245 struct ds1307 *ds1307 = dev_get_drvdata(dev);
1246 u8 temp_buf[2];
1247 s16 temp;
1248 int ret;
1249
1250 ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE,
1251 temp_buf, sizeof(temp_buf));
1252 if (ret)
1253 return ret;
1254 /*
1255 * Temperature is represented as a 10-bit code with a resolution of
1256 * 0.25 degree celsius and encoded in two's complement format.
1257 */
1258 temp = (temp_buf[0] << 8) | temp_buf[1];
1259 temp >>= 6;
1260 *mC = temp * 250;
1261
1262 return 0;
1263}
1264
1265static ssize_t ds3231_hwmon_show_temp(struct device *dev,
1266 struct device_attribute *attr, char *buf)
1267{
1268 int ret;
1269 s32 temp;
1270
1271 ret = ds3231_hwmon_read_temp(dev, &temp);
1272 if (ret)
1273 return ret;
1274
1275 return sprintf(buf, "%d\n", temp);
1276}
1277static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp,
1278 NULL, 0);
1279
1280static struct attribute *ds3231_hwmon_attrs[] = {
1281 &sensor_dev_attr_temp1_input.dev_attr.attr,
1282 NULL,
1283};
1284ATTRIBUTE_GROUPS(ds3231_hwmon);
1285
1286static void ds1307_hwmon_register(struct ds1307 *ds1307)
1287{
1288 struct device *dev;
1289
1290 if (ds1307->type != ds_3231)
1291 return;
1292
1293 dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name,
1294 ds1307,
1295 ds3231_hwmon_groups);
1296 if (IS_ERR(dev)) {
1297 dev_warn(ds1307->dev, "unable to register hwmon device %ld\n",
1298 PTR_ERR(dev));
1299 }
1300}
1301
1302#else
1303
1304static void ds1307_hwmon_register(struct ds1307 *ds1307)
1305{
1306}
1307
1308#endif /* CONFIG_RTC_DRV_DS1307_HWMON */
1309
1310/*----------------------------------------------------------------------*/
1311
1312/*
1313 * Square-wave output support for DS3231
1314 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf
1315 */
1316#ifdef CONFIG_COMMON_CLK
1317
1318enum {
1319 DS3231_CLK_SQW = 0,
1320 DS3231_CLK_32KHZ,
1321};
1322
1323#define clk_sqw_to_ds1307(clk) \
1324 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW])
1325#define clk_32khz_to_ds1307(clk) \
1326 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ])
1327
1328static int ds3231_clk_sqw_rates[] = {
1329 1,
1330 1024,
1331 4096,
1332 8192,
1333};
1334
1335static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value)
1336{
1337 struct mutex *lock = &ds1307->rtc->ops_lock;
1338 int ret;
1339
1340 mutex_lock(lock);
1341 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1342 mask, value);
1343 mutex_unlock(lock);
1344
1345 return ret;
1346}
1347
1348static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw,
1349 unsigned long parent_rate)
1350{
1351 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1352 int control, ret;
1353 int rate_sel = 0;
1354
1355 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1356 if (ret)
1357 return ret;
1358 if (control & DS1337_BIT_RS1)
1359 rate_sel += 1;
1360 if (control & DS1337_BIT_RS2)
1361 rate_sel += 2;
1362
1363 return ds3231_clk_sqw_rates[rate_sel];
1364}
1365
1366static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
1367 unsigned long *prate)
1368{
1369 int i;
1370
1371 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) {
1372 if (ds3231_clk_sqw_rates[i] <= rate)
1373 return ds3231_clk_sqw_rates[i];
1374 }
1375
1376 return 0;
1377}
1378
1379static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
1380 unsigned long parent_rate)
1381{
1382 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1383 int control = 0;
1384 int rate_sel;
1385
1386 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates);
1387 rate_sel++) {
1388 if (ds3231_clk_sqw_rates[rate_sel] == rate)
1389 break;
1390 }
1391
1392 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates))
1393 return -EINVAL;
1394
1395 if (rate_sel & 1)
1396 control |= DS1337_BIT_RS1;
1397 if (rate_sel & 2)
1398 control |= DS1337_BIT_RS2;
1399
1400 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2,
1401 control);
1402}
1403
1404static int ds3231_clk_sqw_prepare(struct clk_hw *hw)
1405{
1406 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1407
1408 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0);
1409}
1410
1411static void ds3231_clk_sqw_unprepare(struct clk_hw *hw)
1412{
1413 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1414
1415 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN);
1416}
1417
1418static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw)
1419{
1420 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1421 int control, ret;
1422
1423 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1424 if (ret)
1425 return ret;
1426
1427 return !(control & DS1337_BIT_INTCN);
1428}
1429
1430static const struct clk_ops ds3231_clk_sqw_ops = {
1431 .prepare = ds3231_clk_sqw_prepare,
1432 .unprepare = ds3231_clk_sqw_unprepare,
1433 .is_prepared = ds3231_clk_sqw_is_prepared,
1434 .recalc_rate = ds3231_clk_sqw_recalc_rate,
1435 .round_rate = ds3231_clk_sqw_round_rate,
1436 .set_rate = ds3231_clk_sqw_set_rate,
1437};
1438
1439static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw,
1440 unsigned long parent_rate)
1441{
1442 return 32768;
1443}
1444
1445static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable)
1446{
1447 struct mutex *lock = &ds1307->rtc->ops_lock;
1448 int ret;
1449
1450 mutex_lock(lock);
1451 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS,
1452 DS3231_BIT_EN32KHZ,
1453 enable ? DS3231_BIT_EN32KHZ : 0);
1454 mutex_unlock(lock);
1455
1456 return ret;
1457}
1458
1459static int ds3231_clk_32khz_prepare(struct clk_hw *hw)
1460{
1461 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1462
1463 return ds3231_clk_32khz_control(ds1307, true);
1464}
1465
1466static void ds3231_clk_32khz_unprepare(struct clk_hw *hw)
1467{
1468 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1469
1470 ds3231_clk_32khz_control(ds1307, false);
1471}
1472
1473static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw)
1474{
1475 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1476 int status, ret;
1477
1478 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status);
1479 if (ret)
1480 return ret;
1481
1482 return !!(status & DS3231_BIT_EN32KHZ);
1483}
1484
1485static const struct clk_ops ds3231_clk_32khz_ops = {
1486 .prepare = ds3231_clk_32khz_prepare,
1487 .unprepare = ds3231_clk_32khz_unprepare,
1488 .is_prepared = ds3231_clk_32khz_is_prepared,
1489 .recalc_rate = ds3231_clk_32khz_recalc_rate,
1490};
1491
1492static struct clk_init_data ds3231_clks_init[] = {
1493 [DS3231_CLK_SQW] = {
1494 .name = "ds3231_clk_sqw",
1495 .ops = &ds3231_clk_sqw_ops,
1496 },
1497 [DS3231_CLK_32KHZ] = {
1498 .name = "ds3231_clk_32khz",
1499 .ops = &ds3231_clk_32khz_ops,
1500 },
1501};
1502
1503static int ds3231_clks_register(struct ds1307 *ds1307)
1504{
1505 struct device_node *node = ds1307->dev->of_node;
1506 struct clk_onecell_data *onecell;
1507 int i;
1508
1509 onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL);
1510 if (!onecell)
1511 return -ENOMEM;
1512
1513 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init);
1514 onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num,
1515 sizeof(onecell->clks[0]), GFP_KERNEL);
1516 if (!onecell->clks)
1517 return -ENOMEM;
1518
1519 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) {
1520 struct clk_init_data init = ds3231_clks_init[i];
1521
1522 /*
1523 * Interrupt signal due to alarm conditions and square-wave
1524 * output share same pin, so don't initialize both.
1525 */
1526 if (i == DS3231_CLK_SQW && test_bit(HAS_ALARM, &ds1307->flags))
1527 continue;
1528
1529 /* optional override of the clockname */
1530 of_property_read_string_index(node, "clock-output-names", i,
1531 &init.name);
1532 ds1307->clks[i].init = &init;
1533
1534 onecell->clks[i] = devm_clk_register(ds1307->dev,
1535 &ds1307->clks[i]);
1536 if (IS_ERR(onecell->clks[i]))
1537 return PTR_ERR(onecell->clks[i]);
1538 }
1539
1540 if (!node)
1541 return 0;
1542
1543 of_clk_add_provider(node, of_clk_src_onecell_get, onecell);
1544
1545 return 0;
1546}
1547
1548static void ds1307_clks_register(struct ds1307 *ds1307)
1549{
1550 int ret;
1551
1552 if (ds1307->type != ds_3231)
1553 return;
1554
1555 ret = ds3231_clks_register(ds1307);
1556 if (ret) {
1557 dev_warn(ds1307->dev, "unable to register clock device %d\n",
1558 ret);
1559 }
1560}
1561
1562#else
1563
1564static void ds1307_clks_register(struct ds1307 *ds1307)
1565{
1566}
1567
1568#endif /* CONFIG_COMMON_CLK */
1569
1570static const struct regmap_config regmap_config = {
1571 .reg_bits = 8,
1572 .val_bits = 8,
1573};
1574
1575static int ds1307_probe(struct i2c_client *client,
1576 const struct i2c_device_id *id)
1577{
1578 struct ds1307 *ds1307;
1579 int err = -ENODEV;
1580 int tmp;
1581 const struct chip_desc *chip;
1582 bool want_irq;
1583 bool ds1307_can_wakeup_device = false;
1584 unsigned char regs[8];
1585 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
1586 u8 trickle_charger_setup = 0;
1587
1588 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
1589 if (!ds1307)
1590 return -ENOMEM;
1591
1592 dev_set_drvdata(&client->dev, ds1307);
1593 ds1307->dev = &client->dev;
1594 ds1307->name = client->name;
1595
1596 ds1307->regmap = devm_regmap_init_i2c(client, ®map_config);
1597 if (IS_ERR(ds1307->regmap)) {
1598 dev_err(ds1307->dev, "regmap allocation failed\n");
1599 return PTR_ERR(ds1307->regmap);
1600 }
1601
1602 i2c_set_clientdata(client, ds1307);
1603
1604 if (client->dev.of_node) {
1605 ds1307->type = (enum ds_type)
1606 of_device_get_match_data(&client->dev);
1607 chip = &chips[ds1307->type];
1608 } else if (id) {
1609 chip = &chips[id->driver_data];
1610 ds1307->type = id->driver_data;
1611 } else {
1612 const struct acpi_device_id *acpi_id;
1613
1614 acpi_id = acpi_match_device(ACPI_PTR(ds1307_acpi_ids),
1615 ds1307->dev);
1616 if (!acpi_id)
1617 return -ENODEV;
1618 chip = &chips[acpi_id->driver_data];
1619 ds1307->type = acpi_id->driver_data;
1620 }
1621
1622 want_irq = client->irq > 0 && chip->alarm;
1623
1624 if (!pdata)
1625 trickle_charger_setup = ds1307_trickle_init(ds1307, chip);
1626 else if (pdata->trickle_charger_setup)
1627 trickle_charger_setup = pdata->trickle_charger_setup;
1628
1629 if (trickle_charger_setup && chip->trickle_charger_reg) {
1630 trickle_charger_setup |= DS13XX_TRICKLE_CHARGER_MAGIC;
1631 dev_dbg(ds1307->dev,
1632 "writing trickle charger info 0x%x to 0x%x\n",
1633 trickle_charger_setup, chip->trickle_charger_reg);
1634 regmap_write(ds1307->regmap, chip->trickle_charger_reg,
1635 trickle_charger_setup);
1636 }
1637
1638#ifdef CONFIG_OF
1639/*
1640 * For devices with no IRQ directly connected to the SoC, the RTC chip
1641 * can be forced as a wakeup source by stating that explicitly in
1642 * the device's .dts file using the "wakeup-source" boolean property.
1643 * If the "wakeup-source" property is set, don't request an IRQ.
1644 * This will guarantee the 'wakealarm' sysfs entry is available on the device,
1645 * if supported by the RTC.
1646 */
1647 if (chip->alarm && of_property_read_bool(client->dev.of_node,
1648 "wakeup-source"))
1649 ds1307_can_wakeup_device = true;
1650#endif
1651
1652 switch (ds1307->type) {
1653 case ds_1337:
1654 case ds_1339:
1655 case ds_1341:
1656 case ds_3231:
1657 /* get registers that the "rtc" read below won't read... */
1658 err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL,
1659 regs, 2);
1660 if (err) {
1661 dev_dbg(ds1307->dev, "read error %d\n", err);
1662 goto exit;
1663 }
1664
1665 /* oscillator off? turn it on, so clock can tick. */
1666 if (regs[0] & DS1337_BIT_nEOSC)
1667 regs[0] &= ~DS1337_BIT_nEOSC;
1668
1669 /*
1670 * Using IRQ or defined as wakeup-source?
1671 * Disable the square wave and both alarms.
1672 * For some variants, be sure alarms can trigger when we're
1673 * running on Vbackup (BBSQI/BBSQW)
1674 */
1675 if (want_irq || ds1307_can_wakeup_device) {
1676 regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;
1677 regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
1678 }
1679
1680 regmap_write(ds1307->regmap, DS1337_REG_CONTROL,
1681 regs[0]);
1682
1683 /* oscillator fault? clear flag, and warn */
1684 if (regs[1] & DS1337_BIT_OSF) {
1685 regmap_write(ds1307->regmap, DS1337_REG_STATUS,
1686 regs[1] & ~DS1337_BIT_OSF);
1687 dev_warn(ds1307->dev, "SET TIME!\n");
1688 }
1689 break;
1690
1691 case rx_8025:
1692 err = regmap_bulk_read(ds1307->regmap,
1693 RX8025_REG_CTRL1 << 4 | 0x08, regs, 2);
1694 if (err) {
1695 dev_dbg(ds1307->dev, "read error %d\n", err);
1696 goto exit;
1697 }
1698
1699 /* oscillator off? turn it on, so clock can tick. */
1700 if (!(regs[1] & RX8025_BIT_XST)) {
1701 regs[1] |= RX8025_BIT_XST;
1702 regmap_write(ds1307->regmap,
1703 RX8025_REG_CTRL2 << 4 | 0x08,
1704 regs[1]);
1705 dev_warn(ds1307->dev,
1706 "oscillator stop detected - SET TIME!\n");
1707 }
1708
1709 if (regs[1] & RX8025_BIT_PON) {
1710 regs[1] &= ~RX8025_BIT_PON;
1711 regmap_write(ds1307->regmap,
1712 RX8025_REG_CTRL2 << 4 | 0x08,
1713 regs[1]);
1714 dev_warn(ds1307->dev, "power-on detected\n");
1715 }
1716
1717 if (regs[1] & RX8025_BIT_VDET) {
1718 regs[1] &= ~RX8025_BIT_VDET;
1719 regmap_write(ds1307->regmap,
1720 RX8025_REG_CTRL2 << 4 | 0x08,
1721 regs[1]);
1722 dev_warn(ds1307->dev, "voltage drop detected\n");
1723 }
1724
1725 /* make sure we are running in 24hour mode */
1726 if (!(regs[0] & RX8025_BIT_2412)) {
1727 u8 hour;
1728
1729 /* switch to 24 hour mode */
1730 regmap_write(ds1307->regmap,
1731 RX8025_REG_CTRL1 << 4 | 0x08,
1732 regs[0] | RX8025_BIT_2412);
1733
1734 err = regmap_bulk_read(ds1307->regmap,
1735 RX8025_REG_CTRL1 << 4 | 0x08,
1736 regs, 2);
1737 if (err) {
1738 dev_dbg(ds1307->dev, "read error %d\n", err);
1739 goto exit;
1740 }
1741
1742 /* correct hour */
1743 hour = bcd2bin(regs[DS1307_REG_HOUR]);
1744 if (hour == 12)
1745 hour = 0;
1746 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1747 hour += 12;
1748
1749 regmap_write(ds1307->regmap,
1750 DS1307_REG_HOUR << 4 | 0x08, hour);
1751 }
1752 break;
1753 default:
1754 break;
1755 }
1756
1757 /* read RTC registers */
1758 err = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
1759 sizeof(regs));
1760 if (err) {
1761 dev_dbg(ds1307->dev, "read error %d\n", err);
1762 goto exit;
1763 }
1764
1765 if (ds1307->type == mcp794xx &&
1766 !(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
1767 regmap_write(ds1307->regmap, DS1307_REG_WDAY,
1768 regs[DS1307_REG_WDAY] |
1769 MCP794XX_BIT_VBATEN);
1770 }
1771
1772 tmp = regs[DS1307_REG_HOUR];
1773 switch (ds1307->type) {
1774 case ds_1340:
1775 case m41t0:
1776 case m41t00:
1777 case m41t11:
1778 /*
1779 * NOTE: ignores century bits; fix before deploying
1780 * systems that will run through year 2100.
1781 */
1782 break;
1783 case rx_8025:
1784 break;
1785 default:
1786 if (!(tmp & DS1307_BIT_12HR))
1787 break;
1788
1789 /*
1790 * Be sure we're in 24 hour mode. Multi-master systems
1791 * take note...
1792 */
1793 tmp = bcd2bin(tmp & 0x1f);
1794 if (tmp == 12)
1795 tmp = 0;
1796 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1797 tmp += 12;
1798 regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR,
1799 bin2bcd(tmp));
1800 }
1801
1802 if (want_irq || ds1307_can_wakeup_device) {
1803 device_set_wakeup_capable(ds1307->dev, true);
1804 set_bit(HAS_ALARM, &ds1307->flags);
1805 }
1806
1807 ds1307->rtc = devm_rtc_allocate_device(ds1307->dev);
1808 if (IS_ERR(ds1307->rtc))
1809 return PTR_ERR(ds1307->rtc);
1810
1811 if (ds1307_can_wakeup_device && !want_irq) {
1812 dev_info(ds1307->dev,
1813 "'wakeup-source' is set, request for an IRQ is disabled!\n");
1814 /* We cannot support UIE mode if we do not have an IRQ line */
1815 ds1307->rtc->uie_unsupported = 1;
1816 }
1817
1818 if (want_irq) {
1819 err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL,
1820 chip->irq_handler ?: ds1307_irq,
1821 IRQF_SHARED | IRQF_ONESHOT,
1822 ds1307->name, ds1307);
1823 if (err) {
1824 client->irq = 0;
1825 device_set_wakeup_capable(ds1307->dev, false);
1826 clear_bit(HAS_ALARM, &ds1307->flags);
1827 dev_err(ds1307->dev, "unable to request IRQ!\n");
1828 } else {
1829 dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq);
1830 }
1831 }
1832
1833 ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops;
1834 err = ds1307_add_frequency_test(ds1307);
1835 if (err)
1836 return err;
1837
1838 err = rtc_register_device(ds1307->rtc);
1839 if (err)
1840 return err;
1841
1842 if (chip->nvram_size) {
1843 struct nvmem_config nvmem_cfg = {
1844 .name = "ds1307_nvram",
1845 .word_size = 1,
1846 .stride = 1,
1847 .size = chip->nvram_size,
1848 .reg_read = ds1307_nvram_read,
1849 .reg_write = ds1307_nvram_write,
1850 .priv = ds1307,
1851 };
1852
1853 ds1307->rtc->nvram_old_abi = true;
1854 rtc_nvmem_register(ds1307->rtc, &nvmem_cfg);
1855 }
1856
1857 ds1307_hwmon_register(ds1307);
1858 ds1307_clks_register(ds1307);
1859
1860 return 0;
1861
1862exit:
1863 return err;
1864}
1865
1866static struct i2c_driver ds1307_driver = {
1867 .driver = {
1868 .name = "rtc-ds1307",
1869 .of_match_table = of_match_ptr(ds1307_of_match),
1870 .acpi_match_table = ACPI_PTR(ds1307_acpi_ids),
1871 },
1872 .probe = ds1307_probe,
1873 .id_table = ds1307_id,
1874};
1875
1876module_i2c_driver(ds1307_driver);
1877
1878MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1879MODULE_LICENSE("GPL");