2 * rtc-ds1307.c - RTC driver for some mostly-compatible I2C chips.
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)
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.
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>
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.
51 last_ds_type /* always last */
52 /* rs5c372 too? different address... */
55 /* RTC registers don't differ much, except for the century flag */
56 #define DS1307_REG_SECS 0x00 /* 00-59 */
57 # define DS1307_BIT_CH 0x80
58 # define DS1340_BIT_nEOSC 0x80
59 # define MCP794XX_BIT_ST 0x80
60 #define DS1307_REG_MIN 0x01 /* 00-59 */
61 # define M41T0_BIT_OF 0x80
62 #define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
63 # define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
64 # define DS1307_BIT_PM 0x20 /* in REG_HOUR */
65 # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
66 # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
67 #define DS1307_REG_WDAY 0x03 /* 01-07 */
68 # define MCP794XX_BIT_VBATEN 0x08
69 #define DS1307_REG_MDAY 0x04 /* 01-31 */
70 #define DS1307_REG_MONTH 0x05 /* 01-12 */
71 # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
72 #define DS1307_REG_YEAR 0x06 /* 00-99 */
75 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
76 * start at 7, and they differ a LOT. Only control and status matter for
77 * basic RTC date and time functionality; be careful using them.
79 #define DS1307_REG_CONTROL 0x07 /* or ds1338 */
80 # define DS1307_BIT_OUT 0x80
81 # define DS1338_BIT_OSF 0x20
82 # define DS1307_BIT_SQWE 0x10
83 # define DS1307_BIT_RS1 0x02
84 # define DS1307_BIT_RS0 0x01
85 #define DS1337_REG_CONTROL 0x0e
86 # define DS1337_BIT_nEOSC 0x80
87 # define DS1339_BIT_BBSQI 0x20
88 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
89 # define DS1337_BIT_RS2 0x10
90 # define DS1337_BIT_RS1 0x08
91 # define DS1337_BIT_INTCN 0x04
92 # define DS1337_BIT_A2IE 0x02
93 # define DS1337_BIT_A1IE 0x01
94 #define DS1340_REG_CONTROL 0x07
95 # define DS1340_BIT_OUT 0x80
96 # define DS1340_BIT_FT 0x40
97 # define DS1340_BIT_CALIB_SIGN 0x20
98 # define DS1340_M_CALIBRATION 0x1f
99 #define DS1340_REG_FLAG 0x09
100 # define DS1340_BIT_OSF 0x80
101 #define DS1337_REG_STATUS 0x0f
102 # define DS1337_BIT_OSF 0x80
103 # define DS3231_BIT_EN32KHZ 0x08
104 # define DS1337_BIT_A2I 0x02
105 # define DS1337_BIT_A1I 0x01
106 #define DS1339_REG_ALARM1_SECS 0x07
108 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
110 #define RX8025_REG_CTRL1 0x0e
111 # define RX8025_BIT_2412 0x20
112 #define RX8025_REG_CTRL2 0x0f
113 # define RX8025_BIT_PON 0x10
114 # define RX8025_BIT_VDET 0x40
115 # define RX8025_BIT_XST 0x20
117 #define RX8130_REG_ALARM_MIN 0x17
118 #define RX8130_REG_ALARM_HOUR 0x18
119 #define RX8130_REG_ALARM_WEEK_OR_DAY 0x19
120 #define RX8130_REG_EXTENSION 0x1c
121 #define RX8130_REG_EXTENSION_WADA BIT(3)
122 #define RX8130_REG_FLAG 0x1d
123 #define RX8130_REG_FLAG_VLF BIT(1)
124 #define RX8130_REG_FLAG_AF BIT(3)
125 #define RX8130_REG_CONTROL0 0x1e
126 #define RX8130_REG_CONTROL0_AIE BIT(3)
128 #define MCP794XX_REG_CONTROL 0x07
129 # define MCP794XX_BIT_ALM0_EN 0x10
130 # define MCP794XX_BIT_ALM1_EN 0x20
131 #define MCP794XX_REG_ALARM0_BASE 0x0a
132 #define MCP794XX_REG_ALARM0_CTRL 0x0d
133 #define MCP794XX_REG_ALARM1_BASE 0x11
134 #define MCP794XX_REG_ALARM1_CTRL 0x14
135 # define MCP794XX_BIT_ALMX_IF BIT(3)
136 # define MCP794XX_BIT_ALMX_C0 BIT(4)
137 # define MCP794XX_BIT_ALMX_C1 BIT(5)
138 # define MCP794XX_BIT_ALMX_C2 BIT(6)
139 # define MCP794XX_BIT_ALMX_POL BIT(7)
140 # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
141 MCP794XX_BIT_ALMX_C1 | \
142 MCP794XX_BIT_ALMX_C2)
144 #define M41TXX_REG_CONTROL 0x07
145 # define M41TXX_BIT_OUT BIT(7)
146 # define M41TXX_BIT_FT BIT(6)
147 # define M41TXX_BIT_CALIB_SIGN BIT(5)
148 # define M41TXX_M_CALIBRATION GENMASK(4, 0)
150 /* negative offset step is -2.034ppm */
151 #define M41TXX_NEG_OFFSET_STEP_PPB 2034
152 /* positive offset step is +4.068ppm */
153 #define M41TXX_POS_OFFSET_STEP_PPB 4068
154 /* Min and max values supported with 'offset' interface by M41TXX */
155 #define M41TXX_MIN_OFFSET ((-31) * M41TXX_NEG_OFFSET_STEP_PPB)
156 #define M41TXX_MAX_OFFSET ((31) * M41TXX_POS_OFFSET_STEP_PPB)
161 #define HAS_NVRAM 0 /* bit 0 == sysfs file active */
162 #define HAS_ALARM 1 /* bit 1 == irq claimed */
164 struct regmap *regmap;
166 struct rtc_device *rtc;
167 #ifdef CONFIG_COMMON_CLK
168 struct clk_hw clks[2];
176 u8 offset; /* register's offset */
178 u8 century_enable_bit;
181 irq_handler_t irq_handler;
182 const struct rtc_class_ops *rtc_ops;
183 u16 trickle_charger_reg;
184 u8 (*do_trickle_setup)(struct ds1307 *, u32,
188 static const struct chip_desc chips[last_ds_type];
190 static int ds1307_get_time(struct device *dev, struct rtc_time *t)
192 struct ds1307 *ds1307 = dev_get_drvdata(dev);
194 const struct chip_desc *chip = &chips[ds1307->type];
197 if (ds1307->type == rx_8130) {
198 unsigned int regflag;
199 ret = regmap_read(ds1307->regmap, RX8130_REG_FLAG, ®flag);
201 dev_err(dev, "%s error %d\n", "read", ret);
205 if (regflag & RX8130_REG_FLAG_VLF) {
206 dev_warn_once(dev, "oscillator failed, set time!\n");
211 /* read the RTC date and time registers all at once */
212 ret = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
215 dev_err(dev, "%s error %d\n", "read", ret);
219 dev_dbg(dev, "%s: %7ph\n", "read", regs);
221 /* if oscillator fail bit is set, no data can be trusted */
222 if (ds1307->type == m41t0 &&
223 regs[DS1307_REG_MIN] & M41T0_BIT_OF) {
224 dev_warn_once(dev, "oscillator failed, set time!\n");
228 t->tm_sec = bcd2bin(regs[DS1307_REG_SECS] & 0x7f);
229 t->tm_min = bcd2bin(regs[DS1307_REG_MIN] & 0x7f);
230 tmp = regs[DS1307_REG_HOUR] & 0x3f;
231 t->tm_hour = bcd2bin(tmp);
232 t->tm_wday = bcd2bin(regs[DS1307_REG_WDAY] & 0x07) - 1;
233 t->tm_mday = bcd2bin(regs[DS1307_REG_MDAY] & 0x3f);
234 tmp = regs[DS1307_REG_MONTH] & 0x1f;
235 t->tm_mon = bcd2bin(tmp) - 1;
236 t->tm_year = bcd2bin(regs[DS1307_REG_YEAR]) + 100;
238 if (regs[chip->century_reg] & chip->century_bit &&
239 IS_ENABLED(CONFIG_RTC_DRV_DS1307_CENTURY))
242 dev_dbg(dev, "%s secs=%d, mins=%d, "
243 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
244 "read", t->tm_sec, t->tm_min,
245 t->tm_hour, t->tm_mday,
246 t->tm_mon, t->tm_year, t->tm_wday);
251 static int ds1307_set_time(struct device *dev, struct rtc_time *t)
253 struct ds1307 *ds1307 = dev_get_drvdata(dev);
254 const struct chip_desc *chip = &chips[ds1307->type];
259 dev_dbg(dev, "%s secs=%d, mins=%d, "
260 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
261 "write", t->tm_sec, t->tm_min,
262 t->tm_hour, t->tm_mday,
263 t->tm_mon, t->tm_year, t->tm_wday);
265 if (t->tm_year < 100)
268 #ifdef CONFIG_RTC_DRV_DS1307_CENTURY
269 if (t->tm_year > (chip->century_bit ? 299 : 199))
272 if (t->tm_year > 199)
276 regs[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
277 regs[DS1307_REG_MIN] = bin2bcd(t->tm_min);
278 regs[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
279 regs[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
280 regs[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
281 regs[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
283 /* assume 20YY not 19YY */
284 tmp = t->tm_year - 100;
285 regs[DS1307_REG_YEAR] = bin2bcd(tmp);
287 if (chip->century_enable_bit)
288 regs[chip->century_reg] |= chip->century_enable_bit;
289 if (t->tm_year > 199 && chip->century_bit)
290 regs[chip->century_reg] |= chip->century_bit;
292 if (ds1307->type == mcp794xx) {
294 * these bits were cleared when preparing the date/time
295 * values and need to be set again before writing the
296 * regsfer out to the device.
298 regs[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
299 regs[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
302 dev_dbg(dev, "%s: %7ph\n", "write", regs);
304 result = regmap_bulk_write(ds1307->regmap, chip->offset, regs,
307 dev_err(dev, "%s error %d\n", "write", result);
311 if (ds1307->type == rx_8130) {
312 /* clear Voltage Loss Flag as data is available now */
313 result = regmap_write(ds1307->regmap, RX8130_REG_FLAG,
314 ~(u8)RX8130_REG_FLAG_VLF);
316 dev_err(dev, "%s error %d\n", "write", result);
324 static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
326 struct ds1307 *ds1307 = dev_get_drvdata(dev);
330 if (!test_bit(HAS_ALARM, &ds1307->flags))
333 /* read all ALARM1, ALARM2, and status registers at once */
334 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS,
337 dev_err(dev, "%s error %d\n", "alarm read", ret);
341 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
342 ®s[0], ®s[4], ®s[7]);
345 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
346 * and that all four fields are checked matches
348 t->time.tm_sec = bcd2bin(regs[0] & 0x7f);
349 t->time.tm_min = bcd2bin(regs[1] & 0x7f);
350 t->time.tm_hour = bcd2bin(regs[2] & 0x3f);
351 t->time.tm_mday = bcd2bin(regs[3] & 0x3f);
354 t->enabled = !!(regs[7] & DS1337_BIT_A1IE);
355 t->pending = !!(regs[8] & DS1337_BIT_A1I);
357 dev_dbg(dev, "%s secs=%d, mins=%d, "
358 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
359 "alarm read", t->time.tm_sec, t->time.tm_min,
360 t->time.tm_hour, t->time.tm_mday,
361 t->enabled, t->pending);
366 static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
368 struct ds1307 *ds1307 = dev_get_drvdata(dev);
369 unsigned char regs[9];
373 if (!test_bit(HAS_ALARM, &ds1307->flags))
376 dev_dbg(dev, "%s secs=%d, mins=%d, "
377 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
378 "alarm set", t->time.tm_sec, t->time.tm_min,
379 t->time.tm_hour, t->time.tm_mday,
380 t->enabled, t->pending);
382 /* read current status of both alarms and the chip */
383 ret = regmap_bulk_read(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
386 dev_err(dev, "%s error %d\n", "alarm write", ret);
392 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
393 ®s[0], ®s[4], control, status);
395 /* set ALARM1, using 24 hour and day-of-month modes */
396 regs[0] = bin2bcd(t->time.tm_sec);
397 regs[1] = bin2bcd(t->time.tm_min);
398 regs[2] = bin2bcd(t->time.tm_hour);
399 regs[3] = bin2bcd(t->time.tm_mday);
401 /* set ALARM2 to non-garbage */
407 regs[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
408 regs[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
410 ret = regmap_bulk_write(ds1307->regmap, DS1339_REG_ALARM1_SECS, regs,
413 dev_err(dev, "can't set alarm time\n");
417 /* optionally enable ALARM1 */
419 dev_dbg(dev, "alarm IRQ armed\n");
420 regs[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
421 regmap_write(ds1307->regmap, DS1337_REG_CONTROL, regs[7]);
427 static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
429 struct ds1307 *ds1307 = dev_get_drvdata(dev);
431 if (!test_bit(HAS_ALARM, &ds1307->flags))
434 return regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
436 enabled ? DS1337_BIT_A1IE : 0);
439 static u8 do_trickle_setup_ds1339(struct ds1307 *ds1307, u32 ohms, bool diode)
441 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
442 DS1307_TRICKLE_CHARGER_NO_DIODE;
446 setup |= DS1307_TRICKLE_CHARGER_250_OHM;
449 setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
452 setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
455 dev_warn(ds1307->dev,
456 "Unsupported ohm value %u in dt\n", ohms);
462 static irqreturn_t rx8130_irq(int irq, void *dev_id)
464 struct ds1307 *ds1307 = dev_id;
465 struct mutex *lock = &ds1307->rtc->ops_lock;
471 /* Read control registers. */
472 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
476 if (!(ctl[1] & RX8130_REG_FLAG_AF))
478 ctl[1] &= ~RX8130_REG_FLAG_AF;
479 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
481 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
486 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
494 static int rx8130_read_alarm(struct device *dev, struct rtc_wkalrm *t)
496 struct ds1307 *ds1307 = dev_get_drvdata(dev);
500 if (!test_bit(HAS_ALARM, &ds1307->flags))
503 /* Read alarm registers. */
504 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
509 /* Read control registers. */
510 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
515 t->enabled = !!(ctl[2] & RX8130_REG_CONTROL0_AIE);
516 t->pending = !!(ctl[1] & RX8130_REG_FLAG_AF);
518 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
520 t->time.tm_min = bcd2bin(ald[0] & 0x7f);
521 t->time.tm_hour = bcd2bin(ald[1] & 0x7f);
522 t->time.tm_wday = -1;
523 t->time.tm_mday = bcd2bin(ald[2] & 0x7f);
525 t->time.tm_year = -1;
526 t->time.tm_yday = -1;
527 t->time.tm_isdst = -1;
529 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d enabled=%d\n",
530 __func__, t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
531 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled);
536 static int rx8130_set_alarm(struct device *dev, struct rtc_wkalrm *t)
538 struct ds1307 *ds1307 = dev_get_drvdata(dev);
542 if (!test_bit(HAS_ALARM, &ds1307->flags))
545 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
546 "enabled=%d pending=%d\n", __func__,
547 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
548 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
549 t->enabled, t->pending);
551 /* Read control registers. */
552 ret = regmap_bulk_read(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
557 ctl[0] &= RX8130_REG_EXTENSION_WADA;
558 ctl[1] &= ~RX8130_REG_FLAG_AF;
559 ctl[2] &= ~RX8130_REG_CONTROL0_AIE;
561 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_EXTENSION, ctl,
566 /* Hardware alarm precision is 1 minute! */
567 ald[0] = bin2bcd(t->time.tm_min);
568 ald[1] = bin2bcd(t->time.tm_hour);
569 ald[2] = bin2bcd(t->time.tm_mday);
571 ret = regmap_bulk_write(ds1307->regmap, RX8130_REG_ALARM_MIN, ald,
579 ctl[2] |= RX8130_REG_CONTROL0_AIE;
581 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, ctl[2]);
584 static int rx8130_alarm_irq_enable(struct device *dev, unsigned int enabled)
586 struct ds1307 *ds1307 = dev_get_drvdata(dev);
589 if (!test_bit(HAS_ALARM, &ds1307->flags))
592 ret = regmap_read(ds1307->regmap, RX8130_REG_CONTROL0, ®);
597 reg |= RX8130_REG_CONTROL0_AIE;
599 reg &= ~RX8130_REG_CONTROL0_AIE;
601 return regmap_write(ds1307->regmap, RX8130_REG_CONTROL0, reg);
604 static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
606 struct ds1307 *ds1307 = dev_id;
607 struct mutex *lock = &ds1307->rtc->ops_lock;
612 /* Check and clear alarm 0 interrupt flag. */
613 ret = regmap_read(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, ®);
616 if (!(reg & MCP794XX_BIT_ALMX_IF))
618 reg &= ~MCP794XX_BIT_ALMX_IF;
619 ret = regmap_write(ds1307->regmap, MCP794XX_REG_ALARM0_CTRL, reg);
623 /* Disable alarm 0. */
624 ret = regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
625 MCP794XX_BIT_ALM0_EN, 0);
629 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
637 static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)
639 struct ds1307 *ds1307 = dev_get_drvdata(dev);
643 if (!test_bit(HAS_ALARM, &ds1307->flags))
646 /* Read control and alarm 0 registers. */
647 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
652 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);
654 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
655 t->time.tm_sec = bcd2bin(regs[3] & 0x7f);
656 t->time.tm_min = bcd2bin(regs[4] & 0x7f);
657 t->time.tm_hour = bcd2bin(regs[5] & 0x3f);
658 t->time.tm_wday = bcd2bin(regs[6] & 0x7) - 1;
659 t->time.tm_mday = bcd2bin(regs[7] & 0x3f);
660 t->time.tm_mon = bcd2bin(regs[8] & 0x1f) - 1;
661 t->time.tm_year = -1;
662 t->time.tm_yday = -1;
663 t->time.tm_isdst = -1;
665 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
666 "enabled=%d polarity=%d irq=%d match=%lu\n", __func__,
667 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
668 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
669 !!(regs[6] & MCP794XX_BIT_ALMX_POL),
670 !!(regs[6] & MCP794XX_BIT_ALMX_IF),
671 (regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
677 * We may have a random RTC weekday, therefore calculate alarm weekday based
678 * on current weekday we read from the RTC timekeeping regs
680 static int mcp794xx_alm_weekday(struct device *dev, struct rtc_time *tm_alarm)
682 struct rtc_time tm_now;
683 int days_now, days_alarm, ret;
685 ret = ds1307_get_time(dev, &tm_now);
689 days_now = div_s64(rtc_tm_to_time64(&tm_now), 24 * 60 * 60);
690 days_alarm = div_s64(rtc_tm_to_time64(tm_alarm), 24 * 60 * 60);
692 return (tm_now.tm_wday + days_alarm - days_now) % 7 + 1;
695 static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
697 struct ds1307 *ds1307 = dev_get_drvdata(dev);
698 unsigned char regs[10];
701 if (!test_bit(HAS_ALARM, &ds1307->flags))
704 wday = mcp794xx_alm_weekday(dev, &t->time);
708 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
709 "enabled=%d pending=%d\n", __func__,
710 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
711 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
712 t->enabled, t->pending);
714 /* Read control and alarm 0 registers. */
715 ret = regmap_bulk_read(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
720 /* Set alarm 0, using 24-hour and day-of-month modes. */
721 regs[3] = bin2bcd(t->time.tm_sec);
722 regs[4] = bin2bcd(t->time.tm_min);
723 regs[5] = bin2bcd(t->time.tm_hour);
725 regs[7] = bin2bcd(t->time.tm_mday);
726 regs[8] = bin2bcd(t->time.tm_mon + 1);
728 /* Clear the alarm 0 interrupt flag. */
729 regs[6] &= ~MCP794XX_BIT_ALMX_IF;
730 /* Set alarm match: second, minute, hour, day, date, month. */
731 regs[6] |= MCP794XX_MSK_ALMX_MATCH;
732 /* Disable interrupt. We will not enable until completely programmed */
733 regs[0] &= ~MCP794XX_BIT_ALM0_EN;
735 ret = regmap_bulk_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs,
742 regs[0] |= MCP794XX_BIT_ALM0_EN;
743 return regmap_write(ds1307->regmap, MCP794XX_REG_CONTROL, regs[0]);
746 static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
748 struct ds1307 *ds1307 = dev_get_drvdata(dev);
750 if (!test_bit(HAS_ALARM, &ds1307->flags))
753 return regmap_update_bits(ds1307->regmap, MCP794XX_REG_CONTROL,
754 MCP794XX_BIT_ALM0_EN,
755 enabled ? MCP794XX_BIT_ALM0_EN : 0);
758 static int m41txx_rtc_read_offset(struct device *dev, long *offset)
760 struct ds1307 *ds1307 = dev_get_drvdata(dev);
761 unsigned int ctrl_reg;
764 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
766 val = ctrl_reg & M41TXX_M_CALIBRATION;
768 /* check if positive */
769 if (ctrl_reg & M41TXX_BIT_CALIB_SIGN)
770 *offset = (val * M41TXX_POS_OFFSET_STEP_PPB);
772 *offset = -(val * M41TXX_NEG_OFFSET_STEP_PPB);
777 static int m41txx_rtc_set_offset(struct device *dev, long offset)
779 struct ds1307 *ds1307 = dev_get_drvdata(dev);
780 unsigned int ctrl_reg;
782 if ((offset < M41TXX_MIN_OFFSET) || (offset > M41TXX_MAX_OFFSET))
786 ctrl_reg = DIV_ROUND_CLOSEST(offset,
787 M41TXX_POS_OFFSET_STEP_PPB);
788 ctrl_reg |= M41TXX_BIT_CALIB_SIGN;
790 ctrl_reg = DIV_ROUND_CLOSEST(abs(offset),
791 M41TXX_NEG_OFFSET_STEP_PPB);
794 return regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL,
795 M41TXX_M_CALIBRATION | M41TXX_BIT_CALIB_SIGN,
799 static const struct rtc_class_ops rx8130_rtc_ops = {
800 .read_time = ds1307_get_time,
801 .set_time = ds1307_set_time,
802 .read_alarm = rx8130_read_alarm,
803 .set_alarm = rx8130_set_alarm,
804 .alarm_irq_enable = rx8130_alarm_irq_enable,
807 static const struct rtc_class_ops mcp794xx_rtc_ops = {
808 .read_time = ds1307_get_time,
809 .set_time = ds1307_set_time,
810 .read_alarm = mcp794xx_read_alarm,
811 .set_alarm = mcp794xx_set_alarm,
812 .alarm_irq_enable = mcp794xx_alarm_irq_enable,
815 static const struct rtc_class_ops m41txx_rtc_ops = {
816 .read_time = ds1307_get_time,
817 .set_time = ds1307_set_time,
818 .read_alarm = ds1337_read_alarm,
819 .set_alarm = ds1337_set_alarm,
820 .alarm_irq_enable = ds1307_alarm_irq_enable,
821 .read_offset = m41txx_rtc_read_offset,
822 .set_offset = m41txx_rtc_set_offset,
825 static const struct chip_desc chips[last_ds_type] = {
836 .century_reg = DS1307_REG_MONTH,
837 .century_bit = DS1337_BIT_CENTURY,
845 .century_reg = DS1307_REG_MONTH,
846 .century_bit = DS1337_BIT_CENTURY,
847 .bbsqi_bit = DS1339_BIT_BBSQI,
848 .trickle_charger_reg = 0x10,
849 .do_trickle_setup = &do_trickle_setup_ds1339,
852 .century_reg = DS1307_REG_HOUR,
853 .century_enable_bit = DS1340_BIT_CENTURY_EN,
854 .century_bit = DS1340_BIT_CENTURY,
855 .do_trickle_setup = &do_trickle_setup_ds1339,
856 .trickle_charger_reg = 0x08,
859 .century_reg = DS1307_REG_MONTH,
860 .century_bit = DS1337_BIT_CENTURY,
864 .trickle_charger_reg = 0x0a,
868 .century_reg = DS1307_REG_MONTH,
869 .century_bit = DS1337_BIT_CENTURY,
870 .bbsqi_bit = DS3231_BIT_BBSQW,
874 /* this is battery backed SRAM */
875 .nvram_offset = 0x20,
876 .nvram_size = 4, /* 32bit (4 word x 8 bit) */
878 .irq_handler = rx8130_irq,
879 .rtc_ops = &rx8130_rtc_ops,
882 .rtc_ops = &m41txx_rtc_ops,
885 .rtc_ops = &m41txx_rtc_ops,
888 /* this is battery backed SRAM */
891 .rtc_ops = &m41txx_rtc_ops,
895 /* this is battery backed SRAM */
896 .nvram_offset = 0x20,
898 .irq_handler = mcp794xx_irq,
899 .rtc_ops = &mcp794xx_rtc_ops,
903 static const struct i2c_device_id ds1307_id[] = {
904 { "ds1307", ds_1307 },
905 { "ds1308", ds_1308 },
906 { "ds1337", ds_1337 },
907 { "ds1338", ds_1338 },
908 { "ds1339", ds_1339 },
909 { "ds1388", ds_1388 },
910 { "ds1340", ds_1340 },
911 { "ds1341", ds_1341 },
912 { "ds3231", ds_3231 },
914 { "m41t00", m41t00 },
915 { "m41t11", m41t11 },
916 { "mcp7940x", mcp794xx },
917 { "mcp7941x", mcp794xx },
918 { "pt7c4338", ds_1307 },
919 { "rx8025", rx_8025 },
920 { "isl12057", ds_1337 },
921 { "rx8130", rx_8130 },
924 MODULE_DEVICE_TABLE(i2c, ds1307_id);
927 static const struct of_device_id ds1307_of_match[] = {
929 .compatible = "dallas,ds1307",
930 .data = (void *)ds_1307
933 .compatible = "dallas,ds1308",
934 .data = (void *)ds_1308
937 .compatible = "dallas,ds1337",
938 .data = (void *)ds_1337
941 .compatible = "dallas,ds1338",
942 .data = (void *)ds_1338
945 .compatible = "dallas,ds1339",
946 .data = (void *)ds_1339
949 .compatible = "dallas,ds1388",
950 .data = (void *)ds_1388
953 .compatible = "dallas,ds1340",
954 .data = (void *)ds_1340
957 .compatible = "dallas,ds1341",
958 .data = (void *)ds_1341
961 .compatible = "maxim,ds3231",
962 .data = (void *)ds_3231
965 .compatible = "st,m41t0",
966 .data = (void *)m41t0
969 .compatible = "st,m41t00",
970 .data = (void *)m41t00
973 .compatible = "st,m41t11",
974 .data = (void *)m41t11
977 .compatible = "microchip,mcp7940x",
978 .data = (void *)mcp794xx
981 .compatible = "microchip,mcp7941x",
982 .data = (void *)mcp794xx
985 .compatible = "pericom,pt7c4338",
986 .data = (void *)ds_1307
989 .compatible = "epson,rx8025",
990 .data = (void *)rx_8025
993 .compatible = "isil,isl12057",
994 .data = (void *)ds_1337
997 .compatible = "epson,rx8130",
998 .data = (void *)rx_8130
1002 MODULE_DEVICE_TABLE(of, ds1307_of_match);
1006 static const struct acpi_device_id ds1307_acpi_ids[] = {
1007 { .id = "DS1307", .driver_data = ds_1307 },
1008 { .id = "DS1308", .driver_data = ds_1308 },
1009 { .id = "DS1337", .driver_data = ds_1337 },
1010 { .id = "DS1338", .driver_data = ds_1338 },
1011 { .id = "DS1339", .driver_data = ds_1339 },
1012 { .id = "DS1388", .driver_data = ds_1388 },
1013 { .id = "DS1340", .driver_data = ds_1340 },
1014 { .id = "DS1341", .driver_data = ds_1341 },
1015 { .id = "DS3231", .driver_data = ds_3231 },
1016 { .id = "M41T0", .driver_data = m41t0 },
1017 { .id = "M41T00", .driver_data = m41t00 },
1018 { .id = "M41T11", .driver_data = m41t11 },
1019 { .id = "MCP7940X", .driver_data = mcp794xx },
1020 { .id = "MCP7941X", .driver_data = mcp794xx },
1021 { .id = "PT7C4338", .driver_data = ds_1307 },
1022 { .id = "RX8025", .driver_data = rx_8025 },
1023 { .id = "ISL12057", .driver_data = ds_1337 },
1024 { .id = "RX8130", .driver_data = rx_8130 },
1027 MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
1031 * The ds1337 and ds1339 both have two alarms, but we only use the first
1032 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
1033 * signal; ds1339 chips have only one alarm signal.
1035 static irqreturn_t ds1307_irq(int irq, void *dev_id)
1037 struct ds1307 *ds1307 = dev_id;
1038 struct mutex *lock = &ds1307->rtc->ops_lock;
1042 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &stat);
1046 if (stat & DS1337_BIT_A1I) {
1047 stat &= ~DS1337_BIT_A1I;
1048 regmap_write(ds1307->regmap, DS1337_REG_STATUS, stat);
1050 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1051 DS1337_BIT_A1IE, 0);
1055 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
1064 /*----------------------------------------------------------------------*/
1066 static const struct rtc_class_ops ds13xx_rtc_ops = {
1067 .read_time = ds1307_get_time,
1068 .set_time = ds1307_set_time,
1069 .read_alarm = ds1337_read_alarm,
1070 .set_alarm = ds1337_set_alarm,
1071 .alarm_irq_enable = ds1307_alarm_irq_enable,
1074 static ssize_t frequency_test_store(struct device *dev,
1075 struct device_attribute *attr,
1076 const char *buf, size_t count)
1078 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1082 ret = kstrtobool(buf, &freq_test_en);
1084 dev_err(dev, "Failed to store RTC Frequency Test attribute\n");
1088 regmap_update_bits(ds1307->regmap, M41TXX_REG_CONTROL, M41TXX_BIT_FT,
1089 freq_test_en ? M41TXX_BIT_FT : 0);
1094 static ssize_t frequency_test_show(struct device *dev,
1095 struct device_attribute *attr,
1098 struct ds1307 *ds1307 = dev_get_drvdata(dev->parent);
1099 unsigned int ctrl_reg;
1101 regmap_read(ds1307->regmap, M41TXX_REG_CONTROL, &ctrl_reg);
1103 return scnprintf(buf, PAGE_SIZE, (ctrl_reg & M41TXX_BIT_FT) ? "on\n" :
1107 static DEVICE_ATTR_RW(frequency_test);
1109 static struct attribute *rtc_freq_test_attrs[] = {
1110 &dev_attr_frequency_test.attr,
1114 static const struct attribute_group rtc_freq_test_attr_group = {
1115 .attrs = rtc_freq_test_attrs,
1118 static int ds1307_add_frequency_test(struct ds1307 *ds1307)
1122 switch (ds1307->type) {
1126 err = rtc_add_group(ds1307->rtc, &rtc_freq_test_attr_group);
1137 /*----------------------------------------------------------------------*/
1139 static int ds1307_nvram_read(void *priv, unsigned int offset, void *val,
1142 struct ds1307 *ds1307 = priv;
1143 const struct chip_desc *chip = &chips[ds1307->type];
1145 return regmap_bulk_read(ds1307->regmap, chip->nvram_offset + offset,
1149 static int ds1307_nvram_write(void *priv, unsigned int offset, void *val,
1152 struct ds1307 *ds1307 = priv;
1153 const struct chip_desc *chip = &chips[ds1307->type];
1155 return regmap_bulk_write(ds1307->regmap, chip->nvram_offset + offset,
1159 /*----------------------------------------------------------------------*/
1161 static u8 ds1307_trickle_init(struct ds1307 *ds1307,
1162 const struct chip_desc *chip)
1167 if (!chip->do_trickle_setup)
1170 if (device_property_read_u32(ds1307->dev, "trickle-resistor-ohms",
1174 if (device_property_read_bool(ds1307->dev, "trickle-diode-disable"))
1177 return chip->do_trickle_setup(ds1307, ohms, diode);
1180 /*----------------------------------------------------------------------*/
1182 #if IS_REACHABLE(CONFIG_HWMON)
1185 * Temperature sensor support for ds3231 devices.
1188 #define DS3231_REG_TEMPERATURE 0x11
1191 * A user-initiated temperature conversion is not started by this function,
1192 * so the temperature is updated once every 64 seconds.
1194 static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)
1196 struct ds1307 *ds1307 = dev_get_drvdata(dev);
1201 ret = regmap_bulk_read(ds1307->regmap, DS3231_REG_TEMPERATURE,
1202 temp_buf, sizeof(temp_buf));
1206 * Temperature is represented as a 10-bit code with a resolution of
1207 * 0.25 degree celsius and encoded in two's complement format.
1209 temp = (temp_buf[0] << 8) | temp_buf[1];
1216 static ssize_t ds3231_hwmon_show_temp(struct device *dev,
1217 struct device_attribute *attr, char *buf)
1222 ret = ds3231_hwmon_read_temp(dev, &temp);
1226 return sprintf(buf, "%d\n", temp);
1228 static SENSOR_DEVICE_ATTR(temp1_input, 0444, ds3231_hwmon_show_temp,
1231 static struct attribute *ds3231_hwmon_attrs[] = {
1232 &sensor_dev_attr_temp1_input.dev_attr.attr,
1235 ATTRIBUTE_GROUPS(ds3231_hwmon);
1237 static void ds1307_hwmon_register(struct ds1307 *ds1307)
1241 if (ds1307->type != ds_3231)
1244 dev = devm_hwmon_device_register_with_groups(ds1307->dev, ds1307->name,
1246 ds3231_hwmon_groups);
1248 dev_warn(ds1307->dev, "unable to register hwmon device %ld\n",
1255 static void ds1307_hwmon_register(struct ds1307 *ds1307)
1259 #endif /* CONFIG_RTC_DRV_DS1307_HWMON */
1261 /*----------------------------------------------------------------------*/
1264 * Square-wave output support for DS3231
1265 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf
1267 #ifdef CONFIG_COMMON_CLK
1274 #define clk_sqw_to_ds1307(clk) \
1275 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW])
1276 #define clk_32khz_to_ds1307(clk) \
1277 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ])
1279 static int ds3231_clk_sqw_rates[] = {
1286 static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value)
1288 struct mutex *lock = &ds1307->rtc->ops_lock;
1292 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_CONTROL,
1299 static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw,
1300 unsigned long parent_rate)
1302 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1306 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1309 if (control & DS1337_BIT_RS1)
1311 if (control & DS1337_BIT_RS2)
1314 return ds3231_clk_sqw_rates[rate_sel];
1317 static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
1318 unsigned long *prate)
1322 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) {
1323 if (ds3231_clk_sqw_rates[i] <= rate)
1324 return ds3231_clk_sqw_rates[i];
1330 static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
1331 unsigned long parent_rate)
1333 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1337 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates);
1339 if (ds3231_clk_sqw_rates[rate_sel] == rate)
1343 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates))
1347 control |= DS1337_BIT_RS1;
1349 control |= DS1337_BIT_RS2;
1351 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2,
1355 static int ds3231_clk_sqw_prepare(struct clk_hw *hw)
1357 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1359 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0);
1362 static void ds3231_clk_sqw_unprepare(struct clk_hw *hw)
1364 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1366 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN);
1369 static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw)
1371 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1374 ret = regmap_read(ds1307->regmap, DS1337_REG_CONTROL, &control);
1378 return !(control & DS1337_BIT_INTCN);
1381 static const struct clk_ops ds3231_clk_sqw_ops = {
1382 .prepare = ds3231_clk_sqw_prepare,
1383 .unprepare = ds3231_clk_sqw_unprepare,
1384 .is_prepared = ds3231_clk_sqw_is_prepared,
1385 .recalc_rate = ds3231_clk_sqw_recalc_rate,
1386 .round_rate = ds3231_clk_sqw_round_rate,
1387 .set_rate = ds3231_clk_sqw_set_rate,
1390 static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw,
1391 unsigned long parent_rate)
1396 static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable)
1398 struct mutex *lock = &ds1307->rtc->ops_lock;
1402 ret = regmap_update_bits(ds1307->regmap, DS1337_REG_STATUS,
1404 enable ? DS3231_BIT_EN32KHZ : 0);
1410 static int ds3231_clk_32khz_prepare(struct clk_hw *hw)
1412 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1414 return ds3231_clk_32khz_control(ds1307, true);
1417 static void ds3231_clk_32khz_unprepare(struct clk_hw *hw)
1419 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1421 ds3231_clk_32khz_control(ds1307, false);
1424 static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw)
1426 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1429 ret = regmap_read(ds1307->regmap, DS1337_REG_STATUS, &status);
1433 return !!(status & DS3231_BIT_EN32KHZ);
1436 static const struct clk_ops ds3231_clk_32khz_ops = {
1437 .prepare = ds3231_clk_32khz_prepare,
1438 .unprepare = ds3231_clk_32khz_unprepare,
1439 .is_prepared = ds3231_clk_32khz_is_prepared,
1440 .recalc_rate = ds3231_clk_32khz_recalc_rate,
1443 static struct clk_init_data ds3231_clks_init[] = {
1444 [DS3231_CLK_SQW] = {
1445 .name = "ds3231_clk_sqw",
1446 .ops = &ds3231_clk_sqw_ops,
1448 [DS3231_CLK_32KHZ] = {
1449 .name = "ds3231_clk_32khz",
1450 .ops = &ds3231_clk_32khz_ops,
1454 static int ds3231_clks_register(struct ds1307 *ds1307)
1456 struct device_node *node = ds1307->dev->of_node;
1457 struct clk_onecell_data *onecell;
1460 onecell = devm_kzalloc(ds1307->dev, sizeof(*onecell), GFP_KERNEL);
1464 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init);
1465 onecell->clks = devm_kcalloc(ds1307->dev, onecell->clk_num,
1466 sizeof(onecell->clks[0]), GFP_KERNEL);
1470 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) {
1471 struct clk_init_data init = ds3231_clks_init[i];
1474 * Interrupt signal due to alarm conditions and square-wave
1475 * output share same pin, so don't initialize both.
1477 if (i == DS3231_CLK_SQW && test_bit(HAS_ALARM, &ds1307->flags))
1480 /* optional override of the clockname */
1481 of_property_read_string_index(node, "clock-output-names", i,
1483 ds1307->clks[i].init = &init;
1485 onecell->clks[i] = devm_clk_register(ds1307->dev,
1487 if (IS_ERR(onecell->clks[i]))
1488 return PTR_ERR(onecell->clks[i]);
1494 of_clk_add_provider(node, of_clk_src_onecell_get, onecell);
1499 static void ds1307_clks_register(struct ds1307 *ds1307)
1503 if (ds1307->type != ds_3231)
1506 ret = ds3231_clks_register(ds1307);
1508 dev_warn(ds1307->dev, "unable to register clock device %d\n",
1515 static void ds1307_clks_register(struct ds1307 *ds1307)
1519 #endif /* CONFIG_COMMON_CLK */
1521 static const struct regmap_config regmap_config = {
1526 static int ds1307_probe(struct i2c_client *client,
1527 const struct i2c_device_id *id)
1529 struct ds1307 *ds1307;
1532 const struct chip_desc *chip;
1534 bool ds1307_can_wakeup_device = false;
1535 unsigned char regs[8];
1536 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
1537 u8 trickle_charger_setup = 0;
1539 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
1543 dev_set_drvdata(&client->dev, ds1307);
1544 ds1307->dev = &client->dev;
1545 ds1307->name = client->name;
1547 ds1307->regmap = devm_regmap_init_i2c(client, ®map_config);
1548 if (IS_ERR(ds1307->regmap)) {
1549 dev_err(ds1307->dev, "regmap allocation failed\n");
1550 return PTR_ERR(ds1307->regmap);
1553 i2c_set_clientdata(client, ds1307);
1555 if (client->dev.of_node) {
1556 ds1307->type = (enum ds_type)
1557 of_device_get_match_data(&client->dev);
1558 chip = &chips[ds1307->type];
1560 chip = &chips[id->driver_data];
1561 ds1307->type = id->driver_data;
1563 const struct acpi_device_id *acpi_id;
1565 acpi_id = acpi_match_device(ACPI_PTR(ds1307_acpi_ids),
1569 chip = &chips[acpi_id->driver_data];
1570 ds1307->type = acpi_id->driver_data;
1573 want_irq = client->irq > 0 && chip->alarm;
1576 trickle_charger_setup = ds1307_trickle_init(ds1307, chip);
1577 else if (pdata->trickle_charger_setup)
1578 trickle_charger_setup = pdata->trickle_charger_setup;
1580 if (trickle_charger_setup && chip->trickle_charger_reg) {
1581 trickle_charger_setup |= DS13XX_TRICKLE_CHARGER_MAGIC;
1582 dev_dbg(ds1307->dev,
1583 "writing trickle charger info 0x%x to 0x%x\n",
1584 trickle_charger_setup, chip->trickle_charger_reg);
1585 regmap_write(ds1307->regmap, chip->trickle_charger_reg,
1586 trickle_charger_setup);
1591 * For devices with no IRQ directly connected to the SoC, the RTC chip
1592 * can be forced as a wakeup source by stating that explicitly in
1593 * the device's .dts file using the "wakeup-source" boolean property.
1594 * If the "wakeup-source" property is set, don't request an IRQ.
1595 * This will guarantee the 'wakealarm' sysfs entry is available on the device,
1596 * if supported by the RTC.
1598 if (chip->alarm && of_property_read_bool(client->dev.of_node,
1600 ds1307_can_wakeup_device = true;
1603 switch (ds1307->type) {
1608 /* get registers that the "rtc" read below won't read... */
1609 err = regmap_bulk_read(ds1307->regmap, DS1337_REG_CONTROL,
1612 dev_dbg(ds1307->dev, "read error %d\n", err);
1616 /* oscillator off? turn it on, so clock can tick. */
1617 if (regs[0] & DS1337_BIT_nEOSC)
1618 regs[0] &= ~DS1337_BIT_nEOSC;
1621 * Using IRQ or defined as wakeup-source?
1622 * Disable the square wave and both alarms.
1623 * For some variants, be sure alarms can trigger when we're
1624 * running on Vbackup (BBSQI/BBSQW)
1626 if (want_irq || ds1307_can_wakeup_device) {
1627 regs[0] |= DS1337_BIT_INTCN | chip->bbsqi_bit;
1628 regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
1631 regmap_write(ds1307->regmap, DS1337_REG_CONTROL,
1634 /* oscillator fault? clear flag, and warn */
1635 if (regs[1] & DS1337_BIT_OSF) {
1636 regmap_write(ds1307->regmap, DS1337_REG_STATUS,
1637 regs[1] & ~DS1337_BIT_OSF);
1638 dev_warn(ds1307->dev, "SET TIME!\n");
1643 err = regmap_bulk_read(ds1307->regmap,
1644 RX8025_REG_CTRL1 << 4 | 0x08, regs, 2);
1646 dev_dbg(ds1307->dev, "read error %d\n", err);
1650 /* oscillator off? turn it on, so clock can tick. */
1651 if (!(regs[1] & RX8025_BIT_XST)) {
1652 regs[1] |= RX8025_BIT_XST;
1653 regmap_write(ds1307->regmap,
1654 RX8025_REG_CTRL2 << 4 | 0x08,
1656 dev_warn(ds1307->dev,
1657 "oscillator stop detected - SET TIME!\n");
1660 if (regs[1] & RX8025_BIT_PON) {
1661 regs[1] &= ~RX8025_BIT_PON;
1662 regmap_write(ds1307->regmap,
1663 RX8025_REG_CTRL2 << 4 | 0x08,
1665 dev_warn(ds1307->dev, "power-on detected\n");
1668 if (regs[1] & RX8025_BIT_VDET) {
1669 regs[1] &= ~RX8025_BIT_VDET;
1670 regmap_write(ds1307->regmap,
1671 RX8025_REG_CTRL2 << 4 | 0x08,
1673 dev_warn(ds1307->dev, "voltage drop detected\n");
1676 /* make sure we are running in 24hour mode */
1677 if (!(regs[0] & RX8025_BIT_2412)) {
1680 /* switch to 24 hour mode */
1681 regmap_write(ds1307->regmap,
1682 RX8025_REG_CTRL1 << 4 | 0x08,
1683 regs[0] | RX8025_BIT_2412);
1685 err = regmap_bulk_read(ds1307->regmap,
1686 RX8025_REG_CTRL1 << 4 | 0x08,
1689 dev_dbg(ds1307->dev, "read error %d\n", err);
1694 hour = bcd2bin(regs[DS1307_REG_HOUR]);
1697 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1700 regmap_write(ds1307->regmap,
1701 DS1307_REG_HOUR << 4 | 0x08, hour);
1709 /* read RTC registers */
1710 err = regmap_bulk_read(ds1307->regmap, chip->offset, regs,
1713 dev_dbg(ds1307->dev, "read error %d\n", err);
1718 * minimal sanity checking; some chips (like DS1340) don't
1719 * specify the extra bits as must-be-zero, but there are
1720 * still a few values that are clearly out-of-range.
1722 tmp = regs[DS1307_REG_SECS];
1723 switch (ds1307->type) {
1728 /* clock halted? turn it on, so clock can tick. */
1729 if (tmp & DS1307_BIT_CH) {
1730 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1731 dev_warn(ds1307->dev, "SET TIME!\n");
1737 /* clock halted? turn it on, so clock can tick. */
1738 if (tmp & DS1307_BIT_CH)
1739 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1741 /* oscillator fault? clear flag, and warn */
1742 if (regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
1743 regmap_write(ds1307->regmap, DS1307_REG_CONTROL,
1744 regs[DS1307_REG_CONTROL] &
1746 dev_warn(ds1307->dev, "SET TIME!\n");
1751 /* clock halted? turn it on, so clock can tick. */
1752 if (tmp & DS1340_BIT_nEOSC)
1753 regmap_write(ds1307->regmap, DS1307_REG_SECS, 0);
1755 err = regmap_read(ds1307->regmap, DS1340_REG_FLAG, &tmp);
1757 dev_dbg(ds1307->dev, "read error %d\n", err);
1761 /* oscillator fault? clear flag, and warn */
1762 if (tmp & DS1340_BIT_OSF) {
1763 regmap_write(ds1307->regmap, DS1340_REG_FLAG, 0);
1764 dev_warn(ds1307->dev, "SET TIME!\n");
1768 /* make sure that the backup battery is enabled */
1769 if (!(regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
1770 regmap_write(ds1307->regmap, DS1307_REG_WDAY,
1771 regs[DS1307_REG_WDAY] |
1772 MCP794XX_BIT_VBATEN);
1775 /* clock halted? turn it on, so clock can tick. */
1776 if (!(tmp & MCP794XX_BIT_ST)) {
1777 regmap_write(ds1307->regmap, DS1307_REG_SECS,
1779 dev_warn(ds1307->dev, "SET TIME!\n");
1788 tmp = regs[DS1307_REG_HOUR];
1789 switch (ds1307->type) {
1795 * NOTE: ignores century bits; fix before deploying
1796 * systems that will run through year 2100.
1802 if (!(tmp & DS1307_BIT_12HR))
1806 * Be sure we're in 24 hour mode. Multi-master systems
1809 tmp = bcd2bin(tmp & 0x1f);
1812 if (regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1814 regmap_write(ds1307->regmap, chip->offset + DS1307_REG_HOUR,
1818 if (want_irq || ds1307_can_wakeup_device) {
1819 device_set_wakeup_capable(ds1307->dev, true);
1820 set_bit(HAS_ALARM, &ds1307->flags);
1823 ds1307->rtc = devm_rtc_allocate_device(ds1307->dev);
1824 if (IS_ERR(ds1307->rtc))
1825 return PTR_ERR(ds1307->rtc);
1827 if (ds1307_can_wakeup_device && !want_irq) {
1828 dev_info(ds1307->dev,
1829 "'wakeup-source' is set, request for an IRQ is disabled!\n");
1830 /* We cannot support UIE mode if we do not have an IRQ line */
1831 ds1307->rtc->uie_unsupported = 1;
1835 err = devm_request_threaded_irq(ds1307->dev, client->irq, NULL,
1836 chip->irq_handler ?: ds1307_irq,
1837 IRQF_SHARED | IRQF_ONESHOT,
1838 ds1307->name, ds1307);
1841 device_set_wakeup_capable(ds1307->dev, false);
1842 clear_bit(HAS_ALARM, &ds1307->flags);
1843 dev_err(ds1307->dev, "unable to request IRQ!\n");
1845 dev_dbg(ds1307->dev, "got IRQ %d\n", client->irq);
1849 ds1307->rtc->ops = chip->rtc_ops ?: &ds13xx_rtc_ops;
1850 err = ds1307_add_frequency_test(ds1307);
1854 err = rtc_register_device(ds1307->rtc);
1858 if (chip->nvram_size) {
1859 struct nvmem_config nvmem_cfg = {
1860 .name = "ds1307_nvram",
1863 .size = chip->nvram_size,
1864 .reg_read = ds1307_nvram_read,
1865 .reg_write = ds1307_nvram_write,
1869 ds1307->rtc->nvram_old_abi = true;
1870 rtc_nvmem_register(ds1307->rtc, &nvmem_cfg);
1873 ds1307_hwmon_register(ds1307);
1874 ds1307_clks_register(ds1307);
1882 static struct i2c_driver ds1307_driver = {
1884 .name = "rtc-ds1307",
1885 .of_match_table = of_match_ptr(ds1307_of_match),
1886 .acpi_match_table = ACPI_PTR(ds1307_acpi_ids),
1888 .probe = ds1307_probe,
1889 .id_table = ds1307_id,
1892 module_i2c_driver(ds1307_driver);
1894 MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1895 MODULE_LICENSE("GPL");