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[mirror_ubuntu-artful-kernel.git] / drivers / rtc / rtc-ds1307.c
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
28 /*
29 * We can't determine type by probing, but if we expect pre-Linux code
30 * to have set the chip up as a clock (turning on the oscillator and
31 * setting the date and time), Linux can ignore the non-clock features.
32 * That's a natural job for a factory or repair bench.
33 */
34 enum ds_type {
35 ds_1307,
36 ds_1337,
37 ds_1338,
38 ds_1339,
39 ds_1340,
40 ds_1388,
41 ds_3231,
42 m41t0,
43 m41t00,
44 mcp794xx,
45 rx_8025,
46 last_ds_type /* always last */
47 /* rs5c372 too? different address... */
48 };
49
50
51 /* RTC registers don't differ much, except for the century flag */
52 #define DS1307_REG_SECS 0x00 /* 00-59 */
53 # define DS1307_BIT_CH 0x80
54 # define DS1340_BIT_nEOSC 0x80
55 # define MCP794XX_BIT_ST 0x80
56 #define DS1307_REG_MIN 0x01 /* 00-59 */
57 # define M41T0_BIT_OF 0x80
58 #define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
59 # define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
60 # define DS1307_BIT_PM 0x20 /* in REG_HOUR */
61 # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
62 # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
63 #define DS1307_REG_WDAY 0x03 /* 01-07 */
64 # define MCP794XX_BIT_VBATEN 0x08
65 #define DS1307_REG_MDAY 0x04 /* 01-31 */
66 #define DS1307_REG_MONTH 0x05 /* 01-12 */
67 # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
68 #define DS1307_REG_YEAR 0x06 /* 00-99 */
69
70 /*
71 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
72 * start at 7, and they differ a LOT. Only control and status matter for
73 * basic RTC date and time functionality; be careful using them.
74 */
75 #define DS1307_REG_CONTROL 0x07 /* or ds1338 */
76 # define DS1307_BIT_OUT 0x80
77 # define DS1338_BIT_OSF 0x20
78 # define DS1307_BIT_SQWE 0x10
79 # define DS1307_BIT_RS1 0x02
80 # define DS1307_BIT_RS0 0x01
81 #define DS1337_REG_CONTROL 0x0e
82 # define DS1337_BIT_nEOSC 0x80
83 # define DS1339_BIT_BBSQI 0x20
84 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
85 # define DS1337_BIT_RS2 0x10
86 # define DS1337_BIT_RS1 0x08
87 # define DS1337_BIT_INTCN 0x04
88 # define DS1337_BIT_A2IE 0x02
89 # define DS1337_BIT_A1IE 0x01
90 #define DS1340_REG_CONTROL 0x07
91 # define DS1340_BIT_OUT 0x80
92 # define DS1340_BIT_FT 0x40
93 # define DS1340_BIT_CALIB_SIGN 0x20
94 # define DS1340_M_CALIBRATION 0x1f
95 #define DS1340_REG_FLAG 0x09
96 # define DS1340_BIT_OSF 0x80
97 #define DS1337_REG_STATUS 0x0f
98 # define DS1337_BIT_OSF 0x80
99 # define DS3231_BIT_EN32KHZ 0x08
100 # define DS1337_BIT_A2I 0x02
101 # define DS1337_BIT_A1I 0x01
102 #define DS1339_REG_ALARM1_SECS 0x07
103
104 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
105
106 #define RX8025_REG_CTRL1 0x0e
107 # define RX8025_BIT_2412 0x20
108 #define RX8025_REG_CTRL2 0x0f
109 # define RX8025_BIT_PON 0x10
110 # define RX8025_BIT_VDET 0x40
111 # define RX8025_BIT_XST 0x20
112
113
114 struct ds1307 {
115 u8 offset; /* register's offset */
116 u8 regs[11];
117 u16 nvram_offset;
118 struct bin_attribute *nvram;
119 enum ds_type type;
120 unsigned long flags;
121 #define HAS_NVRAM 0 /* bit 0 == sysfs file active */
122 #define HAS_ALARM 1 /* bit 1 == irq claimed */
123 struct i2c_client *client;
124 struct rtc_device *rtc;
125 s32 (*read_block_data)(const struct i2c_client *client, u8 command,
126 u8 length, u8 *values);
127 s32 (*write_block_data)(const struct i2c_client *client, u8 command,
128 u8 length, const u8 *values);
129 #ifdef CONFIG_COMMON_CLK
130 struct clk_hw clks[2];
131 #endif
132 };
133
134 struct chip_desc {
135 unsigned alarm:1;
136 u16 nvram_offset;
137 u16 nvram_size;
138 u16 trickle_charger_reg;
139 u8 trickle_charger_setup;
140 u8 (*do_trickle_setup)(struct i2c_client *, uint32_t, bool);
141 };
142
143 static u8 do_trickle_setup_ds1339(struct i2c_client *,
144 uint32_t ohms, bool diode);
145
146 static struct chip_desc chips[last_ds_type] = {
147 [ds_1307] = {
148 .nvram_offset = 8,
149 .nvram_size = 56,
150 },
151 [ds_1337] = {
152 .alarm = 1,
153 },
154 [ds_1338] = {
155 .nvram_offset = 8,
156 .nvram_size = 56,
157 },
158 [ds_1339] = {
159 .alarm = 1,
160 .trickle_charger_reg = 0x10,
161 .do_trickle_setup = &do_trickle_setup_ds1339,
162 },
163 [ds_1340] = {
164 .trickle_charger_reg = 0x08,
165 },
166 [ds_1388] = {
167 .trickle_charger_reg = 0x0a,
168 },
169 [ds_3231] = {
170 .alarm = 1,
171 },
172 [mcp794xx] = {
173 .alarm = 1,
174 /* this is battery backed SRAM */
175 .nvram_offset = 0x20,
176 .nvram_size = 0x40,
177 },
178 };
179
180 static const struct i2c_device_id ds1307_id[] = {
181 { "ds1307", ds_1307 },
182 { "ds1337", ds_1337 },
183 { "ds1338", ds_1338 },
184 { "ds1339", ds_1339 },
185 { "ds1388", ds_1388 },
186 { "ds1340", ds_1340 },
187 { "ds3231", ds_3231 },
188 { "m41t0", m41t0 },
189 { "m41t00", m41t00 },
190 { "mcp7940x", mcp794xx },
191 { "mcp7941x", mcp794xx },
192 { "pt7c4338", ds_1307 },
193 { "rx8025", rx_8025 },
194 { "isl12057", ds_1337 },
195 { }
196 };
197 MODULE_DEVICE_TABLE(i2c, ds1307_id);
198
199 #ifdef CONFIG_OF
200 static const struct of_device_id ds1307_of_match[] = {
201 {
202 .compatible = "dallas,ds1307",
203 .data = (void *)ds_1307
204 },
205 {
206 .compatible = "dallas,ds1337",
207 .data = (void *)ds_1337
208 },
209 {
210 .compatible = "dallas,ds1338",
211 .data = (void *)ds_1338
212 },
213 {
214 .compatible = "dallas,ds1339",
215 .data = (void *)ds_1339
216 },
217 {
218 .compatible = "dallas,ds1388",
219 .data = (void *)ds_1388
220 },
221 {
222 .compatible = "dallas,ds1340",
223 .data = (void *)ds_1340
224 },
225 {
226 .compatible = "maxim,ds3231",
227 .data = (void *)ds_3231
228 },
229 {
230 .compatible = "st,m41t0",
231 .data = (void *)m41t00
232 },
233 {
234 .compatible = "st,m41t00",
235 .data = (void *)m41t00
236 },
237 {
238 .compatible = "microchip,mcp7940x",
239 .data = (void *)mcp794xx
240 },
241 {
242 .compatible = "microchip,mcp7941x",
243 .data = (void *)mcp794xx
244 },
245 {
246 .compatible = "pericom,pt7c4338",
247 .data = (void *)ds_1307
248 },
249 {
250 .compatible = "epson,rx8025",
251 .data = (void *)rx_8025
252 },
253 {
254 .compatible = "isil,isl12057",
255 .data = (void *)ds_1337
256 },
257 { }
258 };
259 MODULE_DEVICE_TABLE(of, ds1307_of_match);
260 #endif
261
262 #ifdef CONFIG_ACPI
263 static const struct acpi_device_id ds1307_acpi_ids[] = {
264 { .id = "DS1307", .driver_data = ds_1307 },
265 { .id = "DS1337", .driver_data = ds_1337 },
266 { .id = "DS1338", .driver_data = ds_1338 },
267 { .id = "DS1339", .driver_data = ds_1339 },
268 { .id = "DS1388", .driver_data = ds_1388 },
269 { .id = "DS1340", .driver_data = ds_1340 },
270 { .id = "DS3231", .driver_data = ds_3231 },
271 { .id = "M41T0", .driver_data = m41t0 },
272 { .id = "M41T00", .driver_data = m41t00 },
273 { .id = "MCP7940X", .driver_data = mcp794xx },
274 { .id = "MCP7941X", .driver_data = mcp794xx },
275 { .id = "PT7C4338", .driver_data = ds_1307 },
276 { .id = "RX8025", .driver_data = rx_8025 },
277 { .id = "ISL12057", .driver_data = ds_1337 },
278 { }
279 };
280 MODULE_DEVICE_TABLE(acpi, ds1307_acpi_ids);
281 #endif
282
283 /*----------------------------------------------------------------------*/
284
285 #define BLOCK_DATA_MAX_TRIES 10
286
287 static s32 ds1307_read_block_data_once(const struct i2c_client *client,
288 u8 command, u8 length, u8 *values)
289 {
290 s32 i, data;
291
292 for (i = 0; i < length; i++) {
293 data = i2c_smbus_read_byte_data(client, command + i);
294 if (data < 0)
295 return data;
296 values[i] = data;
297 }
298 return i;
299 }
300
301 static s32 ds1307_read_block_data(const struct i2c_client *client, u8 command,
302 u8 length, u8 *values)
303 {
304 u8 oldvalues[255];
305 s32 ret;
306 int tries = 0;
307
308 dev_dbg(&client->dev, "ds1307_read_block_data (length=%d)\n", length);
309 ret = ds1307_read_block_data_once(client, command, length, values);
310 if (ret < 0)
311 return ret;
312 do {
313 if (++tries > BLOCK_DATA_MAX_TRIES) {
314 dev_err(&client->dev,
315 "ds1307_read_block_data failed\n");
316 return -EIO;
317 }
318 memcpy(oldvalues, values, length);
319 ret = ds1307_read_block_data_once(client, command, length,
320 values);
321 if (ret < 0)
322 return ret;
323 } while (memcmp(oldvalues, values, length));
324 return length;
325 }
326
327 static s32 ds1307_write_block_data(const struct i2c_client *client, u8 command,
328 u8 length, const u8 *values)
329 {
330 u8 currvalues[255];
331 int tries = 0;
332
333 dev_dbg(&client->dev, "ds1307_write_block_data (length=%d)\n", length);
334 do {
335 s32 i, ret;
336
337 if (++tries > BLOCK_DATA_MAX_TRIES) {
338 dev_err(&client->dev,
339 "ds1307_write_block_data failed\n");
340 return -EIO;
341 }
342 for (i = 0; i < length; i++) {
343 ret = i2c_smbus_write_byte_data(client, command + i,
344 values[i]);
345 if (ret < 0)
346 return ret;
347 }
348 ret = ds1307_read_block_data_once(client, command, length,
349 currvalues);
350 if (ret < 0)
351 return ret;
352 } while (memcmp(currvalues, values, length));
353 return length;
354 }
355
356 /*----------------------------------------------------------------------*/
357
358 /* These RTC devices are not designed to be connected to a SMbus adapter.
359 SMbus limits block operations length to 32 bytes, whereas it's not
360 limited on I2C buses. As a result, accesses may exceed 32 bytes;
361 in that case, split them into smaller blocks */
362
363 static s32 ds1307_native_smbus_write_block_data(const struct i2c_client *client,
364 u8 command, u8 length, const u8 *values)
365 {
366 u8 suboffset = 0;
367
368 if (length <= I2C_SMBUS_BLOCK_MAX) {
369 s32 retval = i2c_smbus_write_i2c_block_data(client,
370 command, length, values);
371 if (retval < 0)
372 return retval;
373 return length;
374 }
375
376 while (suboffset < length) {
377 s32 retval = i2c_smbus_write_i2c_block_data(client,
378 command + suboffset,
379 min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
380 values + suboffset);
381 if (retval < 0)
382 return retval;
383
384 suboffset += I2C_SMBUS_BLOCK_MAX;
385 }
386 return length;
387 }
388
389 static s32 ds1307_native_smbus_read_block_data(const struct i2c_client *client,
390 u8 command, u8 length, u8 *values)
391 {
392 u8 suboffset = 0;
393
394 if (length <= I2C_SMBUS_BLOCK_MAX)
395 return i2c_smbus_read_i2c_block_data(client,
396 command, length, values);
397
398 while (suboffset < length) {
399 s32 retval = i2c_smbus_read_i2c_block_data(client,
400 command + suboffset,
401 min(I2C_SMBUS_BLOCK_MAX, length - suboffset),
402 values + suboffset);
403 if (retval < 0)
404 return retval;
405
406 suboffset += I2C_SMBUS_BLOCK_MAX;
407 }
408 return length;
409 }
410
411 /*----------------------------------------------------------------------*/
412
413 /*
414 * The ds1337 and ds1339 both have two alarms, but we only use the first
415 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
416 * signal; ds1339 chips have only one alarm signal.
417 */
418 static irqreturn_t ds1307_irq(int irq, void *dev_id)
419 {
420 struct i2c_client *client = dev_id;
421 struct ds1307 *ds1307 = i2c_get_clientdata(client);
422 struct mutex *lock = &ds1307->rtc->ops_lock;
423 int stat, control;
424
425 mutex_lock(lock);
426 stat = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);
427 if (stat < 0)
428 goto out;
429
430 if (stat & DS1337_BIT_A1I) {
431 stat &= ~DS1337_BIT_A1I;
432 i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, stat);
433
434 control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
435 if (control < 0)
436 goto out;
437
438 control &= ~DS1337_BIT_A1IE;
439 i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
440
441 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
442 }
443
444 out:
445 mutex_unlock(lock);
446
447 return IRQ_HANDLED;
448 }
449
450 /*----------------------------------------------------------------------*/
451
452 static int ds1307_get_time(struct device *dev, struct rtc_time *t)
453 {
454 struct ds1307 *ds1307 = dev_get_drvdata(dev);
455 int tmp;
456
457 /* read the RTC date and time registers all at once */
458 tmp = ds1307->read_block_data(ds1307->client,
459 ds1307->offset, 7, ds1307->regs);
460 if (tmp != 7) {
461 dev_err(dev, "%s error %d\n", "read", tmp);
462 return -EIO;
463 }
464
465 dev_dbg(dev, "%s: %7ph\n", "read", ds1307->regs);
466
467 /* if oscillator fail bit is set, no data can be trusted */
468 if (ds1307->type == m41t0 &&
469 ds1307->regs[DS1307_REG_MIN] & M41T0_BIT_OF) {
470 dev_warn_once(dev, "oscillator failed, set time!\n");
471 return -EINVAL;
472 }
473
474 t->tm_sec = bcd2bin(ds1307->regs[DS1307_REG_SECS] & 0x7f);
475 t->tm_min = bcd2bin(ds1307->regs[DS1307_REG_MIN] & 0x7f);
476 tmp = ds1307->regs[DS1307_REG_HOUR] & 0x3f;
477 t->tm_hour = bcd2bin(tmp);
478 t->tm_wday = bcd2bin(ds1307->regs[DS1307_REG_WDAY] & 0x07) - 1;
479 t->tm_mday = bcd2bin(ds1307->regs[DS1307_REG_MDAY] & 0x3f);
480 tmp = ds1307->regs[DS1307_REG_MONTH] & 0x1f;
481 t->tm_mon = bcd2bin(tmp) - 1;
482 t->tm_year = bcd2bin(ds1307->regs[DS1307_REG_YEAR]) + 100;
483
484 #ifdef CONFIG_RTC_DRV_DS1307_CENTURY
485 switch (ds1307->type) {
486 case ds_1337:
487 case ds_1339:
488 case ds_3231:
489 if (ds1307->regs[DS1307_REG_MONTH] & DS1337_BIT_CENTURY)
490 t->tm_year += 100;
491 break;
492 case ds_1340:
493 if (ds1307->regs[DS1307_REG_HOUR] & DS1340_BIT_CENTURY)
494 t->tm_year += 100;
495 break;
496 default:
497 break;
498 }
499 #endif
500
501 dev_dbg(dev, "%s secs=%d, mins=%d, "
502 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
503 "read", t->tm_sec, t->tm_min,
504 t->tm_hour, t->tm_mday,
505 t->tm_mon, t->tm_year, t->tm_wday);
506
507 /* initial clock setting can be undefined */
508 return rtc_valid_tm(t);
509 }
510
511 static int ds1307_set_time(struct device *dev, struct rtc_time *t)
512 {
513 struct ds1307 *ds1307 = dev_get_drvdata(dev);
514 int result;
515 int tmp;
516 u8 *buf = ds1307->regs;
517
518 dev_dbg(dev, "%s secs=%d, mins=%d, "
519 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
520 "write", t->tm_sec, t->tm_min,
521 t->tm_hour, t->tm_mday,
522 t->tm_mon, t->tm_year, t->tm_wday);
523
524 #ifdef CONFIG_RTC_DRV_DS1307_CENTURY
525 if (t->tm_year < 100)
526 return -EINVAL;
527
528 switch (ds1307->type) {
529 case ds_1337:
530 case ds_1339:
531 case ds_3231:
532 case ds_1340:
533 if (t->tm_year > 299)
534 return -EINVAL;
535 default:
536 if (t->tm_year > 199)
537 return -EINVAL;
538 break;
539 }
540 #else
541 if (t->tm_year < 100 || t->tm_year > 199)
542 return -EINVAL;
543 #endif
544
545 buf[DS1307_REG_SECS] = bin2bcd(t->tm_sec);
546 buf[DS1307_REG_MIN] = bin2bcd(t->tm_min);
547 buf[DS1307_REG_HOUR] = bin2bcd(t->tm_hour);
548 buf[DS1307_REG_WDAY] = bin2bcd(t->tm_wday + 1);
549 buf[DS1307_REG_MDAY] = bin2bcd(t->tm_mday);
550 buf[DS1307_REG_MONTH] = bin2bcd(t->tm_mon + 1);
551
552 /* assume 20YY not 19YY */
553 tmp = t->tm_year - 100;
554 buf[DS1307_REG_YEAR] = bin2bcd(tmp);
555
556 switch (ds1307->type) {
557 case ds_1337:
558 case ds_1339:
559 case ds_3231:
560 if (t->tm_year > 199)
561 buf[DS1307_REG_MONTH] |= DS1337_BIT_CENTURY;
562 break;
563 case ds_1340:
564 buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY_EN;
565 if (t->tm_year > 199)
566 buf[DS1307_REG_HOUR] |= DS1340_BIT_CENTURY;
567 break;
568 case mcp794xx:
569 /*
570 * these bits were cleared when preparing the date/time
571 * values and need to be set again before writing the
572 * buffer out to the device.
573 */
574 buf[DS1307_REG_SECS] |= MCP794XX_BIT_ST;
575 buf[DS1307_REG_WDAY] |= MCP794XX_BIT_VBATEN;
576 break;
577 default:
578 break;
579 }
580
581 dev_dbg(dev, "%s: %7ph\n", "write", buf);
582
583 result = ds1307->write_block_data(ds1307->client,
584 ds1307->offset, 7, buf);
585 if (result < 0) {
586 dev_err(dev, "%s error %d\n", "write", result);
587 return result;
588 }
589 return 0;
590 }
591
592 static int ds1337_read_alarm(struct device *dev, struct rtc_wkalrm *t)
593 {
594 struct i2c_client *client = to_i2c_client(dev);
595 struct ds1307 *ds1307 = i2c_get_clientdata(client);
596 int ret;
597
598 if (!test_bit(HAS_ALARM, &ds1307->flags))
599 return -EINVAL;
600
601 /* read all ALARM1, ALARM2, and status registers at once */
602 ret = ds1307->read_block_data(client,
603 DS1339_REG_ALARM1_SECS, 9, ds1307->regs);
604 if (ret != 9) {
605 dev_err(dev, "%s error %d\n", "alarm read", ret);
606 return -EIO;
607 }
608
609 dev_dbg(dev, "%s: %4ph, %3ph, %2ph\n", "alarm read",
610 &ds1307->regs[0], &ds1307->regs[4], &ds1307->regs[7]);
611
612 /*
613 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
614 * and that all four fields are checked matches
615 */
616 t->time.tm_sec = bcd2bin(ds1307->regs[0] & 0x7f);
617 t->time.tm_min = bcd2bin(ds1307->regs[1] & 0x7f);
618 t->time.tm_hour = bcd2bin(ds1307->regs[2] & 0x3f);
619 t->time.tm_mday = bcd2bin(ds1307->regs[3] & 0x3f);
620
621 /* ... and status */
622 t->enabled = !!(ds1307->regs[7] & DS1337_BIT_A1IE);
623 t->pending = !!(ds1307->regs[8] & DS1337_BIT_A1I);
624
625 dev_dbg(dev, "%s secs=%d, mins=%d, "
626 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
627 "alarm read", t->time.tm_sec, t->time.tm_min,
628 t->time.tm_hour, t->time.tm_mday,
629 t->enabled, t->pending);
630
631 return 0;
632 }
633
634 static int ds1337_set_alarm(struct device *dev, struct rtc_wkalrm *t)
635 {
636 struct i2c_client *client = to_i2c_client(dev);
637 struct ds1307 *ds1307 = i2c_get_clientdata(client);
638 unsigned char *buf = ds1307->regs;
639 u8 control, status;
640 int ret;
641
642 if (!test_bit(HAS_ALARM, &ds1307->flags))
643 return -EINVAL;
644
645 dev_dbg(dev, "%s secs=%d, mins=%d, "
646 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
647 "alarm set", t->time.tm_sec, t->time.tm_min,
648 t->time.tm_hour, t->time.tm_mday,
649 t->enabled, t->pending);
650
651 /* read current status of both alarms and the chip */
652 ret = ds1307->read_block_data(client,
653 DS1339_REG_ALARM1_SECS, 9, buf);
654 if (ret != 9) {
655 dev_err(dev, "%s error %d\n", "alarm write", ret);
656 return -EIO;
657 }
658 control = ds1307->regs[7];
659 status = ds1307->regs[8];
660
661 dev_dbg(dev, "%s: %4ph, %3ph, %02x %02x\n", "alarm set (old status)",
662 &ds1307->regs[0], &ds1307->regs[4], control, status);
663
664 /* set ALARM1, using 24 hour and day-of-month modes */
665 buf[0] = bin2bcd(t->time.tm_sec);
666 buf[1] = bin2bcd(t->time.tm_min);
667 buf[2] = bin2bcd(t->time.tm_hour);
668 buf[3] = bin2bcd(t->time.tm_mday);
669
670 /* set ALARM2 to non-garbage */
671 buf[4] = 0;
672 buf[5] = 0;
673 buf[6] = 0;
674
675 /* disable alarms */
676 buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
677 buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
678
679 ret = ds1307->write_block_data(client,
680 DS1339_REG_ALARM1_SECS, 9, buf);
681 if (ret < 0) {
682 dev_err(dev, "can't set alarm time\n");
683 return ret;
684 }
685
686 /* optionally enable ALARM1 */
687 if (t->enabled) {
688 dev_dbg(dev, "alarm IRQ armed\n");
689 buf[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
690 i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, buf[7]);
691 }
692
693 return 0;
694 }
695
696 static int ds1307_alarm_irq_enable(struct device *dev, unsigned int enabled)
697 {
698 struct i2c_client *client = to_i2c_client(dev);
699 struct ds1307 *ds1307 = i2c_get_clientdata(client);
700 int ret;
701
702 if (!test_bit(HAS_ALARM, &ds1307->flags))
703 return -ENOTTY;
704
705 ret = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
706 if (ret < 0)
707 return ret;
708
709 if (enabled)
710 ret |= DS1337_BIT_A1IE;
711 else
712 ret &= ~DS1337_BIT_A1IE;
713
714 ret = i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, ret);
715 if (ret < 0)
716 return ret;
717
718 return 0;
719 }
720
721 static const struct rtc_class_ops ds13xx_rtc_ops = {
722 .read_time = ds1307_get_time,
723 .set_time = ds1307_set_time,
724 .read_alarm = ds1337_read_alarm,
725 .set_alarm = ds1337_set_alarm,
726 .alarm_irq_enable = ds1307_alarm_irq_enable,
727 };
728
729 /*----------------------------------------------------------------------*/
730
731 /*
732 * Alarm support for mcp794xx devices.
733 */
734
735 #define MCP794XX_REG_WEEKDAY 0x3
736 #define MCP794XX_REG_WEEKDAY_WDAY_MASK 0x7
737 #define MCP794XX_REG_CONTROL 0x07
738 # define MCP794XX_BIT_ALM0_EN 0x10
739 # define MCP794XX_BIT_ALM1_EN 0x20
740 #define MCP794XX_REG_ALARM0_BASE 0x0a
741 #define MCP794XX_REG_ALARM0_CTRL 0x0d
742 #define MCP794XX_REG_ALARM1_BASE 0x11
743 #define MCP794XX_REG_ALARM1_CTRL 0x14
744 # define MCP794XX_BIT_ALMX_IF (1 << 3)
745 # define MCP794XX_BIT_ALMX_C0 (1 << 4)
746 # define MCP794XX_BIT_ALMX_C1 (1 << 5)
747 # define MCP794XX_BIT_ALMX_C2 (1 << 6)
748 # define MCP794XX_BIT_ALMX_POL (1 << 7)
749 # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
750 MCP794XX_BIT_ALMX_C1 | \
751 MCP794XX_BIT_ALMX_C2)
752
753 static irqreturn_t mcp794xx_irq(int irq, void *dev_id)
754 {
755 struct i2c_client *client = dev_id;
756 struct ds1307 *ds1307 = i2c_get_clientdata(client);
757 struct mutex *lock = &ds1307->rtc->ops_lock;
758 int reg, ret;
759
760 mutex_lock(lock);
761
762 /* Check and clear alarm 0 interrupt flag. */
763 reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_ALARM0_CTRL);
764 if (reg < 0)
765 goto out;
766 if (!(reg & MCP794XX_BIT_ALMX_IF))
767 goto out;
768 reg &= ~MCP794XX_BIT_ALMX_IF;
769 ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_ALARM0_CTRL, reg);
770 if (ret < 0)
771 goto out;
772
773 /* Disable alarm 0. */
774 reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);
775 if (reg < 0)
776 goto out;
777 reg &= ~MCP794XX_BIT_ALM0_EN;
778 ret = i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);
779 if (ret < 0)
780 goto out;
781
782 rtc_update_irq(ds1307->rtc, 1, RTC_AF | RTC_IRQF);
783
784 out:
785 mutex_unlock(lock);
786
787 return IRQ_HANDLED;
788 }
789
790 static int mcp794xx_read_alarm(struct device *dev, struct rtc_wkalrm *t)
791 {
792 struct i2c_client *client = to_i2c_client(dev);
793 struct ds1307 *ds1307 = i2c_get_clientdata(client);
794 u8 *regs = ds1307->regs;
795 int ret;
796
797 if (!test_bit(HAS_ALARM, &ds1307->flags))
798 return -EINVAL;
799
800 /* Read control and alarm 0 registers. */
801 ret = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
802 if (ret < 0)
803 return ret;
804
805 t->enabled = !!(regs[0] & MCP794XX_BIT_ALM0_EN);
806
807 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
808 t->time.tm_sec = bcd2bin(ds1307->regs[3] & 0x7f);
809 t->time.tm_min = bcd2bin(ds1307->regs[4] & 0x7f);
810 t->time.tm_hour = bcd2bin(ds1307->regs[5] & 0x3f);
811 t->time.tm_wday = bcd2bin(ds1307->regs[6] & 0x7) - 1;
812 t->time.tm_mday = bcd2bin(ds1307->regs[7] & 0x3f);
813 t->time.tm_mon = bcd2bin(ds1307->regs[8] & 0x1f) - 1;
814 t->time.tm_year = -1;
815 t->time.tm_yday = -1;
816 t->time.tm_isdst = -1;
817
818 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
819 "enabled=%d polarity=%d irq=%d match=%d\n", __func__,
820 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
821 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon, t->enabled,
822 !!(ds1307->regs[6] & MCP794XX_BIT_ALMX_POL),
823 !!(ds1307->regs[6] & MCP794XX_BIT_ALMX_IF),
824 (ds1307->regs[6] & MCP794XX_MSK_ALMX_MATCH) >> 4);
825
826 return 0;
827 }
828
829 static int mcp794xx_set_alarm(struct device *dev, struct rtc_wkalrm *t)
830 {
831 struct i2c_client *client = to_i2c_client(dev);
832 struct ds1307 *ds1307 = i2c_get_clientdata(client);
833 unsigned char *regs = ds1307->regs;
834 int ret;
835
836 if (!test_bit(HAS_ALARM, &ds1307->flags))
837 return -EINVAL;
838
839 dev_dbg(dev, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
840 "enabled=%d pending=%d\n", __func__,
841 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
842 t->time.tm_wday, t->time.tm_mday, t->time.tm_mon,
843 t->enabled, t->pending);
844
845 /* Read control and alarm 0 registers. */
846 ret = ds1307->read_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
847 if (ret < 0)
848 return ret;
849
850 /* Set alarm 0, using 24-hour and day-of-month modes. */
851 regs[3] = bin2bcd(t->time.tm_sec);
852 regs[4] = bin2bcd(t->time.tm_min);
853 regs[5] = bin2bcd(t->time.tm_hour);
854 regs[6] = bin2bcd(t->time.tm_wday + 1);
855 regs[7] = bin2bcd(t->time.tm_mday);
856 regs[8] = bin2bcd(t->time.tm_mon + 1);
857
858 /* Clear the alarm 0 interrupt flag. */
859 regs[6] &= ~MCP794XX_BIT_ALMX_IF;
860 /* Set alarm match: second, minute, hour, day, date, month. */
861 regs[6] |= MCP794XX_MSK_ALMX_MATCH;
862 /* Disable interrupt. We will not enable until completely programmed */
863 regs[0] &= ~MCP794XX_BIT_ALM0_EN;
864
865 ret = ds1307->write_block_data(client, MCP794XX_REG_CONTROL, 10, regs);
866 if (ret < 0)
867 return ret;
868
869 if (!t->enabled)
870 return 0;
871 regs[0] |= MCP794XX_BIT_ALM0_EN;
872 return i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, regs[0]);
873 }
874
875 static int mcp794xx_alarm_irq_enable(struct device *dev, unsigned int enabled)
876 {
877 struct i2c_client *client = to_i2c_client(dev);
878 struct ds1307 *ds1307 = i2c_get_clientdata(client);
879 int reg;
880
881 if (!test_bit(HAS_ALARM, &ds1307->flags))
882 return -EINVAL;
883
884 reg = i2c_smbus_read_byte_data(client, MCP794XX_REG_CONTROL);
885 if (reg < 0)
886 return reg;
887
888 if (enabled)
889 reg |= MCP794XX_BIT_ALM0_EN;
890 else
891 reg &= ~MCP794XX_BIT_ALM0_EN;
892
893 return i2c_smbus_write_byte_data(client, MCP794XX_REG_CONTROL, reg);
894 }
895
896 static const struct rtc_class_ops mcp794xx_rtc_ops = {
897 .read_time = ds1307_get_time,
898 .set_time = ds1307_set_time,
899 .read_alarm = mcp794xx_read_alarm,
900 .set_alarm = mcp794xx_set_alarm,
901 .alarm_irq_enable = mcp794xx_alarm_irq_enable,
902 };
903
904 /*----------------------------------------------------------------------*/
905
906 static ssize_t
907 ds1307_nvram_read(struct file *filp, struct kobject *kobj,
908 struct bin_attribute *attr,
909 char *buf, loff_t off, size_t count)
910 {
911 struct i2c_client *client;
912 struct ds1307 *ds1307;
913 int result;
914
915 client = kobj_to_i2c_client(kobj);
916 ds1307 = i2c_get_clientdata(client);
917
918 result = ds1307->read_block_data(client, ds1307->nvram_offset + off,
919 count, buf);
920 if (result < 0)
921 dev_err(&client->dev, "%s error %d\n", "nvram read", result);
922 return result;
923 }
924
925 static ssize_t
926 ds1307_nvram_write(struct file *filp, struct kobject *kobj,
927 struct bin_attribute *attr,
928 char *buf, loff_t off, size_t count)
929 {
930 struct i2c_client *client;
931 struct ds1307 *ds1307;
932 int result;
933
934 client = kobj_to_i2c_client(kobj);
935 ds1307 = i2c_get_clientdata(client);
936
937 result = ds1307->write_block_data(client, ds1307->nvram_offset + off,
938 count, buf);
939 if (result < 0) {
940 dev_err(&client->dev, "%s error %d\n", "nvram write", result);
941 return result;
942 }
943 return count;
944 }
945
946
947 /*----------------------------------------------------------------------*/
948
949 static u8 do_trickle_setup_ds1339(struct i2c_client *client,
950 uint32_t ohms, bool diode)
951 {
952 u8 setup = (diode) ? DS1307_TRICKLE_CHARGER_DIODE :
953 DS1307_TRICKLE_CHARGER_NO_DIODE;
954
955 switch (ohms) {
956 case 250:
957 setup |= DS1307_TRICKLE_CHARGER_250_OHM;
958 break;
959 case 2000:
960 setup |= DS1307_TRICKLE_CHARGER_2K_OHM;
961 break;
962 case 4000:
963 setup |= DS1307_TRICKLE_CHARGER_4K_OHM;
964 break;
965 default:
966 dev_warn(&client->dev,
967 "Unsupported ohm value %u in dt\n", ohms);
968 return 0;
969 }
970 return setup;
971 }
972
973 static void ds1307_trickle_init(struct i2c_client *client,
974 struct chip_desc *chip)
975 {
976 uint32_t ohms = 0;
977 bool diode = true;
978
979 if (!chip->do_trickle_setup)
980 goto out;
981 if (device_property_read_u32(&client->dev, "trickle-resistor-ohms", &ohms))
982 goto out;
983 if (device_property_read_bool(&client->dev, "trickle-diode-disable"))
984 diode = false;
985 chip->trickle_charger_setup = chip->do_trickle_setup(client,
986 ohms, diode);
987 out:
988 return;
989 }
990
991 /*----------------------------------------------------------------------*/
992
993 #ifdef CONFIG_RTC_DRV_DS1307_HWMON
994
995 /*
996 * Temperature sensor support for ds3231 devices.
997 */
998
999 #define DS3231_REG_TEMPERATURE 0x11
1000
1001 /*
1002 * A user-initiated temperature conversion is not started by this function,
1003 * so the temperature is updated once every 64 seconds.
1004 */
1005 static int ds3231_hwmon_read_temp(struct device *dev, s32 *mC)
1006 {
1007 struct ds1307 *ds1307 = dev_get_drvdata(dev);
1008 u8 temp_buf[2];
1009 s16 temp;
1010 int ret;
1011
1012 ret = ds1307->read_block_data(ds1307->client, DS3231_REG_TEMPERATURE,
1013 sizeof(temp_buf), temp_buf);
1014 if (ret < 0)
1015 return ret;
1016 if (ret != sizeof(temp_buf))
1017 return -EIO;
1018
1019 /*
1020 * Temperature is represented as a 10-bit code with a resolution of
1021 * 0.25 degree celsius and encoded in two's complement format.
1022 */
1023 temp = (temp_buf[0] << 8) | temp_buf[1];
1024 temp >>= 6;
1025 *mC = temp * 250;
1026
1027 return 0;
1028 }
1029
1030 static ssize_t ds3231_hwmon_show_temp(struct device *dev,
1031 struct device_attribute *attr, char *buf)
1032 {
1033 int ret;
1034 s32 temp;
1035
1036 ret = ds3231_hwmon_read_temp(dev, &temp);
1037 if (ret)
1038 return ret;
1039
1040 return sprintf(buf, "%d\n", temp);
1041 }
1042 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ds3231_hwmon_show_temp,
1043 NULL, 0);
1044
1045 static struct attribute *ds3231_hwmon_attrs[] = {
1046 &sensor_dev_attr_temp1_input.dev_attr.attr,
1047 NULL,
1048 };
1049 ATTRIBUTE_GROUPS(ds3231_hwmon);
1050
1051 static void ds1307_hwmon_register(struct ds1307 *ds1307)
1052 {
1053 struct device *dev;
1054
1055 if (ds1307->type != ds_3231)
1056 return;
1057
1058 dev = devm_hwmon_device_register_with_groups(&ds1307->client->dev,
1059 ds1307->client->name,
1060 ds1307, ds3231_hwmon_groups);
1061 if (IS_ERR(dev)) {
1062 dev_warn(&ds1307->client->dev,
1063 "unable to register hwmon device %ld\n", PTR_ERR(dev));
1064 }
1065 }
1066
1067 #else
1068
1069 static void ds1307_hwmon_register(struct ds1307 *ds1307)
1070 {
1071 }
1072
1073 #endif /* CONFIG_RTC_DRV_DS1307_HWMON */
1074
1075 /*----------------------------------------------------------------------*/
1076
1077 /*
1078 * Square-wave output support for DS3231
1079 * Datasheet: https://datasheets.maximintegrated.com/en/ds/DS3231.pdf
1080 */
1081 #ifdef CONFIG_COMMON_CLK
1082
1083 enum {
1084 DS3231_CLK_SQW = 0,
1085 DS3231_CLK_32KHZ,
1086 };
1087
1088 #define clk_sqw_to_ds1307(clk) \
1089 container_of(clk, struct ds1307, clks[DS3231_CLK_SQW])
1090 #define clk_32khz_to_ds1307(clk) \
1091 container_of(clk, struct ds1307, clks[DS3231_CLK_32KHZ])
1092
1093 static int ds3231_clk_sqw_rates[] = {
1094 1,
1095 1024,
1096 4096,
1097 8192,
1098 };
1099
1100 static int ds1337_write_control(struct ds1307 *ds1307, u8 mask, u8 value)
1101 {
1102 struct i2c_client *client = ds1307->client;
1103 struct mutex *lock = &ds1307->rtc->ops_lock;
1104 int control;
1105 int ret;
1106
1107 mutex_lock(lock);
1108
1109 control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);
1110 if (control < 0) {
1111 ret = control;
1112 goto out;
1113 }
1114
1115 control &= ~mask;
1116 control |= value;
1117
1118 ret = i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, control);
1119 out:
1120 mutex_unlock(lock);
1121
1122 return ret;
1123 }
1124
1125 static unsigned long ds3231_clk_sqw_recalc_rate(struct clk_hw *hw,
1126 unsigned long parent_rate)
1127 {
1128 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1129 int control;
1130 int rate_sel = 0;
1131
1132 control = i2c_smbus_read_byte_data(ds1307->client, DS1337_REG_CONTROL);
1133 if (control < 0)
1134 return control;
1135 if (control & DS1337_BIT_RS1)
1136 rate_sel += 1;
1137 if (control & DS1337_BIT_RS2)
1138 rate_sel += 2;
1139
1140 return ds3231_clk_sqw_rates[rate_sel];
1141 }
1142
1143 static long ds3231_clk_sqw_round_rate(struct clk_hw *hw, unsigned long rate,
1144 unsigned long *prate)
1145 {
1146 int i;
1147
1148 for (i = ARRAY_SIZE(ds3231_clk_sqw_rates) - 1; i >= 0; i--) {
1149 if (ds3231_clk_sqw_rates[i] <= rate)
1150 return ds3231_clk_sqw_rates[i];
1151 }
1152
1153 return 0;
1154 }
1155
1156 static int ds3231_clk_sqw_set_rate(struct clk_hw *hw, unsigned long rate,
1157 unsigned long parent_rate)
1158 {
1159 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1160 int control = 0;
1161 int rate_sel;
1162
1163 for (rate_sel = 0; rate_sel < ARRAY_SIZE(ds3231_clk_sqw_rates);
1164 rate_sel++) {
1165 if (ds3231_clk_sqw_rates[rate_sel] == rate)
1166 break;
1167 }
1168
1169 if (rate_sel == ARRAY_SIZE(ds3231_clk_sqw_rates))
1170 return -EINVAL;
1171
1172 if (rate_sel & 1)
1173 control |= DS1337_BIT_RS1;
1174 if (rate_sel & 2)
1175 control |= DS1337_BIT_RS2;
1176
1177 return ds1337_write_control(ds1307, DS1337_BIT_RS1 | DS1337_BIT_RS2,
1178 control);
1179 }
1180
1181 static int ds3231_clk_sqw_prepare(struct clk_hw *hw)
1182 {
1183 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1184
1185 return ds1337_write_control(ds1307, DS1337_BIT_INTCN, 0);
1186 }
1187
1188 static void ds3231_clk_sqw_unprepare(struct clk_hw *hw)
1189 {
1190 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1191
1192 ds1337_write_control(ds1307, DS1337_BIT_INTCN, DS1337_BIT_INTCN);
1193 }
1194
1195 static int ds3231_clk_sqw_is_prepared(struct clk_hw *hw)
1196 {
1197 struct ds1307 *ds1307 = clk_sqw_to_ds1307(hw);
1198 int control;
1199
1200 control = i2c_smbus_read_byte_data(ds1307->client, DS1337_REG_CONTROL);
1201 if (control < 0)
1202 return control;
1203
1204 return !(control & DS1337_BIT_INTCN);
1205 }
1206
1207 static const struct clk_ops ds3231_clk_sqw_ops = {
1208 .prepare = ds3231_clk_sqw_prepare,
1209 .unprepare = ds3231_clk_sqw_unprepare,
1210 .is_prepared = ds3231_clk_sqw_is_prepared,
1211 .recalc_rate = ds3231_clk_sqw_recalc_rate,
1212 .round_rate = ds3231_clk_sqw_round_rate,
1213 .set_rate = ds3231_clk_sqw_set_rate,
1214 };
1215
1216 static unsigned long ds3231_clk_32khz_recalc_rate(struct clk_hw *hw,
1217 unsigned long parent_rate)
1218 {
1219 return 32768;
1220 }
1221
1222 static int ds3231_clk_32khz_control(struct ds1307 *ds1307, bool enable)
1223 {
1224 struct i2c_client *client = ds1307->client;
1225 struct mutex *lock = &ds1307->rtc->ops_lock;
1226 int status;
1227 int ret;
1228
1229 mutex_lock(lock);
1230
1231 status = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);
1232 if (status < 0) {
1233 ret = status;
1234 goto out;
1235 }
1236
1237 if (enable)
1238 status |= DS3231_BIT_EN32KHZ;
1239 else
1240 status &= ~DS3231_BIT_EN32KHZ;
1241
1242 ret = i2c_smbus_write_byte_data(client, DS1337_REG_STATUS, status);
1243 out:
1244 mutex_unlock(lock);
1245
1246 return ret;
1247 }
1248
1249 static int ds3231_clk_32khz_prepare(struct clk_hw *hw)
1250 {
1251 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1252
1253 return ds3231_clk_32khz_control(ds1307, true);
1254 }
1255
1256 static void ds3231_clk_32khz_unprepare(struct clk_hw *hw)
1257 {
1258 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1259
1260 ds3231_clk_32khz_control(ds1307, false);
1261 }
1262
1263 static int ds3231_clk_32khz_is_prepared(struct clk_hw *hw)
1264 {
1265 struct ds1307 *ds1307 = clk_32khz_to_ds1307(hw);
1266 int status;
1267
1268 status = i2c_smbus_read_byte_data(ds1307->client, DS1337_REG_STATUS);
1269 if (status < 0)
1270 return status;
1271
1272 return !!(status & DS3231_BIT_EN32KHZ);
1273 }
1274
1275 static const struct clk_ops ds3231_clk_32khz_ops = {
1276 .prepare = ds3231_clk_32khz_prepare,
1277 .unprepare = ds3231_clk_32khz_unprepare,
1278 .is_prepared = ds3231_clk_32khz_is_prepared,
1279 .recalc_rate = ds3231_clk_32khz_recalc_rate,
1280 };
1281
1282 static struct clk_init_data ds3231_clks_init[] = {
1283 [DS3231_CLK_SQW] = {
1284 .name = "ds3231_clk_sqw",
1285 .ops = &ds3231_clk_sqw_ops,
1286 },
1287 [DS3231_CLK_32KHZ] = {
1288 .name = "ds3231_clk_32khz",
1289 .ops = &ds3231_clk_32khz_ops,
1290 },
1291 };
1292
1293 static int ds3231_clks_register(struct ds1307 *ds1307)
1294 {
1295 struct i2c_client *client = ds1307->client;
1296 struct device_node *node = client->dev.of_node;
1297 struct clk_onecell_data *onecell;
1298 int i;
1299
1300 onecell = devm_kzalloc(&client->dev, sizeof(*onecell), GFP_KERNEL);
1301 if (!onecell)
1302 return -ENOMEM;
1303
1304 onecell->clk_num = ARRAY_SIZE(ds3231_clks_init);
1305 onecell->clks = devm_kcalloc(&client->dev, onecell->clk_num,
1306 sizeof(onecell->clks[0]), GFP_KERNEL);
1307 if (!onecell->clks)
1308 return -ENOMEM;
1309
1310 for (i = 0; i < ARRAY_SIZE(ds3231_clks_init); i++) {
1311 struct clk_init_data init = ds3231_clks_init[i];
1312
1313 /*
1314 * Interrupt signal due to alarm conditions and square-wave
1315 * output share same pin, so don't initialize both.
1316 */
1317 if (i == DS3231_CLK_SQW && test_bit(HAS_ALARM, &ds1307->flags))
1318 continue;
1319
1320 /* optional override of the clockname */
1321 of_property_read_string_index(node, "clock-output-names", i,
1322 &init.name);
1323 ds1307->clks[i].init = &init;
1324
1325 onecell->clks[i] = devm_clk_register(&client->dev,
1326 &ds1307->clks[i]);
1327 if (IS_ERR(onecell->clks[i]))
1328 return PTR_ERR(onecell->clks[i]);
1329 }
1330
1331 if (!node)
1332 return 0;
1333
1334 of_clk_add_provider(node, of_clk_src_onecell_get, onecell);
1335
1336 return 0;
1337 }
1338
1339 static void ds1307_clks_register(struct ds1307 *ds1307)
1340 {
1341 int ret;
1342
1343 if (ds1307->type != ds_3231)
1344 return;
1345
1346 ret = ds3231_clks_register(ds1307);
1347 if (ret) {
1348 dev_warn(&ds1307->client->dev,
1349 "unable to register clock device %d\n", ret);
1350 }
1351 }
1352
1353 #else
1354
1355 static void ds1307_clks_register(struct ds1307 *ds1307)
1356 {
1357 }
1358
1359 #endif /* CONFIG_COMMON_CLK */
1360
1361 static int ds1307_probe(struct i2c_client *client,
1362 const struct i2c_device_id *id)
1363 {
1364 struct ds1307 *ds1307;
1365 int err = -ENODEV;
1366 int tmp, wday;
1367 struct chip_desc *chip;
1368 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
1369 bool want_irq = false;
1370 bool ds1307_can_wakeup_device = false;
1371 unsigned char *buf;
1372 struct ds1307_platform_data *pdata = dev_get_platdata(&client->dev);
1373 struct rtc_time tm;
1374 unsigned long timestamp;
1375
1376 irq_handler_t irq_handler = ds1307_irq;
1377
1378 static const int bbsqi_bitpos[] = {
1379 [ds_1337] = 0,
1380 [ds_1339] = DS1339_BIT_BBSQI,
1381 [ds_3231] = DS3231_BIT_BBSQW,
1382 };
1383 const struct rtc_class_ops *rtc_ops = &ds13xx_rtc_ops;
1384
1385 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)
1386 && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK))
1387 return -EIO;
1388
1389 ds1307 = devm_kzalloc(&client->dev, sizeof(struct ds1307), GFP_KERNEL);
1390 if (!ds1307)
1391 return -ENOMEM;
1392
1393 i2c_set_clientdata(client, ds1307);
1394
1395 ds1307->client = client;
1396
1397 if (client->dev.of_node) {
1398 ds1307->type = (enum ds_type)
1399 of_device_get_match_data(&client->dev);
1400 chip = &chips[ds1307->type];
1401 } else if (id) {
1402 chip = &chips[id->driver_data];
1403 ds1307->type = id->driver_data;
1404 } else {
1405 const struct acpi_device_id *acpi_id;
1406
1407 acpi_id = acpi_match_device(ACPI_PTR(ds1307_acpi_ids),
1408 &client->dev);
1409 if (!acpi_id)
1410 return -ENODEV;
1411 chip = &chips[acpi_id->driver_data];
1412 ds1307->type = acpi_id->driver_data;
1413 }
1414
1415 if (!pdata)
1416 ds1307_trickle_init(client, chip);
1417 else if (pdata->trickle_charger_setup)
1418 chip->trickle_charger_setup = pdata->trickle_charger_setup;
1419
1420 if (chip->trickle_charger_setup && chip->trickle_charger_reg) {
1421 dev_dbg(&client->dev, "writing trickle charger info 0x%x to 0x%x\n",
1422 DS13XX_TRICKLE_CHARGER_MAGIC | chip->trickle_charger_setup,
1423 chip->trickle_charger_reg);
1424 i2c_smbus_write_byte_data(client, chip->trickle_charger_reg,
1425 DS13XX_TRICKLE_CHARGER_MAGIC |
1426 chip->trickle_charger_setup);
1427 }
1428
1429 buf = ds1307->regs;
1430 if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
1431 ds1307->read_block_data = ds1307_native_smbus_read_block_data;
1432 ds1307->write_block_data = ds1307_native_smbus_write_block_data;
1433 } else {
1434 ds1307->read_block_data = ds1307_read_block_data;
1435 ds1307->write_block_data = ds1307_write_block_data;
1436 }
1437
1438 #ifdef CONFIG_OF
1439 /*
1440 * For devices with no IRQ directly connected to the SoC, the RTC chip
1441 * can be forced as a wakeup source by stating that explicitly in
1442 * the device's .dts file using the "wakeup-source" boolean property.
1443 * If the "wakeup-source" property is set, don't request an IRQ.
1444 * This will guarantee the 'wakealarm' sysfs entry is available on the device,
1445 * if supported by the RTC.
1446 */
1447 if (of_property_read_bool(client->dev.of_node, "wakeup-source")) {
1448 ds1307_can_wakeup_device = true;
1449 }
1450 /* Intersil ISL12057 DT backward compatibility */
1451 if (of_property_read_bool(client->dev.of_node,
1452 "isil,irq2-can-wakeup-machine")) {
1453 ds1307_can_wakeup_device = true;
1454 }
1455 #endif
1456
1457 switch (ds1307->type) {
1458 case ds_1337:
1459 case ds_1339:
1460 case ds_3231:
1461 /* get registers that the "rtc" read below won't read... */
1462 tmp = ds1307->read_block_data(ds1307->client,
1463 DS1337_REG_CONTROL, 2, buf);
1464 if (tmp != 2) {
1465 dev_dbg(&client->dev, "read error %d\n", tmp);
1466 err = -EIO;
1467 goto exit;
1468 }
1469
1470 /* oscillator off? turn it on, so clock can tick. */
1471 if (ds1307->regs[0] & DS1337_BIT_nEOSC)
1472 ds1307->regs[0] &= ~DS1337_BIT_nEOSC;
1473
1474 /*
1475 * Using IRQ or defined as wakeup-source?
1476 * Disable the square wave and both alarms.
1477 * For some variants, be sure alarms can trigger when we're
1478 * running on Vbackup (BBSQI/BBSQW)
1479 */
1480 if (chip->alarm && (ds1307->client->irq > 0 ||
1481 ds1307_can_wakeup_device)) {
1482 ds1307->regs[0] |= DS1337_BIT_INTCN
1483 | bbsqi_bitpos[ds1307->type];
1484 ds1307->regs[0] &= ~(DS1337_BIT_A2IE | DS1337_BIT_A1IE);
1485
1486 want_irq = true;
1487 }
1488
1489 i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL,
1490 ds1307->regs[0]);
1491
1492 /* oscillator fault? clear flag, and warn */
1493 if (ds1307->regs[1] & DS1337_BIT_OSF) {
1494 i2c_smbus_write_byte_data(client, DS1337_REG_STATUS,
1495 ds1307->regs[1] & ~DS1337_BIT_OSF);
1496 dev_warn(&client->dev, "SET TIME!\n");
1497 }
1498 break;
1499
1500 case rx_8025:
1501 tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
1502 RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
1503 if (tmp != 2) {
1504 dev_dbg(&client->dev, "read error %d\n", tmp);
1505 err = -EIO;
1506 goto exit;
1507 }
1508
1509 /* oscillator off? turn it on, so clock can tick. */
1510 if (!(ds1307->regs[1] & RX8025_BIT_XST)) {
1511 ds1307->regs[1] |= RX8025_BIT_XST;
1512 i2c_smbus_write_byte_data(client,
1513 RX8025_REG_CTRL2 << 4 | 0x08,
1514 ds1307->regs[1]);
1515 dev_warn(&client->dev,
1516 "oscillator stop detected - SET TIME!\n");
1517 }
1518
1519 if (ds1307->regs[1] & RX8025_BIT_PON) {
1520 ds1307->regs[1] &= ~RX8025_BIT_PON;
1521 i2c_smbus_write_byte_data(client,
1522 RX8025_REG_CTRL2 << 4 | 0x08,
1523 ds1307->regs[1]);
1524 dev_warn(&client->dev, "power-on detected\n");
1525 }
1526
1527 if (ds1307->regs[1] & RX8025_BIT_VDET) {
1528 ds1307->regs[1] &= ~RX8025_BIT_VDET;
1529 i2c_smbus_write_byte_data(client,
1530 RX8025_REG_CTRL2 << 4 | 0x08,
1531 ds1307->regs[1]);
1532 dev_warn(&client->dev, "voltage drop detected\n");
1533 }
1534
1535 /* make sure we are running in 24hour mode */
1536 if (!(ds1307->regs[0] & RX8025_BIT_2412)) {
1537 u8 hour;
1538
1539 /* switch to 24 hour mode */
1540 i2c_smbus_write_byte_data(client,
1541 RX8025_REG_CTRL1 << 4 | 0x08,
1542 ds1307->regs[0] |
1543 RX8025_BIT_2412);
1544
1545 tmp = i2c_smbus_read_i2c_block_data(ds1307->client,
1546 RX8025_REG_CTRL1 << 4 | 0x08, 2, buf);
1547 if (tmp != 2) {
1548 dev_dbg(&client->dev, "read error %d\n", tmp);
1549 err = -EIO;
1550 goto exit;
1551 }
1552
1553 /* correct hour */
1554 hour = bcd2bin(ds1307->regs[DS1307_REG_HOUR]);
1555 if (hour == 12)
1556 hour = 0;
1557 if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1558 hour += 12;
1559
1560 i2c_smbus_write_byte_data(client,
1561 DS1307_REG_HOUR << 4 | 0x08,
1562 hour);
1563 }
1564 break;
1565 case ds_1388:
1566 ds1307->offset = 1; /* Seconds starts at 1 */
1567 break;
1568 case mcp794xx:
1569 rtc_ops = &mcp794xx_rtc_ops;
1570 if (ds1307->client->irq > 0 && chip->alarm) {
1571 irq_handler = mcp794xx_irq;
1572 want_irq = true;
1573 }
1574 break;
1575 default:
1576 break;
1577 }
1578
1579 read_rtc:
1580 /* read RTC registers */
1581 tmp = ds1307->read_block_data(ds1307->client, ds1307->offset, 8, buf);
1582 if (tmp != 8) {
1583 dev_dbg(&client->dev, "read error %d\n", tmp);
1584 err = -EIO;
1585 goto exit;
1586 }
1587
1588 /*
1589 * minimal sanity checking; some chips (like DS1340) don't
1590 * specify the extra bits as must-be-zero, but there are
1591 * still a few values that are clearly out-of-range.
1592 */
1593 tmp = ds1307->regs[DS1307_REG_SECS];
1594 switch (ds1307->type) {
1595 case ds_1307:
1596 case m41t0:
1597 case m41t00:
1598 /* clock halted? turn it on, so clock can tick. */
1599 if (tmp & DS1307_BIT_CH) {
1600 i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1601 dev_warn(&client->dev, "SET TIME!\n");
1602 goto read_rtc;
1603 }
1604 break;
1605 case ds_1338:
1606 /* clock halted? turn it on, so clock can tick. */
1607 if (tmp & DS1307_BIT_CH)
1608 i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1609
1610 /* oscillator fault? clear flag, and warn */
1611 if (ds1307->regs[DS1307_REG_CONTROL] & DS1338_BIT_OSF) {
1612 i2c_smbus_write_byte_data(client, DS1307_REG_CONTROL,
1613 ds1307->regs[DS1307_REG_CONTROL]
1614 & ~DS1338_BIT_OSF);
1615 dev_warn(&client->dev, "SET TIME!\n");
1616 goto read_rtc;
1617 }
1618 break;
1619 case ds_1340:
1620 /* clock halted? turn it on, so clock can tick. */
1621 if (tmp & DS1340_BIT_nEOSC)
1622 i2c_smbus_write_byte_data(client, DS1307_REG_SECS, 0);
1623
1624 tmp = i2c_smbus_read_byte_data(client, DS1340_REG_FLAG);
1625 if (tmp < 0) {
1626 dev_dbg(&client->dev, "read error %d\n", tmp);
1627 err = -EIO;
1628 goto exit;
1629 }
1630
1631 /* oscillator fault? clear flag, and warn */
1632 if (tmp & DS1340_BIT_OSF) {
1633 i2c_smbus_write_byte_data(client, DS1340_REG_FLAG, 0);
1634 dev_warn(&client->dev, "SET TIME!\n");
1635 }
1636 break;
1637 case mcp794xx:
1638 /* make sure that the backup battery is enabled */
1639 if (!(ds1307->regs[DS1307_REG_WDAY] & MCP794XX_BIT_VBATEN)) {
1640 i2c_smbus_write_byte_data(client, DS1307_REG_WDAY,
1641 ds1307->regs[DS1307_REG_WDAY]
1642 | MCP794XX_BIT_VBATEN);
1643 }
1644
1645 /* clock halted? turn it on, so clock can tick. */
1646 if (!(tmp & MCP794XX_BIT_ST)) {
1647 i2c_smbus_write_byte_data(client, DS1307_REG_SECS,
1648 MCP794XX_BIT_ST);
1649 dev_warn(&client->dev, "SET TIME!\n");
1650 goto read_rtc;
1651 }
1652
1653 break;
1654 default:
1655 break;
1656 }
1657
1658 tmp = ds1307->regs[DS1307_REG_HOUR];
1659 switch (ds1307->type) {
1660 case ds_1340:
1661 case m41t0:
1662 case m41t00:
1663 /*
1664 * NOTE: ignores century bits; fix before deploying
1665 * systems that will run through year 2100.
1666 */
1667 break;
1668 case rx_8025:
1669 break;
1670 default:
1671 if (!(tmp & DS1307_BIT_12HR))
1672 break;
1673
1674 /*
1675 * Be sure we're in 24 hour mode. Multi-master systems
1676 * take note...
1677 */
1678 tmp = bcd2bin(tmp & 0x1f);
1679 if (tmp == 12)
1680 tmp = 0;
1681 if (ds1307->regs[DS1307_REG_HOUR] & DS1307_BIT_PM)
1682 tmp += 12;
1683 i2c_smbus_write_byte_data(client,
1684 ds1307->offset + DS1307_REG_HOUR,
1685 bin2bcd(tmp));
1686 }
1687
1688 /*
1689 * Some IPs have weekday reset value = 0x1 which might not correct
1690 * hence compute the wday using the current date/month/year values
1691 */
1692 ds1307_get_time(&client->dev, &tm);
1693 wday = tm.tm_wday;
1694 timestamp = rtc_tm_to_time64(&tm);
1695 rtc_time64_to_tm(timestamp, &tm);
1696
1697 /*
1698 * Check if reset wday is different from the computed wday
1699 * If different then set the wday which we computed using
1700 * timestamp
1701 */
1702 if (wday != tm.tm_wday) {
1703 wday = i2c_smbus_read_byte_data(client, MCP794XX_REG_WEEKDAY);
1704 wday = wday & ~MCP794XX_REG_WEEKDAY_WDAY_MASK;
1705 wday = wday | (tm.tm_wday + 1);
1706 i2c_smbus_write_byte_data(client, MCP794XX_REG_WEEKDAY, wday);
1707 }
1708
1709 if (want_irq) {
1710 device_set_wakeup_capable(&client->dev, true);
1711 set_bit(HAS_ALARM, &ds1307->flags);
1712 }
1713 ds1307->rtc = devm_rtc_device_register(&client->dev, client->name,
1714 rtc_ops, THIS_MODULE);
1715 if (IS_ERR(ds1307->rtc)) {
1716 return PTR_ERR(ds1307->rtc);
1717 }
1718
1719 if (ds1307_can_wakeup_device && ds1307->client->irq <= 0) {
1720 /* Disable request for an IRQ */
1721 want_irq = false;
1722 dev_info(&client->dev, "'wakeup-source' is set, request for an IRQ is disabled!\n");
1723 /* We cannot support UIE mode if we do not have an IRQ line */
1724 ds1307->rtc->uie_unsupported = 1;
1725 }
1726
1727 if (want_irq) {
1728 err = devm_request_threaded_irq(&client->dev,
1729 client->irq, NULL, irq_handler,
1730 IRQF_SHARED | IRQF_ONESHOT,
1731 ds1307->rtc->name, client);
1732 if (err) {
1733 client->irq = 0;
1734 device_set_wakeup_capable(&client->dev, false);
1735 clear_bit(HAS_ALARM, &ds1307->flags);
1736 dev_err(&client->dev, "unable to request IRQ!\n");
1737 } else
1738 dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
1739 }
1740
1741 if (chip->nvram_size) {
1742
1743 ds1307->nvram = devm_kzalloc(&client->dev,
1744 sizeof(struct bin_attribute),
1745 GFP_KERNEL);
1746 if (!ds1307->nvram) {
1747 dev_err(&client->dev, "cannot allocate memory for nvram sysfs\n");
1748 } else {
1749
1750 ds1307->nvram->attr.name = "nvram";
1751 ds1307->nvram->attr.mode = S_IRUGO | S_IWUSR;
1752
1753 sysfs_bin_attr_init(ds1307->nvram);
1754
1755 ds1307->nvram->read = ds1307_nvram_read;
1756 ds1307->nvram->write = ds1307_nvram_write;
1757 ds1307->nvram->size = chip->nvram_size;
1758 ds1307->nvram_offset = chip->nvram_offset;
1759
1760 err = sysfs_create_bin_file(&client->dev.kobj,
1761 ds1307->nvram);
1762 if (err) {
1763 dev_err(&client->dev,
1764 "unable to create sysfs file: %s\n",
1765 ds1307->nvram->attr.name);
1766 } else {
1767 set_bit(HAS_NVRAM, &ds1307->flags);
1768 dev_info(&client->dev, "%zu bytes nvram\n",
1769 ds1307->nvram->size);
1770 }
1771 }
1772 }
1773
1774 ds1307_hwmon_register(ds1307);
1775 ds1307_clks_register(ds1307);
1776
1777 return 0;
1778
1779 exit:
1780 return err;
1781 }
1782
1783 static int ds1307_remove(struct i2c_client *client)
1784 {
1785 struct ds1307 *ds1307 = i2c_get_clientdata(client);
1786
1787 if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
1788 sysfs_remove_bin_file(&client->dev.kobj, ds1307->nvram);
1789
1790 return 0;
1791 }
1792
1793 static struct i2c_driver ds1307_driver = {
1794 .driver = {
1795 .name = "rtc-ds1307",
1796 .of_match_table = of_match_ptr(ds1307_of_match),
1797 .acpi_match_table = ACPI_PTR(ds1307_acpi_ids),
1798 },
1799 .probe = ds1307_probe,
1800 .remove = ds1307_remove,
1801 .id_table = ds1307_id,
1802 };
1803
1804 module_i2c_driver(ds1307_driver);
1805
1806 MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1807 MODULE_LICENSE("GPL");
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