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/bcd.h>
15 #include <linux/i2c.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/of_irq.h>
20 #include <linux/pm_wakeirq.h>
21 #include <linux/rtc/ds1307.h>
22 #include <linux/rtc.h>
23 #include <linux/slab.h>
24 #include <linux/string.h>
27 * We can't determine type by probing, but if we expect pre-Linux code
28 * to have set the chip up as a clock (turning on the oscillator and
29 * setting the date and time), Linux can ignore the non-clock features.
30 * That's a natural job for a factory or repair bench.
43 last_ds_type
/* always last */
44 /* rs5c372 too? different address... */
48 /* RTC registers don't differ much, except for the century flag */
49 #define DS1307_REG_SECS 0x00 /* 00-59 */
50 # define DS1307_BIT_CH 0x80
51 # define DS1340_BIT_nEOSC 0x80
52 # define MCP794XX_BIT_ST 0x80
53 #define DS1307_REG_MIN 0x01 /* 00-59 */
54 #define DS1307_REG_HOUR 0x02 /* 00-23, or 1-12{am,pm} */
55 # define DS1307_BIT_12HR 0x40 /* in REG_HOUR */
56 # define DS1307_BIT_PM 0x20 /* in REG_HOUR */
57 # define DS1340_BIT_CENTURY_EN 0x80 /* in REG_HOUR */
58 # define DS1340_BIT_CENTURY 0x40 /* in REG_HOUR */
59 #define DS1307_REG_WDAY 0x03 /* 01-07 */
60 # define MCP794XX_BIT_VBATEN 0x08
61 #define DS1307_REG_MDAY 0x04 /* 01-31 */
62 #define DS1307_REG_MONTH 0x05 /* 01-12 */
63 # define DS1337_BIT_CENTURY 0x80 /* in REG_MONTH */
64 #define DS1307_REG_YEAR 0x06 /* 00-99 */
67 * Other registers (control, status, alarms, trickle charge, NVRAM, etc)
68 * start at 7, and they differ a LOT. Only control and status matter for
69 * basic RTC date and time functionality; be careful using them.
71 #define DS1307_REG_CONTROL 0x07 /* or ds1338 */
72 # define DS1307_BIT_OUT 0x80
73 # define DS1338_BIT_OSF 0x20
74 # define DS1307_BIT_SQWE 0x10
75 # define DS1307_BIT_RS1 0x02
76 # define DS1307_BIT_RS0 0x01
77 #define DS1337_REG_CONTROL 0x0e
78 # define DS1337_BIT_nEOSC 0x80
79 # define DS1339_BIT_BBSQI 0x20
80 # define DS3231_BIT_BBSQW 0x40 /* same as BBSQI */
81 # define DS1337_BIT_RS2 0x10
82 # define DS1337_BIT_RS1 0x08
83 # define DS1337_BIT_INTCN 0x04
84 # define DS1337_BIT_A2IE 0x02
85 # define DS1337_BIT_A1IE 0x01
86 #define DS1340_REG_CONTROL 0x07
87 # define DS1340_BIT_OUT 0x80
88 # define DS1340_BIT_FT 0x40
89 # define DS1340_BIT_CALIB_SIGN 0x20
90 # define DS1340_M_CALIBRATION 0x1f
91 #define DS1340_REG_FLAG 0x09
92 # define DS1340_BIT_OSF 0x80
93 #define DS1337_REG_STATUS 0x0f
94 # define DS1337_BIT_OSF 0x80
95 # define DS1337_BIT_A2I 0x02
96 # define DS1337_BIT_A1I 0x01
97 #define DS1339_REG_ALARM1_SECS 0x07
99 #define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
101 #define RX8025_REG_CTRL1 0x0e
102 # define RX8025_BIT_2412 0x20
103 #define RX8025_REG_CTRL2 0x0f
104 # define RX8025_BIT_PON 0x10
105 # define RX8025_BIT_VDET 0x40
106 # define RX8025_BIT_XST 0x20
110 u8 offset
; /* register's offset */
113 struct bin_attribute
*nvram
;
116 #define HAS_NVRAM 0 /* bit 0 == sysfs file active */
117 #define HAS_ALARM 1 /* bit 1 == irq claimed */
118 struct i2c_client
*client
;
119 struct rtc_device
*rtc
;
121 s32 (*read_block_data
)(const struct i2c_client
*client
, u8 command
,
122 u8 length
, u8
*values
);
123 s32 (*write_block_data
)(const struct i2c_client
*client
, u8 command
,
124 u8 length
, const u8
*values
);
131 u16 trickle_charger_reg
;
132 u8 trickle_charger_setup
;
133 u8 (*do_trickle_setup
)(struct i2c_client
*, uint32_t, bool);
136 static u8
do_trickle_setup_ds1339(struct i2c_client
*,
137 uint32_t ohms
, bool diode
);
139 static struct chip_desc chips
[last_ds_type
] = {
153 .trickle_charger_reg
= 0x10,
154 .do_trickle_setup
= &do_trickle_setup_ds1339
,
157 .trickle_charger_reg
= 0x08,
160 .trickle_charger_reg
= 0x0a,
167 /* this is battery backed SRAM */
168 .nvram_offset
= 0x20,
173 static const struct i2c_device_id ds1307_id
[] = {
174 { "ds1307", ds_1307
},
175 { "ds1337", ds_1337
},
176 { "ds1338", ds_1338
},
177 { "ds1339", ds_1339
},
178 { "ds1388", ds_1388
},
179 { "ds1340", ds_1340
},
180 { "ds3231", ds_3231
},
181 { "m41t00", m41t00
},
182 { "mcp7940x", mcp794xx
},
183 { "mcp7941x", mcp794xx
},
184 { "pt7c4338", ds_1307
},
185 { "rx8025", rx_8025
},
188 MODULE_DEVICE_TABLE(i2c
, ds1307_id
);
190 /*----------------------------------------------------------------------*/
192 #define BLOCK_DATA_MAX_TRIES 10
194 static s32
ds1307_read_block_data_once(const struct i2c_client
*client
,
195 u8 command
, u8 length
, u8
*values
)
199 for (i
= 0; i
< length
; i
++) {
200 data
= i2c_smbus_read_byte_data(client
, command
+ i
);
208 static s32
ds1307_read_block_data(const struct i2c_client
*client
, u8 command
,
209 u8 length
, u8
*values
)
215 dev_dbg(&client
->dev
, "ds1307_read_block_data (length=%d)\n", length
);
216 ret
= ds1307_read_block_data_once(client
, command
, length
, values
);
220 if (++tries
> BLOCK_DATA_MAX_TRIES
) {
221 dev_err(&client
->dev
,
222 "ds1307_read_block_data failed\n");
225 memcpy(oldvalues
, values
, length
);
226 ret
= ds1307_read_block_data_once(client
, command
, length
,
230 } while (memcmp(oldvalues
, values
, length
));
234 static s32
ds1307_write_block_data(const struct i2c_client
*client
, u8 command
,
235 u8 length
, const u8
*values
)
240 dev_dbg(&client
->dev
, "ds1307_write_block_data (length=%d)\n", length
);
244 if (++tries
> BLOCK_DATA_MAX_TRIES
) {
245 dev_err(&client
->dev
,
246 "ds1307_write_block_data failed\n");
249 for (i
= 0; i
< length
; i
++) {
250 ret
= i2c_smbus_write_byte_data(client
, command
+ i
,
255 ret
= ds1307_read_block_data_once(client
, command
, length
,
259 } while (memcmp(currvalues
, values
, length
));
263 /*----------------------------------------------------------------------*/
265 /* These RTC devices are not designed to be connected to a SMbus adapter.
266 SMbus limits block operations length to 32 bytes, whereas it's not
267 limited on I2C buses. As a result, accesses may exceed 32 bytes;
268 in that case, split them into smaller blocks */
270 static s32
ds1307_native_smbus_write_block_data(const struct i2c_client
*client
,
271 u8 command
, u8 length
, const u8
*values
)
275 if (length
<= I2C_SMBUS_BLOCK_MAX
)
276 return i2c_smbus_write_i2c_block_data(client
,
277 command
, length
, values
);
279 while (suboffset
< length
) {
280 s32 retval
= i2c_smbus_write_i2c_block_data(client
,
282 min(I2C_SMBUS_BLOCK_MAX
, length
- suboffset
),
287 suboffset
+= I2C_SMBUS_BLOCK_MAX
;
292 static s32
ds1307_native_smbus_read_block_data(const struct i2c_client
*client
,
293 u8 command
, u8 length
, u8
*values
)
297 if (length
<= I2C_SMBUS_BLOCK_MAX
)
298 return i2c_smbus_read_i2c_block_data(client
,
299 command
, length
, values
);
301 while (suboffset
< length
) {
302 s32 retval
= i2c_smbus_read_i2c_block_data(client
,
304 min(I2C_SMBUS_BLOCK_MAX
, length
- suboffset
),
309 suboffset
+= I2C_SMBUS_BLOCK_MAX
;
314 /*----------------------------------------------------------------------*/
317 * The ds1337 and ds1339 both have two alarms, but we only use the first
318 * one (with a "seconds" field). For ds1337 we expect nINTA is our alarm
319 * signal; ds1339 chips have only one alarm signal.
321 static irqreturn_t
ds1307_irq(int irq
, void *dev_id
)
323 struct i2c_client
*client
= dev_id
;
324 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
325 struct mutex
*lock
= &ds1307
->rtc
->ops_lock
;
329 stat
= i2c_smbus_read_byte_data(client
, DS1337_REG_STATUS
);
333 if (stat
& DS1337_BIT_A1I
) {
334 stat
&= ~DS1337_BIT_A1I
;
335 i2c_smbus_write_byte_data(client
, DS1337_REG_STATUS
, stat
);
337 control
= i2c_smbus_read_byte_data(client
, DS1337_REG_CONTROL
);
341 control
&= ~DS1337_BIT_A1IE
;
342 i2c_smbus_write_byte_data(client
, DS1337_REG_CONTROL
, control
);
344 rtc_update_irq(ds1307
->rtc
, 1, RTC_AF
| RTC_IRQF
);
353 /*----------------------------------------------------------------------*/
355 static int ds1307_get_time(struct device
*dev
, struct rtc_time
*t
)
357 struct ds1307
*ds1307
= dev_get_drvdata(dev
);
360 /* read the RTC date and time registers all at once */
361 tmp
= ds1307
->read_block_data(ds1307
->client
,
362 ds1307
->offset
, 7, ds1307
->regs
);
364 dev_err(dev
, "%s error %d\n", "read", tmp
);
368 dev_dbg(dev
, "%s: %7ph\n", "read", ds1307
->regs
);
370 t
->tm_sec
= bcd2bin(ds1307
->regs
[DS1307_REG_SECS
] & 0x7f);
371 t
->tm_min
= bcd2bin(ds1307
->regs
[DS1307_REG_MIN
] & 0x7f);
372 tmp
= ds1307
->regs
[DS1307_REG_HOUR
] & 0x3f;
373 t
->tm_hour
= bcd2bin(tmp
);
374 t
->tm_wday
= bcd2bin(ds1307
->regs
[DS1307_REG_WDAY
] & 0x07) - 1;
375 t
->tm_mday
= bcd2bin(ds1307
->regs
[DS1307_REG_MDAY
] & 0x3f);
376 tmp
= ds1307
->regs
[DS1307_REG_MONTH
] & 0x1f;
377 t
->tm_mon
= bcd2bin(tmp
) - 1;
379 /* assume 20YY not 19YY, and ignore DS1337_BIT_CENTURY */
380 t
->tm_year
= bcd2bin(ds1307
->regs
[DS1307_REG_YEAR
]) + 100;
382 dev_dbg(dev
, "%s secs=%d, mins=%d, "
383 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
384 "read", t
->tm_sec
, t
->tm_min
,
385 t
->tm_hour
, t
->tm_mday
,
386 t
->tm_mon
, t
->tm_year
, t
->tm_wday
);
388 /* initial clock setting can be undefined */
389 return rtc_valid_tm(t
);
392 static int ds1307_set_time(struct device
*dev
, struct rtc_time
*t
)
394 struct ds1307
*ds1307
= dev_get_drvdata(dev
);
397 u8
*buf
= ds1307
->regs
;
399 dev_dbg(dev
, "%s secs=%d, mins=%d, "
400 "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
401 "write", t
->tm_sec
, t
->tm_min
,
402 t
->tm_hour
, t
->tm_mday
,
403 t
->tm_mon
, t
->tm_year
, t
->tm_wday
);
405 buf
[DS1307_REG_SECS
] = bin2bcd(t
->tm_sec
);
406 buf
[DS1307_REG_MIN
] = bin2bcd(t
->tm_min
);
407 buf
[DS1307_REG_HOUR
] = bin2bcd(t
->tm_hour
);
408 buf
[DS1307_REG_WDAY
] = bin2bcd(t
->tm_wday
+ 1);
409 buf
[DS1307_REG_MDAY
] = bin2bcd(t
->tm_mday
);
410 buf
[DS1307_REG_MONTH
] = bin2bcd(t
->tm_mon
+ 1);
412 /* assume 20YY not 19YY */
413 tmp
= t
->tm_year
- 100;
414 buf
[DS1307_REG_YEAR
] = bin2bcd(tmp
);
416 switch (ds1307
->type
) {
420 buf
[DS1307_REG_MONTH
] |= DS1337_BIT_CENTURY
;
423 buf
[DS1307_REG_HOUR
] |= DS1340_BIT_CENTURY_EN
424 | DS1340_BIT_CENTURY
;
428 * these bits were cleared when preparing the date/time
429 * values and need to be set again before writing the
430 * buffer out to the device.
432 buf
[DS1307_REG_SECS
] |= MCP794XX_BIT_ST
;
433 buf
[DS1307_REG_WDAY
] |= MCP794XX_BIT_VBATEN
;
439 dev_dbg(dev
, "%s: %7ph\n", "write", buf
);
441 result
= ds1307
->write_block_data(ds1307
->client
,
442 ds1307
->offset
, 7, buf
);
444 dev_err(dev
, "%s error %d\n", "write", result
);
450 static int ds1337_read_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
452 struct i2c_client
*client
= to_i2c_client(dev
);
453 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
456 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
459 /* read all ALARM1, ALARM2, and status registers at once */
460 ret
= ds1307
->read_block_data(client
,
461 DS1339_REG_ALARM1_SECS
, 9, ds1307
->regs
);
463 dev_err(dev
, "%s error %d\n", "alarm read", ret
);
467 dev_dbg(dev
, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
469 ds1307
->regs
[0], ds1307
->regs
[1],
470 ds1307
->regs
[2], ds1307
->regs
[3],
471 ds1307
->regs
[4], ds1307
->regs
[5],
472 ds1307
->regs
[6], ds1307
->regs
[7],
476 * report alarm time (ALARM1); assume 24 hour and day-of-month modes,
477 * and that all four fields are checked matches
479 t
->time
.tm_sec
= bcd2bin(ds1307
->regs
[0] & 0x7f);
480 t
->time
.tm_min
= bcd2bin(ds1307
->regs
[1] & 0x7f);
481 t
->time
.tm_hour
= bcd2bin(ds1307
->regs
[2] & 0x3f);
482 t
->time
.tm_mday
= bcd2bin(ds1307
->regs
[3] & 0x3f);
484 t
->time
.tm_year
= -1;
485 t
->time
.tm_wday
= -1;
486 t
->time
.tm_yday
= -1;
487 t
->time
.tm_isdst
= -1;
490 t
->enabled
= !!(ds1307
->regs
[7] & DS1337_BIT_A1IE
);
491 t
->pending
= !!(ds1307
->regs
[8] & DS1337_BIT_A1I
);
493 dev_dbg(dev
, "%s secs=%d, mins=%d, "
494 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
495 "alarm read", t
->time
.tm_sec
, t
->time
.tm_min
,
496 t
->time
.tm_hour
, t
->time
.tm_mday
,
497 t
->enabled
, t
->pending
);
502 static int ds1337_set_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
504 struct i2c_client
*client
= to_i2c_client(dev
);
505 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
506 unsigned char *buf
= ds1307
->regs
;
510 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
513 dev_dbg(dev
, "%s secs=%d, mins=%d, "
514 "hours=%d, mday=%d, enabled=%d, pending=%d\n",
515 "alarm set", t
->time
.tm_sec
, t
->time
.tm_min
,
516 t
->time
.tm_hour
, t
->time
.tm_mday
,
517 t
->enabled
, t
->pending
);
519 /* read current status of both alarms and the chip */
520 ret
= ds1307
->read_block_data(client
,
521 DS1339_REG_ALARM1_SECS
, 9, buf
);
523 dev_err(dev
, "%s error %d\n", "alarm write", ret
);
526 control
= ds1307
->regs
[7];
527 status
= ds1307
->regs
[8];
529 dev_dbg(dev
, "%s: %02x %02x %02x %02x, %02x %02x %02x, %02x %02x\n",
530 "alarm set (old status)",
531 ds1307
->regs
[0], ds1307
->regs
[1],
532 ds1307
->regs
[2], ds1307
->regs
[3],
533 ds1307
->regs
[4], ds1307
->regs
[5],
534 ds1307
->regs
[6], control
, status
);
536 /* set ALARM1, using 24 hour and day-of-month modes */
537 buf
[0] = bin2bcd(t
->time
.tm_sec
);
538 buf
[1] = bin2bcd(t
->time
.tm_min
);
539 buf
[2] = bin2bcd(t
->time
.tm_hour
);
540 buf
[3] = bin2bcd(t
->time
.tm_mday
);
542 /* set ALARM2 to non-garbage */
547 /* optionally enable ALARM1 */
548 buf
[7] = control
& ~(DS1337_BIT_A1IE
| DS1337_BIT_A2IE
);
550 dev_dbg(dev
, "alarm IRQ armed\n");
551 buf
[7] |= DS1337_BIT_A1IE
; /* only ALARM1 is used */
553 buf
[8] = status
& ~(DS1337_BIT_A1I
| DS1337_BIT_A2I
);
555 ret
= ds1307
->write_block_data(client
,
556 DS1339_REG_ALARM1_SECS
, 9, buf
);
558 dev_err(dev
, "can't set alarm time\n");
565 static int ds1307_alarm_irq_enable(struct device
*dev
, unsigned int enabled
)
567 struct i2c_client
*client
= to_i2c_client(dev
);
568 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
571 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
574 ret
= i2c_smbus_read_byte_data(client
, DS1337_REG_CONTROL
);
579 ret
|= DS1337_BIT_A1IE
;
581 ret
&= ~DS1337_BIT_A1IE
;
583 ret
= i2c_smbus_write_byte_data(client
, DS1337_REG_CONTROL
, ret
);
590 static const struct rtc_class_ops ds13xx_rtc_ops
= {
591 .read_time
= ds1307_get_time
,
592 .set_time
= ds1307_set_time
,
593 .read_alarm
= ds1337_read_alarm
,
594 .set_alarm
= ds1337_set_alarm
,
595 .alarm_irq_enable
= ds1307_alarm_irq_enable
,
598 /*----------------------------------------------------------------------*/
601 * Alarm support for mcp794xx devices.
604 #define MCP794XX_REG_CONTROL 0x07
605 # define MCP794XX_BIT_ALM0_EN 0x10
606 # define MCP794XX_BIT_ALM1_EN 0x20
607 #define MCP794XX_REG_ALARM0_BASE 0x0a
608 #define MCP794XX_REG_ALARM0_CTRL 0x0d
609 #define MCP794XX_REG_ALARM1_BASE 0x11
610 #define MCP794XX_REG_ALARM1_CTRL 0x14
611 # define MCP794XX_BIT_ALMX_IF (1 << 3)
612 # define MCP794XX_BIT_ALMX_C0 (1 << 4)
613 # define MCP794XX_BIT_ALMX_C1 (1 << 5)
614 # define MCP794XX_BIT_ALMX_C2 (1 << 6)
615 # define MCP794XX_BIT_ALMX_POL (1 << 7)
616 # define MCP794XX_MSK_ALMX_MATCH (MCP794XX_BIT_ALMX_C0 | \
617 MCP794XX_BIT_ALMX_C1 | \
618 MCP794XX_BIT_ALMX_C2)
620 static irqreturn_t
mcp794xx_irq(int irq
, void *dev_id
)
622 struct i2c_client
*client
= dev_id
;
623 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
624 struct mutex
*lock
= &ds1307
->rtc
->ops_lock
;
629 /* Check and clear alarm 0 interrupt flag. */
630 reg
= i2c_smbus_read_byte_data(client
, MCP794XX_REG_ALARM0_CTRL
);
633 if (!(reg
& MCP794XX_BIT_ALMX_IF
))
635 reg
&= ~MCP794XX_BIT_ALMX_IF
;
636 ret
= i2c_smbus_write_byte_data(client
, MCP794XX_REG_ALARM0_CTRL
, reg
);
640 /* Disable alarm 0. */
641 reg
= i2c_smbus_read_byte_data(client
, MCP794XX_REG_CONTROL
);
644 reg
&= ~MCP794XX_BIT_ALM0_EN
;
645 ret
= i2c_smbus_write_byte_data(client
, MCP794XX_REG_CONTROL
, reg
);
649 rtc_update_irq(ds1307
->rtc
, 1, RTC_AF
| RTC_IRQF
);
657 static int mcp794xx_read_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
659 struct i2c_client
*client
= to_i2c_client(dev
);
660 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
661 u8
*regs
= ds1307
->regs
;
664 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
667 /* Read control and alarm 0 registers. */
668 ret
= ds1307
->read_block_data(client
, MCP794XX_REG_CONTROL
, 10, regs
);
672 t
->enabled
= !!(regs
[0] & MCP794XX_BIT_ALM0_EN
);
674 /* Report alarm 0 time assuming 24-hour and day-of-month modes. */
675 t
->time
.tm_sec
= bcd2bin(ds1307
->regs
[3] & 0x7f);
676 t
->time
.tm_min
= bcd2bin(ds1307
->regs
[4] & 0x7f);
677 t
->time
.tm_hour
= bcd2bin(ds1307
->regs
[5] & 0x3f);
678 t
->time
.tm_wday
= bcd2bin(ds1307
->regs
[6] & 0x7) - 1;
679 t
->time
.tm_mday
= bcd2bin(ds1307
->regs
[7] & 0x3f);
680 t
->time
.tm_mon
= bcd2bin(ds1307
->regs
[8] & 0x1f) - 1;
681 t
->time
.tm_year
= -1;
682 t
->time
.tm_yday
= -1;
683 t
->time
.tm_isdst
= -1;
685 dev_dbg(dev
, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
686 "enabled=%d polarity=%d irq=%d match=%d\n", __func__
,
687 t
->time
.tm_sec
, t
->time
.tm_min
, t
->time
.tm_hour
,
688 t
->time
.tm_wday
, t
->time
.tm_mday
, t
->time
.tm_mon
, t
->enabled
,
689 !!(ds1307
->regs
[6] & MCP794XX_BIT_ALMX_POL
),
690 !!(ds1307
->regs
[6] & MCP794XX_BIT_ALMX_IF
),
691 (ds1307
->regs
[6] & MCP794XX_MSK_ALMX_MATCH
) >> 4);
696 static int mcp794xx_set_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
698 struct i2c_client
*client
= to_i2c_client(dev
);
699 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
700 unsigned char *regs
= ds1307
->regs
;
703 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
706 dev_dbg(dev
, "%s, sec=%d min=%d hour=%d wday=%d mday=%d mon=%d "
707 "enabled=%d pending=%d\n", __func__
,
708 t
->time
.tm_sec
, t
->time
.tm_min
, t
->time
.tm_hour
,
709 t
->time
.tm_wday
, t
->time
.tm_mday
, t
->time
.tm_mon
,
710 t
->enabled
, t
->pending
);
712 /* Read control and alarm 0 registers. */
713 ret
= ds1307
->read_block_data(client
, MCP794XX_REG_CONTROL
, 10, regs
);
717 /* Set alarm 0, using 24-hour and day-of-month modes. */
718 regs
[3] = bin2bcd(t
->time
.tm_sec
);
719 regs
[4] = bin2bcd(t
->time
.tm_min
);
720 regs
[5] = bin2bcd(t
->time
.tm_hour
);
721 regs
[6] = bin2bcd(t
->time
.tm_wday
) + 1;
722 regs
[7] = bin2bcd(t
->time
.tm_mday
);
723 regs
[8] = bin2bcd(t
->time
.tm_mon
) + 1;
725 /* Clear the alarm 0 interrupt flag. */
726 regs
[6] &= ~MCP794XX_BIT_ALMX_IF
;
727 /* Set alarm match: second, minute, hour, day, date, month. */
728 regs
[6] |= MCP794XX_MSK_ALMX_MATCH
;
729 /* Disable interrupt. We will not enable until completely programmed */
730 regs
[0] &= ~MCP794XX_BIT_ALM0_EN
;
732 ret
= ds1307
->write_block_data(client
, MCP794XX_REG_CONTROL
, 10, regs
);
738 regs
[0] |= MCP794XX_BIT_ALM0_EN
;
739 return i2c_smbus_write_byte_data(client
, MCP794XX_REG_CONTROL
, regs
[0]);
742 static int mcp794xx_alarm_irq_enable(struct device
*dev
, unsigned int enabled
)
744 struct i2c_client
*client
= to_i2c_client(dev
);
745 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
748 if (!test_bit(HAS_ALARM
, &ds1307
->flags
))
751 reg
= i2c_smbus_read_byte_data(client
, MCP794XX_REG_CONTROL
);
756 reg
|= MCP794XX_BIT_ALM0_EN
;
758 reg
&= ~MCP794XX_BIT_ALM0_EN
;
760 return i2c_smbus_write_byte_data(client
, MCP794XX_REG_CONTROL
, reg
);
763 static const struct rtc_class_ops mcp794xx_rtc_ops
= {
764 .read_time
= ds1307_get_time
,
765 .set_time
= ds1307_set_time
,
766 .read_alarm
= mcp794xx_read_alarm
,
767 .set_alarm
= mcp794xx_set_alarm
,
768 .alarm_irq_enable
= mcp794xx_alarm_irq_enable
,
771 /*----------------------------------------------------------------------*/
774 ds1307_nvram_read(struct file
*filp
, struct kobject
*kobj
,
775 struct bin_attribute
*attr
,
776 char *buf
, loff_t off
, size_t count
)
778 struct i2c_client
*client
;
779 struct ds1307
*ds1307
;
782 client
= kobj_to_i2c_client(kobj
);
783 ds1307
= i2c_get_clientdata(client
);
785 result
= ds1307
->read_block_data(client
, ds1307
->nvram_offset
+ off
,
788 dev_err(&client
->dev
, "%s error %d\n", "nvram read", result
);
793 ds1307_nvram_write(struct file
*filp
, struct kobject
*kobj
,
794 struct bin_attribute
*attr
,
795 char *buf
, loff_t off
, size_t count
)
797 struct i2c_client
*client
;
798 struct ds1307
*ds1307
;
801 client
= kobj_to_i2c_client(kobj
);
802 ds1307
= i2c_get_clientdata(client
);
804 result
= ds1307
->write_block_data(client
, ds1307
->nvram_offset
+ off
,
807 dev_err(&client
->dev
, "%s error %d\n", "nvram write", result
);
814 /*----------------------------------------------------------------------*/
816 static u8
do_trickle_setup_ds1339(struct i2c_client
*client
,
817 uint32_t ohms
, bool diode
)
819 u8 setup
= (diode
) ? DS1307_TRICKLE_CHARGER_DIODE
:
820 DS1307_TRICKLE_CHARGER_NO_DIODE
;
824 setup
|= DS1307_TRICKLE_CHARGER_250_OHM
;
827 setup
|= DS1307_TRICKLE_CHARGER_2K_OHM
;
830 setup
|= DS1307_TRICKLE_CHARGER_4K_OHM
;
833 dev_warn(&client
->dev
,
834 "Unsupported ohm value %u in dt\n", ohms
);
840 static void ds1307_trickle_of_init(struct i2c_client
*client
,
841 struct chip_desc
*chip
)
846 if (!chip
->do_trickle_setup
)
848 if (of_property_read_u32(client
->dev
.of_node
, "trickle-resistor-ohms" , &ohms
))
850 if (of_property_read_bool(client
->dev
.of_node
, "trickle-diode-disable"))
852 chip
->trickle_charger_setup
= chip
->do_trickle_setup(client
,
858 static int ds1307_probe(struct i2c_client
*client
,
859 const struct i2c_device_id
*id
)
861 struct ds1307
*ds1307
;
864 struct chip_desc
*chip
= &chips
[id
->driver_data
];
865 struct i2c_adapter
*adapter
= to_i2c_adapter(client
->dev
.parent
);
866 bool want_irq
= false;
868 struct ds1307_platform_data
*pdata
= dev_get_platdata(&client
->dev
);
869 irq_handler_t irq_handler
= ds1307_irq
;
871 static const int bbsqi_bitpos
[] = {
873 [ds_1339
] = DS1339_BIT_BBSQI
,
874 [ds_3231
] = DS3231_BIT_BBSQW
,
876 const struct rtc_class_ops
*rtc_ops
= &ds13xx_rtc_ops
;
878 if (!i2c_check_functionality(adapter
, I2C_FUNC_SMBUS_BYTE_DATA
)
879 && !i2c_check_functionality(adapter
, I2C_FUNC_SMBUS_I2C_BLOCK
))
882 ds1307
= devm_kzalloc(&client
->dev
, sizeof(struct ds1307
), GFP_KERNEL
);
886 i2c_set_clientdata(client
, ds1307
);
888 ds1307
->client
= client
;
889 ds1307
->type
= id
->driver_data
;
891 if (!pdata
&& client
->dev
.of_node
)
892 ds1307_trickle_of_init(client
, chip
);
893 else if (pdata
&& pdata
->trickle_charger_setup
)
894 chip
->trickle_charger_setup
= pdata
->trickle_charger_setup
;
896 if (chip
->trickle_charger_setup
&& chip
->trickle_charger_reg
) {
897 dev_dbg(&client
->dev
, "writing trickle charger info 0x%x to 0x%x\n",
898 DS13XX_TRICKLE_CHARGER_MAGIC
| chip
->trickle_charger_setup
,
899 chip
->trickle_charger_reg
);
900 i2c_smbus_write_byte_data(client
, chip
->trickle_charger_reg
,
901 DS13XX_TRICKLE_CHARGER_MAGIC
|
902 chip
->trickle_charger_setup
);
906 if (i2c_check_functionality(adapter
, I2C_FUNC_SMBUS_I2C_BLOCK
)) {
907 ds1307
->read_block_data
= ds1307_native_smbus_read_block_data
;
908 ds1307
->write_block_data
= ds1307_native_smbus_write_block_data
;
910 ds1307
->read_block_data
= ds1307_read_block_data
;
911 ds1307
->write_block_data
= ds1307_write_block_data
;
914 switch (ds1307
->type
) {
918 /* get registers that the "rtc" read below won't read... */
919 tmp
= ds1307
->read_block_data(ds1307
->client
,
920 DS1337_REG_CONTROL
, 2, buf
);
922 dev_dbg(&client
->dev
, "read error %d\n", tmp
);
927 /* oscillator off? turn it on, so clock can tick. */
928 if (ds1307
->regs
[0] & DS1337_BIT_nEOSC
)
929 ds1307
->regs
[0] &= ~DS1337_BIT_nEOSC
;
932 * Using IRQ? Disable the square wave and both alarms.
933 * For some variants, be sure alarms can trigger when we're
934 * running on Vbackup (BBSQI/BBSQW)
936 if (ds1307
->client
->irq
> 0 && chip
->alarm
) {
937 ds1307
->regs
[0] |= DS1337_BIT_INTCN
938 | bbsqi_bitpos
[ds1307
->type
];
939 ds1307
->regs
[0] &= ~(DS1337_BIT_A2IE
| DS1337_BIT_A1IE
);
944 i2c_smbus_write_byte_data(client
, DS1337_REG_CONTROL
,
947 /* oscillator fault? clear flag, and warn */
948 if (ds1307
->regs
[1] & DS1337_BIT_OSF
) {
949 i2c_smbus_write_byte_data(client
, DS1337_REG_STATUS
,
950 ds1307
->regs
[1] & ~DS1337_BIT_OSF
);
951 dev_warn(&client
->dev
, "SET TIME!\n");
956 tmp
= i2c_smbus_read_i2c_block_data(ds1307
->client
,
957 RX8025_REG_CTRL1
<< 4 | 0x08, 2, buf
);
959 dev_dbg(&client
->dev
, "read error %d\n", tmp
);
964 /* oscillator off? turn it on, so clock can tick. */
965 if (!(ds1307
->regs
[1] & RX8025_BIT_XST
)) {
966 ds1307
->regs
[1] |= RX8025_BIT_XST
;
967 i2c_smbus_write_byte_data(client
,
968 RX8025_REG_CTRL2
<< 4 | 0x08,
970 dev_warn(&client
->dev
,
971 "oscillator stop detected - SET TIME!\n");
974 if (ds1307
->regs
[1] & RX8025_BIT_PON
) {
975 ds1307
->regs
[1] &= ~RX8025_BIT_PON
;
976 i2c_smbus_write_byte_data(client
,
977 RX8025_REG_CTRL2
<< 4 | 0x08,
979 dev_warn(&client
->dev
, "power-on detected\n");
982 if (ds1307
->regs
[1] & RX8025_BIT_VDET
) {
983 ds1307
->regs
[1] &= ~RX8025_BIT_VDET
;
984 i2c_smbus_write_byte_data(client
,
985 RX8025_REG_CTRL2
<< 4 | 0x08,
987 dev_warn(&client
->dev
, "voltage drop detected\n");
990 /* make sure we are running in 24hour mode */
991 if (!(ds1307
->regs
[0] & RX8025_BIT_2412
)) {
994 /* switch to 24 hour mode */
995 i2c_smbus_write_byte_data(client
,
996 RX8025_REG_CTRL1
<< 4 | 0x08,
1000 tmp
= i2c_smbus_read_i2c_block_data(ds1307
->client
,
1001 RX8025_REG_CTRL1
<< 4 | 0x08, 2, buf
);
1003 dev_dbg(&client
->dev
, "read error %d\n", tmp
);
1009 hour
= bcd2bin(ds1307
->regs
[DS1307_REG_HOUR
]);
1012 if (ds1307
->regs
[DS1307_REG_HOUR
] & DS1307_BIT_PM
)
1015 i2c_smbus_write_byte_data(client
,
1016 DS1307_REG_HOUR
<< 4 | 0x08,
1021 ds1307
->offset
= 1; /* Seconds starts at 1 */
1024 rtc_ops
= &mcp794xx_rtc_ops
;
1025 if (ds1307
->client
->irq
> 0 && chip
->alarm
) {
1026 irq_handler
= mcp794xx_irq
;
1035 /* read RTC registers */
1036 tmp
= ds1307
->read_block_data(ds1307
->client
, ds1307
->offset
, 8, buf
);
1038 dev_dbg(&client
->dev
, "read error %d\n", tmp
);
1044 * minimal sanity checking; some chips (like DS1340) don't
1045 * specify the extra bits as must-be-zero, but there are
1046 * still a few values that are clearly out-of-range.
1048 tmp
= ds1307
->regs
[DS1307_REG_SECS
];
1049 switch (ds1307
->type
) {
1052 /* clock halted? turn it on, so clock can tick. */
1053 if (tmp
& DS1307_BIT_CH
) {
1054 i2c_smbus_write_byte_data(client
, DS1307_REG_SECS
, 0);
1055 dev_warn(&client
->dev
, "SET TIME!\n");
1060 /* clock halted? turn it on, so clock can tick. */
1061 if (tmp
& DS1307_BIT_CH
)
1062 i2c_smbus_write_byte_data(client
, DS1307_REG_SECS
, 0);
1064 /* oscillator fault? clear flag, and warn */
1065 if (ds1307
->regs
[DS1307_REG_CONTROL
] & DS1338_BIT_OSF
) {
1066 i2c_smbus_write_byte_data(client
, DS1307_REG_CONTROL
,
1067 ds1307
->regs
[DS1307_REG_CONTROL
]
1069 dev_warn(&client
->dev
, "SET TIME!\n");
1074 /* clock halted? turn it on, so clock can tick. */
1075 if (tmp
& DS1340_BIT_nEOSC
)
1076 i2c_smbus_write_byte_data(client
, DS1307_REG_SECS
, 0);
1078 tmp
= i2c_smbus_read_byte_data(client
, DS1340_REG_FLAG
);
1080 dev_dbg(&client
->dev
, "read error %d\n", tmp
);
1085 /* oscillator fault? clear flag, and warn */
1086 if (tmp
& DS1340_BIT_OSF
) {
1087 i2c_smbus_write_byte_data(client
, DS1340_REG_FLAG
, 0);
1088 dev_warn(&client
->dev
, "SET TIME!\n");
1092 /* make sure that the backup battery is enabled */
1093 if (!(ds1307
->regs
[DS1307_REG_WDAY
] & MCP794XX_BIT_VBATEN
)) {
1094 i2c_smbus_write_byte_data(client
, DS1307_REG_WDAY
,
1095 ds1307
->regs
[DS1307_REG_WDAY
]
1096 | MCP794XX_BIT_VBATEN
);
1099 /* clock halted? turn it on, so clock can tick. */
1100 if (!(tmp
& MCP794XX_BIT_ST
)) {
1101 i2c_smbus_write_byte_data(client
, DS1307_REG_SECS
,
1103 dev_warn(&client
->dev
, "SET TIME!\n");
1112 tmp
= ds1307
->regs
[DS1307_REG_HOUR
];
1113 switch (ds1307
->type
) {
1117 * NOTE: ignores century bits; fix before deploying
1118 * systems that will run through year 2100.
1124 if (!(tmp
& DS1307_BIT_12HR
))
1128 * Be sure we're in 24 hour mode. Multi-master systems
1131 tmp
= bcd2bin(tmp
& 0x1f);
1134 if (ds1307
->regs
[DS1307_REG_HOUR
] & DS1307_BIT_PM
)
1136 i2c_smbus_write_byte_data(client
,
1137 ds1307
->offset
+ DS1307_REG_HOUR
,
1141 device_set_wakeup_capable(&client
->dev
, want_irq
);
1142 ds1307
->rtc
= devm_rtc_device_register(&client
->dev
, client
->name
,
1143 rtc_ops
, THIS_MODULE
);
1144 if (IS_ERR(ds1307
->rtc
)) {
1145 return PTR_ERR(ds1307
->rtc
);
1149 struct device_node
*node
= client
->dev
.of_node
;
1151 err
= devm_request_threaded_irq(&client
->dev
,
1152 client
->irq
, NULL
, irq_handler
,
1153 IRQF_SHARED
| IRQF_ONESHOT
,
1154 ds1307
->rtc
->name
, client
);
1157 dev_err(&client
->dev
, "unable to request IRQ!\n");
1161 set_bit(HAS_ALARM
, &ds1307
->flags
);
1162 dev_dbg(&client
->dev
, "got IRQ %d\n", client
->irq
);
1164 /* Currently supported by OF code only! */
1168 err
= of_irq_get(node
, 1);
1170 if (err
== -EPROBE_DEFER
)
1174 ds1307
->wakeirq
= err
;
1176 err
= dev_pm_set_dedicated_wake_irq(&client
->dev
,
1179 dev_err(&client
->dev
, "unable to setup wakeIRQ %d!\n",
1186 if (chip
->nvram_size
) {
1188 ds1307
->nvram
= devm_kzalloc(&client
->dev
,
1189 sizeof(struct bin_attribute
),
1191 if (!ds1307
->nvram
) {
1192 dev_err(&client
->dev
, "cannot allocate memory for nvram sysfs\n");
1195 ds1307
->nvram
->attr
.name
= "nvram";
1196 ds1307
->nvram
->attr
.mode
= S_IRUGO
| S_IWUSR
;
1198 sysfs_bin_attr_init(ds1307
->nvram
);
1200 ds1307
->nvram
->read
= ds1307_nvram_read
;
1201 ds1307
->nvram
->write
= ds1307_nvram_write
;
1202 ds1307
->nvram
->size
= chip
->nvram_size
;
1203 ds1307
->nvram_offset
= chip
->nvram_offset
;
1205 err
= sysfs_create_bin_file(&client
->dev
.kobj
,
1208 dev_err(&client
->dev
,
1209 "unable to create sysfs file: %s\n",
1210 ds1307
->nvram
->attr
.name
);
1212 set_bit(HAS_NVRAM
, &ds1307
->flags
);
1213 dev_info(&client
->dev
, "%zu bytes nvram\n",
1214 ds1307
->nvram
->size
);
1225 static int ds1307_remove(struct i2c_client
*client
)
1227 struct ds1307
*ds1307
= i2c_get_clientdata(client
);
1229 if (ds1307
->wakeirq
)
1230 dev_pm_clear_wake_irq(&client
->dev
);
1232 if (test_and_clear_bit(HAS_NVRAM
, &ds1307
->flags
))
1233 sysfs_remove_bin_file(&client
->dev
.kobj
, ds1307
->nvram
);
1238 static struct i2c_driver ds1307_driver
= {
1240 .name
= "rtc-ds1307",
1242 .probe
= ds1307_probe
,
1243 .remove
= ds1307_remove
,
1244 .id_table
= ds1307_id
,
1247 module_i2c_driver(ds1307_driver
);
1249 MODULE_DESCRIPTION("RTC driver for DS1307 and similar chips");
1250 MODULE_LICENSE("GPL");