2 * An I2C driver for Ricoh RS5C372, R2025S/D and RV5C38[67] RTCs
4 * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
5 * Copyright (C) 2006 Tower Technologies
6 * Copyright (C) 2008 Paul Mundt
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/i2c.h>
14 #include <linux/rtc.h>
15 #include <linux/bcd.h>
17 #define DRV_VERSION "0.6"
21 * Ricoh has a family of I2C based RTCs, which differ only slightly from
22 * each other. Differences center on pinout (e.g. how many interrupts,
23 * output clock, etc) and how the control registers are used. The '372
24 * is significant only because that's the one this driver first supported.
26 #define RS5C372_REG_SECS 0
27 #define RS5C372_REG_MINS 1
28 #define RS5C372_REG_HOURS 2
29 #define RS5C372_REG_WDAY 3
30 #define RS5C372_REG_DAY 4
31 #define RS5C372_REG_MONTH 5
32 #define RS5C372_REG_YEAR 6
33 #define RS5C372_REG_TRIM 7
34 # define RS5C372_TRIM_XSL 0x80
35 # define RS5C372_TRIM_MASK 0x7F
37 #define RS5C_REG_ALARM_A_MIN 8 /* or ALARM_W */
38 #define RS5C_REG_ALARM_A_HOURS 9
39 #define RS5C_REG_ALARM_A_WDAY 10
41 #define RS5C_REG_ALARM_B_MIN 11 /* or ALARM_D */
42 #define RS5C_REG_ALARM_B_HOURS 12
43 #define RS5C_REG_ALARM_B_WDAY 13 /* (ALARM_B only) */
45 #define RS5C_REG_CTRL1 14
46 # define RS5C_CTRL1_AALE (1 << 7) /* or WALE */
47 # define RS5C_CTRL1_BALE (1 << 6) /* or DALE */
48 # define RV5C387_CTRL1_24 (1 << 5)
49 # define RS5C372A_CTRL1_SL1 (1 << 5)
50 # define RS5C_CTRL1_CT_MASK (7 << 0)
51 # define RS5C_CTRL1_CT0 (0 << 0) /* no periodic irq */
52 # define RS5C_CTRL1_CT4 (4 << 0) /* 1 Hz level irq */
53 #define RS5C_REG_CTRL2 15
54 # define RS5C372_CTRL2_24 (1 << 5)
55 # define R2025_CTRL2_XST (1 << 5)
56 # define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */
57 # define RS5C_CTRL2_CTFG (1 << 2)
58 # define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */
59 # define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */
62 /* to read (style 1) or write registers starting at R */
63 #define RS5C_ADDR(R) (((R) << 4) | 0)
75 static const struct i2c_device_id rs5c372_id
[] = {
76 { "r2025sd", rtc_r2025sd
},
77 { "rs5c372a", rtc_rs5c372a
},
78 { "rs5c372b", rtc_rs5c372b
},
79 { "rv5c386", rtc_rv5c386
},
80 { "rv5c387a", rtc_rv5c387a
},
83 MODULE_DEVICE_TABLE(i2c
, rs5c372_id
);
85 /* REVISIT: this assumes that:
86 * - we're in the 21st century, so it's safe to ignore the century
87 * bit for rv5c38[67] (REG_MONTH bit 7);
88 * - we should use ALARM_A not ALARM_B (may be wrong on some boards)
91 struct i2c_client
*client
;
92 struct rtc_device
*rtc
;
101 static int rs5c_get_regs(struct rs5c372
*rs5c
)
103 struct i2c_client
*client
= rs5c
->client
;
104 struct i2c_msg msgs
[] = {
105 { client
->addr
, I2C_M_RD
, sizeof rs5c
->buf
, rs5c
->buf
},
108 /* This implements the third reading method from the datasheet, using
109 * an internal address that's reset after each transaction (by STOP)
110 * to 0x0f ... so we read extra registers, and skip the first one.
112 * The first method doesn't work with the iop3xx adapter driver, on at
113 * least 80219 chips; this works around that bug.
115 * The third method on the other hand doesn't work for the SMBus-only
116 * configurations, so we use the the first method there, stripping off
117 * the extra register in the process.
120 int addr
= RS5C_ADDR(RS5C372_REG_SECS
);
121 int size
= sizeof(rs5c
->buf
) - 1;
123 if (i2c_smbus_read_i2c_block_data(client
, addr
, size
,
124 rs5c
->buf
+ 1) != size
) {
125 dev_warn(&client
->dev
, "can't read registers\n");
129 if ((i2c_transfer(client
->adapter
, msgs
, 1)) != 1) {
130 dev_warn(&client
->dev
, "can't read registers\n");
135 dev_dbg(&client
->dev
,
136 "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
137 "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
138 rs5c
->regs
[0], rs5c
->regs
[1], rs5c
->regs
[2], rs5c
->regs
[3],
139 rs5c
->regs
[4], rs5c
->regs
[5], rs5c
->regs
[6], rs5c
->regs
[7],
140 rs5c
->regs
[8], rs5c
->regs
[9], rs5c
->regs
[10], rs5c
->regs
[11],
141 rs5c
->regs
[12], rs5c
->regs
[13], rs5c
->regs
[14], rs5c
->regs
[15]);
146 static unsigned rs5c_reg2hr(struct rs5c372
*rs5c
, unsigned reg
)
151 return bcd2bin(reg
& 0x3f);
153 hour
= bcd2bin(reg
& 0x1f);
161 static unsigned rs5c_hr2reg(struct rs5c372
*rs5c
, unsigned hour
)
164 return bin2bcd(hour
);
167 return 0x20 | bin2bcd(hour
- 12);
169 return 0x20 | bin2bcd(12);
172 return bin2bcd(hour
);
175 static int rs5c372_get_datetime(struct i2c_client
*client
, struct rtc_time
*tm
)
177 struct rs5c372
*rs5c
= i2c_get_clientdata(client
);
178 int status
= rs5c_get_regs(rs5c
);
183 tm
->tm_sec
= bcd2bin(rs5c
->regs
[RS5C372_REG_SECS
] & 0x7f);
184 tm
->tm_min
= bcd2bin(rs5c
->regs
[RS5C372_REG_MINS
] & 0x7f);
185 tm
->tm_hour
= rs5c_reg2hr(rs5c
, rs5c
->regs
[RS5C372_REG_HOURS
]);
187 tm
->tm_wday
= bcd2bin(rs5c
->regs
[RS5C372_REG_WDAY
] & 0x07);
188 tm
->tm_mday
= bcd2bin(rs5c
->regs
[RS5C372_REG_DAY
] & 0x3f);
190 /* tm->tm_mon is zero-based */
191 tm
->tm_mon
= bcd2bin(rs5c
->regs
[RS5C372_REG_MONTH
] & 0x1f) - 1;
193 /* year is 1900 + tm->tm_year */
194 tm
->tm_year
= bcd2bin(rs5c
->regs
[RS5C372_REG_YEAR
]) + 100;
196 dev_dbg(&client
->dev
, "%s: tm is secs=%d, mins=%d, hours=%d, "
197 "mday=%d, mon=%d, year=%d, wday=%d\n",
199 tm
->tm_sec
, tm
->tm_min
, tm
->tm_hour
,
200 tm
->tm_mday
, tm
->tm_mon
, tm
->tm_year
, tm
->tm_wday
);
202 /* rtc might need initialization */
203 return rtc_valid_tm(tm
);
206 static int rs5c372_set_datetime(struct i2c_client
*client
, struct rtc_time
*tm
)
208 struct rs5c372
*rs5c
= i2c_get_clientdata(client
);
209 unsigned char buf
[8];
212 dev_dbg(&client
->dev
, "%s: tm is secs=%d, mins=%d, hours=%d "
213 "mday=%d, mon=%d, year=%d, wday=%d\n",
215 tm
->tm_sec
, tm
->tm_min
, tm
->tm_hour
,
216 tm
->tm_mday
, tm
->tm_mon
, tm
->tm_year
, tm
->tm_wday
);
218 addr
= RS5C_ADDR(RS5C372_REG_SECS
);
219 buf
[0] = bin2bcd(tm
->tm_sec
);
220 buf
[1] = bin2bcd(tm
->tm_min
);
221 buf
[2] = rs5c_hr2reg(rs5c
, tm
->tm_hour
);
222 buf
[3] = bin2bcd(tm
->tm_wday
);
223 buf
[4] = bin2bcd(tm
->tm_mday
);
224 buf
[5] = bin2bcd(tm
->tm_mon
+ 1);
225 buf
[6] = bin2bcd(tm
->tm_year
- 100);
227 if (i2c_smbus_write_i2c_block_data(client
, addr
, sizeof(buf
), buf
) < 0) {
228 dev_err(&client
->dev
, "%s: write error\n", __func__
);
235 #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
239 #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
244 static int rs5c372_get_trim(struct i2c_client
*client
, int *osc
, int *trim
)
246 struct rs5c372
*rs5c372
= i2c_get_clientdata(client
);
247 u8 tmp
= rs5c372
->regs
[RS5C372_REG_TRIM
];
250 *osc
= (tmp
& RS5C372_TRIM_XSL
) ? 32000 : 32768;
253 dev_dbg(&client
->dev
, "%s: raw trim=%x\n", __func__
, tmp
);
254 tmp
&= RS5C372_TRIM_MASK
;
259 t
= (~t
| (s8
)0xc0) + 1;
273 static int rs5c372_rtc_read_time(struct device
*dev
, struct rtc_time
*tm
)
275 return rs5c372_get_datetime(to_i2c_client(dev
), tm
);
278 static int rs5c372_rtc_set_time(struct device
*dev
, struct rtc_time
*tm
)
280 return rs5c372_set_datetime(to_i2c_client(dev
), tm
);
283 #if defined(CONFIG_RTC_INTF_DEV) || defined(CONFIG_RTC_INTF_DEV_MODULE)
286 rs5c_rtc_ioctl(struct device
*dev
, unsigned int cmd
, unsigned long arg
)
288 struct i2c_client
*client
= to_i2c_client(dev
);
289 struct rs5c372
*rs5c
= i2c_get_clientdata(client
);
293 buf
= rs5c
->regs
[RS5C_REG_CTRL1
];
297 /* some 327a modes use a different IRQ pin for 1Hz irqs */
298 if (rs5c
->type
== rtc_rs5c372a
299 && (buf
& RS5C372A_CTRL1_SL1
))
303 /* these irq management calls only make sense for chips
304 * which are wired up to an IRQ.
313 status
= rs5c_get_regs(rs5c
);
317 addr
= RS5C_ADDR(RS5C_REG_CTRL1
);
319 case RTC_AIE_OFF
: /* alarm off */
320 buf
&= ~RS5C_CTRL1_AALE
;
322 case RTC_AIE_ON
: /* alarm on */
323 buf
|= RS5C_CTRL1_AALE
;
325 case RTC_UIE_OFF
: /* update off */
326 buf
&= ~RS5C_CTRL1_CT_MASK
;
328 case RTC_UIE_ON
: /* update on */
329 buf
&= ~RS5C_CTRL1_CT_MASK
;
330 buf
|= RS5C_CTRL1_CT4
;
334 if (i2c_smbus_write_byte_data(client
, addr
, buf
) < 0) {
335 printk(KERN_WARNING
"%s: can't update alarm\n",
339 rs5c
->regs
[RS5C_REG_CTRL1
] = buf
;
345 #define rs5c_rtc_ioctl NULL
349 /* NOTE: Since RTC_WKALM_{RD,SET} were originally defined for EFI,
350 * which only exposes a polled programming interface; and since
351 * these calls map directly to those EFI requests; we don't demand
352 * we have an IRQ for this chip when we go through this API.
354 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
355 * though, managed through RTC_AIE_{ON,OFF} requests.
358 static int rs5c_read_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
360 struct i2c_client
*client
= to_i2c_client(dev
);
361 struct rs5c372
*rs5c
= i2c_get_clientdata(client
);
364 status
= rs5c_get_regs(rs5c
);
368 /* report alarm time */
370 t
->time
.tm_min
= bcd2bin(rs5c
->regs
[RS5C_REG_ALARM_A_MIN
] & 0x7f);
371 t
->time
.tm_hour
= rs5c_reg2hr(rs5c
, rs5c
->regs
[RS5C_REG_ALARM_A_HOURS
]);
372 t
->time
.tm_mday
= -1;
374 t
->time
.tm_year
= -1;
375 t
->time
.tm_wday
= -1;
376 t
->time
.tm_yday
= -1;
377 t
->time
.tm_isdst
= -1;
380 t
->enabled
= !!(rs5c
->regs
[RS5C_REG_CTRL1
] & RS5C_CTRL1_AALE
);
381 t
->pending
= !!(rs5c
->regs
[RS5C_REG_CTRL2
] & RS5C_CTRL2_AAFG
);
386 static int rs5c_set_alarm(struct device
*dev
, struct rtc_wkalrm
*t
)
388 struct i2c_client
*client
= to_i2c_client(dev
);
389 struct rs5c372
*rs5c
= i2c_get_clientdata(client
);
391 unsigned char buf
[3];
393 /* only handle up to 24 hours in the future, like RTC_ALM_SET */
394 if (t
->time
.tm_mday
!= -1
395 || t
->time
.tm_mon
!= -1
396 || t
->time
.tm_year
!= -1)
399 /* REVISIT: round up tm_sec */
401 /* if needed, disable irq (clears pending status) */
402 status
= rs5c_get_regs(rs5c
);
405 if (rs5c
->regs
[RS5C_REG_CTRL1
] & RS5C_CTRL1_AALE
) {
406 addr
= RS5C_ADDR(RS5C_REG_CTRL1
);
407 buf
[0] = rs5c
->regs
[RS5C_REG_CTRL1
] & ~RS5C_CTRL1_AALE
;
408 if (i2c_smbus_write_byte_data(client
, addr
, buf
[0]) < 0) {
409 pr_debug("%s: can't disable alarm\n", rs5c
->rtc
->name
);
412 rs5c
->regs
[RS5C_REG_CTRL1
] = buf
[0];
416 buf
[0] = bin2bcd(t
->time
.tm_min
);
417 buf
[1] = rs5c_hr2reg(rs5c
, t
->time
.tm_hour
);
418 buf
[2] = 0x7f; /* any/all days */
420 for (i
= 0; i
< sizeof(buf
); i
++) {
421 addr
= RS5C_ADDR(RS5C_REG_ALARM_A_MIN
+ i
);
422 if (i2c_smbus_write_byte_data(client
, addr
, buf
[i
]) < 0) {
423 pr_debug("%s: can't set alarm time\n", rs5c
->rtc
->name
);
428 /* ... and maybe enable its irq */
430 addr
= RS5C_ADDR(RS5C_REG_CTRL1
);
431 buf
[0] = rs5c
->regs
[RS5C_REG_CTRL1
] | RS5C_CTRL1_AALE
;
432 if (i2c_smbus_write_byte_data(client
, addr
, buf
[0]) < 0)
433 printk(KERN_WARNING
"%s: can't enable alarm\n",
435 rs5c
->regs
[RS5C_REG_CTRL1
] = buf
[0];
441 #if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
443 static int rs5c372_rtc_proc(struct device
*dev
, struct seq_file
*seq
)
447 err
= rs5c372_get_trim(to_i2c_client(dev
), &osc
, &trim
);
449 seq_printf(seq
, "crystal\t\t: %d.%03d KHz\n",
450 osc
/ 1000, osc
% 1000);
451 seq_printf(seq
, "trim\t\t: %d\n", trim
);
458 #define rs5c372_rtc_proc NULL
461 static const struct rtc_class_ops rs5c372_rtc_ops
= {
462 .proc
= rs5c372_rtc_proc
,
463 .ioctl
= rs5c_rtc_ioctl
,
464 .read_time
= rs5c372_rtc_read_time
,
465 .set_time
= rs5c372_rtc_set_time
,
466 .read_alarm
= rs5c_read_alarm
,
467 .set_alarm
= rs5c_set_alarm
,
470 #if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
472 static ssize_t
rs5c372_sysfs_show_trim(struct device
*dev
,
473 struct device_attribute
*attr
, char *buf
)
477 err
= rs5c372_get_trim(to_i2c_client(dev
), NULL
, &trim
);
481 return sprintf(buf
, "%d\n", trim
);
483 static DEVICE_ATTR(trim
, S_IRUGO
, rs5c372_sysfs_show_trim
, NULL
);
485 static ssize_t
rs5c372_sysfs_show_osc(struct device
*dev
,
486 struct device_attribute
*attr
, char *buf
)
490 err
= rs5c372_get_trim(to_i2c_client(dev
), &osc
, NULL
);
494 return sprintf(buf
, "%d.%03d KHz\n", osc
/ 1000, osc
% 1000);
496 static DEVICE_ATTR(osc
, S_IRUGO
, rs5c372_sysfs_show_osc
, NULL
);
498 static int rs5c_sysfs_register(struct device
*dev
)
502 err
= device_create_file(dev
, &dev_attr_trim
);
505 err
= device_create_file(dev
, &dev_attr_osc
);
507 device_remove_file(dev
, &dev_attr_trim
);
512 static void rs5c_sysfs_unregister(struct device
*dev
)
514 device_remove_file(dev
, &dev_attr_trim
);
515 device_remove_file(dev
, &dev_attr_osc
);
519 static int rs5c_sysfs_register(struct device
*dev
)
524 static void rs5c_sysfs_unregister(struct device
*dev
)
530 static struct i2c_driver rs5c372_driver
;
532 static int rs5c_oscillator_setup(struct rs5c372
*rs5c372
)
534 unsigned char buf
[2];
535 int addr
, i
, ret
= 0;
537 if (rs5c372
->type
== rtc_r2025sd
) {
538 if (!(rs5c372
->regs
[RS5C_REG_CTRL2
] & R2025_CTRL2_XST
))
540 rs5c372
->regs
[RS5C_REG_CTRL2
] &= ~R2025_CTRL2_XST
;
542 if (!(rs5c372
->regs
[RS5C_REG_CTRL2
] & RS5C_CTRL2_XSTP
))
544 rs5c372
->regs
[RS5C_REG_CTRL2
] &= ~RS5C_CTRL2_XSTP
;
547 addr
= RS5C_ADDR(RS5C_REG_CTRL1
);
548 buf
[0] = rs5c372
->regs
[RS5C_REG_CTRL1
];
549 buf
[1] = rs5c372
->regs
[RS5C_REG_CTRL2
];
552 switch (rs5c372
->type
) {
555 buf
[1] |= RS5C372_CTRL2_24
;
561 buf
[0] |= RV5C387_CTRL1_24
;
569 for (i
= 0; i
< sizeof(buf
); i
++) {
570 addr
= RS5C_ADDR(RS5C_REG_CTRL1
+ i
);
571 ret
= i2c_smbus_write_byte_data(rs5c372
->client
, addr
, buf
[i
]);
572 if (unlikely(ret
< 0))
576 rs5c372
->regs
[RS5C_REG_CTRL1
] = buf
[0];
577 rs5c372
->regs
[RS5C_REG_CTRL2
] = buf
[1];
582 static int rs5c372_probe(struct i2c_client
*client
,
583 const struct i2c_device_id
*id
)
587 struct rs5c372
*rs5c372
;
590 dev_dbg(&client
->dev
, "%s\n", __func__
);
592 if (!i2c_check_functionality(client
->adapter
, I2C_FUNC_I2C
|
593 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_I2C_BLOCK
)) {
595 * If we don't have any master mode adapter, try breaking
596 * it down in to the barest of capabilities.
598 if (i2c_check_functionality(client
->adapter
,
599 I2C_FUNC_SMBUS_BYTE_DATA
|
600 I2C_FUNC_SMBUS_I2C_BLOCK
))
603 /* Still no good, give up */
609 if (!(rs5c372
= kzalloc(sizeof(struct rs5c372
), GFP_KERNEL
))) {
614 rs5c372
->client
= client
;
615 i2c_set_clientdata(client
, rs5c372
);
616 rs5c372
->type
= id
->driver_data
;
618 /* we read registers 0x0f then 0x00-0x0f; skip the first one */
619 rs5c372
->regs
= &rs5c372
->buf
[1];
620 rs5c372
->smbus
= smbus_mode
;
622 err
= rs5c_get_regs(rs5c372
);
626 /* clock may be set for am/pm or 24 hr time */
627 switch (rs5c372
->type
) {
630 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
631 * so does periodic irq, except some 327a modes.
633 if (rs5c372
->regs
[RS5C_REG_CTRL2
] & RS5C372_CTRL2_24
)
639 if (rs5c372
->regs
[RS5C_REG_CTRL1
] & RV5C387_CTRL1_24
)
641 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
642 * irq, on both 386 and 387
646 dev_err(&client
->dev
, "unknown RTC type\n");
650 /* if the oscillator lost power and no other software (like
651 * the bootloader) set it up, do it here.
653 * The R2025S/D does this a little differently than the other
654 * parts, so we special case that..
656 err
= rs5c_oscillator_setup(rs5c372
);
657 if (unlikely(err
< 0)) {
658 dev_err(&client
->dev
, "setup error\n");
662 if (rs5c372_get_datetime(client
, &tm
) < 0)
663 dev_warn(&client
->dev
, "clock needs to be set\n");
665 dev_info(&client
->dev
, "%s found, %s, driver version " DRV_VERSION
"\n",
666 ({ char *s
; switch (rs5c372
->type
) {
667 case rtc_r2025sd
: s
= "r2025sd"; break;
668 case rtc_rs5c372a
: s
= "rs5c372a"; break;
669 case rtc_rs5c372b
: s
= "rs5c372b"; break;
670 case rtc_rv5c386
: s
= "rv5c386"; break;
671 case rtc_rv5c387a
: s
= "rv5c387a"; break;
672 default: s
= "chip"; break;
674 rs5c372
->time24
? "24hr" : "am/pm"
677 /* REVISIT use client->irq to register alarm irq ... */
679 rs5c372
->rtc
= rtc_device_register(rs5c372_driver
.driver
.name
,
680 &client
->dev
, &rs5c372_rtc_ops
, THIS_MODULE
);
682 if (IS_ERR(rs5c372
->rtc
)) {
683 err
= PTR_ERR(rs5c372
->rtc
);
687 err
= rs5c_sysfs_register(&client
->dev
);
694 rtc_device_unregister(rs5c372
->rtc
);
703 static int rs5c372_remove(struct i2c_client
*client
)
705 struct rs5c372
*rs5c372
= i2c_get_clientdata(client
);
707 rtc_device_unregister(rs5c372
->rtc
);
708 rs5c_sysfs_unregister(&client
->dev
);
713 static struct i2c_driver rs5c372_driver
= {
715 .name
= "rtc-rs5c372",
717 .probe
= rs5c372_probe
,
718 .remove
= rs5c372_remove
,
719 .id_table
= rs5c372_id
,
722 static __init
int rs5c372_init(void)
724 return i2c_add_driver(&rs5c372_driver
);
727 static __exit
void rs5c372_exit(void)
729 i2c_del_driver(&rs5c372_driver
);
732 module_init(rs5c372_init
);
733 module_exit(rs5c372_exit
);
736 "Pavel Mironchik <pmironchik@optifacio.net>, "
737 "Alessandro Zummo <a.zummo@towertech.it>, "
738 "Paul Mundt <lethal@linux-sh.org>");
739 MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
740 MODULE_LICENSE("GPL");
741 MODULE_VERSION(DRV_VERSION
);