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1/*
2 * An I2C driver for Ricoh RS5C372, R2025S/D and RV5C38[67] RTCs
3 *
4 * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
5 * Copyright (C) 2006 Tower Technologies
6 * Copyright (C) 2008 Paul Mundt
7 *
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.
11 */
12
13#include <linux/i2c.h>
14#include <linux/rtc.h>
15#include <linux/bcd.h>
16#include <linux/slab.h>
17#include <linux/module.h>
18
19#define DRV_VERSION "0.6"
20
21
22/*
23 * Ricoh has a family of I2C based RTCs, which differ only slightly from
24 * each other. Differences center on pinout (e.g. how many interrupts,
25 * output clock, etc) and how the control registers are used. The '372
26 * is significant only because that's the one this driver first supported.
27 */
28#define RS5C372_REG_SECS 0
29#define RS5C372_REG_MINS 1
30#define RS5C372_REG_HOURS 2
31#define RS5C372_REG_WDAY 3
32#define RS5C372_REG_DAY 4
33#define RS5C372_REG_MONTH 5
34#define RS5C372_REG_YEAR 6
35#define RS5C372_REG_TRIM 7
36# define RS5C372_TRIM_XSL 0x80
37# define RS5C372_TRIM_MASK 0x7F
38
39#define RS5C_REG_ALARM_A_MIN 8 /* or ALARM_W */
40#define RS5C_REG_ALARM_A_HOURS 9
41#define RS5C_REG_ALARM_A_WDAY 10
42
43#define RS5C_REG_ALARM_B_MIN 11 /* or ALARM_D */
44#define RS5C_REG_ALARM_B_HOURS 12
45#define RS5C_REG_ALARM_B_WDAY 13 /* (ALARM_B only) */
46
47#define RS5C_REG_CTRL1 14
48# define RS5C_CTRL1_AALE (1 << 7) /* or WALE */
49# define RS5C_CTRL1_BALE (1 << 6) /* or DALE */
50# define RV5C387_CTRL1_24 (1 << 5)
51# define RS5C372A_CTRL1_SL1 (1 << 5)
52# define RS5C_CTRL1_CT_MASK (7 << 0)
53# define RS5C_CTRL1_CT0 (0 << 0) /* no periodic irq */
54# define RS5C_CTRL1_CT4 (4 << 0) /* 1 Hz level irq */
55#define RS5C_REG_CTRL2 15
56# define RS5C372_CTRL2_24 (1 << 5)
57# define R2025_CTRL2_XST (1 << 5)
58# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */
59# define RS5C_CTRL2_CTFG (1 << 2)
60# define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */
61# define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */
62
63
64/* to read (style 1) or write registers starting at R */
65#define RS5C_ADDR(R) (((R) << 4) | 0)
66
67
68enum rtc_type {
69 rtc_undef = 0,
70 rtc_r2025sd,
71 rtc_rs5c372a,
72 rtc_rs5c372b,
73 rtc_rv5c386,
74 rtc_rv5c387a,
75};
76
77static const struct i2c_device_id rs5c372_id[] = {
78 { "r2025sd", rtc_r2025sd },
79 { "rs5c372a", rtc_rs5c372a },
80 { "rs5c372b", rtc_rs5c372b },
81 { "rv5c386", rtc_rv5c386 },
82 { "rv5c387a", rtc_rv5c387a },
83 { }
84};
85MODULE_DEVICE_TABLE(i2c, rs5c372_id);
86
87/* REVISIT: this assumes that:
88 * - we're in the 21st century, so it's safe to ignore the century
89 * bit for rv5c38[67] (REG_MONTH bit 7);
90 * - we should use ALARM_A not ALARM_B (may be wrong on some boards)
91 */
92struct rs5c372 {
93 struct i2c_client *client;
94 struct rtc_device *rtc;
95 enum rtc_type type;
96 unsigned time24:1;
97 unsigned has_irq:1;
98 unsigned smbus:1;
99 char buf[17];
100 char *regs;
101};
102
103static int rs5c_get_regs(struct rs5c372 *rs5c)
104{
105 struct i2c_client *client = rs5c->client;
106 struct i2c_msg msgs[] = {
107 { client->addr, I2C_M_RD, sizeof rs5c->buf, rs5c->buf },
108 };
109
110 /* This implements the third reading method from the datasheet, using
111 * an internal address that's reset after each transaction (by STOP)
112 * to 0x0f ... so we read extra registers, and skip the first one.
113 *
114 * The first method doesn't work with the iop3xx adapter driver, on at
115 * least 80219 chips; this works around that bug.
116 *
117 * The third method on the other hand doesn't work for the SMBus-only
118 * configurations, so we use the the first method there, stripping off
119 * the extra register in the process.
120 */
121 if (rs5c->smbus) {
122 int addr = RS5C_ADDR(RS5C372_REG_SECS);
123 int size = sizeof(rs5c->buf) - 1;
124
125 if (i2c_smbus_read_i2c_block_data(client, addr, size,
126 rs5c->buf + 1) != size) {
127 dev_warn(&client->dev, "can't read registers\n");
128 return -EIO;
129 }
130 } else {
131 if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
132 dev_warn(&client->dev, "can't read registers\n");
133 return -EIO;
134 }
135 }
136
137 dev_dbg(&client->dev,
138 "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
139 "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
140 rs5c->regs[0], rs5c->regs[1], rs5c->regs[2], rs5c->regs[3],
141 rs5c->regs[4], rs5c->regs[5], rs5c->regs[6], rs5c->regs[7],
142 rs5c->regs[8], rs5c->regs[9], rs5c->regs[10], rs5c->regs[11],
143 rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
144
145 return 0;
146}
147
148static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
149{
150 unsigned hour;
151
152 if (rs5c->time24)
153 return bcd2bin(reg & 0x3f);
154
155 hour = bcd2bin(reg & 0x1f);
156 if (hour == 12)
157 hour = 0;
158 if (reg & 0x20)
159 hour += 12;
160 return hour;
161}
162
163static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
164{
165 if (rs5c->time24)
166 return bin2bcd(hour);
167
168 if (hour > 12)
169 return 0x20 | bin2bcd(hour - 12);
170 if (hour == 12)
171 return 0x20 | bin2bcd(12);
172 if (hour == 0)
173 return bin2bcd(12);
174 return bin2bcd(hour);
175}
176
177static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
178{
179 struct rs5c372 *rs5c = i2c_get_clientdata(client);
180 int status = rs5c_get_regs(rs5c);
181
182 if (status < 0)
183 return status;
184
185 tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
186 tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
187 tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
188
189 tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
190 tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
191
192 /* tm->tm_mon is zero-based */
193 tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
194
195 /* year is 1900 + tm->tm_year */
196 tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
197
198 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
199 "mday=%d, mon=%d, year=%d, wday=%d\n",
200 __func__,
201 tm->tm_sec, tm->tm_min, tm->tm_hour,
202 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
203
204 /* rtc might need initialization */
205 return rtc_valid_tm(tm);
206}
207
208static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
209{
210 struct rs5c372 *rs5c = i2c_get_clientdata(client);
211 unsigned char buf[7];
212 int addr;
213
214 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
215 "mday=%d, mon=%d, year=%d, wday=%d\n",
216 __func__,
217 tm->tm_sec, tm->tm_min, tm->tm_hour,
218 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
219
220 addr = RS5C_ADDR(RS5C372_REG_SECS);
221 buf[0] = bin2bcd(tm->tm_sec);
222 buf[1] = bin2bcd(tm->tm_min);
223 buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
224 buf[3] = bin2bcd(tm->tm_wday);
225 buf[4] = bin2bcd(tm->tm_mday);
226 buf[5] = bin2bcd(tm->tm_mon + 1);
227 buf[6] = bin2bcd(tm->tm_year - 100);
228
229 if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
230 dev_err(&client->dev, "%s: write error\n", __func__);
231 return -EIO;
232 }
233
234 return 0;
235}
236
237#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
238#define NEED_TRIM
239#endif
240
241#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
242#define NEED_TRIM
243#endif
244
245#ifdef NEED_TRIM
246static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
247{
248 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
249 u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
250
251 if (osc)
252 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
253
254 if (trim) {
255 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
256 tmp &= RS5C372_TRIM_MASK;
257 if (tmp & 0x3e) {
258 int t = tmp & 0x3f;
259
260 if (tmp & 0x40)
261 t = (~t | (s8)0xc0) + 1;
262 else
263 t = t - 1;
264
265 tmp = t * 2;
266 } else
267 tmp = 0;
268 *trim = tmp;
269 }
270
271 return 0;
272}
273#endif
274
275static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
276{
277 return rs5c372_get_datetime(to_i2c_client(dev), tm);
278}
279
280static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
281{
282 return rs5c372_set_datetime(to_i2c_client(dev), tm);
283}
284
285
286static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
287{
288 struct i2c_client *client = to_i2c_client(dev);
289 struct rs5c372 *rs5c = i2c_get_clientdata(client);
290 unsigned char buf;
291 int status, addr;
292
293 buf = rs5c->regs[RS5C_REG_CTRL1];
294
295 if (!rs5c->has_irq)
296 return -EINVAL;
297
298 status = rs5c_get_regs(rs5c);
299 if (status < 0)
300 return status;
301
302 addr = RS5C_ADDR(RS5C_REG_CTRL1);
303 if (enabled)
304 buf |= RS5C_CTRL1_AALE;
305 else
306 buf &= ~RS5C_CTRL1_AALE;
307
308 if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
309 printk(KERN_WARNING "%s: can't update alarm\n",
310 rs5c->rtc->name);
311 status = -EIO;
312 } else
313 rs5c->regs[RS5C_REG_CTRL1] = buf;
314
315 return status;
316}
317
318
319/* NOTE: Since RTC_WKALM_{RD,SET} were originally defined for EFI,
320 * which only exposes a polled programming interface; and since
321 * these calls map directly to those EFI requests; we don't demand
322 * we have an IRQ for this chip when we go through this API.
323 *
324 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
325 * though, managed through RTC_AIE_{ON,OFF} requests.
326 */
327
328static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
329{
330 struct i2c_client *client = to_i2c_client(dev);
331 struct rs5c372 *rs5c = i2c_get_clientdata(client);
332 int status;
333
334 status = rs5c_get_regs(rs5c);
335 if (status < 0)
336 return status;
337
338 /* report alarm time */
339 t->time.tm_sec = 0;
340 t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
341 t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
342 t->time.tm_mday = -1;
343 t->time.tm_mon = -1;
344 t->time.tm_year = -1;
345 t->time.tm_wday = -1;
346 t->time.tm_yday = -1;
347 t->time.tm_isdst = -1;
348
349 /* ... and status */
350 t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
351 t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
352
353 return 0;
354}
355
356static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
357{
358 struct i2c_client *client = to_i2c_client(dev);
359 struct rs5c372 *rs5c = i2c_get_clientdata(client);
360 int status, addr, i;
361 unsigned char buf[3];
362
363 /* only handle up to 24 hours in the future, like RTC_ALM_SET */
364 if (t->time.tm_mday != -1
365 || t->time.tm_mon != -1
366 || t->time.tm_year != -1)
367 return -EINVAL;
368
369 /* REVISIT: round up tm_sec */
370
371 /* if needed, disable irq (clears pending status) */
372 status = rs5c_get_regs(rs5c);
373 if (status < 0)
374 return status;
375 if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
376 addr = RS5C_ADDR(RS5C_REG_CTRL1);
377 buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
378 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
379 pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
380 return -EIO;
381 }
382 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
383 }
384
385 /* set alarm */
386 buf[0] = bin2bcd(t->time.tm_min);
387 buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
388 buf[2] = 0x7f; /* any/all days */
389
390 for (i = 0; i < sizeof(buf); i++) {
391 addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
392 if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
393 pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
394 return -EIO;
395 }
396 }
397
398 /* ... and maybe enable its irq */
399 if (t->enabled) {
400 addr = RS5C_ADDR(RS5C_REG_CTRL1);
401 buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
402 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
403 printk(KERN_WARNING "%s: can't enable alarm\n",
404 rs5c->rtc->name);
405 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
406 }
407
408 return 0;
409}
410
411#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
412
413static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
414{
415 int err, osc, trim;
416
417 err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
418 if (err == 0) {
419 seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
420 osc / 1000, osc % 1000);
421 seq_printf(seq, "trim\t\t: %d\n", trim);
422 }
423
424 return 0;
425}
426
427#else
428#define rs5c372_rtc_proc NULL
429#endif
430
431static const struct rtc_class_ops rs5c372_rtc_ops = {
432 .proc = rs5c372_rtc_proc,
433 .read_time = rs5c372_rtc_read_time,
434 .set_time = rs5c372_rtc_set_time,
435 .read_alarm = rs5c_read_alarm,
436 .set_alarm = rs5c_set_alarm,
437 .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
438};
439
440#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
441
442static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
443 struct device_attribute *attr, char *buf)
444{
445 int err, trim;
446
447 err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
448 if (err)
449 return err;
450
451 return sprintf(buf, "%d\n", trim);
452}
453static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
454
455static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
456 struct device_attribute *attr, char *buf)
457{
458 int err, osc;
459
460 err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
461 if (err)
462 return err;
463
464 return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
465}
466static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
467
468static int rs5c_sysfs_register(struct device *dev)
469{
470 int err;
471
472 err = device_create_file(dev, &dev_attr_trim);
473 if (err)
474 return err;
475 err = device_create_file(dev, &dev_attr_osc);
476 if (err)
477 device_remove_file(dev, &dev_attr_trim);
478
479 return err;
480}
481
482static void rs5c_sysfs_unregister(struct device *dev)
483{
484 device_remove_file(dev, &dev_attr_trim);
485 device_remove_file(dev, &dev_attr_osc);
486}
487
488#else
489static int rs5c_sysfs_register(struct device *dev)
490{
491 return 0;
492}
493
494static void rs5c_sysfs_unregister(struct device *dev)
495{
496 /* nothing */
497}
498#endif /* SYSFS */
499
500static struct i2c_driver rs5c372_driver;
501
502static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
503{
504 unsigned char buf[2];
505 int addr, i, ret = 0;
506
507 if (rs5c372->type == rtc_r2025sd) {
508 if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
509 return ret;
510 rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
511 } else {
512 if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
513 return ret;
514 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
515 }
516
517 addr = RS5C_ADDR(RS5C_REG_CTRL1);
518 buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
519 buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
520
521 /* use 24hr mode */
522 switch (rs5c372->type) {
523 case rtc_rs5c372a:
524 case rtc_rs5c372b:
525 buf[1] |= RS5C372_CTRL2_24;
526 rs5c372->time24 = 1;
527 break;
528 case rtc_r2025sd:
529 case rtc_rv5c386:
530 case rtc_rv5c387a:
531 buf[0] |= RV5C387_CTRL1_24;
532 rs5c372->time24 = 1;
533 break;
534 default:
535 /* impossible */
536 break;
537 }
538
539 for (i = 0; i < sizeof(buf); i++) {
540 addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
541 ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
542 if (unlikely(ret < 0))
543 return ret;
544 }
545
546 rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
547 rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
548
549 return 0;
550}
551
552static int rs5c372_probe(struct i2c_client *client,
553 const struct i2c_device_id *id)
554{
555 int err = 0;
556 int smbus_mode = 0;
557 struct rs5c372 *rs5c372;
558 struct rtc_time tm;
559
560 dev_dbg(&client->dev, "%s\n", __func__);
561
562 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
563 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
564 /*
565 * If we don't have any master mode adapter, try breaking
566 * it down in to the barest of capabilities.
567 */
568 if (i2c_check_functionality(client->adapter,
569 I2C_FUNC_SMBUS_BYTE_DATA |
570 I2C_FUNC_SMBUS_I2C_BLOCK))
571 smbus_mode = 1;
572 else {
573 /* Still no good, give up */
574 err = -ENODEV;
575 goto exit;
576 }
577 }
578
579 if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
580 err = -ENOMEM;
581 goto exit;
582 }
583
584 rs5c372->client = client;
585 i2c_set_clientdata(client, rs5c372);
586 rs5c372->type = id->driver_data;
587
588 /* we read registers 0x0f then 0x00-0x0f; skip the first one */
589 rs5c372->regs = &rs5c372->buf[1];
590 rs5c372->smbus = smbus_mode;
591
592 err = rs5c_get_regs(rs5c372);
593 if (err < 0)
594 goto exit_kfree;
595
596 /* clock may be set for am/pm or 24 hr time */
597 switch (rs5c372->type) {
598 case rtc_rs5c372a:
599 case rtc_rs5c372b:
600 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
601 * so does periodic irq, except some 327a modes.
602 */
603 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
604 rs5c372->time24 = 1;
605 break;
606 case rtc_r2025sd:
607 case rtc_rv5c386:
608 case rtc_rv5c387a:
609 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
610 rs5c372->time24 = 1;
611 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
612 * irq, on both 386 and 387
613 */
614 break;
615 default:
616 dev_err(&client->dev, "unknown RTC type\n");
617 goto exit_kfree;
618 }
619
620 /* if the oscillator lost power and no other software (like
621 * the bootloader) set it up, do it here.
622 *
623 * The R2025S/D does this a little differently than the other
624 * parts, so we special case that..
625 */
626 err = rs5c_oscillator_setup(rs5c372);
627 if (unlikely(err < 0)) {
628 dev_err(&client->dev, "setup error\n");
629 goto exit_kfree;
630 }
631
632 if (rs5c372_get_datetime(client, &tm) < 0)
633 dev_warn(&client->dev, "clock needs to be set\n");
634
635 dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
636 ({ char *s; switch (rs5c372->type) {
637 case rtc_r2025sd: s = "r2025sd"; break;
638 case rtc_rs5c372a: s = "rs5c372a"; break;
639 case rtc_rs5c372b: s = "rs5c372b"; break;
640 case rtc_rv5c386: s = "rv5c386"; break;
641 case rtc_rv5c387a: s = "rv5c387a"; break;
642 default: s = "chip"; break;
643 }; s;}),
644 rs5c372->time24 ? "24hr" : "am/pm"
645 );
646
647 /* REVISIT use client->irq to register alarm irq ... */
648
649 rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
650 &client->dev, &rs5c372_rtc_ops, THIS_MODULE);
651
652 if (IS_ERR(rs5c372->rtc)) {
653 err = PTR_ERR(rs5c372->rtc);
654 goto exit_kfree;
655 }
656
657 err = rs5c_sysfs_register(&client->dev);
658 if (err)
659 goto exit_devreg;
660
661 return 0;
662
663exit_devreg:
664 rtc_device_unregister(rs5c372->rtc);
665
666exit_kfree:
667 kfree(rs5c372);
668
669exit:
670 return err;
671}
672
673static int rs5c372_remove(struct i2c_client *client)
674{
675 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
676
677 rtc_device_unregister(rs5c372->rtc);
678 rs5c_sysfs_unregister(&client->dev);
679 kfree(rs5c372);
680 return 0;
681}
682
683static struct i2c_driver rs5c372_driver = {
684 .driver = {
685 .name = "rtc-rs5c372",
686 },
687 .probe = rs5c372_probe,
688 .remove = rs5c372_remove,
689 .id_table = rs5c372_id,
690};
691
692module_i2c_driver(rs5c372_driver);
693
694MODULE_AUTHOR(
695 "Pavel Mironchik <pmironchik@optifacio.net>, "
696 "Alessandro Zummo <a.zummo@towertech.it>, "
697 "Paul Mundt <lethal@linux-sh.org>");
698MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
699MODULE_LICENSE("GPL");
700MODULE_VERSION(DRV_VERSION);
1/*
2 * An I2C driver for Ricoh RS5C372, R2025S/D and RV5C38[67] RTCs
3 *
4 * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net>
5 * Copyright (C) 2006 Tower Technologies
6 * Copyright (C) 2008 Paul Mundt
7 *
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.
11 */
12
13#include <linux/i2c.h>
14#include <linux/rtc.h>
15#include <linux/bcd.h>
16#include <linux/slab.h>
17#include <linux/module.h>
18
19#define DRV_VERSION "0.6"
20
21
22/*
23 * Ricoh has a family of I2C based RTCs, which differ only slightly from
24 * each other. Differences center on pinout (e.g. how many interrupts,
25 * output clock, etc) and how the control registers are used. The '372
26 * is significant only because that's the one this driver first supported.
27 */
28#define RS5C372_REG_SECS 0
29#define RS5C372_REG_MINS 1
30#define RS5C372_REG_HOURS 2
31#define RS5C372_REG_WDAY 3
32#define RS5C372_REG_DAY 4
33#define RS5C372_REG_MONTH 5
34#define RS5C372_REG_YEAR 6
35#define RS5C372_REG_TRIM 7
36# define RS5C372_TRIM_XSL 0x80
37# define RS5C372_TRIM_MASK 0x7F
38
39#define RS5C_REG_ALARM_A_MIN 8 /* or ALARM_W */
40#define RS5C_REG_ALARM_A_HOURS 9
41#define RS5C_REG_ALARM_A_WDAY 10
42
43#define RS5C_REG_ALARM_B_MIN 11 /* or ALARM_D */
44#define RS5C_REG_ALARM_B_HOURS 12
45#define RS5C_REG_ALARM_B_WDAY 13 /* (ALARM_B only) */
46
47#define RS5C_REG_CTRL1 14
48# define RS5C_CTRL1_AALE (1 << 7) /* or WALE */
49# define RS5C_CTRL1_BALE (1 << 6) /* or DALE */
50# define RV5C387_CTRL1_24 (1 << 5)
51# define RS5C372A_CTRL1_SL1 (1 << 5)
52# define RS5C_CTRL1_CT_MASK (7 << 0)
53# define RS5C_CTRL1_CT0 (0 << 0) /* no periodic irq */
54# define RS5C_CTRL1_CT4 (4 << 0) /* 1 Hz level irq */
55#define RS5C_REG_CTRL2 15
56# define RS5C372_CTRL2_24 (1 << 5)
57# define R2025_CTRL2_XST (1 << 5)
58# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */
59# define RS5C_CTRL2_CTFG (1 << 2)
60# define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */
61# define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */
62
63
64/* to read (style 1) or write registers starting at R */
65#define RS5C_ADDR(R) (((R) << 4) | 0)
66
67
68enum rtc_type {
69 rtc_undef = 0,
70 rtc_r2025sd,
71 rtc_r2221tl,
72 rtc_rs5c372a,
73 rtc_rs5c372b,
74 rtc_rv5c386,
75 rtc_rv5c387a,
76};
77
78static const struct i2c_device_id rs5c372_id[] = {
79 { "r2025sd", rtc_r2025sd },
80 { "r2221tl", rtc_r2221tl },
81 { "rs5c372a", rtc_rs5c372a },
82 { "rs5c372b", rtc_rs5c372b },
83 { "rv5c386", rtc_rv5c386 },
84 { "rv5c387a", rtc_rv5c387a },
85 { }
86};
87MODULE_DEVICE_TABLE(i2c, rs5c372_id);
88
89/* REVISIT: this assumes that:
90 * - we're in the 21st century, so it's safe to ignore the century
91 * bit for rv5c38[67] (REG_MONTH bit 7);
92 * - we should use ALARM_A not ALARM_B (may be wrong on some boards)
93 */
94struct rs5c372 {
95 struct i2c_client *client;
96 struct rtc_device *rtc;
97 enum rtc_type type;
98 unsigned time24:1;
99 unsigned has_irq:1;
100 unsigned smbus:1;
101 char buf[17];
102 char *regs;
103};
104
105static int rs5c_get_regs(struct rs5c372 *rs5c)
106{
107 struct i2c_client *client = rs5c->client;
108 struct i2c_msg msgs[] = {
109 {
110 .addr = client->addr,
111 .flags = I2C_M_RD,
112 .len = sizeof(rs5c->buf),
113 .buf = rs5c->buf
114 },
115 };
116
117 /* This implements the third reading method from the datasheet, using
118 * an internal address that's reset after each transaction (by STOP)
119 * to 0x0f ... so we read extra registers, and skip the first one.
120 *
121 * The first method doesn't work with the iop3xx adapter driver, on at
122 * least 80219 chips; this works around that bug.
123 *
124 * The third method on the other hand doesn't work for the SMBus-only
125 * configurations, so we use the the first method there, stripping off
126 * the extra register in the process.
127 */
128 if (rs5c->smbus) {
129 int addr = RS5C_ADDR(RS5C372_REG_SECS);
130 int size = sizeof(rs5c->buf) - 1;
131
132 if (i2c_smbus_read_i2c_block_data(client, addr, size,
133 rs5c->buf + 1) != size) {
134 dev_warn(&client->dev, "can't read registers\n");
135 return -EIO;
136 }
137 } else {
138 if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
139 dev_warn(&client->dev, "can't read registers\n");
140 return -EIO;
141 }
142 }
143
144 dev_dbg(&client->dev,
145 "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
146 "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
147 rs5c->regs[0], rs5c->regs[1], rs5c->regs[2], rs5c->regs[3],
148 rs5c->regs[4], rs5c->regs[5], rs5c->regs[6], rs5c->regs[7],
149 rs5c->regs[8], rs5c->regs[9], rs5c->regs[10], rs5c->regs[11],
150 rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
151
152 return 0;
153}
154
155static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
156{
157 unsigned hour;
158
159 if (rs5c->time24)
160 return bcd2bin(reg & 0x3f);
161
162 hour = bcd2bin(reg & 0x1f);
163 if (hour == 12)
164 hour = 0;
165 if (reg & 0x20)
166 hour += 12;
167 return hour;
168}
169
170static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
171{
172 if (rs5c->time24)
173 return bin2bcd(hour);
174
175 if (hour > 12)
176 return 0x20 | bin2bcd(hour - 12);
177 if (hour == 12)
178 return 0x20 | bin2bcd(12);
179 if (hour == 0)
180 return bin2bcd(12);
181 return bin2bcd(hour);
182}
183
184static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
185{
186 struct rs5c372 *rs5c = i2c_get_clientdata(client);
187 int status = rs5c_get_regs(rs5c);
188
189 if (status < 0)
190 return status;
191
192 tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
193 tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
194 tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
195
196 tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
197 tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
198
199 /* tm->tm_mon is zero-based */
200 tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
201
202 /* year is 1900 + tm->tm_year */
203 tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
204
205 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
206 "mday=%d, mon=%d, year=%d, wday=%d\n",
207 __func__,
208 tm->tm_sec, tm->tm_min, tm->tm_hour,
209 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
210
211 /* rtc might need initialization */
212 return rtc_valid_tm(tm);
213}
214
215static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
216{
217 struct rs5c372 *rs5c = i2c_get_clientdata(client);
218 unsigned char buf[7];
219 int addr;
220
221 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
222 "mday=%d, mon=%d, year=%d, wday=%d\n",
223 __func__,
224 tm->tm_sec, tm->tm_min, tm->tm_hour,
225 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
226
227 addr = RS5C_ADDR(RS5C372_REG_SECS);
228 buf[0] = bin2bcd(tm->tm_sec);
229 buf[1] = bin2bcd(tm->tm_min);
230 buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
231 buf[3] = bin2bcd(tm->tm_wday);
232 buf[4] = bin2bcd(tm->tm_mday);
233 buf[5] = bin2bcd(tm->tm_mon + 1);
234 buf[6] = bin2bcd(tm->tm_year - 100);
235
236 if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
237 dev_err(&client->dev, "%s: write error\n", __func__);
238 return -EIO;
239 }
240
241 return 0;
242}
243
244#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
245#define NEED_TRIM
246#endif
247
248#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
249#define NEED_TRIM
250#endif
251
252#ifdef NEED_TRIM
253static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
254{
255 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
256 u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
257
258 if (osc)
259 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
260
261 if (trim) {
262 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
263 tmp &= RS5C372_TRIM_MASK;
264 if (tmp & 0x3e) {
265 int t = tmp & 0x3f;
266
267 if (tmp & 0x40)
268 t = (~t | (s8)0xc0) + 1;
269 else
270 t = t - 1;
271
272 tmp = t * 2;
273 } else
274 tmp = 0;
275 *trim = tmp;
276 }
277
278 return 0;
279}
280#endif
281
282static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
283{
284 return rs5c372_get_datetime(to_i2c_client(dev), tm);
285}
286
287static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
288{
289 return rs5c372_set_datetime(to_i2c_client(dev), tm);
290}
291
292
293static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
294{
295 struct i2c_client *client = to_i2c_client(dev);
296 struct rs5c372 *rs5c = i2c_get_clientdata(client);
297 unsigned char buf;
298 int status, addr;
299
300 buf = rs5c->regs[RS5C_REG_CTRL1];
301
302 if (!rs5c->has_irq)
303 return -EINVAL;
304
305 status = rs5c_get_regs(rs5c);
306 if (status < 0)
307 return status;
308
309 addr = RS5C_ADDR(RS5C_REG_CTRL1);
310 if (enabled)
311 buf |= RS5C_CTRL1_AALE;
312 else
313 buf &= ~RS5C_CTRL1_AALE;
314
315 if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
316 dev_warn(dev, "can't update alarm\n");
317 status = -EIO;
318 } else
319 rs5c->regs[RS5C_REG_CTRL1] = buf;
320
321 return status;
322}
323
324
325/* NOTE: Since RTC_WKALM_{RD,SET} were originally defined for EFI,
326 * which only exposes a polled programming interface; and since
327 * these calls map directly to those EFI requests; we don't demand
328 * we have an IRQ for this chip when we go through this API.
329 *
330 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
331 * though, managed through RTC_AIE_{ON,OFF} requests.
332 */
333
334static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
335{
336 struct i2c_client *client = to_i2c_client(dev);
337 struct rs5c372 *rs5c = i2c_get_clientdata(client);
338 int status;
339
340 status = rs5c_get_regs(rs5c);
341 if (status < 0)
342 return status;
343
344 /* report alarm time */
345 t->time.tm_sec = 0;
346 t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
347 t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
348 t->time.tm_mday = -1;
349 t->time.tm_mon = -1;
350 t->time.tm_year = -1;
351 t->time.tm_wday = -1;
352 t->time.tm_yday = -1;
353 t->time.tm_isdst = -1;
354
355 /* ... and status */
356 t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
357 t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
358
359 return 0;
360}
361
362static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
363{
364 struct i2c_client *client = to_i2c_client(dev);
365 struct rs5c372 *rs5c = i2c_get_clientdata(client);
366 int status, addr, i;
367 unsigned char buf[3];
368
369 /* only handle up to 24 hours in the future, like RTC_ALM_SET */
370 if (t->time.tm_mday != -1
371 || t->time.tm_mon != -1
372 || t->time.tm_year != -1)
373 return -EINVAL;
374
375 /* REVISIT: round up tm_sec */
376
377 /* if needed, disable irq (clears pending status) */
378 status = rs5c_get_regs(rs5c);
379 if (status < 0)
380 return status;
381 if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
382 addr = RS5C_ADDR(RS5C_REG_CTRL1);
383 buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
384 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
385 dev_dbg(dev, "can't disable alarm\n");
386 return -EIO;
387 }
388 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
389 }
390
391 /* set alarm */
392 buf[0] = bin2bcd(t->time.tm_min);
393 buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
394 buf[2] = 0x7f; /* any/all days */
395
396 for (i = 0; i < sizeof(buf); i++) {
397 addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
398 if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
399 dev_dbg(dev, "can't set alarm time\n");
400 return -EIO;
401 }
402 }
403
404 /* ... and maybe enable its irq */
405 if (t->enabled) {
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 dev_warn(dev, "can't enable alarm\n");
410 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
411 }
412
413 return 0;
414}
415
416#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
417
418static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
419{
420 int err, osc, trim;
421
422 err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
423 if (err == 0) {
424 seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
425 osc / 1000, osc % 1000);
426 seq_printf(seq, "trim\t\t: %d\n", trim);
427 }
428
429 return 0;
430}
431
432#else
433#define rs5c372_rtc_proc NULL
434#endif
435
436static const struct rtc_class_ops rs5c372_rtc_ops = {
437 .proc = rs5c372_rtc_proc,
438 .read_time = rs5c372_rtc_read_time,
439 .set_time = rs5c372_rtc_set_time,
440 .read_alarm = rs5c_read_alarm,
441 .set_alarm = rs5c_set_alarm,
442 .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
443};
444
445#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
446
447static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
448 struct device_attribute *attr, char *buf)
449{
450 int err, trim;
451
452 err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
453 if (err)
454 return err;
455
456 return sprintf(buf, "%d\n", trim);
457}
458static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
459
460static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
461 struct device_attribute *attr, char *buf)
462{
463 int err, osc;
464
465 err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
466 if (err)
467 return err;
468
469 return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
470}
471static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
472
473static int rs5c_sysfs_register(struct device *dev)
474{
475 int err;
476
477 err = device_create_file(dev, &dev_attr_trim);
478 if (err)
479 return err;
480 err = device_create_file(dev, &dev_attr_osc);
481 if (err)
482 device_remove_file(dev, &dev_attr_trim);
483
484 return err;
485}
486
487static void rs5c_sysfs_unregister(struct device *dev)
488{
489 device_remove_file(dev, &dev_attr_trim);
490 device_remove_file(dev, &dev_attr_osc);
491}
492
493#else
494static int rs5c_sysfs_register(struct device *dev)
495{
496 return 0;
497}
498
499static void rs5c_sysfs_unregister(struct device *dev)
500{
501 /* nothing */
502}
503#endif /* SYSFS */
504
505static struct i2c_driver rs5c372_driver;
506
507static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
508{
509 unsigned char buf[2];
510 int addr, i, ret = 0;
511
512 if (rs5c372->type == rtc_r2025sd) {
513 if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
514 return ret;
515 rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
516 } else {
517 if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
518 return ret;
519 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
520 }
521
522 addr = RS5C_ADDR(RS5C_REG_CTRL1);
523 buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
524 buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
525
526 /* use 24hr mode */
527 switch (rs5c372->type) {
528 case rtc_rs5c372a:
529 case rtc_rs5c372b:
530 buf[1] |= RS5C372_CTRL2_24;
531 rs5c372->time24 = 1;
532 break;
533 case rtc_r2025sd:
534 case rtc_r2221tl:
535 case rtc_rv5c386:
536 case rtc_rv5c387a:
537 buf[0] |= RV5C387_CTRL1_24;
538 rs5c372->time24 = 1;
539 break;
540 default:
541 /* impossible */
542 break;
543 }
544
545 for (i = 0; i < sizeof(buf); i++) {
546 addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
547 ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
548 if (unlikely(ret < 0))
549 return ret;
550 }
551
552 rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
553 rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
554
555 return 0;
556}
557
558static int rs5c372_probe(struct i2c_client *client,
559 const struct i2c_device_id *id)
560{
561 int err = 0;
562 int smbus_mode = 0;
563 struct rs5c372 *rs5c372;
564 struct rtc_time tm;
565
566 dev_dbg(&client->dev, "%s\n", __func__);
567
568 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
569 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
570 /*
571 * If we don't have any master mode adapter, try breaking
572 * it down in to the barest of capabilities.
573 */
574 if (i2c_check_functionality(client->adapter,
575 I2C_FUNC_SMBUS_BYTE_DATA |
576 I2C_FUNC_SMBUS_I2C_BLOCK))
577 smbus_mode = 1;
578 else {
579 /* Still no good, give up */
580 err = -ENODEV;
581 goto exit;
582 }
583 }
584
585 rs5c372 = devm_kzalloc(&client->dev, sizeof(struct rs5c372),
586 GFP_KERNEL);
587 if (!rs5c372) {
588 err = -ENOMEM;
589 goto exit;
590 }
591
592 rs5c372->client = client;
593 i2c_set_clientdata(client, rs5c372);
594 rs5c372->type = id->driver_data;
595
596 /* we read registers 0x0f then 0x00-0x0f; skip the first one */
597 rs5c372->regs = &rs5c372->buf[1];
598 rs5c372->smbus = smbus_mode;
599
600 err = rs5c_get_regs(rs5c372);
601 if (err < 0)
602 goto exit;
603
604 /* clock may be set for am/pm or 24 hr time */
605 switch (rs5c372->type) {
606 case rtc_rs5c372a:
607 case rtc_rs5c372b:
608 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
609 * so does periodic irq, except some 327a modes.
610 */
611 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
612 rs5c372->time24 = 1;
613 break;
614 case rtc_r2025sd:
615 case rtc_r2221tl:
616 case rtc_rv5c386:
617 case rtc_rv5c387a:
618 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
619 rs5c372->time24 = 1;
620 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
621 * irq, on both 386 and 387
622 */
623 break;
624 default:
625 dev_err(&client->dev, "unknown RTC type\n");
626 goto exit;
627 }
628
629 /* if the oscillator lost power and no other software (like
630 * the bootloader) set it up, do it here.
631 *
632 * The R2025S/D does this a little differently than the other
633 * parts, so we special case that..
634 */
635 err = rs5c_oscillator_setup(rs5c372);
636 if (unlikely(err < 0)) {
637 dev_err(&client->dev, "setup error\n");
638 goto exit;
639 }
640
641 if (rs5c372_get_datetime(client, &tm) < 0)
642 dev_warn(&client->dev, "clock needs to be set\n");
643
644 dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
645 ({ char *s; switch (rs5c372->type) {
646 case rtc_r2025sd: s = "r2025sd"; break;
647 case rtc_r2221tl: s = "r2221tl"; break;
648 case rtc_rs5c372a: s = "rs5c372a"; break;
649 case rtc_rs5c372b: s = "rs5c372b"; break;
650 case rtc_rv5c386: s = "rv5c386"; break;
651 case rtc_rv5c387a: s = "rv5c387a"; break;
652 default: s = "chip"; break;
653 }; s;}),
654 rs5c372->time24 ? "24hr" : "am/pm"
655 );
656
657 /* REVISIT use client->irq to register alarm irq ... */
658 rs5c372->rtc = devm_rtc_device_register(&client->dev,
659 rs5c372_driver.driver.name,
660 &rs5c372_rtc_ops, THIS_MODULE);
661
662 if (IS_ERR(rs5c372->rtc)) {
663 err = PTR_ERR(rs5c372->rtc);
664 goto exit;
665 }
666
667 err = rs5c_sysfs_register(&client->dev);
668 if (err)
669 goto exit;
670
671 return 0;
672
673exit:
674 return err;
675}
676
677static int rs5c372_remove(struct i2c_client *client)
678{
679 rs5c_sysfs_unregister(&client->dev);
680 return 0;
681}
682
683static struct i2c_driver rs5c372_driver = {
684 .driver = {
685 .name = "rtc-rs5c372",
686 },
687 .probe = rs5c372_probe,
688 .remove = rs5c372_remove,
689 .id_table = rs5c372_id,
690};
691
692module_i2c_driver(rs5c372_driver);
693
694MODULE_AUTHOR(
695 "Pavel Mironchik <pmironchik@optifacio.net>, "
696 "Alessandro Zummo <a.zummo@towertech.it>, "
697 "Paul Mundt <lethal@linux-sh.org>");
698MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
699MODULE_LICENSE("GPL");
700MODULE_VERSION(DRV_VERSION);