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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
18#define DRV_VERSION "0.6"
19
20
21/*
22 * Ricoh has a family of I2C based RTCs, which differ only slightly from
23 * each other. Differences center on pinout (e.g. how many interrupts,
24 * output clock, etc) and how the control registers are used. The '372
25 * is significant only because that's the one this driver first supported.
26 */
27#define RS5C372_REG_SECS 0
28#define RS5C372_REG_MINS 1
29#define RS5C372_REG_HOURS 2
30#define RS5C372_REG_WDAY 3
31#define RS5C372_REG_DAY 4
32#define RS5C372_REG_MONTH 5
33#define RS5C372_REG_YEAR 6
34#define RS5C372_REG_TRIM 7
35# define RS5C372_TRIM_XSL 0x80
36# define RS5C372_TRIM_MASK 0x7F
37
38#define RS5C_REG_ALARM_A_MIN 8 /* or ALARM_W */
39#define RS5C_REG_ALARM_A_HOURS 9
40#define RS5C_REG_ALARM_A_WDAY 10
41
42#define RS5C_REG_ALARM_B_MIN 11 /* or ALARM_D */
43#define RS5C_REG_ALARM_B_HOURS 12
44#define RS5C_REG_ALARM_B_WDAY 13 /* (ALARM_B only) */
45
46#define RS5C_REG_CTRL1 14
47# define RS5C_CTRL1_AALE (1 << 7) /* or WALE */
48# define RS5C_CTRL1_BALE (1 << 6) /* or DALE */
49# define RV5C387_CTRL1_24 (1 << 5)
50# define RS5C372A_CTRL1_SL1 (1 << 5)
51# define RS5C_CTRL1_CT_MASK (7 << 0)
52# define RS5C_CTRL1_CT0 (0 << 0) /* no periodic irq */
53# define RS5C_CTRL1_CT4 (4 << 0) /* 1 Hz level irq */
54#define RS5C_REG_CTRL2 15
55# define RS5C372_CTRL2_24 (1 << 5)
56# define R2025_CTRL2_XST (1 << 5)
57# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */
58# define RS5C_CTRL2_CTFG (1 << 2)
59# define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */
60# define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */
61
62
63/* to read (style 1) or write registers starting at R */
64#define RS5C_ADDR(R) (((R) << 4) | 0)
65
66
67enum rtc_type {
68 rtc_undef = 0,
69 rtc_r2025sd,
70 rtc_rs5c372a,
71 rtc_rs5c372b,
72 rtc_rv5c386,
73 rtc_rv5c387a,
74};
75
76static const struct i2c_device_id rs5c372_id[] = {
77 { "r2025sd", rtc_r2025sd },
78 { "rs5c372a", rtc_rs5c372a },
79 { "rs5c372b", rtc_rs5c372b },
80 { "rv5c386", rtc_rv5c386 },
81 { "rv5c387a", rtc_rv5c387a },
82 { }
83};
84MODULE_DEVICE_TABLE(i2c, rs5c372_id);
85
86/* REVISIT: this assumes that:
87 * - we're in the 21st century, so it's safe to ignore the century
88 * bit for rv5c38[67] (REG_MONTH bit 7);
89 * - we should use ALARM_A not ALARM_B (may be wrong on some boards)
90 */
91struct rs5c372 {
92 struct i2c_client *client;
93 struct rtc_device *rtc;
94 enum rtc_type type;
95 unsigned time24:1;
96 unsigned has_irq:1;
97 unsigned smbus:1;
98 char buf[17];
99 char *regs;
100};
101
102static int rs5c_get_regs(struct rs5c372 *rs5c)
103{
104 struct i2c_client *client = rs5c->client;
105 struct i2c_msg msgs[] = {
106 { client->addr, I2C_M_RD, sizeof rs5c->buf, rs5c->buf },
107 };
108
109 /* This implements the third reading method from the datasheet, using
110 * an internal address that's reset after each transaction (by STOP)
111 * to 0x0f ... so we read extra registers, and skip the first one.
112 *
113 * The first method doesn't work with the iop3xx adapter driver, on at
114 * least 80219 chips; this works around that bug.
115 *
116 * The third method on the other hand doesn't work for the SMBus-only
117 * configurations, so we use the the first method there, stripping off
118 * the extra register in the process.
119 */
120 if (rs5c->smbus) {
121 int addr = RS5C_ADDR(RS5C372_REG_SECS);
122 int size = sizeof(rs5c->buf) - 1;
123
124 if (i2c_smbus_read_i2c_block_data(client, addr, size,
125 rs5c->buf + 1) != size) {
126 dev_warn(&client->dev, "can't read registers\n");
127 return -EIO;
128 }
129 } else {
130 if ((i2c_transfer(client->adapter, msgs, 1)) != 1) {
131 dev_warn(&client->dev, "can't read registers\n");
132 return -EIO;
133 }
134 }
135
136 dev_dbg(&client->dev,
137 "%02x %02x %02x (%02x) %02x %02x %02x (%02x), "
138 "%02x %02x %02x, %02x %02x %02x; %02x %02x\n",
139 rs5c->regs[0], rs5c->regs[1], rs5c->regs[2], rs5c->regs[3],
140 rs5c->regs[4], rs5c->regs[5], rs5c->regs[6], rs5c->regs[7],
141 rs5c->regs[8], rs5c->regs[9], rs5c->regs[10], rs5c->regs[11],
142 rs5c->regs[12], rs5c->regs[13], rs5c->regs[14], rs5c->regs[15]);
143
144 return 0;
145}
146
147static unsigned rs5c_reg2hr(struct rs5c372 *rs5c, unsigned reg)
148{
149 unsigned hour;
150
151 if (rs5c->time24)
152 return bcd2bin(reg & 0x3f);
153
154 hour = bcd2bin(reg & 0x1f);
155 if (hour == 12)
156 hour = 0;
157 if (reg & 0x20)
158 hour += 12;
159 return hour;
160}
161
162static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour)
163{
164 if (rs5c->time24)
165 return bin2bcd(hour);
166
167 if (hour > 12)
168 return 0x20 | bin2bcd(hour - 12);
169 if (hour == 12)
170 return 0x20 | bin2bcd(12);
171 if (hour == 0)
172 return bin2bcd(12);
173 return bin2bcd(hour);
174}
175
176static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm)
177{
178 struct rs5c372 *rs5c = i2c_get_clientdata(client);
179 int status = rs5c_get_regs(rs5c);
180
181 if (status < 0)
182 return status;
183
184 tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f);
185 tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f);
186 tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]);
187
188 tm->tm_wday = bcd2bin(rs5c->regs[RS5C372_REG_WDAY] & 0x07);
189 tm->tm_mday = bcd2bin(rs5c->regs[RS5C372_REG_DAY] & 0x3f);
190
191 /* tm->tm_mon is zero-based */
192 tm->tm_mon = bcd2bin(rs5c->regs[RS5C372_REG_MONTH] & 0x1f) - 1;
193
194 /* year is 1900 + tm->tm_year */
195 tm->tm_year = bcd2bin(rs5c->regs[RS5C372_REG_YEAR]) + 100;
196
197 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d, "
198 "mday=%d, mon=%d, year=%d, wday=%d\n",
199 __func__,
200 tm->tm_sec, tm->tm_min, tm->tm_hour,
201 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
202
203 /* rtc might need initialization */
204 return rtc_valid_tm(tm);
205}
206
207static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm)
208{
209 struct rs5c372 *rs5c = i2c_get_clientdata(client);
210 unsigned char buf[7];
211 int addr;
212
213 dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d "
214 "mday=%d, mon=%d, year=%d, wday=%d\n",
215 __func__,
216 tm->tm_sec, tm->tm_min, tm->tm_hour,
217 tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday);
218
219 addr = RS5C_ADDR(RS5C372_REG_SECS);
220 buf[0] = bin2bcd(tm->tm_sec);
221 buf[1] = bin2bcd(tm->tm_min);
222 buf[2] = rs5c_hr2reg(rs5c, tm->tm_hour);
223 buf[3] = bin2bcd(tm->tm_wday);
224 buf[4] = bin2bcd(tm->tm_mday);
225 buf[5] = bin2bcd(tm->tm_mon + 1);
226 buf[6] = bin2bcd(tm->tm_year - 100);
227
228 if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) {
229 dev_err(&client->dev, "%s: write error\n", __func__);
230 return -EIO;
231 }
232
233 return 0;
234}
235
236#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
237#define NEED_TRIM
238#endif
239
240#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
241#define NEED_TRIM
242#endif
243
244#ifdef NEED_TRIM
245static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim)
246{
247 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
248 u8 tmp = rs5c372->regs[RS5C372_REG_TRIM];
249
250 if (osc)
251 *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768;
252
253 if (trim) {
254 dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp);
255 tmp &= RS5C372_TRIM_MASK;
256 if (tmp & 0x3e) {
257 int t = tmp & 0x3f;
258
259 if (tmp & 0x40)
260 t = (~t | (s8)0xc0) + 1;
261 else
262 t = t - 1;
263
264 tmp = t * 2;
265 } else
266 tmp = 0;
267 *trim = tmp;
268 }
269
270 return 0;
271}
272#endif
273
274static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm)
275{
276 return rs5c372_get_datetime(to_i2c_client(dev), tm);
277}
278
279static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm)
280{
281 return rs5c372_set_datetime(to_i2c_client(dev), tm);
282}
283
284
285static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
286{
287 struct i2c_client *client = to_i2c_client(dev);
288 struct rs5c372 *rs5c = i2c_get_clientdata(client);
289 unsigned char buf;
290 int status, addr;
291
292 buf = rs5c->regs[RS5C_REG_CTRL1];
293
294 if (!rs5c->has_irq)
295 return -EINVAL;
296
297 status = rs5c_get_regs(rs5c);
298 if (status < 0)
299 return status;
300
301 addr = RS5C_ADDR(RS5C_REG_CTRL1);
302 if (enabled)
303 buf |= RS5C_CTRL1_AALE;
304 else
305 buf &= ~RS5C_CTRL1_AALE;
306
307 if (i2c_smbus_write_byte_data(client, addr, buf) < 0) {
308 printk(KERN_WARNING "%s: can't update alarm\n",
309 rs5c->rtc->name);
310 status = -EIO;
311 } else
312 rs5c->regs[RS5C_REG_CTRL1] = buf;
313
314 return status;
315}
316
317
318/* NOTE: Since RTC_WKALM_{RD,SET} were originally defined for EFI,
319 * which only exposes a polled programming interface; and since
320 * these calls map directly to those EFI requests; we don't demand
321 * we have an IRQ for this chip when we go through this API.
322 *
323 * The older x86_pc derived RTC_ALM_{READ,SET} calls require irqs
324 * though, managed through RTC_AIE_{ON,OFF} requests.
325 */
326
327static int rs5c_read_alarm(struct device *dev, struct rtc_wkalrm *t)
328{
329 struct i2c_client *client = to_i2c_client(dev);
330 struct rs5c372 *rs5c = i2c_get_clientdata(client);
331 int status;
332
333 status = rs5c_get_regs(rs5c);
334 if (status < 0)
335 return status;
336
337 /* report alarm time */
338 t->time.tm_sec = 0;
339 t->time.tm_min = bcd2bin(rs5c->regs[RS5C_REG_ALARM_A_MIN] & 0x7f);
340 t->time.tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C_REG_ALARM_A_HOURS]);
341 t->time.tm_mday = -1;
342 t->time.tm_mon = -1;
343 t->time.tm_year = -1;
344 t->time.tm_wday = -1;
345 t->time.tm_yday = -1;
346 t->time.tm_isdst = -1;
347
348 /* ... and status */
349 t->enabled = !!(rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE);
350 t->pending = !!(rs5c->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_AAFG);
351
352 return 0;
353}
354
355static int rs5c_set_alarm(struct device *dev, struct rtc_wkalrm *t)
356{
357 struct i2c_client *client = to_i2c_client(dev);
358 struct rs5c372 *rs5c = i2c_get_clientdata(client);
359 int status, addr, i;
360 unsigned char buf[3];
361
362 /* only handle up to 24 hours in the future, like RTC_ALM_SET */
363 if (t->time.tm_mday != -1
364 || t->time.tm_mon != -1
365 || t->time.tm_year != -1)
366 return -EINVAL;
367
368 /* REVISIT: round up tm_sec */
369
370 /* if needed, disable irq (clears pending status) */
371 status = rs5c_get_regs(rs5c);
372 if (status < 0)
373 return status;
374 if (rs5c->regs[RS5C_REG_CTRL1] & RS5C_CTRL1_AALE) {
375 addr = RS5C_ADDR(RS5C_REG_CTRL1);
376 buf[0] = rs5c->regs[RS5C_REG_CTRL1] & ~RS5C_CTRL1_AALE;
377 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0) {
378 pr_debug("%s: can't disable alarm\n", rs5c->rtc->name);
379 return -EIO;
380 }
381 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
382 }
383
384 /* set alarm */
385 buf[0] = bin2bcd(t->time.tm_min);
386 buf[1] = rs5c_hr2reg(rs5c, t->time.tm_hour);
387 buf[2] = 0x7f; /* any/all days */
388
389 for (i = 0; i < sizeof(buf); i++) {
390 addr = RS5C_ADDR(RS5C_REG_ALARM_A_MIN + i);
391 if (i2c_smbus_write_byte_data(client, addr, buf[i]) < 0) {
392 pr_debug("%s: can't set alarm time\n", rs5c->rtc->name);
393 return -EIO;
394 }
395 }
396
397 /* ... and maybe enable its irq */
398 if (t->enabled) {
399 addr = RS5C_ADDR(RS5C_REG_CTRL1);
400 buf[0] = rs5c->regs[RS5C_REG_CTRL1] | RS5C_CTRL1_AALE;
401 if (i2c_smbus_write_byte_data(client, addr, buf[0]) < 0)
402 printk(KERN_WARNING "%s: can't enable alarm\n",
403 rs5c->rtc->name);
404 rs5c->regs[RS5C_REG_CTRL1] = buf[0];
405 }
406
407 return 0;
408}
409
410#if defined(CONFIG_RTC_INTF_PROC) || defined(CONFIG_RTC_INTF_PROC_MODULE)
411
412static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq)
413{
414 int err, osc, trim;
415
416 err = rs5c372_get_trim(to_i2c_client(dev), &osc, &trim);
417 if (err == 0) {
418 seq_printf(seq, "crystal\t\t: %d.%03d KHz\n",
419 osc / 1000, osc % 1000);
420 seq_printf(seq, "trim\t\t: %d\n", trim);
421 }
422
423 return 0;
424}
425
426#else
427#define rs5c372_rtc_proc NULL
428#endif
429
430static const struct rtc_class_ops rs5c372_rtc_ops = {
431 .proc = rs5c372_rtc_proc,
432 .read_time = rs5c372_rtc_read_time,
433 .set_time = rs5c372_rtc_set_time,
434 .read_alarm = rs5c_read_alarm,
435 .set_alarm = rs5c_set_alarm,
436 .alarm_irq_enable = rs5c_rtc_alarm_irq_enable,
437};
438
439#if defined(CONFIG_RTC_INTF_SYSFS) || defined(CONFIG_RTC_INTF_SYSFS_MODULE)
440
441static ssize_t rs5c372_sysfs_show_trim(struct device *dev,
442 struct device_attribute *attr, char *buf)
443{
444 int err, trim;
445
446 err = rs5c372_get_trim(to_i2c_client(dev), NULL, &trim);
447 if (err)
448 return err;
449
450 return sprintf(buf, "%d\n", trim);
451}
452static DEVICE_ATTR(trim, S_IRUGO, rs5c372_sysfs_show_trim, NULL);
453
454static ssize_t rs5c372_sysfs_show_osc(struct device *dev,
455 struct device_attribute *attr, char *buf)
456{
457 int err, osc;
458
459 err = rs5c372_get_trim(to_i2c_client(dev), &osc, NULL);
460 if (err)
461 return err;
462
463 return sprintf(buf, "%d.%03d KHz\n", osc / 1000, osc % 1000);
464}
465static DEVICE_ATTR(osc, S_IRUGO, rs5c372_sysfs_show_osc, NULL);
466
467static int rs5c_sysfs_register(struct device *dev)
468{
469 int err;
470
471 err = device_create_file(dev, &dev_attr_trim);
472 if (err)
473 return err;
474 err = device_create_file(dev, &dev_attr_osc);
475 if (err)
476 device_remove_file(dev, &dev_attr_trim);
477
478 return err;
479}
480
481static void rs5c_sysfs_unregister(struct device *dev)
482{
483 device_remove_file(dev, &dev_attr_trim);
484 device_remove_file(dev, &dev_attr_osc);
485}
486
487#else
488static int rs5c_sysfs_register(struct device *dev)
489{
490 return 0;
491}
492
493static void rs5c_sysfs_unregister(struct device *dev)
494{
495 /* nothing */
496}
497#endif /* SYSFS */
498
499static struct i2c_driver rs5c372_driver;
500
501static int rs5c_oscillator_setup(struct rs5c372 *rs5c372)
502{
503 unsigned char buf[2];
504 int addr, i, ret = 0;
505
506 if (rs5c372->type == rtc_r2025sd) {
507 if (!(rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST))
508 return ret;
509 rs5c372->regs[RS5C_REG_CTRL2] &= ~R2025_CTRL2_XST;
510 } else {
511 if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP))
512 return ret;
513 rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP;
514 }
515
516 addr = RS5C_ADDR(RS5C_REG_CTRL1);
517 buf[0] = rs5c372->regs[RS5C_REG_CTRL1];
518 buf[1] = rs5c372->regs[RS5C_REG_CTRL2];
519
520 /* use 24hr mode */
521 switch (rs5c372->type) {
522 case rtc_rs5c372a:
523 case rtc_rs5c372b:
524 buf[1] |= RS5C372_CTRL2_24;
525 rs5c372->time24 = 1;
526 break;
527 case rtc_r2025sd:
528 case rtc_rv5c386:
529 case rtc_rv5c387a:
530 buf[0] |= RV5C387_CTRL1_24;
531 rs5c372->time24 = 1;
532 break;
533 default:
534 /* impossible */
535 break;
536 }
537
538 for (i = 0; i < sizeof(buf); i++) {
539 addr = RS5C_ADDR(RS5C_REG_CTRL1 + i);
540 ret = i2c_smbus_write_byte_data(rs5c372->client, addr, buf[i]);
541 if (unlikely(ret < 0))
542 return ret;
543 }
544
545 rs5c372->regs[RS5C_REG_CTRL1] = buf[0];
546 rs5c372->regs[RS5C_REG_CTRL2] = buf[1];
547
548 return 0;
549}
550
551static int rs5c372_probe(struct i2c_client *client,
552 const struct i2c_device_id *id)
553{
554 int err = 0;
555 int smbus_mode = 0;
556 struct rs5c372 *rs5c372;
557 struct rtc_time tm;
558
559 dev_dbg(&client->dev, "%s\n", __func__);
560
561 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
562 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK)) {
563 /*
564 * If we don't have any master mode adapter, try breaking
565 * it down in to the barest of capabilities.
566 */
567 if (i2c_check_functionality(client->adapter,
568 I2C_FUNC_SMBUS_BYTE_DATA |
569 I2C_FUNC_SMBUS_I2C_BLOCK))
570 smbus_mode = 1;
571 else {
572 /* Still no good, give up */
573 err = -ENODEV;
574 goto exit;
575 }
576 }
577
578 if (!(rs5c372 = kzalloc(sizeof(struct rs5c372), GFP_KERNEL))) {
579 err = -ENOMEM;
580 goto exit;
581 }
582
583 rs5c372->client = client;
584 i2c_set_clientdata(client, rs5c372);
585 rs5c372->type = id->driver_data;
586
587 /* we read registers 0x0f then 0x00-0x0f; skip the first one */
588 rs5c372->regs = &rs5c372->buf[1];
589 rs5c372->smbus = smbus_mode;
590
591 err = rs5c_get_regs(rs5c372);
592 if (err < 0)
593 goto exit_kfree;
594
595 /* clock may be set for am/pm or 24 hr time */
596 switch (rs5c372->type) {
597 case rtc_rs5c372a:
598 case rtc_rs5c372b:
599 /* alarm uses ALARM_A; and nINTRA on 372a, nINTR on 372b.
600 * so does periodic irq, except some 327a modes.
601 */
602 if (rs5c372->regs[RS5C_REG_CTRL2] & RS5C372_CTRL2_24)
603 rs5c372->time24 = 1;
604 break;
605 case rtc_r2025sd:
606 case rtc_rv5c386:
607 case rtc_rv5c387a:
608 if (rs5c372->regs[RS5C_REG_CTRL1] & RV5C387_CTRL1_24)
609 rs5c372->time24 = 1;
610 /* alarm uses ALARM_W; and nINTRB for alarm and periodic
611 * irq, on both 386 and 387
612 */
613 break;
614 default:
615 dev_err(&client->dev, "unknown RTC type\n");
616 goto exit_kfree;
617 }
618
619 /* if the oscillator lost power and no other software (like
620 * the bootloader) set it up, do it here.
621 *
622 * The R2025S/D does this a little differently than the other
623 * parts, so we special case that..
624 */
625 err = rs5c_oscillator_setup(rs5c372);
626 if (unlikely(err < 0)) {
627 dev_err(&client->dev, "setup error\n");
628 goto exit_kfree;
629 }
630
631 if (rs5c372_get_datetime(client, &tm) < 0)
632 dev_warn(&client->dev, "clock needs to be set\n");
633
634 dev_info(&client->dev, "%s found, %s, driver version " DRV_VERSION "\n",
635 ({ char *s; switch (rs5c372->type) {
636 case rtc_r2025sd: s = "r2025sd"; break;
637 case rtc_rs5c372a: s = "rs5c372a"; break;
638 case rtc_rs5c372b: s = "rs5c372b"; break;
639 case rtc_rv5c386: s = "rv5c386"; break;
640 case rtc_rv5c387a: s = "rv5c387a"; break;
641 default: s = "chip"; break;
642 }; s;}),
643 rs5c372->time24 ? "24hr" : "am/pm"
644 );
645
646 /* REVISIT use client->irq to register alarm irq ... */
647
648 rs5c372->rtc = rtc_device_register(rs5c372_driver.driver.name,
649 &client->dev, &rs5c372_rtc_ops, THIS_MODULE);
650
651 if (IS_ERR(rs5c372->rtc)) {
652 err = PTR_ERR(rs5c372->rtc);
653 goto exit_kfree;
654 }
655
656 err = rs5c_sysfs_register(&client->dev);
657 if (err)
658 goto exit_devreg;
659
660 return 0;
661
662exit_devreg:
663 rtc_device_unregister(rs5c372->rtc);
664
665exit_kfree:
666 kfree(rs5c372);
667
668exit:
669 return err;
670}
671
672static int rs5c372_remove(struct i2c_client *client)
673{
674 struct rs5c372 *rs5c372 = i2c_get_clientdata(client);
675
676 rtc_device_unregister(rs5c372->rtc);
677 rs5c_sysfs_unregister(&client->dev);
678 kfree(rs5c372);
679 return 0;
680}
681
682static struct i2c_driver rs5c372_driver = {
683 .driver = {
684 .name = "rtc-rs5c372",
685 },
686 .probe = rs5c372_probe,
687 .remove = rs5c372_remove,
688 .id_table = rs5c372_id,
689};
690
691static __init int rs5c372_init(void)
692{
693 return i2c_add_driver(&rs5c372_driver);
694}
695
696static __exit void rs5c372_exit(void)
697{
698 i2c_del_driver(&rs5c372_driver);
699}
700
701module_init(rs5c372_init);
702module_exit(rs5c372_exit);
703
704MODULE_AUTHOR(
705 "Pavel Mironchik <pmironchik@optifacio.net>, "
706 "Alessandro Zummo <a.zummo@towertech.it>, "
707 "Paul Mundt <lethal@linux-sh.org>");
708MODULE_DESCRIPTION("Ricoh RS5C372 RTC driver");
709MODULE_LICENSE("GPL");
710MODULE_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_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);