fix a kmap leak in virtio_console
[linux/fpc-iii.git] / drivers / rtc / rtc-rx8025.c
blob8fa23eabcb68109d6636b44405cfaf9965aa6be6
1 /*
2 * Driver for Epson's RTC module RX-8025 SA/NB
4 * Copyright (C) 2009 Wolfgang Grandegger <wg@grandegger.com>
6 * Copyright (C) 2005 by Digi International Inc.
7 * All rights reserved.
9 * Modified by fengjh at rising.com.cn
10 * <http://lists.lm-sensors.org/mailman/listinfo/lm-sensors>
11 * 2006.11
13 * Code cleanup by Sergei Poselenov, <sposelenov@emcraft.com>
14 * Converted to new style by Wolfgang Grandegger <wg@grandegger.com>
15 * Alarm and periodic interrupt added by Dmitry Rakhchev <rda@emcraft.com>
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * version 2 as published by the Free Software Foundation.
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/init.h>
25 #include <linux/bcd.h>
26 #include <linux/i2c.h>
27 #include <linux/list.h>
28 #include <linux/rtc.h>
30 /* Register definitions */
31 #define RX8025_REG_SEC 0x00
32 #define RX8025_REG_MIN 0x01
33 #define RX8025_REG_HOUR 0x02
34 #define RX8025_REG_WDAY 0x03
35 #define RX8025_REG_MDAY 0x04
36 #define RX8025_REG_MONTH 0x05
37 #define RX8025_REG_YEAR 0x06
38 #define RX8025_REG_DIGOFF 0x07
39 #define RX8025_REG_ALWMIN 0x08
40 #define RX8025_REG_ALWHOUR 0x09
41 #define RX8025_REG_ALWWDAY 0x0a
42 #define RX8025_REG_ALDMIN 0x0b
43 #define RX8025_REG_ALDHOUR 0x0c
44 /* 0x0d is reserved */
45 #define RX8025_REG_CTRL1 0x0e
46 #define RX8025_REG_CTRL2 0x0f
48 #define RX8025_BIT_CTRL1_CT (7 << 0)
49 /* 1 Hz periodic level irq */
50 #define RX8025_BIT_CTRL1_CT_1HZ 4
51 #define RX8025_BIT_CTRL1_TEST (1 << 3)
52 #define RX8025_BIT_CTRL1_1224 (1 << 5)
53 #define RX8025_BIT_CTRL1_DALE (1 << 6)
54 #define RX8025_BIT_CTRL1_WALE (1 << 7)
56 #define RX8025_BIT_CTRL2_DAFG (1 << 0)
57 #define RX8025_BIT_CTRL2_WAFG (1 << 1)
58 #define RX8025_BIT_CTRL2_CTFG (1 << 2)
59 #define RX8025_BIT_CTRL2_PON (1 << 4)
60 #define RX8025_BIT_CTRL2_XST (1 << 5)
61 #define RX8025_BIT_CTRL2_VDET (1 << 6)
63 /* Clock precision adjustment */
64 #define RX8025_ADJ_RESOLUTION 3050 /* in ppb */
65 #define RX8025_ADJ_DATA_MAX 62
66 #define RX8025_ADJ_DATA_MIN -62
68 static const struct i2c_device_id rx8025_id[] = {
69 { "rx8025", 0 },
70 { }
72 MODULE_DEVICE_TABLE(i2c, rx8025_id);
74 struct rx8025_data {
75 struct i2c_client *client;
76 struct rtc_device *rtc;
77 struct work_struct work;
78 u8 ctrl1;
79 unsigned exiting:1;
82 static int rx8025_read_reg(struct i2c_client *client, int number, u8 *value)
84 int ret = i2c_smbus_read_byte_data(client, (number << 4) | 0x08);
86 if (ret < 0) {
87 dev_err(&client->dev, "Unable to read register #%d\n", number);
88 return ret;
91 *value = ret;
92 return 0;
95 static int rx8025_read_regs(struct i2c_client *client,
96 int number, u8 length, u8 *values)
98 int ret = i2c_smbus_read_i2c_block_data(client, (number << 4) | 0x08,
99 length, values);
101 if (ret != length) {
102 dev_err(&client->dev, "Unable to read registers #%d..#%d\n",
103 number, number + length - 1);
104 return ret < 0 ? ret : -EIO;
107 return 0;
110 static int rx8025_write_reg(struct i2c_client *client, int number, u8 value)
112 int ret = i2c_smbus_write_byte_data(client, number << 4, value);
114 if (ret)
115 dev_err(&client->dev, "Unable to write register #%d\n",
116 number);
118 return ret;
121 static int rx8025_write_regs(struct i2c_client *client,
122 int number, u8 length, u8 *values)
124 int ret = i2c_smbus_write_i2c_block_data(client, (number << 4) | 0x08,
125 length, values);
127 if (ret)
128 dev_err(&client->dev, "Unable to write registers #%d..#%d\n",
129 number, number + length - 1);
131 return ret;
134 static irqreturn_t rx8025_irq(int irq, void *dev_id)
136 struct i2c_client *client = dev_id;
137 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
139 disable_irq_nosync(irq);
140 schedule_work(&rx8025->work);
141 return IRQ_HANDLED;
144 static void rx8025_work(struct work_struct *work)
146 struct rx8025_data *rx8025 = container_of(work, struct rx8025_data,
147 work);
148 struct i2c_client *client = rx8025->client;
149 struct mutex *lock = &rx8025->rtc->ops_lock;
150 u8 status;
152 mutex_lock(lock);
154 if (rx8025_read_reg(client, RX8025_REG_CTRL2, &status))
155 goto out;
157 if (!(status & RX8025_BIT_CTRL2_XST))
158 dev_warn(&client->dev, "Oscillation stop was detected,"
159 "you may have to readjust the clock\n");
161 if (status & RX8025_BIT_CTRL2_CTFG) {
162 /* periodic */
163 status &= ~RX8025_BIT_CTRL2_CTFG;
164 local_irq_disable();
165 rtc_update_irq(rx8025->rtc, 1, RTC_PF | RTC_IRQF);
166 local_irq_enable();
169 if (status & RX8025_BIT_CTRL2_DAFG) {
170 /* alarm */
171 status &= RX8025_BIT_CTRL2_DAFG;
172 if (rx8025_write_reg(client, RX8025_REG_CTRL1,
173 rx8025->ctrl1 & ~RX8025_BIT_CTRL1_DALE))
174 goto out;
175 local_irq_disable();
176 rtc_update_irq(rx8025->rtc, 1, RTC_AF | RTC_IRQF);
177 local_irq_enable();
180 /* acknowledge IRQ */
181 rx8025_write_reg(client, RX8025_REG_CTRL2,
182 status | RX8025_BIT_CTRL2_XST);
184 out:
185 if (!rx8025->exiting)
186 enable_irq(client->irq);
188 mutex_unlock(lock);
191 static int rx8025_get_time(struct device *dev, struct rtc_time *dt)
193 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
194 u8 date[7];
195 int err;
197 err = rx8025_read_regs(rx8025->client, RX8025_REG_SEC, 7, date);
198 if (err)
199 return err;
201 dev_dbg(dev, "%s: read 0x%02x 0x%02x "
202 "0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n", __func__,
203 date[0], date[1], date[2], date[3], date[4],
204 date[5], date[6]);
206 dt->tm_sec = bcd2bin(date[RX8025_REG_SEC] & 0x7f);
207 dt->tm_min = bcd2bin(date[RX8025_REG_MIN] & 0x7f);
208 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
209 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x3f);
210 else
211 dt->tm_hour = bcd2bin(date[RX8025_REG_HOUR] & 0x1f) % 12
212 + (date[RX8025_REG_HOUR] & 0x20 ? 12 : 0);
214 dt->tm_mday = bcd2bin(date[RX8025_REG_MDAY] & 0x3f);
215 dt->tm_mon = bcd2bin(date[RX8025_REG_MONTH] & 0x1f) - 1;
216 dt->tm_year = bcd2bin(date[RX8025_REG_YEAR]);
218 if (dt->tm_year < 70)
219 dt->tm_year += 100;
221 dev_dbg(dev, "%s: date %ds %dm %dh %dmd %dm %dy\n", __func__,
222 dt->tm_sec, dt->tm_min, dt->tm_hour,
223 dt->tm_mday, dt->tm_mon, dt->tm_year);
225 return rtc_valid_tm(dt);
228 static int rx8025_set_time(struct device *dev, struct rtc_time *dt)
230 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
231 u8 date[7];
234 * BUG: The HW assumes every year that is a multiple of 4 to be a leap
235 * year. Next time this is wrong is 2100, which will not be a leap
236 * year.
240 * Here the read-only bits are written as "0". I'm not sure if that
241 * is sound.
243 date[RX8025_REG_SEC] = bin2bcd(dt->tm_sec);
244 date[RX8025_REG_MIN] = bin2bcd(dt->tm_min);
245 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
246 date[RX8025_REG_HOUR] = bin2bcd(dt->tm_hour);
247 else
248 date[RX8025_REG_HOUR] = (dt->tm_hour >= 12 ? 0x20 : 0)
249 | bin2bcd((dt->tm_hour + 11) % 12 + 1);
251 date[RX8025_REG_WDAY] = bin2bcd(dt->tm_wday);
252 date[RX8025_REG_MDAY] = bin2bcd(dt->tm_mday);
253 date[RX8025_REG_MONTH] = bin2bcd(dt->tm_mon + 1);
254 date[RX8025_REG_YEAR] = bin2bcd(dt->tm_year % 100);
256 dev_dbg(dev,
257 "%s: write 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x 0x%02x\n",
258 __func__,
259 date[0], date[1], date[2], date[3], date[4], date[5], date[6]);
261 return rx8025_write_regs(rx8025->client, RX8025_REG_SEC, 7, date);
264 static int rx8025_init_client(struct i2c_client *client, int *need_reset)
266 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
267 u8 ctrl[2], ctrl2;
268 int need_clear = 0;
269 int err;
271 err = rx8025_read_regs(rx8025->client, RX8025_REG_CTRL1, 2, ctrl);
272 if (err)
273 goto out;
275 /* Keep test bit zero ! */
276 rx8025->ctrl1 = ctrl[0] & ~RX8025_BIT_CTRL1_TEST;
278 if (ctrl[1] & RX8025_BIT_CTRL2_PON) {
279 dev_warn(&client->dev, "power-on reset was detected, "
280 "you may have to readjust the clock\n");
281 *need_reset = 1;
284 if (ctrl[1] & RX8025_BIT_CTRL2_VDET) {
285 dev_warn(&client->dev, "a power voltage drop was detected, "
286 "you may have to readjust the clock\n");
287 *need_reset = 1;
290 if (!(ctrl[1] & RX8025_BIT_CTRL2_XST)) {
291 dev_warn(&client->dev, "Oscillation stop was detected,"
292 "you may have to readjust the clock\n");
293 *need_reset = 1;
296 if (ctrl[1] & (RX8025_BIT_CTRL2_DAFG | RX8025_BIT_CTRL2_WAFG)) {
297 dev_warn(&client->dev, "Alarm was detected\n");
298 need_clear = 1;
301 if (!(ctrl[1] & RX8025_BIT_CTRL2_CTFG))
302 need_clear = 1;
304 if (*need_reset || need_clear) {
305 ctrl2 = ctrl[0];
306 ctrl2 &= ~(RX8025_BIT_CTRL2_PON | RX8025_BIT_CTRL2_VDET |
307 RX8025_BIT_CTRL2_CTFG | RX8025_BIT_CTRL2_WAFG |
308 RX8025_BIT_CTRL2_DAFG);
309 ctrl2 |= RX8025_BIT_CTRL2_XST;
311 err = rx8025_write_reg(client, RX8025_REG_CTRL2, ctrl2);
313 out:
314 return err;
317 /* Alarm support */
318 static int rx8025_read_alarm(struct device *dev, struct rtc_wkalrm *t)
320 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
321 struct i2c_client *client = rx8025->client;
322 u8 ctrl2, ald[2];
323 int err;
325 if (client->irq <= 0)
326 return -EINVAL;
328 err = rx8025_read_regs(client, RX8025_REG_ALDMIN, 2, ald);
329 if (err)
330 return err;
332 err = rx8025_read_reg(client, RX8025_REG_CTRL2, &ctrl2);
333 if (err)
334 return err;
336 dev_dbg(dev, "%s: read alarm 0x%02x 0x%02x ctrl2 %02x\n",
337 __func__, ald[0], ald[1], ctrl2);
339 /* Hardware alarms precision is 1 minute! */
340 t->time.tm_sec = 0;
341 t->time.tm_min = bcd2bin(ald[0] & 0x7f);
342 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
343 t->time.tm_hour = bcd2bin(ald[1] & 0x3f);
344 else
345 t->time.tm_hour = bcd2bin(ald[1] & 0x1f) % 12
346 + (ald[1] & 0x20 ? 12 : 0);
348 t->time.tm_wday = -1;
349 t->time.tm_mday = -1;
350 t->time.tm_mon = -1;
351 t->time.tm_year = -1;
353 dev_dbg(dev, "%s: date: %ds %dm %dh %dmd %dm %dy\n",
354 __func__,
355 t->time.tm_sec, t->time.tm_min, t->time.tm_hour,
356 t->time.tm_mday, t->time.tm_mon, t->time.tm_year);
357 t->enabled = !!(rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE);
358 t->pending = (ctrl2 & RX8025_BIT_CTRL2_DAFG) && t->enabled;
360 return err;
363 static int rx8025_set_alarm(struct device *dev, struct rtc_wkalrm *t)
365 struct i2c_client *client = to_i2c_client(dev);
366 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
367 u8 ald[2];
368 int err;
370 if (client->irq <= 0)
371 return -EINVAL;
373 /* Hardware alarm precision is 1 minute! */
374 ald[0] = bin2bcd(t->time.tm_min);
375 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_1224)
376 ald[1] = bin2bcd(t->time.tm_hour);
377 else
378 ald[1] = (t->time.tm_hour >= 12 ? 0x20 : 0)
379 | bin2bcd((t->time.tm_hour + 11) % 12 + 1);
381 dev_dbg(dev, "%s: write 0x%02x 0x%02x\n", __func__, ald[0], ald[1]);
383 if (rx8025->ctrl1 & RX8025_BIT_CTRL1_DALE) {
384 rx8025->ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
385 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
386 rx8025->ctrl1);
387 if (err)
388 return err;
390 err = rx8025_write_regs(rx8025->client, RX8025_REG_ALDMIN, 2, ald);
391 if (err)
392 return err;
394 if (t->enabled) {
395 rx8025->ctrl1 |= RX8025_BIT_CTRL1_DALE;
396 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
397 rx8025->ctrl1);
398 if (err)
399 return err;
402 return 0;
405 static int rx8025_alarm_irq_enable(struct device *dev, unsigned int enabled)
407 struct rx8025_data *rx8025 = dev_get_drvdata(dev);
408 u8 ctrl1;
409 int err;
411 ctrl1 = rx8025->ctrl1;
412 if (enabled)
413 ctrl1 |= RX8025_BIT_CTRL1_DALE;
414 else
415 ctrl1 &= ~RX8025_BIT_CTRL1_DALE;
417 if (ctrl1 != rx8025->ctrl1) {
418 rx8025->ctrl1 = ctrl1;
419 err = rx8025_write_reg(rx8025->client, RX8025_REG_CTRL1,
420 rx8025->ctrl1);
421 if (err)
422 return err;
424 return 0;
427 static struct rtc_class_ops rx8025_rtc_ops = {
428 .read_time = rx8025_get_time,
429 .set_time = rx8025_set_time,
430 .read_alarm = rx8025_read_alarm,
431 .set_alarm = rx8025_set_alarm,
432 .alarm_irq_enable = rx8025_alarm_irq_enable,
436 * Clock precision adjustment support
438 * According to the RX8025 SA/NB application manual the frequency and
439 * temperature characteristics can be approximated using the following
440 * equation:
442 * df = a * (ut - t)**2
444 * df: Frequency deviation in any temperature
445 * a : Coefficient = (-35 +-5) * 10**-9
446 * ut: Ultimate temperature in degree = +25 +-5 degree
447 * t : Any temperature in degree
449 * Note that the clock adjustment in ppb must be entered (which is
450 * the negative value of the deviation).
452 static int rx8025_get_clock_adjust(struct device *dev, int *adj)
454 struct i2c_client *client = to_i2c_client(dev);
455 u8 digoff;
456 int err;
458 err = rx8025_read_reg(client, RX8025_REG_DIGOFF, &digoff);
459 if (err)
460 return err;
462 *adj = digoff >= 64 ? digoff - 128 : digoff;
463 if (*adj > 0)
464 (*adj)--;
465 *adj *= -RX8025_ADJ_RESOLUTION;
467 return 0;
470 static int rx8025_set_clock_adjust(struct device *dev, int adj)
472 struct i2c_client *client = to_i2c_client(dev);
473 u8 digoff;
474 int err;
476 adj /= -RX8025_ADJ_RESOLUTION;
477 if (adj > RX8025_ADJ_DATA_MAX)
478 adj = RX8025_ADJ_DATA_MAX;
479 else if (adj < RX8025_ADJ_DATA_MIN)
480 adj = RX8025_ADJ_DATA_MIN;
481 else if (adj > 0)
482 adj++;
483 else if (adj < 0)
484 adj += 128;
485 digoff = adj;
487 err = rx8025_write_reg(client, RX8025_REG_DIGOFF, digoff);
488 if (err)
489 return err;
491 dev_dbg(dev, "%s: write 0x%02x\n", __func__, digoff);
493 return 0;
496 static ssize_t rx8025_sysfs_show_clock_adjust(struct device *dev,
497 struct device_attribute *attr,
498 char *buf)
500 int err, adj;
502 err = rx8025_get_clock_adjust(dev, &adj);
503 if (err)
504 return err;
506 return sprintf(buf, "%d\n", adj);
509 static ssize_t rx8025_sysfs_store_clock_adjust(struct device *dev,
510 struct device_attribute *attr,
511 const char *buf, size_t count)
513 int adj, err;
515 if (sscanf(buf, "%i", &adj) != 1)
516 return -EINVAL;
518 err = rx8025_set_clock_adjust(dev, adj);
520 return err ? err : count;
523 static DEVICE_ATTR(clock_adjust_ppb, S_IRUGO | S_IWUSR,
524 rx8025_sysfs_show_clock_adjust,
525 rx8025_sysfs_store_clock_adjust);
527 static int rx8025_sysfs_register(struct device *dev)
529 return device_create_file(dev, &dev_attr_clock_adjust_ppb);
532 static void rx8025_sysfs_unregister(struct device *dev)
534 device_remove_file(dev, &dev_attr_clock_adjust_ppb);
537 static int rx8025_probe(struct i2c_client *client,
538 const struct i2c_device_id *id)
540 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
541 struct rx8025_data *rx8025;
542 int err, need_reset = 0;
544 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
545 | I2C_FUNC_SMBUS_I2C_BLOCK)) {
546 dev_err(&adapter->dev,
547 "doesn't support required functionality\n");
548 err = -EIO;
549 goto errout;
552 rx8025 = devm_kzalloc(&client->dev, sizeof(*rx8025), GFP_KERNEL);
553 if (!rx8025) {
554 dev_err(&adapter->dev, "failed to alloc memory\n");
555 err = -ENOMEM;
556 goto errout;
559 rx8025->client = client;
560 i2c_set_clientdata(client, rx8025);
561 INIT_WORK(&rx8025->work, rx8025_work);
563 err = rx8025_init_client(client, &need_reset);
564 if (err)
565 goto errout;
567 if (need_reset) {
568 struct rtc_time tm;
569 dev_info(&client->dev,
570 "bad conditions detected, resetting date\n");
571 rtc_time_to_tm(0, &tm); /* 1970/1/1 */
572 rx8025_set_time(&client->dev, &tm);
575 rx8025->rtc = devm_rtc_device_register(&client->dev, client->name,
576 &rx8025_rtc_ops, THIS_MODULE);
577 if (IS_ERR(rx8025->rtc)) {
578 err = PTR_ERR(rx8025->rtc);
579 dev_err(&client->dev, "unable to register the class device\n");
580 goto errout;
583 if (client->irq > 0) {
584 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
585 err = request_irq(client->irq, rx8025_irq,
586 0, "rx8025", client);
587 if (err) {
588 dev_err(&client->dev, "unable to request IRQ\n");
589 goto errout;
593 rx8025->rtc->irq_freq = 1;
594 rx8025->rtc->max_user_freq = 1;
596 err = rx8025_sysfs_register(&client->dev);
597 if (err)
598 goto errout_irq;
600 return 0;
602 errout_irq:
603 if (client->irq > 0)
604 free_irq(client->irq, client);
606 errout:
607 dev_err(&adapter->dev, "probing for rx8025 failed\n");
608 return err;
611 static int rx8025_remove(struct i2c_client *client)
613 struct rx8025_data *rx8025 = i2c_get_clientdata(client);
614 struct mutex *lock = &rx8025->rtc->ops_lock;
616 if (client->irq > 0) {
617 mutex_lock(lock);
618 rx8025->exiting = 1;
619 mutex_unlock(lock);
621 free_irq(client->irq, client);
622 cancel_work_sync(&rx8025->work);
625 rx8025_sysfs_unregister(&client->dev);
626 return 0;
629 static struct i2c_driver rx8025_driver = {
630 .driver = {
631 .name = "rtc-rx8025",
632 .owner = THIS_MODULE,
634 .probe = rx8025_probe,
635 .remove = rx8025_remove,
636 .id_table = rx8025_id,
639 module_i2c_driver(rx8025_driver);
641 MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
642 MODULE_DESCRIPTION("RX-8025 SA/NB RTC driver");
643 MODULE_LICENSE("GPL");