2 * Driver for the Epson RTC module RX-8010 SJ
4 * Copyright(C) Timesys Corporation 2015
5 * Copyright(C) General Electric Company 2015
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
13 #include <linux/bcd.h>
14 #include <linux/bitops.h>
15 #include <linux/i2c.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/rtc.h>
20 #define RX8010_SEC 0x10
21 #define RX8010_MIN 0x11
22 #define RX8010_HOUR 0x12
23 #define RX8010_WDAY 0x13
24 #define RX8010_MDAY 0x14
25 #define RX8010_MONTH 0x15
26 #define RX8010_YEAR 0x16
27 #define RX8010_YEAR 0x16
28 #define RX8010_RESV17 0x17
29 #define RX8010_ALMIN 0x18
30 #define RX8010_ALHOUR 0x19
31 #define RX8010_ALWDAY 0x1A
32 #define RX8010_TCOUNT0 0x1B
33 #define RX8010_TCOUNT1 0x1C
34 #define RX8010_EXT 0x1D
35 #define RX8010_FLAG 0x1E
36 #define RX8010_CTRL 0x1F
37 /* 0x20 to 0x2F are user registers */
38 #define RX8010_RESV30 0x30
39 #define RX8010_RESV31 0x32
40 #define RX8010_IRQ 0x32
42 #define RX8010_EXT_WADA BIT(3)
44 #define RX8010_FLAG_VLF BIT(1)
45 #define RX8010_FLAG_AF BIT(3)
46 #define RX8010_FLAG_TF BIT(4)
47 #define RX8010_FLAG_UF BIT(5)
49 #define RX8010_CTRL_AIE BIT(3)
50 #define RX8010_CTRL_UIE BIT(5)
51 #define RX8010_CTRL_STOP BIT(6)
52 #define RX8010_CTRL_TEST BIT(7)
54 #define RX8010_ALARM_AE BIT(7)
56 static const struct i2c_device_id rx8010_id[] = {
60 MODULE_DEVICE_TABLE(i2c, rx8010_id);
63 struct i2c_client *client;
64 struct rtc_device *rtc;
68 static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
70 struct i2c_client *client = dev_id;
71 struct rx8010_data *rx8010 = i2c_get_clientdata(client);
74 mutex_lock(&rx8010->rtc->ops_lock);
76 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
79 mutex_unlock(&rx8010->rtc->ops_lock);
83 if (flagreg & RX8010_FLAG_VLF)
84 dev_warn(&client->dev, "Frequency stop detected\n");
86 if (flagreg & RX8010_FLAG_TF) {
87 flagreg &= ~RX8010_FLAG_TF;
88 rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF);
91 if (flagreg & RX8010_FLAG_AF) {
92 flagreg &= ~RX8010_FLAG_AF;
93 rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF);
96 if (flagreg & RX8010_FLAG_UF) {
97 flagreg &= ~RX8010_FLAG_UF;
98 rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);
101 i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
103 mutex_unlock(&rx8010->rtc->ops_lock);
107 static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
109 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
114 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
118 if (flagreg & RX8010_FLAG_VLF) {
119 dev_warn(dev, "Frequency stop detected\n");
123 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC,
126 return err < 0 ? err : -EIO;
128 dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
129 dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
130 dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);
131 dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);
132 dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1;
133 dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100;
134 dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f);
136 return rtc_valid_tm(dt);
139 static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
141 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
146 if ((dt->tm_year < 100) || (dt->tm_year > 199))
149 /* set STOP bit before changing clock/calendar */
150 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
153 rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP;
154 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
159 date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);
160 date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min);
161 date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour);
162 date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday);
163 date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1);
164 date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);
165 date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday);
167 ret = i2c_smbus_write_i2c_block_data(rx8010->client,
168 RX8010_SEC, 7, date);
172 /* clear STOP bit after changing clock/calendar */
173 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
176 rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP;
177 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
182 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
187 if (flagreg & RX8010_FLAG_VLF)
188 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG,
189 flagreg & ~RX8010_FLAG_VLF);
194 static int rx8010_init_client(struct i2c_client *client)
196 struct rx8010_data *rx8010 = i2c_get_clientdata(client);
198 int need_clear = 0, err = 0;
200 /* Initialize reserved registers as specified in datasheet */
201 err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8);
205 err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00);
209 err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08);
213 err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00);
217 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG,
220 return err < 0 ? err : -EIO;
222 if (ctrl[0] & RX8010_FLAG_VLF)
223 dev_warn(&client->dev, "Frequency stop was detected\n");
225 if (ctrl[0] & RX8010_FLAG_AF) {
226 dev_warn(&client->dev, "Alarm was detected\n");
230 if (ctrl[0] & RX8010_FLAG_TF)
233 if (ctrl[0] & RX8010_FLAG_UF)
237 ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);
238 err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]);
243 rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST);
248 static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t)
250 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
251 struct i2c_client *client = rx8010->client;
256 err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals);
258 return err < 0 ? err : -EIO;
260 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
265 t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
266 t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
268 if (!(alarmvals[2] & RX8010_ALARM_AE))
269 t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f);
271 t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE);
272 t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled;
277 static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
279 struct i2c_client *client = to_i2c_client(dev);
280 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
285 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
290 if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) {
291 rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE);
292 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
299 flagreg &= ~RX8010_FLAG_AF;
300 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
304 alarmvals[0] = bin2bcd(t->time.tm_min);
305 alarmvals[1] = bin2bcd(t->time.tm_hour);
306 alarmvals[2] = bin2bcd(t->time.tm_mday);
308 err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN,
313 extreg = i2c_smbus_read_byte_data(client, RX8010_EXT);
317 extreg |= RX8010_EXT_WADA;
318 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg);
322 if (alarmvals[2] == 0)
323 alarmvals[2] |= RX8010_ALARM_AE;
325 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY,
331 if (rx8010->rtc->uie_rtctimer.enabled)
332 rx8010->ctrlreg |= RX8010_CTRL_UIE;
333 if (rx8010->rtc->aie_timer.enabled)
335 (RX8010_CTRL_AIE | RX8010_CTRL_UIE);
337 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
346 static int rx8010_alarm_irq_enable(struct device *dev,
347 unsigned int enabled)
349 struct i2c_client *client = to_i2c_client(dev);
350 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
355 ctrl = rx8010->ctrlreg;
358 if (rx8010->rtc->uie_rtctimer.enabled)
359 ctrl |= RX8010_CTRL_UIE;
360 if (rx8010->rtc->aie_timer.enabled)
361 ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE);
363 if (!rx8010->rtc->uie_rtctimer.enabled)
364 ctrl &= ~RX8010_CTRL_UIE;
365 if (!rx8010->rtc->aie_timer.enabled)
366 ctrl &= ~RX8010_CTRL_AIE;
369 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
373 flagreg &= ~RX8010_FLAG_AF;
374 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
378 if (ctrl != rx8010->ctrlreg) {
379 rx8010->ctrlreg = ctrl;
380 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
389 static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
391 struct i2c_client *client = to_i2c_client(dev);
392 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
398 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
402 tmp = !!(flagreg & RX8010_FLAG_VLF);
403 if (copy_to_user((void __user *)arg, &tmp, sizeof(int)))
409 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
414 flagreg &= ~RX8010_FLAG_VLF;
415 ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
426 static const struct rtc_class_ops rx8010_rtc_ops_default = {
427 .read_time = rx8010_get_time,
428 .set_time = rx8010_set_time,
429 .ioctl = rx8010_ioctl,
432 static const struct rtc_class_ops rx8010_rtc_ops_alarm = {
433 .read_time = rx8010_get_time,
434 .set_time = rx8010_set_time,
435 .ioctl = rx8010_ioctl,
436 .read_alarm = rx8010_read_alarm,
437 .set_alarm = rx8010_set_alarm,
438 .alarm_irq_enable = rx8010_alarm_irq_enable,
441 static int rx8010_probe(struct i2c_client *client,
442 const struct i2c_device_id *id)
444 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
445 const struct rtc_class_ops *rtc_ops;
446 struct rx8010_data *rx8010;
449 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
450 | I2C_FUNC_SMBUS_I2C_BLOCK)) {
451 dev_err(&adapter->dev, "doesn't support required functionality\n");
455 rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data),
460 rx8010->client = client;
461 i2c_set_clientdata(client, rx8010);
463 err = rx8010_init_client(client);
467 if (client->irq > 0) {
468 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
469 err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
470 rx8010_irq_1_handler,
471 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
475 dev_err(&client->dev, "unable to request IRQ\n");
479 rtc_ops = &rx8010_rtc_ops_alarm;
481 rtc_ops = &rx8010_rtc_ops_default;
484 rx8010->rtc = devm_rtc_device_register(&client->dev, client->name,
485 rtc_ops, THIS_MODULE);
487 if (IS_ERR(rx8010->rtc)) {
488 dev_err(&client->dev, "unable to register the class device\n");
489 return PTR_ERR(rx8010->rtc);
492 rx8010->rtc->max_user_freq = 1;
497 static struct i2c_driver rx8010_driver = {
499 .name = "rtc-rx8010",
501 .probe = rx8010_probe,
502 .id_table = rx8010_id,
505 module_i2c_driver(rx8010_driver);
507 MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>");
508 MODULE_DESCRIPTION("Epson RX8010SJ RTC driver");
509 MODULE_LICENSE("GPL v2");