2 * drivers/rtc/rtc-pcf85363.c
4 * Driver for NXP PCF85363 real-time clock.
6 * Copyright (C) 2017 Eric Nelson
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.
12 * Based loosely on rtc-8583 by Russell King, Wolfram Sang and Juergen Beisert
14 #include <linux/module.h>
15 #include <linux/i2c.h>
16 #include <linux/slab.h>
17 #include <linux/rtc.h>
18 #include <linux/init.h>
19 #include <linux/err.h>
20 #include <linux/errno.h>
21 #include <linux/bcd.h>
23 #include <linux/of_device.h>
24 #include <linux/regmap.h>
29 #define DT_100THS 0x00
31 #define DT_MINUTES 0x02
34 #define DT_WEEKDAYS 0x05
35 #define DT_MONTHS 0x06
41 #define DT_SECOND_ALM1 0x08
42 #define DT_MINUTE_ALM1 0x09
43 #define DT_HOUR_ALM1 0x0a
44 #define DT_DAY_ALM1 0x0b
45 #define DT_MONTH_ALM1 0x0c
46 #define DT_MINUTE_ALM2 0x0d
47 #define DT_HOUR_ALM2 0x0e
48 #define DT_WEEKDAY_ALM2 0x0f
49 #define DT_ALARM_EN 0x10
52 * Time stamp registers
54 #define DT_TIMESTAMP1 0x11
55 #define DT_TIMESTAMP2 0x17
56 #define DT_TIMESTAMP3 0x1d
57 #define DT_TS_MODE 0x23
62 #define CTRL_OFFSET 0x24
63 #define CTRL_OSCILLATOR 0x25
64 #define CTRL_BATTERY 0x26
65 #define CTRL_PIN_IO 0x27
66 #define CTRL_FUNCTION 0x28
67 #define CTRL_INTA_EN 0x29
68 #define CTRL_INTB_EN 0x2a
69 #define CTRL_FLAGS 0x2b
70 #define CTRL_RAMBYTE 0x2c
71 #define CTRL_WDOG 0x2d
72 #define CTRL_STOP_EN 0x2e
73 #define CTRL_RESETS 0x2f
76 #define ALRM_SEC_A1E BIT(0)
77 #define ALRM_MIN_A1E BIT(1)
78 #define ALRM_HR_A1E BIT(2)
79 #define ALRM_DAY_A1E BIT(3)
80 #define ALRM_MON_A1E BIT(4)
81 #define ALRM_MIN_A2E BIT(5)
82 #define ALRM_HR_A2E BIT(6)
83 #define ALRM_DAY_A2E BIT(7)
85 #define INT_WDIE BIT(0)
86 #define INT_BSIE BIT(1)
87 #define INT_TSRIE BIT(2)
88 #define INT_A2IE BIT(3)
89 #define INT_A1IE BIT(4)
90 #define INT_OIE BIT(5)
91 #define INT_PIE BIT(6)
92 #define INT_ILP BIT(7)
94 #define FLAGS_TSR1F BIT(0)
95 #define FLAGS_TSR2F BIT(1)
96 #define FLAGS_TSR3F BIT(2)
97 #define FLAGS_BSF BIT(3)
98 #define FLAGS_WDF BIT(4)
99 #define FLAGS_A1F BIT(5)
100 #define FLAGS_A2F BIT(6)
101 #define FLAGS_PIF BIT(7)
103 #define PIN_IO_INTAPM GENMASK(1, 0)
104 #define PIN_IO_INTA_CLK 0
105 #define PIN_IO_INTA_BAT 1
106 #define PIN_IO_INTA_OUT 2
107 #define PIN_IO_INTA_HIZ 3
109 #define STOP_EN_STOP BIT(0)
111 #define RESET_CPR 0xa4
113 #define NVRAM_SIZE 0x40
115 static struct i2c_driver pcf85363_driver;
119 struct rtc_device *rtc;
120 struct regmap *regmap;
123 static int pcf85363_rtc_read_time(struct device *dev, struct rtc_time *tm)
125 struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
126 unsigned char buf[DT_YEARS + 1];
127 int ret, len = sizeof(buf);
129 /* read the RTC date and time registers all at once */
130 ret = regmap_bulk_read(pcf85363->regmap, DT_100THS, buf, len);
132 dev_err(dev, "%s: error %d\n", __func__, ret);
136 tm->tm_year = bcd2bin(buf[DT_YEARS]);
137 /* adjust for 1900 base of rtc_time */
140 tm->tm_wday = buf[DT_WEEKDAYS] & 7;
141 buf[DT_SECS] &= 0x7F;
142 tm->tm_sec = bcd2bin(buf[DT_SECS]);
143 buf[DT_MINUTES] &= 0x7F;
144 tm->tm_min = bcd2bin(buf[DT_MINUTES]);
145 tm->tm_hour = bcd2bin(buf[DT_HOURS]);
146 tm->tm_mday = bcd2bin(buf[DT_DAYS]);
147 tm->tm_mon = bcd2bin(buf[DT_MONTHS]) - 1;
152 static int pcf85363_rtc_set_time(struct device *dev, struct rtc_time *tm)
154 struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
155 unsigned char tmp[11];
156 unsigned char *buf = &tmp[2];
159 tmp[0] = STOP_EN_STOP;
163 buf[DT_SECS] = bin2bcd(tm->tm_sec);
164 buf[DT_MINUTES] = bin2bcd(tm->tm_min);
165 buf[DT_HOURS] = bin2bcd(tm->tm_hour);
166 buf[DT_DAYS] = bin2bcd(tm->tm_mday);
167 buf[DT_WEEKDAYS] = tm->tm_wday;
168 buf[DT_MONTHS] = bin2bcd(tm->tm_mon + 1);
169 buf[DT_YEARS] = bin2bcd(tm->tm_year % 100);
171 ret = regmap_bulk_write(pcf85363->regmap, CTRL_STOP_EN,
176 return regmap_write(pcf85363->regmap, CTRL_STOP_EN, 0);
179 static int pcf85363_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
181 struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
182 unsigned char buf[DT_MONTH_ALM1 - DT_SECOND_ALM1 + 1];
186 ret = regmap_bulk_read(pcf85363->regmap, DT_SECOND_ALM1, buf,
191 alrm->time.tm_sec = bcd2bin(buf[0]);
192 alrm->time.tm_min = bcd2bin(buf[1]);
193 alrm->time.tm_hour = bcd2bin(buf[2]);
194 alrm->time.tm_mday = bcd2bin(buf[3]);
195 alrm->time.tm_mon = bcd2bin(buf[4]) - 1;
197 ret = regmap_read(pcf85363->regmap, CTRL_INTA_EN, &val);
201 alrm->enabled = !!(val & INT_A1IE);
206 static int _pcf85363_rtc_alarm_irq_enable(struct pcf85363 *pcf85363, unsigned
209 unsigned int alarm_flags = ALRM_SEC_A1E | ALRM_MIN_A1E | ALRM_HR_A1E |
210 ALRM_DAY_A1E | ALRM_MON_A1E;
213 ret = regmap_update_bits(pcf85363->regmap, DT_ALARM_EN, alarm_flags,
214 enabled ? alarm_flags : 0);
218 ret = regmap_update_bits(pcf85363->regmap, CTRL_INTA_EN,
219 INT_A1IE, enabled ? INT_A1IE : 0);
224 /* clear current flags */
225 return regmap_update_bits(pcf85363->regmap, CTRL_FLAGS, FLAGS_A1F, 0);
228 static int pcf85363_rtc_alarm_irq_enable(struct device *dev,
229 unsigned int enabled)
231 struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
233 return _pcf85363_rtc_alarm_irq_enable(pcf85363, enabled);
236 static int pcf85363_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
238 struct pcf85363 *pcf85363 = dev_get_drvdata(dev);
239 unsigned char buf[DT_MONTH_ALM1 - DT_SECOND_ALM1 + 1];
242 buf[0] = bin2bcd(alrm->time.tm_sec);
243 buf[1] = bin2bcd(alrm->time.tm_min);
244 buf[2] = bin2bcd(alrm->time.tm_hour);
245 buf[3] = bin2bcd(alrm->time.tm_mday);
246 buf[4] = bin2bcd(alrm->time.tm_mon + 1);
249 * Disable the alarm interrupt before changing the value to avoid
250 * spurious interrupts
252 ret = _pcf85363_rtc_alarm_irq_enable(pcf85363, 0);
256 ret = regmap_bulk_write(pcf85363->regmap, DT_SECOND_ALM1, buf,
261 return _pcf85363_rtc_alarm_irq_enable(pcf85363, alrm->enabled);
264 static irqreturn_t pcf85363_rtc_handle_irq(int irq, void *dev_id)
266 struct pcf85363 *pcf85363 = i2c_get_clientdata(dev_id);
270 err = regmap_read(pcf85363->regmap, CTRL_FLAGS, &flags);
274 if (flags & FLAGS_A1F) {
275 rtc_update_irq(pcf85363->rtc, 1, RTC_IRQF | RTC_AF);
276 regmap_update_bits(pcf85363->regmap, CTRL_FLAGS, FLAGS_A1F, 0);
283 static const struct rtc_class_ops rtc_ops = {
284 .read_time = pcf85363_rtc_read_time,
285 .set_time = pcf85363_rtc_set_time,
288 static const struct rtc_class_ops rtc_ops_alarm = {
289 .read_time = pcf85363_rtc_read_time,
290 .set_time = pcf85363_rtc_set_time,
291 .read_alarm = pcf85363_rtc_read_alarm,
292 .set_alarm = pcf85363_rtc_set_alarm,
293 .alarm_irq_enable = pcf85363_rtc_alarm_irq_enable,
296 static int pcf85363_nvram_read(void *priv, unsigned int offset, void *val,
299 struct pcf85363 *pcf85363 = priv;
301 return regmap_bulk_read(pcf85363->regmap, CTRL_RAM + offset,
305 static int pcf85363_nvram_write(void *priv, unsigned int offset, void *val,
308 struct pcf85363 *pcf85363 = priv;
310 return regmap_bulk_write(pcf85363->regmap, CTRL_RAM + offset,
314 static const struct regmap_config regmap_config = {
317 .max_register = 0x7f,
320 static int pcf85363_probe(struct i2c_client *client,
321 const struct i2c_device_id *id)
323 struct pcf85363 *pcf85363;
324 struct nvmem_config nvmem_cfg = {
329 .reg_read = pcf85363_nvram_read,
330 .reg_write = pcf85363_nvram_write,
334 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
337 pcf85363 = devm_kzalloc(&client->dev, sizeof(struct pcf85363),
342 pcf85363->regmap = devm_regmap_init_i2c(client, ®map_config);
343 if (IS_ERR(pcf85363->regmap)) {
344 dev_err(&client->dev, "regmap allocation failed\n");
345 return PTR_ERR(pcf85363->regmap);
348 pcf85363->dev = &client->dev;
349 i2c_set_clientdata(client, pcf85363);
351 pcf85363->rtc = devm_rtc_allocate_device(pcf85363->dev);
352 if (IS_ERR(pcf85363->rtc))
353 return PTR_ERR(pcf85363->rtc);
355 pcf85363->rtc->ops = &rtc_ops;
357 if (client->irq > 0) {
358 regmap_write(pcf85363->regmap, CTRL_FLAGS, 0);
359 regmap_update_bits(pcf85363->regmap, CTRL_PIN_IO,
360 PIN_IO_INTA_OUT, PIN_IO_INTAPM);
361 ret = devm_request_threaded_irq(pcf85363->dev, client->irq,
362 NULL, pcf85363_rtc_handle_irq,
363 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
366 dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
368 pcf85363->rtc->ops = &rtc_ops_alarm;
371 ret = rtc_register_device(pcf85363->rtc);
373 nvmem_cfg.priv = pcf85363;
374 rtc_nvmem_register(pcf85363->rtc, &nvmem_cfg);
379 static const struct of_device_id dev_ids[] = {
380 { .compatible = "nxp,pcf85363" },
383 MODULE_DEVICE_TABLE(of, dev_ids);
385 static struct i2c_driver pcf85363_driver = {
388 .of_match_table = of_match_ptr(dev_ids),
390 .probe = pcf85363_probe,
393 module_i2c_driver(pcf85363_driver);
395 MODULE_AUTHOR("Eric Nelson");
396 MODULE_DESCRIPTION("pcf85363 I2C RTC driver");
397 MODULE_LICENSE("GPL");