1 /*
2 * Copyright (c) 2023 Alvaro Garcia Gomez <maxpowel@gmail.com>
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <zephyr/init.h>
8 #include <zephyr/kernel.h>
9 #include <zephyr/sys/byteorder.h>
10 #include <zephyr/sys/util.h>
11
12 #include "rtc_utils.h"
13
14 #include <stdint.h>
15 #include <string.h>
16 #include <zephyr/device.h>
17 #include <zephyr/drivers/gpio.h>
18 #include <zephyr/drivers/i2c.h>
19 #include <zephyr/drivers/rtc.h>
20 #include <zephyr/sys/timeutil.h>
21 #include <zephyr/logging/log.h>
22 LOG_MODULE_REGISTER(pcf8563);
23
24 #define DT_DRV_COMPAT nxp_pcf8563
25
26 #if DT_ANY_INST_HAS_PROP_STATUS_OKAY(int1_gpios) && \
27 (defined(CONFIG_RTC_ALARM) || defined(CONFIG_RTC_UPDATE))
28 /* The user may need only alarms but not interrupts so we will only
29 * include all the interrupt code if the user configured it in the dts
30 */
31 #define PCF8563_INT1_GPIOS_IN_USE 1
32 #endif
33
34 /* The device registers */
35 #define PCF8563_TIME_DATE_REGISTER 0x02
36 #define PCF8563_ALARM_REGISTER 0x09
37 #define PCF8563_CONTROL1_REGISTER 0x00
38 #define PCF8563_CONTROL2_REGISTER 0x01
39 #define PCF8563_CONTROL2_REGISTER_TIE_EN (1 << 0)
40 #define PCF8563_CONTROL2_REGISTER_AIE_EN (1 << 1)
41
42 /* These masks were retrieved from the datasheet
43 * https://www.nxp.com/docs/en/data-sheet/PCF8563.pdf
44 * page 6, section 8.2 Register organization.
45 * Basically, I clean the unused bits and the bits used
46 * for other stuff
47 */
48 #define PCF8563_SECONDS_MASK GENMASK(6, 0)
49 #define PCF8563_MINUTES_MASK GENMASK(6, 0)
50 #define PCF8563_HOURS_MASK GENMASK(5, 0)
51 #define PCF8563_DAYS_MASK GENMASK(5, 0)
52 #define PCF8563_WEEKDAYS_MASK GENMASK(2, 0)
53 #define PCF8563_MONTHS_MASK GENMASK(4, 0)
54
55 /* RTC alarm time fields supported by the PCF8563, page 7 of the datasheet */
56 #define PCF8563_RTC_ALARM_TIME_MASK \
57 (RTC_ALARM_TIME_MASK_MINUTE | RTC_ALARM_TIME_MASK_HOUR | RTC_ALARM_TIME_MASK_MONTHDAY | \
58 RTC_ALARM_TIME_MASK_WEEKDAY)
59
60 #define PCF8563_RTC_TIME_MASK \
61 (RTC_ALARM_TIME_MASK_SECOND | RTC_ALARM_TIME_MASK_MINUTE | RTC_ALARM_TIME_MASK_HOUR | \
62 RTC_ALARM_TIME_MASK_MONTH | RTC_ALARM_TIME_MASK_MONTHDAY | RTC_ALARM_TIME_MASK_YEAR | \
63 RTC_ALARM_TIME_MASK_WEEKDAY)
64
65 struct pcf8563_config {
66 const struct i2c_dt_spec i2c;
67 #ifdef PCF8563_INT1_GPIOS_IN_USE
68 const struct gpio_dt_spec int1;
69 #endif
70 };
71
72
73 #ifdef PCF8563_INT1_GPIOS_IN_USE
74 /* This work will run the user callback function */
75 void callback_work_handler(struct k_work *work);
76 K_WORK_DEFINE(callback_work, callback_work_handler);
77 #endif
78
79 struct pcf8563_data {
80 #ifdef PCF8563_INT1_GPIOS_IN_USE
81 rtc_alarm_callback alarm_callback;
82 void *alarm_user_data;
83 const struct device *dev;
84 struct gpio_callback int1_callback;
85 struct k_work callback_work;
86 #endif
87 };
88
89 /**
90 * The format described below is described in the datasheet
91 * https://www.nxp.com/docs/en/data-sheet/PCF8563.pdf page 10 starting
92 * with 8.4.2 Register Minutes.
93 *
94 * For seconds, first bit is ignored (it is used to check the clock integrity).
95 * The upper digit takes the next 3 bits for the tens place and then the rest
96 * bits for the unit
97 * So for example, value 43 is 40 * 10 + 3, so the tens digit is 4 and unit digit is 3.
98 * Then we put the number 3 in the last 4 bits and the number 4 in next 3 bits
99 * It uses BCD notation so the number 3 is 0011 and the number for is 100 so the final
100 * byte is 0 (ignored bit) 100 (the 4) 0011 (the 3) -> 0100001
101 * Luckily, zephyr provides a couple of functions to do exactlly this: bin2bcd and bcd2bin,
102 * but we will take care about the bits marked as non used in
103 * the datasheet because they may contain unexpected values. Applying a mask will help us
104 * to sanitize the read values
105 */
pcf8563_set_time(const struct device * dev,const struct rtc_time * timeptr)106 int pcf8563_set_time(const struct device *dev, const struct rtc_time *timeptr)
107 {
108 const struct pcf8563_config *config = dev->config;
109 int ret;
110 uint8_t raw_time[7];
111
112 if (!rtc_utils_validate_rtc_time(timeptr, PCF8563_RTC_TIME_MASK)) {
113 LOG_ERR("invalid time");
114 return -EINVAL;
115 }
116
117 /* Set seconds */
118 raw_time[0] = bin2bcd(timeptr->tm_sec);
119
120 /* Set minutes */
121 raw_time[1] = bin2bcd(timeptr->tm_min);
122
123 /* Set hours */
124 raw_time[2] = bin2bcd(timeptr->tm_hour);
125
126 /* Set days */
127 raw_time[3] = bin2bcd(timeptr->tm_mday);
128
129 /* Set weekdays */
130 raw_time[4] = timeptr->tm_wday;
131
132 /*Set month */
133 raw_time[5] = bin2bcd(timeptr->tm_mon);
134
135 /* Set year */
136 raw_time[6] = bin2bcd(timeptr->tm_year);
137
138 /* Write to device */
139 ret = i2c_burst_write_dt(&config->i2c, PCF8563_TIME_DATE_REGISTER,
140 raw_time, sizeof(raw_time));
141 if (ret) {
142 LOG_ERR("Error when setting time: %i", ret);
143 return ret;
144 }
145
146 return 0;
147 }
148
pcf8563_get_time(const struct device * dev,struct rtc_time * timeptr)149 int pcf8563_get_time(const struct device *dev, struct rtc_time *timeptr)
150 {
151 const struct pcf8563_config *config = dev->config;
152 int ret;
153 uint8_t raw_time[7];
154
155 ret = i2c_burst_read_dt(&config->i2c, PCF8563_TIME_DATE_REGISTER,
156 raw_time, sizeof(raw_time));
157 if (ret) {
158 LOG_ERR("Unable to get time. Err: %i", ret);
159 return ret;
160 }
161
162 /* Check integrity, if the first bit is 1 it is ok */
163 if (raw_time[0] & BIT(7)) {
164 LOG_WRN("Clock integrity failed");
165 return -ENODATA;
166 }
167
168 /* Nanoseconds */
169 timeptr->tm_nsec = 0;
170
171 /* Get seconds */
172 timeptr->tm_sec = bcd2bin(raw_time[0] & PCF8563_SECONDS_MASK);
173
174 /* Get minutes */
175 timeptr->tm_min = bcd2bin(raw_time[1] & PCF8563_MINUTES_MASK);
176
177 /* Get hours */
178 timeptr->tm_hour = bcd2bin(raw_time[2] & PCF8563_HOURS_MASK);
179
180 /* Get days */
181 timeptr->tm_mday = bcd2bin(raw_time[3] & PCF8563_DAYS_MASK);
182
183 /* Get weekdays */
184 timeptr->tm_wday = raw_time[4] & PCF8563_WEEKDAYS_MASK;
185
186 /* Get month */
187 timeptr->tm_mon = bcd2bin(raw_time[5] & PCF8563_MONTHS_MASK);
188
189 /* Get year */
190 timeptr->tm_year = bcd2bin(raw_time[6]);
191
192 /* Day number not used */
193 timeptr->tm_yday = -1;
194
195 /* DST not used */
196 timeptr->tm_isdst = -1;
197
198 return 0;
199 }
200
201
202
203 #ifdef CONFIG_RTC_ALARM
204
pcf8563_alarm_get_supported_fields(const struct device * dev,uint16_t id,uint16_t * mask)205 static int pcf8563_alarm_get_supported_fields(const struct device *dev, uint16_t id,
206 uint16_t *mask)
207 {
208 ARG_UNUSED(dev);
209
210 /* This device only has one channel*/
211 if (id != 0) {
212 LOG_ERR("invalid ID %d", id);
213 return -EINVAL;
214 }
215
216 *mask = PCF8563_RTC_ALARM_TIME_MASK;
217
218 return 0;
219 }
220
pcf8563_alarm_set_time(const struct device * dev,uint16_t id,uint16_t mask,const struct rtc_time * timeptr)221 static int pcf8563_alarm_set_time(const struct device *dev, uint16_t id, uint16_t mask,
222 const struct rtc_time *timeptr)
223 {
224 const struct pcf8563_config *config = dev->config;
225 uint8_t regs[4];
226 int ret;
227
228 if (id != 0) {
229 LOG_ERR("invalid ID %d", id);
230 return -EINVAL;
231 }
232
233 if ((mask & ~(PCF8563_RTC_ALARM_TIME_MASK)) != 0) {
234 LOG_ERR("invalid alarm field mask 0x%04x", mask);
235 return -EINVAL;
236 }
237
238 if (!rtc_utils_validate_rtc_time(timeptr, mask)) {
239 LOG_ERR("invalid alarm time");
240 return -EINVAL;
241 }
242
243 /*
244 * The first bit is used as enabled/disabled flag.
245 * The mask will clean it and also the unused bits
246 */
247 if ((mask & RTC_ALARM_TIME_MASK_MINUTE) != 0) {
248 regs[0] = bin2bcd(timeptr->tm_min) & PCF8563_MINUTES_MASK;
249 } else {
250 /* First bit to 1 is alarm disabled */
251 regs[0] = BIT(7);
252 }
253
254 if ((mask & RTC_ALARM_TIME_MASK_HOUR) != 0) {
255 regs[1] = bin2bcd(timeptr->tm_hour) & PCF8563_HOURS_MASK;
256 } else {
257 regs[1] = BIT(7);
258 }
259
260 if ((mask & RTC_ALARM_TIME_MASK_MONTHDAY) != 0) {
261 regs[2] = bin2bcd(timeptr->tm_mday) & PCF8563_DAYS_MASK;
262 } else {
263 regs[2] = BIT(7);
264 }
265
266 if ((mask & RTC_ALARM_TIME_MASK_WEEKDAY) != 0) {
267 regs[3] = bin2bcd(timeptr->tm_wday) & PCF8563_WEEKDAYS_MASK;
268 } else {
269 regs[3] = BIT(7);
270 }
271
272 ret = i2c_burst_write_dt(&config->i2c, PCF8563_ALARM_REGISTER, regs, sizeof(regs));
273 if (ret) {
274 LOG_ERR("Error when setting alarm: %i", ret);
275 return ret;
276 }
277
278 /* Dont forget to enable interrupts */
279 i2c_reg_write_byte_dt(
280 &config->i2c,
281 PCF8563_CONTROL2_REGISTER,
282 PCF8563_CONTROL2_REGISTER_TIE_EN | PCF8563_CONTROL2_REGISTER_AIE_EN
283 );
284
285 return 0;
286 }
287
pcf8563_alarm_get_time(const struct device * dev,uint16_t id,uint16_t * mask,struct rtc_time * timeptr)288 static int pcf8563_alarm_get_time(const struct device *dev, uint16_t id, uint16_t *mask,
289 struct rtc_time *timeptr)
290 {
291 const struct pcf8563_config *config = dev->config;
292 uint8_t regs[4];
293 int err;
294
295 if (id != 0) {
296 LOG_ERR("invalid ID %d", id);
297 return -EINVAL;
298 }
299
300 err = i2c_burst_read_dt(&config->i2c, PCF8563_ALARM_REGISTER, regs, sizeof(regs));
301 if (err) {
302 LOG_ERR("Error when getting alarm time: %i", err);
303 return err;
304 }
305
306 /* Initialize data structure and mask */
307 memset(timeptr, 0U, sizeof(*timeptr));
308 *mask = 0U;
309
310 /* The first bit is the enabled flag */
311 if (regs[0] & BIT(7)) {
312 timeptr->tm_min = bcd2bin(regs[0] & GENMASK(6, 0));
313 *mask |= RTC_ALARM_TIME_MASK_MINUTE;
314 }
315
316 if (regs[1] & BIT(7)) {
317 timeptr->tm_hour = bcd2bin(regs[1] & GENMASK(5, 0));
318 *mask |= RTC_ALARM_TIME_MASK_HOUR;
319 }
320
321 if (regs[2] & BIT(7)) {
322 timeptr->tm_mday = bcd2bin(regs[2] & GENMASK(5, 0));
323 *mask |= RTC_ALARM_TIME_MASK_MONTHDAY;
324 }
325
326 if (regs[3] & BIT(7)) {
327 timeptr->tm_wday = bcd2bin(regs[3] & GENMASK(2, 0));
328 *mask |= RTC_ALARM_TIME_MASK_WEEKDAY;
329 }
330
331 return 0;
332 }
333
pcf8563_alarm_is_pending(const struct device * dev,uint16_t id)334 static int pcf8563_alarm_is_pending(const struct device *dev, uint16_t id)
335 {
336 /* The description of this register is at page 7, section 8.3.2 Register Control_status_2
337 * There are several kinds of alarms, but here we only need to know that anything but 0
338 * means that there was some kind of alarm active
339 */
340 const struct pcf8563_config *config = dev->config;
341 uint8_t reg;
342 int err;
343
344 if (id != 0) {
345 LOG_ERR("invalid ID %d", id);
346 return -EINVAL;
347 }
348
349 err = i2c_reg_read_byte_dt(&config->i2c, PCF8563_CONTROL2_REGISTER, ®);
350 if (err) {
351 LOG_ERR("Error when getting the control register 2: %i", err);
352 return err;
353 }
354
355 /* Only the last bits use useful here */
356 if (reg & GENMASK(3, 2)) {
357 /* Clean the alarm */
358 err = i2c_reg_write_byte_dt(&config->i2c, PCF8563_CONTROL2_REGISTER, GENMASK(1, 0));
359 if (err) {
360 LOG_ERR("Error when clearing alarms: %d", err);
361 return err;
362 }
363 /* There was an alarm */
364 return 1;
365 }
366 /* No alarms */
367 return 0;
368 }
369 #endif
370
371 #ifdef PCF8563_INT1_GPIOS_IN_USE
372 /* The logic related to the pin interrupt logic */
373
callback_work_handler(struct k_work * work)374 void callback_work_handler(struct k_work *work)
375 {
376 /* This function is run as a work so the user can spend here all the necessary time */
377 struct pcf8563_data *data = CONTAINER_OF(work, struct pcf8563_data, callback_work);
378
379 if (data->alarm_callback == NULL) {
380 LOG_WRN("No PCF8563 alarm callback function provided");
381 } else {
382 data->alarm_callback(data->dev, 0, data->alarm_user_data);
383 }
384 }
385
386
387 /* The function called when the clock alarm activates the interrupt*/
gpio_callback_function(const struct device * dev,struct gpio_callback * cb,uint32_t pins)388 void gpio_callback_function(const struct device *dev, struct gpio_callback *cb,
389 uint32_t pins)
390 {
391 struct pcf8563_data *data = CONTAINER_OF(cb, struct pcf8563_data, int1_callback);
392
393 LOG_DBG("PCF8563 interrupt detected");
394 /* By using a work we are able to run "heavier" code */
395 k_work_submit(&(data->callback_work));
396
397 }
398
399 #endif
400
pcf8563_alarm_set_callback(const struct device * dev,uint16_t id,rtc_alarm_callback callback,void * user_data)401 static int pcf8563_alarm_set_callback(const struct device *dev, uint16_t id,
402 rtc_alarm_callback callback, void *user_data)
403 {
404 #ifndef PCF8563_INT1_GPIOS_IN_USE
405 ARG_UNUSED(dev);
406 ARG_UNUSED(id);
407 ARG_UNUSED(callback);
408 ARG_UNUSED(user_data);
409
410 return -ENOTSUP;
411 #else
412 const struct pcf8563_config *config = dev->config;
413 struct pcf8563_data *data = dev->data;
414 int ret;
415
416 if (config->int1.port == NULL) {
417 return -ENOTSUP;
418 }
419
420 if (id != 0) {
421 LOG_ERR("invalid ID %d", id);
422 return -EINVAL;
423 }
424
425 data->alarm_callback = callback;
426 data->alarm_user_data = user_data;
427 data->dev = dev;
428
429 /* The PCF8563 int pin requires a pull up to work */
430 ret = gpio_pin_configure_dt(&config->int1, GPIO_INPUT | GPIO_PULL_UP);
431 if (ret < 0) {
432 LOG_ERR("Error %d: failed to configure %s pin %d",
433 ret, config->int1.port->name, config->int1.pin);
434 return ret;
435 }
436
437 ret = gpio_pin_interrupt_configure_dt(&config->int1, GPIO_INT_EDGE_FALLING);
438 if (ret < 0) {
439 LOG_ERR("Error %d: failed to configure interrupt on %s pin %d",
440 ret, config->int1.port->name, config->int1.pin);
441 return ret;
442 }
443
444
445 gpio_init_callback(&data->int1_callback, gpio_callback_function, BIT(config->int1.pin));
446 gpio_add_callback(config->int1.port, &data->int1_callback);
447 LOG_DBG("Alarm set");
448 return 0;
449 #endif
450 }
451
452 static DEVICE_API(rtc, pcf8563_driver_api) = {
453 .set_time = pcf8563_set_time,
454 .get_time = pcf8563_get_time,
455 #ifdef CONFIG_RTC_ALARM
456 .alarm_get_supported_fields = pcf8563_alarm_get_supported_fields,
457 .alarm_set_time = pcf8563_alarm_set_time,
458 .alarm_get_time = pcf8563_alarm_get_time,
459 .alarm_is_pending = pcf8563_alarm_is_pending,
460 .alarm_set_callback = pcf8563_alarm_set_callback,
461 #endif
462 };
463
464
pcf8563_init(const struct device * dev)465 int pcf8563_init(const struct device *dev)
466 {
467 const struct pcf8563_config *config = dev->config;
468 int ret;
469 uint8_t reg;
470 #ifdef PCF8563_INT1_GPIOS_IN_USE
471 struct pcf8563_data *data = dev->data;
472
473 data->callback_work = callback_work;
474 #endif
475
476 if (!device_is_ready(config->i2c.bus)) {
477 LOG_ERR("Failed to get pointer to %s device!", config->i2c.bus->name);
478 return -ENODEV;
479 }
480
481 /* Check if it's alive. */
482 ret = i2c_reg_read_byte_dt(&config->i2c, PCF8563_CONTROL1_REGISTER, ®);
483 if (ret) {
484 LOG_ERR("Failed to read from PCF85063! (err %i)", ret);
485 return -ENODEV;
486 }
487
488 LOG_INF("%s is initialized!", dev->name);
489
490 return 0;
491 }
492
493 #define PCF8563_INIT(inst) \
494 static const struct pcf8563_config pcf8563_config_##inst = { \
495 .i2c = I2C_DT_SPEC_INST_GET(inst), \
496 IF_ENABLED(PCF8563_INT1_GPIOS_IN_USE, \
497 (.int1 = GPIO_DT_SPEC_INST_GET_OR(inst, int1_gpios, {0}))) \
498 }; \
499 \
500 static struct pcf8563_data pcf8563_data_##inst; \
501 \
502 DEVICE_DT_INST_DEFINE(inst, &pcf8563_init, NULL, \
503 &pcf8563_data_##inst, &pcf8563_config_##inst, POST_KERNEL, \
504 CONFIG_RTC_INIT_PRIORITY, &pcf8563_driver_api);
505
506 DT_INST_FOREACH_STATUS_OKAY(PCF8563_INIT)
507
