1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Real time clock device driver for DA9063
4 * Copyright (C) 2013-2015 Dialog Semiconductor Ltd.
5 */
6
7 #include <linux/delay.h>
8 #include <linux/init.h>
9 #include <linux/interrupt.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/of.h>
13 #include <linux/platform_device.h>
14 #include <linux/regmap.h>
15 #include <linux/rtc.h>
16 #include <linux/slab.h>
17
18 #include <linux/mfd/da9062/registers.h>
19 #include <linux/mfd/da9063/registers.h>
20 #include <linux/mfd/da9063/core.h>
21
22 #define YEARS_TO_DA9063(year) ((year) - 100)
23 #define MONTHS_TO_DA9063(month) ((month) + 1)
24 #define YEARS_FROM_DA9063(year) ((year) + 100)
25 #define MONTHS_FROM_DA9063(month) ((month) - 1)
26
27 enum {
28 RTC_SEC = 0,
29 RTC_MIN = 1,
30 RTC_HOUR = 2,
31 RTC_DAY = 3,
32 RTC_MONTH = 4,
33 RTC_YEAR = 5,
34 RTC_DATA_LEN
35 };
36
37 struct da9063_compatible_rtc_regmap {
38 /* REGS */
39 int rtc_enable_reg;
40 int rtc_enable_32k_crystal_reg;
41 int rtc_alarm_secs_reg;
42 int rtc_alarm_year_reg;
43 int rtc_count_secs_reg;
44 int rtc_count_year_reg;
45 int rtc_event_reg;
46 /* MASKS */
47 int rtc_enable_mask;
48 int rtc_crystal_mask;
49 int rtc_event_alarm_mask;
50 int rtc_alarm_on_mask;
51 int rtc_alarm_status_mask;
52 int rtc_tick_on_mask;
53 int rtc_ready_to_read_mask;
54 int rtc_count_sec_mask;
55 int rtc_count_min_mask;
56 int rtc_count_hour_mask;
57 int rtc_count_day_mask;
58 int rtc_count_month_mask;
59 int rtc_count_year_mask;
60 /* ALARM CONFIG */
61 int rtc_data_start;
62 int rtc_alarm_len;
63 };
64
65 struct da9063_compatible_rtc {
66 struct rtc_device *rtc_dev;
67 struct rtc_time alarm_time;
68 struct regmap *regmap;
69 const struct da9063_compatible_rtc_regmap *config;
70 bool rtc_sync;
71 };
72
73 static const struct da9063_compatible_rtc_regmap da9063_ad_regs = {
74 /* REGS */
75 .rtc_enable_reg = DA9063_REG_CONTROL_E,
76 .rtc_alarm_secs_reg = DA9063_AD_REG_ALARM_MI,
77 .rtc_alarm_year_reg = DA9063_AD_REG_ALARM_Y,
78 .rtc_count_secs_reg = DA9063_REG_COUNT_S,
79 .rtc_count_year_reg = DA9063_REG_COUNT_Y,
80 .rtc_event_reg = DA9063_REG_EVENT_A,
81 /* MASKS */
82 .rtc_enable_mask = DA9063_RTC_EN,
83 .rtc_crystal_mask = DA9063_CRYSTAL,
84 .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
85 .rtc_event_alarm_mask = DA9063_E_ALARM,
86 .rtc_alarm_on_mask = DA9063_ALARM_ON,
87 .rtc_alarm_status_mask = DA9063_ALARM_STATUS_ALARM |
88 DA9063_ALARM_STATUS_TICK,
89 .rtc_tick_on_mask = DA9063_TICK_ON,
90 .rtc_ready_to_read_mask = DA9063_RTC_READ,
91 .rtc_count_sec_mask = DA9063_COUNT_SEC_MASK,
92 .rtc_count_min_mask = DA9063_COUNT_MIN_MASK,
93 .rtc_count_hour_mask = DA9063_COUNT_HOUR_MASK,
94 .rtc_count_day_mask = DA9063_COUNT_DAY_MASK,
95 .rtc_count_month_mask = DA9063_COUNT_MONTH_MASK,
96 .rtc_count_year_mask = DA9063_COUNT_YEAR_MASK,
97 /* ALARM CONFIG */
98 .rtc_data_start = RTC_MIN,
99 .rtc_alarm_len = RTC_DATA_LEN - 1,
100 };
101
102 static const struct da9063_compatible_rtc_regmap da9063_bb_regs = {
103 /* REGS */
104 .rtc_enable_reg = DA9063_REG_CONTROL_E,
105 .rtc_alarm_secs_reg = DA9063_BB_REG_ALARM_S,
106 .rtc_alarm_year_reg = DA9063_BB_REG_ALARM_Y,
107 .rtc_count_secs_reg = DA9063_REG_COUNT_S,
108 .rtc_count_year_reg = DA9063_REG_COUNT_Y,
109 .rtc_event_reg = DA9063_REG_EVENT_A,
110 /* MASKS */
111 .rtc_enable_mask = DA9063_RTC_EN,
112 .rtc_crystal_mask = DA9063_CRYSTAL,
113 .rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
114 .rtc_event_alarm_mask = DA9063_E_ALARM,
115 .rtc_alarm_on_mask = DA9063_ALARM_ON,
116 .rtc_alarm_status_mask = DA9063_ALARM_STATUS_ALARM |
117 DA9063_ALARM_STATUS_TICK,
118 .rtc_tick_on_mask = DA9063_TICK_ON,
119 .rtc_ready_to_read_mask = DA9063_RTC_READ,
120 .rtc_count_sec_mask = DA9063_COUNT_SEC_MASK,
121 .rtc_count_min_mask = DA9063_COUNT_MIN_MASK,
122 .rtc_count_hour_mask = DA9063_COUNT_HOUR_MASK,
123 .rtc_count_day_mask = DA9063_COUNT_DAY_MASK,
124 .rtc_count_month_mask = DA9063_COUNT_MONTH_MASK,
125 .rtc_count_year_mask = DA9063_COUNT_YEAR_MASK,
126 /* ALARM CONFIG */
127 .rtc_data_start = RTC_SEC,
128 .rtc_alarm_len = RTC_DATA_LEN,
129 };
130
131 static const struct da9063_compatible_rtc_regmap da9062_aa_regs = {
132 /* REGS */
133 .rtc_enable_reg = DA9062AA_CONTROL_E,
134 .rtc_alarm_secs_reg = DA9062AA_ALARM_S,
135 .rtc_alarm_year_reg = DA9062AA_ALARM_Y,
136 .rtc_count_secs_reg = DA9062AA_COUNT_S,
137 .rtc_count_year_reg = DA9062AA_COUNT_Y,
138 .rtc_event_reg = DA9062AA_EVENT_A,
139 /* MASKS */
140 .rtc_enable_mask = DA9062AA_RTC_EN_MASK,
141 .rtc_crystal_mask = DA9062AA_CRYSTAL_MASK,
142 .rtc_enable_32k_crystal_reg = DA9062AA_EN_32K,
143 .rtc_event_alarm_mask = DA9062AA_M_ALARM_MASK,
144 .rtc_alarm_on_mask = DA9062AA_ALARM_ON_MASK,
145 .rtc_alarm_status_mask = (0x02 << 6),
146 .rtc_tick_on_mask = DA9062AA_TICK_ON_MASK,
147 .rtc_ready_to_read_mask = DA9062AA_RTC_READ_MASK,
148 .rtc_count_sec_mask = DA9062AA_COUNT_SEC_MASK,
149 .rtc_count_min_mask = DA9062AA_COUNT_MIN_MASK,
150 .rtc_count_hour_mask = DA9062AA_COUNT_HOUR_MASK,
151 .rtc_count_day_mask = DA9062AA_COUNT_DAY_MASK,
152 .rtc_count_month_mask = DA9062AA_COUNT_MONTH_MASK,
153 .rtc_count_year_mask = DA9062AA_COUNT_YEAR_MASK,
154 /* ALARM CONFIG */
155 .rtc_data_start = RTC_SEC,
156 .rtc_alarm_len = RTC_DATA_LEN,
157 };
158
159 static const struct of_device_id da9063_compatible_reg_id_table[] = {
160 { .compatible = "dlg,da9063-rtc", .data = &da9063_bb_regs },
161 { .compatible = "dlg,da9062-rtc", .data = &da9062_aa_regs },
162 { },
163 };
164 MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);
165
da9063_data_to_tm(u8 * data,struct rtc_time * tm,struct da9063_compatible_rtc * rtc)166 static void da9063_data_to_tm(u8 *data, struct rtc_time *tm,
167 struct da9063_compatible_rtc *rtc)
168 {
169 const struct da9063_compatible_rtc_regmap *config = rtc->config;
170
171 tm->tm_sec = data[RTC_SEC] & config->rtc_count_sec_mask;
172 tm->tm_min = data[RTC_MIN] & config->rtc_count_min_mask;
173 tm->tm_hour = data[RTC_HOUR] & config->rtc_count_hour_mask;
174 tm->tm_mday = data[RTC_DAY] & config->rtc_count_day_mask;
175 tm->tm_mon = MONTHS_FROM_DA9063(data[RTC_MONTH] &
176 config->rtc_count_month_mask);
177 tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
178 config->rtc_count_year_mask);
179 }
180
da9063_tm_to_data(struct rtc_time * tm,u8 * data,struct da9063_compatible_rtc * rtc)181 static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
182 struct da9063_compatible_rtc *rtc)
183 {
184 const struct da9063_compatible_rtc_regmap *config = rtc->config;
185
186 data[RTC_SEC] = tm->tm_sec & config->rtc_count_sec_mask;
187 data[RTC_MIN] = tm->tm_min & config->rtc_count_min_mask;
188 data[RTC_HOUR] = tm->tm_hour & config->rtc_count_hour_mask;
189 data[RTC_DAY] = tm->tm_mday & config->rtc_count_day_mask;
190 data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
191 config->rtc_count_month_mask;
192 data[RTC_YEAR] = YEARS_TO_DA9063(tm->tm_year) &
193 config->rtc_count_year_mask;
194 }
195
da9063_rtc_stop_alarm(struct device * dev)196 static int da9063_rtc_stop_alarm(struct device *dev)
197 {
198 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
199 const struct da9063_compatible_rtc_regmap *config = rtc->config;
200
201 return regmap_update_bits(rtc->regmap,
202 config->rtc_alarm_year_reg,
203 config->rtc_alarm_on_mask,
204 0);
205 }
206
da9063_rtc_start_alarm(struct device * dev)207 static int da9063_rtc_start_alarm(struct device *dev)
208 {
209 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
210 const struct da9063_compatible_rtc_regmap *config = rtc->config;
211
212 return regmap_update_bits(rtc->regmap,
213 config->rtc_alarm_year_reg,
214 config->rtc_alarm_on_mask,
215 config->rtc_alarm_on_mask);
216 }
217
da9063_rtc_read_time(struct device * dev,struct rtc_time * tm)218 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
219 {
220 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
221 const struct da9063_compatible_rtc_regmap *config = rtc->config;
222 unsigned long tm_secs;
223 unsigned long al_secs;
224 u8 data[RTC_DATA_LEN];
225 int ret;
226
227 ret = regmap_bulk_read(rtc->regmap,
228 config->rtc_count_secs_reg,
229 data, RTC_DATA_LEN);
230 if (ret < 0) {
231 dev_err(dev, "Failed to read RTC time data: %d\n", ret);
232 return ret;
233 }
234
235 if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
236 dev_dbg(dev, "RTC not yet ready to be read by the host\n");
237 return -EINVAL;
238 }
239
240 da9063_data_to_tm(data, tm, rtc);
241
242 tm_secs = rtc_tm_to_time64(tm);
243 al_secs = rtc_tm_to_time64(&rtc->alarm_time);
244
245 /* handle the rtc synchronisation delay */
246 if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
247 memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
248 else
249 rtc->rtc_sync = false;
250
251 return 0;
252 }
253
da9063_rtc_set_time(struct device * dev,struct rtc_time * tm)254 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
255 {
256 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
257 const struct da9063_compatible_rtc_regmap *config = rtc->config;
258 u8 data[RTC_DATA_LEN];
259 int ret;
260
261 da9063_tm_to_data(tm, data, rtc);
262 ret = regmap_bulk_write(rtc->regmap,
263 config->rtc_count_secs_reg,
264 data, RTC_DATA_LEN);
265 if (ret < 0)
266 dev_err(dev, "Failed to set RTC time data: %d\n", ret);
267
268 return ret;
269 }
270
da9063_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alrm)271 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
272 {
273 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
274 const struct da9063_compatible_rtc_regmap *config = rtc->config;
275 u8 data[RTC_DATA_LEN];
276 int ret;
277 unsigned int val;
278
279 data[RTC_SEC] = 0;
280 ret = regmap_bulk_read(rtc->regmap,
281 config->rtc_alarm_secs_reg,
282 &data[config->rtc_data_start],
283 config->rtc_alarm_len);
284 if (ret < 0)
285 return ret;
286
287 da9063_data_to_tm(data, &alrm->time, rtc);
288
289 alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);
290
291 ret = regmap_read(rtc->regmap,
292 config->rtc_event_reg,
293 &val);
294 if (ret < 0)
295 return ret;
296
297 if (val & config->rtc_event_alarm_mask)
298 alrm->pending = 1;
299 else
300 alrm->pending = 0;
301
302 return 0;
303 }
304
da9063_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alrm)305 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
306 {
307 struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
308 const struct da9063_compatible_rtc_regmap *config = rtc->config;
309 u8 data[RTC_DATA_LEN];
310 int ret;
311
312 da9063_tm_to_data(&alrm->time, data, rtc);
313
314 ret = da9063_rtc_stop_alarm(dev);
315 if (ret < 0) {
316 dev_err(dev, "Failed to stop alarm: %d\n", ret);
317 return ret;
318 }
319
320 ret = regmap_bulk_write(rtc->regmap,
321 config->rtc_alarm_secs_reg,
322 &data[config->rtc_data_start],
323 config->rtc_alarm_len);
324 if (ret < 0) {
325 dev_err(dev, "Failed to write alarm: %d\n", ret);
326 return ret;
327 }
328
329 da9063_data_to_tm(data, &rtc->alarm_time, rtc);
330
331 if (alrm->enabled) {
332 ret = da9063_rtc_start_alarm(dev);
333 if (ret < 0) {
334 dev_err(dev, "Failed to start alarm: %d\n", ret);
335 return ret;
336 }
337 }
338
339 return ret;
340 }
341
da9063_rtc_alarm_irq_enable(struct device * dev,unsigned int enabled)342 static int da9063_rtc_alarm_irq_enable(struct device *dev,
343 unsigned int enabled)
344 {
345 if (enabled)
346 return da9063_rtc_start_alarm(dev);
347 else
348 return da9063_rtc_stop_alarm(dev);
349 }
350
da9063_alarm_event(int irq,void * data)351 static irqreturn_t da9063_alarm_event(int irq, void *data)
352 {
353 struct da9063_compatible_rtc *rtc = data;
354 const struct da9063_compatible_rtc_regmap *config = rtc->config;
355
356 regmap_update_bits(rtc->regmap,
357 config->rtc_alarm_year_reg,
358 config->rtc_alarm_on_mask,
359 0);
360
361 rtc->rtc_sync = true;
362 rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
363
364 return IRQ_HANDLED;
365 }
366
367 static const struct rtc_class_ops da9063_rtc_ops = {
368 .read_time = da9063_rtc_read_time,
369 .set_time = da9063_rtc_set_time,
370 .read_alarm = da9063_rtc_read_alarm,
371 .set_alarm = da9063_rtc_set_alarm,
372 .alarm_irq_enable = da9063_rtc_alarm_irq_enable,
373 };
374
da9063_rtc_probe(struct platform_device * pdev)375 static int da9063_rtc_probe(struct platform_device *pdev)
376 {
377 struct da9063_compatible_rtc *rtc;
378 const struct da9063_compatible_rtc_regmap *config;
379 const struct of_device_id *match;
380 int irq_alarm;
381 u8 data[RTC_DATA_LEN];
382 int ret;
383
384 if (!pdev->dev.of_node)
385 return -ENXIO;
386
387 match = of_match_node(da9063_compatible_reg_id_table,
388 pdev->dev.of_node);
389
390 rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
391 if (!rtc)
392 return -ENOMEM;
393
394 rtc->config = match->data;
395 if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
396 struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
397
398 if (chip->variant_code == PMIC_DA9063_AD)
399 rtc->config = &da9063_ad_regs;
400 }
401
402 rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
403 if (!rtc->regmap) {
404 dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
405 return -ENXIO;
406 }
407
408 config = rtc->config;
409 ret = regmap_update_bits(rtc->regmap,
410 config->rtc_enable_reg,
411 config->rtc_enable_mask,
412 config->rtc_enable_mask);
413 if (ret < 0) {
414 dev_err(&pdev->dev, "Failed to enable RTC\n");
415 return ret;
416 }
417
418 ret = regmap_update_bits(rtc->regmap,
419 config->rtc_enable_32k_crystal_reg,
420 config->rtc_crystal_mask,
421 config->rtc_crystal_mask);
422 if (ret < 0) {
423 dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
424 return ret;
425 }
426
427 ret = regmap_update_bits(rtc->regmap,
428 config->rtc_alarm_secs_reg,
429 config->rtc_alarm_status_mask,
430 0);
431 if (ret < 0) {
432 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
433 return ret;
434 }
435
436 ret = regmap_update_bits(rtc->regmap,
437 config->rtc_alarm_secs_reg,
438 DA9063_ALARM_STATUS_ALARM,
439 DA9063_ALARM_STATUS_ALARM);
440 if (ret < 0) {
441 dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
442 return ret;
443 }
444
445 ret = regmap_update_bits(rtc->regmap,
446 config->rtc_alarm_year_reg,
447 config->rtc_tick_on_mask,
448 0);
449 if (ret < 0) {
450 dev_err(&pdev->dev, "Failed to disable TICKs\n");
451 return ret;
452 }
453
454 data[RTC_SEC] = 0;
455 ret = regmap_bulk_read(rtc->regmap,
456 config->rtc_alarm_secs_reg,
457 &data[config->rtc_data_start],
458 config->rtc_alarm_len);
459 if (ret < 0) {
460 dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
461 ret);
462 return ret;
463 }
464
465 platform_set_drvdata(pdev, rtc);
466
467 rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
468 if (IS_ERR(rtc->rtc_dev))
469 return PTR_ERR(rtc->rtc_dev);
470
471 rtc->rtc_dev->ops = &da9063_rtc_ops;
472 rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_2000;
473 rtc->rtc_dev->range_max = RTC_TIMESTAMP_END_2063;
474
475 da9063_data_to_tm(data, &rtc->alarm_time, rtc);
476 rtc->rtc_sync = false;
477
478 /*
479 * TODO: some models have alarms on a minute boundary but still support
480 * real hardware interrupts. Add this once the core supports it.
481 */
482 if (config->rtc_data_start != RTC_SEC)
483 rtc->rtc_dev->uie_unsupported = 1;
484
485 irq_alarm = platform_get_irq_byname(pdev, "ALARM");
486 ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
487 da9063_alarm_event,
488 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
489 "ALARM", rtc);
490 if (ret)
491 dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
492 irq_alarm, ret);
493
494 return rtc_register_device(rtc->rtc_dev);
495 }
496
497 static struct platform_driver da9063_rtc_driver = {
498 .probe = da9063_rtc_probe,
499 .driver = {
500 .name = DA9063_DRVNAME_RTC,
501 .of_match_table = da9063_compatible_reg_id_table,
502 },
503 };
504
505 module_platform_driver(da9063_rtc_driver);
506
507 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
508 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
509 MODULE_LICENSE("GPL");
510 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);
511