xref: /openbmc/linux/drivers/rtc/rtc-da9063.c (revision ca55b2fe)
1 /* rtc-da9063.c - Real time clock device driver for DA9063
2  * Copyright (C) 2013-14  Dialog Semiconductor Ltd.
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Library General Public
6  * License as published by the Free Software Foundation; either
7  * version 2 of the License, or (at your option) any later version.
8  *
9  * This library is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * Library General Public License for more details.
13  */
14 
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/regmap.h>
23 #include <linux/rtc.h>
24 #include <linux/slab.h>
25 
26 #include <linux/mfd/da9062/registers.h>
27 #include <linux/mfd/da9063/registers.h>
28 #include <linux/mfd/da9063/core.h>
29 
30 #define YEARS_TO_DA9063(year)		((year) - 100)
31 #define MONTHS_TO_DA9063(month)		((month) + 1)
32 #define YEARS_FROM_DA9063(year)		((year) + 100)
33 #define MONTHS_FROM_DA9063(month)	((month) - 1)
34 
35 enum {
36 	RTC_SEC	= 0,
37 	RTC_MIN	= 1,
38 	RTC_HOUR = 2,
39 	RTC_DAY	= 3,
40 	RTC_MONTH = 4,
41 	RTC_YEAR = 5,
42 	RTC_DATA_LEN
43 };
44 
45 struct da9063_compatible_rtc_regmap {
46 	/* REGS */
47 	int rtc_enable_reg;
48 	int rtc_enable_32k_crystal_reg;
49 	int rtc_alarm_secs_reg;
50 	int rtc_alarm_year_reg;
51 	int rtc_count_secs_reg;
52 	int rtc_count_year_reg;
53 	int rtc_event_reg;
54 	/* MASKS */
55 	int rtc_enable_mask;
56 	int rtc_crystal_mask;
57 	int rtc_event_alarm_mask;
58 	int rtc_alarm_on_mask;
59 	int rtc_alarm_status_mask;
60 	int rtc_tick_on_mask;
61 	int rtc_ready_to_read_mask;
62 	int rtc_count_sec_mask;
63 	int rtc_count_min_mask;
64 	int rtc_count_hour_mask;
65 	int rtc_count_day_mask;
66 	int rtc_count_month_mask;
67 	int rtc_count_year_mask;
68 	/* ALARM CONFIG */
69 	int rtc_data_start;
70 	int rtc_alarm_len;
71 };
72 
73 struct da9063_compatible_rtc {
74 	struct rtc_device *rtc_dev;
75 	struct rtc_time alarm_time;
76 	struct regmap *regmap;
77 	const struct da9063_compatible_rtc_regmap *config;
78 	bool rtc_sync;
79 };
80 
81 static const struct da9063_compatible_rtc_regmap da9063_ad_regs = {
82 	/* REGS */
83 	.rtc_enable_reg             = DA9063_REG_CONTROL_E,
84 	.rtc_alarm_secs_reg         = DA9063_AD_REG_ALARM_MI,
85 	.rtc_alarm_year_reg         = DA9063_AD_REG_ALARM_Y,
86 	.rtc_count_secs_reg         = DA9063_REG_COUNT_S,
87 	.rtc_count_year_reg         = DA9063_REG_COUNT_Y,
88 	.rtc_event_reg              = DA9063_REG_EVENT_A,
89 	/* MASKS */
90 	.rtc_enable_mask            = DA9063_RTC_EN,
91 	.rtc_crystal_mask           = DA9063_CRYSTAL,
92 	.rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
93 	.rtc_event_alarm_mask       = DA9063_E_ALARM,
94 	.rtc_alarm_on_mask          = DA9063_ALARM_ON,
95 	.rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
96 				      DA9063_ALARM_STATUS_TICK,
97 	.rtc_tick_on_mask           = DA9063_TICK_ON,
98 	.rtc_ready_to_read_mask     = DA9063_RTC_READ,
99 	.rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
100 	.rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
101 	.rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
102 	.rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
103 	.rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
104 	.rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
105 	/* ALARM CONFIG */
106 	.rtc_data_start             = RTC_MIN,
107 	.rtc_alarm_len              = RTC_DATA_LEN - 1,
108 };
109 
110 static const struct da9063_compatible_rtc_regmap da9063_bb_regs = {
111 	/* REGS */
112 	.rtc_enable_reg             = DA9063_REG_CONTROL_E,
113 	.rtc_alarm_secs_reg         = DA9063_BB_REG_ALARM_S,
114 	.rtc_alarm_year_reg         = DA9063_BB_REG_ALARM_Y,
115 	.rtc_count_secs_reg         = DA9063_REG_COUNT_S,
116 	.rtc_count_year_reg         = DA9063_REG_COUNT_Y,
117 	.rtc_event_reg              = DA9063_REG_EVENT_A,
118 	/* MASKS */
119 	.rtc_enable_mask            = DA9063_RTC_EN,
120 	.rtc_crystal_mask           = DA9063_CRYSTAL,
121 	.rtc_enable_32k_crystal_reg = DA9063_REG_EN_32K,
122 	.rtc_event_alarm_mask       = DA9063_E_ALARM,
123 	.rtc_alarm_on_mask          = DA9063_ALARM_ON,
124 	.rtc_alarm_status_mask      = DA9063_ALARM_STATUS_ALARM |
125 				      DA9063_ALARM_STATUS_TICK,
126 	.rtc_tick_on_mask           = DA9063_TICK_ON,
127 	.rtc_ready_to_read_mask     = DA9063_RTC_READ,
128 	.rtc_count_sec_mask         = DA9063_COUNT_SEC_MASK,
129 	.rtc_count_min_mask         = DA9063_COUNT_MIN_MASK,
130 	.rtc_count_hour_mask        = DA9063_COUNT_HOUR_MASK,
131 	.rtc_count_day_mask         = DA9063_COUNT_DAY_MASK,
132 	.rtc_count_month_mask       = DA9063_COUNT_MONTH_MASK,
133 	.rtc_count_year_mask        = DA9063_COUNT_YEAR_MASK,
134 	/* ALARM CONFIG */
135 	.rtc_data_start             = RTC_SEC,
136 	.rtc_alarm_len              = RTC_DATA_LEN,
137 };
138 
139 static const struct da9063_compatible_rtc_regmap da9062_aa_regs = {
140 	/* REGS */
141 	.rtc_enable_reg             = DA9062AA_CONTROL_E,
142 	.rtc_alarm_secs_reg         = DA9062AA_ALARM_S,
143 	.rtc_alarm_year_reg         = DA9062AA_ALARM_Y,
144 	.rtc_count_secs_reg         = DA9062AA_COUNT_S,
145 	.rtc_count_year_reg         = DA9062AA_COUNT_Y,
146 	.rtc_event_reg              = DA9062AA_EVENT_A,
147 	/* MASKS */
148 	.rtc_enable_mask            = DA9062AA_RTC_EN_MASK,
149 	.rtc_crystal_mask           = DA9062AA_CRYSTAL_MASK,
150 	.rtc_enable_32k_crystal_reg = DA9062AA_EN_32K,
151 	.rtc_event_alarm_mask       = DA9062AA_M_ALARM_MASK,
152 	.rtc_alarm_on_mask          = DA9062AA_ALARM_ON_MASK,
153 	.rtc_alarm_status_mask      = (0x02 << 6),
154 	.rtc_tick_on_mask           = DA9062AA_TICK_ON_MASK,
155 	.rtc_ready_to_read_mask     = DA9062AA_RTC_READ_MASK,
156 	.rtc_count_sec_mask         = DA9062AA_COUNT_SEC_MASK,
157 	.rtc_count_min_mask         = DA9062AA_COUNT_MIN_MASK,
158 	.rtc_count_hour_mask        = DA9062AA_COUNT_HOUR_MASK,
159 	.rtc_count_day_mask         = DA9062AA_COUNT_DAY_MASK,
160 	.rtc_count_month_mask       = DA9062AA_COUNT_MONTH_MASK,
161 	.rtc_count_year_mask        = DA9062AA_COUNT_YEAR_MASK,
162 	/* ALARM CONFIG */
163 	.rtc_data_start             = RTC_SEC,
164 	.rtc_alarm_len              = RTC_DATA_LEN,
165 };
166 
167 static const struct of_device_id da9063_compatible_reg_id_table[] = {
168 	{ .compatible = "dlg,da9063-rtc", .data = &da9063_bb_regs },
169 	{ .compatible = "dlg,da9062-rtc", .data = &da9062_aa_regs },
170 	{ },
171 };
172 MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);
173 
174 static void da9063_data_to_tm(u8 *data, struct rtc_time *tm,
175 			      struct da9063_compatible_rtc *rtc)
176 {
177 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
178 
179 	tm->tm_sec  = data[RTC_SEC]  & config->rtc_count_sec_mask;
180 	tm->tm_min  = data[RTC_MIN]  & config->rtc_count_min_mask;
181 	tm->tm_hour = data[RTC_HOUR] & config->rtc_count_hour_mask;
182 	tm->tm_mday = data[RTC_DAY]  & config->rtc_count_day_mask;
183 	tm->tm_mon  = MONTHS_FROM_DA9063(data[RTC_MONTH] &
184 					 config->rtc_count_month_mask);
185 	tm->tm_year = YEARS_FROM_DA9063(data[RTC_YEAR] &
186 					config->rtc_count_year_mask);
187 }
188 
189 static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
190 			      struct da9063_compatible_rtc *rtc)
191 {
192 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
193 
194 	data[RTC_SEC] &= ~config->rtc_count_sec_mask;
195 	data[RTC_SEC] |= tm->tm_sec & config->rtc_count_sec_mask;
196 
197 	data[RTC_MIN] &= ~config->rtc_count_min_mask;
198 	data[RTC_MIN] |= tm->tm_min & config->rtc_count_min_mask;
199 
200 	data[RTC_HOUR] &= ~config->rtc_count_hour_mask;
201 	data[RTC_HOUR] |= tm->tm_hour & config->rtc_count_hour_mask;
202 
203 	data[RTC_DAY] &= ~config->rtc_count_day_mask;
204 	data[RTC_DAY] |= tm->tm_mday & config->rtc_count_day_mask;
205 
206 	data[RTC_MONTH] &= ~config->rtc_count_month_mask;
207 	data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
208 				config->rtc_count_month_mask;
209 
210 	data[RTC_YEAR] &= ~config->rtc_count_year_mask;
211 	data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
212 				config->rtc_count_year_mask;
213 }
214 
215 static int da9063_rtc_stop_alarm(struct device *dev)
216 {
217 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
218 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
219 
220 	return regmap_update_bits(rtc->regmap,
221 				  config->rtc_alarm_year_reg,
222 				  config->rtc_alarm_on_mask,
223 				  0);
224 }
225 
226 static int da9063_rtc_start_alarm(struct device *dev)
227 {
228 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
229 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
230 
231 	return regmap_update_bits(rtc->regmap,
232 				  config->rtc_alarm_year_reg,
233 				  config->rtc_alarm_on_mask,
234 				  config->rtc_alarm_on_mask);
235 }
236 
237 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
238 {
239 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
240 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
241 	unsigned long tm_secs;
242 	unsigned long al_secs;
243 	u8 data[RTC_DATA_LEN];
244 	int ret;
245 
246 	ret = regmap_bulk_read(rtc->regmap,
247 			       config->rtc_count_secs_reg,
248 			       data, RTC_DATA_LEN);
249 	if (ret < 0) {
250 		dev_err(dev, "Failed to read RTC time data: %d\n", ret);
251 		return ret;
252 	}
253 
254 	if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
255 		dev_dbg(dev, "RTC not yet ready to be read by the host\n");
256 		return -EINVAL;
257 	}
258 
259 	da9063_data_to_tm(data, tm, rtc);
260 
261 	rtc_tm_to_time(tm, &tm_secs);
262 	rtc_tm_to_time(&rtc->alarm_time, &al_secs);
263 
264 	/* handle the rtc synchronisation delay */
265 	if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
266 		memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
267 	else
268 		rtc->rtc_sync = false;
269 
270 	return rtc_valid_tm(tm);
271 }
272 
273 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
274 {
275 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
276 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
277 	u8 data[RTC_DATA_LEN];
278 	int ret;
279 
280 	da9063_tm_to_data(tm, data, rtc);
281 	ret = regmap_bulk_write(rtc->regmap,
282 				config->rtc_count_secs_reg,
283 				data, RTC_DATA_LEN);
284 	if (ret < 0)
285 		dev_err(dev, "Failed to set RTC time data: %d\n", ret);
286 
287 	return ret;
288 }
289 
290 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
291 {
292 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
293 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
294 	u8 data[RTC_DATA_LEN];
295 	int ret;
296 	unsigned int val;
297 
298 	data[RTC_SEC] = 0;
299 	ret = regmap_bulk_read(rtc->regmap,
300 			       config->rtc_alarm_secs_reg,
301 			       &data[config->rtc_data_start],
302 			       config->rtc_alarm_len);
303 	if (ret < 0)
304 		return ret;
305 
306 	da9063_data_to_tm(data, &alrm->time, rtc);
307 
308 	alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);
309 
310 	ret = regmap_read(rtc->regmap,
311 			  config->rtc_event_reg,
312 			  &val);
313 	if (ret < 0)
314 		return ret;
315 
316 	if (val & config->rtc_event_alarm_mask)
317 		alrm->pending = 1;
318 	else
319 		alrm->pending = 0;
320 
321 	return 0;
322 }
323 
324 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
325 {
326 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
327 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
328 	u8 data[RTC_DATA_LEN];
329 	int ret;
330 
331 	da9063_tm_to_data(&alrm->time, data, rtc);
332 
333 	ret = da9063_rtc_stop_alarm(dev);
334 	if (ret < 0) {
335 		dev_err(dev, "Failed to stop alarm: %d\n", ret);
336 		return ret;
337 	}
338 
339 	ret = regmap_bulk_write(rtc->regmap,
340 				config->rtc_alarm_secs_reg,
341 				&data[config->rtc_data_start],
342 				config->rtc_alarm_len);
343 	if (ret < 0) {
344 		dev_err(dev, "Failed to write alarm: %d\n", ret);
345 		return ret;
346 	}
347 
348 	da9063_data_to_tm(data, &rtc->alarm_time, rtc);
349 
350 	if (alrm->enabled) {
351 		ret = da9063_rtc_start_alarm(dev);
352 		if (ret < 0) {
353 			dev_err(dev, "Failed to start alarm: %d\n", ret);
354 			return ret;
355 		}
356 	}
357 
358 	return ret;
359 }
360 
361 static int da9063_rtc_alarm_irq_enable(struct device *dev,
362 				       unsigned int enabled)
363 {
364 	if (enabled)
365 		return da9063_rtc_start_alarm(dev);
366 	else
367 		return da9063_rtc_stop_alarm(dev);
368 }
369 
370 static irqreturn_t da9063_alarm_event(int irq, void *data)
371 {
372 	struct da9063_compatible_rtc *rtc = data;
373 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
374 
375 	regmap_update_bits(rtc->regmap,
376 			   config->rtc_alarm_year_reg,
377 			   config->rtc_alarm_on_mask,
378 			   0);
379 
380 	rtc->rtc_sync = true;
381 	rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
382 
383 	return IRQ_HANDLED;
384 }
385 
386 static const struct rtc_class_ops da9063_rtc_ops = {
387 	.read_time = da9063_rtc_read_time,
388 	.set_time = da9063_rtc_set_time,
389 	.read_alarm = da9063_rtc_read_alarm,
390 	.set_alarm = da9063_rtc_set_alarm,
391 	.alarm_irq_enable = da9063_rtc_alarm_irq_enable,
392 };
393 
394 static int da9063_rtc_probe(struct platform_device *pdev)
395 {
396 	struct da9063_compatible_rtc *rtc;
397 	const struct da9063_compatible_rtc_regmap *config;
398 	const struct of_device_id *match;
399 	int irq_alarm;
400 	u8 data[RTC_DATA_LEN];
401 	int ret;
402 
403 	if (!pdev->dev.of_node)
404 		return -ENXIO;
405 
406 	match = of_match_node(da9063_compatible_reg_id_table,
407 			      pdev->dev.of_node);
408 
409 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
410 	if (!rtc)
411 		return -ENOMEM;
412 
413 	rtc->config = match->data;
414 	if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
415 		struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
416 
417 		if (chip->variant_code == PMIC_DA9063_AD)
418 			rtc->config = &da9063_ad_regs;
419 	}
420 
421 	rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
422 	if (!rtc->regmap) {
423 		dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
424 		return -ENXIO;
425 	}
426 
427 	config = rtc->config;
428 	ret = regmap_update_bits(rtc->regmap,
429 				 config->rtc_enable_reg,
430 				 config->rtc_enable_mask,
431 				 config->rtc_enable_mask);
432 	if (ret < 0) {
433 		dev_err(&pdev->dev, "Failed to enable RTC\n");
434 		return ret;
435 	}
436 
437 	ret = regmap_update_bits(rtc->regmap,
438 				 config->rtc_enable_32k_crystal_reg,
439 				 config->rtc_crystal_mask,
440 				 config->rtc_crystal_mask);
441 	if (ret < 0) {
442 		dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
443 		return ret;
444 	}
445 
446 	ret = regmap_update_bits(rtc->regmap,
447 				 config->rtc_alarm_secs_reg,
448 				 config->rtc_alarm_status_mask,
449 				 0);
450 	if (ret < 0) {
451 		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
452 		return ret;
453 	}
454 
455 	ret = regmap_update_bits(rtc->regmap,
456 				 config->rtc_alarm_secs_reg,
457 				 DA9063_ALARM_STATUS_ALARM,
458 				 DA9063_ALARM_STATUS_ALARM);
459 	if (ret < 0) {
460 		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
461 		return ret;
462 	}
463 
464 	ret = regmap_update_bits(rtc->regmap,
465 				 config->rtc_alarm_year_reg,
466 				 config->rtc_tick_on_mask,
467 				 0);
468 	if (ret < 0) {
469 		dev_err(&pdev->dev, "Failed to disable TICKs\n");
470 		return ret;
471 	}
472 
473 	data[RTC_SEC] = 0;
474 	ret = regmap_bulk_read(rtc->regmap,
475 			       config->rtc_alarm_secs_reg,
476 			       &data[config->rtc_data_start],
477 			       config->rtc_alarm_len);
478 	if (ret < 0) {
479 		dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
480 			ret);
481 		return ret;
482 	}
483 
484 	platform_set_drvdata(pdev, rtc);
485 
486 	irq_alarm = platform_get_irq_byname(pdev, "ALARM");
487 	ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
488 					da9063_alarm_event,
489 					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
490 					"ALARM", rtc);
491 	if (ret) {
492 		dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
493 			irq_alarm, ret);
494 		return ret;
495 	}
496 
497 	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
498 					   &da9063_rtc_ops, THIS_MODULE);
499 	if (IS_ERR(rtc->rtc_dev))
500 		return PTR_ERR(rtc->rtc_dev);
501 
502 	da9063_data_to_tm(data, &rtc->alarm_time, rtc);
503 	rtc->rtc_sync = false;
504 	return ret;
505 }
506 
507 static struct platform_driver da9063_rtc_driver = {
508 	.probe		= da9063_rtc_probe,
509 	.driver		= {
510 		.name	= DA9063_DRVNAME_RTC,
511 		.of_match_table = da9063_compatible_reg_id_table,
512 	},
513 };
514 
515 module_platform_driver(da9063_rtc_driver);
516 
517 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
518 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
519 MODULE_LICENSE("GPL v2");
520 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);
521