xref: /openbmc/linux/drivers/rtc/rtc-da9063.c (revision 8bd1369b)
1 /* rtc-da9063.c - Real time clock device driver for DA9063
2  * Copyright (C) 2013-2015  Dialog Semiconductor Ltd.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program 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
12  * GNU 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]   = tm->tm_sec & config->rtc_count_sec_mask;
195 	data[RTC_MIN]   = tm->tm_min & config->rtc_count_min_mask;
196 	data[RTC_HOUR]  = tm->tm_hour & config->rtc_count_hour_mask;
197 	data[RTC_DAY]   = tm->tm_mday & config->rtc_count_day_mask;
198 	data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
199 				config->rtc_count_month_mask;
200 	data[RTC_YEAR]  = YEARS_TO_DA9063(tm->tm_year) &
201 				config->rtc_count_year_mask;
202 }
203 
204 static int da9063_rtc_stop_alarm(struct device *dev)
205 {
206 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
207 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
208 
209 	return regmap_update_bits(rtc->regmap,
210 				  config->rtc_alarm_year_reg,
211 				  config->rtc_alarm_on_mask,
212 				  0);
213 }
214 
215 static int da9063_rtc_start_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 				  config->rtc_alarm_on_mask);
224 }
225 
226 static int da9063_rtc_read_time(struct device *dev, struct rtc_time *tm)
227 {
228 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
229 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
230 	unsigned long tm_secs;
231 	unsigned long al_secs;
232 	u8 data[RTC_DATA_LEN];
233 	int ret;
234 
235 	ret = regmap_bulk_read(rtc->regmap,
236 			       config->rtc_count_secs_reg,
237 			       data, RTC_DATA_LEN);
238 	if (ret < 0) {
239 		dev_err(dev, "Failed to read RTC time data: %d\n", ret);
240 		return ret;
241 	}
242 
243 	if (!(data[RTC_SEC] & config->rtc_ready_to_read_mask)) {
244 		dev_dbg(dev, "RTC not yet ready to be read by the host\n");
245 		return -EINVAL;
246 	}
247 
248 	da9063_data_to_tm(data, tm, rtc);
249 
250 	rtc_tm_to_time(tm, &tm_secs);
251 	rtc_tm_to_time(&rtc->alarm_time, &al_secs);
252 
253 	/* handle the rtc synchronisation delay */
254 	if (rtc->rtc_sync == true && al_secs - tm_secs == 1)
255 		memcpy(tm, &rtc->alarm_time, sizeof(struct rtc_time));
256 	else
257 		rtc->rtc_sync = false;
258 
259 	return 0;
260 }
261 
262 static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
263 {
264 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
265 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
266 	u8 data[RTC_DATA_LEN];
267 	int ret;
268 
269 	da9063_tm_to_data(tm, data, rtc);
270 	ret = regmap_bulk_write(rtc->regmap,
271 				config->rtc_count_secs_reg,
272 				data, RTC_DATA_LEN);
273 	if (ret < 0)
274 		dev_err(dev, "Failed to set RTC time data: %d\n", ret);
275 
276 	return ret;
277 }
278 
279 static int da9063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
280 {
281 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
282 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
283 	u8 data[RTC_DATA_LEN];
284 	int ret;
285 	unsigned int val;
286 
287 	data[RTC_SEC] = 0;
288 	ret = regmap_bulk_read(rtc->regmap,
289 			       config->rtc_alarm_secs_reg,
290 			       &data[config->rtc_data_start],
291 			       config->rtc_alarm_len);
292 	if (ret < 0)
293 		return ret;
294 
295 	da9063_data_to_tm(data, &alrm->time, rtc);
296 
297 	alrm->enabled = !!(data[RTC_YEAR] & config->rtc_alarm_on_mask);
298 
299 	ret = regmap_read(rtc->regmap,
300 			  config->rtc_event_reg,
301 			  &val);
302 	if (ret < 0)
303 		return ret;
304 
305 	if (val & config->rtc_event_alarm_mask)
306 		alrm->pending = 1;
307 	else
308 		alrm->pending = 0;
309 
310 	return 0;
311 }
312 
313 static int da9063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
314 {
315 	struct da9063_compatible_rtc *rtc = dev_get_drvdata(dev);
316 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
317 	u8 data[RTC_DATA_LEN];
318 	int ret;
319 
320 	da9063_tm_to_data(&alrm->time, data, rtc);
321 
322 	ret = da9063_rtc_stop_alarm(dev);
323 	if (ret < 0) {
324 		dev_err(dev, "Failed to stop alarm: %d\n", ret);
325 		return ret;
326 	}
327 
328 	ret = regmap_bulk_write(rtc->regmap,
329 				config->rtc_alarm_secs_reg,
330 				&data[config->rtc_data_start],
331 				config->rtc_alarm_len);
332 	if (ret < 0) {
333 		dev_err(dev, "Failed to write alarm: %d\n", ret);
334 		return ret;
335 	}
336 
337 	da9063_data_to_tm(data, &rtc->alarm_time, rtc);
338 
339 	if (alrm->enabled) {
340 		ret = da9063_rtc_start_alarm(dev);
341 		if (ret < 0) {
342 			dev_err(dev, "Failed to start alarm: %d\n", ret);
343 			return ret;
344 		}
345 	}
346 
347 	return ret;
348 }
349 
350 static int da9063_rtc_alarm_irq_enable(struct device *dev,
351 				       unsigned int enabled)
352 {
353 	if (enabled)
354 		return da9063_rtc_start_alarm(dev);
355 	else
356 		return da9063_rtc_stop_alarm(dev);
357 }
358 
359 static irqreturn_t da9063_alarm_event(int irq, void *data)
360 {
361 	struct da9063_compatible_rtc *rtc = data;
362 	const struct da9063_compatible_rtc_regmap *config = rtc->config;
363 
364 	regmap_update_bits(rtc->regmap,
365 			   config->rtc_alarm_year_reg,
366 			   config->rtc_alarm_on_mask,
367 			   0);
368 
369 	rtc->rtc_sync = true;
370 	rtc_update_irq(rtc->rtc_dev, 1, RTC_IRQF | RTC_AF);
371 
372 	return IRQ_HANDLED;
373 }
374 
375 static const struct rtc_class_ops da9063_rtc_ops = {
376 	.read_time = da9063_rtc_read_time,
377 	.set_time = da9063_rtc_set_time,
378 	.read_alarm = da9063_rtc_read_alarm,
379 	.set_alarm = da9063_rtc_set_alarm,
380 	.alarm_irq_enable = da9063_rtc_alarm_irq_enable,
381 };
382 
383 static int da9063_rtc_probe(struct platform_device *pdev)
384 {
385 	struct da9063_compatible_rtc *rtc;
386 	const struct da9063_compatible_rtc_regmap *config;
387 	const struct of_device_id *match;
388 	int irq_alarm;
389 	u8 data[RTC_DATA_LEN];
390 	int ret;
391 
392 	if (!pdev->dev.of_node)
393 		return -ENXIO;
394 
395 	match = of_match_node(da9063_compatible_reg_id_table,
396 			      pdev->dev.of_node);
397 
398 	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
399 	if (!rtc)
400 		return -ENOMEM;
401 
402 	rtc->config = match->data;
403 	if (of_device_is_compatible(pdev->dev.of_node, "dlg,da9063-rtc")) {
404 		struct da9063 *chip = dev_get_drvdata(pdev->dev.parent);
405 
406 		if (chip->variant_code == PMIC_DA9063_AD)
407 			rtc->config = &da9063_ad_regs;
408 	}
409 
410 	rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
411 	if (!rtc->regmap) {
412 		dev_warn(&pdev->dev, "Parent regmap unavailable.\n");
413 		return -ENXIO;
414 	}
415 
416 	config = rtc->config;
417 	ret = regmap_update_bits(rtc->regmap,
418 				 config->rtc_enable_reg,
419 				 config->rtc_enable_mask,
420 				 config->rtc_enable_mask);
421 	if (ret < 0) {
422 		dev_err(&pdev->dev, "Failed to enable RTC\n");
423 		return ret;
424 	}
425 
426 	ret = regmap_update_bits(rtc->regmap,
427 				 config->rtc_enable_32k_crystal_reg,
428 				 config->rtc_crystal_mask,
429 				 config->rtc_crystal_mask);
430 	if (ret < 0) {
431 		dev_err(&pdev->dev, "Failed to run 32kHz oscillator\n");
432 		return ret;
433 	}
434 
435 	ret = regmap_update_bits(rtc->regmap,
436 				 config->rtc_alarm_secs_reg,
437 				 config->rtc_alarm_status_mask,
438 				 0);
439 	if (ret < 0) {
440 		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
441 		return ret;
442 	}
443 
444 	ret = regmap_update_bits(rtc->regmap,
445 				 config->rtc_alarm_secs_reg,
446 				 DA9063_ALARM_STATUS_ALARM,
447 				 DA9063_ALARM_STATUS_ALARM);
448 	if (ret < 0) {
449 		dev_err(&pdev->dev, "Failed to access RTC alarm register\n");
450 		return ret;
451 	}
452 
453 	ret = regmap_update_bits(rtc->regmap,
454 				 config->rtc_alarm_year_reg,
455 				 config->rtc_tick_on_mask,
456 				 0);
457 	if (ret < 0) {
458 		dev_err(&pdev->dev, "Failed to disable TICKs\n");
459 		return ret;
460 	}
461 
462 	data[RTC_SEC] = 0;
463 	ret = regmap_bulk_read(rtc->regmap,
464 			       config->rtc_alarm_secs_reg,
465 			       &data[config->rtc_data_start],
466 			       config->rtc_alarm_len);
467 	if (ret < 0) {
468 		dev_err(&pdev->dev, "Failed to read initial alarm data: %d\n",
469 			ret);
470 		return ret;
471 	}
472 
473 	platform_set_drvdata(pdev, rtc);
474 
475 	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
476 					   &da9063_rtc_ops, THIS_MODULE);
477 	if (IS_ERR(rtc->rtc_dev))
478 		return PTR_ERR(rtc->rtc_dev);
479 
480 	da9063_data_to_tm(data, &rtc->alarm_time, rtc);
481 	rtc->rtc_sync = false;
482 
483 	irq_alarm = platform_get_irq_byname(pdev, "ALARM");
484 	ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
485 					da9063_alarm_event,
486 					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
487 					"ALARM", rtc);
488 	if (ret)
489 		dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
490 			irq_alarm, ret);
491 
492 	return ret;
493 }
494 
495 static struct platform_driver da9063_rtc_driver = {
496 	.probe		= da9063_rtc_probe,
497 	.driver		= {
498 		.name	= DA9063_DRVNAME_RTC,
499 		.of_match_table = da9063_compatible_reg_id_table,
500 	},
501 };
502 
503 module_platform_driver(da9063_rtc_driver);
504 
505 MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
506 MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
507 MODULE_LICENSE("GPL");
508 MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);
509