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
35enum {
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
45struct 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
73struct 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
81static 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
110static 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
139static 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
167static 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};
172MODULE_DEVICE_TABLE(of, da9063_compatible_reg_id_table);
173
174static 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
189static 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
215static 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
226static 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
237static 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
273static 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
290static 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
324static 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
361static 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
370static 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
386static 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
394static 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	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, DA9063_DRVNAME_RTC,
487					   &da9063_rtc_ops, THIS_MODULE);
488	if (IS_ERR(rtc->rtc_dev))
489		return PTR_ERR(rtc->rtc_dev);
490
491	da9063_data_to_tm(data, &rtc->alarm_time, rtc);
492	rtc->rtc_sync = false;
493
494	irq_alarm = platform_get_irq_byname(pdev, "ALARM");
495	ret = devm_request_threaded_irq(&pdev->dev, irq_alarm, NULL,
496					da9063_alarm_event,
497					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
498					"ALARM", rtc);
499	if (ret)
500		dev_err(&pdev->dev, "Failed to request ALARM IRQ %d: %d\n",
501			irq_alarm, ret);
502
503	return ret;
504}
505
506static struct platform_driver da9063_rtc_driver = {
507	.probe		= da9063_rtc_probe,
508	.driver		= {
509		.name	= DA9063_DRVNAME_RTC,
510		.of_match_table = da9063_compatible_reg_id_table,
511	},
512};
513
514module_platform_driver(da9063_rtc_driver);
515
516MODULE_AUTHOR("S Twiss <stwiss.opensource@diasemi.com>");
517MODULE_DESCRIPTION("Real time clock device driver for Dialog DA9063");
518MODULE_LICENSE("GPL");
519MODULE_ALIAS("platform:" DA9063_DRVNAME_RTC);
520