rtc-da9063.c

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