1// SPDX-License-Identifier: GPL-2.0
2/*
3 * RTC driver for the Micro Crystal RV3032
4 *
5 * Copyright (C) 2020 Micro Crystal SA
6 *
7 * Alexandre Belloni <alexandre.belloni@bootlin.com>
8 *
9 */
10
11#include <linux/clk.h>
12#include <linux/clk-provider.h>
13#include <linux/bcd.h>
14#include <linux/bitfield.h>
15#include <linux/bitops.h>
16#include <linux/hwmon.h>
17#include <linux/i2c.h>
18#include <linux/interrupt.h>
19#include <linux/kernel.h>
20#include <linux/log2.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/regmap.h>
24#include <linux/rtc.h>
25
26#define RV3032_SEC			0x01
27#define RV3032_MIN			0x02
28#define RV3032_HOUR			0x03
29#define RV3032_WDAY			0x04
30#define RV3032_DAY			0x05
31#define RV3032_MONTH			0x06
32#define RV3032_YEAR			0x07
33#define RV3032_ALARM_MIN		0x08
34#define RV3032_ALARM_HOUR		0x09
35#define RV3032_ALARM_DAY		0x0A
36#define RV3032_STATUS			0x0D
37#define RV3032_TLSB			0x0E
38#define RV3032_TMSB			0x0F
39#define RV3032_CTRL1			0x10
40#define RV3032_CTRL2			0x11
41#define RV3032_CTRL3			0x12
42#define RV3032_TS_CTRL			0x13
43#define RV3032_CLK_IRQ			0x14
44#define RV3032_EEPROM_ADDR		0x3D
45#define RV3032_EEPROM_DATA		0x3E
46#define RV3032_EEPROM_CMD		0x3F
47#define RV3032_RAM1			0x40
48#define RV3032_PMU			0xC0
49#define RV3032_OFFSET			0xC1
50#define RV3032_CLKOUT1			0xC2
51#define RV3032_CLKOUT2			0xC3
52#define RV3032_TREF0			0xC4
53#define RV3032_TREF1			0xC5
54
55#define RV3032_STATUS_VLF		BIT(0)
56#define RV3032_STATUS_PORF		BIT(1)
57#define RV3032_STATUS_EVF		BIT(2)
58#define RV3032_STATUS_AF		BIT(3)
59#define RV3032_STATUS_TF		BIT(4)
60#define RV3032_STATUS_UF		BIT(5)
61#define RV3032_STATUS_TLF		BIT(6)
62#define RV3032_STATUS_THF		BIT(7)
63
64#define RV3032_TLSB_CLKF		BIT(1)
65#define RV3032_TLSB_EEBUSY		BIT(2)
66#define RV3032_TLSB_TEMP		GENMASK(7, 4)
67
68#define RV3032_CLKOUT2_HFD_MSK		GENMASK(4, 0)
69#define RV3032_CLKOUT2_FD_MSK		GENMASK(6, 5)
70#define RV3032_CLKOUT2_OS		BIT(7)
71
72#define RV3032_CTRL1_EERD		BIT(3)
73#define RV3032_CTRL1_WADA		BIT(5)
74
75#define RV3032_CTRL2_STOP		BIT(0)
76#define RV3032_CTRL2_EIE		BIT(2)
77#define RV3032_CTRL2_AIE		BIT(3)
78#define RV3032_CTRL2_TIE		BIT(4)
79#define RV3032_CTRL2_UIE		BIT(5)
80#define RV3032_CTRL2_CLKIE		BIT(6)
81#define RV3032_CTRL2_TSE		BIT(7)
82
83#define RV3032_PMU_TCM			GENMASK(1, 0)
84#define RV3032_PMU_TCR			GENMASK(3, 2)
85#define RV3032_PMU_BSM			GENMASK(5, 4)
86#define RV3032_PMU_NCLKE		BIT(6)
87
88#define RV3032_PMU_BSM_DSM		1
89#define RV3032_PMU_BSM_LSM		2
90
91#define RV3032_OFFSET_MSK		GENMASK(5, 0)
92
93#define RV3032_EVT_CTRL_TSR		BIT(2)
94
95#define RV3032_EEPROM_CMD_UPDATE	0x11
96#define RV3032_EEPROM_CMD_WRITE		0x21
97#define RV3032_EEPROM_CMD_READ		0x22
98
99#define RV3032_EEPROM_USER		0xCB
100
101#define RV3032_EEBUSY_POLL		10000
102#define RV3032_EEBUSY_TIMEOUT		100000
103
104#define OFFSET_STEP_PPT			238419
105
106struct rv3032_data {
107	struct regmap *regmap;
108	struct rtc_device *rtc;
109	bool trickle_charger_set;
110#ifdef CONFIG_COMMON_CLK
111	struct clk_hw clkout_hw;
112#endif
113};
114
115static u16 rv3032_trickle_resistors[] = {1000, 2000, 7000, 11000};
116static u16 rv3032_trickle_voltages[] = {0, 1750, 3000, 4400};
117
118static int rv3032_exit_eerd(struct rv3032_data *rv3032, u32 eerd)
119{
120	if (eerd)
121		return 0;
122
123	return regmap_update_bits(rv3032->regmap, RV3032_CTRL1, RV3032_CTRL1_EERD, 0);
124}
125
126static int rv3032_enter_eerd(struct rv3032_data *rv3032, u32 *eerd)
127{
128	u32 ctrl1, status;
129	int ret;
130
131	ret = regmap_read(rv3032->regmap, RV3032_CTRL1, &ctrl1);
132	if (ret)
133		return ret;
134
135	*eerd = ctrl1 & RV3032_CTRL1_EERD;
136	if (*eerd)
137		return 0;
138
139	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL1,
140				 RV3032_CTRL1_EERD, RV3032_CTRL1_EERD);
141	if (ret)
142		return ret;
143
144	ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
145				       !(status & RV3032_TLSB_EEBUSY),
146				       RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
147	if (ret) {
148		rv3032_exit_eerd(rv3032, *eerd);
149
150		return ret;
151	}
152
153	return 0;
154}
155
156static int rv3032_update_cfg(struct rv3032_data *rv3032, unsigned int reg,
157			     unsigned int mask, unsigned int val)
158{
159	u32 status, eerd;
160	int ret;
161
162	ret = rv3032_enter_eerd(rv3032, &eerd);
163	if (ret)
164		return ret;
165
166	ret = regmap_update_bits(rv3032->regmap, reg, mask, val);
167	if (ret)
168		goto exit_eerd;
169
170	ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD, RV3032_EEPROM_CMD_UPDATE);
171	if (ret)
172		goto exit_eerd;
173
174	usleep_range(46000, RV3032_EEBUSY_TIMEOUT);
175
176	ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
177				       !(status & RV3032_TLSB_EEBUSY),
178				       RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
179
180exit_eerd:
181	rv3032_exit_eerd(rv3032, eerd);
182
183	return ret;
184}
185
186static irqreturn_t rv3032_handle_irq(int irq, void *dev_id)
187{
188	struct rv3032_data *rv3032 = dev_id;
189	unsigned long events = 0;
190	u32 status = 0, ctrl = 0;
191
192	if (regmap_read(rv3032->regmap, RV3032_STATUS, &status) < 0 ||
193	    status == 0) {
194		return IRQ_NONE;
195	}
196
197	if (status & RV3032_STATUS_TF) {
198		status |= RV3032_STATUS_TF;
199		ctrl |= RV3032_CTRL2_TIE;
200		events |= RTC_PF;
201	}
202
203	if (status & RV3032_STATUS_AF) {
204		status |= RV3032_STATUS_AF;
205		ctrl |= RV3032_CTRL2_AIE;
206		events |= RTC_AF;
207	}
208
209	if (status & RV3032_STATUS_UF) {
210		status |= RV3032_STATUS_UF;
211		ctrl |= RV3032_CTRL2_UIE;
212		events |= RTC_UF;
213	}
214
215	if (events) {
216		rtc_update_irq(rv3032->rtc, 1, events);
217		regmap_update_bits(rv3032->regmap, RV3032_STATUS, status, 0);
218		regmap_update_bits(rv3032->regmap, RV3032_CTRL2, ctrl, 0);
219	}
220
221	return IRQ_HANDLED;
222}
223
224static int rv3032_get_time(struct device *dev, struct rtc_time *tm)
225{
226	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
227	u8 date[7];
228	int ret, status;
229
230	ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
231	if (ret < 0)
232		return ret;
233
234	if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
235		return -EINVAL;
236
237	ret = regmap_bulk_read(rv3032->regmap, RV3032_SEC, date, sizeof(date));
238	if (ret)
239		return ret;
240
241	tm->tm_sec  = bcd2bin(date[0] & 0x7f);
242	tm->tm_min  = bcd2bin(date[1] & 0x7f);
243	tm->tm_hour = bcd2bin(date[2] & 0x3f);
244	tm->tm_wday = date[3] & 0x7;
245	tm->tm_mday = bcd2bin(date[4] & 0x3f);
246	tm->tm_mon  = bcd2bin(date[5] & 0x1f) - 1;
247	tm->tm_year = bcd2bin(date[6]) + 100;
248
249	return 0;
250}
251
252static int rv3032_set_time(struct device *dev, struct rtc_time *tm)
253{
254	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
255	u8 date[7];
256	int ret;
257
258	date[0] = bin2bcd(tm->tm_sec);
259	date[1] = bin2bcd(tm->tm_min);
260	date[2] = bin2bcd(tm->tm_hour);
261	date[3] = tm->tm_wday;
262	date[4] = bin2bcd(tm->tm_mday);
263	date[5] = bin2bcd(tm->tm_mon + 1);
264	date[6] = bin2bcd(tm->tm_year - 100);
265
266	ret = regmap_bulk_write(rv3032->regmap, RV3032_SEC, date,
267				sizeof(date));
268	if (ret)
269		return ret;
270
271	ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
272				 RV3032_STATUS_PORF | RV3032_STATUS_VLF, 0);
273
274	return ret;
275}
276
277static int rv3032_get_alarm(struct device *dev, struct rtc_wkalrm *alrm)
278{
279	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
280	u8 alarmvals[3];
281	int status, ctrl, ret;
282
283	ret = regmap_bulk_read(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
284			       sizeof(alarmvals));
285	if (ret)
286		return ret;
287
288	ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
289	if (ret < 0)
290		return ret;
291
292	ret = regmap_read(rv3032->regmap, RV3032_CTRL2, &ctrl);
293	if (ret < 0)
294		return ret;
295
296	alrm->time.tm_sec  = 0;
297	alrm->time.tm_min  = bcd2bin(alarmvals[0] & 0x7f);
298	alrm->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
299	alrm->time.tm_mday = bcd2bin(alarmvals[2] & 0x3f);
300
301	alrm->enabled = !!(ctrl & RV3032_CTRL2_AIE);
302	alrm->pending = (status & RV3032_STATUS_AF) && alrm->enabled;
303
304	return 0;
305}
306
307static int rv3032_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
308{
309	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
310	u8 alarmvals[3];
311	u8 ctrl = 0;
312	int ret;
313
314	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
315				 RV3032_CTRL2_AIE | RV3032_CTRL2_UIE, 0);
316	if (ret)
317		return ret;
318
319	alarmvals[0] = bin2bcd(alrm->time.tm_min);
320	alarmvals[1] = bin2bcd(alrm->time.tm_hour);
321	alarmvals[2] = bin2bcd(alrm->time.tm_mday);
322
323	ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
324				 RV3032_STATUS_AF, 0);
325	if (ret)
326		return ret;
327
328	ret = regmap_bulk_write(rv3032->regmap, RV3032_ALARM_MIN, alarmvals,
329				sizeof(alarmvals));
330	if (ret)
331		return ret;
332
333	if (alrm->enabled) {
334		if (rv3032->rtc->uie_rtctimer.enabled)
335			ctrl |= RV3032_CTRL2_UIE;
336		if (rv3032->rtc->aie_timer.enabled)
337			ctrl |= RV3032_CTRL2_AIE;
338	}
339
340	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
341				 RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
342
343	return ret;
344}
345
346static int rv3032_alarm_irq_enable(struct device *dev, unsigned int enabled)
347{
348	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
349	int ctrl = 0, ret;
350
351	if (enabled) {
352		if (rv3032->rtc->uie_rtctimer.enabled)
353			ctrl |= RV3032_CTRL2_UIE;
354		if (rv3032->rtc->aie_timer.enabled)
355			ctrl |= RV3032_CTRL2_AIE;
356	}
357
358	ret = regmap_update_bits(rv3032->regmap, RV3032_STATUS,
359				 RV3032_STATUS_AF | RV3032_STATUS_UF, 0);
360	if (ret)
361		return ret;
362
363	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2,
364				 RV3032_CTRL2_UIE | RV3032_CTRL2_AIE, ctrl);
365	if (ret)
366		return ret;
367
368	return 0;
369}
370
371static int rv3032_read_offset(struct device *dev, long *offset)
372{
373	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
374	int ret, value, steps;
375
376	ret = regmap_read(rv3032->regmap, RV3032_OFFSET, &value);
377	if (ret < 0)
378		return ret;
379
380	steps = sign_extend32(FIELD_GET(RV3032_OFFSET_MSK, value), 5);
381
382	*offset = DIV_ROUND_CLOSEST(steps * OFFSET_STEP_PPT, 1000);
383
384	return 0;
385}
386
387static int rv3032_set_offset(struct device *dev, long offset)
388{
389	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
390
391	offset = clamp(offset, -7629L, 7391L) * 1000;
392	offset = DIV_ROUND_CLOSEST(offset, OFFSET_STEP_PPT);
393
394	return rv3032_update_cfg(rv3032, RV3032_OFFSET, RV3032_OFFSET_MSK,
395				 FIELD_PREP(RV3032_OFFSET_MSK, offset));
396}
397
398static int rv3032_param_get(struct device *dev, struct rtc_param *param)
399{
400	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
401	int ret;
402
403	switch(param->param) {
404		u32 value;
405
406	case RTC_PARAM_BACKUP_SWITCH_MODE:
407		ret = regmap_read(rv3032->regmap, RV3032_PMU, &value);
408		if (ret < 0)
409			return ret;
410
411		value = FIELD_GET(RV3032_PMU_BSM, value);
412
413		switch(value) {
414		case RV3032_PMU_BSM_DSM:
415			param->uvalue = RTC_BSM_DIRECT;
416			break;
417		case RV3032_PMU_BSM_LSM:
418			param->uvalue = RTC_BSM_LEVEL;
419			break;
420		default:
421			param->uvalue = RTC_BSM_DISABLED;
422		}
423
424		break;
425
426	default:
427		return -EINVAL;
428	}
429
430	return 0;
431}
432
433static int rv3032_param_set(struct device *dev, struct rtc_param *param)
434{
435	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
436
437	switch(param->param) {
438		u8 mode;
439	case RTC_PARAM_BACKUP_SWITCH_MODE:
440		if (rv3032->trickle_charger_set)
441			return -EINVAL;
442
443		switch (param->uvalue) {
444		case RTC_BSM_DISABLED:
445			mode = 0;
446			break;
447		case RTC_BSM_DIRECT:
448			mode = RV3032_PMU_BSM_DSM;
449			break;
450		case RTC_BSM_LEVEL:
451			mode = RV3032_PMU_BSM_LSM;
452			break;
453		default:
454			return -EINVAL;
455		}
456
457		return rv3032_update_cfg(rv3032, RV3032_PMU, RV3032_PMU_BSM,
458					 FIELD_PREP(RV3032_PMU_BSM, mode));
459
460	default:
461		return -EINVAL;
462	}
463
464	return 0;
465}
466
467static int rv3032_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
468{
469	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
470	int status, val = 0, ret = 0;
471
472	switch (cmd) {
473	case RTC_VL_READ:
474		ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
475		if (ret < 0)
476			return ret;
477
478		if (status & (RV3032_STATUS_PORF | RV3032_STATUS_VLF))
479			val = RTC_VL_DATA_INVALID;
480		return put_user(val, (unsigned int __user *)arg);
481
482	default:
483		return -ENOIOCTLCMD;
484	}
485}
486
487static int rv3032_nvram_write(void *priv, unsigned int offset, void *val, size_t bytes)
488{
489	return regmap_bulk_write(priv, RV3032_RAM1 + offset, val, bytes);
490}
491
492static int rv3032_nvram_read(void *priv, unsigned int offset, void *val, size_t bytes)
493{
494	return regmap_bulk_read(priv, RV3032_RAM1 + offset, val, bytes);
495}
496
497static int rv3032_eeprom_write(void *priv, unsigned int offset, void *val, size_t bytes)
498{
499	struct rv3032_data *rv3032 = priv;
500	u32 status, eerd;
501	int i, ret;
502	u8 *buf = val;
503
504	ret = rv3032_enter_eerd(rv3032, &eerd);
505	if (ret)
506		return ret;
507
508	for (i = 0; i < bytes; i++) {
509		ret = regmap_write(rv3032->regmap, RV3032_EEPROM_ADDR,
510				   RV3032_EEPROM_USER + offset + i);
511		if (ret)
512			goto exit_eerd;
513
514		ret = regmap_write(rv3032->regmap, RV3032_EEPROM_DATA, buf[i]);
515		if (ret)
516			goto exit_eerd;
517
518		ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD,
519				   RV3032_EEPROM_CMD_WRITE);
520		if (ret)
521			goto exit_eerd;
522
523		usleep_range(RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
524
525		ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
526					       !(status & RV3032_TLSB_EEBUSY),
527					       RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
528		if (ret)
529			goto exit_eerd;
530	}
531
532exit_eerd:
533	rv3032_exit_eerd(rv3032, eerd);
534
535	return ret;
536}
537
538static int rv3032_eeprom_read(void *priv, unsigned int offset, void *val, size_t bytes)
539{
540	struct rv3032_data *rv3032 = priv;
541	u32 status, eerd, data;
542	int i, ret;
543	u8 *buf = val;
544
545	ret = rv3032_enter_eerd(rv3032, &eerd);
546	if (ret)
547		return ret;
548
549	for (i = 0; i < bytes; i++) {
550		ret = regmap_write(rv3032->regmap, RV3032_EEPROM_ADDR,
551				   RV3032_EEPROM_USER + offset + i);
552		if (ret)
553			goto exit_eerd;
554
555		ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD,
556				   RV3032_EEPROM_CMD_READ);
557		if (ret)
558			goto exit_eerd;
559
560		ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
561					       !(status & RV3032_TLSB_EEBUSY),
562					       RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
563		if (ret)
564			goto exit_eerd;
565
566		ret = regmap_read(rv3032->regmap, RV3032_EEPROM_DATA, &data);
567		if (ret)
568			goto exit_eerd;
569		buf[i] = data;
570	}
571
572exit_eerd:
573	rv3032_exit_eerd(rv3032, eerd);
574
575	return ret;
576}
577
578static int rv3032_trickle_charger_setup(struct device *dev, struct rv3032_data *rv3032)
579{
580	u32 val, ohms, voltage;
581	int i;
582
583	val = FIELD_PREP(RV3032_PMU_TCM, 1) | FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_DSM);
584	if (!device_property_read_u32(dev, "trickle-voltage-millivolt", &voltage)) {
585		for (i = 0; i < ARRAY_SIZE(rv3032_trickle_voltages); i++)
586			if (voltage == rv3032_trickle_voltages[i])
587				break;
588		if (i < ARRAY_SIZE(rv3032_trickle_voltages))
589			val = FIELD_PREP(RV3032_PMU_TCM, i) |
590			      FIELD_PREP(RV3032_PMU_BSM, RV3032_PMU_BSM_LSM);
591	}
592
593	if (device_property_read_u32(dev, "trickle-resistor-ohms", &ohms))
594		return 0;
595
596	for (i = 0; i < ARRAY_SIZE(rv3032_trickle_resistors); i++)
597		if (ohms == rv3032_trickle_resistors[i])
598			break;
599
600	if (i >= ARRAY_SIZE(rv3032_trickle_resistors)) {
601		dev_warn(dev, "invalid trickle resistor value\n");
602
603		return 0;
604	}
605
606	rv3032->trickle_charger_set = true;
607
608	return rv3032_update_cfg(rv3032, RV3032_PMU,
609				 RV3032_PMU_TCR | RV3032_PMU_TCM | RV3032_PMU_BSM,
610				 val | FIELD_PREP(RV3032_PMU_TCR, i));
611}
612
613#ifdef CONFIG_COMMON_CLK
614#define clkout_hw_to_rv3032(hw) container_of(hw, struct rv3032_data, clkout_hw)
615
616static int clkout_xtal_rates[] = {
617	32768,
618	1024,
619	64,
620	1,
621};
622
623#define RV3032_HFD_STEP 8192
624
625static unsigned long rv3032_clkout_recalc_rate(struct clk_hw *hw,
626					       unsigned long parent_rate)
627{
628	int clkout, ret;
629	struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
630
631	ret = regmap_read(rv3032->regmap, RV3032_CLKOUT2, &clkout);
632	if (ret < 0)
633		return 0;
634
635	if (clkout & RV3032_CLKOUT2_OS) {
636		unsigned long rate = FIELD_GET(RV3032_CLKOUT2_HFD_MSK, clkout) << 8;
637
638		ret = regmap_read(rv3032->regmap, RV3032_CLKOUT1, &clkout);
639		if (ret < 0)
640			return 0;
641
642		rate += clkout + 1;
643
644		return rate * RV3032_HFD_STEP;
645	}
646
647	return clkout_xtal_rates[FIELD_GET(RV3032_CLKOUT2_FD_MSK, clkout)];
648}
649
650static long rv3032_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
651				     unsigned long *prate)
652{
653	int i, hfd;
654
655	if (rate < RV3032_HFD_STEP)
656		for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++)
657			if (clkout_xtal_rates[i] <= rate)
658				return clkout_xtal_rates[i];
659
660	hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
661
662	return RV3032_HFD_STEP * clamp(hfd, 0, 8192);
663}
664
665static int rv3032_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
666				  unsigned long parent_rate)
667{
668	struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
669	u32 status, eerd;
670	int i, hfd, ret;
671
672	for (i = 0; i < ARRAY_SIZE(clkout_xtal_rates); i++) {
673		if (clkout_xtal_rates[i] == rate) {
674			return rv3032_update_cfg(rv3032, RV3032_CLKOUT2, 0xff,
675						 FIELD_PREP(RV3032_CLKOUT2_FD_MSK, i));
676		}
677	}
678
679	hfd = DIV_ROUND_CLOSEST(rate, RV3032_HFD_STEP);
680	hfd = clamp(hfd, 1, 8192) - 1;
681
682	ret = rv3032_enter_eerd(rv3032, &eerd);
683	if (ret)
684		return ret;
685
686	ret = regmap_write(rv3032->regmap, RV3032_CLKOUT1, hfd & 0xff);
687	if (ret)
688		goto exit_eerd;
689
690	ret = regmap_write(rv3032->regmap, RV3032_CLKOUT2, RV3032_CLKOUT2_OS |
691			    FIELD_PREP(RV3032_CLKOUT2_HFD_MSK, hfd >> 8));
692	if (ret)
693		goto exit_eerd;
694
695	ret = regmap_write(rv3032->regmap, RV3032_EEPROM_CMD, RV3032_EEPROM_CMD_UPDATE);
696	if (ret)
697		goto exit_eerd;
698
699	usleep_range(46000, RV3032_EEBUSY_TIMEOUT);
700
701	ret = regmap_read_poll_timeout(rv3032->regmap, RV3032_TLSB, status,
702				       !(status & RV3032_TLSB_EEBUSY),
703				       RV3032_EEBUSY_POLL, RV3032_EEBUSY_TIMEOUT);
704
705exit_eerd:
706	rv3032_exit_eerd(rv3032, eerd);
707
708	return ret;
709}
710
711static int rv3032_clkout_prepare(struct clk_hw *hw)
712{
713	struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
714
715	return rv3032_update_cfg(rv3032, RV3032_PMU, RV3032_PMU_NCLKE, 0);
716}
717
718static void rv3032_clkout_unprepare(struct clk_hw *hw)
719{
720	struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
721
722	rv3032_update_cfg(rv3032, RV3032_PMU, RV3032_PMU_NCLKE, RV3032_PMU_NCLKE);
723}
724
725static int rv3032_clkout_is_prepared(struct clk_hw *hw)
726{
727	int val, ret;
728	struct rv3032_data *rv3032 = clkout_hw_to_rv3032(hw);
729
730	ret = regmap_read(rv3032->regmap, RV3032_PMU, &val);
731	if (ret < 0)
732		return ret;
733
734	return !(val & RV3032_PMU_NCLKE);
735}
736
737static const struct clk_ops rv3032_clkout_ops = {
738	.prepare = rv3032_clkout_prepare,
739	.unprepare = rv3032_clkout_unprepare,
740	.is_prepared = rv3032_clkout_is_prepared,
741	.recalc_rate = rv3032_clkout_recalc_rate,
742	.round_rate = rv3032_clkout_round_rate,
743	.set_rate = rv3032_clkout_set_rate,
744};
745
746static int rv3032_clkout_register_clk(struct rv3032_data *rv3032,
747				      struct i2c_client *client)
748{
749	int ret;
750	struct clk *clk;
751	struct clk_init_data init;
752	struct device_node *node = client->dev.of_node;
753
754	ret = regmap_update_bits(rv3032->regmap, RV3032_TLSB, RV3032_TLSB_CLKF, 0);
755	if (ret < 0)
756		return ret;
757
758	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL2, RV3032_CTRL2_CLKIE, 0);
759	if (ret < 0)
760		return ret;
761
762	ret = regmap_write(rv3032->regmap, RV3032_CLK_IRQ, 0);
763	if (ret < 0)
764		return ret;
765
766	init.name = "rv3032-clkout";
767	init.ops = &rv3032_clkout_ops;
768	init.flags = 0;
769	init.parent_names = NULL;
770	init.num_parents = 0;
771	rv3032->clkout_hw.init = &init;
772
773	of_property_read_string(node, "clock-output-names", &init.name);
774
775	clk = devm_clk_register(&client->dev, &rv3032->clkout_hw);
776	if (!IS_ERR(clk))
777		of_clk_add_provider(node, of_clk_src_simple_get, clk);
778
779	return 0;
780}
781#endif
782
783static int rv3032_hwmon_read_temp(struct device *dev, long *mC)
784{
785	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
786	u8 buf[2];
787	int temp, prev = 0;
788	int ret;
789
790	ret = regmap_bulk_read(rv3032->regmap, RV3032_TLSB, buf, sizeof(buf));
791	if (ret)
792		return ret;
793
794	temp = sign_extend32(buf[1], 7) << 4;
795	temp |= FIELD_GET(RV3032_TLSB_TEMP, buf[0]);
796
797	/* No blocking or shadowing on RV3032_TLSB and RV3032_TMSB */
798	do {
799		prev = temp;
800
801		ret = regmap_bulk_read(rv3032->regmap, RV3032_TLSB, buf, sizeof(buf));
802		if (ret)
803			return ret;
804
805		temp = sign_extend32(buf[1], 7) << 4;
806		temp |= FIELD_GET(RV3032_TLSB_TEMP, buf[0]);
807	} while (temp != prev);
808
809	*mC = (temp * 1000) / 16;
810
811	return 0;
812}
813
814static umode_t rv3032_hwmon_is_visible(const void *data, enum hwmon_sensor_types type,
815				       u32 attr, int channel)
816{
817	if (type != hwmon_temp)
818		return 0;
819
820	switch (attr) {
821	case hwmon_temp_input:
822		return 0444;
823	default:
824		return 0;
825	}
826}
827
828static int rv3032_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
829			     u32 attr, int channel, long *temp)
830{
831	int err;
832
833	switch (attr) {
834	case hwmon_temp_input:
835		err = rv3032_hwmon_read_temp(dev, temp);
836		break;
837	default:
838		err = -EOPNOTSUPP;
839		break;
840	}
841
842	return err;
843}
844
845static const struct hwmon_channel_info * const rv3032_hwmon_info[] = {
846	HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
847	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MAX_HYST),
848	NULL
849};
850
851static const struct hwmon_ops rv3032_hwmon_hwmon_ops = {
852	.is_visible = rv3032_hwmon_is_visible,
853	.read = rv3032_hwmon_read,
854};
855
856static const struct hwmon_chip_info rv3032_hwmon_chip_info = {
857	.ops = &rv3032_hwmon_hwmon_ops,
858	.info = rv3032_hwmon_info,
859};
860
861static void rv3032_hwmon_register(struct device *dev)
862{
863	struct rv3032_data *rv3032 = dev_get_drvdata(dev);
864
865	if (!IS_REACHABLE(CONFIG_HWMON))
866		return;
867
868	devm_hwmon_device_register_with_info(dev, "rv3032", rv3032, &rv3032_hwmon_chip_info, NULL);
869}
870
871static const struct rtc_class_ops rv3032_rtc_ops = {
872	.read_time = rv3032_get_time,
873	.set_time = rv3032_set_time,
874	.read_offset = rv3032_read_offset,
875	.set_offset = rv3032_set_offset,
876	.ioctl = rv3032_ioctl,
877	.read_alarm = rv3032_get_alarm,
878	.set_alarm = rv3032_set_alarm,
879	.alarm_irq_enable = rv3032_alarm_irq_enable,
880	.param_get = rv3032_param_get,
881	.param_set = rv3032_param_set,
882};
883
884static const struct regmap_config regmap_config = {
885	.reg_bits = 8,
886	.val_bits = 8,
887	.max_register = 0xCA,
888};
889
890static int rv3032_probe(struct i2c_client *client)
891{
892	struct rv3032_data *rv3032;
893	int ret, status;
894	struct nvmem_config nvmem_cfg = {
895		.name = "rv3032_nvram",
896		.word_size = 1,
897		.stride = 1,
898		.size = 16,
899		.type = NVMEM_TYPE_BATTERY_BACKED,
900		.reg_read = rv3032_nvram_read,
901		.reg_write = rv3032_nvram_write,
902	};
903	struct nvmem_config eeprom_cfg = {
904		.name = "rv3032_eeprom",
905		.word_size = 1,
906		.stride = 1,
907		.size = 32,
908		.type = NVMEM_TYPE_EEPROM,
909		.reg_read = rv3032_eeprom_read,
910		.reg_write = rv3032_eeprom_write,
911	};
912
913	rv3032 = devm_kzalloc(&client->dev, sizeof(struct rv3032_data),
914			      GFP_KERNEL);
915	if (!rv3032)
916		return -ENOMEM;
917
918	rv3032->regmap = devm_regmap_init_i2c(client, &regmap_config);
919	if (IS_ERR(rv3032->regmap))
920		return PTR_ERR(rv3032->regmap);
921
922	i2c_set_clientdata(client, rv3032);
923
924	ret = regmap_read(rv3032->regmap, RV3032_STATUS, &status);
925	if (ret < 0)
926		return ret;
927
928	rv3032->rtc = devm_rtc_allocate_device(&client->dev);
929	if (IS_ERR(rv3032->rtc))
930		return PTR_ERR(rv3032->rtc);
931
932	if (client->irq > 0) {
933		unsigned long irqflags = IRQF_TRIGGER_LOW;
934
935		if (dev_fwnode(&client->dev))
936			irqflags = 0;
937
938		ret = devm_request_threaded_irq(&client->dev, client->irq,
939						NULL, rv3032_handle_irq,
940						irqflags | IRQF_ONESHOT,
941						"rv3032", rv3032);
942		if (ret) {
943			dev_warn(&client->dev, "unable to request IRQ, alarms disabled\n");
944			client->irq = 0;
945		}
946	}
947	if (!client->irq)
948		clear_bit(RTC_FEATURE_ALARM, rv3032->rtc->features);
949
950	ret = regmap_update_bits(rv3032->regmap, RV3032_CTRL1,
951				 RV3032_CTRL1_WADA, RV3032_CTRL1_WADA);
952	if (ret)
953		return ret;
954
955	rv3032_trickle_charger_setup(&client->dev, rv3032);
956
957	set_bit(RTC_FEATURE_BACKUP_SWITCH_MODE, rv3032->rtc->features);
958	set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rv3032->rtc->features);
959
960	rv3032->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
961	rv3032->rtc->range_max = RTC_TIMESTAMP_END_2099;
962	rv3032->rtc->ops = &rv3032_rtc_ops;
963	ret = devm_rtc_register_device(rv3032->rtc);
964	if (ret)
965		return ret;
966
967	nvmem_cfg.priv = rv3032->regmap;
968	devm_rtc_nvmem_register(rv3032->rtc, &nvmem_cfg);
969	eeprom_cfg.priv = rv3032;
970	devm_rtc_nvmem_register(rv3032->rtc, &eeprom_cfg);
971
972	rv3032->rtc->max_user_freq = 1;
973
974#ifdef CONFIG_COMMON_CLK
975	rv3032_clkout_register_clk(rv3032, client);
976#endif
977
978	rv3032_hwmon_register(&client->dev);
979
980	return 0;
981}
982
983static const struct acpi_device_id rv3032_i2c_acpi_match[] = {
984	{ "MCRY3032" },
985	{ }
986};
987MODULE_DEVICE_TABLE(acpi, rv3032_i2c_acpi_match);
988
989static const __maybe_unused struct of_device_id rv3032_of_match[] = {
990	{ .compatible = "microcrystal,rv3032", },
991	{ }
992};
993MODULE_DEVICE_TABLE(of, rv3032_of_match);
994
995static struct i2c_driver rv3032_driver = {
996	.driver = {
997		.name = "rtc-rv3032",
998		.acpi_match_table = rv3032_i2c_acpi_match,
999		.of_match_table = of_match_ptr(rv3032_of_match),
1000	},
1001	.probe		= rv3032_probe,
1002};
1003module_i2c_driver(rv3032_driver);
1004
1005MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
1006MODULE_DESCRIPTION("Micro Crystal RV3032 RTC driver");
1007MODULE_LICENSE("GPL v2");
1008