Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * A driver for the I2C members of the Abracon AB x8xx RTC family,
  4 * and compatible: AB 1805 and AB 0805
  5 *
  6 * Copyright 2014-2015 Macq S.A.
  7 *
  8 * Author: Philippe De Muyter <phdm@macqel.be>
  9 * Author: Alexandre Belloni <alexandre.belloni@bootlin.com>
 10 *
 11 */
 12
 13#include <linux/bcd.h>
 14#include <linux/i2c.h>
 15#include <linux/kstrtox.h>
 16#include <linux/module.h>
 17#include <linux/of_device.h>
 18#include <linux/rtc.h>
 19#include <linux/watchdog.h>
 20
 21#define ABX8XX_REG_HTH		0x00
 22#define ABX8XX_REG_SC		0x01
 23#define ABX8XX_REG_MN		0x02
 24#define ABX8XX_REG_HR		0x03
 25#define ABX8XX_REG_DA		0x04
 26#define ABX8XX_REG_MO		0x05
 27#define ABX8XX_REG_YR		0x06
 28#define ABX8XX_REG_WD		0x07
 29
 30#define ABX8XX_REG_AHTH		0x08
 31#define ABX8XX_REG_ASC		0x09
 32#define ABX8XX_REG_AMN		0x0a
 33#define ABX8XX_REG_AHR		0x0b
 34#define ABX8XX_REG_ADA		0x0c
 35#define ABX8XX_REG_AMO		0x0d
 36#define ABX8XX_REG_AWD		0x0e
 37
 38#define ABX8XX_REG_STATUS	0x0f
 39#define ABX8XX_STATUS_AF	BIT(2)
 40#define ABX8XX_STATUS_BLF	BIT(4)
 41#define ABX8XX_STATUS_WDT	BIT(6)
 42
 43#define ABX8XX_REG_CTRL1	0x10
 44#define ABX8XX_CTRL_WRITE	BIT(0)
 45#define ABX8XX_CTRL_ARST	BIT(2)
 46#define ABX8XX_CTRL_12_24	BIT(6)
 47
 48#define ABX8XX_REG_CTRL2	0x11
 49#define ABX8XX_CTRL2_RSVD	BIT(5)
 50
 51#define ABX8XX_REG_IRQ		0x12
 52#define ABX8XX_IRQ_AIE		BIT(2)
 53#define ABX8XX_IRQ_IM_1_4	(0x3 << 5)
 54
 55#define ABX8XX_REG_CD_TIMER_CTL	0x18
 56
 57#define ABX8XX_REG_OSC		0x1c
 58#define ABX8XX_OSC_FOS		BIT(3)
 59#define ABX8XX_OSC_BOS		BIT(4)
 60#define ABX8XX_OSC_ACAL_512	BIT(5)
 61#define ABX8XX_OSC_ACAL_1024	BIT(6)
 62
 63#define ABX8XX_OSC_OSEL		BIT(7)
 64
 65#define ABX8XX_REG_OSS		0x1d
 66#define ABX8XX_OSS_OF		BIT(1)
 67#define ABX8XX_OSS_OMODE	BIT(4)
 68
 69#define ABX8XX_REG_WDT		0x1b
 70#define ABX8XX_WDT_WDS		BIT(7)
 71#define ABX8XX_WDT_BMB_MASK	0x7c
 72#define ABX8XX_WDT_BMB_SHIFT	2
 73#define ABX8XX_WDT_MAX_TIME	(ABX8XX_WDT_BMB_MASK >> ABX8XX_WDT_BMB_SHIFT)
 74#define ABX8XX_WDT_WRB_MASK	0x03
 75#define ABX8XX_WDT_WRB_1HZ	0x02
 76
 77#define ABX8XX_REG_CFG_KEY	0x1f
 78#define ABX8XX_CFG_KEY_OSC	0xa1
 79#define ABX8XX_CFG_KEY_MISC	0x9d
 80
 81#define ABX8XX_REG_ID0		0x28
 82
 83#define ABX8XX_REG_OUT_CTRL	0x30
 84#define ABX8XX_OUT_CTRL_EXDS	BIT(4)
 85
 86#define ABX8XX_REG_TRICKLE	0x20
 87#define ABX8XX_TRICKLE_CHARGE_ENABLE	0xa0
 88#define ABX8XX_TRICKLE_STANDARD_DIODE	0x8
 89#define ABX8XX_TRICKLE_SCHOTTKY_DIODE	0x4
 90
 91static u8 trickle_resistors[] = {0, 3, 6, 11};
 92
 93enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,
 94	AB1801, AB1803, AB1804, AB1805, RV1805, ABX80X};
 95
 96struct abx80x_cap {
 97	u16 pn;
 98	bool has_tc;
 99	bool has_wdog;
100};
101
102static struct abx80x_cap abx80x_caps[] = {
103	[AB0801] = {.pn = 0x0801},
104	[AB0803] = {.pn = 0x0803},
105	[AB0804] = {.pn = 0x0804, .has_tc = true, .has_wdog = true},
106	[AB0805] = {.pn = 0x0805, .has_tc = true, .has_wdog = true},
107	[AB1801] = {.pn = 0x1801},
108	[AB1803] = {.pn = 0x1803},
109	[AB1804] = {.pn = 0x1804, .has_tc = true, .has_wdog = true},
110	[AB1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},
111	[RV1805] = {.pn = 0x1805, .has_tc = true, .has_wdog = true},
112	[ABX80X] = {.pn = 0}
113};
114
115struct abx80x_priv {
116	struct rtc_device *rtc;
117	struct i2c_client *client;
118	struct watchdog_device wdog;
119};
120
121static int abx80x_write_config_key(struct i2c_client *client, u8 key)
122{
123	if (i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY, key) < 0) {
124		dev_err(&client->dev, "Unable to write configuration key\n");
125		return -EIO;
126	}
127
128	return 0;
129}
130
131static int abx80x_is_rc_mode(struct i2c_client *client)
132{
133	int flags = 0;
134
135	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
136	if (flags < 0) {
137		dev_err(&client->dev,
138			"Failed to read autocalibration attribute\n");
139		return flags;
140	}
141
142	return (flags & ABX8XX_OSS_OMODE) ? 1 : 0;
143}
144
145static int abx80x_enable_trickle_charger(struct i2c_client *client,
146					 u8 trickle_cfg)
147{
148	int err;
149
150	/*
151	 * Write the configuration key register to enable access to the Trickle
152	 * register
153	 */
154	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)
155		return -EIO;
156
157	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,
158					ABX8XX_TRICKLE_CHARGE_ENABLE |
159					trickle_cfg);
160	if (err < 0) {
161		dev_err(&client->dev, "Unable to write trickle register\n");
162		return -EIO;
163	}
164
165	return 0;
166}
167
168static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
169{
170	struct i2c_client *client = to_i2c_client(dev);
171	unsigned char buf[8];
172	int err, flags, rc_mode = 0;
173
174	/* Read the Oscillator Failure only in XT mode */
175	rc_mode = abx80x_is_rc_mode(client);
176	if (rc_mode < 0)
177		return rc_mode;
178
179	if (!rc_mode) {
180		flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
181		if (flags < 0)
182			return flags;
183
184		if (flags & ABX8XX_OSS_OF) {
185			dev_err(dev, "Oscillator failure, data is invalid.\n");
186			return -EINVAL;
187		}
188	}
189
190	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,
191					    sizeof(buf), buf);
192	if (err < 0) {
193		dev_err(&client->dev, "Unable to read date\n");
194		return -EIO;
195	}
196
197	tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);
198	tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);
199	tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);
200	tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;
201	tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);
202	tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;
203	tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;
204
205	return 0;
206}
207
208static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
209{
210	struct i2c_client *client = to_i2c_client(dev);
211	unsigned char buf[8];
212	int err, flags;
213
214	if (tm->tm_year < 100)
215		return -EINVAL;
216
217	buf[ABX8XX_REG_HTH] = 0;
218	buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);
219	buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);
220	buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);
221	buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);
222	buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);
223	buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);
224	buf[ABX8XX_REG_WD] = tm->tm_wday;
225
226	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,
227					     sizeof(buf), buf);
228	if (err < 0) {
229		dev_err(&client->dev, "Unable to write to date registers\n");
230		return -EIO;
231	}
232
233	/* Clear the OF bit of Oscillator Status Register */
234	flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
235	if (flags < 0)
236		return flags;
237
238	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS,
239					flags & ~ABX8XX_OSS_OF);
240	if (err < 0) {
241		dev_err(&client->dev, "Unable to write oscillator status register\n");
242		return err;
243	}
244
245	return 0;
246}
247
248static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
249{
250	struct i2c_client *client = dev_id;
251	struct abx80x_priv *priv = i2c_get_clientdata(client);
252	struct rtc_device *rtc = priv->rtc;
253	int status;
254
255	status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
256	if (status < 0)
257		return IRQ_NONE;
258
259	if (status & ABX8XX_STATUS_AF)
260		rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);
261
262	/*
263	 * It is unclear if we'll get an interrupt before the external
264	 * reset kicks in.
265	 */
266	if (status & ABX8XX_STATUS_WDT)
267		dev_alert(&client->dev, "watchdog timeout interrupt.\n");
268
269	i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
270
271	return IRQ_HANDLED;
272}
273
274static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
275{
276	struct i2c_client *client = to_i2c_client(dev);
277	unsigned char buf[7];
278
279	int irq_mask, err;
280
281	if (client->irq <= 0)
282		return -EINVAL;
283
284	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
285					    sizeof(buf), buf);
286	if (err)
287		return err;
288
289	irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
290	if (irq_mask < 0)
291		return irq_mask;
292
293	t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
294	t->time.tm_min = bcd2bin(buf[1] & 0x7F);
295	t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
296	t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
297	t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
298	t->time.tm_wday = buf[5] & 0x7;
299
300	t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
301	t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;
302
303	return err;
304}
305
306static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
307{
308	struct i2c_client *client = to_i2c_client(dev);
309	u8 alarm[6];
310	int err;
311
312	if (client->irq <= 0)
313		return -EINVAL;
314
315	alarm[0] = 0x0;
316	alarm[1] = bin2bcd(t->time.tm_sec);
317	alarm[2] = bin2bcd(t->time.tm_min);
318	alarm[3] = bin2bcd(t->time.tm_hour);
319	alarm[4] = bin2bcd(t->time.tm_mday);
320	alarm[5] = bin2bcd(t->time.tm_mon + 1);
321
322	err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
323					     sizeof(alarm), alarm);
324	if (err < 0) {
325		dev_err(&client->dev, "Unable to write alarm registers\n");
326		return -EIO;
327	}
328
329	if (t->enabled) {
330		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
331						(ABX8XX_IRQ_IM_1_4 |
332						 ABX8XX_IRQ_AIE));
333		if (err)
334			return err;
335	}
336
337	return 0;
338}
339
340static int abx80x_rtc_set_autocalibration(struct device *dev,
341					  int autocalibration)
342{
343	struct i2c_client *client = to_i2c_client(dev);
344	int retval, flags = 0;
345
346	if ((autocalibration != 0) && (autocalibration != 1024) &&
347	    (autocalibration != 512)) {
348		dev_err(dev, "autocalibration value outside permitted range\n");
349		return -EINVAL;
350	}
351
352	flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
353	if (flags < 0)
354		return flags;
355
356	if (autocalibration == 0) {
357		flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024);
358	} else if (autocalibration == 1024) {
359		/* 1024 autocalibration is 0x10 */
360		flags |= ABX8XX_OSC_ACAL_1024;
361		flags &= ~(ABX8XX_OSC_ACAL_512);
362	} else {
363		/* 512 autocalibration is 0x11 */
364		flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512);
365	}
366
367	/* Unlock write access to Oscillator Control Register */
368	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)
369		return -EIO;
370
371	retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
372
373	return retval;
374}
375
376static int abx80x_rtc_get_autocalibration(struct device *dev)
377{
378	struct i2c_client *client = to_i2c_client(dev);
379	int flags = 0, autocalibration;
380
381	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
382	if (flags < 0)
383		return flags;
384
385	if (flags & ABX8XX_OSC_ACAL_512)
386		autocalibration = 512;
387	else if (flags & ABX8XX_OSC_ACAL_1024)
388		autocalibration = 1024;
389	else
390		autocalibration = 0;
391
392	return autocalibration;
393}
394
395static ssize_t autocalibration_store(struct device *dev,
396				     struct device_attribute *attr,
397				     const char *buf, size_t count)
398{
399	int retval;
400	unsigned long autocalibration = 0;
401
402	retval = kstrtoul(buf, 10, &autocalibration);
403	if (retval < 0) {
404		dev_err(dev, "Failed to store RTC autocalibration attribute\n");
405		return -EINVAL;
406	}
407
408	retval = abx80x_rtc_set_autocalibration(dev->parent, autocalibration);
409
410	return retval ? retval : count;
411}
412
413static ssize_t autocalibration_show(struct device *dev,
414				    struct device_attribute *attr, char *buf)
415{
416	int autocalibration = 0;
417
418	autocalibration = abx80x_rtc_get_autocalibration(dev->parent);
419	if (autocalibration < 0) {
420		dev_err(dev, "Failed to read RTC autocalibration\n");
421		sprintf(buf, "0\n");
422		return autocalibration;
423	}
424
425	return sprintf(buf, "%d\n", autocalibration);
426}
427
428static DEVICE_ATTR_RW(autocalibration);
429
430static ssize_t oscillator_store(struct device *dev,
431				struct device_attribute *attr,
432				const char *buf, size_t count)
433{
434	struct i2c_client *client = to_i2c_client(dev->parent);
435	int retval, flags, rc_mode = 0;
436
437	if (strncmp(buf, "rc", 2) == 0) {
438		rc_mode = 1;
439	} else if (strncmp(buf, "xtal", 4) == 0) {
440		rc_mode = 0;
441	} else {
442		dev_err(dev, "Oscillator selection value outside permitted ones\n");
443		return -EINVAL;
444	}
445
446	flags =  i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
447	if (flags < 0)
448		return flags;
449
450	if (rc_mode == 0)
451		flags &= ~(ABX8XX_OSC_OSEL);
452	else
453		flags |= (ABX8XX_OSC_OSEL);
454
455	/* Unlock write access on Oscillator Control register */
456	if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_OSC) < 0)
457		return -EIO;
458
459	retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
460	if (retval < 0) {
461		dev_err(dev, "Failed to write Oscillator Control register\n");
462		return retval;
463	}
464
465	return retval ? retval : count;
466}
467
468static ssize_t oscillator_show(struct device *dev,
469			       struct device_attribute *attr, char *buf)
470{
471	int rc_mode = 0;
472	struct i2c_client *client = to_i2c_client(dev->parent);
473
474	rc_mode = abx80x_is_rc_mode(client);
475
476	if (rc_mode < 0) {
477		dev_err(dev, "Failed to read RTC oscillator selection\n");
478		sprintf(buf, "\n");
479		return rc_mode;
480	}
481
482	if (rc_mode)
483		return sprintf(buf, "rc\n");
484	else
485		return sprintf(buf, "xtal\n");
486}
487
488static DEVICE_ATTR_RW(oscillator);
489
490static struct attribute *rtc_calib_attrs[] = {
491	&dev_attr_autocalibration.attr,
492	&dev_attr_oscillator.attr,
493	NULL,
494};
495
496static const struct attribute_group rtc_calib_attr_group = {
497	.attrs		= rtc_calib_attrs,
498};
499
500static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
501{
502	struct i2c_client *client = to_i2c_client(dev);
503	int err;
504
505	if (enabled)
506		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
507						(ABX8XX_IRQ_IM_1_4 |
508						 ABX8XX_IRQ_AIE));
509	else
510		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
511						ABX8XX_IRQ_IM_1_4);
512	return err;
513}
514
515static int abx80x_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
516{
517	struct i2c_client *client = to_i2c_client(dev);
518	int status, tmp;
519
520	switch (cmd) {
521	case RTC_VL_READ:
522		status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
523		if (status < 0)
524			return status;
525
526		tmp = status & ABX8XX_STATUS_BLF ? RTC_VL_BACKUP_LOW : 0;
527
528		return put_user(tmp, (unsigned int __user *)arg);
529
530	case RTC_VL_CLR:
531		status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
532		if (status < 0)
533			return status;
534
535		status &= ~ABX8XX_STATUS_BLF;
536
537		tmp = i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
538		if (tmp < 0)
539			return tmp;
540
541		return 0;
542
543	default:
544		return -ENOIOCTLCMD;
545	}
546}
547
548static const struct rtc_class_ops abx80x_rtc_ops = {
549	.read_time	= abx80x_rtc_read_time,
550	.set_time	= abx80x_rtc_set_time,
551	.read_alarm	= abx80x_read_alarm,
552	.set_alarm	= abx80x_set_alarm,
553	.alarm_irq_enable = abx80x_alarm_irq_enable,
554	.ioctl		= abx80x_ioctl,
555};
556
557static int abx80x_dt_trickle_cfg(struct i2c_client *client)
558{
559	struct device_node *np = client->dev.of_node;
560	const char *diode;
561	int trickle_cfg = 0;
562	int i, ret;
563	u32 tmp;
564
565	ret = of_property_read_string(np, "abracon,tc-diode", &diode);
566	if (ret)
567		return ret;
568
569	if (!strcmp(diode, "standard")) {
570		trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE;
571	} else if (!strcmp(diode, "schottky")) {
572		trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE;
573	} else {
574		dev_dbg(&client->dev, "Invalid tc-diode value: %s\n", diode);
575		return -EINVAL;
576	}
577
578	ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);
579	if (ret)
580		return ret;
581
582	for (i = 0; i < sizeof(trickle_resistors); i++)
583		if (trickle_resistors[i] == tmp)
584			break;
585
586	if (i == sizeof(trickle_resistors)) {
587		dev_dbg(&client->dev, "Invalid tc-resistor value: %u\n", tmp);
588		return -EINVAL;
589	}
590
591	return (trickle_cfg | i);
592}
593
594#ifdef CONFIG_WATCHDOG
595
596static inline u8 timeout_bits(unsigned int timeout)
597{
598	return ((timeout << ABX8XX_WDT_BMB_SHIFT) & ABX8XX_WDT_BMB_MASK) |
599		 ABX8XX_WDT_WRB_1HZ;
600}
601
602static int __abx80x_wdog_set_timeout(struct watchdog_device *wdog,
603				     unsigned int timeout)
604{
605	struct abx80x_priv *priv = watchdog_get_drvdata(wdog);
606	u8 val = ABX8XX_WDT_WDS | timeout_bits(timeout);
607
608	/*
609	 * Writing any timeout to the WDT register resets the watchdog timer.
610	 * Writing 0 disables it.
611	 */
612	return i2c_smbus_write_byte_data(priv->client, ABX8XX_REG_WDT, val);
613}
614
615static int abx80x_wdog_set_timeout(struct watchdog_device *wdog,
616				   unsigned int new_timeout)
617{
618	int err = 0;
619
620	if (watchdog_hw_running(wdog))
621		err = __abx80x_wdog_set_timeout(wdog, new_timeout);
622
623	if (err == 0)
624		wdog->timeout = new_timeout;
625
626	return err;
627}
628
629static int abx80x_wdog_ping(struct watchdog_device *wdog)
630{
631	return __abx80x_wdog_set_timeout(wdog, wdog->timeout);
632}
633
634static int abx80x_wdog_start(struct watchdog_device *wdog)
635{
636	return __abx80x_wdog_set_timeout(wdog, wdog->timeout);
637}
638
639static int abx80x_wdog_stop(struct watchdog_device *wdog)
640{
641	return __abx80x_wdog_set_timeout(wdog, 0);
642}
643
644static const struct watchdog_info abx80x_wdog_info = {
645	.identity = "abx80x watchdog",
646	.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
647};
648
649static const struct watchdog_ops abx80x_wdog_ops = {
650	.owner = THIS_MODULE,
651	.start = abx80x_wdog_start,
652	.stop = abx80x_wdog_stop,
653	.ping = abx80x_wdog_ping,
654	.set_timeout = abx80x_wdog_set_timeout,
655};
656
657static int abx80x_setup_watchdog(struct abx80x_priv *priv)
658{
659	priv->wdog.parent = &priv->client->dev;
660	priv->wdog.ops = &abx80x_wdog_ops;
661	priv->wdog.info = &abx80x_wdog_info;
662	priv->wdog.min_timeout = 1;
663	priv->wdog.max_timeout = ABX8XX_WDT_MAX_TIME;
664	priv->wdog.timeout = ABX8XX_WDT_MAX_TIME;
665
666	watchdog_set_drvdata(&priv->wdog, priv);
667
668	return devm_watchdog_register_device(&priv->client->dev, &priv->wdog);
669}
670#else
671static int abx80x_setup_watchdog(struct abx80x_priv *priv)
672{
673	return 0;
674}
675#endif
676
677static const struct i2c_device_id abx80x_id[] = {
678	{ "abx80x", ABX80X },
679	{ "ab0801", AB0801 },
680	{ "ab0803", AB0803 },
681	{ "ab0804", AB0804 },
682	{ "ab0805", AB0805 },
683	{ "ab1801", AB1801 },
684	{ "ab1803", AB1803 },
685	{ "ab1804", AB1804 },
686	{ "ab1805", AB1805 },
687	{ "rv1805", RV1805 },
688	{ }
689};
690MODULE_DEVICE_TABLE(i2c, abx80x_id);
691
692static int abx80x_probe(struct i2c_client *client)
693{
694	struct device_node *np = client->dev.of_node;
695	struct abx80x_priv *priv;
696	int i, data, err, trickle_cfg = -EINVAL;
697	char buf[7];
698	const struct i2c_device_id *id = i2c_match_id(abx80x_id, client);
699	unsigned int part = id->driver_data;
700	unsigned int partnumber;
701	unsigned int majrev, minrev;
702	unsigned int lot;
703	unsigned int wafer;
704	unsigned int uid;
705
706	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
707		return -ENODEV;
708
709	err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,
710					    sizeof(buf), buf);
711	if (err < 0) {
712		dev_err(&client->dev, "Unable to read partnumber\n");
713		return -EIO;
714	}
715
716	partnumber = (buf[0] << 8) | buf[1];
717	majrev = buf[2] >> 3;
718	minrev = buf[2] & 0x7;
719	lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];
720	uid = ((buf[4] & 0x7f) << 8) | buf[5];
721	wafer = (buf[6] & 0x7c) >> 2;
722	dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
723		 partnumber, majrev, minrev, lot, wafer, uid);
724
725	data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);
726	if (data < 0) {
727		dev_err(&client->dev, "Unable to read control register\n");
728		return -EIO;
729	}
730
731	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
732					((data & ~(ABX8XX_CTRL_12_24 |
733						   ABX8XX_CTRL_ARST)) |
734					 ABX8XX_CTRL_WRITE));
735	if (err < 0) {
736		dev_err(&client->dev, "Unable to write control register\n");
737		return -EIO;
738	}
739
740	/* Configure RV1805 specifics */
741	if (part == RV1805) {
742		/*
743		 * Avoid accidentally entering test mode. This can happen
744		 * on the RV1805 in case the reserved bit 5 in control2
745		 * register is set. RV-1805-C3 datasheet indicates that
746		 * the bit should be cleared in section 11h - Control2.
747		 */
748		data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL2);
749		if (data < 0) {
750			dev_err(&client->dev,
751				"Unable to read control2 register\n");
752			return -EIO;
753		}
754
755		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL2,
756						data & ~ABX8XX_CTRL2_RSVD);
757		if (err < 0) {
758			dev_err(&client->dev,
759				"Unable to write control2 register\n");
760			return -EIO;
761		}
762
763		/*
764		 * Avoid extra power leakage. The RV1805 uses smaller
765		 * 10pin package and the EXTI input is not present.
766		 * Disable it to avoid leakage.
767		 */
768		data = i2c_smbus_read_byte_data(client, ABX8XX_REG_OUT_CTRL);
769		if (data < 0) {
770			dev_err(&client->dev,
771				"Unable to read output control register\n");
772			return -EIO;
773		}
774
775		/*
776		 * Write the configuration key register to enable access to
777		 * the config2 register
778		 */
779		if (abx80x_write_config_key(client, ABX8XX_CFG_KEY_MISC) < 0)
780			return -EIO;
781
782		err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OUT_CTRL,
783						data | ABX8XX_OUT_CTRL_EXDS);
784		if (err < 0) {
785			dev_err(&client->dev,
786				"Unable to write output control register\n");
787			return -EIO;
788		}
789	}
790
791	/* part autodetection */
792	if (part == ABX80X) {
793		for (i = 0; abx80x_caps[i].pn; i++)
794			if (partnumber == abx80x_caps[i].pn)
795				break;
796		if (abx80x_caps[i].pn == 0) {
797			dev_err(&client->dev, "Unknown part: %04x\n",
798				partnumber);
799			return -EINVAL;
800		}
801		part = i;
802	}
803
804	if (partnumber != abx80x_caps[part].pn) {
805		dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",
806			partnumber, abx80x_caps[part].pn);
807		return -EINVAL;
808	}
809
810	if (np && abx80x_caps[part].has_tc)
811		trickle_cfg = abx80x_dt_trickle_cfg(client);
812
813	if (trickle_cfg > 0) {
814		dev_info(&client->dev, "Enabling trickle charger: %02x\n",
815			 trickle_cfg);
816		abx80x_enable_trickle_charger(client, trickle_cfg);
817	}
818
819	err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
820					BIT(2));
821	if (err)
822		return err;
823
824	priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL);
825	if (priv == NULL)
826		return -ENOMEM;
827
828	priv->rtc = devm_rtc_allocate_device(&client->dev);
829	if (IS_ERR(priv->rtc))
830		return PTR_ERR(priv->rtc);
831
832	priv->rtc->ops = &abx80x_rtc_ops;
833	priv->client = client;
834
835	i2c_set_clientdata(client, priv);
836
837	if (abx80x_caps[part].has_wdog) {
838		err = abx80x_setup_watchdog(priv);
839		if (err)
840			return err;
841	}
842
843	if (client->irq > 0) {
844		dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
845		err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
846						abx80x_handle_irq,
847						IRQF_SHARED | IRQF_ONESHOT,
848						"abx8xx",
849						client);
850		if (err) {
851			dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
852			client->irq = 0;
853		}
854	}
855
856	err = rtc_add_group(priv->rtc, &rtc_calib_attr_group);
857	if (err) {
858		dev_err(&client->dev, "Failed to create sysfs group: %d\n",
859			err);
860		return err;
861	}
862
863	return devm_rtc_register_device(priv->rtc);
864}
865
866#ifdef CONFIG_OF
867static const struct of_device_id abx80x_of_match[] = {
868	{
869		.compatible = "abracon,abx80x",
870		.data = (void *)ABX80X
871	},
872	{
873		.compatible = "abracon,ab0801",
874		.data = (void *)AB0801
875	},
876	{
877		.compatible = "abracon,ab0803",
878		.data = (void *)AB0803
879	},
880	{
881		.compatible = "abracon,ab0804",
882		.data = (void *)AB0804
883	},
884	{
885		.compatible = "abracon,ab0805",
886		.data = (void *)AB0805
887	},
888	{
889		.compatible = "abracon,ab1801",
890		.data = (void *)AB1801
891	},
892	{
893		.compatible = "abracon,ab1803",
894		.data = (void *)AB1803
895	},
896	{
897		.compatible = "abracon,ab1804",
898		.data = (void *)AB1804
899	},
900	{
901		.compatible = "abracon,ab1805",
902		.data = (void *)AB1805
903	},
904	{
905		.compatible = "microcrystal,rv1805",
906		.data = (void *)RV1805
907	},
908	{ }
909};
910MODULE_DEVICE_TABLE(of, abx80x_of_match);
911#endif
912
913static struct i2c_driver abx80x_driver = {
914	.driver		= {
915		.name	= "rtc-abx80x",
916		.of_match_table = of_match_ptr(abx80x_of_match),
917	},
918	.probe_new	= abx80x_probe,
919	.id_table	= abx80x_id,
920};
921
922module_i2c_driver(abx80x_driver);
923
924MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
925MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
926MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
927MODULE_LICENSE("GPL v2");