[linux-2.6-block.git] / drivers / rtc / rtc-pcf8523.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2012 Avionic Design GmbH
 */

#include <linux/bcd.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/rtc.h>
#include <linux/of.h>

#define DRIVER_NAME "rtc-pcf8523"

#define REG_CONTROL1 0x00
#define REG_CONTROL1_CAP_SEL (1 << 7)
#define REG_CONTROL1_STOP    (1 << 5)

#define REG_CONTROL3 0x02
#define REG_CONTROL3_PM_BLD (1 << 7) /* battery low detection disabled */
#define REG_CONTROL3_PM_VDD (1 << 6) /* switch-over disabled */
#define REG_CONTROL3_PM_DSM (1 << 5) /* direct switching mode */
#define REG_CONTROL3_PM_MASK 0xe0
#define REG_CONTROL3_BLF (1 << 2) /* battery low bit, read-only */

#define REG_SECONDS  0x03
#define REG_SECONDS_OS (1 << 7)

#define REG_MINUTES  0x04
#define REG_HOURS    0x05
#define REG_DAYS     0x06
#define REG_WEEKDAYS 0x07
#define REG_MONTHS   0x08
#define REG_YEARS    0x09

#define REG_OFFSET   0x0e
#define REG_OFFSET_MODE BIT(7)

static int pcf8523_read(struct i2c_client *client, u8 reg, u8 *valuep)
{
	struct i2c_msg msgs[2];
	u8 value = 0;
	int err;

	msgs[0].addr = client->addr;
	msgs[0].flags = 0;
	msgs[0].len = sizeof(reg);
	msgs[0].buf = &reg;

	msgs[1].addr = client->addr;
	msgs[1].flags = I2C_M_RD;
	msgs[1].len = sizeof(value);
	msgs[1].buf = &value;

	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (err < 0)
		return err;

	*valuep = value;

	return 0;
}

static int pcf8523_write(struct i2c_client *client, u8 reg, u8 value)
{
	u8 buffer[2] = { reg, value };
	struct i2c_msg msg;
	int err;

	msg.addr = client->addr;
	msg.flags = 0;
	msg.len = sizeof(buffer);
	msg.buf = buffer;

	err = i2c_transfer(client->adapter, &msg, 1);
	if (err < 0)
		return err;

	return 0;
}

static int pcf8523_voltage_low(struct i2c_client *client)
{
	u8 value;
	int err;

	err = pcf8523_read(client, REG_CONTROL3, &value);
	if (err < 0)
		return err;

	return !!(value & REG_CONTROL3_BLF);
}

static int pcf8523_load_capacitance(struct i2c_client *client)
{
	u32 load;
	u8 value;
	int err;

	err = pcf8523_read(client, REG_CONTROL1, &value);
	if (err < 0)
		return err;

	load = 12500;
	of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",
			     &load);

	switch (load) {
	default:
		dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 12500",
			 load);
		fallthrough;
	case 12500:
		value |= REG_CONTROL1_CAP_SEL;
		break;
	case 7000:
		value &= ~REG_CONTROL1_CAP_SEL;
		break;
	}

	err = pcf8523_write(client, REG_CONTROL1, value);

	return err;
}

static int pcf8523_set_pm(struct i2c_client *client, u8 pm)
{
	u8 value;
	int err;

	err = pcf8523_read(client, REG_CONTROL3, &value);
	if (err < 0)
		return err;

	value = (value & ~REG_CONTROL3_PM_MASK) | pm;

	err = pcf8523_write(client, REG_CONTROL3, value);
	if (err < 0)
		return err;

	return 0;
}

static int pcf8523_stop_rtc(struct i2c_client *client)
{
	u8 value;
	int err;

	err = pcf8523_read(client, REG_CONTROL1, &value);
	if (err < 0)
		return err;

	value |= REG_CONTROL1_STOP;

	err = pcf8523_write(client, REG_CONTROL1, value);
	if (err < 0)
		return err;

	return 0;
}

static int pcf8523_start_rtc(struct i2c_client *client)
{
	u8 value;
	int err;

	err = pcf8523_read(client, REG_CONTROL1, &value);
	if (err < 0)
		return err;

	value &= ~REG_CONTROL1_STOP;

	err = pcf8523_write(client, REG_CONTROL1, value);
	if (err < 0)
		return err;

	return 0;
}

static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	u8 start = REG_SECONDS, regs[7];
	struct i2c_msg msgs[2];
	int err;

	err = pcf8523_voltage_low(client);
	if (err < 0) {
		return err;
	} else if (err > 0) {
		dev_err(dev, "low voltage detected, time is unreliable\n");
		return -EINVAL;
	}

	msgs[0].addr = client->addr;
	msgs[0].flags = 0;
	msgs[0].len = 1;
	msgs[0].buf = &start;

	msgs[1].addr = client->addr;
	msgs[1].flags = I2C_M_RD;
	msgs[1].len = sizeof(regs);
	msgs[1].buf = regs;

	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	if (err < 0)
		return err;

	if (regs[0] & REG_SECONDS_OS)
		return -EINVAL;

	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
	tm->tm_min = bcd2bin(regs[1] & 0x7f);
	tm->tm_hour = bcd2bin(regs[2] & 0x3f);
	tm->tm_mday = bcd2bin(regs[3] & 0x3f);
	tm->tm_wday = regs[4] & 0x7;
	tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1;
	tm->tm_year = bcd2bin(regs[6]) + 100;

	return 0;
}

static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm)
{
	struct i2c_client *client = to_i2c_client(dev);
	struct i2c_msg msg;
	u8 regs[8];
	int err;

	/*
	 * The hardware can only store values between 0 and 99 in it's YEAR
	 * register (with 99 overflowing to 0 on increment).
	 * After 2100-02-28 we could start interpreting the year to be in the
	 * interval [2100, 2199], but there is no path to switch in a smooth way
	 * because the chip handles YEAR=0x00 (and the out-of-spec
	 * YEAR=0xa0) as a leap year, but 2100 isn't.
	 */
	if (tm->tm_year < 100 || tm->tm_year >= 200)
		return -EINVAL;

	err = pcf8523_stop_rtc(client);
	if (err < 0)
		return err;

	regs[0] = REG_SECONDS;
	/* This will purposely overwrite REG_SECONDS_OS */
	regs[1] = bin2bcd(tm->tm_sec);
	regs[2] = bin2bcd(tm->tm_min);
	regs[3] = bin2bcd(tm->tm_hour);
	regs[4] = bin2bcd(tm->tm_mday);
	regs[5] = tm->tm_wday;
	regs[6] = bin2bcd(tm->tm_mon + 1);
	regs[7] = bin2bcd(tm->tm_year - 100);

	msg.addr = client->addr;
	msg.flags = 0;
	msg.len = sizeof(regs);
	msg.buf = regs;

	err = i2c_transfer(client->adapter, &msg, 1);
	if (err < 0) {
		/*
		 * If the time cannot be set, restart the RTC anyway. Note
		 * that errors are ignored if the RTC cannot be started so
		 * that we have a chance to propagate the original error.
		 */
		pcf8523_start_rtc(client);
		return err;
	}

	return pcf8523_start_rtc(client);
}

#ifdef CONFIG_RTC_INTF_DEV
static int pcf8523_rtc_ioctl(struct device *dev, unsigned int cmd,
			     unsigned long arg)
{
	struct i2c_client *client = to_i2c_client(dev);
	int ret;

	switch (cmd) {
	case RTC_VL_READ:
		ret = pcf8523_voltage_low(client);
		if (ret < 0)
			return ret;
		if (ret)
			ret = RTC_VL_BACKUP_LOW;

		return put_user(ret, (unsigned int __user *)arg);

	default:
		return -ENOIOCTLCMD;
	}
}
#else
#define pcf8523_rtc_ioctl NULL
#endif

static int pcf8523_rtc_read_offset(struct device *dev, long *offset)
{
	struct i2c_client *client = to_i2c_client(dev);
	int err;
	u8 value;
	s8 val;

	err = pcf8523_read(client, REG_OFFSET, &value);
	if (err < 0)
		return err;

	/* sign extend the 7-bit offset value */
	val = value << 1;
	*offset = (value & REG_OFFSET_MODE ? 4069 : 4340) * (val >> 1);

	return 0;
}

static int pcf8523_rtc_set_offset(struct device *dev, long offset)
{
	struct i2c_client *client = to_i2c_client(dev);
	long reg_m0, reg_m1;
	u8 value;

	reg_m0 = clamp(DIV_ROUND_CLOSEST(offset, 4340), -64L, 63L);
	reg_m1 = clamp(DIV_ROUND_CLOSEST(offset, 4069), -64L, 63L);

	if (abs(reg_m0 * 4340 - offset) < abs(reg_m1 * 4069 - offset))
		value = reg_m0 & 0x7f;
	else
		value = (reg_m1 & 0x7f) | REG_OFFSET_MODE;

	return pcf8523_write(client, REG_OFFSET, value);
}

static const struct rtc_class_ops pcf8523_rtc_ops = {
	.read_time = pcf8523_rtc_read_time,
	.set_time = pcf8523_rtc_set_time,
	.ioctl = pcf8523_rtc_ioctl,
	.read_offset = pcf8523_rtc_read_offset,
	.set_offset = pcf8523_rtc_set_offset,
};

static int pcf8523_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	struct rtc_device *rtc;
	int err;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
		return -ENODEV;

	err = pcf8523_load_capacitance(client);
	if (err < 0)
		dev_warn(&client->dev, "failed to set xtal load capacitance: %d",
			 err);

	err = pcf8523_set_pm(client, 0);
	if (err < 0)
		return err;

	rtc = devm_rtc_device_register(&client->dev, DRIVER_NAME,
				       &pcf8523_rtc_ops, THIS_MODULE);
	if (IS_ERR(rtc))
		return PTR_ERR(rtc);

	return 0;
}

static const struct i2c_device_id pcf8523_id[] = {
	{ "pcf8523", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, pcf8523_id);

#ifdef CONFIG_OF
static const struct of_device_id pcf8523_of_match[] = {
	{ .compatible = "nxp,pcf8523" },
	{ .compatible = "microcrystal,rv8523" },
	{ }
};
MODULE_DEVICE_TABLE(of, pcf8523_of_match);
#endif

static struct i2c_driver pcf8523_driver = {
	.driver = {
		.name = DRIVER_NAME,
		.of_match_table = of_match_ptr(pcf8523_of_match),
	},
	.probe = pcf8523_probe,
	.id_table = pcf8523_id,
};
module_i2c_driver(pcf8523_driver);

MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
MODULE_DESCRIPTION("NXP PCF8523 RTC driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
f803f0d0 TR	2	/*
f803f0d0 TR	3	* Copyright (C) 2012 Avionic Design GmbH
f803f0d0 TR	4	*/
	5
	6	#include <linux/bcd.h>
	7	#include <linux/i2c.h>
	8	#include <linux/module.h>
	9	#include <linux/rtc.h>
	10	#include <linux/of.h>
	11
	12	#define DRIVER_NAME "rtc-pcf8523"
	13
	14	#define REG_CONTROL1 0x00
	15	#define REG_CONTROL1_CAP_SEL (1 << 7)
	16	#define REG_CONTROL1_STOP (1 << 5)
	17
	18	#define REG_CONTROL3 0x02
	19	#define REG_CONTROL3_PM_BLD (1 << 7) /* battery low detection disabled */
	20	#define REG_CONTROL3_PM_VDD (1 << 6) /* switch-over disabled */
	21	#define REG_CONTROL3_PM_DSM (1 << 5) /* direct switching mode */
	22	#define REG_CONTROL3_PM_MASK 0xe0
f32bc70d	23	#define REG_CONTROL3_BLF (1 << 2) /* battery low bit, read-only */
f803f0d0 TR	24
	25	#define REG_SECONDS 0x03
	26	#define REG_SECONDS_OS (1 << 7)
	27
	28	#define REG_MINUTES 0x04
	29	#define REG_HOURS 0x05
	30	#define REG_DAYS 0x06
	31	#define REG_WEEKDAYS 0x07
	32	#define REG_MONTHS 0x08
	33	#define REG_YEARS 0x09
	34
bc3bee02 RK	35	#define REG_OFFSET 0x0e
	36	#define REG_OFFSET_MODE BIT(7)
	37
f803f0d0 TR	38	static int pcf8523_read(struct i2c_client client, u8 reg, u8 valuep)
	39	{
	40	struct i2c_msg msgs[2];
	41	u8 value = 0;
	42	int err;
	43
	44	msgs[0].addr = client->addr;
	45	msgs[0].flags = 0;
	46	msgs[0].len = sizeof(reg);
	47	msgs[0].buf = ®
	48
	49	msgs[1].addr = client->addr;
	50	msgs[1].flags = I2C_M_RD;
	51	msgs[1].len = sizeof(value);
	52	msgs[1].buf = &value;
	53
	54	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	55	if (err < 0)
	56	return err;
	57
	58	*valuep = value;
	59
	60	return 0;
	61	}
	62
	63	static int pcf8523_write(struct i2c_client *client, u8 reg, u8 value)
	64	{
	65	u8 buffer[2] = { reg, value };
	66	struct i2c_msg msg;
	67	int err;
	68
	69	msg.addr = client->addr;
	70	msg.flags = 0;
	71	msg.len = sizeof(buffer);
	72	msg.buf = buffer;
	73
	74	err = i2c_transfer(client->adapter, &msg, 1);
	75	if (err < 0)
	76	return err;
	77
	78	return 0;
	79	}
	80
ecb4a353 BS	81	static int pcf8523_voltage_low(struct i2c_client *client)
	82	{
	83	u8 value;
	84	int err;
	85
	86	err = pcf8523_read(client, REG_CONTROL3, &value);
	87	if (err < 0)
	88	return err;
	89
	90	return !!(value & REG_CONTROL3_BLF);
	91	}
	92
189927e7	93	static int pcf8523_load_capacitance(struct i2c_client *client)
f803f0d0	94	{
189927e7	95	u32 load;
f803f0d0 TR	96	u8 value;
	97	int err;
	98
	99	err = pcf8523_read(client, REG_CONTROL1, &value);
	100	if (err < 0)
	101	return err;
	102
189927e7 SR	103	load = 12500;
	104	of_property_read_u32(client->dev.of_node, "quartz-load-femtofarads",
	105	&load);
	106
	107	switch (load) {
	108	default:
	109	dev_warn(&client->dev, "Unknown quartz-load-femtofarads value: %d. Assuming 12500",
	110	load);
df561f66	111	fallthrough;
189927e7	112	case 12500:
f803f0d0	113	value \|= REG_CONTROL1_CAP_SEL;
189927e7 SR	114	break;
	115	case 7000:
	116	value &= ~REG_CONTROL1_CAP_SEL;
	117	break;
	118	}
f803f0d0 TR	119
f803f0d0 TR	120	err = pcf8523_write(client, REG_CONTROL1, value);
f803f0d0 TR	121
	122	return err;
	123	}
	124
	125	static int pcf8523_set_pm(struct i2c_client *client, u8 pm)
	126	{
	127	u8 value;
	128	int err;
	129
	130	err = pcf8523_read(client, REG_CONTROL3, &value);
	131	if (err < 0)
	132	return err;
	133
	134	value = (value & ~REG_CONTROL3_PM_MASK) \| pm;
	135
	136	err = pcf8523_write(client, REG_CONTROL3, value);
	137	if (err < 0)
	138	return err;
	139
	140	return 0;
	141	}
	142
	143	static int pcf8523_stop_rtc(struct i2c_client *client)
	144	{
	145	u8 value;
	146	int err;
	147
	148	err = pcf8523_read(client, REG_CONTROL1, &value);
	149	if (err < 0)
	150	return err;
	151
	152	value \|= REG_CONTROL1_STOP;
	153
	154	err = pcf8523_write(client, REG_CONTROL1, value);
	155	if (err < 0)
	156	return err;
	157
	158	return 0;
	159	}
	160
	161	static int pcf8523_start_rtc(struct i2c_client *client)
	162	{
	163	u8 value;
	164	int err;
	165
	166	err = pcf8523_read(client, REG_CONTROL1, &value);
	167	if (err < 0)
	168	return err;
	169
	170	value &= ~REG_CONTROL1_STOP;
	171
	172	err = pcf8523_write(client, REG_CONTROL1, value);
	173	if (err < 0)
	174	return err;
	175
	176	return 0;
	177	}
	178
	179	static int pcf8523_rtc_read_time(struct device dev, struct rtc_time tm)
	180	{
	181	struct i2c_client *client = to_i2c_client(dev);
	182	u8 start = REG_SECONDS, regs[7];
	183	struct i2c_msg msgs[2];
	184	int err;
185
ecb4a353 BS	186	err = pcf8523_voltage_low(client);
	187	if (err < 0) {
	188	return err;
	189	} else if (err > 0) {
	190	dev_err(dev, "low voltage detected, time is unreliable\n");
	191	return -EINVAL;
	192	}
	193
f803f0d0 TR	194	msgs[0].addr = client->addr;
	195	msgs[0].flags = 0;
	196	msgs[0].len = 1;
	197	msgs[0].buf = &start;
	198
	199	msgs[1].addr = client->addr;
	200	msgs[1].flags = I2C_M_RD;
	201	msgs[1].len = sizeof(regs);
	202	msgs[1].buf = regs;
	203
	204	err = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
	205	if (err < 0)
	206	return err;
	207
ede44c90 AB	208	if (regs[0] & REG_SECONDS_OS)
ede44c90 AB	209	return -EINVAL;
f803f0d0 TR	210
	211	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
	212	tm->tm_min = bcd2bin(regs[1] & 0x7f);
	213	tm->tm_hour = bcd2bin(regs[2] & 0x3f);
	214	tm->tm_mday = bcd2bin(regs[3] & 0x3f);
	215	tm->tm_wday = regs[4] & 0x7;
35738392	216	tm->tm_mon = bcd2bin(regs[5] & 0x1f) - 1;
f803f0d0 TR	217	tm->tm_year = bcd2bin(regs[6]) + 100;
f803f0d0 TR	218
22652ba7	219	return 0;
f803f0d0 TR	220	}
	221
	222	static int pcf8523_rtc_set_time(struct device dev, struct rtc_time tm)
	223	{
	224	struct i2c_client *client = to_i2c_client(dev);
	225	struct i2c_msg msg;
	226	u8 regs[8];
	227	int err;
	228
fbbf53f7 UKK	229	/*
	230	* The hardware can only store values between 0 and 99 in it's YEAR
	231	* register (with 99 overflowing to 0 on increment).
	232	* After 2100-02-28 we could start interpreting the year to be in the
	233	* interval [2100, 2199], but there is no path to switch in a smooth way
	234	* because the chip handles YEAR=0x00 (and the out-of-spec
	235	* YEAR=0xa0) as a leap year, but 2100 isn't.
	236	*/
	237	if (tm->tm_year < 100 \|\| tm->tm_year >= 200)
	238	return -EINVAL;
	239
f803f0d0 TR	240	err = pcf8523_stop_rtc(client);
	241	if (err < 0)
	242	return err;
	243
	244	regs[0] = REG_SECONDS;
ede44c90	245	/* This will purposely overwrite REG_SECONDS_OS */
f803f0d0 TR	246	regs[1] = bin2bcd(tm->tm_sec);
	247	regs[2] = bin2bcd(tm->tm_min);
	248	regs[3] = bin2bcd(tm->tm_hour);
	249	regs[4] = bin2bcd(tm->tm_mday);
	250	regs[5] = tm->tm_wday;
35738392	251	regs[6] = bin2bcd(tm->tm_mon + 1);
f803f0d0 TR	252	regs[7] = bin2bcd(tm->tm_year - 100);
	253
	254	msg.addr = client->addr;
	255	msg.flags = 0;
	256	msg.len = sizeof(regs);
	257	msg.buf = regs;
	258
	259	err = i2c_transfer(client->adapter, &msg, 1);
	260	if (err < 0) {
	261	/*
	262	* If the time cannot be set, restart the RTC anyway. Note
	263	* that errors are ignored if the RTC cannot be started so
	264	* that we have a chance to propagate the original error.
	265	*/
	266	pcf8523_start_rtc(client);
	267	return err;
	268	}
	269
	270	return pcf8523_start_rtc(client);
	271	}
	272
f32bc70d JN	273	#ifdef CONFIG_RTC_INTF_DEV
	274	static int pcf8523_rtc_ioctl(struct device *dev, unsigned int cmd,
	275	unsigned long arg)
	276	{
	277	struct i2c_client *client = to_i2c_client(dev);
ecb4a353	278	int ret;
f32bc70d JN	279
	280	switch (cmd) {
	281	case RTC_VL_READ:
ecb4a353 BS	282	ret = pcf8523_voltage_low(client);
	283	if (ret < 0)
	284	return ret;
244cf8f0 AB	285	if (ret)
244cf8f0 AB	286	ret = RTC_VL_BACKUP_LOW;
f32bc70d	287
244cf8f0	288	return put_user(ret, (unsigned int __user *)arg);
f32bc70d	289
f32bc70d JN	290	default:
	291	return -ENOIOCTLCMD;
	292	}
	293	}
	294	#else
	295	#define pcf8523_rtc_ioctl NULL
	296	#endif
	297
bc3bee02 RK	298	static int pcf8523_rtc_read_offset(struct device dev, long offset)
	299	{
	300	struct i2c_client *client = to_i2c_client(dev);
	301	int err;
	302	u8 value;
	303	s8 val;
	304
	305	err = pcf8523_read(client, REG_OFFSET, &value);
	306	if (err < 0)
	307	return err;
	308
	309	/* sign extend the 7-bit offset value */
	310	val = value << 1;
	311	offset = (value & REG_OFFSET_MODE ? 4069 : 4340) (val >> 1);
	312
	313	return 0;
	314	}
	315
	316	static int pcf8523_rtc_set_offset(struct device *dev, long offset)
	317	{
	318	struct i2c_client *client = to_i2c_client(dev);
	319	long reg_m0, reg_m1;
	320	u8 value;
	321
	322	reg_m0 = clamp(DIV_ROUND_CLOSEST(offset, 4340), -64L, 63L);
	323	reg_m1 = clamp(DIV_ROUND_CLOSEST(offset, 4069), -64L, 63L);
	324
	325	if (abs(reg_m0 * 4340 - offset) < abs(reg_m1 * 4069 - offset))
	326	value = reg_m0 & 0x7f;
	327	else
	328	value = (reg_m1 & 0x7f) \| REG_OFFSET_MODE;
	329
	330	return pcf8523_write(client, REG_OFFSET, value);
	331	}
	332
f803f0d0 TR	333	static const struct rtc_class_ops pcf8523_rtc_ops = {
	334	.read_time = pcf8523_rtc_read_time,
	335	.set_time = pcf8523_rtc_set_time,
f32bc70d	336	.ioctl = pcf8523_rtc_ioctl,
bc3bee02 RK	337	.read_offset = pcf8523_rtc_read_offset,
bc3bee02 RK	338	.set_offset = pcf8523_rtc_set_offset,
f803f0d0 TR	339	};
	340
	341	static int pcf8523_probe(struct i2c_client *client,
	342	const struct i2c_device_id *id)
	343	{
93966243	344	struct rtc_device *rtc;
f803f0d0 TR	345	int err;
	346
	347	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
	348	return -ENODEV;
	349
189927e7	350	err = pcf8523_load_capacitance(client);
f803f0d0	351	if (err < 0)
189927e7 SR	352	dev_warn(&client->dev, "failed to set xtal load capacitance: %d",
189927e7 SR	353	err);
f803f0d0 TR	354
	355	err = pcf8523_set_pm(client, 0);
	356	if (err < 0)
	357	return err;
	358
93966243	359	rtc = devm_rtc_device_register(&client->dev, DRIVER_NAME,
f803f0d0	360	&pcf8523_rtc_ops, THIS_MODULE);
93966243 NI	361	if (IS_ERR(rtc))
93966243 NI	362	return PTR_ERR(rtc);
f803f0d0 TR	363
	364	return 0;
	365	}
	366
f803f0d0 TR	367	static const struct i2c_device_id pcf8523_id[] = {
	368	{ "pcf8523", 0 },
	369	{ }
	370	};
	371	MODULE_DEVICE_TABLE(i2c, pcf8523_id);
	372
	373	#ifdef CONFIG_OF
	374	static const struct of_device_id pcf8523_of_match[] = {
	375	{ .compatible = "nxp,pcf8523" },
7c617e0c	376	{ .compatible = "microcrystal,rv8523" },
f803f0d0 TR	377	{ }
	378	};
	379	MODULE_DEVICE_TABLE(of, pcf8523_of_match);
	380	#endif
	381
	382	static struct i2c_driver pcf8523_driver = {
	383	.driver = {
	384	.name = DRIVER_NAME,
f803f0d0 TR	385	.of_match_table = of_match_ptr(pcf8523_of_match),
	386	},
	387	.probe = pcf8523_probe,
f803f0d0 TR	388	.id_table = pcf8523_id,
	389	};
	390	module_i2c_driver(pcf8523_driver);
	391
	392	MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
	393	MODULE_DESCRIPTION("NXP PCF8523 RTC driver");
	394	MODULE_LICENSE("GPL v2");