// SPDX-License-Identifier: GPL-2.0-only/* * An I2C driver for the Philips PCF8563 RTC * Copyright 2005-06 Tower Technologies * * Author: Alessandro Zummo <a.zummo@towertech.it> * Maintainers: http://www.nslu2-linux.org/ * * based on the other drivers in this same directory. * * https://www.nxp.com/docs/en/data-sheet/PCF8563.pdf */ #include <linux/bcd.h>#include <linux/clk-provider.h>#include <linux/err.h>#include <linux/i2c.h>#include <linux/module.h>#include <linux/of.h>#include <linux/regmap.h>#include <linux/rtc.h>#include <linux/slab.h> #define PCF8563_REG_ST1		0x00 /* status */#define PCF8563_REG_ST2		0x01#define PCF8563_BIT_AIE		BIT(1)#define PCF8563_BIT_AF		BIT(3)#define PCF8563_BITS_ST2_N	(7 << 5) #define PCF8563_REG_SC		0x02 /* datetime */#define PCF8563_REG_MN		0x03#define PCF8563_REG_HR		0x04#define PCF8563_REG_DM		0x05#define PCF8563_REG_DW		0x06#define PCF8563_REG_MO		0x07#define PCF8563_REG_YR		0x08 #define PCF8563_REG_AMN		0x09 /* alarm */ #define PCF8563_REG_CLKO		0x0D /* clock out */#define PCF8563_REG_CLKO_FE		0x80 /* clock out enabled */#define PCF8563_REG_CLKO_F_MASK		0x03 /* frequenc mask */#define PCF8563_REG_CLKO_F_32768HZ	0x00#define PCF8563_REG_CLKO_F_1024HZ	0x01#define PCF8563_REG_CLKO_F_32HZ		0x02#define PCF8563_REG_CLKO_F_1HZ		0x03 #define PCF8563_REG_TMRC	0x0E /* timer control */#define PCF8563_TMRC_ENABLE	BIT(7)#define PCF8563_TMRC_4096	0#define PCF8563_TMRC_64		1#define PCF8563_TMRC_1		2#define PCF8563_TMRC_1_60	3#define PCF8563_TMRC_MASK	3 #define PCF8563_REG_TMR		0x0F /* timer */ #define PCF8563_SC_LV		0x80 /* low voltage */#define PCF8563_MO_C		0x80 /* century */ static struct i2c_driver pcf8563_driver; struct pcf8563 {	struct rtc_device *rtc;	/*	 * The meaning of MO_C bit varies by the chip type.	 * From PCF8563 datasheet: this bit is toggled when the years	 * register overflows from 99 to 00	 *   0 indicates the century is 20xx	 *   1 indicates the century is 19xx	 * From RTC8564 datasheet: this bit indicates change of	 * century. When the year digit data overflows from 99 to 00,	 * this bit is set. By presetting it to 0 while still in the	 * 20th century, it will be set in year 2000, ...	 * There seems no reliable way to know how the system use this	 * bit.  So let's do it heuristically, assuming we are live in	 * 1970...2069.	 */	int c_polarity;	/* 0: MO_C=1 means 19xx, otherwise MO_C=1 means 20xx */ 	struct regmap *regmap;#ifdef CONFIG_COMMON_CLK	struct clk_hw		clkout_hw;#endif}; static int pcf8563_set_alarm_mode(struct pcf8563 *pcf8563, bool on){	u32 buf;	int err; 	err = regmap_read(pcf8563->regmap, PCF8563_REG_ST2, &buf);	if (err < 0)		return err; 	if (on)		buf |= PCF8563_BIT_AIE;	else		buf &= ~PCF8563_BIT_AIE; 	buf &= ~(PCF8563_BIT_AF | PCF8563_BITS_ST2_N); 	return regmap_write(pcf8563->regmap, PCF8563_REG_ST2, buf);} static int pcf8563_get_alarm_mode(struct pcf8563 *pcf8563, unsigned char *en,				  unsigned char *pen){	u32 buf;	int err; 	err = regmap_read(pcf8563->regmap, PCF8563_REG_ST2, &buf);	if (err < 0)		return err; 	if (en)		*en = !!(buf & PCF8563_BIT_AIE);	if (pen)		*pen = !!(buf & PCF8563_BIT_AF); 	return 0;} static irqreturn_t pcf8563_irq(int irq, void *dev_id){	struct pcf8563 *pcf8563 = dev_id;	char pending;	int err; 	err = pcf8563_get_alarm_mode(pcf8563, NULL, &pending);	if (err)		return IRQ_NONE; 	if (pending) {		rtc_update_irq(pcf8563->rtc, 1, RTC_IRQF | RTC_AF);		pcf8563_set_alarm_mode(pcf8563, 1);		return IRQ_HANDLED;	} 	return IRQ_NONE;} /* * In the routines that deal directly with the pcf8563 hardware, we use * rtc_time -- month 0-11, hour 0-23, yr = calendar year-epoch. */static int pcf8563_rtc_read_time(struct device *dev, struct rtc_time *tm){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev);	unsigned char buf[9];	int err; 	err = regmap_bulk_read(pcf8563->regmap, PCF8563_REG_ST1, buf,			       sizeof(buf));	if (err < 0)		return err; 	if (buf[PCF8563_REG_SC] & PCF8563_SC_LV) {		dev_err(dev,			"low voltage detected, date/time is not reliable.\n");		return -EINVAL;	} 	dev_dbg(dev,		"%s: raw data is st1=%02x, st2=%02x, sec=%02x, min=%02x, hr=%02x, "		"mday=%02x, wday=%02x, mon=%02x, year=%02x\n",		__func__,		buf[0], buf[1], buf[2], buf[3],		buf[4], buf[5], buf[6], buf[7],		buf[8]); 	tm->tm_sec = bcd2bin(buf[PCF8563_REG_SC] & 0x7F);	tm->tm_min = bcd2bin(buf[PCF8563_REG_MN] & 0x7F);	tm->tm_hour = bcd2bin(buf[PCF8563_REG_HR] & 0x3F); /* rtc hr 0-23 */	tm->tm_mday = bcd2bin(buf[PCF8563_REG_DM] & 0x3F);	tm->tm_wday = buf[PCF8563_REG_DW] & 0x07;	tm->tm_mon = bcd2bin(buf[PCF8563_REG_MO] & 0x1F) - 1; /* rtc mn 1-12 */	tm->tm_year = bcd2bin(buf[PCF8563_REG_YR]) + 100;	/* detect the polarity heuristically. see note above. */	pcf8563->c_polarity = (buf[PCF8563_REG_MO] & PCF8563_MO_C) ?		(tm->tm_year >= 100) : (tm->tm_year < 100); 	dev_dbg(dev, "%s: tm is secs=%d, mins=%d, hours=%d, "		"mday=%d, mon=%d, year=%d, wday=%d\n",		__func__,		tm->tm_sec, tm->tm_min, tm->tm_hour,		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 	return 0;} static int pcf8563_rtc_set_time(struct device *dev, struct rtc_time *tm){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev);	unsigned char buf[9]; 	dev_dbg(dev, "%s: secs=%d, mins=%d, hours=%d, "		"mday=%d, mon=%d, year=%d, wday=%d\n",		__func__,		tm->tm_sec, tm->tm_min, tm->tm_hour,		tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); 	/* hours, minutes and seconds */	buf[PCF8563_REG_SC] = bin2bcd(tm->tm_sec);	buf[PCF8563_REG_MN] = bin2bcd(tm->tm_min);	buf[PCF8563_REG_HR] = bin2bcd(tm->tm_hour); 	buf[PCF8563_REG_DM] = bin2bcd(tm->tm_mday); 	/* month, 1 - 12 */	buf[PCF8563_REG_MO] = bin2bcd(tm->tm_mon + 1); 	/* year and century */	buf[PCF8563_REG_YR] = bin2bcd(tm->tm_year - 100);	if (pcf8563->c_polarity ? (tm->tm_year >= 100) : (tm->tm_year < 100))		buf[PCF8563_REG_MO] |= PCF8563_MO_C; 	buf[PCF8563_REG_DW] = tm->tm_wday & 0x07; 	return regmap_bulk_write(pcf8563->regmap, PCF8563_REG_SC,				buf + PCF8563_REG_SC,				sizeof(buf) - PCF8563_REG_SC);} static int pcf8563_rtc_ioctl(struct device *dev, unsigned int cmd, unsigned long arg){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev);	int ret; 	switch (cmd) {	case RTC_VL_READ:		ret = regmap_test_bits(pcf8563->regmap, PCF8563_REG_SC,				       PCF8563_SC_LV);		if (ret < 0)			return ret; 		return put_user(ret ? RTC_VL_DATA_INVALID : 0,				(unsigned int __user *)arg);	default:		return -ENOIOCTLCMD;	}} static int pcf8563_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *tm){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev);	unsigned char buf[4];	int err; 	err = regmap_bulk_read(pcf8563->regmap, PCF8563_REG_AMN, buf,			       sizeof(buf));	if (err < 0)		return err; 	dev_dbg(dev,		"%s: raw data is min=%02x, hr=%02x, mday=%02x, wday=%02x\n",		__func__, buf[0], buf[1], buf[2], buf[3]); 	tm->time.tm_sec = 0;	tm->time.tm_min = bcd2bin(buf[0] & 0x7F);	tm->time.tm_hour = bcd2bin(buf[1] & 0x3F);	tm->time.tm_mday = bcd2bin(buf[2] & 0x3F);	tm->time.tm_wday = bcd2bin(buf[3] & 0x7); 	err = pcf8563_get_alarm_mode(pcf8563, &tm->enabled, &tm->pending);	if (err < 0)		return err; 	dev_dbg(dev, "%s: tm is mins=%d, hours=%d, mday=%d, wday=%d,"		" enabled=%d, pending=%d\n", __func__, tm->time.tm_min,		tm->time.tm_hour, tm->time.tm_mday, tm->time.tm_wday,		tm->enabled, tm->pending); 	return 0;} static int pcf8563_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *tm){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev);	unsigned char buf[4];	int err; 	buf[0] = bin2bcd(tm->time.tm_min);	buf[1] = bin2bcd(tm->time.tm_hour);	buf[2] = bin2bcd(tm->time.tm_mday);	buf[3] = tm->time.tm_wday & 0x07; 	err = regmap_bulk_write(pcf8563->regmap, PCF8563_REG_AMN, buf,				sizeof(buf));	if (err)		return err; 	return pcf8563_set_alarm_mode(pcf8563, !!tm->enabled);} static int pcf8563_irq_enable(struct device *dev, unsigned int enabled){	struct pcf8563 *pcf8563 = dev_get_drvdata(dev); 	dev_dbg(dev, "%s: en=%d\n", __func__, enabled);	return pcf8563_set_alarm_mode(pcf8563, !!enabled);} #ifdef CONFIG_COMMON_CLK/* * Handling of the clkout */ #define clkout_hw_to_pcf8563(_hw) container_of(_hw, struct pcf8563, clkout_hw) static const int clkout_rates[] = {	32768,	1024,	32,	1,}; static unsigned long pcf8563_clkout_recalc_rate(struct clk_hw *hw,						unsigned long parent_rate){	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);	u32 buf;	int ret; 	ret = regmap_read(pcf8563->regmap, PCF8563_REG_CLKO, &buf);	if (ret < 0)		return 0; 	buf &= PCF8563_REG_CLKO_F_MASK;	return clkout_rates[buf];} static int pcf8563_clkout_determine_rate(struct clk_hw *hw,					 struct clk_rate_request *req){	int i; 	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)		if (clkout_rates[i] <= req->rate) {			req->rate = clkout_rates[i]; 			return 0;		} 	req->rate = clkout_rates[0]; 	return 0;} static int pcf8563_clkout_set_rate(struct clk_hw *hw, unsigned long rate,				   unsigned long parent_rate){	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);	int i, ret;	u32 buf; 	ret = regmap_read(pcf8563->regmap, PCF8563_REG_CLKO, &buf);	if (ret < 0)		return ret; 	for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)		if (clkout_rates[i] == rate) {			buf &= ~PCF8563_REG_CLKO_F_MASK;			buf |= i;			return regmap_update_bits(pcf8563->regmap,					    PCF8563_REG_CLKO,					    PCF8563_REG_CLKO_F_MASK,					    buf);		} 	return -EINVAL;} static int pcf8563_clkout_control(struct clk_hw *hw, bool enable){	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);	u32 buf;	int ret; 	ret = regmap_read(pcf8563->regmap, PCF8563_REG_CLKO, &buf);	if (ret < 0)		return ret; 	if (enable)		buf |= PCF8563_REG_CLKO_FE;	else		buf &= ~PCF8563_REG_CLKO_FE; 	return regmap_update_bits(pcf8563->regmap, PCF8563_REG_CLKO,				  PCF8563_REG_CLKO_FE, buf);} static int pcf8563_clkout_prepare(struct clk_hw *hw){	return pcf8563_clkout_control(hw, 1);} static void pcf8563_clkout_unprepare(struct clk_hw *hw){	pcf8563_clkout_control(hw, 0);} static int pcf8563_clkout_is_prepared(struct clk_hw *hw){	struct pcf8563 *pcf8563 = clkout_hw_to_pcf8563(hw);	u32 buf;	int ret; 	ret = regmap_read(pcf8563->regmap, PCF8563_REG_CLKO, &buf);	if (ret < 0)		return ret; 	return !!(buf & PCF8563_REG_CLKO_FE);} static const struct clk_ops pcf8563_clkout_ops = {	.prepare = pcf8563_clkout_prepare,	.unprepare = pcf8563_clkout_unprepare,	.is_prepared = pcf8563_clkout_is_prepared,	.recalc_rate = pcf8563_clkout_recalc_rate,	.determine_rate = pcf8563_clkout_determine_rate,	.set_rate = pcf8563_clkout_set_rate,}; static struct clk *pcf8563_clkout_register_clk(struct pcf8563 *pcf8563){	struct device_node *node = pcf8563->rtc->dev.parent->of_node;	struct clk_init_data init = {};	struct clk *clk;	int ret; 	/* disable the clkout output */	ret = regmap_clear_bits(pcf8563->regmap, PCF8563_REG_CLKO,				PCF8563_REG_CLKO_FE);	if (ret < 0)		return ERR_PTR(ret); 	init.name = "pcf8563-clkout";	init.ops = &pcf8563_clkout_ops;	init.flags = 0;	init.parent_names = NULL;	init.num_parents = 0;	pcf8563->clkout_hw.init = &init; 	/* optional override of the clockname */	of_property_read_string(node, "clock-output-names", &init.name); 	/* register the clock */	clk = devm_clk_register(&pcf8563->rtc->dev, &pcf8563->clkout_hw); 	if (!IS_ERR(clk))		devm_of_clk_add_hw_provider(pcf8563->rtc->dev.parent,					    of_clk_hw_simple_get,					    &pcf8563->clkout_hw); 	return clk;}#endif static const struct rtc_class_ops pcf8563_rtc_ops = {	.ioctl		= pcf8563_rtc_ioctl,	.read_time	= pcf8563_rtc_read_time,	.set_time	= pcf8563_rtc_set_time,	.read_alarm	= pcf8563_rtc_read_alarm,	.set_alarm	= pcf8563_rtc_set_alarm,	.alarm_irq_enable = pcf8563_irq_enable,}; static const struct regmap_config regmap_config = {	.reg_bits = 8,	.val_bits = 8,	.max_register = 0xF,}; static int pcf8563_probe(struct i2c_client *client){	struct pcf8563 *pcf8563;	int err; 	dev_dbg(&client->dev, "%s\n", __func__); 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))		return -ENODEV; 	pcf8563 = devm_kzalloc(&client->dev, sizeof(struct pcf8563),				GFP_KERNEL);	if (!pcf8563)		return -ENOMEM; 	pcf8563->regmap = devm_regmap_init_i2c(client, &regmap_config);	if (IS_ERR(pcf8563->regmap))		return PTR_ERR(pcf8563->regmap); 	i2c_set_clientdata(client, pcf8563);	device_set_wakeup_capable(&client->dev, 1); 	/* Set timer to lowest frequency to save power (ref Haoyu datasheet) */	err = regmap_set_bits(pcf8563->regmap, PCF8563_REG_TMRC,			      PCF8563_TMRC_1_60);	if (err < 0) {

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