[J-u-boot.git] / drivers / rtc / rv3029.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2018 Theobroma Systems Design und Consulting GmbH
 *
 * Based on a the Linux rtc-rv3029c2.c driver written by:
 *   Gregory Hermant <[email protected]>
 *   Michael Buesch <[email protected]>
 */

#include <command.h>
#include <dm.h>
#include <i2c.h>
#include <log.h>
#include <rtc.h>
#include <dm/device_compat.h>
#include <linux/bitops.h>
#include <linux/delay.h>

#define RTC_RV3029_PAGE_LEN             7

/* control section */
#define RV3029_ONOFF_CTRL		0x00
#define RV3029_ONOFF_CTRL_WE		BIT(0)
#define RV3029_ONOFF_CTRL_TE		BIT(1)
#define RV3029_ONOFF_CTRL_TAR		BIT(2)
#define RV3029_ONOFF_CTRL_EERE		BIT(3)
#define RV3029_ONOFF_CTRL_SRON		BIT(4)
#define RV3029_ONOFF_CTRL_TD0		BIT(5)
#define RV3029_ONOFF_CTRL_TD1		BIT(6)
#define RV3029_ONOFF_CTRL_CLKINT	BIT(7)
#define RV3029_IRQ_CTRL			0x01
#define RV3029_IRQ_CTRL_AIE		BIT(0)
#define RV3029_IRQ_CTRL_TIE		BIT(1)
#define RV3029_IRQ_CTRL_V1IE		BIT(2)
#define RV3029_IRQ_CTRL_V2IE		BIT(3)
#define RV3029_IRQ_CTRL_SRIE		BIT(4)
#define RV3029_IRQ_FLAGS		0x02
#define RV3029_IRQ_FLAGS_AF		BIT(0)
#define RV3029_IRQ_FLAGS_TF		BIT(1)
#define RV3029_IRQ_FLAGS_V1IF		BIT(2)
#define RV3029_IRQ_FLAGS_V2IF		BIT(3)
#define RV3029_IRQ_FLAGS_SRF		BIT(4)
#define RV3029_STATUS			0x03
#define RV3029_STATUS_VLOW1		BIT(2)
#define RV3029_STATUS_VLOW2		BIT(3)
#define RV3029_STATUS_SR		BIT(4)
#define RV3029_STATUS_PON		BIT(5)
#define RV3029_STATUS_EEBUSY		BIT(7)
#define RV3029_RST_CTRL			0x04
#define RV3029_RST_CTRL_SYSR		BIT(4)
#define RV3029_CONTROL_SECTION_LEN	0x05

/* watch section */
#define RV3029_W_SEC			0x08
#define RV3029_W_MINUTES		0x09
#define RV3029_W_HOURS			0x0A
#define RV3029_REG_HR_12_24		BIT(6) /* 24h/12h mode */
#define RV3029_REG_HR_PM		BIT(5) /* PM/AM bit in 12h mode */
#define RV3029_W_DATE			0x0B
#define RV3029_W_DAYS			0x0C
#define RV3029_W_MONTHS			0x0D
#define RV3029_W_YEARS			0x0E

/* eeprom control section */
#define RV3029_CONTROL_E2P_EECTRL	0x30
#define RV3029_TRICKLE_1K		BIT(4) /* 1.5K resistance */
#define RV3029_TRICKLE_5K		BIT(5) /* 5K   resistance */
#define RV3029_TRICKLE_20K		BIT(6) /* 20K  resistance */
#define RV3029_TRICKLE_80K		BIT(7) /* 80K  resistance */
#define RV3029_TRICKLE_MASK		(RV3029_TRICKLE_1K |\
					 RV3029_TRICKLE_5K |\
					 RV3029_TRICKLE_20K |\
					 RV3029_TRICKLE_80K)
#define RV3029_TRICKLE_SHIFT		4

static int rv3029_rtc_get(struct udevice *dev, struct rtc_time *tm)
{
	u8 regs[RTC_RV3029_PAGE_LEN];
	int ret;

	ret = dm_i2c_read(dev, RV3029_W_SEC, regs, sizeof(regs));
	if (ret < 0) {
		printf("%s: error reading RTC: %x\n", __func__, ret);
		return -EIO;
	}

	tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
	tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);

	/* HR field has a more complex interpretation */
	{
		const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];

		if (_hr & RV3029_REG_HR_12_24) {
			/* 12h format */
			tm->tm_hour = bcd2bin(_hr & 0x1f);
			if (_hr & RV3029_REG_HR_PM)	/* PM flag set */
				tm->tm_hour += 12;
		} else {
			/* 24h format */
			tm->tm_hour = bcd2bin(_hr & 0x3f);
		}
	}

	tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
	tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
	/* RTC supports only years > 1999 */
	tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 2000;
	tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;

	tm->tm_yday = 0;
	tm->tm_isdst = 0;

	debug("%s: %4d-%02d-%02d (wday=%d) %2d:%02d:%02d\n",
	      __func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	      tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);

	return 0;
}

static int rv3029_rtc_set(struct udevice *dev, const struct rtc_time *tm)
{
	u8 regs[RTC_RV3029_PAGE_LEN];

	debug("%s: %4d-%02d-%02d (wday=%d( %2d:%02d:%02d\n",
	      __func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	      tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);

	if (tm->tm_year < 2000) {
		printf("%s: year %d (before 2000) not supported\n",
		       __func__, tm->tm_year);
		return -EINVAL;
	}

	regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
	regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
	regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
	regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
	regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
	regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
	regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 2000);

	return dm_i2c_write(dev, RV3029_W_SEC, regs, sizeof(regs));
}

static int rv3029_rtc_reset(struct udevice *dev)
{
	u8 ctrl = RV3029_RST_CTRL_SYSR;
	unsigned long start;
	const unsigned long timeout_ms = 10000;
	int ret;

	/* trigger the system-reset */
	ret = dm_i2c_write(dev, RV3029_RST_CTRL, &ctrl, 1);
	if (ret < 0)
		return -EIO;

	/* wait for the system-reset to complete */
	start = get_timer(0);
	do {
		if (get_timer(start) > timeout_ms)
			return -ETIMEDOUT;

		ret = dm_i2c_read(dev, RV3029_RST_CTRL, &ctrl, 1);
		if (ret < 0)
			return -EIO;
	} while (ctrl & RV3029_RST_CTRL_SYSR);

	return 0;
}

static int rv3029_rtc_read8(struct udevice *dev, unsigned int reg)
{
	u8 data;
	int ret;

	ret = dm_i2c_read(dev, reg, &data, sizeof(data));
	return ret < 0 ? ret : data;
}

static int rv3029_rtc_write8(struct udevice *dev, unsigned int reg, int val)
{
	u8 data = val;

	return dm_i2c_write(dev, reg, &data, 1);
}

#if defined(OF_CONTROL)
static int rv3029_get_sr(struct udevice *dev, u8 *buf)
{
	int ret = dm_i2c_read(dev, RV3029_STATUS, buf, 1);

	if (ret < 0)
		return -EIO;

	dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
	return 0;
}

static int rv3029_set_sr(struct udevice *dev, u8 val)
{
	int ret;

	ret = dm_i2c_read(dev, RV3029_STATUS, &val, 1);
	if (ret < 0)
		return -EIO;

	dev_dbg(dev, "status = 0x%.2x (%d)\n", val, val);
	return 0;
}

static int rv3029_eeprom_busywait(struct udevice *dev)
{
	int i, ret;
	u8 sr;

	for (i = 100; i > 0; i--) {
		ret = rv3029_get_sr(dev, &sr);
		if (ret < 0)
			break;
		if (!(sr & RV3029_STATUS_EEBUSY))
			break;
		udelay(10000);
	}
	if (i <= 0) {
		dev_err(dev, "EEPROM busy wait timeout.\n");
		return -ETIMEDOUT;
	}

	return ret;
}

static int rv3029_update_bits(struct udevice *dev, u8 reg, u8 mask, u8 set)
{
	u8 buf;
	int ret;

	ret = dm_i2c_read(dev, reg, &buf, 1);
	if (ret < 0)
		return ret;

	if ((buf & mask) == (set && mask))
		return 0;

	buf = (buf & ~mask) | (set & mask);
	ret = dm_i2c_read(dev, reg, &buf, 1);
	if (ret < 0)
		return ret;

	return 0;
}

static int rv3029_eeprom_exit(struct udevice *dev)
{
	/* Re-enable eeprom refresh */
	return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
				  RV3029_ONOFF_CTRL_EERE,
				  RV3029_ONOFF_CTRL_EERE);
}

static int rv3029_eeprom_enter(struct udevice *dev)
{
	int ret;
	u8 sr;

	/* Check whether we are in the allowed voltage range. */
	ret = rv3029_get_sr(dev, &sr);
	if (ret < 0)
		return ret;
	if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
		/* We clear the bits and retry once just in case
		 * we had a brown out in early startup.
		 */
		sr &= ~RV3029_STATUS_VLOW1;
		sr &= ~RV3029_STATUS_VLOW2;
		ret = rv3029_set_sr(dev, sr);
		if (ret < 0)
			return ret;
		udelay(10000);
		ret = rv3029_get_sr(dev, &sr);
		if (ret < 0)
			return ret;
		if (sr & (RV3029_STATUS_VLOW1 | RV3029_STATUS_VLOW2)) {
			dev_err(dev, "Supply voltage is too low to safely access the EEPROM.\n");
			return -ENODEV;
		}
	}

	/* Disable eeprom refresh. */
	ret = rv3029_update_bits(dev,
				 RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE, 0);
	if (ret < 0)
		return ret;

	/* Wait for any previous eeprom accesses to finish. */
	ret = rv3029_eeprom_busywait(dev);
	if (ret < 0)
		rv3029_eeprom_exit(dev);

	return ret;
}

static int rv3029_eeprom_read(struct udevice *dev, u8 reg,
			      u8 buf[], size_t len)
{
	int ret, err;

	err = rv3029_eeprom_enter(dev);
	if (err < 0)
		return err;

	ret = dm_i2c_read(dev, reg, buf, len);

	err = rv3029_eeprom_exit(dev);
	if (err < 0)
		return err;

	return ret;
}

static int rv3029_eeprom_write(struct udevice *dev, u8 reg,
			       u8 const buf[], size_t len)
{
	int ret;
	size_t i;
	u8 tmp;

	ret = rv3029_eeprom_enter(dev);
	if (ret < 0)
		return ret;

	for (i = 0; i < len; i++, reg++) {
		ret = dm_i2c_read(dev, reg, &tmp, 1);
		if (ret < 0)
			break;
		if (tmp != buf[i]) {
			ret = dm_i2c_write(dev, reg, &buf[i], 1);
			if (ret < 0)
				break;
		}
		ret = rv3029_eeprom_busywait(dev);
		if (ret < 0)
			break;
	}

	ret = rv3029_eeprom_exit(dev);
	if (ret < 0)
		return ret;

	return 0;
}

static int rv3029_eeprom_update_bits(struct udevice *dev,
				     u8 reg, u8 mask, u8 set)
{
	u8 buf;
	int ret;

	ret = rv3029_eeprom_read(dev, reg, &buf, 1);
	if (ret < 0)
		return ret;

	/*
	 * If the EEPROM already reads the correct bitpattern, we don't need
	 * to update it.
	 */
	if ((buf & mask) == (set & mask))
		return 0;

	buf = (buf & ~mask) | (set & mask);
	ret = rv3029_eeprom_write(dev, reg, &buf, 1);
	if (ret < 0)
		return ret;

	return 0;
}

static void rv3029_trickle_config(struct udevice *dev)
{
	static const struct rv3029_trickle_tab_elem {
		u32 r;		/* resistance in ohms */
		u8 conf;	/* trickle config bits */
	} rv3029_trickle_tab[] = {
		{
			.r	= 1076,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
				  RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
		}, {
			.r	= 1091,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
				  RV3029_TRICKLE_20K,
		}, {
			.r	= 1137,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K |
				  RV3029_TRICKLE_80K,
		}, {
			.r	= 1154,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_5K,
		}, {
			.r	= 1371,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K |
				  RV3029_TRICKLE_80K,
		}, {
			.r	= 1395,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_20K,
		}, {
			.r	= 1472,
			.conf	= RV3029_TRICKLE_1K | RV3029_TRICKLE_80K,
		}, {
			.r	= 1500,
			.conf	= RV3029_TRICKLE_1K,
		}, {
			.r	= 3810,
			.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K |
				  RV3029_TRICKLE_80K,
		}, {
			.r	= 4000,
			.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_20K,
		}, {
			.r	= 4706,
			.conf	= RV3029_TRICKLE_5K | RV3029_TRICKLE_80K,
		}, {
			.r	= 5000,
			.conf	= RV3029_TRICKLE_5K,
		}, {
			.r	= 16000,
			.conf	= RV3029_TRICKLE_20K | RV3029_TRICKLE_80K,
		}, {
			.r	= 20000,
			.conf	= RV3029_TRICKLE_20K,
		}, {
			.r	= 80000,
			.conf	= RV3029_TRICKLE_80K,
		},
	};
	int err;
	u32 ohms;
	u8 trickle_set_bits = 0;

	/* Configure the trickle charger. */
	err = dev_read_u32(dev, "trickle-resistor-ohms", &ohms);

	if (!err) {
		/* Find trickle-charger config */
		for (int i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++)
			if (rv3029_trickle_tab[i].r >= ohms) {
				dev_dbg(dev, "trickle charger at %d ohms\n",
					rv3029_trickle_tab[i].r);
				trickle_set_bits = rv3029_trickle_tab[i].conf;
				break;
			}
	}

	dev_dbg(dev, "trickle charger config 0x%x\n", trickle_set_bits);
	err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
					RV3029_TRICKLE_MASK,
					trickle_set_bits);
	if (err < 0)
		dev_dbg(dev, "failed to update trickle charger\n");
}
#else
static inline void rv3029_trickle_config(struct udevice *dev)
{
}
#endif

static int rv3029_probe(struct udevice *dev)
{
	i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS |
				DM_I2C_CHIP_WR_ADDRESS);

	rv3029_trickle_config(dev);
	return 0;
}

static const struct rtc_ops rv3029_rtc_ops = {
	.get = rv3029_rtc_get,
	.set = rv3029_rtc_set,
	.read8 = rv3029_rtc_read8,
	.write8 = rv3029_rtc_write8,
	.reset = rv3029_rtc_reset,
};

static const struct udevice_id rv3029_rtc_ids[] = {
	{ .compatible = "mc,rv3029" },
	{ .compatible = "mc,rv3029c2" },
	{ }
};

U_BOOT_DRIVER(rtc_rv3029) = {
	.name	= "rtc-rv3029",
	.id	= UCLASS_RTC,
	.probe	= rv3029_probe,
	.of_match = rv3029_rtc_ids,
	.ops	= &rv3029_rtc_ops,
};
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
5c4fa2ee	2	/*
a73610d2 PT	3	* (C) Copyright 2018 Theobroma Systems Design und Consulting GmbH
	4	*
	5	* Based on a the Linux rtc-rv3029c2.c driver written by:
	6	* Gregory Hermant <[email protected]>
	7	* Michael Buesch <[email protected]>
5c4fa2ee	8	*/
a73610d2	9
5c4fa2ee	10	#include <command.h>
a73610d2	11	#include <dm.h>
5c4fa2ee	12	#include <i2c.h>
f7ae49fc	13	#include <log.h>
5c4fa2ee	14	#include <rtc.h>
336d4615	15	#include <dm/device_compat.h>
cd93d625	16	#include <linux/bitops.h>
c05ed00a	17	#include <linux/delay.h>
5c4fa2ee	18
a73610d2	19	#define RTC_RV3029_PAGE_LEN 7
71d19f30	20
a73610d2 PT	21	/* control section */
	22	#define RV3029_ONOFF_CTRL 0x00
	23	#define RV3029_ONOFF_CTRL_WE BIT(0)
	24	#define RV3029_ONOFF_CTRL_TE BIT(1)
	25	#define RV3029_ONOFF_CTRL_TAR BIT(2)
	26	#define RV3029_ONOFF_CTRL_EERE BIT(3)
	27	#define RV3029_ONOFF_CTRL_SRON BIT(4)
	28	#define RV3029_ONOFF_CTRL_TD0 BIT(5)
	29	#define RV3029_ONOFF_CTRL_TD1 BIT(6)
	30	#define RV3029_ONOFF_CTRL_CLKINT BIT(7)
	31	#define RV3029_IRQ_CTRL 0x01
	32	#define RV3029_IRQ_CTRL_AIE BIT(0)
	33	#define RV3029_IRQ_CTRL_TIE BIT(1)
	34	#define RV3029_IRQ_CTRL_V1IE BIT(2)
	35	#define RV3029_IRQ_CTRL_V2IE BIT(3)
	36	#define RV3029_IRQ_CTRL_SRIE BIT(4)
	37	#define RV3029_IRQ_FLAGS 0x02
	38	#define RV3029_IRQ_FLAGS_AF BIT(0)
	39	#define RV3029_IRQ_FLAGS_TF BIT(1)
	40	#define RV3029_IRQ_FLAGS_V1IF BIT(2)
	41	#define RV3029_IRQ_FLAGS_V2IF BIT(3)
	42	#define RV3029_IRQ_FLAGS_SRF BIT(4)
	43	#define RV3029_STATUS 0x03
	44	#define RV3029_STATUS_VLOW1 BIT(2)
	45	#define RV3029_STATUS_VLOW2 BIT(3)
	46	#define RV3029_STATUS_SR BIT(4)
	47	#define RV3029_STATUS_PON BIT(5)
	48	#define RV3029_STATUS_EEBUSY BIT(7)
	49	#define RV3029_RST_CTRL 0x04
	50	#define RV3029_RST_CTRL_SYSR BIT(4)
	51	#define RV3029_CONTROL_SECTION_LEN 0x05
5c4fa2ee	52
a73610d2 PT	53	/* watch section */
	54	#define RV3029_W_SEC 0x08
	55	#define RV3029_W_MINUTES 0x09
	56	#define RV3029_W_HOURS 0x0A
	57	#define RV3029_REG_HR_12_24 BIT(6) /* 24h/12h mode */
	58	#define RV3029_REG_HR_PM BIT(5) /* PM/AM bit in 12h mode */
	59	#define RV3029_W_DATE 0x0B
	60	#define RV3029_W_DAYS 0x0C
	61	#define RV3029_W_MONTHS 0x0D
	62	#define RV3029_W_YEARS 0x0E
5c4fa2ee	63
a73610d2 PT	64	/* eeprom control section */
	65	#define RV3029_CONTROL_E2P_EECTRL 0x30
	66	#define RV3029_TRICKLE_1K BIT(4) /* 1.5K resistance */
	67	#define RV3029_TRICKLE_5K BIT(5) /* 5K resistance */
	68	#define RV3029_TRICKLE_20K BIT(6) /* 20K resistance */
	69	#define RV3029_TRICKLE_80K BIT(7) /* 80K resistance */
	70	#define RV3029_TRICKLE_MASK (RV3029_TRICKLE_1K \|\
	71	RV3029_TRICKLE_5K \|\
	72	RV3029_TRICKLE_20K \|\
	73	RV3029_TRICKLE_80K)
	74	#define RV3029_TRICKLE_SHIFT 4
5c4fa2ee	75
a73610d2	76	static int rv3029_rtc_get(struct udevice dev, struct rtc_time tm)
5c4fa2ee	77	{
a73610d2 PT	78	u8 regs[RTC_RV3029_PAGE_LEN];
a73610d2 PT	79	int ret;
5c4fa2ee	80
a73610d2 PT	81	ret = dm_i2c_read(dev, RV3029_W_SEC, regs, sizeof(regs));
a73610d2 PT	82	if (ret < 0) {
5c4fa2ee	83	printf("%s: error reading RTC: %x\n", __func__, ret);
a73610d2 PT	84	return -EIO;
	85	}
	86
	87	tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
	88	tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
	89
	90	/* HR field has a more complex interpretation */
	91	{
	92	const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
	93
	94	if (_hr & RV3029_REG_HR_12_24) {
	95	/* 12h format */
	96	tm->tm_hour = bcd2bin(_hr & 0x1f);
	97	if (_hr & RV3029_REG_HR_PM) /* PM flag set */
	98	tm->tm_hour += 12;
	99	} else {
	100	/* 24h format */
	101	tm->tm_hour = bcd2bin(_hr & 0x3f);
	102	}
5c4fa2ee	103	}
a73610d2 PT	104
	105	tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
	106	tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
5c4fa2ee	107	/* RTC supports only years > 1999 */
a73610d2 PT	108	tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 2000;
	109	tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
	110
	111	tm->tm_yday = 0;
	112	tm->tm_isdst = 0;
5c4fa2ee	113
a73610d2 PT	114	debug("%s: %4d-%02d-%02d (wday=%d) %2d:%02d:%02d\n",
	115	__func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	116	tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
5c4fa2ee	117
5c4fa2ee HS	118	return 0;
	119	}
	120
a73610d2	121	static int rv3029_rtc_set(struct udevice dev, const struct rtc_time tm)
5c4fa2ee	122	{
a73610d2 PT	123	u8 regs[RTC_RV3029_PAGE_LEN];
	124
	125	debug("%s: %4d-%02d-%02d (wday=%d( %2d:%02d:%02d\n",
	126	__func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	127	tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
b633741b	128
a73610d2 PT	129	if (tm->tm_year < 2000) {
	130	printf("%s: year %d (before 2000) not supported\n",
	131	__func__, tm->tm_year);
	132	return -EINVAL;
5c4fa2ee	133	}
a73610d2 PT	134
	135	regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
	136	regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
	137	regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
	138	regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
	139	regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
	140	regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
	141	regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 2000);
	142
	143	return dm_i2c_write(dev, RV3029_W_SEC, regs, sizeof(regs));
5c4fa2ee HS	144	}
5c4fa2ee HS	145
a73610d2	146	static int rv3029_rtc_reset(struct udevice *dev)
71d19f30	147	{
a73610d2 PT	148	u8 ctrl = RV3029_RST_CTRL_SYSR;
	149	unsigned long start;
	150	const unsigned long timeout_ms = 10000;
	151	int ret;
71d19f30	152
a73610d2 PT	153	/* trigger the system-reset */
	154	ret = dm_i2c_write(dev, RV3029_RST_CTRL, &ctrl, 1);
	155	if (ret < 0)
	156	return -EIO;
71d19f30	157
a73610d2 PT	158	/* wait for the system-reset to complete */
	159	start = get_timer(0);
	160	do {
	161	if (get_timer(start) > timeout_ms)
	162	return -ETIMEDOUT;
71d19f30	163
a73610d2 PT	164	ret = dm_i2c_read(dev, RV3029_RST_CTRL, &ctrl, 1);
	165	if (ret < 0)
	166	return -EIO;
	167	} while (ctrl & RV3029_RST_CTRL_SYSR);
	168
	169	return 0;
71d19f30 HS	170	}
71d19f30 HS	171
a73610d2	172	static int rv3029_rtc_read8(struct udevice *dev, unsigned int reg)
71d19f30	173	{
a73610d2 PT	174	u8 data;
	175	int ret;
	176
	177	ret = dm_i2c_read(dev, reg, &data, sizeof(data));
	178	return ret < 0 ? ret : data;
	179	}
71d19f30	180
a73610d2 PT	181	static int rv3029_rtc_write8(struct udevice *dev, unsigned int reg, int val)
	182	{
	183	u8 data = val;
	184
	185	return dm_i2c_write(dev, reg, &data, 1);
	186	}
	187
	188	#if defined(OF_CONTROL)
	189	static int rv3029_get_sr(struct udevice dev, u8 buf)
	190	{
	191	int ret = dm_i2c_read(dev, RV3029_STATUS, buf, 1);
	192
	193	if (ret < 0)
	194	return -EIO;
	195
	196	dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
	197	return 0;
	198	}
71d19f30	199
a73610d2 PT	200	static int rv3029_set_sr(struct udevice *dev, u8 val)
	201	{
	202	int ret;
	203
	204	ret = dm_i2c_read(dev, RV3029_STATUS, &val, 1);
	205	if (ret < 0)
	206	return -EIO;
	207
	208	dev_dbg(dev, "status = 0x%.2x (%d)\n", val, val);
	209	return 0;
	210	}
	211
	212	static int rv3029_eeprom_busywait(struct udevice *dev)
	213	{
	214	int i, ret;
	215	u8 sr;
	216
	217	for (i = 100; i > 0; i--) {
	218	ret = rv3029_get_sr(dev, &sr);
	219	if (ret < 0)
	220	break;
	221	if (!(sr & RV3029_STATUS_EEBUSY))
71d19f30 HS	222	break;
	223	udelay(10000);
	224	}
a73610d2 PT	225	if (i <= 0) {
	226	dev_err(dev, "EEPROM busy wait timeout.\n");
	227	return -ETIMEDOUT;
	228	}
	229
	230	return ret;
71d19f30 HS	231	}
71d19f30 HS	232
a73610d2	233	static int rv3029_update_bits(struct udevice *dev, u8 reg, u8 mask, u8 set)
5c4fa2ee	234	{
a73610d2 PT	235	u8 buf;
a73610d2 PT	236	int ret;
5c4fa2ee	237
a73610d2 PT	238	ret = dm_i2c_read(dev, reg, &buf, 1);
	239	if (ret < 0)
	240	return ret;
71d19f30	241
a73610d2 PT	242	if ((buf & mask) == (set && mask))
a73610d2 PT	243	return 0;
71d19f30	244
a73610d2 PT	245	buf = (buf & ~mask) \| (set & mask);
	246	ret = dm_i2c_read(dev, reg, &buf, 1);
	247	if (ret < 0)
	248	return ret;
	249
	250	return 0;
	251	}
	252
	253	static int rv3029_eeprom_exit(struct udevice *dev)
	254	{
	255	/* Re-enable eeprom refresh */
	256	return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
	257	RV3029_ONOFF_CTRL_EERE,
	258	RV3029_ONOFF_CTRL_EERE);
	259	}
	260
	261	static int rv3029_eeprom_enter(struct udevice *dev)
	262	{
	263	int ret;
	264	u8 sr;
	265
	266	/* Check whether we are in the allowed voltage range. */
	267	ret = rv3029_get_sr(dev, &sr);
	268	if (ret < 0)
	269	return ret;
	270	if (sr & (RV3029_STATUS_VLOW1 \| RV3029_STATUS_VLOW2)) {
	271	/* We clear the bits and retry once just in case
	272	* we had a brown out in early startup.
71d19f30	273	*/
a73610d2 PT	274	sr &= ~RV3029_STATUS_VLOW1;
	275	sr &= ~RV3029_STATUS_VLOW2;
	276	ret = rv3029_set_sr(dev, sr);
	277	if (ret < 0)
	278	return ret;
71d19f30	279	udelay(10000);
a73610d2 PT	280	ret = rv3029_get_sr(dev, &sr);
	281	if (ret < 0)
	282	return ret;
	283	if (sr & (RV3029_STATUS_VLOW1 \| RV3029_STATUS_VLOW2)) {
	284	dev_err(dev, "Supply voltage is too low to safely access the EEPROM.\n");
	285	return -ENODEV;
	286	}
	287	}
	288
	289	/* Disable eeprom refresh. */
	290	ret = rv3029_update_bits(dev,
	291	RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE, 0);
	292	if (ret < 0)
	293	return ret;
	294
	295	/* Wait for any previous eeprom accesses to finish. */
	296	ret = rv3029_eeprom_busywait(dev);
	297	if (ret < 0)
	298	rv3029_eeprom_exit(dev);
	299
	300	return ret;
	301	}
	302
	303	static int rv3029_eeprom_read(struct udevice *dev, u8 reg,
	304	u8 buf[], size_t len)
	305	{
	306	int ret, err;
	307
	308	err = rv3029_eeprom_enter(dev);
	309	if (err < 0)
	310	return err;
	311
	312	ret = dm_i2c_read(dev, reg, buf, len);
	313
	314	err = rv3029_eeprom_exit(dev);
	315	if (err < 0)
	316	return err;
	317
	318	return ret;
	319	}
	320
	321	static int rv3029_eeprom_write(struct udevice *dev, u8 reg,
	322	u8 const buf[], size_t len)
	323	{
	324	int ret;
	325	size_t i;
	326	u8 tmp;
	327
	328	ret = rv3029_eeprom_enter(dev);
	329	if (ret < 0)
	330	return ret;
	331
	332	for (i = 0; i < len; i++, reg++) {
	333	ret = dm_i2c_read(dev, reg, &tmp, 1);
	334	if (ret < 0)
	335	break;
	336	if (tmp != buf[i]) {
	337	ret = dm_i2c_write(dev, reg, &buf[i], 1);
	338	if (ret < 0)
	339	break;
	340	}
	341	ret = rv3029_eeprom_busywait(dev);
	342	if (ret < 0)
	343	break;
71d19f30	344	}
a73610d2 PT	345
	346	ret = rv3029_eeprom_exit(dev);
	347	if (ret < 0)
	348	return ret;
	349
	350	return 0;
	351	}
	352
	353	static int rv3029_eeprom_update_bits(struct udevice *dev,
	354	u8 reg, u8 mask, u8 set)
	355	{
	356	u8 buf;
	357	int ret;
	358
	359	ret = rv3029_eeprom_read(dev, reg, &buf, 1);
	360	if (ret < 0)
	361	return ret;
	362
	363	/*
	364	* If the EEPROM already reads the correct bitpattern, we don't need
	365	* to update it.
	366	*/
	367	if ((buf & mask) == (set & mask))
	368	return 0;
	369
	370	buf = (buf & ~mask) \| (set & mask);
	371	ret = rv3029_eeprom_write(dev, reg, &buf, 1);
	372	if (ret < 0)
	373	return ret;
	374
	375	return 0;
	376	}
	377
	378	static void rv3029_trickle_config(struct udevice *dev)
	379	{
	380	static const struct rv3029_trickle_tab_elem {
	381	u32 r; /* resistance in ohms */
	382	u8 conf; /* trickle config bits */
	383	} rv3029_trickle_tab[] = {
	384	{
	385	.r = 1076,
	386	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	387	RV3029_TRICKLE_20K \| RV3029_TRICKLE_80K,
	388	}, {
	389	.r = 1091,
	390	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	391	RV3029_TRICKLE_20K,
	392	}, {
	393	.r = 1137,
	394	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	395	RV3029_TRICKLE_80K,
	396	}, {
	397	.r = 1154,
	398	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K,
	399	}, {
	400	.r = 1371,
	401	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_20K \|
	402	RV3029_TRICKLE_80K,
	403	}, {
	404	.r = 1395,
	405	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_20K,
	406	}, {
	407	.r = 1472,
	408	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_80K,
409	}, {
410	.r = 1500,
411	.conf = RV3029_TRICKLE_1K,
412	}, {
413	.r = 3810,
414	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_20K \|
415	RV3029_TRICKLE_80K,
416	}, {
417	.r = 4000,
418	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_20K,
419	}, {
420	.r = 4706,
421	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_80K,
422	}, {
423	.r = 5000,
424	.conf = RV3029_TRICKLE_5K,
425	}, {
426	.r = 16000,
427	.conf = RV3029_TRICKLE_20K \| RV3029_TRICKLE_80K,
428	}, {
429	.r = 20000,
430	.conf = RV3029_TRICKLE_20K,
431	}, {
432	.r = 80000,
433	.conf = RV3029_TRICKLE_80K,
434	},
435	};
436	int err;
437	u32 ohms;
438	u8 trickle_set_bits = 0;
439
440	/* Configure the trickle charger. */
441	err = dev_read_u32(dev, "trickle-resistor-ohms", &ohms);
442
443	if (!err) {
444	/* Find trickle-charger config */
445	for (int i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++)
446	if (rv3029_trickle_tab[i].r >= ohms) {
447	dev_dbg(dev, "trickle charger at %d ohms\n",
448	rv3029_trickle_tab[i].r);
449	trickle_set_bits = rv3029_trickle_tab[i].conf;
450	break;
451	}
452	}
453
454	dev_dbg(dev, "trickle charger config 0x%x\n", trickle_set_bits);
455	err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
456	RV3029_TRICKLE_MASK,
457	trickle_set_bits);
458	if (err < 0)
459	dev_dbg(dev, "failed to update trickle charger\n");
460	}
461	#else
462	static inline void rv3029_trickle_config(struct udevice *dev)
463	{
464	}
71d19f30	465	#endif
a73610d2 PT	466
	467	static int rv3029_probe(struct udevice *dev)
	468	{
	469	i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS \|
	470	DM_I2C_CHIP_WR_ADDRESS);
	471
	472	rv3029_trickle_config(dev);
	473	return 0;
5c4fa2ee	474	}
a73610d2 PT	475
	476	static const struct rtc_ops rv3029_rtc_ops = {
	477	.get = rv3029_rtc_get,
	478	.set = rv3029_rtc_set,
	479	.read8 = rv3029_rtc_read8,
	480	.write8 = rv3029_rtc_write8,
	481	.reset = rv3029_rtc_reset,
	482	};
	483
	484	static const struct udevice_id rv3029_rtc_ids[] = {
	485	{ .compatible = "mc,rv3029" },
	486	{ .compatible = "mc,rv3029c2" },
	487	{ }
	488	};
	489
	490	U_BOOT_DRIVER(rtc_rv3029) = {
	491	.name = "rtc-rv3029",
	492	.id = UCLASS_RTC,
	493	.probe = rv3029_probe,
	494	.of_match = rv3029_rtc_ids,
	495	.ops = &rv3029_rtc_ops,
	496	};