[thirdparty/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 <gregory.hermant@calao-systems.com>
 *   Michael Buesch <m@bues.ch>
 */

#include <common.h>
#include <command.h>
#include <dm.h>
#include <eeprom.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 <gregory.hermant@calao-systems.com>
	7	* Michael Buesch <m@bues.ch>
5c4fa2ee	8	*/
a73610d2	9
d678a59d	10	#include <common.h>
5c4fa2ee	11	#include <command.h>
a73610d2	12	#include <dm.h>
d678a59d	13	#include <eeprom.h>
5c4fa2ee	14	#include <i2c.h>
f7ae49fc	15	#include <log.h>
5c4fa2ee	16	#include <rtc.h>
336d4615	17	#include <dm/device_compat.h>
cd93d625	18	#include <linux/bitops.h>
c05ed00a	19	#include <linux/delay.h>
5c4fa2ee	20
a73610d2	21	#define RTC_RV3029_PAGE_LEN 7
71d19f30	22
a73610d2 PT	23	/* control section */
	24	#define RV3029_ONOFF_CTRL 0x00
	25	#define RV3029_ONOFF_CTRL_WE BIT(0)
	26	#define RV3029_ONOFF_CTRL_TE BIT(1)
	27	#define RV3029_ONOFF_CTRL_TAR BIT(2)
	28	#define RV3029_ONOFF_CTRL_EERE BIT(3)
	29	#define RV3029_ONOFF_CTRL_SRON BIT(4)
	30	#define RV3029_ONOFF_CTRL_TD0 BIT(5)
	31	#define RV3029_ONOFF_CTRL_TD1 BIT(6)
	32	#define RV3029_ONOFF_CTRL_CLKINT BIT(7)
	33	#define RV3029_IRQ_CTRL 0x01
	34	#define RV3029_IRQ_CTRL_AIE BIT(0)
	35	#define RV3029_IRQ_CTRL_TIE BIT(1)
	36	#define RV3029_IRQ_CTRL_V1IE BIT(2)
	37	#define RV3029_IRQ_CTRL_V2IE BIT(3)
	38	#define RV3029_IRQ_CTRL_SRIE BIT(4)
	39	#define RV3029_IRQ_FLAGS 0x02
	40	#define RV3029_IRQ_FLAGS_AF BIT(0)
	41	#define RV3029_IRQ_FLAGS_TF BIT(1)
	42	#define RV3029_IRQ_FLAGS_V1IF BIT(2)
	43	#define RV3029_IRQ_FLAGS_V2IF BIT(3)
	44	#define RV3029_IRQ_FLAGS_SRF BIT(4)
	45	#define RV3029_STATUS 0x03
	46	#define RV3029_STATUS_VLOW1 BIT(2)
	47	#define RV3029_STATUS_VLOW2 BIT(3)
	48	#define RV3029_STATUS_SR BIT(4)
	49	#define RV3029_STATUS_PON BIT(5)
	50	#define RV3029_STATUS_EEBUSY BIT(7)
	51	#define RV3029_RST_CTRL 0x04
	52	#define RV3029_RST_CTRL_SYSR BIT(4)
	53	#define RV3029_CONTROL_SECTION_LEN 0x05
5c4fa2ee	54
a73610d2 PT	55	/* watch section */
	56	#define RV3029_W_SEC 0x08
	57	#define RV3029_W_MINUTES 0x09
	58	#define RV3029_W_HOURS 0x0A
	59	#define RV3029_REG_HR_12_24 BIT(6) /* 24h/12h mode */
	60	#define RV3029_REG_HR_PM BIT(5) /* PM/AM bit in 12h mode */
	61	#define RV3029_W_DATE 0x0B
	62	#define RV3029_W_DAYS 0x0C
	63	#define RV3029_W_MONTHS 0x0D
	64	#define RV3029_W_YEARS 0x0E
5c4fa2ee	65
a73610d2 PT	66	/* eeprom control section */
	67	#define RV3029_CONTROL_E2P_EECTRL 0x30
	68	#define RV3029_TRICKLE_1K BIT(4) /* 1.5K resistance */
	69	#define RV3029_TRICKLE_5K BIT(5) /* 5K resistance */
	70	#define RV3029_TRICKLE_20K BIT(6) /* 20K resistance */
	71	#define RV3029_TRICKLE_80K BIT(7) /* 80K resistance */
	72	#define RV3029_TRICKLE_MASK (RV3029_TRICKLE_1K \|\
	73	RV3029_TRICKLE_5K \|\
	74	RV3029_TRICKLE_20K \|\
	75	RV3029_TRICKLE_80K)
	76	#define RV3029_TRICKLE_SHIFT 4
5c4fa2ee	77
5c4fa2ee	78
a73610d2	79	static int rv3029_rtc_get(struct udevice dev, struct rtc_time tm)
5c4fa2ee	80	{
a73610d2 PT	81	u8 regs[RTC_RV3029_PAGE_LEN];
a73610d2 PT	82	int ret;
5c4fa2ee	83
a73610d2 PT	84	ret = dm_i2c_read(dev, RV3029_W_SEC, regs, sizeof(regs));
a73610d2 PT	85	if (ret < 0) {
5c4fa2ee	86	printf("%s: error reading RTC: %x\n", __func__, ret);
a73610d2 PT	87	return -EIO;
	88	}
	89
	90	tm->tm_sec = bcd2bin(regs[RV3029_W_SEC - RV3029_W_SEC]);
	91	tm->tm_min = bcd2bin(regs[RV3029_W_MINUTES - RV3029_W_SEC]);
	92
	93	/* HR field has a more complex interpretation */
	94	{
	95	const u8 _hr = regs[RV3029_W_HOURS - RV3029_W_SEC];
	96
	97	if (_hr & RV3029_REG_HR_12_24) {
	98	/* 12h format */
	99	tm->tm_hour = bcd2bin(_hr & 0x1f);
	100	if (_hr & RV3029_REG_HR_PM) /* PM flag set */
	101	tm->tm_hour += 12;
	102	} else {
	103	/* 24h format */
	104	tm->tm_hour = bcd2bin(_hr & 0x3f);
	105	}
5c4fa2ee	106	}
a73610d2 PT	107
	108	tm->tm_mday = bcd2bin(regs[RV3029_W_DATE - RV3029_W_SEC]);
	109	tm->tm_mon = bcd2bin(regs[RV3029_W_MONTHS - RV3029_W_SEC]) - 1;
5c4fa2ee	110	/* RTC supports only years > 1999 */
a73610d2 PT	111	tm->tm_year = bcd2bin(regs[RV3029_W_YEARS - RV3029_W_SEC]) + 2000;
	112	tm->tm_wday = bcd2bin(regs[RV3029_W_DAYS - RV3029_W_SEC]) - 1;
	113
	114	tm->tm_yday = 0;
	115	tm->tm_isdst = 0;
5c4fa2ee	116
a73610d2 PT	117	debug("%s: %4d-%02d-%02d (wday=%d) %2d:%02d:%02d\n",
	118	__func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	119	tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
5c4fa2ee	120
5c4fa2ee HS	121	return 0;
	122	}
	123
a73610d2	124	static int rv3029_rtc_set(struct udevice dev, const struct rtc_time tm)
5c4fa2ee	125	{
a73610d2 PT	126	u8 regs[RTC_RV3029_PAGE_LEN];
	127
	128	debug("%s: %4d-%02d-%02d (wday=%d( %2d:%02d:%02d\n",
	129	__func__, tm->tm_year, tm->tm_mon, tm->tm_mday,
	130	tm->tm_wday, tm->tm_hour, tm->tm_min, tm->tm_sec);
b633741b	131
5c4fa2ee	132
a73610d2 PT	133	if (tm->tm_year < 2000) {
	134	printf("%s: year %d (before 2000) not supported\n",
	135	__func__, tm->tm_year);
	136	return -EINVAL;
5c4fa2ee	137	}
a73610d2 PT	138
	139	regs[RV3029_W_SEC - RV3029_W_SEC] = bin2bcd(tm->tm_sec);
	140	regs[RV3029_W_MINUTES - RV3029_W_SEC] = bin2bcd(tm->tm_min);
	141	regs[RV3029_W_HOURS - RV3029_W_SEC] = bin2bcd(tm->tm_hour);
	142	regs[RV3029_W_DATE - RV3029_W_SEC] = bin2bcd(tm->tm_mday);
	143	regs[RV3029_W_MONTHS - RV3029_W_SEC] = bin2bcd(tm->tm_mon + 1);
	144	regs[RV3029_W_DAYS - RV3029_W_SEC] = bin2bcd(tm->tm_wday + 1) & 0x7;
	145	regs[RV3029_W_YEARS - RV3029_W_SEC] = bin2bcd(tm->tm_year - 2000);
	146
	147	return dm_i2c_write(dev, RV3029_W_SEC, regs, sizeof(regs));
5c4fa2ee HS	148	}
5c4fa2ee HS	149
a73610d2	150	static int rv3029_rtc_reset(struct udevice *dev)
71d19f30	151	{
a73610d2 PT	152	u8 ctrl = RV3029_RST_CTRL_SYSR;
	153	unsigned long start;
	154	const unsigned long timeout_ms = 10000;
	155	int ret;
71d19f30	156
a73610d2 PT	157	/* trigger the system-reset */
	158	ret = dm_i2c_write(dev, RV3029_RST_CTRL, &ctrl, 1);
	159	if (ret < 0)
	160	return -EIO;
71d19f30	161
a73610d2 PT	162	/* wait for the system-reset to complete */
	163	start = get_timer(0);
	164	do {
	165	if (get_timer(start) > timeout_ms)
	166	return -ETIMEDOUT;
71d19f30	167
a73610d2 PT	168	ret = dm_i2c_read(dev, RV3029_RST_CTRL, &ctrl, 1);
	169	if (ret < 0)
	170	return -EIO;
	171	} while (ctrl & RV3029_RST_CTRL_SYSR);
	172
	173	return 0;
71d19f30 HS	174	}
71d19f30 HS	175
a73610d2	176	static int rv3029_rtc_read8(struct udevice *dev, unsigned int reg)
71d19f30	177	{
a73610d2 PT	178	u8 data;
	179	int ret;
	180
	181	ret = dm_i2c_read(dev, reg, &data, sizeof(data));
	182	return ret < 0 ? ret : data;
	183	}
71d19f30	184
a73610d2 PT	185	static int rv3029_rtc_write8(struct udevice *dev, unsigned int reg, int val)
	186	{
	187	u8 data = val;
	188
	189	return dm_i2c_write(dev, reg, &data, 1);
	190	}
	191
	192	#if defined(OF_CONTROL)
	193	static int rv3029_get_sr(struct udevice dev, u8 buf)
	194	{
	195	int ret = dm_i2c_read(dev, RV3029_STATUS, buf, 1);
	196
	197	if (ret < 0)
	198	return -EIO;
	199
	200	dev_dbg(dev, "status = 0x%.2x (%d)\n", buf[0], buf[0]);
	201	return 0;
	202	}
71d19f30	203
a73610d2 PT	204	static int rv3029_set_sr(struct udevice *dev, u8 val)
	205	{
	206	int ret;
	207
	208	ret = dm_i2c_read(dev, RV3029_STATUS, &val, 1);
	209	if (ret < 0)
	210	return -EIO;
	211
	212	dev_dbg(dev, "status = 0x%.2x (%d)\n", val, val);
	213	return 0;
	214	}
	215
	216	static int rv3029_eeprom_busywait(struct udevice *dev)
	217	{
	218	int i, ret;
	219	u8 sr;
	220
	221	for (i = 100; i > 0; i--) {
	222	ret = rv3029_get_sr(dev, &sr);
	223	if (ret < 0)
	224	break;
	225	if (!(sr & RV3029_STATUS_EEBUSY))
71d19f30 HS	226	break;
	227	udelay(10000);
	228	}
a73610d2 PT	229	if (i <= 0) {
	230	dev_err(dev, "EEPROM busy wait timeout.\n");
	231	return -ETIMEDOUT;
	232	}
	233
	234	return ret;
71d19f30 HS	235	}
71d19f30 HS	236
a73610d2	237	static int rv3029_update_bits(struct udevice *dev, u8 reg, u8 mask, u8 set)
5c4fa2ee	238	{
a73610d2 PT	239	u8 buf;
a73610d2 PT	240	int ret;
5c4fa2ee	241
a73610d2 PT	242	ret = dm_i2c_read(dev, reg, &buf, 1);
	243	if (ret < 0)
	244	return ret;
71d19f30	245
a73610d2 PT	246	if ((buf & mask) == (set && mask))
a73610d2 PT	247	return 0;
71d19f30	248
a73610d2 PT	249	buf = (buf & ~mask) \| (set & mask);
	250	ret = dm_i2c_read(dev, reg, &buf, 1);
	251	if (ret < 0)
	252	return ret;
	253
	254	return 0;
	255	}
	256
	257	static int rv3029_eeprom_exit(struct udevice *dev)
	258	{
	259	/* Re-enable eeprom refresh */
	260	return rv3029_update_bits(dev, RV3029_ONOFF_CTRL,
	261	RV3029_ONOFF_CTRL_EERE,
	262	RV3029_ONOFF_CTRL_EERE);
	263	}
	264
	265	static int rv3029_eeprom_enter(struct udevice *dev)
	266	{
	267	int ret;
	268	u8 sr;
	269
	270	/* Check whether we are in the allowed voltage range. */
	271	ret = rv3029_get_sr(dev, &sr);
	272	if (ret < 0)
	273	return ret;
	274	if (sr & (RV3029_STATUS_VLOW1 \| RV3029_STATUS_VLOW2)) {
	275	/* We clear the bits and retry once just in case
	276	* we had a brown out in early startup.
71d19f30	277	*/
a73610d2 PT	278	sr &= ~RV3029_STATUS_VLOW1;
	279	sr &= ~RV3029_STATUS_VLOW2;
	280	ret = rv3029_set_sr(dev, sr);
	281	if (ret < 0)
	282	return ret;
71d19f30	283	udelay(10000);
a73610d2 PT	284	ret = rv3029_get_sr(dev, &sr);
	285	if (ret < 0)
	286	return ret;
	287	if (sr & (RV3029_STATUS_VLOW1 \| RV3029_STATUS_VLOW2)) {
	288	dev_err(dev, "Supply voltage is too low to safely access the EEPROM.\n");
	289	return -ENODEV;
	290	}
	291	}
	292
	293	/* Disable eeprom refresh. */
	294	ret = rv3029_update_bits(dev,
	295	RV3029_ONOFF_CTRL, RV3029_ONOFF_CTRL_EERE, 0);
	296	if (ret < 0)
	297	return ret;
	298
	299	/* Wait for any previous eeprom accesses to finish. */
	300	ret = rv3029_eeprom_busywait(dev);
	301	if (ret < 0)
	302	rv3029_eeprom_exit(dev);
	303
	304	return ret;
	305	}
	306
	307	static int rv3029_eeprom_read(struct udevice *dev, u8 reg,
	308	u8 buf[], size_t len)
	309	{
	310	int ret, err;
	311
	312	err = rv3029_eeprom_enter(dev);
	313	if (err < 0)
	314	return err;
	315
	316	ret = dm_i2c_read(dev, reg, buf, len);
	317
	318	err = rv3029_eeprom_exit(dev);
	319	if (err < 0)
	320	return err;
	321
	322	return ret;
	323	}
	324
	325	static int rv3029_eeprom_write(struct udevice *dev, u8 reg,
	326	u8 const buf[], size_t len)
	327	{
	328	int ret;
	329	size_t i;
	330	u8 tmp;
	331
	332	ret = rv3029_eeprom_enter(dev);
	333	if (ret < 0)
	334	return ret;
	335
	336	for (i = 0; i < len; i++, reg++) {
	337	ret = dm_i2c_read(dev, reg, &tmp, 1);
	338	if (ret < 0)
	339	break;
	340	if (tmp != buf[i]) {
	341	ret = dm_i2c_write(dev, reg, &buf[i], 1);
	342	if (ret < 0)
	343	break;
	344	}
	345	ret = rv3029_eeprom_busywait(dev);
	346	if (ret < 0)
	347	break;
71d19f30	348	}
a73610d2 PT	349
	350	ret = rv3029_eeprom_exit(dev);
	351	if (ret < 0)
	352	return ret;
	353
	354	return 0;
	355	}
	356
	357	static int rv3029_eeprom_update_bits(struct udevice *dev,
	358	u8 reg, u8 mask, u8 set)
	359	{
	360	u8 buf;
	361	int ret;
	362
	363	ret = rv3029_eeprom_read(dev, reg, &buf, 1);
	364	if (ret < 0)
	365	return ret;
	366
	367	/*
	368	* If the EEPROM already reads the correct bitpattern, we don't need
	369	* to update it.
	370	*/
	371	if ((buf & mask) == (set & mask))
	372	return 0;
	373
	374	buf = (buf & ~mask) \| (set & mask);
	375	ret = rv3029_eeprom_write(dev, reg, &buf, 1);
	376	if (ret < 0)
	377	return ret;
	378
	379	return 0;
	380	}
	381
	382	static void rv3029_trickle_config(struct udevice *dev)
	383	{
	384	static const struct rv3029_trickle_tab_elem {
	385	u32 r; /* resistance in ohms */
	386	u8 conf; /* trickle config bits */
	387	} rv3029_trickle_tab[] = {
	388	{
	389	.r = 1076,
	390	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	391	RV3029_TRICKLE_20K \| RV3029_TRICKLE_80K,
	392	}, {
	393	.r = 1091,
	394	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	395	RV3029_TRICKLE_20K,
	396	}, {
	397	.r = 1137,
	398	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K \|
	399	RV3029_TRICKLE_80K,
	400	}, {
	401	.r = 1154,
	402	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_5K,
	403	}, {
	404	.r = 1371,
	405	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_20K \|
	406	RV3029_TRICKLE_80K,
	407	}, {
	408	.r = 1395,
	409	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_20K,
	410	}, {
	411	.r = 1472,
	412	.conf = RV3029_TRICKLE_1K \| RV3029_TRICKLE_80K,
413	}, {
414	.r = 1500,
415	.conf = RV3029_TRICKLE_1K,
416	}, {
417	.r = 3810,
418	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_20K \|
419	RV3029_TRICKLE_80K,
420	}, {
421	.r = 4000,
422	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_20K,
423	}, {
424	.r = 4706,
425	.conf = RV3029_TRICKLE_5K \| RV3029_TRICKLE_80K,
426	}, {
427	.r = 5000,
428	.conf = RV3029_TRICKLE_5K,
429	}, {
430	.r = 16000,
431	.conf = RV3029_TRICKLE_20K \| RV3029_TRICKLE_80K,
432	}, {
433	.r = 20000,
434	.conf = RV3029_TRICKLE_20K,
435	}, {
436	.r = 80000,
437	.conf = RV3029_TRICKLE_80K,
438	},
439	};
440	int err;
441	u32 ohms;
442	u8 trickle_set_bits = 0;
443
444	/* Configure the trickle charger. */
445	err = dev_read_u32(dev, "trickle-resistor-ohms", &ohms);
446
447	if (!err) {
448	/* Find trickle-charger config */
449	for (int i = 0; i < ARRAY_SIZE(rv3029_trickle_tab); i++)
450	if (rv3029_trickle_tab[i].r >= ohms) {
451	dev_dbg(dev, "trickle charger at %d ohms\n",
452	rv3029_trickle_tab[i].r);
453	trickle_set_bits = rv3029_trickle_tab[i].conf;
454	break;
455	}
456	}
457
458	dev_dbg(dev, "trickle charger config 0x%x\n", trickle_set_bits);
459	err = rv3029_eeprom_update_bits(dev, RV3029_CONTROL_E2P_EECTRL,
460	RV3029_TRICKLE_MASK,
461	trickle_set_bits);
462	if (err < 0)
463	dev_dbg(dev, "failed to update trickle charger\n");
464	}
465	#else
466	static inline void rv3029_trickle_config(struct udevice *dev)
467	{
468	}
71d19f30	469	#endif
a73610d2 PT	470
	471	static int rv3029_probe(struct udevice *dev)
	472	{
	473	i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS \|
	474	DM_I2C_CHIP_WR_ADDRESS);
	475
	476	rv3029_trickle_config(dev);
	477	return 0;
5c4fa2ee	478	}
a73610d2 PT	479
	480	static const struct rtc_ops rv3029_rtc_ops = {
	481	.get = rv3029_rtc_get,
	482	.set = rv3029_rtc_set,
	483	.read8 = rv3029_rtc_read8,
	484	.write8 = rv3029_rtc_write8,
	485	.reset = rv3029_rtc_reset,
	486	};
	487
	488	static const struct udevice_id rv3029_rtc_ids[] = {
	489	{ .compatible = "mc,rv3029" },
	490	{ .compatible = "mc,rv3029c2" },
	491	{ }
	492	};
	493
	494	U_BOOT_DRIVER(rtc_rv3029) = {
	495	.name = "rtc-rv3029",
	496	.id = UCLASS_RTC,
	497	.probe = rv3029_probe,
	498	.of_match = rv3029_rtc_ids,
	499	.ops = &rv3029_rtc_ops,
	500	};