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