forked from mirrors/linux
		
	 67075b63cc
			
		
	
	
		67075b63cc
		
	
	
	
	
		
			
			This patch adds support for AB-RTCMC-32.768kHz-EOZ9 RTC/Calendar module with I2C interface. Signed-off-by: Artem Panfilov <panfilov.artyom@gmail.com> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
		
			
				
	
	
		
			465 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			465 lines
		
	
	
	
		
			11 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
 | |
| /*
 | |
|  * Real Time Clock driver for AB-RTCMC-32.768kHz-EOZ9 chip.
 | |
|  * Copyright (C) 2019 Orolia
 | |
|  *
 | |
|  */
 | |
| 
 | |
| #include <linux/module.h>
 | |
| #include <linux/rtc.h>
 | |
| #include <linux/i2c.h>
 | |
| #include <linux/bcd.h>
 | |
| #include <linux/of.h>
 | |
| #include <linux/regmap.h>
 | |
| #include <linux/hwmon.h>
 | |
| #include <linux/hwmon-sysfs.h>
 | |
| 
 | |
| #define ABEOZ9_REG_CTRL1		0x00
 | |
| #define ABEOZ9_REG_CTRL1_MASK		GENMASK(7, 0)
 | |
| #define ABEOZ9_REG_CTRL1_WE		BIT(0)
 | |
| #define ABEOZ9_REG_CTRL1_TE		BIT(1)
 | |
| #define ABEOZ9_REG_CTRL1_TAR		BIT(2)
 | |
| #define ABEOZ9_REG_CTRL1_EERE		BIT(3)
 | |
| #define ABEOZ9_REG_CTRL1_SRON		BIT(4)
 | |
| #define ABEOZ9_REG_CTRL1_TD0		BIT(5)
 | |
| #define ABEOZ9_REG_CTRL1_TD1		BIT(6)
 | |
| #define ABEOZ9_REG_CTRL1_CLKINT		BIT(7)
 | |
| 
 | |
| #define ABEOZ9_REG_CTRL_INT		0x01
 | |
| #define ABEOZ9_REG_CTRL_INT_AIE		BIT(0)
 | |
| #define ABEOZ9_REG_CTRL_INT_TIE		BIT(1)
 | |
| #define ABEOZ9_REG_CTRL_INT_V1IE	BIT(2)
 | |
| #define ABEOZ9_REG_CTRL_INT_V2IE	BIT(3)
 | |
| #define ABEOZ9_REG_CTRL_INT_SRIE	BIT(4)
 | |
| 
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG	0x02
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG_AF	BIT(0)
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG_TF	BIT(1)
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG_V1IF	BIT(2)
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG_V2IF	BIT(3)
 | |
| #define ABEOZ9_REG_CTRL_INT_FLAG_SRF	BIT(4)
 | |
| 
 | |
| #define ABEOZ9_REG_CTRL_STATUS		0x03
 | |
| #define ABEOZ9_REG_CTRL_STATUS_V1F	BIT(2)
 | |
| #define ABEOZ9_REG_CTRL_STATUS_V2F	BIT(3)
 | |
| #define ABEOZ9_REG_CTRL_STATUS_SR	BIT(4)
 | |
| #define ABEOZ9_REG_CTRL_STATUS_PON	BIT(5)
 | |
| #define ABEOZ9_REG_CTRL_STATUS_EEBUSY	BIT(7)
 | |
| 
 | |
| #define ABEOZ9_REG_SEC			0x08
 | |
| #define ABEOZ9_REG_MIN			0x09
 | |
| #define ABEOZ9_REG_HOURS		0x0A
 | |
| #define ABEOZ9_HOURS_PM			BIT(6)
 | |
| #define ABEOZ9_REG_DAYS			0x0B
 | |
| #define ABEOZ9_REG_WEEKDAYS		0x0C
 | |
| #define ABEOZ9_REG_MONTHS		0x0D
 | |
| #define ABEOZ9_REG_YEARS		0x0E
 | |
| 
 | |
| #define ABEOZ9_SEC_LEN			7
 | |
| 
 | |
| #define ABEOZ9_REG_REG_TEMP		0x20
 | |
| #define ABEOZ953_TEMP_MAX		120
 | |
| #define ABEOZ953_TEMP_MIN		-60
 | |
| 
 | |
| #define ABEOZ9_REG_EEPROM		0x30
 | |
| #define ABEOZ9_REG_EEPROM_MASK		GENMASK(8, 0)
 | |
| #define ABEOZ9_REG_EEPROM_THP		BIT(0)
 | |
| #define ABEOZ9_REG_EEPROM_THE		BIT(1)
 | |
| #define ABEOZ9_REG_EEPROM_FD0		BIT(2)
 | |
| #define ABEOZ9_REG_EEPROM_FD1		BIT(3)
 | |
| #define ABEOZ9_REG_EEPROM_R1K		BIT(4)
 | |
| #define ABEOZ9_REG_EEPROM_R5K		BIT(5)
 | |
| #define ABEOZ9_REG_EEPROM_R20K		BIT(6)
 | |
| #define ABEOZ9_REG_EEPROM_R80K		BIT(7)
 | |
| 
 | |
| struct abeoz9_rtc_data {
 | |
| 	struct rtc_device *rtc;
 | |
| 	struct regmap *regmap;
 | |
| 	struct device *hwmon_dev;
 | |
| };
 | |
| 
 | |
| static int abeoz9_check_validity(struct device *dev)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 | |
| 	struct regmap *regmap = data->regmap;
 | |
| 	int ret;
 | |
| 	int val;
 | |
| 
 | |
| 	ret = regmap_read(regmap, ABEOZ9_REG_CTRL_STATUS, &val);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(dev,
 | |
| 			"unable to get CTRL_STATUS register (%d)\n", ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	if (val & ABEOZ9_REG_CTRL_STATUS_PON) {
 | |
| 		dev_warn(dev, "power-on reset detected, date is invalid\n");
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	if (val & ABEOZ9_REG_CTRL_STATUS_V1F) {
 | |
| 		dev_warn(dev,
 | |
| 			 "voltage drops below VLOW1 threshold, date is invalid\n");
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	if ((val & ABEOZ9_REG_CTRL_STATUS_V2F)) {
 | |
| 		dev_warn(dev,
 | |
| 			 "voltage drops below VLOW2 threshold, date is invalid\n");
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static int abeoz9_reset_validity(struct regmap *regmap)
 | |
| {
 | |
| 	return regmap_update_bits(regmap, ABEOZ9_REG_CTRL_STATUS,
 | |
| 				  ABEOZ9_REG_CTRL_STATUS_V1F |
 | |
| 				  ABEOZ9_REG_CTRL_STATUS_V2F |
 | |
| 				  ABEOZ9_REG_CTRL_STATUS_PON,
 | |
| 				  0);
 | |
| }
 | |
| 
 | |
| static int abeoz9_rtc_get_time(struct device *dev, struct rtc_time *tm)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 | |
| 	u8 regs[ABEOZ9_SEC_LEN];
 | |
| 	int ret;
 | |
| 
 | |
| 	ret = abeoz9_check_validity(dev);
 | |
| 	if (ret)
 | |
| 		return ret;
 | |
| 
 | |
| 	ret = regmap_bulk_read(data->regmap, ABEOZ9_REG_SEC,
 | |
| 			       regs,
 | |
| 			       sizeof(regs));
 | |
| 	if (ret) {
 | |
| 		dev_err(dev, "reading RTC time failed (%d)\n", ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	tm->tm_sec = bcd2bin(regs[ABEOZ9_REG_SEC - ABEOZ9_REG_SEC] & 0x7F);
 | |
| 	tm->tm_min = bcd2bin(regs[ABEOZ9_REG_MIN - ABEOZ9_REG_SEC] & 0x7F);
 | |
| 
 | |
| 	if (regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & ABEOZ9_HOURS_PM) {
 | |
| 		tm->tm_hour =
 | |
| 			bcd2bin(regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & 0x1f);
 | |
| 		if (regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] & ABEOZ9_HOURS_PM)
 | |
| 			tm->tm_hour += 12;
 | |
| 	} else {
 | |
| 		tm->tm_hour = bcd2bin(regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC]);
 | |
| 	}
 | |
| 
 | |
| 	tm->tm_mday = bcd2bin(regs[ABEOZ9_REG_DAYS - ABEOZ9_REG_SEC]);
 | |
| 	tm->tm_wday = bcd2bin(regs[ABEOZ9_REG_WEEKDAYS - ABEOZ9_REG_SEC]);
 | |
| 	tm->tm_mon  = bcd2bin(regs[ABEOZ9_REG_MONTHS - ABEOZ9_REG_SEC]) - 1;
 | |
| 	tm->tm_year = bcd2bin(regs[ABEOZ9_REG_YEARS - ABEOZ9_REG_SEC]) + 100;
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static int abeoz9_rtc_set_time(struct device *dev, struct rtc_time *tm)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 | |
| 	struct regmap *regmap = data->regmap;
 | |
| 	u8 regs[ABEOZ9_SEC_LEN];
 | |
| 	int ret;
 | |
| 
 | |
| 	regs[ABEOZ9_REG_SEC - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_sec);
 | |
| 	regs[ABEOZ9_REG_MIN - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_min);
 | |
| 	regs[ABEOZ9_REG_HOURS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_hour);
 | |
| 	regs[ABEOZ9_REG_DAYS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_mday);
 | |
| 	regs[ABEOZ9_REG_WEEKDAYS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_wday);
 | |
| 	regs[ABEOZ9_REG_MONTHS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_mon + 1);
 | |
| 	regs[ABEOZ9_REG_YEARS - ABEOZ9_REG_SEC] = bin2bcd(tm->tm_year - 100);
 | |
| 
 | |
| 	ret = regmap_bulk_write(data->regmap, ABEOZ9_REG_SEC,
 | |
| 				regs,
 | |
| 				sizeof(regs));
 | |
| 
 | |
| 	if (ret) {
 | |
| 		dev_err(dev, "set RTC time failed (%d)\n", ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	return abeoz9_reset_validity(regmap);
 | |
| }
 | |
| 
 | |
| static int abeoz9_trickle_parse_dt(struct device_node *node)
 | |
| {
 | |
| 	u32 ohms = 0;
 | |
| 
 | |
| 	if (of_property_read_u32(node, "trickle-resistor-ohms", &ohms))
 | |
| 		return 0;
 | |
| 
 | |
| 	switch (ohms) {
 | |
| 	case 1000:
 | |
| 		return ABEOZ9_REG_EEPROM_R1K;
 | |
| 	case 5000:
 | |
| 		return ABEOZ9_REG_EEPROM_R5K;
 | |
| 	case 20000:
 | |
| 		return ABEOZ9_REG_EEPROM_R20K;
 | |
| 	case 80000:
 | |
| 		return ABEOZ9_REG_EEPROM_R80K;
 | |
| 	default:
 | |
| 		return 0;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static int abeoz9_rtc_setup(struct device *dev, struct device_node *node)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 | |
| 	struct regmap *regmap = data->regmap;
 | |
| 	int ret;
 | |
| 
 | |
| 	/* Enable Self Recovery, Clock for Watch and EEPROM refresh functions */
 | |
| 	ret = regmap_update_bits(regmap, ABEOZ9_REG_CTRL1,
 | |
| 				 ABEOZ9_REG_CTRL1_MASK,
 | |
| 				 ABEOZ9_REG_CTRL1_WE |
 | |
| 				 ABEOZ9_REG_CTRL1_EERE |
 | |
| 				 ABEOZ9_REG_CTRL1_SRON);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(dev, "unable to set CTRL_1 register (%d)\n", ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	ret = regmap_write(regmap, ABEOZ9_REG_CTRL_INT, 0);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(dev,
 | |
| 			"unable to set control CTRL_INT register (%d)\n",
 | |
| 			ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	ret = regmap_write(regmap, ABEOZ9_REG_CTRL_INT_FLAG, 0);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(dev,
 | |
| 			"unable to set control CTRL_INT_FLAG register (%d)\n",
 | |
| 			ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	ret = abeoz9_trickle_parse_dt(node);
 | |
| 
 | |
| 	/* Enable built-in termometer */
 | |
| 	ret |= ABEOZ9_REG_EEPROM_THE;
 | |
| 
 | |
| 	ret = regmap_update_bits(regmap, ABEOZ9_REG_EEPROM,
 | |
| 				 ABEOZ9_REG_EEPROM_MASK,
 | |
| 				 ret);
 | |
| 	if (ret < 0) {
 | |
| 		dev_err(dev, "unable to set EEPROM register (%d)\n", ret);
 | |
| 		return ret;
 | |
| 	}
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static const struct rtc_class_ops rtc_ops = {
 | |
| 	.read_time = abeoz9_rtc_get_time,
 | |
| 	.set_time  = abeoz9_rtc_set_time,
 | |
| };
 | |
| 
 | |
| static const struct regmap_config abeoz9_rtc_regmap_config = {
 | |
| 	.reg_bits = 8,
 | |
| 	.val_bits = 8,
 | |
| };
 | |
| 
 | |
| #if IS_REACHABLE(CONFIG_HWMON)
 | |
| 
 | |
| static int abeoz9z3_temp_read(struct device *dev,
 | |
| 			      enum hwmon_sensor_types type,
 | |
| 			      u32 attr, int channel, long *temp)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = dev_get_drvdata(dev);
 | |
| 	struct regmap *regmap = data->regmap;
 | |
| 	int ret;
 | |
| 	unsigned int val;
 | |
| 
 | |
| 	ret = regmap_read(regmap, ABEOZ9_REG_CTRL_STATUS, &val);
 | |
| 	if (ret < 0)
 | |
| 		return ret;
 | |
| 
 | |
| 	if ((val & ABEOZ9_REG_CTRL_STATUS_V1F) ||
 | |
| 	    (val & ABEOZ9_REG_CTRL_STATUS_V2F)) {
 | |
| 		dev_err(dev,
 | |
| 			"thermometer might be disabled due to low voltage\n");
 | |
| 		return -EINVAL;
 | |
| 	}
 | |
| 
 | |
| 	switch (attr) {
 | |
| 	case hwmon_temp_input:
 | |
| 		ret = regmap_read(regmap, ABEOZ9_REG_REG_TEMP, &val);
 | |
| 		if (ret < 0)
 | |
| 			return ret;
 | |
| 		*temp = 1000 * (val + ABEOZ953_TEMP_MIN);
 | |
| 		return 0;
 | |
| 	case hwmon_temp_max:
 | |
| 		*temp = 1000 * ABEOZ953_TEMP_MAX;
 | |
| 		return 0;
 | |
| 	case hwmon_temp_min:
 | |
| 		*temp = 1000 * ABEOZ953_TEMP_MIN;
 | |
| 		return 0;
 | |
| 	default:
 | |
| 		return -EOPNOTSUPP;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static umode_t abeoz9_is_visible(const void *data,
 | |
| 				 enum hwmon_sensor_types type,
 | |
| 				 u32 attr, int channel)
 | |
| {
 | |
| 	switch (attr) {
 | |
| 	case hwmon_temp_input:
 | |
| 	case hwmon_temp_max:
 | |
| 	case hwmon_temp_min:
 | |
| 		return 0444;
 | |
| 	default:
 | |
| 		return 0;
 | |
| 	}
 | |
| }
 | |
| 
 | |
| static const u32 abeoz9_chip_config[] = {
 | |
| 	HWMON_C_REGISTER_TZ,
 | |
| 	0
 | |
| };
 | |
| 
 | |
| static const struct hwmon_channel_info abeoz9_chip = {
 | |
| 	.type = hwmon_chip,
 | |
| 	.config = abeoz9_chip_config,
 | |
| };
 | |
| 
 | |
| static const u32 abeoz9_temp_config[] = {
 | |
| 	HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN,
 | |
| 	0
 | |
| };
 | |
| 
 | |
| static const struct hwmon_channel_info abeoz9_temp = {
 | |
| 	.type = hwmon_temp,
 | |
| 	.config = abeoz9_temp_config,
 | |
| };
 | |
| 
 | |
| static const struct hwmon_channel_info *abeoz9_info[] = {
 | |
| 	&abeoz9_chip,
 | |
| 	&abeoz9_temp,
 | |
| 	NULL
 | |
| };
 | |
| 
 | |
| static const struct hwmon_ops abeoz9_hwmon_ops = {
 | |
| 	.is_visible = abeoz9_is_visible,
 | |
| 	.read = abeoz9z3_temp_read,
 | |
| };
 | |
| 
 | |
| static const struct hwmon_chip_info abeoz9_chip_info = {
 | |
| 	.ops = &abeoz9_hwmon_ops,
 | |
| 	.info = abeoz9_info,
 | |
| };
 | |
| 
 | |
| static void abeoz9_hwmon_register(struct device *dev,
 | |
| 				  struct abeoz9_rtc_data *data)
 | |
| {
 | |
| 	data->hwmon_dev =
 | |
| 		devm_hwmon_device_register_with_info(dev,
 | |
| 						     "abeoz9",
 | |
| 						     data,
 | |
| 						     &abeoz9_chip_info,
 | |
| 						     NULL);
 | |
| 	if (IS_ERR(data->hwmon_dev)) {
 | |
| 		dev_warn(dev, "unable to register hwmon device %ld\n",
 | |
| 			 PTR_ERR(data->hwmon_dev));
 | |
| 	}
 | |
| }
 | |
| 
 | |
| #else
 | |
| 
 | |
| static void abeoz9_hwmon_register(struct device *dev,
 | |
| 				  struct abeoz9_rtc_data *data)
 | |
| {
 | |
| }
 | |
| 
 | |
| #endif
 | |
| 
 | |
| static int abeoz9_probe(struct i2c_client *client,
 | |
| 			const struct i2c_device_id *id)
 | |
| {
 | |
| 	struct abeoz9_rtc_data *data = NULL;
 | |
| 	struct device *dev = &client->dev;
 | |
| 	struct regmap *regmap;
 | |
| 	int ret;
 | |
| 
 | |
| 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
 | |
| 				     I2C_FUNC_SMBUS_BYTE_DATA |
 | |
| 				     I2C_FUNC_SMBUS_I2C_BLOCK)) {
 | |
| 		ret = -ENODEV;
 | |
| 		goto err;
 | |
| 	}
 | |
| 
 | |
| 	regmap = devm_regmap_init_i2c(client, &abeoz9_rtc_regmap_config);
 | |
| 	if (IS_ERR(regmap)) {
 | |
| 		ret = PTR_ERR(regmap);
 | |
| 		dev_err(dev, "regmap allocation failed: %d\n", ret);
 | |
| 		goto err;
 | |
| 	}
 | |
| 
 | |
| 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 | |
| 	if (!data) {
 | |
| 		ret = -ENOMEM;
 | |
| 		goto err;
 | |
| 	}
 | |
| 
 | |
| 	data->regmap = regmap;
 | |
| 	dev_set_drvdata(dev, data);
 | |
| 
 | |
| 	ret = abeoz9_rtc_setup(dev, client->dev.of_node);
 | |
| 	if (ret)
 | |
| 		goto err;
 | |
| 
 | |
| 	data->rtc = devm_rtc_allocate_device(dev);
 | |
| 	ret = PTR_ERR_OR_ZERO(data->rtc);
 | |
| 	if (ret)
 | |
| 		goto err;
 | |
| 
 | |
| 	data->rtc->ops = &rtc_ops;
 | |
| 	data->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;
 | |
| 	data->rtc->range_max = RTC_TIMESTAMP_END_2099;
 | |
| 
 | |
| 	ret = rtc_register_device(data->rtc);
 | |
| 	if (ret)
 | |
| 		goto err;
 | |
| 
 | |
| 	abeoz9_hwmon_register(dev, data);
 | |
| 	return 0;
 | |
| 
 | |
| err:
 | |
| 	dev_err(dev, "unable to register RTC device (%d)\n", ret);
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_OF
 | |
| static const struct of_device_id abeoz9_dt_match[] = {
 | |
| 	{ .compatible = "abracon,abeoz9" },
 | |
| 	{ },
 | |
| };
 | |
| MODULE_DEVICE_TABLE(of, abeoz9_dt_match);
 | |
| #endif
 | |
| 
 | |
| static const struct i2c_device_id abeoz9_id[] = {
 | |
| 	{ "abeoz9", 0 },
 | |
| 	{ }
 | |
| };
 | |
| 
 | |
| static struct i2c_driver abeoz9_driver = {
 | |
| 	.driver = {
 | |
| 		.name = "rtc-ab-eoz9",
 | |
| 		.of_match_table = of_match_ptr(abeoz9_dt_match),
 | |
| 	},
 | |
| 	.probe	  = abeoz9_probe,
 | |
| 	.id_table = abeoz9_id,
 | |
| };
 | |
| 
 | |
| module_i2c_driver(abeoz9_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Artem Panfilov <panfilov.artyom@gmail.com>");
 | |
| MODULE_DESCRIPTION("Abracon AB-RTCMC-32.768kHz-EOZ9 RTC driver");
 | |
| MODULE_LICENSE("GPL");
 |