drivers/power/supply/sbs-charger.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (c) 2016, Prodys S.L.
  *
  * This adds support for sbs-charger compilant chips as defined here:
  * http://sbs-forum.org/specs/sbc110.pdf
  *
  * Implemetation based on sbs-battery.c
  */

 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/err.h>
 #include <linux/power_supply.h>
 #include <linux/i2c.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/regmap.h>
 #include <linux/bitops.h>
 #include <linux/devm-helpers.h>

 #define SBS_CHARGER_REG_SPEC_INFO		0x11
 #define SBS_CHARGER_REG_STATUS			0x13
 #define SBS_CHARGER_REG_ALARM_WARNING		0x16

 #define SBS_CHARGER_STATUS_CHARGE_INHIBITED	BIT(0)
 #define SBS_CHARGER_STATUS_RES_COLD		BIT(9)
 #define SBS_CHARGER_STATUS_RES_HOT		BIT(10)
 #define SBS_CHARGER_STATUS_BATTERY_PRESENT	BIT(14)
 #define SBS_CHARGER_STATUS_AC_PRESENT		BIT(15)

 #define SBS_CHARGER_POLL_TIME			500

 struct sbs_info {
 	struct i2c_client		*client;
 	struct power_supply		*power_supply;
 	struct regmap			*regmap;
 	struct delayed_work		work;
 	unsigned int			last_state;
 };

 static int sbs_get_property(struct power_supply *psy,
 			    enum power_supply_property psp,
 			    union power_supply_propval *val)
 {
 	struct sbs_info *chip = power_supply_get_drvdata(psy);
 	unsigned int reg;

 	reg = chip->last_state;

 	switch (psp) {
 	case POWER_SUPPLY_PROP_PRESENT:
 		val->intval = !!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT);
 		break;

 	case POWER_SUPPLY_PROP_ONLINE:
 		val->intval = !!(reg & SBS_CHARGER_STATUS_AC_PRESENT);
 		break;

 	case POWER_SUPPLY_PROP_STATUS:
 		val->intval = POWER_SUPPLY_STATUS_UNKNOWN;

 		if (!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT))
 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 		else if (reg & SBS_CHARGER_STATUS_AC_PRESENT &&
 			 !(reg & SBS_CHARGER_STATUS_CHARGE_INHIBITED))
 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
 		else
 			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;

 		break;

 	case POWER_SUPPLY_PROP_HEALTH:
 		if (reg & SBS_CHARGER_STATUS_RES_COLD)
 			val->intval = POWER_SUPPLY_HEALTH_COLD;
 		if (reg & SBS_CHARGER_STATUS_RES_HOT)
 			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
 		else
 			val->intval = POWER_SUPPLY_HEALTH_GOOD;

 		break;

 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static int sbs_check_state(struct sbs_info *chip)
 {
 	unsigned int reg;
 	int ret;

 	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &reg);
 	if (!ret && reg != chip->last_state) {
 		chip->last_state = reg;
 		power_supply_changed(chip->power_supply);
 		return 1;
 	}

 	return 0;
 }

 static void sbs_delayed_work(struct work_struct *work)
 {
 	struct sbs_info *chip = container_of(work, struct sbs_info, work.work);

 	sbs_check_state(chip);

 	schedule_delayed_work(&chip->work,
 			      msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
 }

 static irqreturn_t sbs_irq_thread(int irq, void *data)
 {
 	struct sbs_info *chip = data;
 	int ret;

 	ret = sbs_check_state(chip);

 	return ret ? IRQ_HANDLED : IRQ_NONE;
 }

 static enum power_supply_property sbs_properties[] = {
 	POWER_SUPPLY_PROP_STATUS,
 	POWER_SUPPLY_PROP_PRESENT,
 	POWER_SUPPLY_PROP_ONLINE,
 	POWER_SUPPLY_PROP_HEALTH,
 };

 static bool sbs_readable_reg(struct device *dev, unsigned int reg)
 {
 	return reg >= SBS_CHARGER_REG_SPEC_INFO;
 }

 static bool sbs_volatile_reg(struct device *dev, unsigned int reg)
 {
 	switch (reg) {
 	case SBS_CHARGER_REG_STATUS:
 		return true;
 	}

 	return false;
 }

 static const struct regmap_config sbs_regmap = {
 	.reg_bits	= 8,
 	.val_bits	= 16,
 	.max_register	= SBS_CHARGER_REG_ALARM_WARNING,
 	.readable_reg	= sbs_readable_reg,
 	.volatile_reg	= sbs_volatile_reg,
 	.val_format_endian = REGMAP_ENDIAN_LITTLE, /* since based on SMBus */
 };

 static const struct power_supply_desc sbs_desc = {
 	.name = "sbs-charger",
 	.type = POWER_SUPPLY_TYPE_MAINS,
 	.properties = sbs_properties,
 	.num_properties = ARRAY_SIZE(sbs_properties),
 	.get_property = sbs_get_property,
 };

 static int sbs_probe(struct i2c_client *client)
 {
 	struct power_supply_config psy_cfg = {};
 	struct sbs_info *chip;
 	int ret, val;

 	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;

 	chip->client = client;
 	psy_cfg.of_node = client->dev.of_node;
 	psy_cfg.drv_data = chip;

 	i2c_set_clientdata(client, chip);

 	chip->regmap = devm_regmap_init_i2c(client, &sbs_regmap);
 	if (IS_ERR(chip->regmap))
 		return PTR_ERR(chip->regmap);

 	/*
 	 * Before we register, we need to make sure we can actually talk
 	 * to the battery.
 	 */
 	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &val);
 	if (ret)
 		return dev_err_probe(&client->dev, ret, "Failed to get device status\n");
 	chip->last_state = val;

 	chip->power_supply = devm_power_supply_register(&client->dev, &sbs_desc, &psy_cfg);
 	if (IS_ERR(chip->power_supply))
 		return dev_err_probe(&client->dev, PTR_ERR(chip->power_supply),
 				     "Failed to register power supply\n");

 	/*
 	 * The sbs-charger spec doesn't impose the use of an interrupt. So in
 	 * the case it wasn't provided we use polling in order get the charger's
 	 * status.
 	 */
 	if (client->irq) {
 		ret = devm_request_threaded_irq(&client->dev, client->irq,
 					NULL, sbs_irq_thread,
 					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 					dev_name(&client->dev), chip);
 		if (ret)
 			return dev_err_probe(&client->dev, ret, "Failed to request irq\n");
 	} else {
 		ret = devm_delayed_work_autocancel(&client->dev, &chip->work,
 						   sbs_delayed_work);
 		if (ret)
 			return dev_err_probe(&client->dev, ret,
 					     "Failed to init work for polling\n");

 		schedule_delayed_work(&chip->work,
 				      msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
 	}

 	dev_info(&client->dev,
 		 "%s: smart charger device registered\n", client->name);

 	return 0;
 }

 #ifdef CONFIG_OF
 static const struct of_device_id sbs_dt_ids[] = {
 	{ .compatible = "sbs,sbs-charger" },
 	{ },
 };
 MODULE_DEVICE_TABLE(of, sbs_dt_ids);
 #endif

 static const struct i2c_device_id sbs_id[] = {
 	{ "sbs-charger", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, sbs_id);

 static struct i2c_driver sbs_driver = {
 	.probe		= sbs_probe,
 	.id_table	= sbs_id,
 	.driver = {
 		.name	= "sbs-charger",
 		.of_match_table = of_match_ptr(sbs_dt_ids),
 	},
 };
 module_i2c_driver(sbs_driver);

 MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
 MODULE_DESCRIPTION("SBS smart charger driver");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* Copyright (c) 2016, Prodys S.L.
	*
	* This adds support for sbs-charger compilant chips as defined here:
	* http://sbs-forum.org/specs/sbc110.pdf
	*
	* Implemetation based on sbs-battery.c
	*/

	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/err.h>
	#include <linux/power_supply.h>
	#include <linux/i2c.h>
	#include <linux/slab.h>
	#include <linux/interrupt.h>
	#include <linux/regmap.h>
	#include <linux/bitops.h>
	#include <linux/devm-helpers.h>

	#define SBS_CHARGER_REG_SPEC_INFO 0x11
	#define SBS_CHARGER_REG_STATUS 0x13
	#define SBS_CHARGER_REG_ALARM_WARNING 0x16

	#define SBS_CHARGER_STATUS_CHARGE_INHIBITED BIT(0)
	#define SBS_CHARGER_STATUS_RES_COLD BIT(9)
	#define SBS_CHARGER_STATUS_RES_HOT BIT(10)
	#define SBS_CHARGER_STATUS_BATTERY_PRESENT BIT(14)
	#define SBS_CHARGER_STATUS_AC_PRESENT BIT(15)

	#define SBS_CHARGER_POLL_TIME 500

	struct sbs_info {
	struct i2c_client *client;
	struct power_supply *power_supply;
	struct regmap *regmap;
	struct delayed_work work;
	unsigned int last_state;
	};

	static int sbs_get_property(struct power_supply *psy,
	enum power_supply_property psp,
	union power_supply_propval *val)
	{
	struct sbs_info *chip = power_supply_get_drvdata(psy);
	unsigned int reg;

	reg = chip->last_state;

	switch (psp) {
	case POWER_SUPPLY_PROP_PRESENT:
	val->intval = !!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT);
	break;

	case POWER_SUPPLY_PROP_ONLINE:
	val->intval = !!(reg & SBS_CHARGER_STATUS_AC_PRESENT);
	break;

	case POWER_SUPPLY_PROP_STATUS:
	val->intval = POWER_SUPPLY_STATUS_UNKNOWN;

	if (!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT))
	val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
	else if (reg & SBS_CHARGER_STATUS_AC_PRESENT &&
	!(reg & SBS_CHARGER_STATUS_CHARGE_INHIBITED))
	val->intval = POWER_SUPPLY_STATUS_CHARGING;
	else
	val->intval = POWER_SUPPLY_STATUS_DISCHARGING;

	break;

	case POWER_SUPPLY_PROP_HEALTH:
	if (reg & SBS_CHARGER_STATUS_RES_COLD)
	val->intval = POWER_SUPPLY_HEALTH_COLD;
	if (reg & SBS_CHARGER_STATUS_RES_HOT)
	val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
	else
	val->intval = POWER_SUPPLY_HEALTH_GOOD;

	break;

	default:
	return -EINVAL;
	}

	return 0;
	}

	static int sbs_check_state(struct sbs_info *chip)
	{
	unsigned int reg;
	int ret;

	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &reg);
	if (!ret && reg != chip->last_state) {
	chip->last_state = reg;
	power_supply_changed(chip->power_supply);
	return 1;
	}

	return 0;
	}

	static void sbs_delayed_work(struct work_struct *work)
	{
	struct sbs_info *chip = container_of(work, struct sbs_info, work.work);

	sbs_check_state(chip);

	schedule_delayed_work(&chip->work,
	msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
	}

	static irqreturn_t sbs_irq_thread(int irq, void *data)
	{
	struct sbs_info *chip = data;
	int ret;

	ret = sbs_check_state(chip);

	return ret ? IRQ_HANDLED : IRQ_NONE;
	}

	static enum power_supply_property sbs_properties[] = {
	POWER_SUPPLY_PROP_STATUS,
	POWER_SUPPLY_PROP_PRESENT,
	POWER_SUPPLY_PROP_ONLINE,
	POWER_SUPPLY_PROP_HEALTH,
	};

	static bool sbs_readable_reg(struct device *dev, unsigned int reg)
	{
	return reg >= SBS_CHARGER_REG_SPEC_INFO;
	}

	static bool sbs_volatile_reg(struct device *dev, unsigned int reg)
	{
	switch (reg) {
	case SBS_CHARGER_REG_STATUS:
	return true;
	}

	return false;
	}

	static const struct regmap_config sbs_regmap = {
	.reg_bits = 8,
	.val_bits = 16,
	.max_register = SBS_CHARGER_REG_ALARM_WARNING,
	.readable_reg = sbs_readable_reg,
	.volatile_reg = sbs_volatile_reg,
	.val_format_endian = REGMAP_ENDIAN_LITTLE, /* since based on SMBus */
	};

	static const struct power_supply_desc sbs_desc = {
	.name = "sbs-charger",
	.type = POWER_SUPPLY_TYPE_MAINS,
	.properties = sbs_properties,
	.num_properties = ARRAY_SIZE(sbs_properties),
	.get_property = sbs_get_property,
	};

	static int sbs_probe(struct i2c_client *client)
	{
	struct power_supply_config psy_cfg = {};
	struct sbs_info *chip;
	int ret, val;

	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
	if (!chip)
	return -ENOMEM;

	chip->client = client;
	psy_cfg.of_node = client->dev.of_node;
	psy_cfg.drv_data = chip;

	i2c_set_clientdata(client, chip);

	chip->regmap = devm_regmap_init_i2c(client, &sbs_regmap);
	if (IS_ERR(chip->regmap))
	return PTR_ERR(chip->regmap);

	/*
	* Before we register, we need to make sure we can actually talk
	* to the battery.
	*/
	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &val);
	if (ret)
	return dev_err_probe(&client->dev, ret, "Failed to get device status\n");
	chip->last_state = val;

	chip->power_supply = devm_power_supply_register(&client->dev, &sbs_desc, &psy_cfg);
	if (IS_ERR(chip->power_supply))
	return dev_err_probe(&client->dev, PTR_ERR(chip->power_supply),
	"Failed to register power supply\n");

	/*
	* The sbs-charger spec doesn't impose the use of an interrupt. So in
	* the case it wasn't provided we use polling in order get the charger's
	* status.
	*/
	if (client->irq) {
	ret = devm_request_threaded_irq(&client->dev, client->irq,
	NULL, sbs_irq_thread,
	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	dev_name(&client->dev), chip);
	if (ret)
	return dev_err_probe(&client->dev, ret, "Failed to request irq\n");
	} else {
	ret = devm_delayed_work_autocancel(&client->dev, &chip->work,
	sbs_delayed_work);
	if (ret)
	return dev_err_probe(&client->dev, ret,
	"Failed to init work for polling\n");

	schedule_delayed_work(&chip->work,
	msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
	}

	dev_info(&client->dev,
	"%s: smart charger device registered\n", client->name);

	return 0;
	}

	#ifdef CONFIG_OF
	static const struct of_device_id sbs_dt_ids[] = {
	{ .compatible = "sbs,sbs-charger" },
	{ },
	};
	MODULE_DEVICE_TABLE(of, sbs_dt_ids);
	#endif

	static const struct i2c_device_id sbs_id[] = {
	{ "sbs-charger", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, sbs_id);

	static struct i2c_driver sbs_driver = {
	.probe = sbs_probe,
	.id_table = sbs_id,
	.driver = {
	.name = "sbs-charger",
	.of_match_table = of_match_ptr(sbs_dt_ids),
	},
	};
	module_i2c_driver(sbs_driver);

	MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
	MODULE_DESCRIPTION("SBS smart charger driver");
	MODULE_LICENSE("GPL v2");