[linux-2.6-block.git] / drivers / power / supply / sbs-charger.c

// 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>

#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(1)
#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,
		     const struct i2c_device_id *id)
{
	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 {
		INIT_DELAYED_WORK(&chip->work, sbs_delayed_work);
		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;
}

static int sbs_remove(struct i2c_client *client)
{
	struct sbs_info *chip = i2c_get_clientdata(client);

	cancel_delayed_work_sync(&chip->work);

	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,
	.remove		= sbs_remove,
	.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");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
feb583e3 NSJ	2	/*
	3	* Copyright (c) 2016, Prodys S.L.
	4	*
feb583e3 NSJ	5	* This adds support for sbs-charger compilant chips as defined here:
	6	* http://sbs-forum.org/specs/sbc110.pdf
	7	*
	8	* Implemetation based on sbs-battery.c
	9	*/
	10
	11	#include <linux/init.h>
	12	#include <linux/module.h>
	13	#include <linux/kernel.h>
	14	#include <linux/err.h>
	15	#include <linux/power_supply.h>
	16	#include <linux/i2c.h>
	17	#include <linux/slab.h>
	18	#include <linux/interrupt.h>
feb583e3	19	#include <linux/regmap.h>
feb583e3 NSJ	20	#include <linux/bitops.h>
	21
	22	#define SBS_CHARGER_REG_SPEC_INFO 0x11
	23	#define SBS_CHARGER_REG_STATUS 0x13
	24	#define SBS_CHARGER_REG_ALARM_WARNING 0x16
	25
	26	#define SBS_CHARGER_STATUS_CHARGE_INHIBITED BIT(1)
	27	#define SBS_CHARGER_STATUS_RES_COLD BIT(9)
	28	#define SBS_CHARGER_STATUS_RES_HOT BIT(10)
	29	#define SBS_CHARGER_STATUS_BATTERY_PRESENT BIT(14)
	30	#define SBS_CHARGER_STATUS_AC_PRESENT BIT(15)
	31
	32	#define SBS_CHARGER_POLL_TIME 500
	33
	34	struct sbs_info {
	35	struct i2c_client *client;
	36	struct power_supply *power_supply;
	37	struct regmap *regmap;
	38	struct delayed_work work;
	39	unsigned int last_state;
	40	};
	41
	42	static int sbs_get_property(struct power_supply *psy,
	43	enum power_supply_property psp,
	44	union power_supply_propval *val)
	45	{
	46	struct sbs_info *chip = power_supply_get_drvdata(psy);
	47	unsigned int reg;
	48
	49	reg = chip->last_state;
	50
	51	switch (psp) {
	52	case POWER_SUPPLY_PROP_PRESENT:
	53	val->intval = !!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT);
	54	break;
	55
	56	case POWER_SUPPLY_PROP_ONLINE:
	57	val->intval = !!(reg & SBS_CHARGER_STATUS_AC_PRESENT);
	58	break;
	59
	60	case POWER_SUPPLY_PROP_STATUS:
	61	val->intval = POWER_SUPPLY_STATUS_UNKNOWN;
	62
	63	if (!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT))
	64	val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
	65	else if (reg & SBS_CHARGER_STATUS_AC_PRESENT &&
	66	!(reg & SBS_CHARGER_STATUS_CHARGE_INHIBITED))
	67	val->intval = POWER_SUPPLY_STATUS_CHARGING;
	68	else
	69	val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
	70
	71	break;
	72
	73	case POWER_SUPPLY_PROP_HEALTH:
	74	if (reg & SBS_CHARGER_STATUS_RES_COLD)
	75	val->intval = POWER_SUPPLY_HEALTH_COLD;
	76	if (reg & SBS_CHARGER_STATUS_RES_HOT)
	77	val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
	78	else
	79	val->intval = POWER_SUPPLY_HEALTH_GOOD;
	80
	81	break;
	82
	83	default:
84	return -EINVAL;
85	}
86
87	return 0;
88	}
89
90	static int sbs_check_state(struct sbs_info *chip)
91	{
92	unsigned int reg;
93	int ret;
94
95	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &reg);
96	if (!ret && reg != chip->last_state) {
97	chip->last_state = reg;
98	power_supply_changed(chip->power_supply);
99	return 1;
100	}
101
102	return 0;
103	}
104
105	static void sbs_delayed_work(struct work_struct *work)
106	{
107	struct sbs_info *chip = container_of(work, struct sbs_info, work.work);
108
109	sbs_check_state(chip);
110
111	schedule_delayed_work(&chip->work,
112	msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
113	}
114
115	static irqreturn_t sbs_irq_thread(int irq, void *data)
116	{
117	struct sbs_info *chip = data;
118	int ret;
119
120	ret = sbs_check_state(chip);
121
122	return ret ? IRQ_HANDLED : IRQ_NONE;
123	}
124
125	static enum power_supply_property sbs_properties[] = {
126	POWER_SUPPLY_PROP_STATUS,
127	POWER_SUPPLY_PROP_PRESENT,
128	POWER_SUPPLY_PROP_ONLINE,
129	POWER_SUPPLY_PROP_HEALTH,
130	};
131
132	static bool sbs_readable_reg(struct device *dev, unsigned int reg)
133	{
dba83476	134	return reg >= SBS_CHARGER_REG_SPEC_INFO;
feb583e3 NSJ	135	}
	136
	137	static bool sbs_volatile_reg(struct device *dev, unsigned int reg)
	138	{
	139	switch (reg) {
	140	case SBS_CHARGER_REG_STATUS:
	141	return true;
	142	}
	143
	144	return false;
	145	}
	146
	147	static const struct regmap_config sbs_regmap = {
	148	.reg_bits = 8,
	149	.val_bits = 16,
	150	.max_register = SBS_CHARGER_REG_ALARM_WARNING,
	151	.readable_reg = sbs_readable_reg,
	152	.volatile_reg = sbs_volatile_reg,
	153	.val_format_endian = REGMAP_ENDIAN_LITTLE, /* since based on SMBus */
	154	};
	155
	156	static const struct power_supply_desc sbs_desc = {
	157	.name = "sbs-charger",
	158	.type = POWER_SUPPLY_TYPE_MAINS,
	159	.properties = sbs_properties,
	160	.num_properties = ARRAY_SIZE(sbs_properties),
	161	.get_property = sbs_get_property,
	162	};
	163
	164	static int sbs_probe(struct i2c_client *client,
	165	const struct i2c_device_id *id)
	166	{
	167	struct power_supply_config psy_cfg = {};
	168	struct sbs_info *chip;
	169	int ret, val;
	170
	171	chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL);
	172	if (!chip)
	173	return -ENOMEM;
	174
	175	chip->client = client;
	176	psy_cfg.of_node = client->dev.of_node;
	177	psy_cfg.drv_data = chip;
	178
	179	i2c_set_clientdata(client, chip);
	180
	181	chip->regmap = devm_regmap_init_i2c(client, &sbs_regmap);
	182	if (IS_ERR(chip->regmap))
	183	return PTR_ERR(chip->regmap);
	184
	185	/*
	186	* Before we register, we need to make sure we can actually talk
	187	* to the battery.
	188	*/
	189	ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &val);
e319f4e2 SR	190	if (ret)
e319f4e2 SR	191	return dev_err_probe(&client->dev, ret, "Failed to get device status\n");
feb583e3 NSJ	192	chip->last_state = val;
feb583e3 NSJ	193
e319f4e2 SR	194	chip->power_supply = devm_power_supply_register(&client->dev, &sbs_desc, &psy_cfg);
	195	if (IS_ERR(chip->power_supply))
	196	return dev_err_probe(&client->dev, PTR_ERR(chip->power_supply),
	197	"Failed to register power supply\n");
feb583e3 NSJ	198
	199	/*
	200	* The sbs-charger spec doesn't impose the use of an interrupt. So in
	201	* the case it wasn't provided we use polling in order get the charger's
	202	* status.
	203	*/
	204	if (client->irq) {
	205	ret = devm_request_threaded_irq(&client->dev, client->irq,
	206	NULL, sbs_irq_thread,
	207	IRQF_TRIGGER_FALLING \| IRQF_ONESHOT,
	208	dev_name(&client->dev), chip);
e319f4e2 SR	209	if (ret)
e319f4e2 SR	210	return dev_err_probe(&client->dev, ret, "Failed to request irq\n");
feb583e3 NSJ	211	} else {
	212	INIT_DELAYED_WORK(&chip->work, sbs_delayed_work);
	213	schedule_delayed_work(&chip->work,
	214	msecs_to_jiffies(SBS_CHARGER_POLL_TIME));
	215	}
	216
	217	dev_info(&client->dev,
	218	"%s: smart charger device registered\n", client->name);
	219
	220	return 0;
	221	}
	222
	223	static int sbs_remove(struct i2c_client *client)
	224	{
	225	struct sbs_info *chip = i2c_get_clientdata(client);
	226
	227	cancel_delayed_work_sync(&chip->work);
	228
	229	return 0;
	230	}
	231
	232	#ifdef CONFIG_OF
	233	static const struct of_device_id sbs_dt_ids[] = {
	234	{ .compatible = "sbs,sbs-charger" },
	235	{ },
	236	};
	237	MODULE_DEVICE_TABLE(of, sbs_dt_ids);
	238	#endif
	239
	240	static const struct i2c_device_id sbs_id[] = {
	241	{ "sbs-charger", 0 },
	242	{ }
	243	};
	244	MODULE_DEVICE_TABLE(i2c, sbs_id);
	245
	246	static struct i2c_driver sbs_driver = {
	247	.probe = sbs_probe,
	248	.remove = sbs_remove,
	249	.id_table = sbs_id,
	250	.driver = {
	251	.name = "sbs-charger",
	252	.of_match_table = of_match_ptr(sbs_dt_ids),
	253	},
	254	};
	255	module_i2c_driver(sbs_driver);
	256
	257	MODULE_AUTHOR("Nicolas Saenz Julienne <nicolassaenzj@gmail.com>");
	258	MODULE_DESCRIPTION("SBS smart charger driver");
	259	MODULE_LICENSE("GPL v2");