Commit 2219a935 authored by Laurentiu Palcu's avatar Laurentiu Palcu Committed by Sebastian Reichel
Browse files

power_supply: Add TI BQ24257 charger driver 

Based on the datasheet found here:
http://www.ti.com/lit/ds/symlink/bq24257.pdf



Signed-off-by: default avatarLaurentiu Palcu <laurentiu.palcu@intel.com>
Reviewed-by: default avatarKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: default avatarSebastian Reichel <sre@kernel.org>
parent 7f1a57fd

Documentation/devicetree/bindings/power/bq24257.txt

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Binding for TI bq24257 Li-Ion Charger



Required properties:

- compatible: Should contain one of the following:

 * "ti,bq24257"

- reg:			   integer, i2c address of the device.

- ti,battery-regulation-voltage: integer, maximum charging voltage in uV.

- ti,charge-current:	   integer, maximum charging current in uA.

- ti,termination-current:  integer, charge will be terminated when current in

			   constant-voltage phase drops below this value (in uA).



Example:



bq24257 {

	compatible = "ti,bq24257";

	reg = <0x6a>;



	ti,battery-regulation-voltage = <4200000>;

	ti,charge-current = <1000000>;

	ti,termination-current = <50000>;

};

drivers/power/Kconfig

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@@ -388,6 +388,13 @@ config CHARGER_BQ24190 
	help

	help

	  Say Y to enable support for the TI BQ24190 battery charger.

	  Say Y to enable support for the TI BQ24190 battery charger.





config CHARGER_BQ24257

	tristate "TI BQ24257 battery charger driver"

	depends on I2C && GPIOLIB

	depends on REGMAP_I2C

	help

	  Say Y to enable support for the TI BQ24257 battery charger.



config CHARGER_BQ24735

config CHARGER_BQ24735

	tristate "TI BQ24735 battery charger support"

	tristate "TI BQ24735 battery charger support"

	depends on I2C && GPIOLIB

	depends on I2C && GPIOLIB

drivers/power/Makefile

+1 −0
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@@ -58,6 +58,7 @@ obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o 
obj-$(CONFIG_CHARGER_MAX8998)	+= max8998_charger.o

obj-$(CONFIG_CHARGER_MAX8998)	+= max8998_charger.o

obj-$(CONFIG_CHARGER_BQ2415X)	+= bq2415x_charger.o

obj-$(CONFIG_CHARGER_BQ2415X)	+= bq2415x_charger.o

obj-$(CONFIG_CHARGER_BQ24190)	+= bq24190_charger.o

obj-$(CONFIG_CHARGER_BQ24190)	+= bq24190_charger.o

obj-$(CONFIG_CHARGER_BQ24257)	+= bq24257_charger.o

obj-$(CONFIG_CHARGER_BQ24735)	+= bq24735-charger.o

obj-$(CONFIG_CHARGER_BQ24735)	+= bq24735-charger.o

obj-$(CONFIG_POWER_AVS)		+= avs/

obj-$(CONFIG_POWER_AVS)		+= avs/

obj-$(CONFIG_CHARGER_SMB347)	+= smb347-charger.o

obj-$(CONFIG_CHARGER_SMB347)	+= smb347-charger.o

drivers/power/bq24257_charger.c

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/*

 * TI BQ24257 charger driver

 *

 * Copyright (C) 2015 Intel Corporation

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 */



#include <linux/module.h>

#include <linux/i2c.h>

#include <linux/power_supply.h>

#include <linux/regmap.h>

#include <linux/types.h>

#include <linux/gpio/consumer.h>

#include <linux/interrupt.h>

#include <linux/delay.h>



#include <linux/acpi.h>

#include <linux/of.h>



#define BQ24257_REG_1			0x00

#define BQ24257_REG_2			0x01

#define BQ24257_REG_3			0x02

#define BQ24257_REG_4			0x03

#define BQ24257_REG_5			0x04

#define BQ24257_REG_6			0x05

#define BQ24257_REG_7			0x06



#define BQ24257_MANUFACTURER		"Texas Instruments"

#define BQ24257_STAT_IRQ		"stat"

#define BQ24257_PG_GPIO			"pg"



#define BQ24257_ILIM_SET_DELAY		1000	/* msec */



enum bq24257_fields {

	F_WD_FAULT, F_WD_EN, F_STAT, F_FAULT,			    /* REG 1 */

	F_RESET, F_IILIMIT, F_EN_STAT, F_EN_TERM, F_CE, F_HZ_MODE,  /* REG 2 */

	F_VBAT, F_USB_DET,					    /* REG 3 */

	F_ICHG, F_ITERM,					    /* REG 4 */

	F_LOOP_STATUS, F_LOW_CHG, F_DPDM_EN, F_CE_STATUS, F_VINDPM, /* REG 5 */

	F_X2_TMR_EN, F_TMR, F_SYSOFF, F_TS_STAT,		    /* REG 6 */

	F_VOVP, F_CLR_VDP, F_FORCE_BATDET, F_FORCE_PTM,		    /* REG 7 */



	F_MAX_FIELDS

};



/* initial field values, converted from uV/uA */

struct bq24257_init_data {

	u8 ichg;	/* charge current      */

	u8 vbat;	/* regulation voltage  */

	u8 iterm;	/* termination current */

};



struct bq24257_state {

	u8 status;

	u8 fault;

	bool power_good;

};



struct bq24257_device {

	struct i2c_client *client;

	struct device *dev;

	struct power_supply *charger;



	struct regmap *rmap;

	struct regmap_field *rmap_fields[F_MAX_FIELDS];



	struct gpio_desc *pg;



	struct delayed_work iilimit_setup_work;



	struct bq24257_init_data init_data;

	struct bq24257_state state;



	struct mutex lock; /* protect state data */

};



static bool bq24257_is_volatile_reg(struct device *dev, unsigned int reg)

{

	switch (reg) {

	case BQ24257_REG_2:

	case BQ24257_REG_4:

		return false;



	default:

		return true;

	}

}



static const struct regmap_config bq24257_regmap_config = {

	.reg_bits = 8,

	.val_bits = 8,



	.max_register = BQ24257_REG_7,

	.cache_type = REGCACHE_RBTREE,



	.volatile_reg = bq24257_is_volatile_reg,

};



static const struct reg_field bq24257_reg_fields[] = {

	/* REG 1 */

	[F_WD_FAULT]		= REG_FIELD(BQ24257_REG_1, 7, 7),

	[F_WD_EN]		= REG_FIELD(BQ24257_REG_1, 6, 6),

	[F_STAT]		= REG_FIELD(BQ24257_REG_1, 4, 5),

	[F_FAULT]		= REG_FIELD(BQ24257_REG_1, 0, 3),

	/* REG 2 */

	[F_RESET]		= REG_FIELD(BQ24257_REG_2, 7, 7),

	[F_IILIMIT]		= REG_FIELD(BQ24257_REG_2, 4, 6),

	[F_EN_STAT]		= REG_FIELD(BQ24257_REG_2, 3, 3),

	[F_EN_TERM]		= REG_FIELD(BQ24257_REG_2, 2, 2),

	[F_CE]			= REG_FIELD(BQ24257_REG_2, 1, 1),

	[F_HZ_MODE]		= REG_FIELD(BQ24257_REG_2, 0, 0),

	/* REG 3 */

	[F_VBAT]		= REG_FIELD(BQ24257_REG_3, 2, 7),

	[F_USB_DET]		= REG_FIELD(BQ24257_REG_3, 0, 1),

	/* REG 4 */

	[F_ICHG]		= REG_FIELD(BQ24257_REG_4, 3, 7),

	[F_ITERM]		= REG_FIELD(BQ24257_REG_4, 0, 2),

	/* REG 5 */

	[F_LOOP_STATUS]		= REG_FIELD(BQ24257_REG_5, 6, 7),

	[F_LOW_CHG]		= REG_FIELD(BQ24257_REG_5, 5, 5),

	[F_DPDM_EN]		= REG_FIELD(BQ24257_REG_5, 4, 4),

	[F_CE_STATUS]		= REG_FIELD(BQ24257_REG_5, 3, 3),

	[F_VINDPM]		= REG_FIELD(BQ24257_REG_5, 0, 2),

	/* REG 6 */

	[F_X2_TMR_EN]		= REG_FIELD(BQ24257_REG_6, 7, 7),

	[F_TMR]			= REG_FIELD(BQ24257_REG_6, 5, 6),

	[F_SYSOFF]		= REG_FIELD(BQ24257_REG_6, 4, 4),

	[F_TS_STAT]		= REG_FIELD(BQ24257_REG_6, 0, 2),

	/* REG 7 */

	[F_VOVP]		= REG_FIELD(BQ24257_REG_7, 5, 7),

	[F_CLR_VDP]		= REG_FIELD(BQ24257_REG_7, 4, 4),

	[F_FORCE_BATDET]	= REG_FIELD(BQ24257_REG_7, 3, 3),

	[F_FORCE_PTM]		= REG_FIELD(BQ24257_REG_7, 2, 2)

};



static const u32 bq24257_vbat_map[] = {

	3500000, 3520000, 3540000, 3560000, 3580000, 3600000, 3620000, 3640000,

	3660000, 3680000, 3700000, 3720000, 3740000, 3760000, 3780000, 3800000,

	3820000, 3840000, 3860000, 3880000, 3900000, 3920000, 3940000, 3960000,

	3980000, 4000000, 4020000, 4040000, 4060000, 4080000, 4100000, 4120000,

	4140000, 4160000, 4180000, 4200000, 4220000, 4240000, 4260000, 4280000,

	4300000, 4320000, 4340000, 4360000, 4380000, 4400000, 4420000, 4440000

};



#define BQ24257_VBAT_MAP_SIZE		ARRAY_SIZE(bq24257_vbat_map)



static const u32 bq24257_ichg_map[] = {

	500000, 550000, 600000, 650000, 700000, 750000, 800000, 850000, 900000,

	950000, 1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000,

	1350000, 1400000, 1450000, 1500000, 1550000, 1600000, 1650000, 1700000,

	1750000, 1800000, 1850000, 1900000, 1950000, 2000000

};



#define BQ24257_ICHG_MAP_SIZE		ARRAY_SIZE(bq24257_ichg_map)



static const u32 bq24257_iterm_map[] = {

	50000, 75000, 100000, 125000, 150000, 175000, 200000, 225000

};



#define BQ24257_ITERM_MAP_SIZE		ARRAY_SIZE(bq24257_iterm_map)



static int bq24257_field_read(struct bq24257_device *bq,

			      enum bq24257_fields field_id)

{

	int ret;

	int val;



	ret = regmap_field_read(bq->rmap_fields[field_id], &val);

	if (ret < 0)

		return ret;



	return val;

}



static int bq24257_field_write(struct bq24257_device *bq,

			       enum bq24257_fields field_id, u8 val)

{

	return regmap_field_write(bq->rmap_fields[field_id], val);

}



static u8 bq24257_find_idx(u32 value, const u32 *map, u8 map_size)

{

	u8 idx;



	for (idx = 1; idx < map_size; idx++)

		if (value < map[idx])

			break;



	return idx - 1;

}



enum bq24257_status {

	STATUS_READY,

	STATUS_CHARGE_IN_PROGRESS,

	STATUS_CHARGE_DONE,

	STATUS_FAULT,

};



enum bq24257_fault {

	FAULT_NORMAL,

	FAULT_INPUT_OVP,

	FAULT_INPUT_UVLO,

	FAULT_SLEEP,

	FAULT_BAT_TS,

	FAULT_BAT_OVP,

	FAULT_TS,

	FAULT_TIMER,

	FAULT_NO_BAT,

	FAULT_ISET,

	FAULT_INPUT_LDO_LOW,

};



static int bq24257_power_supply_get_property(struct power_supply *psy,

					     enum power_supply_property psp,

					     union power_supply_propval *val)

{

	struct bq24257_device *bq = power_supply_get_drvdata(psy);

	struct bq24257_state state;



	mutex_lock(&bq->lock);

	state = bq->state;

	mutex_unlock(&bq->lock);



	switch (psp) {

	case POWER_SUPPLY_PROP_STATUS:

		if (!state.power_good)

			val->intval = POWER_SUPPLY_STATUS_DISCHARGING;

		else if (state.status == STATUS_READY)

			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;

		else if (state.status == STATUS_CHARGE_IN_PROGRESS)

			val->intval = POWER_SUPPLY_STATUS_CHARGING;

		else if (state.status == STATUS_CHARGE_DONE)

			val->intval = POWER_SUPPLY_STATUS_FULL;

		else

			val->intval = POWER_SUPPLY_STATUS_UNKNOWN;

		break;



	case POWER_SUPPLY_PROP_MANUFACTURER:

		val->strval = BQ24257_MANUFACTURER;

		break;



	case POWER_SUPPLY_PROP_ONLINE:

		val->intval = state.power_good;

		break;



	case POWER_SUPPLY_PROP_HEALTH:

		switch (state.fault) {

		case FAULT_NORMAL:

			val->intval = POWER_SUPPLY_HEALTH_GOOD;

			break;



		case FAULT_INPUT_OVP:

		case FAULT_BAT_OVP:

			val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;

			break;



		case FAULT_TS:

		case FAULT_BAT_TS:

			val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;

			break;



		case FAULT_TIMER:

			val->intval = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;

			break;



		default:

			val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE;

			break;

		}



		break;



	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:

		val->intval = bq24257_ichg_map[bq->init_data.ichg];

		break;



	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:

		val->intval = bq24257_ichg_map[BQ24257_ICHG_MAP_SIZE - 1];

		break;



	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:

		val->intval = bq24257_vbat_map[bq->init_data.vbat];

		break;



	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:

		val->intval = bq24257_vbat_map[BQ24257_VBAT_MAP_SIZE - 1];

		break;



	case POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT:

		val->intval = bq24257_iterm_map[bq->init_data.iterm];

		break;



	default:

		return -EINVAL;

	}



	return 0;

}



static int bq24257_get_chip_state(struct bq24257_device *bq,

				  struct bq24257_state *state)

{

	int ret;



	ret = bq24257_field_read(bq, F_STAT);

	if (ret < 0)

		return ret;



	state->status = ret;



	ret = bq24257_field_read(bq, F_FAULT);

	if (ret < 0)

		return ret;



	state->fault = ret;



	state->power_good = !gpiod_get_value_cansleep(bq->pg);



	return 0;

}



static bool bq24257_state_changed(struct bq24257_device *bq,

				  struct bq24257_state *new_state)

{

	int ret;



	mutex_lock(&bq->lock);

	ret = (bq->state.status != new_state->status ||

	       bq->state.fault != new_state->fault ||

	       bq->state.power_good != new_state->power_good);

	mutex_unlock(&bq->lock);



	return ret;

}



enum bq24257_loop_status {

	LOOP_STATUS_NONE,

	LOOP_STATUS_IN_DPM,

	LOOP_STATUS_IN_CURRENT_LIMIT,

	LOOP_STATUS_THERMAL,

};



enum bq24257_in_ilimit {

	IILIMIT_100,

	IILIMIT_150,

	IILIMIT_500,

	IILIMIT_900,

	IILIMIT_1500,

	IILIMIT_2000,

	IILIMIT_EXT,

	IILIMIT_NONE,

};



enum bq24257_port_type {

	PORT_TYPE_DCP,		/* Dedicated Charging Port */

	PORT_TYPE_CDP,		/* Charging Downstream Port */

	PORT_TYPE_SDP,		/* Standard Downstream Port */

	PORT_TYPE_NON_STANDARD,

};



enum bq24257_safety_timer {

	SAFETY_TIMER_45,

	SAFETY_TIMER_360,

	SAFETY_TIMER_540,

	SAFETY_TIMER_NONE,

};



static int bq24257_iilimit_autoset(struct bq24257_device *bq)

{

	int loop_status;

	int iilimit;

	int port_type;

	int ret;

	const u8 new_iilimit[] = {

		[PORT_TYPE_DCP] = IILIMIT_2000,

		[PORT_TYPE_CDP] = IILIMIT_2000,

		[PORT_TYPE_SDP] = IILIMIT_500,

		[PORT_TYPE_NON_STANDARD] = IILIMIT_500

	};



	ret = bq24257_field_read(bq, F_LOOP_STATUS);

	if (ret < 0)

		goto error;



	loop_status = ret;



	ret = bq24257_field_read(bq, F_IILIMIT);

	if (ret < 0)

		goto error;



	iilimit = ret;



	/*

	 * All USB ports should be able to handle 500mA. If not, DPM will lower

	 * the charging current to accommodate the power source. No need to set

	 * a lower IILIMIT value.

	 */

	if (loop_status == LOOP_STATUS_IN_DPM && iilimit == IILIMIT_500)

		return 0;



	ret = bq24257_field_read(bq, F_USB_DET);

	if (ret < 0)

		goto error;



	port_type = ret;



	ret = bq24257_field_write(bq, F_IILIMIT, new_iilimit[port_type]);

	if (ret < 0)

		goto error;



	ret = bq24257_field_write(bq, F_TMR, SAFETY_TIMER_360);

	if (ret < 0)

		goto error;



	ret = bq24257_field_write(bq, F_CLR_VDP, 1);

	if (ret < 0)

		goto error;



	dev_dbg(bq->dev, "port/loop = %d/%d -> iilimit = %d\n",

		port_type, loop_status, new_iilimit[port_type]);



	return 0;



error:

	dev_err(bq->dev, "%s: Error communicating with the chip.\n", __func__);

	return ret;

}



static void bq24257_iilimit_setup_work(struct work_struct *work)

{

	struct bq24257_device *bq = container_of(work, struct bq24257_device,

						 iilimit_setup_work.work);



	bq24257_iilimit_autoset(bq);

}



static void bq24257_handle_state_change(struct bq24257_device *bq,

					struct bq24257_state *new_state)

{

	int ret;

	struct bq24257_state old_state;

	bool reset_iilimit = false;

	bool config_iilimit = false;



	mutex_lock(&bq->lock);

	old_state = bq->state;

	mutex_unlock(&bq->lock);



	if (!new_state->power_good) {			     /* power removed */

		cancel_delayed_work_sync(&bq->iilimit_setup_work);



		/* activate D+/D- port detection algorithm */

		ret = bq24257_field_write(bq, F_DPDM_EN, 1);

		if (ret < 0)

			goto error;



		reset_iilimit = true;

	} else if (!old_state.power_good) {		    /* power inserted */

		config_iilimit = true;

	} else if (new_state->fault == FAULT_NO_BAT) {	   /* battery removed */

		cancel_delayed_work_sync(&bq->iilimit_setup_work);



		reset_iilimit = true;

	} else if (old_state.fault == FAULT_NO_BAT) {    /* battery connected */

		config_iilimit = true;

	} else if (new_state->fault == FAULT_TIMER) { /* safety timer expired */

		dev_err(bq->dev, "Safety timer expired! Battery dead?\n");

	}



	if (reset_iilimit) {

		ret = bq24257_field_write(bq, F_IILIMIT, IILIMIT_500);

		if (ret < 0)

			goto error;

	} else if (config_iilimit) {

		schedule_delayed_work(&bq->iilimit_setup_work,

				      msecs_to_jiffies(BQ24257_ILIM_SET_DELAY));

	}



	return;



error:

	dev_err(bq->dev, "%s: Error communicating with the chip.\n", __func__);

}



static irqreturn_t bq24257_irq_handler_thread(int irq, void *private)

{

	int ret;

	struct bq24257_device *bq = private;

	struct bq24257_state state;



	ret = bq24257_get_chip_state(bq, &state);

	if (ret < 0)

		return IRQ_HANDLED;



	if (!bq24257_state_changed(bq, &state))

		return IRQ_HANDLED;



	dev_dbg(bq->dev, "irq(state changed): status/fault/pg = %d/%d/%d\n",

		state.status, state.fault, state.power_good);



	bq24257_handle_state_change(bq, &state);



	mutex_lock(&bq->lock);

	bq->state = state;

	mutex_unlock(&bq->lock);



	power_supply_changed(bq->charger);



	return IRQ_HANDLED;

}



static int bq24257_hw_init(struct bq24257_device *bq)

{

	int ret;

	int i;

	struct bq24257_state state;



	const struct {

		int field;

		u32 value;

	} init_data[] = {

		{F_ICHG, bq->init_data.ichg},

		{F_VBAT, bq->init_data.vbat},

		{F_ITERM, bq->init_data.iterm}

	};



	/*

	 * Disable the watchdog timer to prevent the IC from going back to

	 * default settings after 50 seconds of I2C inactivity.

	 */

	ret = bq24257_field_write(bq, F_WD_EN, 0);

	if (ret < 0)

		return ret;



	/* configure the charge currents and voltages */

	for (i = 0; i < ARRAY_SIZE(init_data); i++) {

		ret = bq24257_field_write(bq, init_data[i].field,

					  init_data[i].value);

		if (ret < 0)

			return ret;

	}



	ret = bq24257_get_chip_state(bq, &state);

	if (ret < 0)

		return ret;



	mutex_lock(&bq->lock);

	bq->state = state;

	mutex_unlock(&bq->lock);



	if (!state.power_good)

		/* activate D+/D- detection algorithm */

		ret = bq24257_field_write(bq, F_DPDM_EN, 1);

	else if (state.fault != FAULT_NO_BAT)

		ret = bq24257_iilimit_autoset(bq);



	return ret;

}



static enum power_supply_property bq24257_power_supply_props[] = {

	POWER_SUPPLY_PROP_MANUFACTURER,

	POWER_SUPPLY_PROP_STATUS,

	POWER_SUPPLY_PROP_ONLINE,

	POWER_SUPPLY_PROP_HEALTH,

	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,

	POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX,

	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,

	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX,

	POWER_SUPPLY_PROP_CHARGE_TERM_CURRENT,

};



static char *bq24257_charger_supplied_to[] = {

	"main-battery",

};



static const struct power_supply_desc bq24257_power_supply_desc = {

	.name = "bq24257-charger",

	.type = POWER_SUPPLY_TYPE_USB,

	.properties = bq24257_power_supply_props,

	.num_properties = ARRAY_SIZE(bq24257_power_supply_props),

	.get_property = bq24257_power_supply_get_property,

};



static int bq24257_power_supply_init(struct bq24257_device *bq)

{

	struct power_supply_config psy_cfg = { .drv_data = bq, };



	psy_cfg.supplied_to = bq24257_charger_supplied_to;

	psy_cfg.num_supplicants = ARRAY_SIZE(bq24257_charger_supplied_to);



	bq->charger = power_supply_register(bq->dev, &bq24257_power_supply_desc,

					    &psy_cfg);

	if (IS_ERR(bq->charger))

		return PTR_ERR(bq->charger);



	return 0;

}



static int bq24257_irq_probe(struct bq24257_device *bq)

{

	int ret;

	struct gpio_desc *stat_irq;



	stat_irq = devm_gpiod_get_index(bq->dev, BQ24257_STAT_IRQ, 0);

	if (IS_ERR(stat_irq)) {

		dev_err(bq->dev, "could not probe stat_irq pin\n");

		return PTR_ERR(stat_irq);

	}



	ret = gpiod_direction_input(stat_irq);

	if (ret < 0)

		return ret;



	return gpiod_to_irq(stat_irq);

}



static int bq24257_pg_gpio_probe(struct bq24257_device *bq)

{

	bq->pg = devm_gpiod_get_index(bq->dev, BQ24257_PG_GPIO, 0);

	if (IS_ERR(bq->pg)) {

		dev_err(bq->dev, "could not probe PG pin\n");

		return PTR_ERR(bq->pg);

	}



	return gpiod_direction_input(bq->pg);

}



static int bq24257_fw_probe(struct bq24257_device *bq)

{

	int ret;

	u32 property;



	ret = device_property_read_u32(bq->dev, "ti,charge-current", &property);

	if (ret < 0)

		return ret;



	bq->init_data.ichg = bq24257_find_idx(property, bq24257_ichg_map,

					      BQ24257_ICHG_MAP_SIZE);



	ret = device_property_read_u32(bq->dev, "ti,battery-regulation-voltage",

				       &property);

	if (ret < 0)

		return ret;



	bq->init_data.vbat = bq24257_find_idx(property, bq24257_vbat_map,

					      BQ24257_VBAT_MAP_SIZE);



	ret = device_property_read_u32(bq->dev, "ti,termination-current",

				       &property);

	if (ret < 0)

		return ret;



	bq->init_data.iterm = bq24257_find_idx(property, bq24257_iterm_map,

					       BQ24257_ITERM_MAP_SIZE);



	return 0;

}



static int bq24257_probe(struct i2c_client *client,

			 const struct i2c_device_id *id)

{

	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);

	struct device *dev = &client->dev;

	struct bq24257_device *bq;

	int ret;

	int i;



	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {

		dev_err(dev, "No support for SMBUS_BYTE_DATA\n");

		return -ENODEV;

	}



	bq = devm_kzalloc(dev, sizeof(*bq), GFP_KERNEL);

	if (!bq)

		return -ENOMEM;



	bq->client = client;

	bq->dev = dev;



	mutex_init(&bq->lock);



	bq->rmap = devm_regmap_init_i2c(client, &bq24257_regmap_config);

	if (IS_ERR(bq->rmap)) {

		dev_err(dev, "failed to allocate register map\n");

		return PTR_ERR(bq->rmap);

	}



	for (i = 0; i < ARRAY_SIZE(bq24257_reg_fields); i++) {

		const struct reg_field *reg_fields = bq24257_reg_fields;



		bq->rmap_fields[i] = devm_regmap_field_alloc(dev, bq->rmap,

							     reg_fields[i]);

		if (IS_ERR(bq->rmap_fields[i])) {

			dev_err(dev, "cannot allocate regmap field\n");

			return PTR_ERR(bq->rmap_fields[i]);

		}

	}



	i2c_set_clientdata(client, bq);



	INIT_DELAYED_WORK(&bq->iilimit_setup_work, bq24257_iilimit_setup_work);



	if (!dev->platform_data) {

		ret = bq24257_fw_probe(bq);

		if (ret < 0) {

			dev_err(dev, "Cannot read device properties.\n");

			return ret;

		}

	} else {

		return -ENODEV;

	}



	/* we can only check Power Good status by probing the PG pin */

	ret = bq24257_pg_gpio_probe(bq);

	if (ret < 0)

		return ret;



	/* reset all registers to defaults */

	ret = bq24257_field_write(bq, F_RESET, 1);

	if (ret < 0)

		return ret;



	/*

	 * Put the RESET bit back to 0, in cache. For some reason the HW always

	 * returns 1 on this bit, so this is the only way to avoid resetting the

	 * chip every time we update another field in this register.

	 */

	ret = bq24257_field_write(bq, F_RESET, 0);

	if (ret < 0)

		return ret;



	ret = bq24257_hw_init(bq);

	if (ret < 0) {

		dev_err(dev, "Cannot initialize the chip.\n");

		return ret;

	}



	if (client->irq <= 0)

		client->irq = bq24257_irq_probe(bq);



	if (client->irq < 0) {

		dev_err(dev, "no irq resource found\n");

		return client->irq;

	}



	ret = devm_request_threaded_irq(dev, client->irq, NULL,

					bq24257_irq_handler_thread,

					IRQF_TRIGGER_FALLING |

					IRQF_TRIGGER_RISING | IRQF_ONESHOT,

					BQ24257_STAT_IRQ, bq);

	if (ret)

		return ret;



	ret = bq24257_power_supply_init(bq);

	if (ret < 0)

		dev_err(dev, "Failed to register power supply\n");



	return ret;

}



static int bq24257_remove(struct i2c_client *client)

{

	struct bq24257_device *bq = i2c_get_clientdata(client);



	cancel_delayed_work_sync(&bq->iilimit_setup_work);



	power_supply_unregister(bq->charger);



	bq24257_field_write(bq, F_RESET, 1); /* reset to defaults */



	return 0;

}



#ifdef CONFIG_PM_SLEEP

static int bq24257_suspend(struct device *dev)

{

	struct bq24257_device *bq = dev_get_drvdata(dev);

	int ret = 0;



	cancel_delayed_work_sync(&bq->iilimit_setup_work);



	/* reset all registers to default (and activate standalone mode) */

	ret = bq24257_field_write(bq, F_RESET, 1);

	if (ret < 0)

		dev_err(bq->dev, "Cannot reset chip to standalone mode.\n");



	return ret;

}



static int bq24257_resume(struct device *dev)

{

	int ret;

	struct bq24257_device *bq = dev_get_drvdata(dev);



	ret = regcache_drop_region(bq->rmap, BQ24257_REG_1, BQ24257_REG_7);

	if (ret < 0)

		return ret;



	ret = bq24257_field_write(bq, F_RESET, 0);

	if (ret < 0)

		return ret;



	ret = bq24257_hw_init(bq);

	if (ret < 0) {

		dev_err(bq->dev, "Cannot init chip after resume.\n");

		return ret;

	}



	/* signal userspace, maybe state changed while suspended */

	power_supply_changed(bq->charger);



	return 0;

}

#endif



static const struct dev_pm_ops bq24257_pm = {

	SET_SYSTEM_SLEEP_PM_OPS(bq24257_suspend, bq24257_resume)

};



static const struct i2c_device_id bq24257_i2c_ids[] = {

	{ "bq24257", 0 },

	{},

};

MODULE_DEVICE_TABLE(i2c, bq24257_i2c_ids);



static const struct of_device_id bq24257_of_match[] = {

	{ .compatible = "ti,bq24257", },

	{ },

};

MODULE_DEVICE_TABLE(of, bq24257_of_match);



static const struct acpi_device_id bq24257_acpi_match[] = {

	{"BQ242570", 0},

	{},

};

MODULE_DEVICE_TABLE(acpi, bq24257_acpi_match);



static struct i2c_driver bq24257_driver = {

	.driver = {

		.name = "bq24257-charger",

		.of_match_table = of_match_ptr(bq24257_of_match),

		.acpi_match_table = ACPI_PTR(bq24257_acpi_match),

		.pm = &bq24257_pm,

	},

	.probe = bq24257_probe,

	.remove = bq24257_remove,

	.id_table = bq24257_i2c_ids,

};

module_i2c_driver(bq24257_driver);



MODULE_AUTHOR("Laurentiu Palcu <laurentiu.palcu@intel.com>");

MODULE_DESCRIPTION("bq24257 charger driver");

MODULE_LICENSE("GPL");