Re: [RFC PATCH] power: axp288_charger: axp288 charger driver

[Lee Jones <lee.jones@linaro.org>]

On Fri, 24 Apr 2015, Ramakrishna Pallala wrote:

> This patch adds new power supply charger driver support
> for X-Power AXP288 PMIC integrated charger.
> 
> This driver interfaces with the axp20x mfd driver as a cell
> and listens to extcon cable events for setting up charging.
> 
> Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
> ---
>  drivers/power/Kconfig          |    7 +
>  drivers/power/Makefile         |    1 +
>  drivers/power/axp288_charger.c |  936 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/axp20x.h     |    7 +

For the MFD changes:
  Acked-by: Lee Jones <lee.jones@linaro.org>

>  4 files changed, 951 insertions(+)
>  create mode 100644 drivers/power/axp288_charger.c
> 
> diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
> index 4091fb0..c7d7e8b 100644
> --- a/drivers/power/Kconfig
> +++ b/drivers/power/Kconfig
> @@ -204,6 +204,13 @@ config CHARGER_DA9150
>  	  This driver can also be built as a module. If so, the module will be
>  	  called da9150-charger.
>  
> +config AXP288_CHARGER
> +	tristate "X-Powers AXP288 Charger"
> +	depends on MFD_AXP20X && EXTCON_AXP288
> +	help
> +	  Say yes here to have support X-Power AXP288 power management IC (PMIC)
> +	  integrated charger.
> +
>  config AXP288_FUEL_GAUGE
>  	tristate "X-Powers AXP288 Fuel Gauge"
>  	depends on MFD_AXP20X && IIO
> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
> index b7b0181..5acae5f 100644
> --- a/drivers/power/Makefile
> +++ b/drivers/power/Makefile
> @@ -64,3 +64,4 @@ obj-$(CONFIG_CHARGER_SMB347)	+= smb347-charger.o
>  obj-$(CONFIG_CHARGER_TPS65090)	+= tps65090-charger.o
>  obj-$(CONFIG_POWER_RESET)	+= reset/
>  obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
> +obj-$(CONFIG_AXP288_CHARGER)	+= axp288_charger.o
> diff --git a/drivers/power/axp288_charger.c b/drivers/power/axp288_charger.c
> new file mode 100644
> index 0000000..0106045
> --- /dev/null
> +++ b/drivers/power/axp288_charger.c
> @@ -0,0 +1,936 @@
> +/*
> + * axp288_charger.c - Xpower AXP288 PMIC Charger driver
> + *
> + * Copyright (C) 2014 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; version 2 of the License.
> + *
> + * 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/device.h>
> +#include <linux/regmap.h>
> +#include <linux/workqueue.h>
> +#include <linux/delay.h>
> +#include <linux/platform_device.h>
> +#include <linux/usb/otg.h>
> +#include <linux/notifier.h>
> +#include <linux/power_supply.h>
> +#include <linux/notifier.h>
> +#include <linux/property.h>
> +#include <linux/mfd/axp20x.h>
> +#include <linux/extcon.h>
> +
> +#define PS_STAT_VBUS_TRIGGER		(1 << 0)
> +#define PS_STAT_BAT_CHRG_DIR		(1 << 2)
> +#define PS_STAT_VBAT_ABOVE_VHOLD	(1 << 3)
> +#define PS_STAT_VBUS_VALID		(1 << 4)
> +#define PS_STAT_VBUS_PRESENT		(1 << 5)
> +
> +#define CHRG_STAT_BAT_SAFE_MODE		(1 << 3)
> +#define CHRG_STAT_BAT_VALID		(1 << 4)
> +#define CHRG_STAT_BAT_PRESENT		(1 << 5)
> +#define CHRG_STAT_CHARGING		(1 << 6)
> +#define CHRG_STAT_PMIC_OTP		(1 << 7)
> +
> +#define VBUS_ISPOUT_CUR_LIM_MASK	0x03
> +#define VBUS_ISPOUT_CUR_LIM_BIT_POS	0
> +#define VBUS_ISPOUT_CUR_LIM_900MA	0x0	/* 900mA */
> +#define VBUS_ISPOUT_CUR_LIM_1500MA	0x1	/* 1500mA */
> +#define VBUS_ISPOUT_CUR_LIM_2000MA	0x2	/* 2000mA */
> +#define VBUS_ISPOUT_CUR_NO_LIM		0x3	/* 2500mA */
> +#define VBUS_ISPOUT_VHOLD_SET_MASK	0x31
> +#define VBUS_ISPOUT_VHOLD_SET_BIT_POS	0x3
> +#define VBUS_ISPOUT_VHOLD_SET_OFFSET	4000	/* 4000mV */
> +#define VBUS_ISPOUT_VHOLD_SET_LSB_RES	100	/* 100mV */
> +#define VBUS_ISPOUT_VHOLD_SET_4300MV	0x3	/* 4300mV */
> +#define VBUS_ISPOUT_VBUS_PATH_DIS	(1 << 7)
> +
> +#define CHRG_CCCV_CC_MASK		0xf		/* 4 bits */
> +#define CHRG_CCCV_CC_BIT_POS		0
> +#define CHRG_CCCV_CC_OFFSET		200		/* 200mA */
> +#define CHRG_CCCV_CC_LSB_RES		200		/* 200mA */
> +#define CHRG_CCCV_ITERM_20P		(1 << 4)	/* 20% of CC */
> +#define CHRG_CCCV_CV_MASK		0x60		/* 2 bits */
> +#define CHRG_CCCV_CV_BIT_POS		5
> +#define CHRG_CCCV_CV_4100MV		0x0		/* 4.10V */
> +#define CHRG_CCCV_CV_4150MV		0x1		/* 4.15V */
> +#define CHRG_CCCV_CV_4200MV		0x2		/* 4.20V */
> +#define CHRG_CCCV_CV_4350MV		0x3		/* 4.35V */
> +#define CHRG_CCCV_CHG_EN		(1 << 7)
> +
> +#define CNTL2_CC_TIMEOUT_MASK		0x3	/* 2 bits */
> +#define CNTL2_CC_TIMEOUT_OFFSET		6	/* 6 Hrs */
> +#define CNTL2_CC_TIMEOUT_LSB_RES	2	/* 2 Hrs */
> +#define CNTL2_CC_TIMEOUT_12HRS		0x3	/* 12 Hrs */
> +#define CNTL2_CHGLED_TYPEB		(1 << 4)
> +#define CNTL2_CHG_OUT_TURNON		(1 << 5)
> +#define CNTL2_PC_TIMEOUT_MASK		0xC0
> +#define CNTL2_PC_TIMEOUT_OFFSET		40	/* 40 mins */
> +#define CNTL2_PC_TIMEOUT_LSB_RES	10	/* 10 mins */
> +#define CNTL2_PC_TIMEOUT_70MINS		0x3
> +
> +#define CHRG_ILIM_TEMP_LOOP_EN		(1 << 3)
> +#define CHRG_VBUS_ILIM_MASK		0xf0
> +#define CHRG_VBUS_ILIM_BIT_POS		4
> +#define CHRG_VBUS_ILIM_100MA		0x0	/* 100mA */
> +#define CHRG_VBUS_ILIM_500MA		0x1	/* 500mA */
> +#define CHRG_VBUS_ILIM_900MA		0x2	/* 900mA */
> +#define CHRG_VBUS_ILIM_1500MA		0x3	/* 1500mA */
> +#define CHRG_VBUS_ILIM_2000MA		0x4	/* 2000mA */
> +#define CHRG_VBUS_ILIM_2500MA		0x5	/* 2500mA */
> +#define CHRG_VBUS_ILIM_3000MA		0x6	/* 3000mA */
> +
> +#define CHRG_VLTFC_0C			0xA5	/* 0 DegC */
> +#define CHRG_VHTFC_45C			0x1F	/* 45 DegC */
> +
> +#define BAT_IRQ_CFG_CHRG_DONE		(1 << 2)
> +#define BAT_IRQ_CFG_CHRG_START		(1 << 3)
> +#define BAT_IRQ_CFG_BAT_SAFE_EXIT	(1 << 4)
> +#define BAT_IRQ_CFG_BAT_SAFE_ENTER	(1 << 5)
> +#define BAT_IRQ_CFG_BAT_DISCON		(1 << 6)
> +#define BAT_IRQ_CFG_BAT_CONN		(1 << 7)
> +#define BAT_IRQ_CFG_BAT_MASK		0xFC
> +
> +#define TEMP_IRQ_CFG_QCBTU		(1 << 4)
> +#define TEMP_IRQ_CFG_CBTU		(1 << 5)
> +#define TEMP_IRQ_CFG_QCBTO		(1 << 6)
> +#define TEMP_IRQ_CFG_CBTO		(1 << 7)
> +#define TEMP_IRQ_CFG_MASK		0xF0
> +
> +#define FG_CNTL_OCV_ADJ_EN		(1 << 3)
> +
> +#define CV_4100MV			4100	/* 4100mV */
> +#define CV_4150MV			4150	/* 4150mV */
> +#define CV_4200MV			4200	/* 4200mV */
> +#define CV_4350MV			4350	/* 4350mV */
> +
> +#define CC_200MA			200	/*  200mA */
> +#define CC_600MA			600	/*  600mA */
> +#define CC_800MA			800	/*  800mA */
> +#define CC_1000MA			1000	/* 1000mA */
> +#define CC_1600MA			1600	/* 1600mA */
> +#define CC_2000MA			2000	/* 2000mA */
> +
> +#define ILIM_100MA			100	/* 100mA */
> +#define ILIM_500MA			500	/* 500mA */
> +#define ILIM_900MA			900	/* 900mA */
> +#define ILIM_1500MA			1500	/* 1500mA */
> +#define ILIM_2000MA			2000	/* 2000mA */
> +#define ILIM_2500MA			2500	/* 2500mA */
> +#define ILIM_3000MA			3000	/* 3000mA */
> +
> +#define AXP288_EXTCON_DEV_NAME		"axp288_extcon"
> +
> +#define AXP288_EXTCON_CABLE_SDP		"Slow-charger"
> +#define AXP288_EXTCON_CABLE_CDP		"Charge-downstream"
> +#define AXP288_EXTCON_CABLE_DCP		"Fast-charger"
> +
> +enum {
> +	VBUS_OV_IRQ = 0,
> +	CHARGE_DONE_IRQ,
> +	CHARGE_CHARGING_IRQ,
> +	BAT_SAFE_QUIT_IRQ,
> +	BAT_SAFE_ENTER_IRQ,
> +	QCBTU_IRQ,
> +	CBTU_IRQ,
> +	QCBTO_IRQ,
> +	CBTO_IRQ,
> +	CHRG_INTR_END,
> +};
> +
> +struct axp288_chrg_info {
> +	struct platform_device *pdev;
> +	struct axp20x_chrg_pdata *pdata;
> +	struct regmap *regmap;
> +	struct regmap_irq_chip_data *regmap_irqc;
> +	int irq[CHRG_INTR_END];
> +	struct power_supply *psy_usb;
> +	struct mutex lock;
> +
> +	/* OTG/Host mode */
> +	struct {
> +		struct work_struct work;
> +		struct extcon_specific_cable_nb cable;
> +		struct notifier_block id_nb;
> +		bool id_short;
> +	} otg;
> +
> +	/* SDP/CDP/DCP USB charging cable notifications */
> +	struct {
> +		struct extcon_dev *edev;
> +		bool connected;
> +		enum power_supply_type chg_type;
> +		struct notifier_block nb;
> +		struct work_struct work;
> +	} cable;
> +
> +	int health;
> +	int inlmt;
> +	int cc;
> +	int cv;
> +	int max_cc;
> +	int max_cv;
> +	bool online;
> +	bool present;
> +	bool enable_charger;
> +	bool is_charger_enabled;
> +};
> +
> +static inline int axp288_charger_set_cc(struct axp288_chrg_info *info, int cc)
> +{
> +	u8 reg_val;
> +	int ret;
> +
> +	if (cc < CHRG_CCCV_CC_OFFSET)
> +		cc = CHRG_CCCV_CC_OFFSET;
> +	else if (cc > info->max_cc)
> +		cc = info->max_cc;
> +
> +	reg_val = (cc - CHRG_CCCV_CC_OFFSET) / CHRG_CCCV_CC_LSB_RES;
> +	cc = (reg_val * CHRG_CCCV_CC_LSB_RES) + CHRG_CCCV_CC_OFFSET;
> +	reg_val = reg_val << CHRG_CCCV_CC_BIT_POS;
> +
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_CHRG_CTRL1,
> +				CHRG_CCCV_CC_MASK, reg_val);
> +	if (ret >= 0)
> +		info->cc = cc;
> +
> +	return ret;
> +}
> +
> +static inline int axp288_charger_set_cv(struct axp288_chrg_info *info, int cv)
> +{
> +	u8 reg_val;
> +	int ret;
> +
> +	if (cv <= CV_4100MV) {
> +		reg_val = CHRG_CCCV_CV_4100MV;
> +		cv = CV_4100MV;
> +	} else if (cv <= CV_4150MV) {
> +		reg_val = CHRG_CCCV_CV_4150MV;
> +		cv = CV_4150MV;
> +	} else if (cv <= CV_4200MV) {
> +		reg_val = CHRG_CCCV_CV_4200MV;
> +		cv = CV_4200MV;
> +	} else {
> +		reg_val = CHRG_CCCV_CV_4350MV;
> +		cv = CV_4350MV;
> +	}
> +
> +	reg_val = reg_val << CHRG_CCCV_CV_BIT_POS;
> +
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_CHRG_CTRL1,
> +				CHRG_CCCV_CV_MASK, reg_val);
> +
> +	if (ret >= 0)
> +		info->cv = cv;
> +
> +	return ret;
> +}
> +
> +static inline int axp288_charger_set_vbus_inlmt(struct axp288_chrg_info *info,
> +					   int inlmt)
> +{
> +	int ret;
> +	unsigned int val;
> +	u8 reg_val;
> +
> +	/* Read in limit register */
> +	ret = regmap_read(info->regmap, AXP20X_CHRG_BAK_CTRL, &val);
> +	if (ret < 0)
> +		goto set_inlmt_fail;
> +
> +	if (inlmt <= ILIM_100MA) {
> +		reg_val = CHRG_VBUS_ILIM_100MA;
> +		inlmt = ILIM_100MA;
> +	} else if (inlmt <= ILIM_500MA) {
> +		reg_val = CHRG_VBUS_ILIM_500MA;
> +		inlmt = ILIM_500MA;
> +	} else if (inlmt <= ILIM_900MA) {
> +		reg_val = CHRG_VBUS_ILIM_900MA;
> +		inlmt = ILIM_900MA;
> +	} else if (inlmt <= ILIM_1500MA) {
> +		reg_val = CHRG_VBUS_ILIM_1500MA;
> +		inlmt = ILIM_1500MA;
> +	} else if (inlmt <= ILIM_2000MA) {
> +		reg_val = CHRG_VBUS_ILIM_2000MA;
> +		inlmt = ILIM_2000MA;
> +	} else if (inlmt <= ILIM_2500MA) {
> +		reg_val = CHRG_VBUS_ILIM_2500MA;
> +		inlmt = ILIM_2500MA;
> +	} else {
> +		reg_val = CHRG_VBUS_ILIM_3000MA;
> +		inlmt = ILIM_3000MA;
> +	}
> +
> +	reg_val = (val & ~CHRG_VBUS_ILIM_MASK)
> +			| (reg_val << CHRG_VBUS_ILIM_BIT_POS);
> +	ret = regmap_write(info->regmap, AXP20X_CHRG_BAK_CTRL, reg_val);
> +	if (ret >= 0)
> +		info->inlmt = inlmt;
> +	else
> +		dev_err(&info->pdev->dev, "charger BAK control %d\n", ret);
> +
> +
> +set_inlmt_fail:
> +	return ret;
> +}
> +
> +static int axp288_charger_vbus_path_select(struct axp288_chrg_info *info,
> +								bool enable)
> +{
> +	int ret;
> +
> +	if (enable)
> +		ret = regmap_update_bits(info->regmap, AXP20X_VBUS_IPSOUT_MGMT,
> +					VBUS_ISPOUT_VBUS_PATH_DIS, 0);
> +	else
> +		ret = regmap_update_bits(info->regmap, AXP20X_VBUS_IPSOUT_MGMT,
> +			VBUS_ISPOUT_VBUS_PATH_DIS, VBUS_ISPOUT_VBUS_PATH_DIS);
> +
> +	if (ret < 0)
> +		dev_err(&info->pdev->dev, "axp288 vbus path select %d\n", ret);
> +
> +
> +	return ret;
> +}
> +
> +static int axp288_charger_enable_charger(struct axp288_chrg_info *info,
> +								bool enable)
> +{
> +	int ret;
> +
> +	if (enable)
> +		ret = regmap_update_bits(info->regmap, AXP20X_CHRG_CTRL1,
> +				CHRG_CCCV_CHG_EN, CHRG_CCCV_CHG_EN);
> +	else
> +		ret = regmap_update_bits(info->regmap, AXP20X_CHRG_CTRL1,
> +				CHRG_CCCV_CHG_EN, 0);
> +	if (ret < 0)
> +		dev_err(&info->pdev->dev, "axp288 enable charger %d\n", ret);
> +	else
> +		info->is_charger_enabled = enable;
> +
> +	return ret;
> +}
> +
> +static int axp288_charger_is_present(struct axp288_chrg_info *info)
> +{
> +	int ret, present = 0;
> +	unsigned int val;
> +
> +	ret = regmap_read(info->regmap, AXP20X_PWR_INPUT_STATUS, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (val & PS_STAT_VBUS_PRESENT)
> +		present = 1;
> +	return present;
> +}
> +
> +static int axp288_charger_is_online(struct axp288_chrg_info *info)
> +{
> +	int ret, online = 0;
> +	unsigned int val;
> +
> +	ret = regmap_read(info->regmap, AXP20X_PWR_INPUT_STATUS, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (val & PS_STAT_VBUS_VALID)
> +		online = 1;
> +	return online;
> +}
> +
> +static int axp288_get_charger_health(struct axp288_chrg_info *info)
> +{
> +	int ret, pwr_stat, chrg_stat;
> +	int health = POWER_SUPPLY_HEALTH_UNKNOWN;
> +	unsigned int val;
> +
> +	ret = regmap_read(info->regmap, AXP20X_PWR_INPUT_STATUS, &val);
> +	if ((ret < 0) || !(val & PS_STAT_VBUS_PRESENT))
> +		goto health_read_fail;
> +	else
> +		pwr_stat = val;
> +
> +	ret = regmap_read(info->regmap, AXP20X_PWR_OP_MODE, &val);
> +	if (ret < 0)
> +		goto health_read_fail;
> +	else
> +		chrg_stat = val;
> +
> +	if (!(pwr_stat & PS_STAT_VBUS_VALID))
> +		health = POWER_SUPPLY_HEALTH_DEAD;
> +	else if (chrg_stat & CHRG_STAT_PMIC_OTP)
> +		health = POWER_SUPPLY_HEALTH_OVERHEAT;
> +	else if (chrg_stat & CHRG_STAT_BAT_SAFE_MODE)
> +		health = POWER_SUPPLY_HEALTH_SAFETY_TIMER_EXPIRE;
> +	else
> +		health = POWER_SUPPLY_HEALTH_GOOD;
> +
> +health_read_fail:
> +	return health;
> +}
> +
> +static int axp288_charger_usb_set_property(struct power_supply *psy,
> +				    enum power_supply_property psp,
> +				    const union power_supply_propval *val)
> +{
> +	struct axp288_chrg_info *info = power_supply_get_drvdata(psy);
> +	int ret = 0;
> +	int scaled_val;
> +
> +	mutex_lock(&info->lock);
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> +		scaled_val = min(val->intval, info->max_cc);
> +		scaled_val = DIV_ROUND_CLOSEST(scaled_val, 1000);
> +		ret = axp288_charger_set_cc(info, scaled_val);
> +		if (ret < 0)
> +			dev_warn(&info->pdev->dev, "set charge current failed\n");
> +		break;
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> +		scaled_val = min(val->intval, info->max_cv);
> +		scaled_val = DIV_ROUND_CLOSEST(scaled_val, 1000);
> +		ret = axp288_charger_set_cv(info, scaled_val);
> +		if (ret < 0)
> +			dev_warn(&info->pdev->dev, "set charge voltage failed\n");
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +	mutex_unlock(&info->lock);
> +	return ret;
> +}
> +
> +static int axp288_charger_usb_get_property(struct power_supply *psy,
> +				    enum power_supply_property psp,
> +				    union power_supply_propval *val)
> +{
> +	struct axp288_chrg_info *info = power_supply_get_drvdata(psy);
> +	int ret = 0;
> +
> +	mutex_lock(&info->lock);
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_PRESENT:
> +		/* Check for OTG case first */
> +		if (info->otg.id_short) {
> +			val->intval = 0;
> +			break;
> +		}
> +		ret = axp288_charger_is_present(info);
> +		if (ret < 0)
> +			goto psy_get_prop_fail;
> +		info->present = ret;
> +		val->intval = info->present;
> +		break;
> +	case POWER_SUPPLY_PROP_ONLINE:
> +		/* Check for OTG case first */
> +		if (info->otg.id_short) {
> +			val->intval = 0;
> +			break;
> +		}
> +		ret = axp288_charger_is_online(info);
> +		if (ret < 0)
> +			goto psy_get_prop_fail;
> +		info->online = ret;
> +		val->intval = info->online;
> +		break;
> +	case POWER_SUPPLY_PROP_HEALTH:
> +		val->intval = axp288_get_charger_health(info);
> +		break;
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> +		val->intval = info->cc * 1000;
> +		break;
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX:
> +		val->intval = info->max_cc * 1000;
> +		break;
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> +		val->intval = info->cv * 1000;
> +		break;
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE_MAX:
> +		val->intval = info->max_cv * 1000;
> +		break;
> +	case POWER_SUPPLY_PROP_CHARGE_CONTROL_LIMIT:
> +		val->intval = info->inlmt * 1000;
> +		break;
> +	default:
> +		ret = -EINVAL;
> +		goto psy_get_prop_fail;
> +	}
> +
> +psy_get_prop_fail:
> +	mutex_unlock(&info->lock);
> +	return ret;
> +}
> +
> +static int axp288_charger_property_is_writeable(struct power_supply *psy,
> +		enum power_supply_property psp)
> +{
> +	int ret;
> +
> +	switch (psp) {
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> +	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:
> +		ret = 1;
> +		break;
> +	default:
> +		ret = 0;
> +	}
> +
> +	return ret;
> +}
> +
> +static enum power_supply_property axp288_usb_props[] = {
> +	POWER_SUPPLY_PROP_PRESENT,
> +	POWER_SUPPLY_PROP_ONLINE,
> +	POWER_SUPPLY_PROP_TYPE,
> +	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_CONTROL_LIMIT,
> +};
> +
> +static const struct power_supply_desc axp288_charger_desc = {
> +	.name			= "axp288_charger",
> +	.type			= POWER_SUPPLY_TYPE_USB,
> +	.properties		= axp288_usb_props,
> +	.num_properties		= ARRAY_SIZE(axp288_usb_props),
> +	.get_property		= axp288_charger_usb_get_property,
> +	.set_property		= axp288_charger_usb_set_property,
> +	.property_is_writeable	= axp288_charger_property_is_writeable,
> +};
> +
> +static irqreturn_t axp288_charger_irq_thread_handler(int irq, void *dev)
> +{
> +	struct axp288_chrg_info *info = dev;
> +	int i;
> +
> +	for (i = 0; i < CHRG_INTR_END; i++) {
> +		if (info->irq[i] == irq)
> +			break;
> +	}
> +
> +	if (i >= CHRG_INTR_END) {
> +		dev_warn(&info->pdev->dev, "spurious interrupt!!\n");
> +		return IRQ_NONE;
> +	}
> +
> +	switch (i) {
> +	case VBUS_OV_IRQ:
> +		dev_dbg(&info->pdev->dev, "VBUS Over Voltage INTR\n");
> +		break;
> +	case CHARGE_DONE_IRQ:
> +		dev_dbg(&info->pdev->dev, "Charging Done INTR\n");
> +		break;
> +	case CHARGE_CHARGING_IRQ:
> +		dev_dbg(&info->pdev->dev, "Start Charging IRQ\n");
> +		break;
> +	case BAT_SAFE_QUIT_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Quit Safe Mode(restart timer) Charging IRQ\n");
> +		break;
> +	case BAT_SAFE_ENTER_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Enter Safe Mode(timer expire) Charging IRQ\n");
> +		break;
> +	case QCBTU_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Quit Battery Under Temperature(CHRG) INTR\n");
> +		break;
> +	case CBTU_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Hit Battery Under Temperature(CHRG) INTR\n");
> +		break;
> +	case QCBTO_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Quit Battery Over Temperature(CHRG) INTR\n");
> +		break;
> +	case CBTO_IRQ:
> +		dev_dbg(&info->pdev->dev,
> +			"Hit Battery Over Temperature(CHRG) INTR\n");
> +		break;
> +	default:
> +		dev_warn(&info->pdev->dev, "Spurious Interrupt!!!\n");
> +		goto out;
> +	}
> +
> +	power_supply_changed(info->psy_usb);
> +out:
> +	return IRQ_HANDLED;
> +}
> +
> +static void axp288_charger_extcon_evt_worker(struct work_struct *work)
> +{
> +	struct axp288_chrg_info *info =
> +	    container_of(work, struct axp288_chrg_info, cable.work);
> +	int ret, current_limit;
> +	bool changed = false;
> +	struct extcon_dev *edev = info->cable.edev;
> +	bool old_connected = info->cable.connected;
> +
> +	/* Determine cable/charger type */
> +	if (extcon_get_cable_state(edev, AXP288_EXTCON_CABLE_SDP) > 0) {
> +		dev_dbg(&info->pdev->dev, "USB SDP charger connected");
> +		info->cable.connected = true;
> +		info->cable.chg_type = POWER_SUPPLY_TYPE_USB;
> +	} else if (extcon_get_cable_state(edev, AXP288_EXTCON_CABLE_CDP) > 0) {
> +		dev_dbg(&info->pdev->dev, "USB CDP charger connected");
> +		info->cable.connected = true;
> +		info->cable.chg_type = POWER_SUPPLY_TYPE_USB_CDP;
> +	} else if (extcon_get_cable_state(edev, AXP288_EXTCON_CABLE_DCP) > 0) {
> +		dev_dbg(&info->pdev->dev, "USB DCP charger connected");
> +		info->cable.connected = true;
> +		info->cable.chg_type = POWER_SUPPLY_TYPE_USB_DCP;
> +	} else {
> +		if (old_connected)
> +			dev_dbg(&info->pdev->dev,  "USB charger disconnected");
> +		info->cable.connected = false;
> +		info->cable.chg_type = POWER_SUPPLY_TYPE_USB;
> +	}
> +
> +	/* Cable status changed */
> +	if (old_connected != info->cable.connected)
> +		changed = true;
> +
> +	if (!changed)
> +		return;
> +
> +	mutex_lock(&info->lock);
> +
> +	if (info->is_charger_enabled && !info->cable.connected) {
> +		info->enable_charger = false;
> +		ret = axp288_charger_enable_charger(info, info->enable_charger);
> +		if (ret < 0)
> +			dev_err(&info->pdev->dev,
> +				"cannot disable charger (%d)", ret);
> +
> +	} else if (!info->is_charger_enabled && info->cable.connected) {
> +		switch (info->cable.chg_type) {
> +		case POWER_SUPPLY_TYPE_USB:
> +			current_limit = ILIM_500MA;
> +			break;
> +		case POWER_SUPPLY_TYPE_USB_CDP:
> +			current_limit = ILIM_1500MA;
> +			break;
> +		case POWER_SUPPLY_TYPE_USB_DCP:
> +			current_limit = ILIM_2000MA;
> +			break;
> +		default:
> +			/* Unknown */
> +			current_limit = 0;
> +			break;
> +		}
> +
> +		/* Set vbus current limit first, then enable charger */
> +		ret = axp288_charger_set_vbus_inlmt(info, current_limit);
> +		if (ret < 0) {
> +			dev_err(&info->pdev->dev,
> +				"error setting current limit (%d)", ret);
> +		} else {
> +			info->enable_charger = (current_limit > 0);
> +			ret = axp288_charger_enable_charger(info,
> +							info->enable_charger);
> +			if (ret < 0)
> +				dev_err(&info->pdev->dev,
> +					"cannot enable charger (%d)", ret);
> +		}
> +	}
> +
> +	if (changed)
> +		info->health = axp288_get_charger_health(info);
> +
> +	mutex_unlock(&info->lock);
> +
> +	if (changed)
> +		power_supply_changed(info->psy_usb);
> +}
> +
> +static int axp288_charger_handle_cable_evt(struct notifier_block *nb,
> +					  unsigned long event, void *param)
> +{
> +	struct axp288_chrg_info *info =
> +	    container_of(nb, struct axp288_chrg_info, cable.nb);
> +
> +	schedule_work(&info->cable.work);
> +
> +	return NOTIFY_OK;
> +}
> +
> +static void axp288_charger_otg_evt_worker(struct work_struct *work)
> +{
> +	struct axp288_chrg_info *info =
> +	    container_of(work, struct axp288_chrg_info, otg.work);
> +	int ret;
> +
> +	/* Disable VBUS path before enabling the 5V boost */
> +	ret = axp288_charger_vbus_path_select(info, !info->otg.id_short);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "vbus path disable failed\n");
> +}
> +
> +static int axp288_charger_handle_otg_evt(struct notifier_block *nb,
> +				   unsigned long event, void *param)
> +{
> +	struct axp288_chrg_info *info =
> +	    container_of(nb, struct axp288_chrg_info, otg.id_nb);
> +	struct extcon_dev *edev = param;
> +	int usb_host = extcon_get_cable_state(edev, "USB-Host");
> +
> +	dev_dbg(&info->pdev->dev, "external connector USB-Host is %s\n",
> +				usb_host ? "attached" : "detached");
> +
> +	/*
> +	 * Set usb_id_short flag to avoid running charger detection logic
> +	 * in case usb host.
> +	 */
> +	info->otg.id_short = usb_host;
> +	schedule_work(&info->otg.work);
> +
> +	return NOTIFY_OK;
> +}
> +
> +static void charger_init_hw_regs(struct axp288_chrg_info *info)
> +{
> +	int ret, cc, cv;
> +	unsigned int val;
> +
> +	/* Program temperature thresholds */
> +	ret = regmap_write(info->regmap, AXP20X_V_LTF_CHRG, CHRG_VLTFC_0C);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error init V(LTF-charge)\n");
> +
> +	ret = regmap_write(info->regmap, AXP20X_V_HTF_CHRG, CHRG_VHTFC_45C);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error init V(LTF-charge)\n");
> +
> +	/* Do not turn-off charger o/p after charge cycle ends */
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_CHRG_CTRL2,
> +				CNTL2_CHG_OUT_TURNON, 1);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev,
> +			 "error setting charger stay on after charging\n");
> +
> +	/* Enable interrupts */
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_IRQ2_EN,
> +				BAT_IRQ_CFG_BAT_MASK, 1);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error enabling charging IRQs");
> +
> +	ret = regmap_update_bits(info->regmap, AXP20X_IRQ3_EN,
> +				TEMP_IRQ_CFG_MASK, 1);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error enabling temperature IRQs");
> +
> +	/* Setup ending condition for charging to be 10% of I(chrg) */
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_CHRG_CTRL1,
> +				CHRG_CCCV_ITERM_20P, 0);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev, "error setting ending condition\n");
> +
> +	/* Disable OCV-SOC curve calibration */
> +	ret = regmap_update_bits(info->regmap,
> +				AXP20X_CC_CTRL,
> +				FG_CNTL_OCV_ADJ_EN, 0);
> +	if (ret < 0)
> +		dev_warn(&info->pdev->dev,
> +			 "error disabling OCV-SOC calibration\n");
> +
> +	/* Init charging current and voltage */
> +	info->max_cc = info->pdata->max_cc;
> +	info->max_cv = info->pdata->max_cv;
> +
> +	/* Read current charge voltage and current limit */
> +	ret = regmap_read(info->regmap, AXP20X_CHRG_CTRL1, &val);
> +	if (ret < 0) {
> +		/* Assume default if cannot read */
> +		info->cc = info->pdata->def_cc;
> +		info->cv = info->pdata->def_cv;
> +	} else {
> +		/* Determine charge voltage */
> +		cv = (val & CHRG_CCCV_CV_MASK) >> CHRG_CCCV_CV_BIT_POS;
> +		switch (cv) {
> +		case CHRG_CCCV_CV_4100MV:
> +			info->cv = CV_4100MV;
> +			break;
> +		case CHRG_CCCV_CV_4150MV:
> +			info->cv = CV_4150MV;
> +			break;
> +		case CHRG_CCCV_CV_4200MV:
> +			info->cv = CV_4200MV;
> +			break;
> +		case CHRG_CCCV_CV_4350MV:
> +			info->cv = CV_4350MV;
> +			break;
> +		default:
> +			info->cv = INT_MAX;
> +			break;
> +		}
> +
> +		/* Determine charge current limit */
> +		cc = (ret & CHRG_CCCV_CC_MASK) >> CHRG_CCCV_CC_BIT_POS;
> +		cc = (cc * CHRG_CCCV_CC_LSB_RES) + CHRG_CCCV_CC_OFFSET;
> +		info->cc = cc;
> +
> +		/* Program default charging voltage and current */
> +		cc = min(info->pdata->def_cc, info->max_cc);
> +		cv = min(info->pdata->def_cv, info->max_cv);
> +
> +		ret = axp288_charger_set_cc(info, cc);
> +		if (ret < 0)
> +			dev_warn(&info->pdev->dev, "error init cc\n");
> +
> +		ret = axp288_charger_set_cv(info, cv);
> +		if (ret < 0)
> +			dev_warn(&info->pdev->dev, "error init cv\n");
> +	}
> +}
> +
> +static int axp288_charger_probe(struct platform_device *pdev)
> +{
> +	int ret, i, pirq;
> +	struct axp288_chrg_info *info;
> +	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent);
> +	struct power_supply_config charger_cfg = {};
> +
> +	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
> +	if (!info)
> +		return -ENOMEM;
> +
> +	info->pdev = pdev;
> +	info->regmap = axp20x->regmap;
> +	info->regmap_irqc = axp20x->regmap_irqc;
> +	info->pdata = pdev->dev.platform_data;
> +
> +	if (!info->pdata) {
> +		/* TODO: Try ACPI provided pdata via device properties */
> +		if (!device_property_present(&pdev->dev,
> +						"axp288_charger_data\n"))
> +			dev_err(&pdev->dev, "no platform data\n");
> +		return -ENODEV;
> +	}
> +
> +	info->cable.edev = extcon_get_extcon_dev(AXP288_EXTCON_DEV_NAME);
> +	if (info->cable.edev == NULL) {
> +		dev_dbg(&pdev->dev, "%s is not ready, probe deferred\n",
> +			AXP288_EXTCON_DEV_NAME);
> +		return -EPROBE_DEFER;
> +	}
> +
> +	/* Register for extcon notification */
> +	INIT_WORK(&info->cable.work, axp288_charger_extcon_evt_worker);
> +	info->cable.nb.notifier_call = axp288_charger_handle_cable_evt;
> +	ret = extcon_register_notifier(info->cable.edev, &info->cable.nb);
> +	if (ret) {
> +		dev_err(&info->pdev->dev,
> +			"failed to register extcon notifier %d\n", ret);
> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, info);
> +	mutex_init(&info->lock);
> +
> +	/* Register with power supply class */
> +	charger_cfg.drv_data = info;
> +	info->psy_usb = power_supply_register(&pdev->dev, &axp288_charger_desc,
> +						&charger_cfg);
> +	if (IS_ERR(info->psy_usb)) {
> +		dev_err(&pdev->dev, "Can't register charger\n");
> +		ret = PTR_ERR(info->psy_usb);
> +		goto psy_reg_failed;
> +	}
> +
> +	/* Register for OTG notification */
> +	INIT_WORK(&info->otg.work, axp288_charger_otg_evt_worker);
> +	info->otg.id_nb.notifier_call = axp288_charger_handle_otg_evt;
> +	ret = extcon_register_interest(&info->otg.cable, NULL, "USB-Host",
> +				       &info->otg.id_nb);
> +	if (ret)
> +		dev_warn(&pdev->dev, "failed to register otg notifier\n");
> +
> +	if (info->otg.cable.edev)
> +		info->otg.id_short = extcon_get_cable_state(
> +					info->otg.cable.edev, "USB-Host");
> +
> +	/* Register charger interrupts */
> +	for (i = 0; i < CHRG_INTR_END; i++) {
> +		pirq = platform_get_irq(info->pdev, i);
> +		info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq);
> +		if (info->irq[i] < 0) {
> +			dev_warn(&info->pdev->dev,
> +				"regmap_irq get irq failed for IRQ %d: %d\n",
> +				pirq, info->irq[i]);
> +			info->irq[i] = -1;
> +			goto intr_reg_failed;
> +		}
> +		ret = devm_request_threaded_irq(&info->pdev->dev, info->irq[i],
> +					NULL, axp288_charger_irq_thread_handler,
> +					IRQF_ONESHOT, info->pdev->name, info);
> +		if (ret) {
> +			dev_warn(&info->pdev->dev,
> +				"request irq failed for IRQ %d: %d\n",
> +				pirq, info->irq[i]);
> +			goto intr_reg_failed;
> +		}
> +	}
> +
> +	charger_init_hw_regs(info);
> +
> +	return 0;
> +
> +intr_reg_failed:
> +	if (info->otg.cable.edev)
> +		extcon_unregister_interest(&info->otg.cable);
> +	power_supply_unregister(info->psy_usb);
> +psy_reg_failed:
> +	extcon_unregister_notifier(info->cable.edev, &info->cable.nb);
> +	return ret;
> +}
> +
> +static int axp288_charger_remove(struct platform_device *pdev)
> +{
> +	struct axp288_chrg_info *info =  dev_get_drvdata(&pdev->dev);
> +
> +	if (info->otg.cable.edev)
> +		extcon_unregister_interest(&info->otg.cable);
> +
> +	extcon_unregister_notifier(info->cable.edev, &info->cable.nb);
> +	power_supply_unregister(info->psy_usb);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver axp288_charger_driver = {
> +	.probe = axp288_charger_probe,
> +	.remove = axp288_charger_remove,
> +	.driver = {
> +		.name = "axp288_charger",
> +	},
> +};
> +
> +module_platform_driver(axp288_charger_driver);
> +
> +MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>");
> +MODULE_DESCRIPTION("Xpower AXP288 Charger Driver");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/axp20x.h b/include/linux/mfd/axp20x.h
> index dfabd6d..f9030df 100644
> --- a/include/linux/mfd/axp20x.h
> +++ b/include/linux/mfd/axp20x.h
> @@ -275,4 +275,11 @@ struct axp20x_fg_pdata {
>  	int thermistor_curve[MAX_THERM_CURVE_SIZE][2];
>  };
>  
> +struct axp20x_chrg_pdata {
> +	int max_cc;
> +	int max_cv;
> +	int def_cc;
> +	int def_cv;
> +};
> +
>  #endif /* __LINUX_MFD_AXP20X_H */

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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