path: root/drivers/power/supply/cpcap-battery.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Battery driver for CPCAP PMIC
 *
 * Copyright (C) 2017 Tony Lindgren <tony@atomide.com>
 *
 * Some parts of the code based on earlier Motorola mapphone Linux kernel
 * drivers:
 *
 * Copyright (C) 2009-2010 Motorola, Inc.
 */

#include <linux/delay.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/reboot.h>
#include <linux/regmap.h>
#include <linux/nvmem-consumer.h>
#include <linux/moduleparam.h>

#include <linux/iio/consumer.h>
#include <linux/iio/types.h>
#include <linux/mfd/motorola-cpcap.h>

/*
 * Register bit defines for CPCAP_REG_BPEOL. Some of these seem to
 * map to MC13783UG.pdf "Table 5-19. Register 13, Power Control 0"
 * to enable BATTDETEN, LOBAT and EOL features. We currently use
 * LOBAT interrupts instead of EOL.
 */
#define CPCAP_REG_BPEOL_BIT_EOL9	BIT(9)	/* Set for EOL irq */
#define CPCAP_REG_BPEOL_BIT_EOL8	BIT(8)	/* Set for EOL irq */
#define CPCAP_REG_BPEOL_BIT_UNKNOWN7	BIT(7)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN6	BIT(6)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN5	BIT(5)
#define CPCAP_REG_BPEOL_BIT_EOL_MULTI	BIT(4)	/* Set for multiple EOL irqs */
#define CPCAP_REG_BPEOL_BIT_UNKNOWN3	BIT(3)
#define CPCAP_REG_BPEOL_BIT_UNKNOWN2	BIT(2)
#define CPCAP_REG_BPEOL_BIT_BATTDETEN	BIT(1)	/* Enable battery detect */
#define CPCAP_REG_BPEOL_BIT_EOLSEL	BIT(0)	/* BPDET = 0, EOL = 1 */

/*
 * Register bit defines for CPCAP_REG_CCC1. These seem similar to the twl6030
 * coulomb counter registers rather than the mc13892 registers. Both twl6030
 * and mc13892 set bits 2 and 1 to reset and clear registers. But mc13892
 * sets bit 0 to start the coulomb counter while twl6030 sets bit 0 to stop
 * the coulomb counter like cpcap does. So for now, we use the twl6030 style
 * naming for the registers.
 */
#define CPCAP_REG_CCC1_ACTIVE_MODE1	BIT(4)	/* Update rate */
#define CPCAP_REG_CCC1_ACTIVE_MODE0	BIT(3)	/* Update rate */
#define CPCAP_REG_CCC1_AUTOCLEAR	BIT(2)	/* Resets sample registers */
#define CPCAP_REG_CCC1_CAL_EN		BIT(1)	/* Clears after write in 1s */
#define CPCAP_REG_CCC1_PAUSE		BIT(0)	/* Stop counters, allow write */
#define CPCAP_REG_CCC1_RESET_MASK	(CPCAP_REG_CCC1_AUTOCLEAR | \
					 CPCAP_REG_CCC1_CAL_EN)

#define CPCAP_REG_CCCC2_RATE1		BIT(5)
#define CPCAP_REG_CCCC2_RATE0		BIT(4)
#define CPCAP_REG_CCCC2_ENABLE		BIT(3)

#define CPCAP_BATTERY_CC_SAMPLE_PERIOD_MS	250

#define CPCAP_BATTERY_EB41_HW4X_ID 0x9E
#define CPCAP_BATTERY_BW8X_ID 0x98

enum {
	CPCAP_BATTERY_IIO_BATTDET,
	CPCAP_BATTERY_IIO_VOLTAGE,
	CPCAP_BATTERY_IIO_CHRG_CURRENT,
	CPCAP_BATTERY_IIO_BATT_CURRENT,
	CPCAP_BATTERY_IIO_NR,
};

enum cpcap_battery_irq_action {
	CPCAP_BATTERY_IRQ_ACTION_NONE,
	CPCAP_BATTERY_IRQ_ACTION_CC_CAL_DONE,
	CPCAP_BATTERY_IRQ_ACTION_BATTERY_LOW,
	CPCAP_BATTERY_IRQ_ACTION_POWEROFF,
};

struct cpcap_interrupt_desc {
	const char *name;
	struct list_head node;
	int irq;
	enum cpcap_battery_irq_action action;
};

struct cpcap_battery_config {
	int cd_factor;
	struct power_supply_info info;
	struct power_supply_battery_info bat;
};

struct cpcap_coulomb_counter_data {
	s32 sample;		/* 24 or 32 bits */
	s32 accumulator;
	s16 offset;		/* 9 bits */
	s16 integrator;		/* 13 or 16 bits */
};

enum cpcap_battery_state {
	CPCAP_BATTERY_STATE_PREVIOUS,
	CPCAP_BATTERY_STATE_LATEST,
	CPCAP_BATTERY_STATE_EMPTY,
	CPCAP_BATTERY_STATE_FULL,
	CPCAP_BATTERY_STATE_NR,
};

struct cpcap_battery_state_data {
	int voltage;
	int current_ua;
	int counter_uah;
	int temperature;
	ktime_t time;
	struct cpcap_coulomb_counter_data cc;
};

struct cpcap_battery_ddata {
	struct device *dev;
	struct regmap *reg;
	struct list_head irq_list;
	struct iio_channel *channels[CPCAP_BATTERY_IIO_NR];
	struct power_supply *psy;
	struct cpcap_battery_config config;
	struct cpcap_battery_state_data state[CPCAP_BATTERY_STATE_NR];
	u32 cc_lsb;		/* μAms per LSB */
	atomic_t active;
	int charge_full;
	int status;
	u16 vendor;
	bool check_nvmem;
	unsigned int is_full:1;
};

#define CPCAP_NO_BATTERY	-400

static bool ignore_temperature_probe;
module_param(ignore_temperature_probe, bool, 0660);

static struct cpcap_battery_state_data *
cpcap_battery_get_state(struct cpcap_battery_ddata *ddata,
			enum cpcap_battery_state state)
{
	if (state >= CPCAP_BATTERY_STATE_NR)
		return NULL;

	return &ddata->state[state];
}

static struct cpcap_battery_state_data *
cpcap_battery_latest(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_LATEST);
}

static struct cpcap_battery_state_data *
cpcap_battery_previous(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_PREVIOUS);
}

static struct cpcap_battery_state_data *
cpcap_battery_get_empty(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_EMPTY);
}

static struct cpcap_battery_state_data *
cpcap_battery_get_full(struct cpcap_battery_ddata *ddata)
{
	return cpcap_battery_get_state(ddata, CPCAP_BATTERY_STATE_FULL);
}

static int cpcap_charger_battery_temperature(struct cpcap_battery_ddata *ddata,
					     int *value)
{
	struct iio_channel *channel;
	int error;

	channel = ddata->channels[CPCAP_BATTERY_IIO_BATTDET];
	error = iio_read_channel_processed(channel, value);
	if