/* Copyright 2016 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 *
 * Placeholder values for temporary battery pack.
 */

#include "battery.h"
#include "battery_smart.h"
#include "bd9995x.h"
#include "charge_ramp.h"
#include "charge_state.h"
#include "console.h"
#include "ec_commands.h"
#include "extpower.h"
#include "gpio.h"
#include "hooks.h"
#include "util.h"

#define CPRINTS(format, args...) cprints(CC_CHARGER, format, ## args)

/* Shutdown mode parameter to write to manufacturer access register */
#define SB_SHUTDOWN_DATA	0x0010

enum battery_type {
	BATTERY_LG,
	BATTERY_LISHEN,
	BATTERY_SIMPLO,
	BATTERY_TYPE_COUNT,
};

struct board_batt_params {
	const char *manuf_name;
	const struct battery_info *batt_info;
};

/*
 * Set LISHEN as default since the LG precharge current level could cause the
 * LISHEN battery to not accept charge when it's recovering from a fully
 * discharged state.
 */
#define DEFAULT_BATTERY_TYPE BATTERY_LISHEN
static enum battery_present batt_pres_prev = BP_NOT_SURE;
static enum battery_type board_battery_type = BATTERY_TYPE_COUNT;

/*
 * Battery info for LG A50. Note that the fields start_charging_min/max and
 * charging_min/max are not used for the Eve charger. The effective temperature
 * limits are given by discharging_min/max_c.
 */
static const struct battery_info batt_info_lg = {
	.voltage_max		= TARGET_WITH_MARGIN(8800, 5), /* mV */
	.voltage_normal		= 7700,
	.voltage_min		= 6100, /* Add 100mV for charger accuracy */
	.precharge_current	= 256,	/* mA */
	.start_charging_min_c	= 0,
	.start_charging_max_c	= 46,
	.charging_min_c		= 10,
	.charging_max_c		= 50,
	.discharging_min_c	= 0,
	.discharging_max_c	= 60,
};

/*
 * Battery info for LISHEN. Note that the fields start_charging_min/max and
 * charging_min/max are not used for the Eve charger. The effective temperature
 * limits are given by discharging_min/max_c.
 */
static const struct battery_info batt_info_lishen = {
	.voltage_max		= TARGET_WITH_MARGIN(8800, 5), /* mV */
	.voltage_normal		= 7700,
	.voltage_min		= 6100, /* Add 100mV for charger accuracy */
	.precharge_current	= 256,	/* mA */
	.start_charging_min_c	= 0,
	.start_charging_max_c	= 46,
	.charging_min_c		= 10,
	.charging_max_c		= 50,
	.discharging_min_c	= 0,
	.discharging_max_c	= 60,
};

static const struct board_batt_params info[] = {
	[BATTERY_LG] = {
		.manuf_name = "LG A50",
		.batt_info = &batt_info_lg,
	},

	[BATTERY_LISHEN] = {
		.manuf_name = "Lishen A50",
		.batt_info = &batt_info_lishen,
	},

	[BATTERY_SIMPLO] = {
		.manuf_name = "Simplo A50",
		.batt_info = &batt_info_lishen,
	},

};
BUILD_ASSERT(ARRAY_SIZE(info) == BATTERY_TYPE_COUNT);

/* Get type of the battery connected on the board */
static int board_get_battery_type(void)
{
	char name[3];
	int i;

	if (!battery_manufacturer_name(name, sizeof(name))) {
		for (i = 0; i < BATTERY_TYPE_COUNT; i++) {
			if (!strncasecmp(name, info[i].manuf_name,
					 ARRAY_SIZE(name)-1)) {
				board_battery_type = i;
				break;
			}
		}
	}

	return board_battery_type;
}

/*
 * Initialize the battery type for the board.
 *
 * Very first battery info is called by the charger driver to initialize
 * the charger parameters hence initialize the battery type for the board
 * as soon as the I2C is initialized.
 */
static void board_init_battery_type(void)
{
	if (board_get_battery_type() != BATTERY_TYPE_COUNT)
		CPRINTS("found batt: %s", info[board_battery_type].manuf_name);
	else
		CPRINTS("battery not found");
}
DECLARE_HOOK(HOOK_INIT, board_init_battery_type, HOOK_PRIO_INIT_I2C + 1);

const struct battery_info *battery_get_info(void)
{
	return info[board_battery_type == BATTERY_TYPE_COUNT ?
		    DEFAULT_BATTERY_TYPE : board_battery_type].batt_info;
}

int board_cut_off_battery(void)
{
	int rv;

	/* Ship mode command must be sent twice to take effect */
	rv = sb_write(SB_MANUFACTURER_ACCESS, SB_SHUTDOWN_DATA);
	if (rv != EC_SUCCESS)
		return EC_RES_ERROR;

	rv = sb_write(SB_MANUFACTURER_ACCESS, SB_SHUTDOWN_DATA);
	return rv ? EC_RES_ERROR : EC_RES_SUCCESS;
}

enum battery_disconnect_state battery_get_disconnect_state(void)
{
	uint8_t data[6];
	int rv;

	/*
	 * Take note if we find that the battery isn't in disconnect state,
	 * and always return NOT_DISCONNECTED without probing the battery.
	 * This assumes the battery will not go to disconnect state during
	 * runtime.
	 */
	static int not_disconnected;

	if (not_disconnected)
		return BATTERY_NOT_DISCONNECTED;

	if (extpower_is_present()) {
		/* Check if battery charging + discharging is disabled. */
		rv = sb_read_mfgacc(PARAM_OPERATION_STATUS,
				SB_ALT_MANUFACTURER_ACCESS, data, sizeof(data));
		if (rv)
			return BATTERY_DISCONNECT_ERROR;

		if (~data[3] & (BATTERY_DISCHARGING_DISABLED |
				BATTERY_CHARGING_DISABLED)) {
			not_disconnected = 1;
			return BATTERY_NOT_DISCONNECTED;
		}

		/*
		 * Battery is neither charging nor discharging. Verify that
		 * we didn't enter this state due to a safety fault.
		 */
		rv = sb_read_mfgacc(PARAM_SAFETY_STATUS,
				SB_ALT_MANUFACTURER_ACCESS, data, sizeof(data));
		if (rv || data[2] || data[3] || data[4] || data[5])
			return BATTERY_DISCONNECT_ERROR;

		/*
		 * Battery is present and also the status is initialized and
		 * no safety fault, battery is disconnected.
		 */
		if (battery_is_present() == BP_YES)
			return BATTERY_DISCONNECTED;
	}
	not_disconnected = 1;
	return BATTERY_NOT_DISCONNECTED;
}

static int charger_should_discharge_on_ac(struct charge_state_data *curr)
{
	/* Can not discharge on AC without battery */
	if (curr->batt.is_present != BP_YES)
		return 0;

	/* Do not discharge on AC if the battery is still waking up */
	if (!(curr->batt.flags & BATT_FLAG_WANT_CHARGE) &&
		!(curr->batt.status & STATUS_FULLY_CHARGED))
		return 0;

	/*
	 * In light load (<450mA being withdrawn from VSYS) the DCDC of the
	 * charger operates intermittently i.e. DCDC switches continuously
	 * and then stops to regulate the output voltage and current, and
	 * sometimes to prevent reverse current from flowing to the input.
	 * This causes a slight voltage ripple on VSYS that falls in the
	 * audible noise frequency (single digit kHz range). This small
	 * ripple generates audible noise in the output ceramic capacitors
	 * (caps on VSYS and any input of DCDC under VSYS).
	 *
	 * To overcome this issue enable the battery learning operation
	 * and suspend USB charging and DC/DC converter.
	 */
	if ((board_get_version() < 5) && !battery_is_cut_off() &&
		!(curr->batt.flags & BATT_FLAG_WANT_CHARGE) &&
		(curr->batt.status & STATUS_FULLY_CHARGED))
		return 1;

	/*
	 * To avoid inrush current from the external charger, enable
	 * discharge on AC 2till the new charger is detected and charge
	 * detect delay has passed.
	 */
	if (!chg_ramp_is_detected() && curr->batt.state_of_charge > 2)
		return 1;

	return 0;
}

int charger_profile_override(struct charge_state_data *curr)
{
	const struct battery_info *batt_info;
	/* battery temp in 0.1 deg C */
	int bat_temp_c = curr->batt.temperature - 2731;
	int disch_on_ac = charger_should_discharge_on_ac(curr);

	charger_discharge_on_ac(disch_on_ac);

	if (disch_on_ac) {
		curr->state = ST_DISCHARGE;
		return 0;
	}

	batt_info = battery_get_info();
	/* Don't charge if outside of allowable temperature range */
	if (bat_temp_c >= batt_info->charging_max_c * 10 ||
	    bat_temp_c < batt_info->charging_min_c * 10) {
		curr->requested_current = 0;
		curr->requested_voltage = 0;
		curr->batt.flags &= ~BATT_FLAG_WANT_CHARGE;
		curr->state = ST_IDLE;
	}
	return 0;
}

/* Customs options controllable by host command. */
#define PARAM_FASTCHARGE (CS_PARAM_CUSTOM_PROFILE_MIN + 0)

enum ec_status charger_profile_override_get_param(uint32_t param,
						  uint32_t *value)
{
	return EC_RES_INVALID_PARAM;
}

enum ec_status charger_profile_override_set_param(uint32_t param,
						  uint32_t value)
{
	return EC_RES_INVALID_PARAM;
}

enum battery_present battery_hw_present(void)
{
	/* The GPIO is low when the battery is physically present */
	return gpio_get_level(GPIO_BATTERY_PRESENT_L) ? BP_NO : BP_YES;
}

static int battery_init(void)
{
	int batt_status;

	return battery_status(&batt_status) ? 0 :
		!!(batt_status & STATUS_INITIALIZED);
}

/*
 * Physical detection of battery.
 */
enum battery_present battery_is_present(void)
{
	enum battery_present batt_pres;

	/* Get the physical hardware status */
	batt_pres = battery_hw_present();

	/*
	 * Make sure battery status is implemented, I2C transactions are
	 * success & the battery status is Initialized to find out if it
	 * is a working battery and it is not in the cut-off mode.
	 *
	 * If battery I2C fails but VBATT is high, battery is booting from
	 * cut-off mode.
	 *
	 * FETs are turned off after Power Shutdown time.
	 * The device will wake up when a voltage is applied to PACK.
	 * Battery status will be inactive until it is initialized.
	 */
	if (batt_pres == BP_YES && batt_pres_prev != batt_pres &&
	    !battery_is_cut_off() && !battery_init()) {
		batt_pres = BP_NO;
	}

	batt_pres_prev = batt_pres;

	return batt_pres;
}

int board_battery_initialized(void)
{
	return battery_hw_present() == batt_pres_prev;
}