ltc3337.h

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/***************************************************************************/
#ifndef __LTC3337_H__
#define __LTC3337_H__
 
#include <stdint.h>
#include "no_os_util.h"
#include "no_os_i2c.h"
 
#define LTC3337_I2C_ADDR            0x64 // b1100100[r/w] 0xC8, 0xC9
 
#define LTC3337_MAX_TEMP_C          159  //Maximum temperature for alarms
#define LTC3337_MIN_TEMP_C          -41  //Minimum temperature for alarms
#define LTC3337_MAX_PRESCALE        15   //Maximum prescaler value
 
#define LTC3337_OVERFLOW_ALARM_MAX  0xFF //Max value for overflow alarm
 
#define LTC3337_REG_A   0x01 //Prescaler Select, IRQ Clear, Shutdown, Alarm Thresh
 
#define LTC3337_RA_PRESCALE_MSK     NO_OS_GENMASK(3, 0)
#define LTC3337_RA_CLEAR_INT        NO_OS_BIT(4)
#define LTC3337_RA_CNT_CHK      NO_OS_BIT(5)
#define LTC3337_RA_SHTDN        NO_OS_BIT(6)
#define LTC3337_RA_ADC_CONV     NO_OS_BIT(7)
#define LTC3337_RA_ALARM_LVL_MSK    NO_OS_GENMASK(15, 8)
 
#define LTC3337_REG_B   0x02 //Accumulated Charge
 
#define LTC3337_REG_C   0x03 //Status, Temperature
//Use the following definitions for derterming interrupt status
#define LTC3337_RC_OVERFLOW         NO_OS_BIT(0)
#define LTC3337_RC_ALARM_TRIP       NO_OS_BIT(1)
#define LTC3337_RC_ALARM_MIN        NO_OS_BIT(2)
#define LTC3337_RC_ALARM_MAX        NO_OS_BIT(3)
#define LTC3337_RC_ADC_READY        NO_OS_BIT(4)
#define LTC3337_RC_IPK_PIN_MSK      NO_OS_GENMASK(7, 5)
#define LTC3337_RC_DIE_TEMP_MSK     NO_OS_GENMASK(15, 8)
 
#define LTC3337_REG_D   0x04 //BAT_IN V, Ipeak On
#define LTC3337_REG_E   0x05 //BAT_IN V, Ipeak Off
#define LTC3337_REG_F   0x06 //BAT_OUT V, Ipeak On
#define LTC3337_REG_G   0x07 //BAT_OUT V, Ipeak Off
#define LTC3337_BATV_MSK        NO_OS_GENMASK(11, 0)
 
#define LTC3337_REG_H   0x08 //Temp Alarm Config
#define LTC3337_RH_HOT_ALARM_MSK    NO_OS_GENMASK(15, 8)
#define LTC3337_RH_COLD_ALARM_MSK   NO_OS_GENMASK(7, 0)
 
#define LTC3337_VLSB_UV     1465 //1.465 mV = 1465 uV
#define LTC3337_TLSB_MC     784  //0.784 Deg C = 784 mC
#define LTC3337_TEMP_MIN_C  -41
 
#define LTC3337_NUM_IPEAKS  8 //3-bit iPeak Input
 
//Scale values used in integer match to calulate A/nA-hrs from counters
#define LTC3337_NANO_AMP    1000000000
#define LTC3337_CALC_SCALE  10000
#define LTC3337_CALC_TO_WHOLE   (LTC3337_NANO_AMP / LTC3337_CALC_SCALE)
 
//Scale value for converting uV to mV
#define LTC3337_UV_TO_MV_SCALE  1000
 
//Scale Value for converting mC to Deg C
#define LTC3337_MC_TO_C_SCALE   1000

struct ltc3337_dev {
    struct no_os_i2c_desc *i2c_desc;  //I2C device
    uint8_t ipeak_latched;             //iPeak value read at init
    uint16_t latched_reg_a;                //Latched Register A value
};
struct ltc3337_dev {…};

struct ltc3337_init_param {
    struct no_os_i2c_init_param i2c_init;   //I2C Configuration
    uint8_t prescale;                       //Initial device prescaler value
};
struct ltc3337_init_param {…};

struct charge_count_t {
    uint32_t a_hr;  //A-hrs
    uint32_t na_hr;    //nA-hrs
};
struct charge_count_t {…};

enum ltc3337_voltage_src_t {
    BAT_IN_IPEAK_ON,
    BAT_IN_IPEAK_OFF,
    BAT_OUT_IPEAK_ON,
    BAT_OUT_IPEAK_OFF
};
enum ltc3337_voltage_src_t {…};
 
/* Initializes the device instance */
int ltc3337_init(struct ltc3337_dev** dev,
         struct ltc3337_init_param* init_param);
 
/* Removes the device instance */
int ltc3337_remove(struct ltc3337_dev* dev);
 
/* Sets the device prescaler value */
int ltc3337_set_prescaler(struct ltc3337_dev* dev, uint8_t prescale);
 
/* Sets the temperature alarms, in Deg C */
int ltc3337_set_temperature_alarms_c(struct ltc3337_dev* dev, int16_t hot_alarm,
                     int16_t cold_alarm);
 
/* Enabled / Disables the Coulomb counter shutdown */
int ltc3337_set_counter_shutdown(struct ltc3337_dev* dev, uint8_t shutdown_en);
 
/* Sets the couloumb counter alarm threshold */
int ltc3337_set_counter_alarm(struct ltc3337_dev* dev, uint16_t reg_value,
                  uint8_t round_up);
 
/* Manually sets the accumulated charge register */
int ltc3337_set_accumulated_charge(struct ltc3337_dev* dev, uint16_t reg_value,
                   uint8_t round_up);
 
/* Gets the current value of the accumulated charge register */
int ltc3337_get_accumulated_charge(struct ltc3337_dev* dev,
                   struct charge_count_t* value,
                   uint16_t* raw_value);
 
/* Reads the specified voltage source, in millivolts */
int ltc3337_get_voltage_mv(struct ltc3337_dev* dev,
               enum ltc3337_voltage_src_t source,
               uint32_t* value);
 
/* Gets the current die temperature, in Deg C */
int ltc3337_get_temperature_c(struct ltc3337_dev* dev, int16_t* value);
 
/* Gets the device interrupt status, and clears interrupts */
int ltc3337_get_and_clear_interrupts(struct ltc3337_dev* dev,
                     uint16_t* int_field,
                     int16_t* temp_c);
 
/* Calculates a charge register value based on A-Hr units */
int ltc3337_calculate_charge_register(struct ltc3337_dev* dev,
                      struct charge_count_t* charge_a,
                      uint16_t* reg_value);
 
#endif