diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c index 307e0995ca3c..93007cb202f0 100644 --- a/drivers/power/supply/power_supply_core.c +++ b/drivers/power/supply/power_supply_core.c @@ -570,7 +570,7 @@ int power_supply_get_battery_info(struct power_supply *psy, { struct device_node *battery_np; const char *value; - int err; + int err, len, index; info->energy_full_design_uwh = -EINVAL; info->charge_full_design_uah = -EINVAL; @@ -581,6 +581,12 @@ int power_supply_get_battery_info(struct power_supply *psy, info->constant_charge_voltage_max_uv = -EINVAL; info->factory_internal_resistance_uohm = -EINVAL; + for (index = 0; index < POWER_SUPPLY_OCV_TEMP_MAX; index++) { + info->ocv_table[index] = NULL; + info->ocv_temp[index] = -EINVAL; + info->ocv_table_size[index] = -EINVAL; + } + if (!psy->of_node) { dev_warn(&psy->dev, "%s currently only supports devicetree\n", __func__); @@ -620,10 +626,139 @@ int power_supply_get_battery_info(struct power_supply *psy, of_property_read_u32(battery_np, "factory-internal-resistance-micro-ohms", &info->factory_internal_resistance_uohm); + len = of_property_count_u32_elems(battery_np, "ocv-capacity-celsius"); + if (len < 0 && len != -EINVAL) { + return len; + } else if (len > POWER_SUPPLY_OCV_TEMP_MAX) { + dev_err(&psy->dev, "Too many temperature values\n"); + return -EINVAL; + } else if (len > 0) { + of_property_read_u32_array(battery_np, "ocv-capacity-celsius", + info->ocv_temp, len); + } + + for (index = 0; index < len; index++) { + struct power_supply_battery_ocv_table *table; + char *propname; + const __be32 *list; + int i, tab_len, size; + + propname = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d", index); + list = of_get_property(battery_np, propname, &size); + if (!list || !size) { + dev_err(&psy->dev, "failed to get %s\n", propname); + kfree(propname); + power_supply_put_battery_info(psy, info); + return -EINVAL; + } + + kfree(propname); + tab_len = size / (2 * sizeof(__be32)); + info->ocv_table_size[index] = tab_len; + + table = info->ocv_table[index] = + devm_kcalloc(&psy->dev, tab_len, sizeof(*table), GFP_KERNEL); + if (!info->ocv_table[index]) { + power_supply_put_battery_info(psy, info); + return -ENOMEM; + } + + for (i = 0; i < tab_len; i++) { + table[i].ocv = be32_to_cpu(*list++); + table[i].capacity = be32_to_cpu(*list++); + } + } + return 0; } EXPORT_SYMBOL_GPL(power_supply_get_battery_info); +void power_supply_put_battery_info(struct power_supply *psy, + struct power_supply_battery_info *info) +{ + int i; + + for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) { + if (info->ocv_table[i]) + devm_kfree(&psy->dev, info->ocv_table[i]); + } +} +EXPORT_SYMBOL_GPL(power_supply_put_battery_info); + +/** + * power_supply_ocv2cap_simple() - find the battery capacity + * @table: Pointer to battery OCV lookup table + * @table_len: OCV table length + * @ocv: Current OCV value + * + * This helper function is used to look up battery capacity according to + * current OCV value from one OCV table, and the OCV table must be ordered + * descending. + * + * Return: the battery capacity. + */ +int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table, + int table_len, int ocv) +{ + int i, cap, tmp; + + for (i = 0; i < table_len; i++) + if (ocv > table[i].ocv) + break; + + if (i > 0 && i < table_len) { + tmp = (table[i - 1].capacity - table[i].capacity) * + (ocv - table[i].ocv); + tmp /= table[i - 1].ocv - table[i].ocv; + cap = tmp + table[i].capacity; + } else if (i == 0) { + cap = table[0].capacity; + } else { + cap = table[table_len - 1].capacity; + } + + return cap; +} +EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple); + +struct power_supply_battery_ocv_table * +power_supply_find_ocv2cap_table(struct power_supply_battery_info *info, + int temp, int *table_len) +{ + int best_temp_diff = INT_MAX, temp_diff; + u8 i, best_index = 0; + + if (!info->ocv_table[0]) + return NULL; + + for (i = 0; i < POWER_SUPPLY_OCV_TEMP_MAX; i++) { + temp_diff = abs(info->ocv_temp[i] - temp); + + if (temp_diff < best_temp_diff) { + best_temp_diff = temp_diff; + best_index = i; + } + } + + *table_len = info->ocv_table_size[best_index]; + return info->ocv_table[best_index]; +} +EXPORT_SYMBOL_GPL(power_supply_find_ocv2cap_table); + +int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info, + int ocv, int temp) +{ + struct power_supply_battery_ocv_table *table; + int table_len; + + table = power_supply_find_ocv2cap_table(info, temp, &table_len); + if (!table) + return -EINVAL; + + return power_supply_ocv2cap_simple(table, table_len, ocv); +} +EXPORT_SYMBOL_GPL(power_supply_batinfo_ocv2cap); + int power_supply_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h index d089566828be..84fe93f674a0 100644 --- a/include/linux/power_supply.h +++ b/include/linux/power_supply.h @@ -309,6 +309,13 @@ struct power_supply_info { int use_for_apm; }; +struct power_supply_battery_ocv_table { + int ocv; /* microVolts */ + int capacity; /* percent */ +}; + +#define POWER_SUPPLY_OCV_TEMP_MAX 20 + /* * This is the recommended struct to manage static battery parameters, * populated by power_supply_get_battery_info(). Most platform drivers should @@ -327,6 +334,9 @@ struct power_supply_battery_info { int constant_charge_current_max_ua; /* microAmps */ int constant_charge_voltage_max_uv; /* microVolts */ int factory_internal_resistance_uohm; /* microOhms */ + int ocv_temp[POWER_SUPPLY_OCV_TEMP_MAX];/* celsius */ + struct power_supply_battery_ocv_table *ocv_table[POWER_SUPPLY_OCV_TEMP_MAX]; + int ocv_table_size[POWER_SUPPLY_OCV_TEMP_MAX]; }; extern struct atomic_notifier_head power_supply_notifier; @@ -350,6 +360,15 @@ devm_power_supply_get_by_phandle(struct device *dev, const char *property) extern int power_supply_get_battery_info(struct power_supply *psy, struct power_supply_battery_info *info); +extern void power_supply_put_battery_info(struct power_supply *psy, + struct power_supply_battery_info *info); +extern int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table, + int table_len, int ocv); +extern struct power_supply_battery_ocv_table * +power_supply_find_ocv2cap_table(struct power_supply_battery_info *info, + int temp, int *table_len); +extern int power_supply_batinfo_ocv2cap(struct power_supply_battery_info *info, + int ocv, int temp); extern void power_supply_changed(struct power_supply *psy); extern int power_supply_am_i_supplied(struct power_supply *psy); extern int power_supply_set_input_current_limit_from_supplier(