QPNP 8909 8916 充電相關（2）【轉】
- 2019 年 10 月 8 日
- 筆記
上一篇主要講電池相關的一些知識，上節忘記講了，電池一般分為電量計電池和非電流計電池，電量計電池，就不需要用pmu8916的IC，當然這只是只，不需要BMS來計算soc，而jni層也需要讀取電流計的電池相關屬性。
這一節主要是根據代碼進行相關的分析。
- 先看probe的代碼：
static int qpnp_vm_bms_probe(struct spmi_device *spmi) { ........... .......... ........... .......... //這裡把電池的配置文件dtsi的讀出來，並存到當前的結構體。 rc = set_battery_data(chip); rc = config_battery_data(chip->batt_data); .......... .......... //這個是核心的工作，一個線程，BMS的主要內容在此 INIT_DELAYED_WORK(&chip->monitor_soc_work, monitor_soc_work); .......... .......... //電池一些常規的檢測，主要從PMIC上讀到的相關信息 battery_insertion_check(chip); battery_status_check(chip); /* character device to pass data to the userspace */ rc = register_bms_char_device(chip); if (rc) { pr_err("Unable to regiter '/dev/vm_bms' rc=%dn", rc); goto fail_bms_device; } the_chip = chip; //這個也很重要，我們從上節知道，初值last_ocv_soc是非常重要的，決定着後面的soc估值算法 calculate_initial_soc(chip); //設置和註冊電池的power supply /* setup & register the battery power supply */ chip->bms_psy.name = "bms"; chip->bms_psy.type = POWER_SUPPLY_TYPE_BMS; chip->bms_psy.properties = bms_power_props; chip->bms_psy.num_properties = ARRAY_SIZE(bms_power_props); chip->bms_psy.get_property = qpnp_vm_bms_power_get_property; chip->bms_psy.set_property = qpnp_vm_bms_power_set_property; chip->bms_psy.external_power_changed = qpnp_vm_bms_ext_power_changed; chip->bms_psy.property_is_writeable = qpnp_vm_bms_property_is_writeable; chip->bms_psy.supplied_to = qpnp_vm_bms_supplicants; chip->bms_psy.num_supplicants = ARRAY_SIZE(qpnp_vm_bms_supplicants); rc = power_supply_register(chip->dev, &chip->bms_psy); if (rc < 0) { pr_err("power_supply_register bms failed rc = %dn", rc); goto fail_psy; } ..................... .................... .................... //這裡啟動工作線程 schedule_delayed_work(&chip->monitor_soc_work, 0); .......................... ....................... }
- 分析如何確定初始的last_ocv_uv：
static int calculate_initial_soc(struct qpnp_bms_chip *chip) { ........ ........ //讀當前電池溫度 rc = get_batt_therm(chip, &batt_temp); ............ //讀PON OCV rc = read_and_update_ocv(chip, batt_temp, true); .......... //讀關機保存的soc和last_soc_uv rc = read_shutdown_ocv_soc(chip); //這裡判斷是使用估計soc還是估值soc。如果chip->warm_reset 為真 if (chip->warm_reset) { if (chip->shutdown_soc_invalid) { //這個是dtsi的一個配置選項，若沒有配置， //則不使用關機soc est_ocv = estimate_ocv(chip); //估值soc chip->last_ocv_uv = est_ocv; } else { chip->last_ocv_uv = chip->shutdown_ocv;//使用關機的soc和ocv pr_err("Hyan %d : set chip->last_ocv_uv = %dn", __LINE__, chip->last_ocv_uv); chip->last_soc = chip->shutdown_soc; chip->calculated_soc = lookup_soc_ocv(chip, chip->shutdown_ocv, batt_temp); } } else { if (chip->workaround_flag & WRKARND_PON_OCV_COMP) adjust_pon_ocv(chip, batt_temp); /* !warm_reset use PON OCV only if shutdown SOC is invalid */ chip->calculated_soc = lookup_soc_ocv(chip, chip->last_ocv_uv, batt_temp); if (!chip->shutdown_soc_invalid && (abs(chip->shutdown_soc - chip->calculated_soc) < chip->dt.cfg_shutdown_soc_valid_limit)) { chip->last_ocv_uv = chip->shutdown_ocv; chip->last_soc = chip->shutdown_soc; chip->calculated_soc = lookup_soc_ocv(chip, chip->shutdown_ocv, batt_temp);//使用估值soc } else { chip->shutdown_soc_invalid = true; //使用關機soc } } ............. ............ } //得到PON OCV rc = read_and_update_ocv(chip, batt_temp, true); ocv_uv = convert_vbatt_raw_to_uv(chip, ocv_data, is_pon_ocv); uv = vadc_reading_to_uv(reading, true); //讀ADC值 uv = adjust_vbatt_reading(chip, uv); //轉化為soc_uv rc = qpnp_vbat_sns_comp_result(chip->vadc_dev, &uv, is_pon_ocv); //根據IC的類型，進行溫度補償 //從寄存器中讀到儲存的soc和ocv read_shutdown_ocv_soc rc = qpnp_read_wrapper(chip, (u8 *)&stored_ocv, chip->base + BMS_OCV_REG, 2); rc = qpnp_read_wrapper(chip, &stored_soc, chip->base + BMS_SOC_REG, 1); adjust_pon_ocv(struct qpnp_bms_chip *chip, int batt_temp) rc = qpnp_vadc_read(chip->vadc_dev, DIE_TEMP, &result); pc = interpolate_pc(chip->batt_data->pc_temp_ocv_lut, batt_temp, chip->last_ocv_uv / 1000); //根據ocv和temp，查表得PC(soc)。 rbatt_mohm = get_rbatt(chip, pc, batt_temp); //根據soc和temp，得電池內阻zhi /* convert die_temp to DECIDEGC */ die_temp = (int)result.physical / 100; current_ma = interpolate_current_comp(die_temp); //當前電流 delta_uv = rbatt_mohm * current_ma; chip->last_ocv_uv += delta_uv; //修正last_ocv_uv //這個函數主要根據last_ocv_uv，計算出soc的 lookup_soc_ocv(struct qpnp_bms_chip *chip, int ocv_uv, int batt_temp) //查表得到soc_ocv，soc_cutoff soc_ocv = interpolate_pc(chip->batt_data->pc_temp_ocv_lut, batt_temp, ocv_uv / 1000); soc_cutoff = interpolate_pc(chip->batt_data->pc_temp_ocv_lut, batt_temp, chip->dt.cfg_v_cutoff_uv / 1000); soc_final = DIV_ROUND_CLOSEST(100 * (soc_ocv - soc_cutoff), (100 - soc_cutoff)); if (batt_temp > chip->dt.cfg_low_temp_threshold) iavg_ma = calculate_uuc_iavg(chip); else iavg_ma = chip->current_now / 1000; //查表得到FCC，ACC fcc = interpolate_fcc(chip->batt_data->fcc_temp_lut, batt_temp); acc = interpolate_acc(chip->batt_data->ibat_acc_lut, batt_temp, iavg_ma); //計算出UUC soc_uuc = ((fcc - acc) * 100) / fcc; if (batt_temp > chip->dt.cfg_low_temp_threshold) soc_uuc = adjust_uuc(chip, soc_uuc); //得到soc_acc soc_acc = DIV_ROUND_CLOSEST(100 * (soc_ocv - soc_uuc), (100 - soc_uuc)); soc_final = soc_acc; //這個為上報的soc chip->last_acc = acc;
- 看工作線程，monitor_soc_work(struct work_struct *work)：
static void monitor_soc_work(struct work_struct *work) calculate_delta_time(&chip->tm_sec, &chip->delta_time_s); rc = get_batt_therm(chip, &batt_temp); new_soc = lookup_soc_ocv(chip, chip->last_ocv_uv,batt_temp); new_soc = clamp_soc_based_on_voltage(chip, new_soc); report_vm_bms_soc(chip);//上報事件，上層得到消息，調用qpnp_vm_bms_power_get_property，獲取相關的屬性，計算出 last_ocv_uv,並通過qpnp_vm_bms_power_set_property方法，設置last_ocv_uv，並啟動monitor_soc_work。
- 待續
