// SPDX-License-Identifier: GPL-2.0 /* * Fuel gauge driver for CellWise 2013 / 2015 * * Copyright (C) 2012, RockChip * Copyright (C) 2020, Tobias Schramm * * Authors: xuhuicong * Authors: Tobias Schramm */ #include #include #include #include #include #include #include #include #include #include #include #include #define CW2015_SIZE_BATINFO 64 #define CW2015_RESET_TRIES 5 #define CW2015_REG_VERSION 0x00 #define CW2015_REG_VCELL 0x02 #define CW2015_REG_SOC 0x04 #define CW2015_REG_RRT_ALERT 0x06 #define CW2015_REG_CONFIG 0x08 #define CW2015_REG_MODE 0x0A #define CW2015_REG_BATINFO 0x10 #define CW2015_MODE_SLEEP_MASK GENMASK(7, 6) #define CW2015_MODE_SLEEP (0x03 << 6) #define CW2015_MODE_NORMAL (0x00 << 6) #define CW2015_MODE_QUICK_START (0x03 << 4) #define CW2015_MODE_RESTART (0x0f << 0) #define CW2015_CONFIG_UPDATE_FLG (0x01 << 1) #define CW2015_ATHD(x) ((x) << 3) #define CW2015_MASK_ATHD GENMASK(7, 3) #define CW2015_MASK_SOC GENMASK(12, 0) /* reset gauge of no valid state of charge could be polled for 40s */ #define CW2015_BAT_SOC_ERROR_MS (40 * MSEC_PER_SEC) /* reset gauge if state of charge stuck for half an hour during charging */ #define CW2015_BAT_CHARGING_STUCK_MS (1800 * MSEC_PER_SEC) /* poll interval from CellWise GPL Android driver example */ #define CW2015_DEFAULT_POLL_INTERVAL_MS 8000 #define CW2015_AVERAGING_SAMPLES 3 struct cw_battery { struct device *dev; struct workqueue_struct *battery_workqueue; struct delayed_work battery_delay_work; struct regmap *regmap; struct power_supply *rk_bat; struct power_supply_battery_info battery; u8 *bat_profile; bool charger_attached; bool battery_changed; int soc; int voltage_mv; int status; int time_to_empty; int charge_count; u32 poll_interval_ms; u8 alert_level; unsigned int read_errors; unsigned int charge_stuck_cnt; }; static int cw_read_word(struct cw_battery *cw_bat, u8 reg, u16 *val) { __be16 value; int ret; ret = regmap_bulk_read(cw_bat->regmap, reg, &value, sizeof(value)); if (ret) return ret; *val = be16_to_cpu(value); return 0; } static int cw_update_profile(struct cw_battery *cw_bat) { int ret; unsigned int reg_val; u8 reset_val; /* make sure gauge is not in sleep mode */ ret = regmap_read(cw_bat->regmap, CW2015_REG_MODE, ®_val); if (ret) return ret; reset_val = reg_val; if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) { dev_err(cw_bat->dev, "Gauge is in sleep mode, can't update battery info\n"); return -EINVAL; } /* write new battery info */ ret = regmap_raw_write(cw_bat->regmap, CW2015_REG_BATINFO, cw_bat->bat_profile, CW2015_SIZE_BATINFO); if (ret) return ret; /* set config update flag */ reg_val |= CW2015_CONFIG_UPDATE_FLG; reg_val &= ~CW2015_MASK_ATHD; reg_val |= CW2015_ATHD(cw_bat->alert_level); ret = regmap_write(cw_bat->regmap, CW2015_REG_CONFIG, reg_val); if (ret) return ret; /* reset gauge to apply new battery profile */ reset_val &= ~CW2015_MODE_RESTART; reg_val = reset_val | CW2015_MODE_RESTART; ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reg_val); if (ret) return ret; /* wait for gauge to reset */ msleep(20); /* clear reset flag */ ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val); if (ret) return ret; /* wait for gauge to become ready */ ret = regmap_read_poll_timeout(cw_bat->regmap, CW2015_REG_SOC, reg_val, reg_val <= 100, 10 * USEC_PER_MSEC, 10 * USEC_PER_SEC); if (ret) dev_err(cw_bat->dev, "Gauge did not become ready after profile upload\n"); else dev_dbg(cw_bat->dev, "Battery profile updated\n"); return ret; } static int cw_init(struct cw_battery *cw_bat) { int ret; unsigned int reg_val = CW2015_MODE_SLEEP; if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) { reg_val = CW2015_MODE_NORMAL; ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reg_val); if (ret) return ret; } ret = regmap_read(cw_bat->regmap, CW2015_REG_CONFIG, ®_val); if (ret) return ret; if ((reg_val & CW2015_MASK_ATHD) != CW2015_ATHD(cw_bat->alert_level)) { dev_dbg(cw_bat->dev, "Setting new alert level\n"); reg_val &= ~CW2015_MASK_ATHD; reg_val |= ~CW2015_ATHD(cw_bat->alert_level); ret = regmap_write(cw_bat->regmap, CW2015_REG_CONFIG, reg_val); if (ret) return ret; } ret = regmap_read(cw_bat->regmap, CW2015_REG_CONFIG, ®_val); if (ret) return ret; if (!(reg_val & CW2015_CONFIG_UPDATE_FLG)) { dev_dbg(cw_bat->dev, "Battery profile not present, uploading battery profile\n"); if (cw_bat->bat_profile) { ret = cw_update_profile(cw_bat); if (ret) { dev_err(cw_bat->dev, "Failed to upload battery profile\n"); return ret; } } else { dev_warn(cw_bat->dev, "No profile specified, continuing without profile\n"); } } else if (cw_bat->bat_profile) { u8 bat_info[CW2015_SIZE_BATINFO]; ret = regmap_raw_read(cw_bat->regmap, CW2015_REG_BATINFO, bat_info, CW2015_SIZE_BATINFO); if (ret) { dev_err(cw_bat->dev, "Failed to read stored battery profile\n"); return ret; } if (memcmp(bat_info, cw_bat->bat_profile, CW2015_SIZE_BATINFO)) { dev_warn(cw_bat->dev, "Replacing stored battery profile\n"); ret = cw_update_profile(cw_bat); if (ret) return ret; } } else { dev_warn(cw_bat->dev, "Can't check current battery profile, no profile provided\n"); } dev_dbg(cw_bat->dev, "Battery profile configured\n"); return 0; } static int cw_power_on_reset(struct cw_battery *cw_bat) { int ret; unsigned char reset_val; reset_val = CW2015_MODE_SLEEP; ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val); if (ret) return ret; /* wait for gauge to enter sleep */ msleep(20); reset_val = CW2015_MODE_NORMAL; ret = regmap_write(cw_bat->regmap, CW2015_REG_MODE, reset_val); if (ret) return ret; ret = cw_init(cw_bat); if (ret) return ret; return 0; } #define HYSTERESIS(current, previous, up, down) \ (((current) < (previous) + (up)) && ((current) > (previous) - (down))) static int cw_get_soc(struct cw_battery *cw_bat) { unsigned int soc; int ret; ret = regmap_read(cw_bat->regmap, CW2015_REG_SOC, &soc); if (ret) return ret; if (soc > 100) { int max_error_cycles = CW2015_BAT_SOC_ERROR_MS / cw_bat->poll_interval_ms; dev_err(cw_bat->dev, "Invalid SoC %d%%\n", soc); cw_bat->read_errors++; if (cw_bat->read_errors > max_error_cycles) { dev_warn(cw_bat->dev, "Too many invalid SoC reports, resetting gauge\n"); cw_power_on_reset(cw_bat); cw_bat->read_errors = 0; } return cw_bat->soc; } cw_bat->read_errors = 0; /* Reset gauge if stuck while charging */ if (cw_bat->status == POWER_SUPPLY_STATUS_CHARGING && soc == cw_bat->soc) { int max_stuck_cycles = CW2015_BAT_CHARGING_STUCK_MS / cw_bat->poll_interval_ms; cw_bat->charge_stuck_cnt++; if (cw_bat->charge_stuck_cnt > max_stuck_cycles) { dev_warn(cw_bat->dev, "SoC stuck @%u%%, resetting gauge\n", soc); cw_power_on_reset(cw_bat); cw_bat->charge_stuck_cnt = 0; } } else { cw_bat->charge_stuck_cnt = 0; } /* Ignore voltage dips during charge */ if (cw_bat->charger_attached && HYSTERESIS(soc, cw_bat->soc, 0, 3)) soc = cw_bat->soc; /* Ignore voltage spikes during discharge */ if (!cw_bat->charger_attached && HYSTERESIS(soc, cw_bat->soc, 3, 0)) soc = cw_bat->soc; return soc; } static int cw_get_voltage(struct cw_battery *cw_bat) { int ret, i, voltage_mv; u16 reg_val; u32 avg = 0; for (i = 0; i < CW2015_AVERAGING_SAMPLES; i++) { ret = cw_read_word(cw_bat, CW2015_REG_VCELL, ®_val); if (ret) return ret; avg += reg_val; } avg /= CW2015_AVERAGING_SAMPLES; /* * 305 uV per ADC step * Use 312 / 1024 as efficient approximation of 305 / 1000 * Negligible error of 0.1% */ voltage_mv = avg * 312 / 1024; dev_dbg(cw_bat->dev, "Read voltage: %d mV, raw=0x%04x\n", voltage_mv, reg_val); return voltage_mv; } static int cw_get_time_to_empty(struct cw_battery *cw_bat) { int ret; u16 value16; ret = cw_read_word(cw_bat, CW2015_REG_RRT_ALERT, &value16); if (ret) return ret; return value16 & CW2015_MASK_SOC; } static void cw_update_charge_status(struct cw_battery *cw_bat) { int ret; ret = power_supply_am_i_supplied(cw_bat->rk_bat); if (ret < 0) { dev_warn(cw_bat->dev, "Failed to get supply state: %d\n", ret); } else { bool charger_attached; charger_attached = !!ret; if (cw_bat->charger_attached != charger_attached) { cw_bat->battery_changed = true; if (charger_attached) cw_bat->charge_count++; } cw_bat->charger_attached = charger_attached; } } static void cw_update_soc(struct cw_battery *cw_bat) { int soc; soc = cw_get_soc(cw_bat); if (soc < 0) dev_err(cw_bat->dev, "Failed to get SoC from gauge: %d\n", soc); else if (cw_bat->soc != soc) { cw_bat->soc = soc; cw_bat->battery_changed = true; } } static void cw_update_voltage(struct cw_battery *cw_bat) { int voltage_mv; voltage_mv = cw_get_voltage(cw_bat); if (voltage_mv < 0) dev_err(cw_bat->dev, "Failed to get voltage from gauge: %d\n", voltage_mv); else cw_bat->voltage_mv = voltage_mv; } static void cw_update_status(struct cw_battery *cw_bat) { int status = POWER_SUPPLY_STATUS_DISCHARGING; if (cw_bat->charger_attached) { if (cw_bat->soc >= 100) status = POWER_SUPPLY_STATUS_FULL; else status = POWER_SUPPLY_STATUS_CHARGING; } if (cw_bat->status != status) cw_bat->battery_changed = true; cw_bat->status = status; } static void cw_update_time_to_empty(struct cw_battery *cw_bat) { int time_to_empty; time_to_empty = cw_get_time_to_empty(cw_bat); if (time_to_empty < 0) dev_err(cw_bat->dev, "Failed to get time to empty from gauge: %d\n", time_to_empty); else if (cw_bat->time_to_empty != time_to_empty) { cw_bat->time_to_empty = time_to_empty; cw_bat->battery_changed = true; } } static void cw_bat_work(struct work_struct *work) { struct delayed_work *delay_work; struct cw_battery *cw_bat; int ret; unsigned int reg_val; delay_work = to_delayed_work(work); cw_bat = container_of(delay_work, struct cw_battery, battery_delay_work); ret = regmap_read(cw_bat->regmap, CW2015_REG_MODE, ®_val); if (ret) { dev_err(cw_bat->dev, "Failed to read mode from gauge: %d\n", ret); } else { if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) { int i; for (i = 0; i < CW2015_RESET_TRIES; i++) { if (!cw_power_on_reset(cw_bat)) break; } } cw_update_soc(cw_bat); cw_update_voltage(cw_bat); cw_update_charge_status(cw_bat); cw_update_status(cw_bat); cw_update_time_to_empty(cw_bat); } dev_dbg(cw_bat->dev, "charger_attached = %d\n", cw_bat->charger_attached); dev_dbg(cw_bat->dev, "status = %d\n", cw_bat->status); dev_dbg(cw_bat->dev, "soc = %d%%\n", cw_bat->soc); dev_dbg(cw_bat->dev, "voltage = %dmV\n", cw_bat->voltage_mv); if (cw_bat->battery_changed) power_supply_changed(cw_bat->rk_bat); cw_bat->battery_changed = false; queue_delayed_work(cw_bat->battery_workqueue, &cw_bat->battery_delay_work, msecs_to_jiffies(cw_bat->poll_interval_ms)); } static bool cw_battery_valid_time_to_empty(struct cw_battery *cw_bat) { return cw_bat->time_to_empty > 0 && cw_bat->time_to_empty < CW2015_MASK_SOC && cw_bat->status == POWER_SUPPLY_STATUS_DISCHARGING; } static int cw_battery_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct cw_battery *cw_bat; cw_bat = power_supply_get_drvdata(psy); switch (psp) { case POWER_SUPPLY_PROP_CAPACITY: val->intval = cw_bat->soc; break; case POWER_SUPPLY_PROP_STATUS: val->intval = cw_bat->status; break; case POWER_SUPPLY_PROP_PRESENT: val->intval = !!cw_bat->voltage_mv; break; case POWER_SUPPLY_PROP_VOLTAGE_NOW: val->intval = cw_bat->voltage_mv * 1000; break; case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW: if (cw_battery_valid_time_to_empty(cw_bat)) val->intval = cw_bat->time_to_empty * 60; else val->intval = 0; break; case POWER_SUPPLY_PROP_TECHNOLOGY: val->intval = POWER_SUPPLY_TECHNOLOGY_LION; break; case POWER_SUPPLY_PROP_CHARGE_COUNTER: val->intval = cw_bat->charge_count; break; case POWER_SUPPLY_PROP_CHARGE_FULL: case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: if (cw_bat->battery.charge_full_design_uah > 0) val->intval = cw_bat->battery.charge_full_design_uah; else val->intval = 0; break; case POWER_SUPPLY_PROP_CHARGE_NOW: val->intval = cw_bat->battery.charge_full_design_uah; val->intval = val->intval * cw_bat->soc / 100; break; case POWER_SUPPLY_PROP_CURRENT_NOW: if (cw_battery_valid_time_to_empty(cw_bat) && cw_bat->battery.charge_full_design_uah > 0) { /* calculate remaining capacity */ val->intval = cw_bat->battery.charge_full_design_uah; val->intval = val->intval * cw_bat->soc / 100; /* estimate current based on time to empty */ val->intval = 60 * val->intval / cw_bat->time_to_empty; } else { val->intval = 0; } break; default: break; } return 0; } static enum power_supply_property cw_battery_properties[] = { POWER_SUPPLY_PROP_CAPACITY, POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_VOLTAGE_NOW, POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW, POWER_SUPPLY_PROP_TECHNOLOGY, POWER_SUPPLY_PROP_CHARGE_COUNTER, POWER_SUPPLY_PROP_CHARGE_FULL, POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, POWER_SUPPLY_PROP_CHARGE_NOW, POWER_SUPPLY_PROP_CURRENT_NOW, }; static const struct power_supply_desc cw2015_bat_desc = { .name = "cw2015-battery", .type = POWER_SUPPLY_TYPE_BATTERY, .properties = cw_battery_properties, .num_properties = ARRAY_SIZE(cw_battery_properties), .get_property = cw_battery_get_property, }; static int cw2015_parse_properties(struct cw_battery *cw_bat) { struct device *dev = cw_bat->dev; int length; int ret; length = device_property_count_u8(dev, "cellwise,battery-profile"); if (length < 0) { dev_warn(cw_bat->dev, "No battery-profile found, using current flash contents\n"); } else if (length != CW2015_SIZE_BATINFO) { dev_err(cw_bat->dev, "battery-profile must be %d bytes\n", CW2015_SIZE_BATINFO); return -EINVAL; } else { cw_bat->bat_profile = devm_kzalloc(dev, length, GFP_KERNEL); if (!cw_bat->bat_profile) return -ENOMEM; ret = device_property_read_u8_array(dev, "cellwise,battery-profile", cw_bat->bat_profile, length); if (ret) return ret; } ret = device_property_read_u32(dev, "cellwise,monitor-interval-ms", &cw_bat->poll_interval_ms); if (ret) { dev_dbg(cw_bat->dev, "Using default poll interval\n"); cw_bat->poll_interval_ms = CW2015_DEFAULT_POLL_INTERVAL_MS; } return 0; } static const struct regmap_range regmap_ranges_rd_yes[] = { regmap_reg_range(CW2015_REG_VERSION, CW2015_REG_VERSION), regmap_reg_range(CW2015_REG_VCELL, CW2015_REG_CONFIG), regmap_reg_range(CW2015_REG_MODE, CW2015_REG_MODE), regmap_reg_range(CW2015_REG_BATINFO, CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1), }; static const struct regmap_access_table regmap_rd_table = { .yes_ranges = regmap_ranges_rd_yes, .n_yes_ranges = 4, }; static const struct regmap_range regmap_ranges_wr_yes[] = { regmap_reg_range(CW2015_REG_RRT_ALERT, CW2015_REG_CONFIG), regmap_reg_range(CW2015_REG_MODE, CW2015_REG_MODE), regmap_reg_range(CW2015_REG_BATINFO, CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1), }; static const struct regmap_access_table regmap_wr_table = { .yes_ranges = regmap_ranges_wr_yes, .n_yes_ranges = 3, }; static const struct regmap_range regmap_ranges_vol_yes[] = { regmap_reg_range(CW2015_REG_VCELL, CW2015_REG_SOC + 1), }; static const struct regmap_access_table regmap_vol_table = { .yes_ranges = regmap_ranges_vol_yes, .n_yes_ranges = 1, }; static const struct regmap_config cw2015_regmap_config = { .reg_bits = 8, .val_bits = 8, .rd_table = ®map_rd_table, .wr_table = ®map_wr_table, .volatile_table = ®map_vol_table, .max_register = CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1, }; static int cw_bat_probe(struct i2c_client *client) { int ret; struct cw_battery *cw_bat; struct power_supply_config psy_cfg = { 0 }; cw_bat = devm_kzalloc(&client->dev, sizeof(*cw_bat), GFP_KERNEL); if (!cw_bat) return -ENOMEM; i2c_set_clientdata(client, cw_bat); cw_bat->dev = &client->dev; cw_bat->soc = 1; ret = cw2015_parse_properties(cw_bat); if (ret) { dev_err(cw_bat->dev, "Failed to parse cw2015 properties\n"); return ret; } cw_bat->regmap = devm_regmap_init_i2c(client, &cw2015_regmap_config); if (IS_ERR(cw_bat->regmap)) { dev_err(cw_bat->dev, "Failed to allocate regmap: %ld\n", PTR_ERR(cw_bat->regmap)); return PTR_ERR(cw_bat->regmap); } ret = cw_init(cw_bat); if (ret) { dev_err(cw_bat->dev, "Init failed: %d\n", ret); return ret; } psy_cfg.drv_data = cw_bat; psy_cfg.fwnode = dev_fwnode(cw_bat->dev); cw_bat->rk_bat = devm_power_supply_register(&client->dev, &cw2015_bat_desc, &psy_cfg); if (IS_ERR(cw_bat->rk_bat)) { /* try again if this happens */ dev_err_probe(&client->dev, PTR_ERR(cw_bat->rk_bat), "Failed to register power supply\n"); return PTR_ERR(cw_bat->rk_bat); } ret = power_supply_get_battery_info(cw_bat->rk_bat, &cw_bat->battery); if (ret) { dev_warn(cw_bat->dev, "No monitored battery, some properties will be missing\n"); } cw_bat->battery_workqueue = create_singlethread_workqueue("rk_battery"); INIT_DELAYED_WORK(&cw_bat->battery_delay_work, cw_bat_work); queue_delayed_work(cw_bat->battery_workqueue, &cw_bat->battery_delay_work, msecs_to_jiffies(10)); return 0; } static int __maybe_unused cw_bat_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct cw_battery *cw_bat = i2c_get_clientdata(client); cancel_delayed_work_sync(&cw_bat->battery_delay_work); return 0; } static int __maybe_unused cw_bat_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct cw_battery *cw_bat = i2c_get_clientdata(client); queue_delayed_work(cw_bat->battery_workqueue, &cw_bat->battery_delay_work, 0); return 0; } static SIMPLE_DEV_PM_OPS(cw_bat_pm_ops, cw_bat_suspend, cw_bat_resume); static int cw_bat_remove(struct i2c_client *client) { struct cw_battery *cw_bat = i2c_get_clientdata(client); cancel_delayed_work_sync(&cw_bat->battery_delay_work); power_supply_put_battery_info(cw_bat->rk_bat, &cw_bat->battery); return 0; } static const struct i2c_device_id cw_bat_id_table[] = { { "cw2015", 0 }, { } }; static const struct of_device_id cw2015_of_match[] = { { .compatible = "cellwise,cw2015" }, { } }; MODULE_DEVICE_TABLE(of, cw2015_of_match); static struct i2c_driver cw_bat_driver = { .driver = { .name = "cw2015", .of_match_table = cw2015_of_match, .pm = &cw_bat_pm_ops, }, .probe_new = cw_bat_probe, .remove = cw_bat_remove, .id_table = cw_bat_id_table, }; module_i2c_driver(cw_bat_driver); MODULE_AUTHOR("xhc"); MODULE_AUTHOR("Tobias Schramm "); MODULE_DESCRIPTION("cw2015/cw2013 battery driver"); MODULE_LICENSE("GPL");