/* * Copyright (c) 2016, Prodys S.L. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This adds support for sbs-charger compilant chips as defined here: * http://sbs-forum.org/specs/sbc110.pdf * * Implemetation based on sbs-battery.c */ #include #include #include #include #include #include #include #include #include #include #include #include #define SBS_CHARGER_REG_SPEC_INFO 0x11 #define SBS_CHARGER_REG_STATUS 0x13 #define SBS_CHARGER_REG_ALARM_WARNING 0x16 #define SBS_CHARGER_STATUS_CHARGE_INHIBITED BIT(0) #define SBS_CHARGER_STATUS_RES_COLD BIT(9) #define SBS_CHARGER_STATUS_RES_HOT BIT(10) #define SBS_CHARGER_STATUS_BATTERY_PRESENT BIT(14) #define SBS_CHARGER_STATUS_AC_PRESENT BIT(15) #define SBS_CHARGER_POLL_TIME 500 struct sbs_info { struct i2c_client *client; struct power_supply *power_supply; struct regmap *regmap; struct delayed_work work; unsigned int last_state; }; static int sbs_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { struct sbs_info *chip = power_supply_get_drvdata(psy); unsigned int reg; reg = chip->last_state; switch (psp) { case POWER_SUPPLY_PROP_PRESENT: val->intval = !!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT); break; case POWER_SUPPLY_PROP_ONLINE: val->intval = !!(reg & SBS_CHARGER_STATUS_AC_PRESENT); break; case POWER_SUPPLY_PROP_STATUS: val->intval = POWER_SUPPLY_STATUS_UNKNOWN; if (!(reg & SBS_CHARGER_STATUS_BATTERY_PRESENT)) val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; else if (reg & SBS_CHARGER_STATUS_AC_PRESENT && !(reg & SBS_CHARGER_STATUS_CHARGE_INHIBITED)) val->intval = POWER_SUPPLY_STATUS_CHARGING; else val->intval = POWER_SUPPLY_STATUS_DISCHARGING; break; case POWER_SUPPLY_PROP_HEALTH: if (reg & SBS_CHARGER_STATUS_RES_COLD) val->intval = POWER_SUPPLY_HEALTH_COLD; if (reg & SBS_CHARGER_STATUS_RES_HOT) val->intval = POWER_SUPPLY_HEALTH_OVERHEAT; else val->intval = POWER_SUPPLY_HEALTH_GOOD; break; default: return -EINVAL; } return 0; } static int sbs_check_state(struct sbs_info *chip) { unsigned int reg; int ret; ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, ®); if (!ret && reg != chip->last_state) { chip->last_state = reg; power_supply_changed(chip->power_supply); return 1; } return 0; } static void sbs_delayed_work(struct work_struct *work) { struct sbs_info *chip = container_of(work, struct sbs_info, work.work); sbs_check_state(chip); schedule_delayed_work(&chip->work, msecs_to_jiffies(SBS_CHARGER_POLL_TIME)); } static irqreturn_t sbs_irq_thread(int irq, void *data) { struct sbs_info *chip = data; int ret; ret = sbs_check_state(chip); return ret ? IRQ_HANDLED : IRQ_NONE; } static enum power_supply_property sbs_properties[] = { POWER_SUPPLY_PROP_STATUS, POWER_SUPPLY_PROP_PRESENT, POWER_SUPPLY_PROP_ONLINE, POWER_SUPPLY_PROP_HEALTH, }; static bool sbs_readable_reg(struct device *dev, unsigned int reg) { return reg >= SBS_CHARGER_REG_SPEC_INFO; } static bool sbs_volatile_reg(struct device *dev, unsigned int reg) { switch (reg) { case SBS_CHARGER_REG_STATUS: return true; } return false; } static const struct regmap_config sbs_regmap = { .reg_bits = 8, .val_bits = 16, .max_register = SBS_CHARGER_REG_ALARM_WARNING, .readable_reg = sbs_readable_reg, .volatile_reg = sbs_volatile_reg, .val_format_endian = REGMAP_ENDIAN_LITTLE, /* since based on SMBus */ }; static const struct power_supply_desc sbs_desc = { .name = "sbs-charger", .type = POWER_SUPPLY_TYPE_MAINS, .properties = sbs_properties, .num_properties = ARRAY_SIZE(sbs_properties), .get_property = sbs_get_property, }; static int sbs_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct power_supply_config psy_cfg = {}; struct sbs_info *chip; int ret, val; chip = devm_kzalloc(&client->dev, sizeof(struct sbs_info), GFP_KERNEL); if (!chip) return -ENOMEM; chip->client = client; psy_cfg.of_node = client->dev.of_node; psy_cfg.drv_data = chip; i2c_set_clientdata(client, chip); chip->regmap = devm_regmap_init_i2c(client, &sbs_regmap); if (IS_ERR(chip->regmap)) return PTR_ERR(chip->regmap); /* * Before we register, we need to make sure we can actually talk * to the battery. */ ret = regmap_read(chip->regmap, SBS_CHARGER_REG_STATUS, &val); if (ret) { dev_err(&client->dev, "Failed to get device status\n"); return ret; } chip->last_state = val; chip->power_supply = devm_power_supply_register(&client->dev, &sbs_desc, &psy_cfg); if (IS_ERR(chip->power_supply)) { dev_err(&client->dev, "Failed to register power supply\n"); return PTR_ERR(chip->power_supply); } /* * The sbs-charger spec doesn't impose the use of an interrupt. So in * the case it wasn't provided we use polling in order get the charger's * status. */ if (client->irq) { ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, sbs_irq_thread, IRQF_TRIGGER_FALLING | IRQF_ONESHOT, dev_name(&client->dev), chip); if (ret) { dev_err(&client->dev, "Failed to request irq, %d\n", ret); return ret; } } else { INIT_DELAYED_WORK(&chip->work, sbs_delayed_work); schedule_delayed_work(&chip->work, msecs_to_jiffies(SBS_CHARGER_POLL_TIME)); } dev_info(&client->dev, "%s: smart charger device registered\n", client->name); return 0; } static int sbs_remove(struct i2c_client *client) { struct sbs_info *chip = i2c_get_clientdata(client); cancel_delayed_work_sync(&chip->work); return 0; } #ifdef CONFIG_OF static const struct of_device_id sbs_dt_ids[] = { { .compatible = "sbs,sbs-charger" }, { }, }; MODULE_DEVICE_TABLE(of, sbs_dt_ids); #endif static const struct i2c_device_id sbs_id[] = { { "sbs-charger", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, sbs_id); static struct i2c_driver sbs_driver = { .probe = sbs_probe, .remove = sbs_remove, .id_table = sbs_id, .driver = { .name = "sbs-charger", .of_match_table = of_match_ptr(sbs_dt_ids), }, }; module_i2c_driver(sbs_driver); MODULE_AUTHOR("Nicolas Saenz Julienne "); MODULE_DESCRIPTION("SBS smart charger driver"); MODULE_LICENSE("GPL v2");