Hi, On Sun, Sep 06, 2020 at 10:51:01PM +0300, Dmitry Osipenko wrote: > This patch adds battery gauge driver for Acer Iconia Tab A500 device. > The battery gauge function is provided via the Embedded Controller, > which is found on the Acer A500. > > Signed-off-by: Dmitry Osipenko > --- Reviewed-by: Sebastian Reichel -- Sebastian > drivers/power/supply/Kconfig | 6 + > drivers/power/supply/Makefile | 1 + > drivers/power/supply/acer_a500_battery.c | 297 +++++++++++++++++++++++ > 3 files changed, 304 insertions(+) > create mode 100644 drivers/power/supply/acer_a500_battery.c > > diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig > index a4657484f38b..21257a81b55b 100644 > --- a/drivers/power/supply/Kconfig > +++ b/drivers/power/supply/Kconfig > @@ -760,4 +760,10 @@ config RN5T618_POWER > This driver can also be built as a module. If so, the module will be > called rn5t618_power. > > +config BATTERY_ACER_A500 > + tristate "Acer Iconia Tab A500 battery driver" > + depends on MFD_ACER_A500_EC > + help > + Say Y to include support for Acer Iconia Tab A500 battery fuel gauge. > + > endif # POWER_SUPPLY > diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile > index 293d4a5d80d3..d0f1b77c5c49 100644 > --- a/drivers/power/supply/Makefile > +++ b/drivers/power/supply/Makefile > @@ -97,3 +97,4 @@ obj-$(CONFIG_CHARGER_BD70528) += bd70528-charger.o > obj-$(CONFIG_CHARGER_BD99954) += bd99954-charger.o > obj-$(CONFIG_CHARGER_WILCO) += wilco-charger.o > obj-$(CONFIG_RN5T618_POWER) += rn5t618_power.o > +obj-$(CONFIG_BATTERY_ACER_A500) += acer_a500_battery.o > diff --git a/drivers/power/supply/acer_a500_battery.c b/drivers/power/supply/acer_a500_battery.c > new file mode 100644 > index 000000000000..93135933c8af > --- /dev/null > +++ b/drivers/power/supply/acer_a500_battery.c > @@ -0,0 +1,297 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Battery driver for Acer Iconia Tab A500. > + * > + * Copyright 2020 GRATE-driver project. > + * > + * Based on downstream driver from Acer Inc. > + * Based on NVIDIA Gas Gauge driver for SBS Compliant Batteries. > + * > + * Copyright (c) 2010, NVIDIA Corporation. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +enum { > + REG_CAPACITY, > + REG_VOLTAGE, > + REG_CURRENT, > + REG_DESIGN_CAPACITY, > + REG_TEMPERATURE, > +}; > + > +#define EC_DATA(_reg, _psp) { \ > + .psp = POWER_SUPPLY_PROP_ ## _psp, \ > + .reg = _reg, \ > +} > + > +static const struct battery_register { > + enum power_supply_property psp; > + unsigned int reg; > +} ec_data[] = { > + [REG_CAPACITY] = EC_DATA(0x00, CAPACITY), > + [REG_VOLTAGE] = EC_DATA(0x01, VOLTAGE_NOW), > + [REG_CURRENT] = EC_DATA(0x03, CURRENT_NOW), > + [REG_DESIGN_CAPACITY] = EC_DATA(0x08, CHARGE_FULL_DESIGN), > + [REG_TEMPERATURE] = EC_DATA(0x0a, TEMP), > +}; > + > +static const enum power_supply_property a500_battery_properties[] = { > + POWER_SUPPLY_PROP_CAPACITY, > + POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN, > + POWER_SUPPLY_PROP_CURRENT_NOW, > + POWER_SUPPLY_PROP_PRESENT, > + POWER_SUPPLY_PROP_STATUS, > + POWER_SUPPLY_PROP_TECHNOLOGY, > + POWER_SUPPLY_PROP_TEMP, > + POWER_SUPPLY_PROP_VOLTAGE_NOW, > +}; > + > +struct a500_battery { > + struct delayed_work poll_work; > + struct power_supply *psy; > + struct regmap *rmap; > + unsigned int capacity; > +}; > + > +static bool a500_battery_update_capacity(struct a500_battery *bat) > +{ > + unsigned int capacity; > + int err; > + > + err = regmap_read(bat->rmap, ec_data[REG_CAPACITY].reg, &capacity); > + if (err) > + return false; > + > + /* capacity can be >100% even if max value is 100% */ > + capacity = min(capacity, 100u); > + > + if (bat->capacity != capacity) { > + bat->capacity = capacity; > + return true; > + } > + > + return false; > +} > + > +static int a500_battery_get_status(struct a500_battery *bat) > +{ > + if (bat->capacity < 100) { > + if (power_supply_am_i_supplied(bat->psy)) > + return POWER_SUPPLY_STATUS_CHARGING; > + else > + return POWER_SUPPLY_STATUS_DISCHARGING; > + } > + > + return POWER_SUPPLY_STATUS_FULL; > +} > + > +static void a500_battery_unit_adjustment(struct device *dev, > + enum power_supply_property psp, > + union power_supply_propval *val) > +{ > + const unsigned int base_unit_conversion = 1000; > + const unsigned int temp_kelvin_to_celsius = 2731; > + > + switch (psp) { > + case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: > + case POWER_SUPPLY_PROP_CURRENT_NOW: > + case POWER_SUPPLY_PROP_VOLTAGE_NOW: > + val->intval *= base_unit_conversion; > + break; > + > + case POWER_SUPPLY_PROP_TEMP: > + val->intval -= temp_kelvin_to_celsius; > + break; > + > + case POWER_SUPPLY_PROP_PRESENT: > + val->intval = !!val->intval; > + break; > + > + default: > + dev_dbg(dev, > + "%s: no need for unit conversion %d\n", __func__, psp); > + } > +} > + > +static int a500_battery_get_ec_data_index(struct device *dev, > + enum power_supply_property psp) > +{ > + unsigned int i; > + > + /* > + * DESIGN_CAPACITY register always returns a non-zero value if > + * battery is connected and zero if disconnected, hence we'll use > + * it for judging the battery presence. > + */ > + if (psp == POWER_SUPPLY_PROP_PRESENT) > + psp = POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN; > + > + for (i = 0; i < ARRAY_SIZE(ec_data); i++) > + if (psp == ec_data[i].psp) > + return i; > + > + dev_dbg(dev, "%s: invalid property %u\n", __func__, psp); > + > + return -EINVAL; > +} > + > +static int a500_battery_get_property(struct power_supply *psy, > + enum power_supply_property psp, > + union power_supply_propval *val) > +{ > + struct a500_battery *bat = power_supply_get_drvdata(psy); > + struct device *dev = psy->dev.parent; > + int ret = 0; > + > + switch (psp) { > + case POWER_SUPPLY_PROP_STATUS: > + val->intval = a500_battery_get_status(bat); > + break; > + > + case POWER_SUPPLY_PROP_TECHNOLOGY: > + val->intval = POWER_SUPPLY_TECHNOLOGY_LION; > + break; > + > + case POWER_SUPPLY_PROP_CAPACITY: > + a500_battery_update_capacity(bat); > + val->intval = bat->capacity; > + break; > + > + case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: > + case POWER_SUPPLY_PROP_CURRENT_NOW: > + case POWER_SUPPLY_PROP_VOLTAGE_NOW: > + case POWER_SUPPLY_PROP_PRESENT: > + case POWER_SUPPLY_PROP_TEMP: > + ret = a500_battery_get_ec_data_index(dev, psp); > + if (ret < 0) > + break; > + > + ret = regmap_read(bat->rmap, ec_data[ret].reg, &val->intval); > + break; > + > + default: > + dev_err(dev, "%s: invalid property %u\n", __func__, psp); > + return -EINVAL; > + } > + > + if (!ret) { > + /* convert units to match requirements of power supply class */ > + a500_battery_unit_adjustment(dev, psp, val); > + } > + > + dev_dbg(dev, "%s: property = %d, value = %x\n", > + __func__, psp, val->intval); > + > + /* return NODATA for properties if battery not presents */ > + if (ret) > + return -ENODATA; > + > + return 0; > +} > + > +static void a500_battery_poll_work(struct work_struct *work) > +{ > + struct a500_battery *bat; > + bool capacity_changed; > + > + bat = container_of(work, struct a500_battery, poll_work.work); > + capacity_changed = a500_battery_update_capacity(bat); > + > + if (capacity_changed) > + power_supply_changed(bat->psy); > + > + /* continuously send uevent notification */ > + schedule_delayed_work(&bat->poll_work, 30 * HZ); > +} > + > +static const struct power_supply_desc a500_battery_desc = { > + .name = "ec-battery", > + .type = POWER_SUPPLY_TYPE_BATTERY, > + .properties = a500_battery_properties, > + .get_property = a500_battery_get_property, > + .num_properties = ARRAY_SIZE(a500_battery_properties), > + .external_power_changed = power_supply_changed, > +}; > + > +static int a500_battery_probe(struct platform_device *pdev) > +{ > + struct power_supply_config psy_cfg = {}; > + struct a500_battery *bat; > + > + bat = devm_kzalloc(&pdev->dev, sizeof(*bat), GFP_KERNEL); > + if (!bat) > + return -ENOMEM; > + > + platform_set_drvdata(pdev, bat); > + > + psy_cfg.of_node = pdev->dev.parent->of_node; > + psy_cfg.drv_data = bat; > + > + bat->rmap = dev_get_regmap(pdev->dev.parent, "KB930"); > + if (!bat->rmap) > + return -EINVAL; > + > + bat->psy = devm_power_supply_register_no_ws(&pdev->dev, > + &a500_battery_desc, > + &psy_cfg); > + if (IS_ERR(bat->psy)) > + return dev_err_probe(&pdev->dev, PTR_ERR(bat->psy), > + "failed to register battery\n"); > + > + INIT_DELAYED_WORK(&bat->poll_work, a500_battery_poll_work); > + schedule_delayed_work(&bat->poll_work, HZ); > + > + return 0; > +} > + > +static int a500_battery_remove(struct platform_device *pdev) > +{ > + struct a500_battery *bat = dev_get_drvdata(&pdev->dev); > + > + cancel_delayed_work_sync(&bat->poll_work); > + > + return 0; > +} > + > +static int __maybe_unused a500_battery_suspend(struct device *dev) > +{ > + struct a500_battery *bat = dev_get_drvdata(dev); > + > + cancel_delayed_work_sync(&bat->poll_work); > + > + return 0; > +} > + > +static int __maybe_unused a500_battery_resume(struct device *dev) > +{ > + struct a500_battery *bat = dev_get_drvdata(dev); > + > + schedule_delayed_work(&bat->poll_work, HZ); > + > + return 0; > +} > + > +static SIMPLE_DEV_PM_OPS(a500_battery_pm_ops, > + a500_battery_suspend, a500_battery_resume); > + > +static struct platform_driver a500_battery_driver = { > + .driver = { > + .name = "acer-a500-iconia-battery", > + .pm = &a500_battery_pm_ops, > + }, > + .probe = a500_battery_probe, > + .remove = a500_battery_remove, > +}; > +module_platform_driver(a500_battery_driver); > + > +MODULE_DESCRIPTION("Battery gauge driver for Acer Iconia Tab A500"); > +MODULE_AUTHOR("Dmitry Osipenko "); > +MODULE_ALIAS("platform:acer-a500-iconia-battery"); > +MODULE_LICENSE("GPL"); > -- > 2.27.0 >