diff options
Diffstat (limited to 'drivers/power')
-rw-r--r-- | drivers/power/supply/Kconfig | 13 | ||||
-rw-r--r-- | drivers/power/supply/Makefile | 1 | ||||
-rw-r--r-- | drivers/power/supply/sbs-manager.c | 323 |
3 files changed, 337 insertions, 0 deletions
diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index 5ab90c1f3f7c..1899b3ec6bec 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -184,6 +184,19 @@ config CHARGER_SBS help Say Y to include support for SBS compilant battery chargers. +config MANAGER_SBS + tristate "Smart Battery System Manager" + depends on I2C && I2C_MUX + help + Say Y here to include support for Smart Battery System Manager + ICs. The driver reports online and charging status via sysfs. + It presents itself also as I2C mux which allows to bind + smart battery driver to its ports. + Supported is for example LTC1760. + + This driver can also be built as a module. If so, the module will be + called sbs-manager. + config BATTERY_BQ27XXX tristate "BQ27xxx battery driver" help diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile index 621a19058fec..3e8f49a17770 100644 --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_BATTERY_IPAQ_MICRO) += ipaq_micro_battery.o obj-$(CONFIG_BATTERY_WM97XX) += wm97xx_battery.o obj-$(CONFIG_BATTERY_SBS) += sbs-battery.o obj-$(CONFIG_CHARGER_SBS) += sbs-charger.o +obj-$(CONFIG_MANAGER_SBS) += sbs-manager.o obj-$(CONFIG_BATTERY_BQ27XXX) += bq27xxx_battery.o obj-$(CONFIG_BATTERY_BQ27XXX_I2C) += bq27xxx_battery_i2c.o obj-$(CONFIG_BATTERY_BQ27XXX_HDQ) += bq27xxx_battery_hdq.o diff --git a/drivers/power/supply/sbs-manager.c b/drivers/power/supply/sbs-manager.c new file mode 100644 index 000000000000..47c09a178411 --- /dev/null +++ b/drivers/power/supply/sbs-manager.c @@ -0,0 +1,323 @@ +/* + * Driver for SBS compliant Smart Battery System Managers + * + * The device communicates via i2c at address 0x0a and multiplexes access to up + * to four smart batteries at address 0x0b. + * + * Via sysfs interface the online state and charge type are presented. + * + * Datasheet SBSM: http://sbs-forum.org/specs/sbsm100b.pdf + * Datasheet LTC1760: http://cds.linear.com/docs/en/datasheet/1760fb.pdf + * + * Karl-Heinz Schneider <karl-heinz@schneider-inet.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/i2c-mux.h> +#include <linux/power_supply.h> + +#define SBSM_MAX_BATS 4 +#define SBSM_RETRY_CNT 3 + +/* registers addresses */ +#define SBSM_CMD_BATSYSSTATE 0x01 +#define SBSM_CMD_BATSYSSTATECONT 0x02 +#define SBSM_CMD_BATSYSINFO 0x04 +#define SBSM_CMD_LTC 0x3c + +#define SBSM_MASK_BAT_SUPPORTED GENMASK(3, 0) +#define SBSM_MASK_CHARGE_BAT GENMASK(7, 4) +#define SBSM_BIT_AC_PRESENT BIT(0) +#define SBSM_BIT_TURBO BIT(7) + +#define SBSM_SMB_BAT_OFFSET 11 +struct sbsm_data { + struct i2c_client *client; + struct i2c_mux_core *muxc; + + struct power_supply *psy; + + u8 cur_chan; /* currently selected channel */ + bool is_ltc1760; /* special capabilities */ +}; + +static enum power_supply_property sbsm_props[] = { + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_CHARGE_TYPE, +}; + +static int sbsm_read_word(struct i2c_client *client, u8 address) +{ + int reg, retries; + + for (retries = SBSM_RETRY_CNT; retries > 0; retries--) { + reg = i2c_smbus_read_word_data(client, address); + if (reg >= 0) + break; + } + + if (reg < 0) { + dev_err(&client->dev, "failed to read register 0x%02x\n", + address); + } + + return reg; +} + +static int sbsm_write_word(struct i2c_client *client, u8 address, u16 word) +{ + int ret, retries; + + for (retries = SBSM_RETRY_CNT; retries > 0; retries--) { + ret = i2c_smbus_write_word_data(client, address, word); + if (ret >= 0) + break; + } + if (ret < 0) + dev_err(&client->dev, "failed to write to register 0x%02x\n", + address); + + return ret; +} + +static int sbsm_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct sbsm_data *data = power_supply_get_drvdata(psy); + int regval = 0; + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + regval = sbsm_read_word(data->client, SBSM_CMD_BATSYSSTATECONT); + if (regval < 0) + return regval; + val->intval = !!(regval & SBSM_BIT_AC_PRESENT); + break; + + case POWER_SUPPLY_PROP_CHARGE_TYPE: + regval = sbsm_read_word(data->client, SBSM_CMD_BATSYSSTATE); + if (regval < 0) + return regval; + + if ((regval & SBSM_MASK_CHARGE_BAT) == 0) { + val->intval = POWER_SUPPLY_CHARGE_TYPE_NONE; + return 0; + } + val->intval = POWER_SUPPLY_CHARGE_TYPE_TRICKLE; + + if (data->is_ltc1760) { + /* charge mode fast if turbo is active */ + regval = sbsm_read_word(data->client, SBSM_CMD_LTC); + if (regval < 0) + return regval; + else if (regval & SBSM_BIT_TURBO) + val->intval = POWER_SUPPLY_CHARGE_TYPE_FAST; + } + break; + + default: + return -EINVAL; + } + + return 0; +} + +static int sbsm_prop_is_writeable(struct power_supply *psy, + enum power_supply_property psp) +{ + struct sbsm_data *data = power_supply_get_drvdata(psy); + + return (psp == POWER_SUPPLY_PROP_CHARGE_TYPE) && data->is_ltc1760; +} + +static int sbsm_set_property(struct power_supply *psy, + enum power_supply_property psp, + const union power_supply_propval *val) +{ + struct sbsm_data *data = power_supply_get_drvdata(psy); + int ret = -EINVAL; + u16 regval; + + switch (psp) { + case POWER_SUPPLY_PROP_CHARGE_TYPE: + /* write 1 to TURBO if type fast is given */ + if (!data->is_ltc1760) + break; + regval = val->intval == + POWER_SUPPLY_CHARGE_TYPE_FAST ? SBSM_BIT_TURBO : 0; + ret = sbsm_write_word(data->client, SBSM_CMD_LTC, regval); + break; + + default: + break; + } + + return ret; +} + +/* + * Switch to battery + * Parameter chan is directly the content of SMB_BAT* nibble + */ +static int sbsm_select(struct i2c_mux_core *muxc, u32 chan) +{ + struct sbsm_data *data = i2c_mux_priv(muxc); + struct device *dev = &data->client->dev; + int ret = 0; + u16 reg; + + if (data->cur_chan == chan) + return ret; + + /* chan goes from 1 ... 4 */ + reg = 1 << BIT(SBSM_SMB_BAT_OFFSET + chan); + ret = sbsm_write_word(data->client, SBSM_CMD_BATSYSSTATE, reg); + if (ret) + dev_err(dev, "Failed to select channel %i\n", chan); + else + data->cur_chan = chan; + + return ret; +} + +static const struct power_supply_desc sbsm_default_psy_desc = { + .type = POWER_SUPPLY_TYPE_MAINS, + .properties = sbsm_props, + .num_properties = ARRAY_SIZE(sbsm_props), + .get_property = &sbsm_get_property, + .set_property = &sbsm_set_property, + .property_is_writeable = &sbsm_prop_is_writeable, +}; + +static int sbsm_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); + struct sbsm_data *data; + struct device *dev = &client->dev; + struct power_supply_desc *psy_desc; + struct power_supply_config psy_cfg = {}; + int ret = 0, i, supported_bats; + + /* Device listens only at address 0x0a */ + if (client->addr != 0x0a) + return -EINVAL; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WORD_DATA)) + return -EPFNOSUPPORT; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + i2c_set_clientdata(client, data); + + data->client = client; + data->is_ltc1760 = !!strstr(id->name, "ltc1760"); + + ret = sbsm_read_word(client, SBSM_CMD_BATSYSINFO); + if (ret < 0) + return ret; + supported_bats = ret & SBSM_MASK_BAT_SUPPORTED; + + data->muxc = i2c_mux_alloc(adapter, dev, SBSM_MAX_BATS, 0, + I2C_MUX_LOCKED, &sbsm_select, NULL); + if (!data->muxc) { + dev_err(dev, "failed to alloc i2c mux\n"); + ret = -ENOMEM; + goto err_mux_alloc; + } + data->muxc->priv = data; + + /* register muxed i2c channels. One for each supported battery */ + for (i = 0; i < SBSM_MAX_BATS; ++i) { + if (supported_bats & BIT(i)) { + ret = i2c_mux_add_adapter(data->muxc, 0, i + 1, 0); + if (ret) + break; + } + } + if (ret) { + dev_err(dev, "failed to register i2c mux channel %d\n", i + 1); + goto err_mux_register; + } + + psy_desc = devm_kmemdup(dev, &sbsm_default_psy_desc, + sizeof(struct power_supply_desc), + GFP_KERNEL); + if (!psy_desc) { + ret = -ENOMEM; + goto err_psy; + } + + psy_desc->name = devm_kasprintf(dev, GFP_KERNEL, "sbsm-%s", + dev_name(&client->dev)); + if (!psy_desc->name) { + ret = -ENOMEM; + goto err_psy; + } + + psy_cfg.drv_data = data; + psy_cfg.of_node = dev->of_node; + data->psy = devm_power_supply_register(dev, psy_desc, &psy_cfg); + if (IS_ERR(data->psy)) { + ret = PTR_ERR(data->psy); + dev_err(dev, "failed to register power supply %s\n", + psy_desc->name); + goto err_psy; + } + + return 0; + +err_psy: +err_mux_register: + i2c_mux_del_adapters(data->muxc); + +err_mux_alloc: + return ret; +} + +static int sbsm_remove(struct i2c_client *client) +{ + struct sbsm_data *data = i2c_get_clientdata(client); + + i2c_mux_del_adapters(data->muxc); + return 0; +} + +static const struct i2c_device_id sbsm_ids[] = { + { "sbs-manager", 0 }, + { "ltc1760", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, sbsm_ids); + +#ifdef CONFIG_OF +static const struct of_device_id sbsm_dt_ids[] = { + { .compatible = "sbs,sbs-manager" }, + { .compatible = "lltc,ltc1760" }, + { } +}; +MODULE_DEVICE_TABLE(of, sbsm_dt_ids); +#endif + +static struct i2c_driver sbsm_driver = { + .driver = { + .name = "sbsm", + .of_match_table = of_match_ptr(sbsm_dt_ids), + }, + .probe = sbsm_probe, + .remove = sbsm_remove, + .id_table = sbsm_ids +}; +module_i2c_driver(sbsm_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Karl-Heinz Schneider <karl-heinz@schneider-inet.de>"); +MODULE_DESCRIPTION("SBSM Smart Battery System Manager"); |