diff options
Diffstat (limited to 'drivers/power/bq24735-charger.c')
| -rw-r--r-- | drivers/power/bq24735-charger.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/power/bq24735-charger.c b/drivers/power/bq24735-charger.c new file mode 100644 index 00000000000..d022b823305 --- /dev/null +++ b/drivers/power/bq24735-charger.c @@ -0,0 +1,419 @@ +/* + * Battery charger driver for TI BQ24735 + * + * Copyright (c) 2013, NVIDIA CORPORATION. All rights reserved. + * + * 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; + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include <linux/err.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/power_supply.h> +#include <linux/slab.h> + +#include <linux/power/bq24735-charger.h> + +#define BQ24735_CHG_OPT 0x12 +#define BQ24735_CHG_OPT_CHARGE_DISABLE (1 << 0) +#define BQ24735_CHG_OPT_AC_PRESENT (1 << 4) +#define BQ24735_CHARGE_CURRENT 0x14 +#define BQ24735_CHARGE_CURRENT_MASK 0x1fc0 +#define BQ24735_CHARGE_VOLTAGE 0x15 +#define BQ24735_CHARGE_VOLTAGE_MASK 0x7ff0 +#define BQ24735_INPUT_CURRENT 0x3f +#define BQ24735_INPUT_CURRENT_MASK 0x1f80 +#define BQ24735_MANUFACTURER_ID 0xfe +#define BQ24735_DEVICE_ID 0xff + +struct bq24735 { + struct power_supply charger; + struct i2c_client *client; + struct bq24735_platform *pdata; +}; + +static inline struct bq24735 *to_bq24735(struct power_supply *psy) +{ + return container_of(psy, struct bq24735, charger); +} + +static enum power_supply_property bq24735_charger_properties[] = { + POWER_SUPPLY_PROP_ONLINE, +}; + +static inline int bq24735_write_word(struct i2c_client *client, u8 reg, + u16 value) +{ + return i2c_smbus_write_word_data(client, reg, le16_to_cpu(value)); +} + +static inline int bq24735_read_word(struct i2c_client *client, u8 reg) +{ + s32 ret = i2c_smbus_read_word_data(client, reg); + + return ret < 0 ? ret : le16_to_cpu(ret); +} + +static int bq24735_update_word(struct i2c_client *client, u8 reg, + u16 mask, u16 value) +{ + unsigned int tmp; + int ret; + + ret = bq24735_read_word(client, reg); + if (ret < 0) + return ret; + + tmp = ret & ~mask; + tmp |= value & mask; + + return bq24735_write_word(client, reg, tmp); +} + +static inline int bq24735_enable_charging(struct bq24735 *charger) +{ + return bq24735_update_word(charger->client, BQ24735_CHG_OPT, + BQ24735_CHG_OPT_CHARGE_DISABLE, + ~BQ24735_CHG_OPT_CHARGE_DISABLE); +} + +static inline int bq24735_disable_charging(struct bq24735 *charger) +{ + return bq24735_update_word(charger->client, BQ24735_CHG_OPT, + BQ24735_CHG_OPT_CHARGE_DISABLE, + BQ24735_CHG_OPT_CHARGE_DISABLE); +} + +static int bq24735_config_charger(struct bq24735 *charger) +{ + struct bq24735_platform *pdata = charger->pdata; + int ret; + u16 value; + + if (pdata->charge_current) { + value = pdata->charge_current & BQ24735_CHARGE_CURRENT_MASK; + + ret = bq24735_write_word(charger->client, + BQ24735_CHARGE_CURRENT, value); + if (ret < 0) { + dev_err(&charger->client->dev, + "Failed to write charger current : %d\n", + ret); + return ret; + } + } + + if (pdata->charge_voltage) { + value = pdata->charge_voltage & BQ24735_CHARGE_VOLTAGE_MASK; + + ret = bq24735_write_word(charger->client, + BQ24735_CHARGE_VOLTAGE, value); + if (ret < 0) { + dev_err(&charger->client->dev, + "Failed to write charger voltage : %d\n", + ret); + return ret; + } + } + + if (pdata->input_current) { + value = pdata->input_current & BQ24735_INPUT_CURRENT_MASK; + + ret = bq24735_write_word(charger->client, + BQ24735_INPUT_CURRENT, value); + if (ret < 0) { + dev_err(&charger->client->dev, + "Failed to write input current : %d\n", + ret); + return ret; + } + } + + return 0; +} + +static bool bq24735_charger_is_present(struct bq24735 *charger) +{ + struct bq24735_platform *pdata = charger->pdata; + int ret; + + if (pdata->status_gpio_valid) { + ret = gpio_get_value_cansleep(pdata->status_gpio); + return ret ^= pdata->status_gpio_active_low == 0; + } else { + int ac = 0; + + ac = bq24735_read_word(charger->client, BQ24735_CHG_OPT); + if (ac < 0) { + dev_err(&charger->client->dev, + "Failed to read charger options : %d\n", + ac); + return false; + } + return (ac & BQ24735_CHG_OPT_AC_PRESENT) ? true : false; + } + + return false; +} + +static irqreturn_t bq24735_charger_isr(int irq, void *devid) +{ + struct power_supply *psy = devid; + struct bq24735 *charger = to_bq24735(psy); + + if (bq24735_charger_is_present(charger)) + bq24735_enable_charging(charger); + else + bq24735_disable_charging(charger); + + power_supply_changed(psy); + + return IRQ_HANDLED; +} + +static int bq24735_charger_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct bq24735 *charger; + + charger = container_of(psy, struct bq24735, charger); + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + val->intval = bq24735_charger_is_present(charger) ? 1 : 0; + break; + default: + return -EINVAL; + } + + return 0; +} + +static struct bq24735_platform *bq24735_parse_dt_data(struct i2c_client *client) +{ + struct bq24735_platform *pdata; + struct device_node *np = client->dev.of_node; + u32 val; + int ret; + enum of_gpio_flags flags; + + pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) { + dev_err(&client->dev, + "Memory alloc for bq24735 pdata failed\n"); + return NULL; + } + + pdata->status_gpio = of_get_named_gpio_flags(np, "ti,ac-detect-gpios", + 0, &flags); + + if (flags & OF_GPIO_ACTIVE_LOW) + pdata->status_gpio_active_low = 1; + + ret = of_property_read_u32(np, "ti,charge-current", &val); + if (!ret) + pdata->charge_current = val; + + ret = of_property_read_u32(np, "ti,charge-voltage", &val); + if (!ret) + pdata->charge_voltage = val; + + ret = of_property_read_u32(np, "ti,input-current", &val); + if (!ret) + pdata->input_current = val; + + return pdata; +} + +static int bq24735_charger_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct bq24735 *charger; + struct power_supply *supply; + char *name; + + charger = devm_kzalloc(&client->dev, sizeof(*charger), GFP_KERNEL); + if (!charger) + return -ENOMEM; + + charger->pdata = client->dev.platform_data; + + if (IS_ENABLED(CONFIG_OF) && !charger->pdata && client->dev.of_node) + charger->pdata = bq24735_parse_dt_data(client); + + if (!charger->pdata) { + dev_err(&client->dev, "no platform data provided\n"); + return -EINVAL; + } + + name = (char *)charger->pdata->name; + if (!name) { + name = kasprintf(GFP_KERNEL, "bq24735@%s", + dev_name(&client->dev)); + if (!name) { + dev_err(&client->dev, "Failed to alloc device name\n"); + return -ENOMEM; + } + } + + charger->client = client; + + supply = &charger->charger; + + supply->name = name; + supply->type = POWER_SUPPLY_TYPE_MAINS; + supply->properties = bq24735_charger_properties; + supply->num_properties = ARRAY_SIZE(bq24735_charger_properties); + supply->get_property = bq24735_charger_get_property; + supply->supplied_to = charger->pdata->supplied_to; + supply->num_supplicants = charger->pdata->num_supplicants; + supply->of_node = client->dev.of_node; + + i2c_set_clientdata(client, charger); + + ret = bq24735_read_word(client, BQ24735_MANUFACTURER_ID); + if (ret < 0) { + dev_err(&client->dev, "Failed to read manufacturer id : %d\n", + ret); + goto err_free_name; + } else if (ret != 0x0040) { + dev_err(&client->dev, + "manufacturer id mismatch. 0x0040 != 0x%04x\n", ret); + ret = -ENODEV; + goto err_free_name; + } + + ret = bq24735_read_word(client, BQ24735_DEVICE_ID); + if (ret < 0) { + dev_err(&client->dev, "Failed to read device id : %d\n", ret); + goto err_free_name; + } else if (ret != 0x000B) { + dev_err(&client->dev, + "device id mismatch. 0x000b != 0x%04x\n", ret); + ret = -ENODEV; + goto err_free_name; + } + + if (gpio_is_valid(charger->pdata->status_gpio)) { + ret = devm_gpio_request(&client->dev, + charger->pdata->status_gpio, + name); + if (ret) { + dev_err(&client->dev, + "Failed GPIO request for GPIO %d: %d\n", + charger->pdata->status_gpio, ret); + } + + charger->pdata->status_gpio_valid = !ret; + } + + ret = bq24735_config_charger(charger); + if (ret < 0) { + dev_err(&client->dev, "failed in configuring charger"); + goto err_free_name; + } + + /* check for AC adapter presence */ + if (bq24735_charger_is_present(charger)) { + ret = bq24735_enable_charging(charger); + if (ret < 0) { + dev_err(&client->dev, "Failed to enable charging\n"); + goto err_free_name; + } + } + + ret = power_supply_register(&client->dev, supply); + if (ret < 0) { + dev_err(&client->dev, "Failed to register power supply: %d\n", + ret); + goto err_free_name; + } + + if (client->irq) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, bq24735_charger_isr, + IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING | + IRQF_ONESHOT, + supply->name, supply); + if (ret) { + dev_err(&client->dev, + "Unable to register IRQ %d err %d\n", + client->irq, ret); + goto err_unregister_supply; + } + } + + return 0; +err_unregister_supply: + power_supply_unregister(supply); +err_free_name: + if (name != charger->pdata->name) + kfree(name); + + return ret; +} + +static int bq24735_charger_remove(struct i2c_client *client) +{ + struct bq24735 *charger = i2c_get_clientdata(client); + + if (charger->client->irq) + devm_free_irq(&charger->client->dev, charger->client->irq, + &charger->charger); + + power_supply_unregister(&charger->charger); + + if (charger->charger.name != charger->pdata->name) + kfree(charger->charger.name); + + return 0; +} + +static const struct i2c_device_id bq24735_charger_id[] = { + { "bq24735-charger", 0 }, + {} +}; +MODULE_DEVICE_TABLE(i2c, bq24735_charger_id); + +static const struct of_device_id bq24735_match_ids[] = { + { .compatible = "ti,bq24735", }, + { /* end */ } +}; +MODULE_DEVICE_TABLE(of, bq24735_match_ids); + +static struct i2c_driver bq24735_charger_driver = { + .driver = { + .name = "bq24735-charger", + .owner = THIS_MODULE, + .of_match_table = bq24735_match_ids, + }, + .probe = bq24735_charger_probe, + .remove = bq24735_charger_remove, + .id_table = bq24735_charger_id, +}; + +module_i2c_driver(bq24735_charger_driver); + +MODULE_DESCRIPTION("bq24735 battery charging driver"); +MODULE_AUTHOR("Darbha Sriharsha <dsriharsha@nvidia.com>"); +MODULE_LICENSE("GPL v2"); |