|  | /* | 
|  | * 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 power_supply_desc	charger_desc; | 
|  | struct i2c_client		*client; | 
|  | struct bq24735_platform		*pdata; | 
|  | }; | 
|  |  | 
|  | static inline struct bq24735 *to_bq24735(struct power_supply *psy) | 
|  | { | 
|  | return power_supply_get_drvdata(psy); | 
|  | } | 
|  |  | 
|  | 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 = to_bq24735(psy); | 
|  |  | 
|  | 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_desc *supply_desc; | 
|  | struct power_supply_config psy_cfg = {}; | 
|  | 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_desc = &charger->charger_desc; | 
|  |  | 
|  | supply_desc->name = name; | 
|  | supply_desc->type = POWER_SUPPLY_TYPE_MAINS; | 
|  | supply_desc->properties = bq24735_charger_properties; | 
|  | supply_desc->num_properties = ARRAY_SIZE(bq24735_charger_properties); | 
|  | supply_desc->get_property = bq24735_charger_get_property; | 
|  |  | 
|  | psy_cfg.supplied_to = charger->pdata->supplied_to; | 
|  | psy_cfg.num_supplicants = charger->pdata->num_supplicants; | 
|  | psy_cfg.of_node = client->dev.of_node; | 
|  | psy_cfg.drv_data = charger; | 
|  |  | 
|  | 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; | 
|  | } | 
|  | } | 
|  |  | 
|  | charger->charger = power_supply_register(&client->dev, supply_desc, | 
|  | &psy_cfg); | 
|  | if (IS_ERR(charger->charger)) { | 
|  | ret = PTR_ERR(charger->charger); | 
|  | 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_desc->name, | 
|  | charger->charger); | 
|  | 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(charger->charger); | 
|  | 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_desc.name != charger->pdata->name) | 
|  | kfree(charger->charger_desc.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"); |