diff options
Diffstat (limited to 'drivers/power/supply/ltc3651-charger.c')
| -rw-r--r-- | drivers/power/supply/ltc3651-charger.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/drivers/power/supply/ltc3651-charger.c b/drivers/power/supply/ltc3651-charger.c new file mode 100644 index 000000000..eea63ff21 --- /dev/null +++ b/drivers/power/supply/ltc3651-charger.c @@ -0,0 +1,210 @@ +/* + * Copyright (C) 2017, Topic Embedded Products + * Driver for LTC3651 charger IC. + * + * 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. + */ + +#include <linux/device.h> +#include <linux/gpio/consumer.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power_supply.h> +#include <linux/slab.h> +#include <linux/of.h> + +struct ltc3651_charger { + struct power_supply *charger; + struct power_supply_desc charger_desc; + struct gpio_desc *acpr_gpio; + struct gpio_desc *fault_gpio; + struct gpio_desc *chrg_gpio; +}; + +static irqreturn_t ltc3651_charger_irq(int irq, void *devid) +{ + struct power_supply *charger = devid; + + power_supply_changed(charger); + + return IRQ_HANDLED; +} + +static inline struct ltc3651_charger *psy_to_ltc3651_charger( + struct power_supply *psy) +{ + return power_supply_get_drvdata(psy); +} + +static int ltc3651_charger_get_property(struct power_supply *psy, + enum power_supply_property psp, union power_supply_propval *val) +{ + struct ltc3651_charger *ltc3651_charger = psy_to_ltc3651_charger(psy); + + switch (psp) { + case POWER_SUPPLY_PROP_STATUS: + if (!ltc3651_charger->chrg_gpio) { + val->intval = POWER_SUPPLY_STATUS_UNKNOWN; + break; + } + if (gpiod_get_value(ltc3651_charger->chrg_gpio)) + val->intval = POWER_SUPPLY_STATUS_CHARGING; + else + val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; + break; + case POWER_SUPPLY_PROP_ONLINE: + val->intval = gpiod_get_value(ltc3651_charger->acpr_gpio); + break; + case POWER_SUPPLY_PROP_HEALTH: + if (!ltc3651_charger->fault_gpio) { + val->intval = POWER_SUPPLY_HEALTH_UNKNOWN; + break; + } + if (!gpiod_get_value(ltc3651_charger->fault_gpio)) { + val->intval = POWER_SUPPLY_HEALTH_GOOD; + break; + } + /* + * If the fault pin is active, the chrg pin explains the type + * of failure. + */ + if (!ltc3651_charger->chrg_gpio) { + val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE; + break; + } + val->intval = gpiod_get_value(ltc3651_charger->chrg_gpio) ? + POWER_SUPPLY_HEALTH_OVERHEAT : + POWER_SUPPLY_HEALTH_DEAD; + break; + default: + return -EINVAL; + } + + return 0; +} + +static enum power_supply_property ltc3651_charger_properties[] = { + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_HEALTH, +}; + +static int ltc3651_charger_probe(struct platform_device *pdev) +{ + struct power_supply_config psy_cfg = {}; + struct ltc3651_charger *ltc3651_charger; + struct power_supply_desc *charger_desc; + int ret; + + ltc3651_charger = devm_kzalloc(&pdev->dev, sizeof(*ltc3651_charger), + GFP_KERNEL); + if (!ltc3651_charger) + return -ENOMEM; + + ltc3651_charger->acpr_gpio = devm_gpiod_get(&pdev->dev, + "lltc,acpr", GPIOD_IN); + if (IS_ERR(ltc3651_charger->acpr_gpio)) { + ret = PTR_ERR(ltc3651_charger->acpr_gpio); + dev_err(&pdev->dev, "Failed to acquire acpr GPIO: %d\n", ret); + return ret; + } + ltc3651_charger->fault_gpio = devm_gpiod_get_optional(&pdev->dev, + "lltc,fault", GPIOD_IN); + if (IS_ERR(ltc3651_charger->fault_gpio)) { + ret = PTR_ERR(ltc3651_charger->fault_gpio); + dev_err(&pdev->dev, "Failed to acquire fault GPIO: %d\n", ret); + return ret; + } + ltc3651_charger->chrg_gpio = devm_gpiod_get_optional(&pdev->dev, + "lltc,chrg", GPIOD_IN); + if (IS_ERR(ltc3651_charger->chrg_gpio)) { + ret = PTR_ERR(ltc3651_charger->chrg_gpio); + dev_err(&pdev->dev, "Failed to acquire chrg GPIO: %d\n", ret); + return ret; + } + + charger_desc = <c3651_charger->charger_desc; + charger_desc->name = pdev->dev.of_node->name; + charger_desc->type = POWER_SUPPLY_TYPE_MAINS; + charger_desc->properties = ltc3651_charger_properties; + charger_desc->num_properties = ARRAY_SIZE(ltc3651_charger_properties); + charger_desc->get_property = ltc3651_charger_get_property; + psy_cfg.of_node = pdev->dev.of_node; + psy_cfg.drv_data = ltc3651_charger; + + ltc3651_charger->charger = devm_power_supply_register(&pdev->dev, + charger_desc, &psy_cfg); + if (IS_ERR(ltc3651_charger->charger)) { + ret = PTR_ERR(ltc3651_charger->charger); + dev_err(&pdev->dev, "Failed to register power supply: %d\n", + ret); + return ret; + } + + /* + * Acquire IRQs for the GPIO pins if possible. If the system does not + * support IRQs on these pins, userspace will have to poll the sysfs + * files manually. + */ + if (ltc3651_charger->acpr_gpio) { + ret = gpiod_to_irq(ltc3651_charger->acpr_gpio); + if (ret >= 0) + ret = devm_request_any_context_irq(&pdev->dev, ret, + ltc3651_charger_irq, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, + dev_name(&pdev->dev), ltc3651_charger->charger); + if (ret < 0) + dev_warn(&pdev->dev, "Failed to request acpr irq\n"); + } + if (ltc3651_charger->fault_gpio) { + ret = gpiod_to_irq(ltc3651_charger->fault_gpio); + if (ret >= 0) + ret = devm_request_any_context_irq(&pdev->dev, ret, + ltc3651_charger_irq, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, + dev_name(&pdev->dev), ltc3651_charger->charger); + if (ret < 0) + dev_warn(&pdev->dev, "Failed to request fault irq\n"); + } + if (ltc3651_charger->chrg_gpio) { + ret = gpiod_to_irq(ltc3651_charger->chrg_gpio); + if (ret >= 0) + ret = devm_request_any_context_irq(&pdev->dev, ret, + ltc3651_charger_irq, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, + dev_name(&pdev->dev), ltc3651_charger->charger); + if (ret < 0) + dev_warn(&pdev->dev, "Failed to request chrg irq\n"); + } + + platform_set_drvdata(pdev, ltc3651_charger); + + return 0; +} + +static const struct of_device_id ltc3651_charger_match[] = { + { .compatible = "lltc,ltc3651-charger" }, + { } +}; +MODULE_DEVICE_TABLE(of, ltc3651_charger_match); + +static struct platform_driver ltc3651_charger_driver = { + .probe = ltc3651_charger_probe, + .driver = { + .name = "ltc3651-charger", + .of_match_table = ltc3651_charger_match, + }, +}; + +module_platform_driver(ltc3651_charger_driver); + +MODULE_AUTHOR("Mike Looijmans <mike.looijmans@topic.nl>"); +MODULE_DESCRIPTION("Driver for LTC3651 charger"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ltc3651-charger"); |