| /* |
| * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de> |
| * Driver for chargers which report their online status through a GPIO pin |
| * |
| * 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. |
| * |
| * 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., |
| * 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/gpio.h> /* For legacy platform data */ |
| #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> |
| #include <linux/gpio/consumer.h> |
| |
| #include <linux/power/gpio-charger.h> |
| |
| struct gpio_charger { |
| unsigned int irq; |
| bool wakeup_enabled; |
| |
| struct power_supply *charger; |
| struct power_supply_desc charger_desc; |
| struct gpio_desc *gpiod; |
| }; |
| |
| static irqreturn_t gpio_charger_irq(int irq, void *devid) |
| { |
| struct power_supply *charger = devid; |
| |
| power_supply_changed(charger); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static inline struct gpio_charger *psy_to_gpio_charger(struct power_supply *psy) |
| { |
| return power_supply_get_drvdata(psy); |
| } |
| |
| static int gpio_charger_get_property(struct power_supply *psy, |
| enum power_supply_property psp, union power_supply_propval *val) |
| { |
| struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy); |
| |
| switch (psp) { |
| case POWER_SUPPLY_PROP_ONLINE: |
| val->intval = gpiod_get_value_cansleep(gpio_charger->gpiod); |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static enum power_supply_type gpio_charger_get_type(struct device *dev) |
| { |
| const char *chargetype; |
| |
| if (!device_property_read_string(dev, "charger-type", &chargetype)) { |
| if (!strcmp("unknown", chargetype)) |
| return POWER_SUPPLY_TYPE_UNKNOWN; |
| if (!strcmp("battery", chargetype)) |
| return POWER_SUPPLY_TYPE_BATTERY; |
| if (!strcmp("ups", chargetype)) |
| return POWER_SUPPLY_TYPE_UPS; |
| if (!strcmp("mains", chargetype)) |
| return POWER_SUPPLY_TYPE_MAINS; |
| if (!strcmp("usb-sdp", chargetype)) |
| return POWER_SUPPLY_TYPE_USB; |
| if (!strcmp("usb-dcp", chargetype)) |
| return POWER_SUPPLY_TYPE_USB_DCP; |
| if (!strcmp("usb-cdp", chargetype)) |
| return POWER_SUPPLY_TYPE_USB_CDP; |
| if (!strcmp("usb-aca", chargetype)) |
| return POWER_SUPPLY_TYPE_USB_ACA; |
| } |
| dev_warn(dev, "unknown charger type %s\n", chargetype); |
| |
| return POWER_SUPPLY_TYPE_UNKNOWN; |
| } |
| |
| static enum power_supply_property gpio_charger_properties[] = { |
| POWER_SUPPLY_PROP_ONLINE, |
| }; |
| |
| static int gpio_charger_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| const struct gpio_charger_platform_data *pdata = dev->platform_data; |
| struct power_supply_config psy_cfg = {}; |
| struct gpio_charger *gpio_charger; |
| struct power_supply_desc *charger_desc; |
| unsigned long flags; |
| int irq, ret; |
| |
| if (!pdata && !dev->of_node) { |
| dev_err(dev, "No platform data\n"); |
| return -ENOENT; |
| } |
| |
| gpio_charger = devm_kzalloc(dev, sizeof(*gpio_charger), GFP_KERNEL); |
| if (!gpio_charger) |
| return -ENOMEM; |
| |
| /* |
| * This will fetch a GPIO descriptor from device tree, ACPI or |
| * boardfile descriptor tables. It's good to try this first. |
| */ |
| gpio_charger->gpiod = devm_gpiod_get(dev, NULL, GPIOD_IN); |
| |
| /* |
| * If this fails and we're not using device tree, try the |
| * legacy platform data method. |
| */ |
| if (IS_ERR(gpio_charger->gpiod) && !dev->of_node) { |
| /* Non-DT: use legacy GPIO numbers */ |
| if (!gpio_is_valid(pdata->gpio)) { |
| dev_err(dev, "Invalid gpio pin in pdata\n"); |
| return -EINVAL; |
| } |
| flags = GPIOF_IN; |
| if (pdata->gpio_active_low) |
| flags |= GPIOF_ACTIVE_LOW; |
| ret = devm_gpio_request_one(dev, pdata->gpio, flags, |
| dev_name(dev)); |
| if (ret) { |
| dev_err(dev, "Failed to request gpio pin: %d\n", ret); |
| return ret; |
| } |
| /* Then convert this to gpiod for now */ |
| gpio_charger->gpiod = gpio_to_desc(pdata->gpio); |
| } else if (IS_ERR(gpio_charger->gpiod)) { |
| /* Just try again if this happens */ |
| if (PTR_ERR(gpio_charger->gpiod) == -EPROBE_DEFER) |
| return -EPROBE_DEFER; |
| dev_err(dev, "error getting GPIO descriptor\n"); |
| return PTR_ERR(gpio_charger->gpiod); |
| } |
| |
| charger_desc = &gpio_charger->charger_desc; |
| charger_desc->properties = gpio_charger_properties; |
| charger_desc->num_properties = ARRAY_SIZE(gpio_charger_properties); |
| charger_desc->get_property = gpio_charger_get_property; |
| |
| psy_cfg.of_node = dev->of_node; |
| psy_cfg.drv_data = gpio_charger; |
| |
| if (pdata) { |
| charger_desc->name = pdata->name; |
| charger_desc->type = pdata->type; |
| psy_cfg.supplied_to = pdata->supplied_to; |
| psy_cfg.num_supplicants = pdata->num_supplicants; |
| } else { |
| charger_desc->name = dev->of_node->name; |
| charger_desc->type = gpio_charger_get_type(dev); |
| } |
| |
| if (!charger_desc->name) |
| charger_desc->name = pdev->name; |
| |
| gpio_charger->charger = devm_power_supply_register(dev, charger_desc, |
| &psy_cfg); |
| if (IS_ERR(gpio_charger->charger)) { |
| ret = PTR_ERR(gpio_charger->charger); |
| dev_err(dev, "Failed to register power supply: %d\n", ret); |
| return ret; |
| } |
| |
| irq = gpiod_to_irq(gpio_charger->gpiod); |
| if (irq > 0) { |
| ret = devm_request_any_context_irq(dev, irq, gpio_charger_irq, |
| IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, |
| dev_name(dev), gpio_charger->charger); |
| if (ret < 0) |
| dev_warn(dev, "Failed to request irq: %d\n", ret); |
| else |
| gpio_charger->irq = irq; |
| } |
| |
| platform_set_drvdata(pdev, gpio_charger); |
| |
| device_init_wakeup(dev, 1); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int gpio_charger_suspend(struct device *dev) |
| { |
| struct gpio_charger *gpio_charger = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev)) |
| gpio_charger->wakeup_enabled = |
| !enable_irq_wake(gpio_charger->irq); |
| |
| return 0; |
| } |
| |
| static int gpio_charger_resume(struct device *dev) |
| { |
| struct gpio_charger *gpio_charger = dev_get_drvdata(dev); |
| |
| if (device_may_wakeup(dev) && gpio_charger->wakeup_enabled) |
| disable_irq_wake(gpio_charger->irq); |
| power_supply_changed(gpio_charger->charger); |
| |
| return 0; |
| } |
| #endif |
| |
| static SIMPLE_DEV_PM_OPS(gpio_charger_pm_ops, |
| gpio_charger_suspend, gpio_charger_resume); |
| |
| static const struct of_device_id gpio_charger_match[] = { |
| { .compatible = "gpio-charger" }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, gpio_charger_match); |
| |
| static struct platform_driver gpio_charger_driver = { |
| .probe = gpio_charger_probe, |
| .driver = { |
| .name = "gpio-charger", |
| .pm = &gpio_charger_pm_ops, |
| .of_match_table = gpio_charger_match, |
| }, |
| }; |
| |
| module_platform_driver(gpio_charger_driver); |
| |
| MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); |
| MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:gpio-charger"); |