2 * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
3 * Driver for chargers which report their online status through a GPIO pin
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
10 * You should have received a copy of the GNU General Public License along
11 * with this program; if not, write to the Free Software Foundation, Inc.,
12 * 675 Mass Ave, Cambridge, MA 02139, USA.
16 #include <linux/device.h>
17 #include <linux/gpio.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/power_supply.h>
24 #include <linux/slab.h>
26 #include <linux/power/gpio-charger.h>
29 const struct gpio_charger_platform_data *pdata;
32 struct power_supply charger;
35 static irqreturn_t gpio_charger_irq(int irq, void *devid)
37 struct power_supply *charger = devid;
39 power_supply_changed(charger);
44 static inline struct gpio_charger *psy_to_gpio_charger(struct power_supply *psy)
46 return container_of(psy, struct gpio_charger, charger);
49 static int gpio_charger_get_property(struct power_supply *psy,
50 enum power_supply_property psp, union power_supply_propval *val)
52 struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy);
53 const struct gpio_charger_platform_data *pdata = gpio_charger->pdata;
56 case POWER_SUPPLY_PROP_ONLINE:
57 val->intval = gpio_get_value(pdata->gpio);
58 val->intval ^= pdata->gpio_active_low;
67 static enum power_supply_property gpio_charger_properties[] = {
68 POWER_SUPPLY_PROP_ONLINE,
71 static int __devinit gpio_charger_probe(struct platform_device *pdev)
73 const struct gpio_charger_platform_data *pdata = pdev->dev.platform_data;
74 struct gpio_charger *gpio_charger;
75 struct power_supply *charger;
80 dev_err(&pdev->dev, "No platform data\n");
84 if (!gpio_is_valid(pdata->gpio)) {
85 dev_err(&pdev->dev, "Invalid gpio pin\n");
89 gpio_charger = kzalloc(sizeof(*gpio_charger), GFP_KERNEL);
91 charger = &gpio_charger->charger;
93 charger->name = pdata->name;
94 charger->type = pdata->type;
95 charger->properties = gpio_charger_properties;
96 charger->num_properties = ARRAY_SIZE(gpio_charger_properties);
97 charger->get_property = gpio_charger_get_property;
98 charger->supplied_to = pdata->supplied_to;
99 charger->num_supplicants = pdata->num_supplicants;
101 ret = gpio_request(pdata->gpio, dev_name(&pdev->dev));
103 dev_err(&pdev->dev, "Failed to request gpio pin: %d\n", ret);
106 ret = gpio_direction_input(pdata->gpio);
108 dev_err(&pdev->dev, "Failed to set gpio to input: %d\n", ret);
112 irq = gpio_to_irq(pdata->gpio);
114 ret = request_irq(irq, gpio_charger_irq,
115 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
116 dev_name(&pdev->dev), charger);
118 dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
120 gpio_charger->irq = irq;
123 gpio_charger->pdata = pdata;
125 ret = power_supply_register(&pdev->dev, charger);
127 dev_err(&pdev->dev, "Failed to register power supply: %d\n", ret);
131 platform_set_drvdata(pdev, gpio_charger);
136 if (gpio_charger->irq)
137 free_irq(gpio_charger->irq, charger);
139 gpio_free(pdata->gpio);
145 static int __devexit gpio_charger_remove(struct platform_device *pdev)
147 struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
149 power_supply_unregister(&gpio_charger->charger);
151 if (gpio_charger->irq)
152 free_irq(gpio_charger->irq, &gpio_charger->charger);
153 gpio_free(gpio_charger->pdata->gpio);
155 platform_set_drvdata(pdev, NULL);
161 static struct platform_driver gpio_charger_driver = {
162 .probe = gpio_charger_probe,
163 .remove = __devexit_p(gpio_charger_remove),
165 .name = "gpio-charger",
166 .owner = THIS_MODULE,
170 static int __init gpio_charger_init(void)
172 return platform_driver_register(&gpio_charger_driver);
174 module_init(gpio_charger_init);
176 static void __exit gpio_charger_exit(void)
178 platform_driver_unregister(&gpio_charger_driver);
180 module_exit(gpio_charger_exit);
182 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
183 MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO");
184 MODULE_LICENSE("GPL");
185 MODULE_ALIAS("platform:gpio-charger");