Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / drivers / power / gpio-charger.c

diff --git a/drivers/power/gpio-charger.c b/drivers/power/gpio-charger.c
new file mode 100644 (file)
index 0000000..25b88ac
--- /dev/null
+++ b/drivers/power/gpio-charger.c
@@ -0,0 +1,188 @@
+/*
+ *  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>
+#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/power/gpio-charger.h>
+
+struct gpio_charger {
+       const struct gpio_charger_platform_data *pdata;
+       unsigned int irq;
+
+       struct power_supply charger;
+};
+
+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 container_of(psy, struct gpio_charger, charger);
+}
+
+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);
+       const struct gpio_charger_platform_data *pdata = gpio_charger->pdata;
+
+       switch (psp) {
+       case POWER_SUPPLY_PROP_ONLINE:
+               val->intval = gpio_get_value(pdata->gpio);
+               val->intval ^= pdata->gpio_active_low;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static enum power_supply_property gpio_charger_properties[] = {
+       POWER_SUPPLY_PROP_ONLINE,
+};
+
+static int __devinit gpio_charger_probe(struct platform_device *pdev)
+{
+       const struct gpio_charger_platform_data *pdata = pdev->dev.platform_data;
+       struct gpio_charger *gpio_charger;
+       struct power_supply *charger;
+       int ret;
+       int irq;
+
+       if (!pdata) {
+               dev_err(&pdev->dev, "No platform data\n");
+               return -EINVAL;
+       }
+
+       if (!gpio_is_valid(pdata->gpio)) {
+               dev_err(&pdev->dev, "Invalid gpio pin\n");
+               return -EINVAL;
+       }
+
+       gpio_charger = kzalloc(sizeof(*gpio_charger), GFP_KERNEL);
+       if (!gpio_charger) {
+               dev_err(&pdev->dev, "Failed to alloc driver structure\n");
+               return -ENOMEM;
+       }
+
+       charger = &gpio_charger->charger;
+
+       charger->name = pdata->name ? pdata->name : "gpio-charger";
+       charger->type = pdata->type;
+       charger->properties = gpio_charger_properties;
+       charger->num_properties = ARRAY_SIZE(gpio_charger_properties);
+       charger->get_property = gpio_charger_get_property;
+       charger->supplied_to = pdata->supplied_to;
+       charger->num_supplicants = pdata->num_supplicants;
+
+       ret = gpio_request(pdata->gpio, dev_name(&pdev->dev));
+       if (ret) {
+               dev_err(&pdev->dev, "Failed to request gpio pin: %d\n", ret);
+               goto err_free;
+       }
+       ret = gpio_direction_input(pdata->gpio);
+       if (ret) {
+               dev_err(&pdev->dev, "Failed to set gpio to input: %d\n", ret);
+               goto err_gpio_free;
+       }
+
+       gpio_charger->pdata = pdata;
+
+       ret = power_supply_register(&pdev->dev, charger);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "Failed to register power supply: %d\n",
+                       ret);
+               goto err_gpio_free;
+       }
+
+       irq = gpio_to_irq(pdata->gpio);
+       if (irq > 0) {
+               ret = request_any_context_irq(irq, gpio_charger_irq,
+                               IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+                               dev_name(&pdev->dev), charger);
+               if (ret)
+                       dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
+               else
+                       gpio_charger->irq = irq;
+       }
+
+       platform_set_drvdata(pdev, gpio_charger);
+
+       return 0;
+
+err_gpio_free:
+       gpio_free(pdata->gpio);
+err_free:
+       kfree(gpio_charger);
+       return ret;
+}
+
+static int __devexit gpio_charger_remove(struct platform_device *pdev)
+{
+       struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
+
+       if (gpio_charger->irq)
+               free_irq(gpio_charger->irq, &gpio_charger->charger);
+
+       power_supply_unregister(&gpio_charger->charger);
+
+       gpio_free(gpio_charger->pdata->gpio);
+
+       platform_set_drvdata(pdev, NULL);
+       kfree(gpio_charger);
+
+       return 0;
+}
+
+static struct platform_driver gpio_charger_driver = {
+       .probe = gpio_charger_probe,
+       .remove = __devexit_p(gpio_charger_remove),
+       .driver = {
+               .name = "gpio-charger",
+               .owner = THIS_MODULE,
+       },
+};
+
+static int __init gpio_charger_init(void)
+{
+       return platform_driver_register(&gpio_charger_driver);
+}
+module_init(gpio_charger_init);
+
+static void __exit gpio_charger_exit(void)
+{
+       platform_driver_unregister(&gpio_charger_driver);
+}
+module_exit(gpio_charger_exit);
+
+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");