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authorLars-Peter Clausen <lars@metafoo.de>2010-10-21 17:55:01 +0200
committerAnton Vorontsov <cbouatmailru@gmail.com>2010-11-18 16:56:17 +0300
commit5070437cd99511f69ae561f2ab417142a47a85ec (patch)
tree379dd2ab427ff33c09bee57f9d89726071b64137 /drivers/power/gpio-charger.c
parent8ec98fe0b4ffdedce4c1caa9fb3d550f52ad1c6b (diff)
power_supply: Add gpio charger driver
This patch adds a simple driver for chargers indicating their online status through a GPIO pin. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Diffstat (limited to 'drivers/power/gpio-charger.c')
-rw-r--r--drivers/power/gpio-charger.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/power/gpio-charger.c b/drivers/power/gpio-charger.c
new file mode 100644
index 000000000000..fccbe99b619c
--- /dev/null
+++ b/drivers/power/gpio-charger.c
@@ -0,0 +1,185 @@
+/*
+ * 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);
+
+ charger = &gpio_charger->charger;
+
+ charger->name = pdata->name;
+ 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;
+ }
+
+ irq = gpio_to_irq(pdata->gpio);
+ if (irq > 0) {
+ ret = request_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;
+ }
+
+ 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_irq_free;
+ }
+
+ platform_set_drvdata(pdev, gpio_charger);
+
+ return 0;
+
+err_irq_free:
+ if (gpio_charger->irq)
+ free_irq(gpio_charger->irq, charger);
+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);
+
+ power_supply_unregister(&gpio_charger->charger);
+
+ if (gpio_charger->irq)
+ free_irq(gpio_charger->irq, &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");