[deliverable/linux.git] / drivers / power / gpio-charger.c

/*
 *  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;
	bool wakeup_enabled;

	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_cansleep(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 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 = devm_kzalloc(&pdev->dev, 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 < 0)
			dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
		else
			gpio_charger->irq = irq;
	}

	platform_set_drvdata(pdev, gpio_charger);

	device_init_wakeup(&pdev->dev, 1);

	return 0;

err_gpio_free:
	gpio_free(pdata->gpio);
err_free:
	return ret;
}

static int 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);

	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 platform_device *pdev = to_platform_device(dev);
	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);

	if (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 struct platform_driver gpio_charger_driver = {
	.probe = gpio_charger_probe,
	.remove = gpio_charger_remove,
	.driver = {
		.name = "gpio-charger",
		.owner = THIS_MODULE,
		.pm = &gpio_charger_pm_ops,
	},
};

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");
Commit	Line	Data
5070437c LPC	1	/*
	2	* Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
	3	* Driver for chargers which report their online status through a GPIO pin
	4	*
	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.
	9	*
	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.
	13	*
	14	*/
	15
	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>
	25
	26	#include <linux/power/gpio-charger.h>
	27
	28	struct gpio_charger {
	29	const struct gpio_charger_platform_data *pdata;
	30	unsigned int irq;
4ea81266	31	bool wakeup_enabled;
5070437c LPC	32
	33	struct power_supply charger;
	34	};
	35
	36	static irqreturn_t gpio_charger_irq(int irq, void *devid)
	37	{
	38	struct power_supply *charger = devid;
	39
	40	power_supply_changed(charger);
	41
	42	return IRQ_HANDLED;
	43	}
	44
	45	static inline struct gpio_charger psy_to_gpio_charger(struct power_supply psy)
	46	{
	47	return container_of(psy, struct gpio_charger, charger);
	48	}
	49
	50	static int gpio_charger_get_property(struct power_supply *psy,
	51	enum power_supply_property psp, union power_supply_propval *val)
	52	{
	53	struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy);
	54	const struct gpio_charger_platform_data *pdata = gpio_charger->pdata;
	55
	56	switch (psp) {
	57	case POWER_SUPPLY_PROP_ONLINE:
ecb7a8eb	58	val->intval = gpio_get_value_cansleep(pdata->gpio);
5070437c LPC	59	val->intval ^= pdata->gpio_active_low;
	60	break;
	61	default:
	62	return -EINVAL;
	63	}
	64
	65	return 0;
	66	}
	67
	68	static enum power_supply_property gpio_charger_properties[] = {
	69	POWER_SUPPLY_PROP_ONLINE,
	70	};
	71
c8afa640	72	static int gpio_charger_probe(struct platform_device *pdev)
5070437c LPC	73	{
	74	const struct gpio_charger_platform_data *pdata = pdev->dev.platform_data;
	75	struct gpio_charger *gpio_charger;
	76	struct power_supply *charger;
	77	int ret;
	78	int irq;
	79
	80	if (!pdata) {
	81	dev_err(&pdev->dev, "No platform data\n");
	82	return -EINVAL;
	83	}
	84
	85	if (!gpio_is_valid(pdata->gpio)) {
	86	dev_err(&pdev->dev, "Invalid gpio pin\n");
	87	return -EINVAL;
	88	}
	89
b92ff855 JH	90	gpio_charger = devm_kzalloc(&pdev->dev, sizeof(*gpio_charger),
b92ff855 JH	91	GFP_KERNEL);
2e9ff5f5 LPC	92	if (!gpio_charger) {
	93	dev_err(&pdev->dev, "Failed to alloc driver structure\n");
	94	return -ENOMEM;
	95	}
5070437c LPC	96
	97	charger = &gpio_charger->charger;
	98
80577b8a	99	charger->name = pdata->name ? pdata->name : "gpio-charger";
5070437c LPC	100	charger->type = pdata->type;
	101	charger->properties = gpio_charger_properties;
	102	charger->num_properties = ARRAY_SIZE(gpio_charger_properties);
26eb3872	103	charger->get_property = gpio_charger_get_property;
5070437c LPC	104	charger->supplied_to = pdata->supplied_to;
	105	charger->num_supplicants = pdata->num_supplicants;
	106
	107	ret = gpio_request(pdata->gpio, dev_name(&pdev->dev));
	108	if (ret) {
	109	dev_err(&pdev->dev, "Failed to request gpio pin: %d\n", ret);
	110	goto err_free;
	111	}
	112	ret = gpio_direction_input(pdata->gpio);
	113	if (ret) {
	114	dev_err(&pdev->dev, "Failed to set gpio to input: %d\n", ret);
	115	goto err_gpio_free;
	116	}
	117
26eb3872 LPC	118	gpio_charger->pdata = pdata;
	119
	120	ret = power_supply_register(&pdev->dev, charger);
	121	if (ret < 0) {
	122	dev_err(&pdev->dev, "Failed to register power supply: %d\n",
	123	ret);
	124	goto err_gpio_free;
	125	}
	126
5070437c LPC	127	irq = gpio_to_irq(pdata->gpio);
5070437c LPC	128	if (irq > 0) {
26eb3872	129	ret = request_any_context_irq(irq, gpio_charger_irq,
5070437c LPC	130	IRQF_TRIGGER_RISING \| IRQF_TRIGGER_FALLING,
5070437c LPC	131	dev_name(&pdev->dev), charger);
f8c63918	132	if (ret < 0)
5070437c LPC	133	dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
	134	else
	135	gpio_charger->irq = irq;
	136	}
	137
5070437c LPC	138	platform_set_drvdata(pdev, gpio_charger);
5070437c LPC	139
4ea81266 DES	140	device_init_wakeup(&pdev->dev, 1);
4ea81266 DES	141
5070437c LPC	142	return 0;
5070437c LPC	143
5070437c LPC	144	err_gpio_free:
	145	gpio_free(pdata->gpio);
	146	err_free:
5070437c LPC	147	return ret;
	148	}
	149
415ec69f	150	static int gpio_charger_remove(struct platform_device *pdev)
5070437c LPC	151	{
	152	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
	153
5070437c LPC	154	if (gpio_charger->irq)
5070437c LPC	155	free_irq(gpio_charger->irq, &gpio_charger->charger);
26eb3872 LPC	156
	157	power_supply_unregister(&gpio_charger->charger);
	158
5070437c LPC	159	gpio_free(gpio_charger->pdata->gpio);
5070437c LPC	160
5070437c LPC	161	return 0;
	162	}
	163
f10513de	164	#ifdef CONFIG_PM_SLEEP
4ea81266 DES	165	static int gpio_charger_suspend(struct device *dev)
	166	{
	167	struct gpio_charger *gpio_charger = dev_get_drvdata(dev);
	168
	169	if (device_may_wakeup(dev))
	170	gpio_charger->wakeup_enabled =
	171	enable_irq_wake(gpio_charger->irq);
	172
	173	return 0;
	174	}
	175
f10513de BL	176	static int gpio_charger_resume(struct device *dev)
	177	{
	178	struct platform_device *pdev = to_platform_device(dev);
	179	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
	180
4ea81266 DES	181	if (gpio_charger->wakeup_enabled)
4ea81266 DES	182	disable_irq_wake(gpio_charger->irq);
f10513de BL	183	power_supply_changed(&gpio_charger->charger);
	184
	185	return 0;
	186	}
	187	#endif
	188
4ea81266 DES	189	static SIMPLE_DEV_PM_OPS(gpio_charger_pm_ops,
4ea81266 DES	190	gpio_charger_suspend, gpio_charger_resume);
f10513de	191
5070437c LPC	192	static struct platform_driver gpio_charger_driver = {
5070437c LPC	193	.probe = gpio_charger_probe,
28ea73f4	194	.remove = gpio_charger_remove,
5070437c LPC	195	.driver = {
	196	.name = "gpio-charger",
	197	.owner = THIS_MODULE,
f10513de	198	.pm = &gpio_charger_pm_ops,
5070437c LPC	199	},
	200	};
	201
300bac7f	202	module_platform_driver(gpio_charger_driver);
5070437c LPC	203
	204	MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
	205	MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO");
	206	MODULE_LICENSE("GPL");
	207	MODULE_ALIAS("platform:gpio-charger");