[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/of.h>
#include <linux/of_gpio.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
struct gpio_charger_platform_data *gpio_charger_parse_dt(struct device *dev)
{
	struct device_node *np = dev->of_node;
	struct gpio_charger_platform_data *pdata;
	const char *chargetype;
	enum of_gpio_flags flags;
	int ret;

	if (!np)
		return ERR_PTR(-ENOENT);

	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);

	pdata->name = np->name;

	pdata->gpio = of_get_gpio_flags(np, 0, &flags);
	if (pdata->gpio < 0) {
		if (pdata->gpio != -EPROBE_DEFER)
			dev_err(dev, "could not get charger gpio\n");
		return ERR_PTR(pdata->gpio);
	}

	pdata->gpio_active_low = !!(flags & OF_GPIO_ACTIVE_LOW);

	pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
	ret = of_property_read_string(np, "charger-type", &chargetype);
	if (ret >= 0) {
		if (!strncmp("unknown", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
		else if (!strncmp("battery", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_BATTERY;
		else if (!strncmp("ups", chargetype, 3))
			pdata->type = POWER_SUPPLY_TYPE_UPS;
		else if (!strncmp("mains", chargetype, 5))
			pdata->type = POWER_SUPPLY_TYPE_MAINS;
		else if (!strncmp("usb-sdp", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_USB;
		else if (!strncmp("usb-dcp", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_USB_DCP;
		else if (!strncmp("usb-cdp", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_USB_CDP;
		else if (!strncmp("usb-aca", chargetype, 7))
			pdata->type = POWER_SUPPLY_TYPE_USB_ACA;
		else
			dev_warn(dev, "unknown charger type %s\n", chargetype);
	}

	return pdata;
}

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) {
		pdata = gpio_charger_parse_dt(&pdev->dev);
		if (IS_ERR(pdata)) {
			ret = PTR_ERR(pdata);
			if (ret != -EPROBE_DEFER)
				dev_err(&pdev->dev, "No platform data\n");
			return ret;
		}
	}

	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;
	charger->of_node = pdev->dev.of_node;

	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 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,
	.remove = gpio_charger_remove,
	.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");
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>
c8dd9cce HS	25	#include <linux/of.h>
c8dd9cce HS	26	#include <linux/of_gpio.h>
5070437c LPC	27
	28	#include <linux/power/gpio-charger.h>
	29
	30	struct gpio_charger {
	31	const struct gpio_charger_platform_data *pdata;
	32	unsigned int irq;
4ea81266	33	bool wakeup_enabled;
5070437c LPC	34
	35	struct power_supply charger;
	36	};
	37
	38	static irqreturn_t gpio_charger_irq(int irq, void *devid)
	39	{
	40	struct power_supply *charger = devid;
	41
	42	power_supply_changed(charger);
	43
	44	return IRQ_HANDLED;
	45	}
	46
	47	static inline struct gpio_charger psy_to_gpio_charger(struct power_supply psy)
	48	{
	49	return container_of(psy, struct gpio_charger, charger);
	50	}
	51
	52	static int gpio_charger_get_property(struct power_supply *psy,
	53	enum power_supply_property psp, union power_supply_propval *val)
	54	{
	55	struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy);
	56	const struct gpio_charger_platform_data *pdata = gpio_charger->pdata;
	57
	58	switch (psp) {
	59	case POWER_SUPPLY_PROP_ONLINE:
4d96fb1e	60	val->intval = !!gpio_get_value_cansleep(pdata->gpio);
5070437c LPC	61	val->intval ^= pdata->gpio_active_low;
	62	break;
	63	default:
	64	return -EINVAL;
	65	}
	66
	67	return 0;
	68	}
	69
	70	static enum power_supply_property gpio_charger_properties[] = {
	71	POWER_SUPPLY_PROP_ONLINE,
	72	};
	73
c8dd9cce HS	74	static
	75	struct gpio_charger_platform_data gpio_charger_parse_dt(struct device dev)
	76	{
	77	struct device_node *np = dev->of_node;
	78	struct gpio_charger_platform_data *pdata;
	79	const char *chargetype;
	80	enum of_gpio_flags flags;
	81	int ret;
	82
	83	if (!np)
	84	return ERR_PTR(-ENOENT);
	85
	86	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
	87	if (!pdata)
	88	return ERR_PTR(-ENOMEM);
	89
	90	pdata->name = np->name;
	91
	92	pdata->gpio = of_get_gpio_flags(np, 0, &flags);
	93	if (pdata->gpio < 0) {
	94	if (pdata->gpio != -EPROBE_DEFER)
	95	dev_err(dev, "could not get charger gpio\n");
	96	return ERR_PTR(pdata->gpio);
	97	}
	98
	99	pdata->gpio_active_low = !!(flags & OF_GPIO_ACTIVE_LOW);
	100
	101	pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
	102	ret = of_property_read_string(np, "charger-type", &chargetype);
	103	if (ret >= 0) {
	104	if (!strncmp("unknown", chargetype, 7))
	105	pdata->type = POWER_SUPPLY_TYPE_UNKNOWN;
	106	else if (!strncmp("battery", chargetype, 7))
	107	pdata->type = POWER_SUPPLY_TYPE_BATTERY;
	108	else if (!strncmp("ups", chargetype, 3))
	109	pdata->type = POWER_SUPPLY_TYPE_UPS;
	110	else if (!strncmp("mains", chargetype, 5))
	111	pdata->type = POWER_SUPPLY_TYPE_MAINS;
	112	else if (!strncmp("usb-sdp", chargetype, 7))
	113	pdata->type = POWER_SUPPLY_TYPE_USB;
	114	else if (!strncmp("usb-dcp", chargetype, 7))
	115	pdata->type = POWER_SUPPLY_TYPE_USB_DCP;
	116	else if (!strncmp("usb-cdp", chargetype, 7))
	117	pdata->type = POWER_SUPPLY_TYPE_USB_CDP;
	118	else if (!strncmp("usb-aca", chargetype, 7))
	119	pdata->type = POWER_SUPPLY_TYPE_USB_ACA;
	120	else
	121	dev_warn(dev, "unknown charger type %s\n", chargetype);
	122	}
	123
	124	return pdata;
	125	}
	126
c8afa640	127	static int gpio_charger_probe(struct platform_device *pdev)
5070437c LPC	128	{
	129	const struct gpio_charger_platform_data *pdata = pdev->dev.platform_data;
	130	struct gpio_charger *gpio_charger;
	131	struct power_supply *charger;
	132	int ret;
	133	int irq;
	134
	135	if (!pdata) {
c8dd9cce HS	136	pdata = gpio_charger_parse_dt(&pdev->dev);
	137	if (IS_ERR(pdata)) {
	138	ret = PTR_ERR(pdata);
	139	if (ret != -EPROBE_DEFER)
	140	dev_err(&pdev->dev, "No platform data\n");
	141	return ret;
	142	}
5070437c LPC	143	}
	144
	145	if (!gpio_is_valid(pdata->gpio)) {
	146	dev_err(&pdev->dev, "Invalid gpio pin\n");
	147	return -EINVAL;
	148	}
	149
b92ff855 JH	150	gpio_charger = devm_kzalloc(&pdev->dev, sizeof(*gpio_charger),
b92ff855 JH	151	GFP_KERNEL);
2e9ff5f5 LPC	152	if (!gpio_charger) {
	153	dev_err(&pdev->dev, "Failed to alloc driver structure\n");
	154	return -ENOMEM;
	155	}
5070437c LPC	156
	157	charger = &gpio_charger->charger;
	158
80577b8a	159	charger->name = pdata->name ? pdata->name : "gpio-charger";
5070437c LPC	160	charger->type = pdata->type;
	161	charger->properties = gpio_charger_properties;
	162	charger->num_properties = ARRAY_SIZE(gpio_charger_properties);
26eb3872	163	charger->get_property = gpio_charger_get_property;
5070437c LPC	164	charger->supplied_to = pdata->supplied_to;
5070437c LPC	165	charger->num_supplicants = pdata->num_supplicants;
c8dd9cce	166	charger->of_node = pdev->dev.of_node;
5070437c LPC	167
	168	ret = gpio_request(pdata->gpio, dev_name(&pdev->dev));
	169	if (ret) {
	170	dev_err(&pdev->dev, "Failed to request gpio pin: %d\n", ret);
	171	goto err_free;
	172	}
	173	ret = gpio_direction_input(pdata->gpio);
	174	if (ret) {
	175	dev_err(&pdev->dev, "Failed to set gpio to input: %d\n", ret);
	176	goto err_gpio_free;
	177	}
	178
26eb3872 LPC	179	gpio_charger->pdata = pdata;
	180
	181	ret = power_supply_register(&pdev->dev, charger);
	182	if (ret < 0) {
	183	dev_err(&pdev->dev, "Failed to register power supply: %d\n",
	184	ret);
	185	goto err_gpio_free;
	186	}
	187
5070437c LPC	188	irq = gpio_to_irq(pdata->gpio);
5070437c LPC	189	if (irq > 0) {
26eb3872	190	ret = request_any_context_irq(irq, gpio_charger_irq,
5070437c LPC	191	IRQF_TRIGGER_RISING \| IRQF_TRIGGER_FALLING,
5070437c LPC	192	dev_name(&pdev->dev), charger);
f8c63918	193	if (ret < 0)
5070437c LPC	194	dev_warn(&pdev->dev, "Failed to request irq: %d\n", ret);
	195	else
	196	gpio_charger->irq = irq;
	197	}
	198
5070437c LPC	199	platform_set_drvdata(pdev, gpio_charger);
5070437c LPC	200
4ea81266 DES	201	device_init_wakeup(&pdev->dev, 1);
4ea81266 DES	202
5070437c LPC	203	return 0;
5070437c LPC	204
5070437c LPC	205	err_gpio_free:
	206	gpio_free(pdata->gpio);
	207	err_free:
5070437c LPC	208	return ret;
	209	}
	210
415ec69f	211	static int gpio_charger_remove(struct platform_device *pdev)
5070437c LPC	212	{
	213	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
	214
5070437c LPC	215	if (gpio_charger->irq)
5070437c LPC	216	free_irq(gpio_charger->irq, &gpio_charger->charger);
26eb3872 LPC	217
	218	power_supply_unregister(&gpio_charger->charger);
	219
5070437c LPC	220	gpio_free(gpio_charger->pdata->gpio);
5070437c LPC	221
5070437c LPC	222	return 0;
	223	}
	224
f10513de	225	#ifdef CONFIG_PM_SLEEP
4ea81266 DES	226	static int gpio_charger_suspend(struct device *dev)
	227	{
	228	struct gpio_charger *gpio_charger = dev_get_drvdata(dev);
	229
	230	if (device_may_wakeup(dev))
	231	gpio_charger->wakeup_enabled =
	232	enable_irq_wake(gpio_charger->irq);
	233
	234	return 0;
	235	}
	236
f10513de BL	237	static int gpio_charger_resume(struct device *dev)
	238	{
	239	struct platform_device *pdev = to_platform_device(dev);
	240	struct gpio_charger *gpio_charger = platform_get_drvdata(pdev);
	241
4ea81266 DES	242	if (gpio_charger->wakeup_enabled)
4ea81266 DES	243	disable_irq_wake(gpio_charger->irq);
f10513de BL	244	power_supply_changed(&gpio_charger->charger);
	245
	246	return 0;
	247	}
	248	#endif
	249
4ea81266 DES	250	static SIMPLE_DEV_PM_OPS(gpio_charger_pm_ops,
4ea81266 DES	251	gpio_charger_suspend, gpio_charger_resume);
f10513de	252
c8dd9cce HS	253	static const struct of_device_id gpio_charger_match[] = {
	254	{ .compatible = "gpio-charger" },
	255	{ }
	256	};
	257	MODULE_DEVICE_TABLE(of, gpio_charger_match);
	258
5070437c LPC	259	static struct platform_driver gpio_charger_driver = {
5070437c LPC	260	.probe = gpio_charger_probe,
28ea73f4	261	.remove = gpio_charger_remove,
5070437c LPC	262	.driver = {
5070437c LPC	263	.name = "gpio-charger",
f10513de	264	.pm = &gpio_charger_pm_ops,
c8dd9cce	265	.of_match_table = gpio_charger_match,
5070437c LPC	266	},
	267	};
	268
300bac7f	269	module_platform_driver(gpio_charger_driver);
5070437c LPC	270
	271	MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
	272	MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO");
	273	MODULE_LICENSE("GPL");
	274	MODULE_ALIAS("platform:gpio-charger");