drivers/power/supply/gpio-charger.c - linux - Git at Google

 /*
  *  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> /* For legacy platform data */
 #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/gpio/consumer.h>

 #include <linux/power/gpio-charger.h>

 struct gpio_charger {
 	unsigned int irq;
 	unsigned int charge_status_irq;
 	bool wakeup_enabled;

 	struct power_supply *charger;
 	struct power_supply_desc charger_desc;
 	struct gpio_desc *gpiod;
 	struct gpio_desc *charge_status;
 };

 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 power_supply_get_drvdata(psy);
 }

 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);

 	switch (psp) {
 	case POWER_SUPPLY_PROP_ONLINE:
 		val->intval = gpiod_get_value_cansleep(gpio_charger->gpiod);
 		break;
 	case POWER_SUPPLY_PROP_STATUS:
 		if (gpiod_get_value_cansleep(gpio_charger->charge_status))
 			val->intval = POWER_SUPPLY_STATUS_CHARGING;
 		else
 			val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
 		break;
 	default:
 		return -EINVAL;
 	}

 	return 0;
 }

 static enum power_supply_type gpio_charger_get_type(struct device *dev)
 {
 	const char *chargetype;

 	if (!device_property_read_string(dev, "charger-type", &chargetype)) {
 		if (!strcmp("unknown", chargetype))
 			return POWER_SUPPLY_TYPE_UNKNOWN;
 		if (!strcmp("battery", chargetype))
 			return POWER_SUPPLY_TYPE_BATTERY;
 		if (!strcmp("ups", chargetype))
 			return POWER_SUPPLY_TYPE_UPS;
 		if (!strcmp("mains", chargetype))
 			return POWER_SUPPLY_TYPE_MAINS;
 		if (!strcmp("usb-sdp", chargetype))
 			return POWER_SUPPLY_TYPE_USB;
 		if (!strcmp("usb-dcp", chargetype))
 			return POWER_SUPPLY_TYPE_USB;
 		if (!strcmp("usb-cdp", chargetype))
 			return POWER_SUPPLY_TYPE_USB;
 		if (!strcmp("usb-aca", chargetype))
 			return POWER_SUPPLY_TYPE_USB;
 	}
 	dev_warn(dev, "unknown charger type %s\n", chargetype);

 	return POWER_SUPPLY_TYPE_UNKNOWN;
 }

 static int gpio_charger_get_irq(struct device *dev, void *dev_id,
 				struct gpio_desc *gpio)
 {
 	int ret, irq = gpiod_to_irq(gpio);

 	if (irq > 0) {
 		ret = devm_request_any_context_irq(dev, irq, gpio_charger_irq,
 						   IRQF_TRIGGER_RISING |
 						   IRQF_TRIGGER_FALLING,
 						   dev_name(dev),
 						   dev_id);
 		if (ret < 0) {
 			dev_warn(dev, "Failed to request irq: %d\n", ret);
 			irq = 0;
 		}
 	}

 	return irq;
 }

 static enum power_supply_property gpio_charger_properties[] = {
 	POWER_SUPPLY_PROP_ONLINE,
 	POWER_SUPPLY_PROP_STATUS /* Must always be last in the array. */
 };

 static int gpio_charger_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	const struct gpio_charger_platform_data *pdata = dev->platform_data;
 	struct power_supply_config psy_cfg = {};
 	struct gpio_charger *gpio_charger;
 	struct power_supply_desc *charger_desc;
 	struct gpio_desc *charge_status;
 	int charge_status_irq;
 	unsigned long flags;
 	int ret;

 	if (!pdata && !dev->of_node) {
 		dev_err(dev, "No platform data\n");
 		return -ENOENT;
 	}

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

 	/*
 	 * This will fetch a GPIO descriptor from device tree, ACPI or
 	 * boardfile descriptor tables. It's good to try this first.
 	 */
 	gpio_charger->gpiod = devm_gpiod_get(dev, NULL, GPIOD_IN);

 	/*
 	 * If this fails and we're not using device tree, try the
 	 * legacy platform data method.
 	 */
 	if (IS_ERR(gpio_charger->gpiod) && !dev->of_node) {
 		/* Non-DT: use legacy GPIO numbers */
 		if (!gpio_is_valid(pdata->gpio)) {
 			dev_err(dev, "Invalid gpio pin in pdata\n");
 			return -EINVAL;
 		}
 		flags = GPIOF_IN;
 		if (pdata->gpio_active_low)
 			flags |= GPIOF_ACTIVE_LOW;
 		ret = devm_gpio_request_one(dev, pdata->gpio, flags,
 					    dev_name(dev));
 		if (ret) {
 			dev_err(dev, "Failed to request gpio pin: %d\n", ret);
 			return ret;
 		}
 		/* Then convert this to gpiod for now */
 		gpio_charger->gpiod = gpio_to_desc(pdata->gpio);
 	} else if (IS_ERR(gpio_charger->gpiod)) {
 		/* Just try again if this happens */
 		if (PTR_ERR(gpio_charger->gpiod) == -EPROBE_DEFER)
 			return -EPROBE_DEFER;
 		dev_err(dev, "error getting GPIO descriptor\n");
 		return PTR_ERR(gpio_charger->gpiod);
 	}

 	charge_status = devm_gpiod_get_optional(dev, "charge-status", GPIOD_IN);
 	gpio_charger->charge_status = charge_status;
 	if (IS_ERR(gpio_charger->charge_status))
 		return PTR_ERR(gpio_charger->charge_status);

 	charger_desc = &gpio_charger->charger_desc;
 	charger_desc->properties = gpio_charger_properties;
 	charger_desc->num_properties = ARRAY_SIZE(gpio_charger_properties);
 	/* Remove POWER_SUPPLY_PROP_STATUS from the supported properties. */
 	if (!gpio_charger->charge_status)
 		charger_desc->num_properties -= 1;
 	charger_desc->get_property = gpio_charger_get_property;

 	psy_cfg.of_node = dev->of_node;
 	psy_cfg.drv_data = gpio_charger;

 	if (pdata) {
 		charger_desc->name = pdata->name;
 		charger_desc->type = pdata->type;
 		psy_cfg.supplied_to = pdata->supplied_to;
 		psy_cfg.num_supplicants = pdata->num_supplicants;
 	} else {
 		charger_desc->name = dev->of_node->name;
 		charger_desc->type = gpio_charger_get_type(dev);
 	}

 	if (!charger_desc->name)
 		charger_desc->name = pdev->name;

 	gpio_charger->charger = devm_power_supply_register(dev, charger_desc,
 							   &psy_cfg);
 	if (IS_ERR(gpio_charger->charger)) {
 		ret = PTR_ERR(gpio_charger->charger);
 		dev_err(dev, "Failed to register power supply: %d\n", ret);
 		return ret;
 	}

 	gpio_charger->irq = gpio_charger_get_irq(dev, gpio_charger->charger,
 						 gpio_charger->gpiod);

 	charge_status_irq = gpio_charger_get_irq(dev, gpio_charger->charger,
 						 gpio_charger->charge_status);
 	gpio_charger->charge_status_irq = charge_status_irq;

 	platform_set_drvdata(pdev, gpio_charger);

 	device_init_wakeup(dev, 1);

 	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 gpio_charger *gpio_charger = dev_get_drvdata(dev);

 	if (device_may_wakeup(dev) && 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,
 	.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");
	/*
	* 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> /* For legacy platform data */
	#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/gpio/consumer.h>

	#include <linux/power/gpio-charger.h>

	struct gpio_charger {
	unsigned int irq;
	unsigned int charge_status_irq;
	bool wakeup_enabled;

	struct power_supply *charger;
	struct power_supply_desc charger_desc;
	struct gpio_desc *gpiod;
	struct gpio_desc *charge_status;
	};

	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 power_supply_get_drvdata(psy);
	}

	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);

	switch (psp) {
	case POWER_SUPPLY_PROP_ONLINE:
	val->intval = gpiod_get_value_cansleep(gpio_charger->gpiod);
	break;
	case POWER_SUPPLY_PROP_STATUS:
	if (gpiod_get_value_cansleep(gpio_charger->charge_status))
	val->intval = POWER_SUPPLY_STATUS_CHARGING;
	else
	val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
	break;
	default:
	return -EINVAL;
	}

	return 0;
	}

	static enum power_supply_type gpio_charger_get_type(struct device *dev)
	{
	const char *chargetype;

	if (!device_property_read_string(dev, "charger-type", &chargetype)) {
	if (!strcmp("unknown", chargetype))
	return POWER_SUPPLY_TYPE_UNKNOWN;
	if (!strcmp("battery", chargetype))
	return POWER_SUPPLY_TYPE_BATTERY;
	if (!strcmp("ups", chargetype))
	return POWER_SUPPLY_TYPE_UPS;
	if (!strcmp("mains", chargetype))
	return POWER_SUPPLY_TYPE_MAINS;
	if (!strcmp("usb-sdp", chargetype))
	return POWER_SUPPLY_TYPE_USB;
	if (!strcmp("usb-dcp", chargetype))
	return POWER_SUPPLY_TYPE_USB;
	if (!strcmp("usb-cdp", chargetype))
	return POWER_SUPPLY_TYPE_USB;
	if (!strcmp("usb-aca", chargetype))
	return POWER_SUPPLY_TYPE_USB;
	}
	dev_warn(dev, "unknown charger type %s\n", chargetype);

	return POWER_SUPPLY_TYPE_UNKNOWN;
	}

	static int gpio_charger_get_irq(struct device dev, void dev_id,
	struct gpio_desc *gpio)
	{
	int ret, irq = gpiod_to_irq(gpio);

	if (irq > 0) {
	ret = devm_request_any_context_irq(dev, irq, gpio_charger_irq,
	IRQF_TRIGGER_RISING \|
	IRQF_TRIGGER_FALLING,
	dev_name(dev),
	dev_id);
	if (ret < 0) {
	dev_warn(dev, "Failed to request irq: %d\n", ret);
	irq = 0;
	}
	}

	return irq;
	}

	static enum power_supply_property gpio_charger_properties[] = {
	POWER_SUPPLY_PROP_ONLINE,
	POWER_SUPPLY_PROP_STATUS /* Must always be last in the array. */
	};

	static int gpio_charger_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	const struct gpio_charger_platform_data *pdata = dev->platform_data;
	struct power_supply_config psy_cfg = {};
	struct gpio_charger *gpio_charger;
	struct power_supply_desc *charger_desc;
	struct gpio_desc *charge_status;
	int charge_status_irq;
	unsigned long flags;
	int ret;

	if (!pdata && !dev->of_node) {
	dev_err(dev, "No platform data\n");
	return -ENOENT;
	}

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

	/*
	* This will fetch a GPIO descriptor from device tree, ACPI or
	* boardfile descriptor tables. It's good to try this first.
	*/
	gpio_charger->gpiod = devm_gpiod_get(dev, NULL, GPIOD_IN);

	/*
	* If this fails and we're not using device tree, try the
	* legacy platform data method.
	*/
	if (IS_ERR(gpio_charger->gpiod) && !dev->of_node) {
	/* Non-DT: use legacy GPIO numbers */
	if (!gpio_is_valid(pdata->gpio)) {
	dev_err(dev, "Invalid gpio pin in pdata\n");
	return -EINVAL;
	}
	flags = GPIOF_IN;
	if (pdata->gpio_active_low)
	flags \|= GPIOF_ACTIVE_LOW;
	ret = devm_gpio_request_one(dev, pdata->gpio, flags,
	dev_name(dev));
	if (ret) {
	dev_err(dev, "Failed to request gpio pin: %d\n", ret);
	return ret;
	}
	/* Then convert this to gpiod for now */
	gpio_charger->gpiod = gpio_to_desc(pdata->gpio);
	} else if (IS_ERR(gpio_charger->gpiod)) {
	/* Just try again if this happens */
	if (PTR_ERR(gpio_charger->gpiod) == -EPROBE_DEFER)
	return -EPROBE_DEFER;
	dev_err(dev, "error getting GPIO descriptor\n");
	return PTR_ERR(gpio_charger->gpiod);
	}

	charge_status = devm_gpiod_get_optional(dev, "charge-status", GPIOD_IN);
	gpio_charger->charge_status = charge_status;
	if (IS_ERR(gpio_charger->charge_status))
	return PTR_ERR(gpio_charger->charge_status);

	charger_desc = &gpio_charger->charger_desc;
	charger_desc->properties = gpio_charger_properties;
	charger_desc->num_properties = ARRAY_SIZE(gpio_charger_properties);
	/* Remove POWER_SUPPLY_PROP_STATUS from the supported properties. */
	if (!gpio_charger->charge_status)
	charger_desc->num_properties -= 1;
	charger_desc->get_property = gpio_charger_get_property;

	psy_cfg.of_node = dev->of_node;
	psy_cfg.drv_data = gpio_charger;

	if (pdata) {
	charger_desc->name = pdata->name;
	charger_desc->type = pdata->type;
	psy_cfg.supplied_to = pdata->supplied_to;
	psy_cfg.num_supplicants = pdata->num_supplicants;
	} else {
	charger_desc->name = dev->of_node->name;
	charger_desc->type = gpio_charger_get_type(dev);
	}

	if (!charger_desc->name)
	charger_desc->name = pdev->name;

	gpio_charger->charger = devm_power_supply_register(dev, charger_desc,
	&psy_cfg);
	if (IS_ERR(gpio_charger->charger)) {
	ret = PTR_ERR(gpio_charger->charger);
	dev_err(dev, "Failed to register power supply: %d\n", ret);
	return ret;
	}

	gpio_charger->irq = gpio_charger_get_irq(dev, gpio_charger->charger,
	gpio_charger->gpiod);

	charge_status_irq = gpio_charger_get_irq(dev, gpio_charger->charger,
	gpio_charger->charge_status);
	gpio_charger->charge_status_irq = charge_status_irq;

	platform_set_drvdata(pdev, gpio_charger);

	device_init_wakeup(dev, 1);

	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 gpio_charger *gpio_charger = dev_get_drvdata(dev);

	if (device_may_wakeup(dev) && 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,
	.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");