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Release 4.11 drivers/extcon/extcon-usb-gpio.c

Directory: drivers/extcon
/**
 * drivers/extcon/extcon-usb-gpio.c - USB GPIO extcon driver
 *
 * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
 * Author: Roger Quadros <rogerq@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/extcon.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/acpi.h>
#include <linux/pinctrl/consumer.h>


#define USB_GPIO_DEBOUNCE_MS	20	
/* ms */


struct usb_extcon_info {
	
struct device *dev;
	
struct extcon_dev *edev;

	
struct gpio_desc *id_gpiod;
	
struct gpio_desc *vbus_gpiod;
	
int id_irq;
	
int vbus_irq;

	
unsigned long debounce_jiffies;
	
struct delayed_work wq_detcable;
};


static const unsigned int usb_extcon_cable[] = {
	EXTCON_USB,
	EXTCON_USB_HOST,
	EXTCON_NONE,
};

/*
 * "USB" = VBUS and "USB-HOST" = !ID, so we have:
 * Both "USB" and "USB-HOST" can't be set as active at the
 * same time so if "USB-HOST" is active (i.e. ID is 0)  we keep "USB" inactive
 * even if VBUS is on.
 *
 *  State              |    ID   |   VBUS
 * ----------------------------------------
 *  [1] USB            |    H    |    H
 *  [2] none           |    H    |    L
 *  [3] USB-HOST       |    L    |    H
 *  [4] USB-HOST       |    L    |    L
 *
 * In case we have only one of these signals:
 * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1.
 * - ID only - we want to distinguish between [1] and [4], so VBUS = ID.
*/



static void usb_extcon_detect_cable(struct work_struct *work)
{
	int id, vbus;
	struct usb_extcon_info *info = container_of(to_delayed_work(work),
						    struct usb_extcon_info,
						    wq_detcable);

	/* check ID and VBUS and update cable state */
	id = info->id_gpiod ?
		gpiod_get_value_cansleep(info->id_gpiod) : 1;
	vbus = info->vbus_gpiod ?
		gpiod_get_value_cansleep(info->vbus_gpiod) : id;

	/* at first we clean states which are no longer active */
	if (id)
		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, false);
	if (!vbus)
		extcon_set_state_sync(info->edev, EXTCON_USB, false);

	if (!id) {
		extcon_set_state_sync(info->edev, EXTCON_USB_HOST, true);
	} else {
		if (vbus)
			extcon_set_state_sync(info->edev, EXTCON_USB, true);
	}
}


Contributors
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Roger Quadros12795.49%250.00%


Chanwoo Choi64.51%250.00%


Total133100.00%4100.00%






static irqreturn_t usb_irq_handler(int irq, void *dev_id)
{
	struct usb_extcon_info *info = dev_id;

	queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
			   info->debounce_jiffies);

	return IRQ_HANDLED;
}


Contributors
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Roger Quadros37100.00%1100.00%


Total37100.00%1100.00%






static int usb_extcon_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct usb_extcon_info *info;
	int ret;

	if (!np && !ACPI_HANDLE(dev))
		return -EINVAL;

	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	info->dev = dev;
	info->id_gpiod = devm_gpiod_get_optional(&pdev->dev, "id", GPIOD_IN);
	info->vbus_gpiod = devm_gpiod_get_optional(&pdev->dev, "vbus",
						   GPIOD_IN);

	if (!info->id_gpiod && !info->vbus_gpiod) {
		dev_err(dev, "failed to get gpios\n");
		return -ENODEV;
	}

	if (IS_ERR(info->id_gpiod))
		return PTR_ERR(info->id_gpiod);

	if (IS_ERR(info->vbus_gpiod))
		return PTR_ERR(info->vbus_gpiod);

	info->edev = devm_extcon_dev_allocate(dev, usb_extcon_cable);
	if (IS_ERR(info->edev)) {
		dev_err(dev, "failed to allocate extcon device\n");
		return -ENOMEM;
	}

	ret = devm_extcon_dev_register(dev, info->edev);
	if (ret < 0) {
		dev_err(dev, "failed to register extcon device\n");
		return ret;
	}

	if (info->id_gpiod)
		ret = gpiod_set_debounce(info->id_gpiod,
					 USB_GPIO_DEBOUNCE_MS * 1000);
	if (!ret && info->vbus_gpiod)
		ret = gpiod_set_debounce(info->vbus_gpiod,
					 USB_GPIO_DEBOUNCE_MS * 1000);

	if (ret < 0)
		info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEBOUNCE_MS);

	INIT_DELAYED_WORK(&info->wq_detcable, usb_extcon_detect_cable);

	if (info->id_gpiod) {
		info->id_irq = gpiod_to_irq(info->id_gpiod);
		if (info->id_irq < 0) {
			dev_err(dev, "failed to get ID IRQ\n");
			return info->id_irq;
		}

		ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
						usb_irq_handler,
						IRQF_TRIGGER_RISING |
						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
						pdev->name, info);
		if (ret < 0) {
			dev_err(dev, "failed to request handler for ID IRQ\n");
			return ret;
		}
	}

	if (info->vbus_gpiod) {
		info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
		if (info->vbus_irq < 0) {
			dev_err(dev, "failed to get VBUS IRQ\n");
			return info->vbus_irq;
		}

		ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
						usb_irq_handler,
						IRQF_TRIGGER_RISING |
						IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
						pdev->name, info);
		if (ret < 0) {
			dev_err(dev, "failed to request handler for VBUS IRQ\n");
			return ret;
		}
	}

	platform_set_drvdata(pdev, info);
	device_init_wakeup(dev, true);

	/* Perform initial detection */
	usb_extcon_detect_cable(&info->wq_detcable.work);

	return 0;
}


Contributors
PersonTokensPropCommitsCommitProp
Roger Quadros42884.75%233.33%


Robert Baldyga6212.28%116.67%


Grygorii Strashko71.39%116.67%


Lu Baolu61.19%116.67%


Uwe Kleine-König20.40%116.67%


Total505100.00%6100.00%






static int usb_extcon_remove(struct platform_device *pdev)
{
	struct usb_extcon_info *info = platform_get_drvdata(pdev);

	cancel_delayed_work_sync(&info->wq_detcable);
	device_init_wakeup(&pdev->dev, false);

	return 0;
}


Contributors
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Roger Quadros3276.19%150.00%


Grygorii Strashko1023.81%150.00%


Total42100.00%2100.00%



#ifdef CONFIG_PM_SLEEP



static int usb_extcon_suspend(struct device *dev)
{
	struct usb_extcon_info *info = dev_get_drvdata(dev);
	int ret = 0;

	if (device_may_wakeup(dev)) {
		if (info->id_gpiod) {
			ret = enable_irq_wake(info->id_irq);
			if (ret)
				return ret;
		}
		if (info->vbus_gpiod) {
			ret = enable_irq_wake(info->vbus_irq);
			if (ret) {
				if (info->id_gpiod)
					disable_irq_wake(info->id_irq);

				return ret;
			}
		}
	}

	/*
         * We don't want to process any IRQs after this point
         * as GPIOs used behind I2C subsystem might not be
         * accessible until resume completes. So disable IRQ.
         */
	if (info->id_gpiod)
		disable_irq(info->id_irq);
	if (info->vbus_gpiod)
		disable_irq(info->vbus_irq);

	if (!device_may_wakeup(dev))
		pinctrl_pm_select_sleep_state(dev);

	return ret;
}


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Roger Quadros12890.78%266.67%


Peter Chen139.22%133.33%


Total141100.00%3100.00%






static int usb_extcon_resume(struct device *dev)
{
	struct usb_extcon_info *info = dev_get_drvdata(dev);
	int ret = 0;

	if (!device_may_wakeup(dev))
		pinctrl_pm_select_default_state(dev);

	if (device_may_wakeup(dev)) {
		if (info->id_gpiod) {
			ret = disable_irq_wake(info->id_irq);
			if (ret)
				return ret;
		}
		if (info->vbus_gpiod) {
			ret = disable_irq_wake(info->vbus_irq);
			if (ret) {
				if (info->id_gpiod)
					enable_irq_wake(info->id_irq);

				return ret;
			}
		}
	}

	if (info->id_gpiod)
		enable_irq(info->id_irq);
	if (info->vbus_gpiod)
		enable_irq(info->vbus_irq);

	if (!device_may_wakeup(dev))
		queue_delayed_work(system_power_efficient_wq,
				   &info->wq_detcable, 0);

	return ret;
}

Contributors
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Roger Quadros14791.88%375.00%


Peter Chen138.12%125.00%


Total160100.00%4100.00%



#endif

static SIMPLE_DEV_PM_OPS(usb_extcon_pm_ops,
			 usb_extcon_suspend, usb_extcon_resume);


static const struct of_device_id usb_extcon_dt_match[] = {
	{ .compatible = "linux,extcon-usb-gpio", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, usb_extcon_dt_match);


static const struct platform_device_id usb_extcon_platform_ids[] = {
	{ .name = "extcon-usb-gpio", },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, usb_extcon_platform_ids);


static struct platform_driver usb_extcon_driver = {
	.probe		= usb_extcon_probe,
	.remove		= usb_extcon_remove,
	.driver		= {
		.name	= "extcon-usb-gpio",
		.pm	= &usb_extcon_pm_ops,
		.of_match_table = usb_extcon_dt_match,
        },
	.id_table = usb_extcon_platform_ids,
};


module_platform_driver(usb_extcon_driver);

MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
MODULE_DESCRIPTION("USB GPIO extcon driver");
MODULE_LICENSE("GPL v2");

Overall Contributors
PersonTokensPropCommitsCommitProp
Roger Quadros108786.75%426.67%


Robert Baldyga624.95%16.67%


Lu Baolu413.27%213.33%


Peter Chen292.31%16.67%


Grygorii Strashko171.36%16.67%


Chanwoo Choi120.96%426.67%


Geert Uytterhoeven30.24%16.67%


Uwe Kleine-König20.16%16.67%


Total1253100.00%15100.00%


Directory: drivers/extcon



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