mirror of https://gitee.com/openkylin/linux.git
238 lines
5.7 KiB
C
238 lines
5.7 KiB
C
/**
|
|
* 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/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>
|
|
|
|
#define USB_GPIO_DEBOUNCE_MS 20 /* ms */
|
|
|
|
struct usb_extcon_info {
|
|
struct device *dev;
|
|
struct extcon_dev *edev;
|
|
|
|
struct gpio_desc *id_gpiod;
|
|
int id_irq;
|
|
|
|
unsigned long debounce_jiffies;
|
|
struct delayed_work wq_detcable;
|
|
};
|
|
|
|
/* List of detectable cables */
|
|
enum {
|
|
EXTCON_CABLE_USB = 0,
|
|
EXTCON_CABLE_USB_HOST,
|
|
|
|
EXTCON_CABLE_END,
|
|
};
|
|
|
|
static const char *usb_extcon_cable[] = {
|
|
[EXTCON_CABLE_USB] = "USB",
|
|
[EXTCON_CABLE_USB_HOST] = "USB-HOST",
|
|
NULL,
|
|
};
|
|
|
|
static void usb_extcon_detect_cable(struct work_struct *work)
|
|
{
|
|
int id;
|
|
struct usb_extcon_info *info = container_of(to_delayed_work(work),
|
|
struct usb_extcon_info,
|
|
wq_detcable);
|
|
|
|
/* check ID and update cable state */
|
|
id = gpiod_get_value_cansleep(info->id_gpiod);
|
|
if (id) {
|
|
/*
|
|
* ID = 1 means USB HOST cable detached.
|
|
* As we don't have event for USB peripheral cable attached,
|
|
* we simulate USB peripheral attach here.
|
|
*/
|
|
extcon_set_cable_state(info->edev,
|
|
usb_extcon_cable[EXTCON_CABLE_USB_HOST],
|
|
false);
|
|
extcon_set_cable_state(info->edev,
|
|
usb_extcon_cable[EXTCON_CABLE_USB],
|
|
true);
|
|
} else {
|
|
/*
|
|
* ID = 0 means USB HOST cable attached.
|
|
* As we don't have event for USB peripheral cable detached,
|
|
* we simulate USB peripheral detach here.
|
|
*/
|
|
extcon_set_cable_state(info->edev,
|
|
usb_extcon_cable[EXTCON_CABLE_USB],
|
|
false);
|
|
extcon_set_cable_state(info->edev,
|
|
usb_extcon_cable[EXTCON_CABLE_USB_HOST],
|
|
true);
|
|
}
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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)
|
|
return -EINVAL;
|
|
|
|
info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
|
|
if (!info)
|
|
return -ENOMEM;
|
|
|
|
info->dev = dev;
|
|
info->id_gpiod = devm_gpiod_get(&pdev->dev, "id");
|
|
if (IS_ERR(info->id_gpiod)) {
|
|
dev_err(dev, "failed to get ID GPIO\n");
|
|
return PTR_ERR(info->id_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;
|
|
}
|
|
|
|
ret = gpiod_set_debounce(info->id_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);
|
|
|
|
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;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, info);
|
|
device_init_wakeup(dev, 1);
|
|
|
|
/* Perform initial detection */
|
|
usb_extcon_detect_cable(&info->wq_detcable.work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#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)) {
|
|
ret = enable_irq_wake(info->id_irq);
|
|
if (ret)
|
|
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.
|
|
*/
|
|
disable_irq(info->id_irq);
|
|
|
|
return ret;
|
|
}
|
|
|
|
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)) {
|
|
ret = disable_irq_wake(info->id_irq);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
enable_irq(info->id_irq);
|
|
|
|
return ret;
|
|
}
|
|
#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 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,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(usb_extcon_driver);
|
|
|
|
MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>");
|
|
MODULE_DESCRIPTION("USB GPIO extcon driver");
|
|
MODULE_LICENSE("GPL v2");
|