268 lines
6.4 KiB
C
268 lines
6.4 KiB
C
/*
|
|
* extcon_gpio.c - Single-state GPIO extcon driver based on extcon class
|
|
*
|
|
* Copyright (C) 2008 Google, Inc.
|
|
* Author: Mike Lockwood <lockwood@android.com>
|
|
*
|
|
* Modified by MyungJoo Ham <myungjoo.ham@samsung.com> to support extcon
|
|
* (originally switch class is supported)
|
|
*
|
|
* This software is licensed under the terms of the GNU General Public
|
|
* License version 2, as published by the Free Software Foundation, and
|
|
* may be copied, distributed, and modified under those terms.
|
|
*
|
|
* 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/extcon/extcon-gpio.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_gpio.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/workqueue.h>
|
|
|
|
struct gpio_extcon_data {
|
|
struct device *dev;
|
|
struct extcon_dev *edev;
|
|
int irq;
|
|
struct delayed_work work;
|
|
unsigned long debounce_jiffies;
|
|
|
|
struct gpio_desc *id_gpiod;
|
|
struct gpio_extcon_pdata *pdata;
|
|
};
|
|
|
|
static void gpio_extcon_work(struct work_struct *work)
|
|
{
|
|
int state;
|
|
int ret;
|
|
struct gpio_extcon_data *data =
|
|
container_of(to_delayed_work(work), struct gpio_extcon_data,
|
|
work);
|
|
|
|
if (gpio_is_valid(data->pdata->gpio)) {
|
|
state = gpiod_get_value_cansleep(data->id_gpiod);
|
|
if (data->pdata->gpio_active_low)
|
|
state = !state;
|
|
} else {
|
|
state = data->pdata->default_state;
|
|
}
|
|
ret = extcon_set_state(data->edev,
|
|
data->pdata->supported_cable[0], state);
|
|
if (ret < 0)
|
|
dev_err(data->dev, "cable state update failed\n");
|
|
}
|
|
|
|
static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
|
|
{
|
|
struct gpio_extcon_data *data = dev_id;
|
|
|
|
queue_delayed_work(system_power_efficient_wq, &data->work,
|
|
data->debounce_jiffies);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int gpio_extcon_init(struct device *dev, struct gpio_extcon_data *data)
|
|
{
|
|
struct gpio_extcon_pdata *pdata = data->pdata;
|
|
int ret;
|
|
|
|
ret = devm_gpio_request_one(dev, pdata->gpio, GPIOF_DIR_IN,
|
|
dev_name(dev));
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
data->id_gpiod = gpio_to_desc(pdata->gpio);
|
|
if (!data->id_gpiod)
|
|
return -EINVAL;
|
|
|
|
if (pdata->debounce) {
|
|
ret = gpiod_set_debounce(data->id_gpiod,
|
|
pdata->debounce * 1000);
|
|
if (ret < 0)
|
|
data->debounce_jiffies =
|
|
msecs_to_jiffies(pdata->debounce);
|
|
}
|
|
|
|
data->irq = gpiod_to_irq(data->id_gpiod);
|
|
if (data->irq < 0)
|
|
return data->irq;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct gpio_extcon_pdata *of_get_platform_data(
|
|
struct platform_device *pdev)
|
|
{
|
|
struct gpio_extcon_pdata *pdata;
|
|
struct device_node *np = pdev->dev.of_node;
|
|
int gpio;
|
|
u32 pval;
|
|
int ret;
|
|
|
|
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
|
|
if (!pdata)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
ret = of_property_read_string(np, "extcon-gpio,name", &pdata->name);
|
|
if (ret < 0)
|
|
pdata->name = np->name;
|
|
|
|
ret = of_property_read_u32_array(np, "extcon-gpio,supported-cable",
|
|
pdata->supported_cable, 2);
|
|
if (ret)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
gpio = of_get_named_gpio(np, "gpio", 0);
|
|
if ((gpio < 0) && (gpio != -ENOENT))
|
|
return ERR_PTR(gpio);
|
|
|
|
if (gpio == -ENOENT)
|
|
pdata->gpio = -1;
|
|
else
|
|
pdata->gpio = gpio;
|
|
|
|
if (pdata->gpio < 0)
|
|
pdata->default_state = of_property_read_bool(np,
|
|
"extcon-gpio,default-connected");
|
|
|
|
ret = of_property_read_u32(np, "extcon-gpio,irq-flags", &pval);
|
|
if (!ret)
|
|
pdata->irq_flags = pval;
|
|
else
|
|
pdata->irq_flags = IRQF_TRIGGER_RISING |
|
|
IRQF_TRIGGER_FALLING;
|
|
|
|
ret = of_property_read_u32(np, "extcon-gpio,debounce", &pval);
|
|
if (!ret)
|
|
pdata->debounce = pval;
|
|
|
|
pdata->gpio_active_low = of_property_read_bool(np,
|
|
"extcon-gpio,connection-state-low");
|
|
|
|
return pdata;
|
|
}
|
|
|
|
static int gpio_extcon_probe(struct platform_device *pdev)
|
|
{
|
|
struct gpio_extcon_pdata *pdata = dev_get_platdata(&pdev->dev);
|
|
struct gpio_extcon_data *data;
|
|
int ret;
|
|
|
|
if (!pdata && pdev->dev.of_node) {
|
|
pdata = of_get_platform_data(pdev);
|
|
if (IS_ERR(pdata))
|
|
return PTR_ERR(pdata);
|
|
}
|
|
|
|
if (!pdata)
|
|
return -EBUSY;
|
|
if (!pdata->irq_flags)
|
|
return -EINVAL;
|
|
|
|
data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
|
|
GFP_KERNEL);
|
|
if (!data)
|
|
return -ENOMEM;
|
|
data->dev = &pdev->dev;
|
|
data->pdata = pdata;
|
|
|
|
/* Allocate the memory of extcon devie and register extcon device */
|
|
data->edev = devm_extcon_dev_allocate(&pdev->dev,
|
|
pdata->supported_cable);
|
|
if (IS_ERR(data->edev)) {
|
|
dev_err(&pdev->dev, "failed to allocate extcon device\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
data->edev->name = pdata->name;
|
|
|
|
ret = devm_extcon_dev_register(&pdev->dev, data->edev);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
INIT_DELAYED_WORK(&data->work, gpio_extcon_work);
|
|
|
|
if (!gpio_is_valid(pdata->gpio))
|
|
goto skip_gpio;
|
|
|
|
/* Initialize the gpio */
|
|
ret = gpio_extcon_init(&pdev->dev, data);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/*
|
|
* Request the interrupt of gpio to detect whether external connector
|
|
* is attached or detached.
|
|
*/
|
|
ret = devm_request_any_context_irq(&pdev->dev, data->irq,
|
|
gpio_irq_handler, pdata->irq_flags,
|
|
pdev->name, data);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
skip_gpio:
|
|
platform_set_drvdata(pdev, data);
|
|
/* Perform initial detection */
|
|
gpio_extcon_work(&data->work.work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int gpio_extcon_remove(struct platform_device *pdev)
|
|
{
|
|
struct gpio_extcon_data *data = platform_get_drvdata(pdev);
|
|
|
|
cancel_delayed_work_sync(&data->work);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int gpio_extcon_resume(struct device *dev)
|
|
{
|
|
struct gpio_extcon_data *data;
|
|
|
|
data = dev_get_drvdata(dev);
|
|
if (data->pdata->check_on_resume)
|
|
queue_delayed_work(system_power_efficient_wq,
|
|
&data->work, data->debounce_jiffies);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(gpio_extcon_pm_ops, NULL, gpio_extcon_resume);
|
|
|
|
static const struct of_device_id of_extcon_gpio_tbl[] = {
|
|
{ .compatible = "extcon-gpio", },
|
|
{ /* end */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, of_extcon_gpio_tbl);
|
|
|
|
static struct platform_driver gpio_extcon_driver = {
|
|
.probe = gpio_extcon_probe,
|
|
.remove = gpio_extcon_remove,
|
|
.driver = {
|
|
.name = "extcon-gpio",
|
|
.pm = &gpio_extcon_pm_ops,
|
|
.of_match_table = of_extcon_gpio_tbl,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(gpio_extcon_driver);
|
|
|
|
MODULE_AUTHOR("Mike Lockwood <lockwood@android.com>");
|
|
MODULE_DESCRIPTION("GPIO extcon driver");
|
|
MODULE_LICENSE("GPL");
|