linuxdebug/drivers/extcon/extcon-adc-jack.c

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2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/extcon/extcon-adc-jack.c
*
* Analog Jack extcon driver with ADC-based detection capability.
*
* Copyright (C) 2016 Samsung Electronics
* Chanwoo Choi <cw00.choi@samsung.com>
*
* Copyright (C) 2012 Samsung Electronics
* MyungJoo Ham <myungjoo.ham@samsung.com>
*
* Modified for calling to IIO to get adc by <anish.singh@samsung.com>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/iio/consumer.h>
#include <linux/extcon/extcon-adc-jack.h>
#include <linux/extcon-provider.h>
/**
* struct adc_jack_data - internal data for adc_jack device driver
* @edev: extcon device.
* @cable_names: list of supported cables.
* @adc_conditions: list of adc value conditions.
* @num_conditions: size of adc_conditions.
* @irq: irq number of attach/detach event (0 if not exist).
* @handling_delay: interrupt handler will schedule extcon event
* handling at handling_delay jiffies.
* @handler: extcon event handler called by interrupt handler.
* @chan: iio channel being queried.
*/
struct adc_jack_data {
struct device *dev;
struct extcon_dev *edev;
const unsigned int **cable_names;
struct adc_jack_cond *adc_conditions;
int num_conditions;
int irq;
unsigned long handling_delay; /* in jiffies */
struct delayed_work handler;
struct iio_channel *chan;
bool wakeup_source;
};
static void adc_jack_handler(struct work_struct *work)
{
struct adc_jack_data *data = container_of(to_delayed_work(work),
struct adc_jack_data,
handler);
struct adc_jack_cond *def;
int ret, adc_val;
int i;
ret = iio_read_channel_raw(data->chan, &adc_val);
if (ret < 0) {
dev_err(data->dev, "read channel() error: %d\n", ret);
return;
}
/* Get state from adc value with adc_conditions */
for (i = 0; i < data->num_conditions; i++) {
def = &data->adc_conditions[i];
if (def->min_adc <= adc_val && def->max_adc >= adc_val) {
extcon_set_state_sync(data->edev, def->id, true);
return;
}
}
/* Set the detached state if adc value is not included in the range */
for (i = 0; i < data->num_conditions; i++) {
def = &data->adc_conditions[i];
extcon_set_state_sync(data->edev, def->id, false);
}
}
static irqreturn_t adc_jack_irq_thread(int irq, void *_data)
{
struct adc_jack_data *data = _data;
queue_delayed_work(system_power_efficient_wq,
&data->handler, data->handling_delay);
return IRQ_HANDLED;
}
static int adc_jack_probe(struct platform_device *pdev)
{
struct adc_jack_data *data;
struct adc_jack_pdata *pdata = dev_get_platdata(&pdev->dev);
int i, err = 0;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
if (!pdata->cable_names) {
dev_err(&pdev->dev, "error: cable_names not defined.\n");
return -EINVAL;
}
data->dev = &pdev->dev;
data->edev = devm_extcon_dev_allocate(&pdev->dev, pdata->cable_names);
if (IS_ERR(data->edev)) {
dev_err(&pdev->dev, "failed to allocate extcon device\n");
return -ENOMEM;
}
if (!pdata->adc_conditions) {
dev_err(&pdev->dev, "error: adc_conditions not defined.\n");
return -EINVAL;
}
data->adc_conditions = pdata->adc_conditions;
/* Check the length of array and set num_conditions */
for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++);
data->num_conditions = i;
data->chan = devm_iio_channel_get(&pdev->dev, pdata->consumer_channel);
if (IS_ERR(data->chan))
return PTR_ERR(data->chan);
data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms);
data->wakeup_source = pdata->wakeup_source;
INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler);
platform_set_drvdata(pdev, data);
err = devm_extcon_dev_register(&pdev->dev, data->edev);
if (err)
return err;
data->irq = platform_get_irq(pdev, 0);
if (data->irq < 0)
return -ENODEV;
err = request_any_context_irq(data->irq, adc_jack_irq_thread,
pdata->irq_flags, pdata->name, data);
if (err < 0) {
dev_err(&pdev->dev, "error: irq %d\n", data->irq);
return err;
}
if (data->wakeup_source)
device_init_wakeup(&pdev->dev, 1);
adc_jack_handler(&data->handler.work);
return 0;
}
static int adc_jack_remove(struct platform_device *pdev)
{
struct adc_jack_data *data = platform_get_drvdata(pdev);
free_irq(data->irq, data);
cancel_work_sync(&data->handler.work);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int adc_jack_suspend(struct device *dev)
{
struct adc_jack_data *data = dev_get_drvdata(dev);
cancel_delayed_work_sync(&data->handler);
if (device_may_wakeup(data->dev))
enable_irq_wake(data->irq);
return 0;
}
static int adc_jack_resume(struct device *dev)
{
struct adc_jack_data *data = dev_get_drvdata(dev);
if (device_may_wakeup(data->dev))
disable_irq_wake(data->irq);
return 0;
}
#endif /* CONFIG_PM_SLEEP */
static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops,
adc_jack_suspend, adc_jack_resume);
static struct platform_driver adc_jack_driver = {
.probe = adc_jack_probe,
.remove = adc_jack_remove,
.driver = {
.name = "adc-jack",
.pm = &adc_jack_pm_ops,
},
};
module_platform_driver(adc_jack_driver);
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_DESCRIPTION("ADC Jack extcon driver");
MODULE_LICENSE("GPL v2");