148 lines
3.7 KiB
C
148 lines
3.7 KiB
C
/*
|
|
* Maxim Integrated MAX3355 USB OTG chip extcon driver
|
|
*
|
|
* Copyright (C) 2014-2015 Cogent Embedded, Inc.
|
|
* Author: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#include <linux/extcon-provider.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mod_devicetable.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
struct max3355_data {
|
|
struct extcon_dev *edev;
|
|
struct gpio_desc *id_gpiod;
|
|
struct gpio_desc *shdn_gpiod;
|
|
};
|
|
|
|
static const unsigned int max3355_cable[] = {
|
|
EXTCON_USB,
|
|
EXTCON_USB_HOST,
|
|
EXTCON_NONE,
|
|
};
|
|
|
|
static irqreturn_t max3355_id_irq(int irq, void *dev_id)
|
|
{
|
|
struct max3355_data *data = dev_id;
|
|
int id = gpiod_get_value_cansleep(data->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_state_sync(data->edev, EXTCON_USB_HOST, false);
|
|
extcon_set_state_sync(data->edev, EXTCON_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_state_sync(data->edev, EXTCON_USB, false);
|
|
extcon_set_state_sync(data->edev, EXTCON_USB_HOST, true);
|
|
}
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int max3355_probe(struct platform_device *pdev)
|
|
{
|
|
struct max3355_data *data;
|
|
struct gpio_desc *gpiod;
|
|
int irq, err;
|
|
|
|
data = devm_kzalloc(&pdev->dev, sizeof(struct max3355_data),
|
|
GFP_KERNEL);
|
|
if (!data)
|
|
return -ENOMEM;
|
|
|
|
gpiod = devm_gpiod_get(&pdev->dev, "id", GPIOD_IN);
|
|
if (IS_ERR(gpiod)) {
|
|
dev_err(&pdev->dev, "failed to get ID_OUT GPIO\n");
|
|
return PTR_ERR(gpiod);
|
|
}
|
|
data->id_gpiod = gpiod;
|
|
|
|
gpiod = devm_gpiod_get(&pdev->dev, "maxim,shdn", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(gpiod)) {
|
|
dev_err(&pdev->dev, "failed to get SHDN# GPIO\n");
|
|
return PTR_ERR(gpiod);
|
|
}
|
|
data->shdn_gpiod = gpiod;
|
|
|
|
data->edev = devm_extcon_dev_allocate(&pdev->dev, max3355_cable);
|
|
if (IS_ERR(data->edev)) {
|
|
dev_err(&pdev->dev, "failed to allocate extcon device\n");
|
|
return PTR_ERR(data->edev);
|
|
}
|
|
|
|
err = devm_extcon_dev_register(&pdev->dev, data->edev);
|
|
if (err < 0) {
|
|
dev_err(&pdev->dev, "failed to register extcon device\n");
|
|
return err;
|
|
}
|
|
|
|
irq = gpiod_to_irq(data->id_gpiod);
|
|
if (irq < 0) {
|
|
dev_err(&pdev->dev, "failed to translate ID_OUT GPIO to IRQ\n");
|
|
return irq;
|
|
}
|
|
|
|
err = devm_request_threaded_irq(&pdev->dev, irq, NULL, max3355_id_irq,
|
|
IRQF_ONESHOT | IRQF_NO_SUSPEND |
|
|
IRQF_TRIGGER_RISING |
|
|
IRQF_TRIGGER_FALLING,
|
|
pdev->name, data);
|
|
if (err < 0) {
|
|
dev_err(&pdev->dev, "failed to request ID_OUT IRQ\n");
|
|
return err;
|
|
}
|
|
|
|
platform_set_drvdata(pdev, data);
|
|
|
|
/* Perform initial detection */
|
|
max3355_id_irq(irq, data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int max3355_remove(struct platform_device *pdev)
|
|
{
|
|
struct max3355_data *data = platform_get_drvdata(pdev);
|
|
|
|
gpiod_set_value_cansleep(data->shdn_gpiod, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id max3355_match_table[] = {
|
|
{ .compatible = "maxim,max3355", },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, max3355_match_table);
|
|
|
|
static struct platform_driver max3355_driver = {
|
|
.probe = max3355_probe,
|
|
.remove = max3355_remove,
|
|
.driver = {
|
|
.name = "extcon-max3355",
|
|
.of_match_table = max3355_match_table,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(max3355_driver);
|
|
|
|
MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");
|
|
MODULE_DESCRIPTION("Maxim MAX3355 extcon driver");
|
|
MODULE_LICENSE("GPL v2");
|