/*
* Intel INT3496 ACPI device extcon driver
*
* Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
*
* Based on android x86 kernel code which is:
*
* Copyright (c) 2014, Intel Corporation.
* Author: David Cohen <david.a.cohen@linux.intel.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/acpi.h>
#include <linux/extcon-provider.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#define INT3496_GPIO_USB_ID 0
#define INT3496_GPIO_VBUS_EN 1
#define INT3496_GPIO_USB_MUX 2
#define DEBOUNCE_TIME msecs_to_jiffies(50)
struct int3496_data {
struct device *dev;
struct extcon_dev *edev;
struct delayed_work work;
struct gpio_desc *gpio_usb_id;
struct gpio_desc *gpio_vbus_en;
struct gpio_desc *gpio_usb_mux;
int usb_id_irq;
};
static const unsigned int int3496_cable[] = {
EXTCON_USB_HOST,
EXTCON_NONE,
};
static const struct acpi_gpio_params id_gpios = { INT3496_GPIO_USB_ID, 0, false };
static const struct acpi_gpio_params vbus_gpios = { INT3496_GPIO_VBUS_EN, 0, false };
static const struct acpi_gpio_params mux_gpios = { INT3496_GPIO_USB_MUX, 0, false };
static const struct acpi_gpio_mapping acpi_int3496_default_gpios[] = {
/*
* Some platforms have a bug in ACPI GPIO description making IRQ
* GPIO to be output only. Ask the GPIO core to ignore this limit.
*/
{ "id-gpios", &id_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
{ "vbus-gpios", &vbus_gpios, 1 },
{ "mux-gpios", &mux_gpios, 1 },
{ },
};
static void int3496_do_usb_id(struct work_struct *work)
{
struct int3496_data *data =
container_of(work, struct int3496_data, work.work);
int id = gpiod_get_value_cansleep(data->gpio_usb_id);
/* id == 1: PERIPHERAL, id == 0: HOST */
dev_dbg(data->dev, "Connected %s cable\n", id ? "PERIPHERAL" : "HOST");
/*
* Peripheral: set USB mux to peripheral and disable VBUS
* Host: set USB mux to host and enable VBUS
*/
if (!IS_ERR(data->gpio_usb_mux))
gpiod_direction_output(data->gpio_usb_mux, id);
if (!IS_ERR(data->gpio_vbus_en))
gpiod_direction_output(data->gpio_vbus_en, !id);
extcon_set_state_sync(data->edev, EXTCON_USB_HOST, !id);
}
static irqreturn_t int3496_thread_isr(int irq, void *priv)
{
struct int3496_data *data = priv;
/* Let the pin settle before processing it */
mod_delayed_work(system_wq, &data->work, DEBOUNCE_TIME);
return IRQ_HANDLED;
}
static int int3496_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct int3496_data *data;
int ret;
ret = devm_acpi_dev_add_driver_gpios(dev, acpi_int3496_default_gpios);
if (ret) {
dev_err(dev, "can't add GPIO ACPI mapping\n");
return ret;
}
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->dev = dev;
INIT_DELAYED_WORK(&data->work, int3496_do_usb_id);
data->gpio_usb_id = devm_gpiod_get(dev, "id", GPIOD_IN);
if (IS_ERR(data->gpio_usb_id)) {
ret = PTR_ERR(data->gpio_usb_id);
dev_err(dev, "can't request USB ID GPIO: %d\n", ret);
return ret;
}
data->usb_id_irq = gpiod_to_irq(data->gpio_usb_id);
if (data->usb_id_irq < 0) {
dev_err(dev, "can't get USB ID IRQ: %d\n", data->usb_id_irq);
return data->usb_id_irq;
}
data->gpio_vbus_en = devm_gpiod_get(dev, "vbus", GPIOD_ASIS);
if (IS_ERR(data->gpio_vbus_en))
dev_info(dev, "can't request VBUS EN GPIO\n");
data->gpio_usb_mux = devm_gpiod_get(dev, "mux", GPIOD_ASIS);
if (IS_ERR(data->gpio_usb_mux))
dev_info(dev, "can't request USB MUX GPIO\n");
/* register extcon device */
data->edev = devm_extcon_dev_allocate(dev, int3496_cable);
if (IS_ERR(data->edev))
return -ENOMEM;
ret = devm_extcon_dev_register(dev, data->edev);
if (ret < 0) {
dev_err(dev, "can't register extcon device: %d\n", ret);
return ret;
}
ret = devm_request_threaded_irq(dev, data->usb_id_irq,
NULL, int3496_thread_isr,
IRQF_SHARED | IRQF_ONESHOT |
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING,
dev_name(dev), data);
if (ret < 0) {
dev_err(dev, "can't request IRQ for USB ID GPIO: %d\n", ret);
return ret;
}
/* process id-pin so that we start with the right status */
queue_delayed_work(system_wq, &data->work, 0);
flush_delayed_work(&data->work);
platform_set_drvdata(pdev, data);
return 0;
}
static int int3496_remove(struct platform_device *pdev)
{
struct int3496_data *data = platform_get_drvdata(pdev);
devm_free_irq(&pdev->dev, data->usb_id_irq, data);
cancel_delayed_work_sync(&data->work);
return 0;
}
static const struct acpi_device_id int3496_acpi_match[] = {
{ "INT3496" },
{ }
};
MODULE_DEVICE_TABLE(acpi, int3496_acpi_match);
static struct platform_driver int3496_driver = {
.driver = {
.name = "intel-int3496",
.acpi_match_table = int3496_acpi_match,
},
.probe = int3496_probe,
.remove = int3496_remove,
};
module_platform_driver(int3496_driver);
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_DESCRIPTION("Intel INT3496 ACPI device extcon driver");
MODULE_LICENSE("GPL");
