349 lines
8.5 KiB
C
349 lines
8.5 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* USB GPIO Based Connection Detection Driver
|
|
*
|
|
* Copyright (C) 2019 MediaTek Inc.
|
|
*
|
|
* Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
|
|
*
|
|
* Some code borrowed from drivers/extcon/extcon-usb-gpio.c
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/pinctrl/consumer.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/power_supply.h>
|
|
#include <linux/regulator/consumer.h>
|
|
#include <linux/usb/role.h>
|
|
|
|
#define USB_GPIO_DEB_MS 20 /* ms */
|
|
#define USB_GPIO_DEB_US ((USB_GPIO_DEB_MS) * 1000) /* us */
|
|
|
|
#define USB_CONN_IRQF \
|
|
(IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT)
|
|
|
|
struct usb_conn_info {
|
|
struct device *dev;
|
|
struct usb_role_switch *role_sw;
|
|
enum usb_role last_role;
|
|
struct regulator *vbus;
|
|
struct delayed_work dw_det;
|
|
unsigned long debounce_jiffies;
|
|
|
|
struct gpio_desc *id_gpiod;
|
|
struct gpio_desc *vbus_gpiod;
|
|
int id_irq;
|
|
int vbus_irq;
|
|
|
|
struct power_supply_desc desc;
|
|
struct power_supply *charger;
|
|
};
|
|
|
|
/*
|
|
* "DEVICE" = VBUS and "HOST" = !ID, so we have:
|
|
* Both "DEVICE" and "HOST" can't be set as active at the same time
|
|
* so if "HOST" is active (i.e. ID is 0) we keep "DEVICE" inactive
|
|
* even if VBUS is on.
|
|
*
|
|
* Role | ID | VBUS
|
|
* ------------------------------------
|
|
* [1] DEVICE | H | H
|
|
* [2] NONE | H | L
|
|
* [3] HOST | L | H
|
|
* [4] HOST | L | L
|
|
*
|
|
* In case we have only one of these signals:
|
|
* - VBUS only - we want to distinguish between [1] and [2], so ID is always 1
|
|
* - ID only - we want to distinguish between [1] and [4], so VBUS = ID
|
|
*/
|
|
static void usb_conn_detect_cable(struct work_struct *work)
|
|
{
|
|
struct usb_conn_info *info;
|
|
enum usb_role role;
|
|
int id, vbus, ret;
|
|
|
|
info = container_of(to_delayed_work(work),
|
|
struct usb_conn_info, dw_det);
|
|
|
|
/* check ID and VBUS */
|
|
id = info->id_gpiod ?
|
|
gpiod_get_value_cansleep(info->id_gpiod) : 1;
|
|
vbus = info->vbus_gpiod ?
|
|
gpiod_get_value_cansleep(info->vbus_gpiod) : id;
|
|
|
|
if (!id)
|
|
role = USB_ROLE_HOST;
|
|
else if (vbus)
|
|
role = USB_ROLE_DEVICE;
|
|
else
|
|
role = USB_ROLE_NONE;
|
|
|
|
dev_dbg(info->dev, "role %d/%d, gpios: id %d, vbus %d\n",
|
|
info->last_role, role, id, vbus);
|
|
|
|
if (info->last_role == role) {
|
|
dev_warn(info->dev, "repeated role: %d\n", role);
|
|
return;
|
|
}
|
|
|
|
if (info->last_role == USB_ROLE_HOST && info->vbus)
|
|
regulator_disable(info->vbus);
|
|
|
|
ret = usb_role_switch_set_role(info->role_sw, role);
|
|
if (ret)
|
|
dev_err(info->dev, "failed to set role: %d\n", ret);
|
|
|
|
if (role == USB_ROLE_HOST && info->vbus) {
|
|
ret = regulator_enable(info->vbus);
|
|
if (ret)
|
|
dev_err(info->dev, "enable vbus regulator failed\n");
|
|
}
|
|
|
|
info->last_role = role;
|
|
|
|
if (info->vbus)
|
|
dev_dbg(info->dev, "vbus regulator is %s\n",
|
|
regulator_is_enabled(info->vbus) ? "enabled" : "disabled");
|
|
|
|
power_supply_changed(info->charger);
|
|
}
|
|
|
|
static void usb_conn_queue_dwork(struct usb_conn_info *info,
|
|
unsigned long delay)
|
|
{
|
|
queue_delayed_work(system_power_efficient_wq, &info->dw_det, delay);
|
|
}
|
|
|
|
static irqreturn_t usb_conn_isr(int irq, void *dev_id)
|
|
{
|
|
struct usb_conn_info *info = dev_id;
|
|
|
|
usb_conn_queue_dwork(info, info->debounce_jiffies);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static enum power_supply_property usb_charger_properties[] = {
|
|
POWER_SUPPLY_PROP_ONLINE,
|
|
};
|
|
|
|
static int usb_charger_get_property(struct power_supply *psy,
|
|
enum power_supply_property psp,
|
|
union power_supply_propval *val)
|
|
{
|
|
struct usb_conn_info *info = power_supply_get_drvdata(psy);
|
|
|
|
switch (psp) {
|
|
case POWER_SUPPLY_PROP_ONLINE:
|
|
val->intval = info->last_role == USB_ROLE_DEVICE;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int usb_conn_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct power_supply_desc *desc;
|
|
struct usb_conn_info *info;
|
|
struct power_supply_config cfg = {
|
|
.of_node = dev->of_node,
|
|
};
|
|
bool need_vbus = true;
|
|
int ret = 0;
|
|
|
|
info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
|
|
if (!info)
|
|
return -ENOMEM;
|
|
|
|
info->dev = dev;
|
|
info->id_gpiod = devm_gpiod_get_optional(dev, "id", GPIOD_IN);
|
|
if (IS_ERR(info->id_gpiod))
|
|
return PTR_ERR(info->id_gpiod);
|
|
|
|
info->vbus_gpiod = devm_gpiod_get_optional(dev, "vbus", GPIOD_IN);
|
|
if (IS_ERR(info->vbus_gpiod))
|
|
return PTR_ERR(info->vbus_gpiod);
|
|
|
|
if (!info->id_gpiod && !info->vbus_gpiod) {
|
|
dev_err(dev, "failed to get gpios\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
if (info->id_gpiod)
|
|
ret = gpiod_set_debounce(info->id_gpiod, USB_GPIO_DEB_US);
|
|
if (!ret && info->vbus_gpiod)
|
|
ret = gpiod_set_debounce(info->vbus_gpiod, USB_GPIO_DEB_US);
|
|
if (ret < 0)
|
|
info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEB_MS);
|
|
|
|
INIT_DELAYED_WORK(&info->dw_det, usb_conn_detect_cable);
|
|
|
|
/*
|
|
* If the USB connector is a child of a USB port and that port already provides the VBUS
|
|
* supply, there's no need for the USB connector to provide it again.
|
|
*/
|
|
if (dev->parent && dev->parent->of_node) {
|
|
if (of_find_property(dev->parent->of_node, "vbus-supply", NULL))
|
|
need_vbus = false;
|
|
}
|
|
|
|
if (!need_vbus) {
|
|
info->vbus = devm_regulator_get_optional(dev, "vbus");
|
|
if (PTR_ERR(info->vbus) == -ENODEV)
|
|
info->vbus = NULL;
|
|
} else {
|
|
info->vbus = devm_regulator_get(dev, "vbus");
|
|
}
|
|
|
|
if (IS_ERR(info->vbus)) {
|
|
if (PTR_ERR(info->vbus) != -EPROBE_DEFER)
|
|
dev_err(dev, "failed to get vbus: %ld\n", PTR_ERR(info->vbus));
|
|
return PTR_ERR(info->vbus);
|
|
}
|
|
|
|
info->role_sw = usb_role_switch_get(dev);
|
|
if (IS_ERR(info->role_sw)) {
|
|
if (PTR_ERR(info->role_sw) != -EPROBE_DEFER)
|
|
dev_err(dev, "failed to get role switch\n");
|
|
|
|
return PTR_ERR(info->role_sw);
|
|
}
|
|
|
|
if (info->id_gpiod) {
|
|
info->id_irq = gpiod_to_irq(info->id_gpiod);
|
|
if (info->id_irq < 0) {
|
|
dev_err(dev, "failed to get ID IRQ\n");
|
|
ret = info->id_irq;
|
|
goto put_role_sw;
|
|
}
|
|
|
|
ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
|
|
usb_conn_isr, USB_CONN_IRQF,
|
|
pdev->name, info);
|
|
if (ret < 0) {
|
|
dev_err(dev, "failed to request ID IRQ\n");
|
|
goto put_role_sw;
|
|
}
|
|
}
|
|
|
|
if (info->vbus_gpiod) {
|
|
info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
|
|
if (info->vbus_irq < 0) {
|
|
dev_err(dev, "failed to get VBUS IRQ\n");
|
|
ret = info->vbus_irq;
|
|
goto put_role_sw;
|
|
}
|
|
|
|
ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
|
|
usb_conn_isr, USB_CONN_IRQF,
|
|
pdev->name, info);
|
|
if (ret < 0) {
|
|
dev_err(dev, "failed to request VBUS IRQ\n");
|
|
goto put_role_sw;
|
|
}
|
|
}
|
|
|
|
desc = &info->desc;
|
|
desc->name = "usb-charger";
|
|
desc->properties = usb_charger_properties;
|
|
desc->num_properties = ARRAY_SIZE(usb_charger_properties);
|
|
desc->get_property = usb_charger_get_property;
|
|
desc->type = POWER_SUPPLY_TYPE_USB;
|
|
cfg.drv_data = info;
|
|
|
|
info->charger = devm_power_supply_register(dev, desc, &cfg);
|
|
if (IS_ERR(info->charger)) {
|
|
dev_err(dev, "Unable to register charger\n");
|
|
return PTR_ERR(info->charger);
|
|
}
|
|
|
|
platform_set_drvdata(pdev, info);
|
|
|
|
/* Perform initial detection */
|
|
usb_conn_queue_dwork(info, 0);
|
|
|
|
return 0;
|
|
|
|
put_role_sw:
|
|
usb_role_switch_put(info->role_sw);
|
|
return ret;
|
|
}
|
|
|
|
static int usb_conn_remove(struct platform_device *pdev)
|
|
{
|
|
struct usb_conn_info *info = platform_get_drvdata(pdev);
|
|
|
|
cancel_delayed_work_sync(&info->dw_det);
|
|
|
|
if (info->last_role == USB_ROLE_HOST && info->vbus)
|
|
regulator_disable(info->vbus);
|
|
|
|
usb_role_switch_put(info->role_sw);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused usb_conn_suspend(struct device *dev)
|
|
{
|
|
struct usb_conn_info *info = dev_get_drvdata(dev);
|
|
|
|
if (info->id_gpiod)
|
|
disable_irq(info->id_irq);
|
|
if (info->vbus_gpiod)
|
|
disable_irq(info->vbus_irq);
|
|
|
|
pinctrl_pm_select_sleep_state(dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused usb_conn_resume(struct device *dev)
|
|
{
|
|
struct usb_conn_info *info = dev_get_drvdata(dev);
|
|
|
|
pinctrl_pm_select_default_state(dev);
|
|
|
|
if (info->id_gpiod)
|
|
enable_irq(info->id_irq);
|
|
if (info->vbus_gpiod)
|
|
enable_irq(info->vbus_irq);
|
|
|
|
usb_conn_queue_dwork(info, 0);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(usb_conn_pm_ops,
|
|
usb_conn_suspend, usb_conn_resume);
|
|
|
|
static const struct of_device_id usb_conn_dt_match[] = {
|
|
{ .compatible = "gpio-usb-b-connector", },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, usb_conn_dt_match);
|
|
|
|
static struct platform_driver usb_conn_driver = {
|
|
.probe = usb_conn_probe,
|
|
.remove = usb_conn_remove,
|
|
.driver = {
|
|
.name = "usb-conn-gpio",
|
|
.pm = &usb_conn_pm_ops,
|
|
.of_match_table = usb_conn_dt_match,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(usb_conn_driver);
|
|
|
|
MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
|
|
MODULE_DESCRIPTION("USB GPIO based connection detection driver");
|
|
MODULE_LICENSE("GPL v2");
|