WSL2-Linux-Kernel/drivers/thunderbolt/usb4_port.c

319 строки
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* USB4 port device
*
* Copyright (C) 2021, Intel Corporation
* Author: Mika Westerberg <mika.westerberg@linux.intel.com>
*/
#include <linux/pm_runtime.h>
#include <linux/component.h>
#include <linux/property.h>
#include "tb.h"
static int connector_bind(struct device *dev, struct device *connector, void *data)
{
int ret;
ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
if (ret)
return ret;
ret = sysfs_create_link(&connector->kobj, &dev->kobj, dev_name(dev));
if (ret)
sysfs_remove_link(&dev->kobj, "connector");
return ret;
}
static void connector_unbind(struct device *dev, struct device *connector, void *data)
{
sysfs_remove_link(&connector->kobj, dev_name(dev));
sysfs_remove_link(&dev->kobj, "connector");
}
static const struct component_ops connector_ops = {
.bind = connector_bind,
.unbind = connector_unbind,
};
static ssize_t link_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
struct tb_port *port = usb4->port;
struct tb *tb = port->sw->tb;
const char *link;
if (mutex_lock_interruptible(&tb->lock))
return -ERESTARTSYS;
if (tb_is_upstream_port(port))
link = port->sw->link_usb4 ? "usb4" : "tbt";
else if (tb_port_has_remote(port))
link = port->remote->sw->link_usb4 ? "usb4" : "tbt";
else
link = "none";
mutex_unlock(&tb->lock);
return sysfs_emit(buf, "%s\n", link);
}
static DEVICE_ATTR_RO(link);
static struct attribute *common_attrs[] = {
&dev_attr_link.attr,
NULL
};
static const struct attribute_group common_group = {
.attrs = common_attrs,
};
static int usb4_port_offline(struct usb4_port *usb4)
{
struct tb_port *port = usb4->port;
int ret;
ret = tb_acpi_power_on_retimers(port);
if (ret)
return ret;
ret = usb4_port_router_offline(port);
if (ret) {
tb_acpi_power_off_retimers(port);
return ret;
}
ret = tb_retimer_scan(port, false);
if (ret) {
usb4_port_router_online(port);
tb_acpi_power_off_retimers(port);
}
return ret;
}
static void usb4_port_online(struct usb4_port *usb4)
{
struct tb_port *port = usb4->port;
usb4_port_router_online(port);
tb_acpi_power_off_retimers(port);
}
static ssize_t offline_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
return sysfs_emit(buf, "%d\n", usb4->offline);
}
static ssize_t offline_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
struct tb_port *port = usb4->port;
struct tb *tb = port->sw->tb;
bool val;
int ret;
ret = kstrtobool(buf, &val);
if (ret)
return ret;
pm_runtime_get_sync(&usb4->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out_rpm;
}
if (val == usb4->offline)
goto out_unlock;
/* Offline mode works only for ports that are not connected */
if (tb_port_has_remote(port)) {
ret = -EBUSY;
goto out_unlock;
}
if (val) {
ret = usb4_port_offline(usb4);
if (ret)
goto out_unlock;
} else {
usb4_port_online(usb4);
tb_retimer_remove_all(port);
}
usb4->offline = val;
tb_port_dbg(port, "%s offline mode\n", val ? "enter" : "exit");
out_unlock:
mutex_unlock(&tb->lock);
out_rpm:
pm_runtime_mark_last_busy(&usb4->dev);
pm_runtime_put_autosuspend(&usb4->dev);
return ret ? ret : count;
}
static DEVICE_ATTR_RW(offline);
static ssize_t rescan_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
struct tb_port *port = usb4->port;
struct tb *tb = port->sw->tb;
bool val;
int ret;
ret = kstrtobool(buf, &val);
if (ret)
return ret;
if (!val)
return count;
pm_runtime_get_sync(&usb4->dev);
if (mutex_lock_interruptible(&tb->lock)) {
ret = -ERESTARTSYS;
goto out_rpm;
}
/* Must be in offline mode already */
if (!usb4->offline) {
ret = -EINVAL;
goto out_unlock;
}
tb_retimer_remove_all(port);
ret = tb_retimer_scan(port, true);
out_unlock:
mutex_unlock(&tb->lock);
out_rpm:
pm_runtime_mark_last_busy(&usb4->dev);
pm_runtime_put_autosuspend(&usb4->dev);
return ret ? ret : count;
}
static DEVICE_ATTR_WO(rescan);
static struct attribute *service_attrs[] = {
&dev_attr_offline.attr,
&dev_attr_rescan.attr,
NULL
};
static umode_t service_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb4_port *usb4 = tb_to_usb4_port_device(dev);
/*
* Always need some platform help to cycle the modes so that
* retimers can be accessed through the sideband.
*/
return usb4->can_offline ? attr->mode : 0;
}
static const struct attribute_group service_group = {
.attrs = service_attrs,
.is_visible = service_attr_is_visible,
};
static const struct attribute_group *usb4_port_device_groups[] = {
&common_group,
&service_group,
NULL
};
static void usb4_port_device_release(struct device *dev)
{
struct usb4_port *usb4 = container_of(dev, struct usb4_port, dev);
kfree(usb4);
}
struct device_type usb4_port_device_type = {
.name = "usb4_port",
.groups = usb4_port_device_groups,
.release = usb4_port_device_release,
};
/**
* usb4_port_device_add() - Add USB4 port device
* @port: Lane 0 adapter port to add the USB4 port
*
* Creates and registers a USB4 port device for @port. Returns the new
* USB4 port device pointer or ERR_PTR() in case of error.
*/
struct usb4_port *usb4_port_device_add(struct tb_port *port)
{
struct usb4_port *usb4;
int ret;
usb4 = kzalloc(sizeof(*usb4), GFP_KERNEL);
if (!usb4)
return ERR_PTR(-ENOMEM);
usb4->port = port;
usb4->dev.type = &usb4_port_device_type;
usb4->dev.parent = &port->sw->dev;
dev_set_name(&usb4->dev, "usb4_port%d", port->port);
ret = device_register(&usb4->dev);
if (ret) {
put_device(&usb4->dev);
return ERR_PTR(ret);
}
if (dev_fwnode(&usb4->dev)) {
ret = component_add(&usb4->dev, &connector_ops);
if (ret) {
dev_err(&usb4->dev, "failed to add component\n");
device_unregister(&usb4->dev);
}
}
pm_runtime_no_callbacks(&usb4->dev);
pm_runtime_set_active(&usb4->dev);
pm_runtime_enable(&usb4->dev);
pm_runtime_set_autosuspend_delay(&usb4->dev, TB_AUTOSUSPEND_DELAY);
pm_runtime_mark_last_busy(&usb4->dev);
pm_runtime_use_autosuspend(&usb4->dev);
return usb4;
}
/**
* usb4_port_device_remove() - Removes USB4 port device
* @usb4: USB4 port device
*
* Unregisters the USB4 port device from the system. The device will be
* released when the last reference is dropped.
*/
void usb4_port_device_remove(struct usb4_port *usb4)
{
if (dev_fwnode(&usb4->dev))
component_del(&usb4->dev, &connector_ops);
device_unregister(&usb4->dev);
}
/**
* usb4_port_device_resume() - Resumes USB4 port device
* @usb4: USB4 port device
*
* Used to resume USB4 port device after sleep state.
*/
int usb4_port_device_resume(struct usb4_port *usb4)
{
return usb4->offline ? usb4_port_offline(usb4) : 0;
}