@@ -292,6 +292,16 @@ Description:
which is marked with early_stop has failed to initialize, it will ignore
all future connections until this attribute is clear.
+What: /sys/bus/usb/devices/.../<hub_interface>/port<X>/state
+Date: June 2023
+Contact: Roy Luo <royluo@google.com>
+Description:
+ Indicates current state of the USB device attached to the port.
+ Valid states are: 'not-attached', 'attached', 'powered',
+ 'reconnecting', 'unauthenticated', 'default', 'addressed',
+ 'configured', and 'suspended'. This file supports poll() to
+ monitor the state change from user space.
+
What: /sys/bus/usb/devices/.../power/usb2_lpm_l1_timeout
Date: May 2013
Contact: Mathias Nyman <mathias.nyman@linux.intel.com>
@@ -2018,6 +2018,19 @@ bool usb_device_is_owned(struct usb_device *udev)
return !!hub->ports[udev->portnum - 1]->port_owner;
}
+static void update_port_device_state(struct usb_device *udev)
+{
+ struct usb_hub *hub;
+ struct usb_port *port_dev;
+
+ if (udev->parent) {
+ hub = usb_hub_to_struct_hub(udev->parent);
+ port_dev = hub->ports[udev->portnum - 1];
+ WRITE_ONCE(port_dev->state, udev->state);
+ sysfs_notify_dirent(port_dev->state_kn);
+ }
+}
+
static void recursively_mark_NOTATTACHED(struct usb_device *udev)
{
struct usb_hub *hub = usb_hub_to_struct_hub(udev);
@@ -2030,6 +2043,7 @@ static void recursively_mark_NOTATTACHED(struct usb_device *udev)
if (udev->state == USB_STATE_SUSPENDED)
udev->active_duration -= jiffies;
udev->state = USB_STATE_NOTATTACHED;
+ update_port_device_state(udev);
}
/**
@@ -2086,6 +2100,7 @@ void usb_set_device_state(struct usb_device *udev,
udev->state != USB_STATE_SUSPENDED)
udev->active_duration += jiffies;
udev->state = new_state;
+ update_port_device_state(udev);
} else
recursively_mark_NOTATTACHED(udev);
spin_unlock_irqrestore(&device_state_lock, flags);
@@ -84,6 +84,8 @@ struct usb_hub {
* @peer: related usb2 and usb3 ports (share the same connector)
* @req: default pm qos request for hubs without port power control
* @connect_type: port's connect type
+ * @state: device state of the usb device attached to the port
+ * @state_kn: kernfs_node of the sysfs attribute that accesses @state
* @location: opaque representation of platform connector location
* @status_lock: synchronize port_event() vs usb_port_{suspend|resume}
* @portnum: port index num based one
@@ -100,6 +102,8 @@ struct usb_port {
struct usb_port *peer;
struct dev_pm_qos_request *req;
enum usb_port_connect_type connect_type;
+ enum usb_device_state state;
+ struct kernfs_node *state_kn;
usb_port_location_t location;
struct mutex status_lock;
u32 over_current_count;
@@ -160,6 +160,16 @@ static ssize_t connect_type_show(struct device *dev,
}
static DEVICE_ATTR_RO(connect_type);
+static ssize_t state_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_port *port_dev = to_usb_port(dev);
+ enum usb_device_state state = READ_ONCE(port_dev->state);
+
+ return sysfs_emit(buf, "%s\n", usb_state_string(state));
+}
+static DEVICE_ATTR_RO(state);
+
static ssize_t over_current_count_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -259,6 +269,7 @@ static DEVICE_ATTR_RW(usb3_lpm_permit);
static struct attribute *port_dev_attrs[] = {
&dev_attr_connect_type.attr,
+ &dev_attr_state.attr,
&dev_attr_location.attr,
&dev_attr_quirks.attr,
&dev_attr_over_current_count.attr,
@@ -705,19 +716,24 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
return retval;
}
+ port_dev->state_kn = sysfs_get_dirent(port_dev->dev.kobj.sd, "state");
+ if (!port_dev->state_kn) {
+ dev_err(&port_dev->dev, "failed to sysfs_get_dirent 'state'\n");
+ retval = -ENODEV;
+ goto err_unregister;
+ }
+
/* Set default policy of port-poweroff disabled. */
retval = dev_pm_qos_add_request(&port_dev->dev, port_dev->req,
DEV_PM_QOS_FLAGS, PM_QOS_FLAG_NO_POWER_OFF);
if (retval < 0) {
- device_unregister(&port_dev->dev);
- return retval;
+ goto err_put_kn;
}
retval = component_add(&port_dev->dev, &connector_ops);
if (retval) {
dev_warn(&port_dev->dev, "failed to add component\n");
- device_unregister(&port_dev->dev);
- return retval;
+ goto err_put_kn;
}
find_and_link_peer(hub, port1);
@@ -754,6 +770,13 @@ int usb_hub_create_port_device(struct usb_hub *hub, int port1)
port_dev->req = NULL;
}
return 0;
+
+err_put_kn:
+ sysfs_put(port_dev->state_kn);
+err_unregister:
+ device_unregister(&port_dev->dev);
+
+ return retval;
}
void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
@@ -765,5 +788,6 @@ void usb_hub_remove_port_device(struct usb_hub *hub, int port1)
if (peer)
unlink_peers(port_dev, peer);
component_del(&port_dev->dev, &connector_ops);
+ sysfs_put(port_dev->state_kn);
device_unregister(&port_dev->dev);
}