@@ -96,6 +96,7 @@ struct usb_hub {
* @usb3_lpm_u2_permit: whether USB3 U2 LPM is permitted.
* @early_stop: whether port initialization will be stopped earlier.
* @ignore_event: whether events of the port are ignored.
+ * @disabled: whether the port is disabled
*/
struct usb_port {
struct usb_device *child;
@@ -117,6 +118,7 @@ struct usb_port {
unsigned int is_superspeed:1;
unsigned int usb3_lpm_u1_permit:1;
unsigned int usb3_lpm_u2_permit:1;
+ unsigned int disabled:1;
};
#define to_usb_port(_dev) \
@@ -117,6 +117,10 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
if (rc)
return rc;
+ /* Early quit if no change was detected */
+ if (port_dev->disabled == disabled)
+ return count;
+
hub_get(hub);
rc = usb_autopm_get_interface(intf);
if (rc < 0)
@@ -148,6 +152,8 @@ static ssize_t disable_store(struct device *dev, struct device_attribute *attr,
usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
}
+ port_dev->disabled = disabled;
+
if (!rc)
rc = count;
The disable state isn't tracked at the moment, instead the state is directly passed to the hub driver. Change this behavior to only trigger the hub if a state change happened. Exit early in case of no state changes but don't return an error. Signed-off-by: Marco Felsch <m.felsch@pengutronix.de> --- drivers/usb/core/hub.h | 2 ++ drivers/usb/core/port.c | 6 ++++++ 2 files changed, 8 insertions(+)