From: Dennis Wassenberg Date: Tue, 13 Nov 2018 13:40:34 +0000 (+0100) Subject: usb: core: Fix hub port connection events lost X-Git-Tag: v4.20-rc4~19^2~2 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=22454b79e6de05fa61a2a72d00d2eed798abbb75;p=uclinux-h8%2Flinux.git usb: core: Fix hub port connection events lost This will clear the USB_PORT_FEAT_C_CONNECTION bit in case of a hub port reset only if a device is was attached to the hub port before resetting the hub port. Using a Lenovo T480s attached to the ultra dock it was not possible to detect some usb-c devices at the dock usb-c ports because the hub_port_reset code will clear the USB_PORT_FEAT_C_CONNECTION bit after the actual hub port reset. Using this device combo the USB_PORT_FEAT_C_CONNECTION bit was set between the actual hub port reset and the clear of the USB_PORT_FEAT_C_CONNECTION bit. This ends up with clearing the USB_PORT_FEAT_C_CONNECTION bit after the new device was attached such that it was not detected. This patch will not clear the USB_PORT_FEAT_C_CONNECTION bit if there is currently no device attached to the port before the hub port reset. This will avoid clearing the connection bit for new attached devices. Signed-off-by: Dennis Wassenberg Acked-by: Mathias Nyman Cc: stable Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index d9bd7576786a..0f9381b69a3b 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -2850,7 +2850,9 @@ static int hub_port_reset(struct usb_hub *hub, int port1, USB_PORT_FEAT_C_BH_PORT_RESET); usb_clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_PORT_LINK_STATE); - usb_clear_port_feature(hub->hdev, port1, + + if (udev) + usb_clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_CONNECTION); /*