From: Jan-Marek Glogowski <glogow@xxxxxxxxxx> [ Upstream commit 4fdc1790e6a9ef22399c6bc6e63b80f4609f3b7e ] On plug-in of my USB-C device, its USB_SS_PORT_LS_SS_INACTIVE link state bit is set. Greping all the kernel for this bit shows that the port status requests a warm-reset this way. This just happens, if its the only device on the root hub, the hub therefore resumes and the HCDs status_urb isn't yet available. If a warm-reset request is detected, this sets the hubs event_bits, which will prevent any auto-suspend and allows the hubs workqueue to warm-reset the port later in port_event. Signed-off-by: Jan-Marek Glogowski <glogow@xxxxxxxxxx> Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/usb/core/hub.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 63646dc3ca27d..4a87cc4783404 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -102,6 +102,8 @@ EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem); static void hub_release(struct kref *kref); static int usb_reset_and_verify_device(struct usb_device *udev); static int hub_port_disable(struct usb_hub *hub, int port1, int set_state); +static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1, + u16 portstatus); static inline char *portspeed(struct usb_hub *hub, int portstatus) { @@ -1108,6 +1110,11 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type) USB_PORT_FEAT_ENABLE); } + /* Make sure a warm-reset request is handled by port_event */ + if (type == HUB_RESUME && + hub_port_warm_reset_required(hub, port1, portstatus)) + set_bit(port1, hub->event_bits); + /* * Add debounce if USB3 link is in polling/link training state. * Link will automatically transition to Enabled state after -- 2.20.1