usb: handle warm-reset port requests on hub resume (4fdc1790) · Commits · 戴 / test

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@fbihome.de> Acked-by:

Alan Stern <stern@rowland.harvard.edu> Signed-off-by:

Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hub.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -108,6 +108,8 @@ 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)
		{
		@@ -1137,6 +1139,11 @@ 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

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