Commit 961ba81d authored Feb 01, 2019 by Jan-Marek Glogowski Committed by Greg Kroah-Hartman Nov 06, 2019

usb: handle warm-reset port requests on hub resume



[ 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@fbihome.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 3a77562e

drivers/usb/core/hub.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -107,6 +107,8 @@ 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)
		{
		@@ -1111,6 +1113,11 @@ 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