From: Jan-Marek Glogowski <glo...@fbihome.de>

[ 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 <glo...@fbihome.de>
Acked-by: Alan Stern <st...@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
 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 b543a4730ef24..bb20aa433e984 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -104,6 +104,8 @@ 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)
 {
@@ -1110,6 +1112,11 @@ 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

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