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usb: handle warm-reset port requests on hub resume 

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>
This commit is contained in:
Jan-Marek Glogowski 2019-02-01 13:52:31 +01:00 committed by Greg Kroah-Hartman
parent 68f1ec8ea1
commit 4fdc1790e6
1 changed files with 7 additions and 0 deletions
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7
drivers/usb/core/hub.c
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@ -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