Commit 61fbeba1 authored Oct 27, 2008 by Alan Stern Committed by Greg Kroah-Hartman Oct 29, 2008

USB: prevent autosuspend during hub initialization



This patch (as1153) fixes a potential problem in hub initialization.
Starting in 2.6.28, initialization was split into several tasks to
help speed up booting.  This opens the possibility that the hub may be
autosuspended before all the initialization tasks can complete.

Normally that wouldn't matter, but with incomplete initialization
there is a risk that the hub would never autoresume -- especially if
devices were plugged into the hub beforehand.  The solution is a
simple one-line change to suppress autosuspend until the
initialization is finished.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 74511bb3

drivers/usb/core/hub.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -659,6 +659,9 @@ static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
		PREPARE_DELAYED_WORK(&hub->init_work, hub_init_func2);
		schedule_delayed_work(&hub->init_work,
		msecs_to_jiffies(delay));

		/* Suppress autosuspend until init is done */
		to_usb_interface(hub->intfdev)->pm_usage_cnt = 1;
		return; /* Continues at init2: below */
		} else {
		hub_power_on(hub, true);

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