PM: USB HCDs use PM_EVENT_PRETHAW

This teaches several USB host controller drivers to treat PRETHAW as a chip
reset since the controller, and all devices connected to it, are no longer in
states compatible with how the snapshotted suspend() left them.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index cadffacd945b..6967ab71e282 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -238,6 +238,12 @@ static int ehci_pci_suspend(struct usb_hcd *hcd, pm_message_t message)
         writel (0, &ehci->regs->intr_enable);
         (void)readl(&ehci->regs->intr_enable);
 
+        /* make sure snapshot being resumed re-enumerates everything */
+        if (message.event == PM_EVENT_PRETHAW) {
+                ehci_halt(ehci);
+                ehci_reset(ehci);
+        }
+
         clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
  bail:
         spin_unlock_irqrestore (&ehci->lock, flags);