• Alan Stern's avatar
    USB: add NO_D3_DURING_SLEEP flag and revert 151b6128 · c2fb8a3f
    Alan Stern authored
    This patch (as1558) fixes a problem affecting several ASUS computers:
    The machine crashes or corrupts memory when going into suspend if the
    ehci-hcd driver is bound to any controllers.  Users have been forced
    to unbind or unload ehci-hcd before putting their systems to sleep.
    
    After extensive testing, it was determined that the machines don't
    like going into suspend when any EHCI controllers are in the PCI D3
    power state.  Presumably this is a firmware bug, but there's nothing
    we can do about it except to avoid putting the controllers in D3
    during system sleep.
    
    The patch adds a new flag to indicate whether the problem is present,
    and avoids changing the controller's power state if the flag is set.
    Runtime suspend is unaffected; this matters only for system suspend.
    However as a side effect, the controller will not respond to remote
    wakeup requests while the system is asleep.  Hence USB wakeup is not
    functional -- but of course, this is already true in the current state
    of affairs.
    
    A similar patch has already been applied as commit
    151b6128 (USB: EHCI: fix crash during
    suspend on ASUS computers).  The patch supersedes that one and reverts
    it.  There are two differences:
    
    	The old patch added the flag at the USB level; this patch
    	adds it at the PCI level.
    
    	The old patch applied to all chipsets with the same vendor,
    	subsystem vendor, and product IDs; this patch makes an
    	exception for a known-good system (based on DMI information).
    Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
    Tested-by: default avatarDâniel Fraga <fragabr@gmail.com>
    Tested-by: default avatarAndrey Rahmatullin <wrar@wrar.name>
    Tested-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    Cc: stable <stable@vger.kernel.org>
    Reviewed-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    c2fb8a3f
ehci-pci.c 15.9 KB