USB: EHCI: ASPM quirk of ISOC on AMD SB800

When ASPM PM Feature is enabled on UMI link, devices that use ISOC stream of
data transfer may be exposed to longer latency causing less than optimal per-
formance of the device. The longer latencies are normal and are due to link
wake time coming out of low power state which happens frequently to save
power when the link is not active.
The following code will make exception for certain features of ASPM to be by
passed and keep the logic normal state only when the ISOC device is connected
and active. This change will allow the device to run at optimal performance
yet minimize the impact on overall power savings.

Signed-off-by: Alex He <alex.he@amd.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index bde823f704e9..fd1c53da89e4 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -130,6 +130,7 @@ struct ehci_hcd {			/* one per controller */
         unsigned                has_amcc_usb23:1;
         unsigned                need_io_watchdog:1;
         unsigned                broken_periodic:1;
+        unsigned                amd_l1_fix:1;
         unsigned                fs_i_thresh:1;  /* Intel iso scheduling */
 
         /* required for usb32 quirk */