USB: add quirk for devices with broken LPM
Some USB device / host controller combinations seem to have problems
with Link Power Management. For example, Steinar found that his xHCI
controller wouldn't handle bandwidth calculations correctly for two
video cards simultaneously when LPM was enabled, even though the bus
had plenty of bandwidth available.
This patch introduces a new quirk flag for devices that should remain
disabled for LPM, and creates quirk entries for Steinar's devices.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Steinar H. Gunderson <sgunderson@bigfoot.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/usb/quirks.h b/include/linux/usb/quirks.h
index 9948c87..1d0043d 100644
--- a/include/linux/usb/quirks.h
+++ b/include/linux/usb/quirks.h
@@ -47,4 +47,7 @@
/* device generates spurious wakeup, ignore remote wakeup capability */
#define USB_QUIRK_IGNORE_REMOTE_WAKEUP BIT(9)
+/* device can't handle Link Power Management */
+#define USB_QUIRK_NO_LPM BIT(10)
+
#endif /* __LINUX_USB_QUIRKS_H */