xhci: Check all endpoints for LPM timeout

BugLink: https://bugs.launchpad.net/bugs/1848780

commit d500c63f upstream.

If an endpoint is encountered that returns USB3_LPM_DEVICE_INITIATED, keep
checking further endpoints, as there might be periodic endpoints later
that return USB3_LPM_DISABLED due to shorter service intervals.

Without this, the code can set too high a maximum-exit-latency and
prevent the use of multiple USB3 cameras that should be able to work.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Schmidt <jan@centricular.com>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1570190373-30684-4-git-send-email-mathias.nyman@linux.intel.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/usb/host/xhci.c

@@ -4535,12 +4535,12 @@ static int xhci_update_timeout_for_endpoint(struct xhci_hcd *xhci,
 	alt_timeout = xhci_call_host_update_timeout_for_endpoint(xhci, udev,
 		desc, state, timeout);
 
-	/* If we found we can't enable hub-initiated LPM, or
+	/* If we found we can't enable hub-initiated LPM, and
 	 * the U1 or U2 exit latency was too high to allow
-	 * device-initiated LPM as well, just stop searching.
+	 * device-initiated LPM as well, then we will disable LPM
+	 * for this device, so stop searching any further.
 	 */
-	if (alt_timeout == USB3_LPM_DISABLED ||
-			alt_timeout == USB3_LPM_DEVICE_INITIATED) {
+	if (alt_timeout == USB3_LPM_DISABLED) {
 		*timeout = alt_timeout;
 		return -E2BIG;
 	}