From d500c63f80f2ea08ee300e57da5f2af1c13875f5 Mon Sep 17 00:00:00 2001
From: Jan Schmidt <jan@centricular.com>
Date: Fri, 4 Oct 2019 14:59:28 +0300
Subject: [PATCH] xhci: Check all endpoints for LPM timeout
Git-commit: d500c63f80f2ea08ee300e57da5f2af1c13875f5
Patch-mainline: v5.4-rc3
References: bsc#1051510

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.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/host/xhci.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index aed5a65f25bd..a5ba5ace3d00 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4674,12 +4674,12 @@ 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;
 	}
-- 
2.16.4