From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7B82C169C4 for ; Sun, 3 Feb 2019 13:55:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 802A1218D8 for ; Sun, 3 Feb 2019 13:55:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729103AbfBCNyq (ORCPT ); Sun, 3 Feb 2019 08:54:46 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54470 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728595AbfBCNym (ORCPT ); Sun, 3 Feb 2019 08:54:42 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqIEK-0003te-8x; Sun, 03 Feb 2019 13:54:40 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqI9r-0007Oo-Im; Sun, 03 Feb 2019 14:50:03 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Greg Kroah-Hartman" , "Mathias Nyman" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 269/305] xhci: Prevent U1/U2 link pm states if exit latency is too long In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mathias Nyman commit 0472bf06c6fd33c1a18aaead4c8f91e5a03d8d7b upstream. Don't allow USB3 U1 or U2 if the latency to wake up from the U-state reaches the service interval for a periodic endpoint. This is according to xhci 1.1 specification section 4.23.5.2 extra note: "Software shall ensure that a device is prevented from entering a U-state where its worst case exit latency approaches the ESIT." Allowing too long exit latencies for periodic endpoint confuses xHC internal scheduling, and new devices may fail to enumerate with a "Not enough bandwidth for new device state" error from the host. Signed-off-by: Mathias Nyman Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.16: adjust context, indentation] Signed-off-by: Ben Hutchings --- drivers/usb/host/xhci.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4466,9 +4466,25 @@ static u16 xhci_call_host_update_timeout u16 *timeout) { if (state == USB3_LPM_U1) { + /* Prevent U1 if service interval is shorter than U1 exit latency */ + if (usb_endpoint_xfer_int(desc) || usb_endpoint_xfer_isoc(desc)) { + if (xhci_service_interval_to_ns(desc) <= udev->u1_params.mel) { + dev_dbg(&udev->dev, "Disable U1, ESIT shorter than exit latency\n"); + return USB3_LPM_DISABLED; + } + } + if (xhci->quirks & XHCI_INTEL_HOST) return xhci_calculate_intel_u1_timeout(udev, desc); } else { + /* Prevent U2 if service interval is shorter than U2 exit latency */ + if (usb_endpoint_xfer_int(desc) || usb_endpoint_xfer_isoc(desc)) { + if (xhci_service_interval_to_ns(desc) <= udev->u2_params.mel) { + dev_dbg(&udev->dev, "Disable U2, ESIT shorter than exit latency\n"); + return USB3_LPM_DISABLED; + } + } + if (xhci->quirks & XHCI_INTEL_HOST) return xhci_calculate_intel_u2_timeout(udev, desc); }