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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 E8213C0044C for ; Wed, 31 Oct 2018 05:52:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8CA220657 for ; Wed, 31 Oct 2018 05:52:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B8CA220657 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=canonical.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729006AbeJaOsy (ORCPT ); Wed, 31 Oct 2018 10:48:54 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42318 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727958AbeJaOsy (ORCPT ); Wed, 31 Oct 2018 10:48:54 -0400 Received: from 61-220-137-37.hinet-ip.hinet.net ([61.220.137.37] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1gHjQN-0001wI-JW; Wed, 31 Oct 2018 05:52:16 +0000 From: Kai-Heng Feng To: gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Kai-Heng Feng Subject: [PATCH v2] USB: Don't enable LPM if it's already enabled Date: Wed, 31 Oct 2018 13:52:09 +0800 Message-Id: <20181031055209.11031-1-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org USB Bluetooth controller QCA ROME (0cf3:e007) sometimes stops working after S3: [ 165.110742] Bluetooth: hci0: using NVM file: qca/nvm_usb_00000302.bin [ 168.432065] Bluetooth: hci0: Failed to send body at 4 of 1953 (-110) After some experiments, I found that disabling LPM can workaround the issue. On some platforms, the USB power is cut during S3, so the driver uses reset-resume to resume the device. During port resume, LPM gets enabled twice, by usb_reset_and_verify_device() and usb_port_resume(). So let's enable LPM for just once, as this solves the issue for the device in question. Signed-off-by: Kai-Heng Feng --- v2: - Check udev->usb2_hw_lpm_enabled before calling usb_port_resume(). drivers/usb/core/hub.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index c6077d582d29..02fa574e98ce 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3523,7 +3523,8 @@ int usb_port_resume(struct usb_device *udev, pm_message_t msg) hub_port_logical_disconnect(hub, port1); } else { /* Try to enable USB2 hardware LPM */ - if (udev->usb2_hw_lpm_capable == 1) + if (udev->usb2_hw_lpm_capable == 1 && + !udev->usb2_hw_lpm_enabled) usb_set_usb2_hardware_lpm(udev, 1); /* Try to enable USB3 LTM */ -- 2.19.1