Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965489AbaDJD6D (ORCPT ); Wed, 9 Apr 2014 23:58:03 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41175 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934917AbaDJDWg (ORCPT ); Wed, 9 Apr 2014 23:22:36 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Julius Werner , Alan Stern , Ben Hutchings , Yang Yingliang Subject: [PATCH 3.4 096/134] usb: hub: Clear Port Reset Change during init/resume Date: Wed, 9 Apr 2014 20:23:32 -0700 Message-Id: <20140410032312.031855798@linuxfoundation.org> X-Mailer: git-send-email 1.9.0 In-Reply-To: <20140410032259.587501440@linuxfoundation.org> References: <20140410032259.587501440@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Julius Werner commit e92aee330837e4911553761490a8fb843f2053a6 upstream. This patch adds the Port Reset Change flag to the set of bits that are preemptively cleared on init/resume of a hub. In theory this bit should never be set unexpectedly... in practice it can still happen if BIOS, SMM or ACPI code plays around with USB devices without cleaning up correctly. This is especially dangerous for XHCI root hubs, which don't generate any more Port Status Change Events until all change bits are cleared, so this is a good precaution to have (similar to how it's already done for the Warm Port Reset Change flag). Signed-off-by: Julius Werner Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: - Adjust context - s/usb_clear_port_feature/clear_port_feature/] Signed-off-by: Ben Hutchings [yangyl: Backported to 3.4: Adjust context] Signed-off-by: Yang Yingliang Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/hub.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -920,6 +920,11 @@ static void hub_activate(struct usb_hub clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_ENABLE); } + if (portchange & USB_PORT_STAT_C_RESET) { + need_debounce_delay = true; + clear_port_feature(hub->hdev, port1, + USB_PORT_FEAT_C_RESET); + } if ((portchange & USB_PORT_STAT_C_BH_RESET) && hub_is_superspeed(hub->hdev)) { need_debounce_delay = true; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/