From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753738AbaHDREX (ORCPT ); Mon, 4 Aug 2014 13:04:23 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:56542 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751949AbaHDQt4 (ORCPT ); Mon, 4 Aug 2014 12:49:56 -0400 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, "Alan Stern" , "Greg Kroah-Hartman" , "Gavin Guo" Date: Mon, 04 Aug 2014 17:48:32 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 54/94] usb: Check if port status is equal to RxDetect In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Gavin Guo commit bb86cf569bbd7ad4dce581a37c7fbd748057e9dc upstream. When using USB 3.0 pen drive with the [AMD] FCH USB XHCI Controller [1022:7814], the second hotplugging will experience the USB 3.0 pen drive is recognized as high-speed device. After bisecting the kernel, I found the commit number 41e7e056cdc662f704fa9262e5c6e213b4ab45dd (USB: Allow USB 3.0 ports to be disabled.) causes the bug. After doing some experiments, the bug can be fixed by avoiding executing the function hub_usb3_port_disable(). Because the port status with [AMD] FCH USB XHCI Controlleris [1022:7814] is already in RxDetect (I tried printing out the port status before setting to Disabled state), it's reasonable to check the port status before really executing hub_usb3_port_disable(). Fixes: 41e7e056cdc6 (USB: Allow USB 3.0 ports to be disabled.) Signed-off-by: Gavin Guo Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: use hub device as context for dev_dbg(), as hub ports are not devices in their own right] Signed-off-by: Ben Hutchings --- drivers/usb/core/hub.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -655,6 +655,26 @@ static int hub_usb3_port_disable(struct if (!hub_is_superspeed(hub->hdev)) return -EINVAL; + ret = hub_port_status(hub, port1, &portstatus, &portchange); + if (ret < 0) + return ret; + + /* + * USB controller Advanced Micro Devices, Inc. [AMD] FCH USB XHCI + * Controller [1022:7814] will have spurious result making the following + * usb 3.0 device hotplugging route to the 2.0 root hub and recognized + * as high-speed device if we set the usb 3.0 port link state to + * Disabled. Since it's already in USB_SS_PORT_LS_RX_DETECT state, we + * check the state here to avoid the bug. + */ + if ((portstatus & USB_PORT_STAT_LINK_STATE) == + USB_SS_PORT_LS_RX_DETECT) { + dev_dbg(hub->intfdev, + "Not disabling port %d; link state is RxDetect\n", + port1); + return ret; + } + ret = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_SS_DISABLED); if (ret) { dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",