From patchwork Wed Nov 6 06:27:10 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 11229367 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AA4D213BD for ; Wed, 6 Nov 2019 06:27:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7BB52206DF for ; Wed, 6 Nov 2019 06:27:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729922AbfKFG1V (ORCPT ); Wed, 6 Nov 2019 01:27:21 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44398 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728112AbfKFG1V (ORCPT ); Wed, 6 Nov 2019 01:27:21 -0500 Received: from 61-220-137-37.hinet-ip.hinet.net ([61.220.137.37] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1iSEmj-0004kO-6K; Wed, 06 Nov 2019 06:27:17 +0000 From: Kai-Heng Feng To: gregkh@linuxfoundation.org Cc: mathias.nyman@intel.com, stern@rowland.harvard.edu, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Kai-Heng Feng Subject: [PATCH v2] usb: Allow USB device to be warm reset in suspended state Date: Wed, 6 Nov 2019 14:27:10 +0800 Message-Id: <20191106062710.29880-1-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.17.1 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Dell WD15 dock, sometimes USB ethernet cannot be detected after plugging cable to the ethernet port, the hub and roothub get runtime resumed and runtime suspended immediately: ... [ 433.315169] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_resume: 0 [ 433.315204] usb usb4: usb auto-resume [ 433.315226] hub 4-0:1.0: hub_resume [ 433.315239] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10202e2, return 0x10343 [ 433.315264] usb usb4-port1: status 0343 change 0001 [ 433.315279] xhci_hcd 0000:3a:00.0: clear port1 connect change, portsc: 0x10002e2 [ 433.315293] xhci_hcd 0000:3a:00.0: Get port status 4-2 read: 0x2a0, return 0x2a0 [ 433.317012] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.422282] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10002e2, return 0x343 [ 433.422307] usb usb4-port1: do warm reset [ 433.422311] usb 4-1: device reset not allowed in state 8 [ 433.422339] hub 4-0:1.0: state 7 ports 2 chg 0002 evt 0000 [ 433.422346] xhci_hcd 0000:3a:00.0: Get port status 4-1 read: 0x10002e2, return 0x343 [ 433.422356] usb usb4-port1: do warm reset [ 433.422358] usb 4-1: device reset not allowed in state 8 [ 433.422428] xhci_hcd 0000:3a:00.0: set port remote wake mask, actual port 0 status = 0xf0002e2 [ 433.422455] xhci_hcd 0000:3a:00.0: set port remote wake mask, actual port 1 status = 0xe0002a0 [ 433.422465] hub 4-0:1.0: hub_suspend [ 433.422475] usb usb4: bus auto-suspend, wakeup 1 [ 433.426161] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.466209] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.510204] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.554051] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.598235] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.642154] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.686204] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.730205] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.774203] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.818207] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.862040] xhci_hcd 0000:3a:00.0: port 0 polling in bus suspend, waiting [ 433.862053] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.862077] xhci_hcd 0000:3a:00.0: xhci_suspend: stopping port polling. [ 433.862096] xhci_hcd 0000:3a:00.0: // Setting command ring address to 0x8578fc001 [ 433.862312] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_suspend: 0 [ 433.862445] xhci_hcd 0000:3a:00.0: PME# enabled [ 433.902376] xhci_hcd 0000:3a:00.0: restoring config space at offset 0xc (was 0x0, writing 0x20) [ 433.902395] xhci_hcd 0000:3a:00.0: restoring config space at offset 0x4 (was 0x100000, writing 0x100403) [ 433.902490] xhci_hcd 0000:3a:00.0: PME# disabled [ 433.902504] xhci_hcd 0000:3a:00.0: enabling bus mastering [ 433.902547] xhci_hcd 0000:3a:00.0: // Setting command ring address to 0x8578fc001 [ 433.902649] pcieport 0000:00:1b.0: PME: Spurious native interrupt! [ 433.902839] xhci_hcd 0000:3a:00.0: Port change event, 4-1, id 3, portsc: 0xb0202e2 [ 433.902842] xhci_hcd 0000:3a:00.0: resume root hub [ 433.902845] xhci_hcd 0000:3a:00.0: handle_port_status: starting port polling. [ 433.902877] xhci_hcd 0000:3a:00.0: xhci_resume: starting port polling. [ 433.902889] xhci_hcd 0000:3a:00.0: xhci_hub_status_data: stopping port polling. [ 433.902891] xhci_hcd 0000:3a:00.0: hcd_pci_runtime_resume: 0 [ 433.902919] usb usb4: usb wakeup-resume [ 433.902942] usb usb4: usb auto-resume [ 433.902966] hub 4-0:1.0: hub_resume ... As Mathias pointed out, the hub enters Cold Attach Status state and requires a warm reset. However usb_reset_device() bails out early when the device is in suspended state, as its callers port_event() and hub_event() don't always resume the device. Since there's nothing wrong to reset a suspended device, allow usb_reset_device() to do so to solve the issue. Signed-off-by: Kai-Heng Feng Acked-by: Alan Stern --- v2: - Update kerneldoc. drivers/usb/core/hub.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 05a2d51bdbe0..eaf28eed51b0 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -5849,7 +5849,7 @@ static int usb_reset_and_verify_device(struct usb_device *udev) /** * usb_reset_device - warn interface drivers and perform a USB port reset - * @udev: device to reset (not in SUSPENDED or NOTATTACHED state) + * @udev: device to reset (not in NOTATTACHED state) * * Warns all drivers bound to registered interfaces (using their pre_reset * method), performs the port reset, and then lets the drivers know that @@ -5877,8 +5877,7 @@ int usb_reset_device(struct usb_device *udev) struct usb_host_config *config = udev->actconfig; struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent); - if (udev->state == USB_STATE_NOTATTACHED || - udev->state == USB_STATE_SUSPENDED) { + if (udev->state == USB_STATE_NOTATTACHED) { dev_dbg(&udev->dev, "device reset not allowed in state %d\n", udev->state); return -EINVAL;