From patchwork Tue Feb 4 17:52:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lauri Jakku X-Patchwork-Id: 11365109 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 202DF1395 for ; Tue, 4 Feb 2020 17:54:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 090E92087E for ; Tue, 4 Feb 2020 17:54:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727392AbgBDRyD (ORCPT ); Tue, 4 Feb 2020 12:54:03 -0500 Received: from mta-out1.inet.fi ([62.71.2.202]:33196 "EHLO johanna1.inet.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727359AbgBDRyD (ORCPT ); Tue, 4 Feb 2020 12:54:03 -0500 Received: from MinistryOfSillyWalk.home (84.248.30.195) by johanna1.inet.fi (9.0.019.26-1) id 5E1C39AA16353BBB; Tue, 4 Feb 2020 19:53:52 +0200 From: Lauri Jakku To: oneukum@suse.com, benjamin.tissoires@redhat.com Cc: jikos@kernel.org, linux-input@vger.kernel.org, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, Lauri Jakku Subject: [PATCH v5] USB: HID: random timeout failures tackle try. Date: Tue, 4 Feb 2020 19:52:39 +0200 Message-Id: <20200204175238.3817-1-lja@iki.fi> X-Mailer: git-send-email 2.25.0 MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org -- v1 ------------------------------------------------------------ send, 20ms apart, control messages, if error is timeout. There is multiple reports of random behaviour of USB HID devices. I have mouse that acts sometimes quite randomly, I debugged with logs others have published that there is HW timeouts that leave device in state that it is errorneus. To fix this I introduced retry mechanism in root of USB HID drivers. Fix does not slow down operations at all if there is no -ETIMEDOUT got from control message sending. If there is one, then sleep 20ms and try again. Retry count is 20 witch translates maximium of 400ms before giving up. NOTE: This does not sleep anymore then before, if all is golden. -- v2 ------------------------------------------------------------ If there is timeout, then sleep 20ms and try again. Retry count is 20 witch translates maximium of 400ms before giving up. If the 400ms boundary is reached the HW is really bad. JUST to be clear: This does not make USB HID devices to sleep anymore than before, if all is golden. Why modify usb-hid-core: No need to modify driver by driver. -- v3 ------------------------------------------------------------ Timeout given is divided by 100, but taken care that it is always at least 10ms. so total time in common worst-case-scenario is: sleep of 20ms + common timeout divided by 100 (50ms) makes 70ms per loop, 20 loops => 1.4sec . -- v4 ------------------------------------------------------------ No changes in code, just elaborating what is done in v[1,2,3]. -- v5 ------------------------------------------------------------ changes in code: what the build robot found: drivers/usb/core/message.c: In function 'usb_control_msg': >> drivers/usb/core/message.c:173:11: error: type defaults to 'int' \ in declaration of 'timeout_happened' [-Werror=implicit-int] static timeout_happened = 0; ^~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors Fix done: added int to declaration. Signed-off-by: Lauri Jakku --- drivers/usb/core/message.c | 55 ++++++++++++++++++++++++++++++++++---- 1 file changed, 50 insertions(+), 5 deletions(-) diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 5adf489428aa..2e0bfe70f7c5 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -20,6 +20,7 @@ #include /* for usbcore internals */ #include #include +#include #include "usb.h" @@ -137,7 +138,10 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u16 size, int timeout) { struct usb_ctrlrequest *dr; - int ret; + int ret = -ETIMEDOUT; + + /* retry_cnt * 20ms, max retry time set to 400ms */ + int retry_cnt = 20; dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO); if (!dr) @@ -149,11 +153,52 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, dr->wIndex = cpu_to_le16(index); dr->wLength = cpu_to_le16(size); - ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout); + do { + ret = usb_internal_control_msg(dev, + pipe, + dr, + data, + size, + timeout); + + /* + * Linger a bit, prior to the next control message + * or if return value is timeout, but do try few + * times (max 400ms) before quitting. Adapt timeout + * to be smaller when we have timeout'd first time. + */ + if (dev->quirks & USB_QUIRK_DELAY_CTRL_MSG) + msleep(200); + else if (ret == -ETIMEDOUT) { + static int timeout_happened = 0; + + if ( ! timeout_happened ) { + timeout_happened = 1; + + /* + * If timeout is given, divide it + * by 100, if not, put 10ms timeout. + * + * Then safeguard: if timeout is under + * 10ms, make timeout to be 10ms. + */ + + if (timeout > 0) + timeout /= 100; + else + timeout = 10; + + if (timeout < 10) + timeout = 10; + + } + + msleep(20); + } + + /* Loop while timeout, max loops: retry_cnt times. */ + } while ((retry_cnt-- > 0) && (ret == -ETIMEDOUT)); - /* Linger a bit, prior to the next control message. */ - if (dev->quirks & USB_QUIRK_DELAY_CTRL_MSG) - msleep(200); kfree(dr);