From patchwork Wed Jan 18 04:41:17 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Youn X-Patchwork-Id: 91728 Delivered-To: patch@linaro.org Received: by 10.140.20.99 with SMTP id 90csp843028qgi; Tue, 17 Jan 2017 20:49:51 -0800 (PST) X-Received: by 10.98.99.197 with SMTP id x188mr1509634pfb.179.1484714991360; Tue, 17 Jan 2017 20:49:51 -0800 (PST) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 33si20694807ple.107.2017.01.17.20.49.51; Tue, 17 Jan 2017 20:49:51 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-usb-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-usb-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-usb-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751342AbdAREtt (ORCPT + 4 others); Tue, 17 Jan 2017 23:49:49 -0500 Received: from us01smtprelay-2.synopsys.com ([198.182.60.111]:38394 "EHLO smtprelay.synopsys.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751157AbdAREtq (ORCPT ); Tue, 17 Jan 2017 23:49:46 -0500 Received: from mailhost.synopsys.com (mailhost3.synopsys.com [10.12.238.238]) by smtprelay.synopsys.com (Postfix) with ESMTP id 6162010C1663; Tue, 17 Jan 2017 20:41:23 -0800 (PST) Received: from mailhost.synopsys.com (localhost [127.0.0.1]) by mailhost.synopsys.com (Postfix) with ESMTP id 3B0EBABF; Tue, 17 Jan 2017 20:41:23 -0800 (PST) Received: from us01wehtc1.internal.synopsys.com (us01wehtc1-vip.internal.synopsys.com [10.12.239.236]) by mailhost.synopsys.com (Postfix) with ESMTP id 21BAFAB8; Tue, 17 Jan 2017 20:41:23 -0800 (PST) Received: from US01WEHTC3.internal.synopsys.com (10.15.84.232) by us01wehtc1.internal.synopsys.com (10.12.239.231) with Microsoft SMTP Server (TLS) id 14.3.266.1; Tue, 17 Jan 2017 20:41:19 -0800 Received: from starbug (10.13.184.20) by US01WEHTC3.internal.synopsys.com (10.15.84.231) with Microsoft SMTP Server (TLS) id 14.3.266.1; Tue, 17 Jan 2017 20:41:17 -0800 Received: by starbug (sSMTP sendmail emulation); Tue, 17 Jan 2017 20:41:17 -0800 Date: Tue, 17 Jan 2017 20:41:17 -0800 Message-ID: <75a5d7c16d56118a6794cb9ed0da93db21b99810.1484704738.git.johnyoun@synopsys.com> In-Reply-To: References: From: John Youn Subject: [PATCH v2 23/28] usb: dwc2: Workaround case where GOTGCTL state is wrong To: John Youn , Felipe Balbi , CC: Vardan Mikayelyan , Rob Herring , Kishon Vijay Abraham I , Amit Pundir , John Stultz , Wei Xu , Guodong Xu , Chen Yu , Stefan Wahren , "Douglas Anderson" MIME-Version: 1.0 X-Originating-IP: [10.13.184.20] Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: John Stultz When removing a USB-A to USB-otg adapter cable, we get a change status irq, and then in dwc2_conn_id_status_change, we erroniously see the GOTGCTL_CONID_B flag set. This causes us to get stuck in the "while (!dwc2_is_device_mode(hsotg))" loop, spitting out "Waiting for Peripheral Mode, Mode=Host" warnings until it fails out many seconds later. This patch works around the issue by re-reading the GOTGCTL state to check if the GOTGCTL_CONID_B is still set and if not restarting the change status logic. I suspect this isn't the best solution, but it seems to work well for me. Feedback would be greatly appreciated! Cc: Wei Xu Cc: Guodong Xu Cc: Amit Pundir Cc: Rob Herring Cc: John Youn Cc: Douglas Anderson Cc: Chen Yu Cc: Vardan Mikayelyan Cc: Kishon Vijay Abraham I Cc: Felipe Balbi Cc: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org Reviewed-by: Vardan Mikayelyan Signed-off-by: John Stultz Signed-off-by: John Youn --- drivers/usb/dwc2/hcd.c | 9 +++++++++ 1 file changed, 9 insertions(+) -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 2c13a35922e1..274d64b5355c 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -3237,6 +3237,14 @@ static void dwc2_conn_id_status_change(struct work_struct *work) dwc2_is_host_mode(hsotg) ? "Host" : "Peripheral"); usleep_range(20000, 40000); + /* + * Sometimes the initial GOTGCTRL read is wrong, so + * check it again and jump to host mode if that was + * the case. + */ + gotgctl = dwc2_readl(hsotg->regs + GOTGCTL); + if (!(gotgctl & GOTGCTL_CONID_B)) + goto host; if (++count > 250) break; } @@ -3251,6 +3259,7 @@ static void dwc2_conn_id_status_change(struct work_struct *work) spin_unlock_irqrestore(&hsotg->lock, flags); dwc2_hsotg_core_connect(hsotg); } else { +host: /* A-Device connector (Host Mode) */ dev_dbg(hsotg->dev, "connId A\n"); while (!dwc2_is_host_mode(hsotg)) {