From patchwork Thu Feb 3 08:00:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 540035 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63228C433EF for ; Thu, 3 Feb 2022 08:00:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242583AbiBCIAi (ORCPT ); Thu, 3 Feb 2022 03:00:38 -0500 Received: from alexa-out-sd-02.qualcomm.com ([199.106.114.39]:59011 "EHLO alexa-out-sd-02.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243764AbiBCIAf (ORCPT ); Thu, 3 Feb 2022 03:00:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1643875235; x=1675411235; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=qxnGpZbD0kpPes3OMo1bth+EcSxHpnt3Lvs3J3lXJps=; b=ob61RYbJgaT5CGpfWLTIVHD4IYyUlg0GfTryeCeYLJErQhjGrqdg9LZS FAlih3FT1B+BS9OdTw0MbCQ8M1LD+FcYrnK2QCUFVaKbW4Yzo7yvHsoIX C9l+oS8wePDluAKkWL5IoWCbr5uXVnEV/DNxs+rZO62HgZiMoLCvuD2YQ Q=; Received: from unknown (HELO ironmsg03-sd.qualcomm.com) ([10.53.140.143]) by alexa-out-sd-02.qualcomm.com with ESMTP; 03 Feb 2022 00:00:34 -0800 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg03-sd.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Feb 2022 00:00:34 -0800 Received: from nalasex01b.na.qualcomm.com (10.47.209.197) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.19; Thu, 3 Feb 2022 00:00:34 -0800 Received: from wcheng-linux.qualcomm.com (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.19; Thu, 3 Feb 2022 00:00:33 -0800 From: Wesley Cheng To: , CC: , , , , Wesley Cheng Subject: [RFC PATCH 3/3] usb: dwc3: Issue core soft reset before enabling run/stop Date: Thu, 3 Feb 2022 00:00:17 -0800 Message-ID: <20220203080017.27339-4-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20220203080017.27339-1-quic_wcheng@quicinc.com> References: <20220203080017.27339-1-quic_wcheng@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01b.na.qualcomm.com (10.47.209.197) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org It is recommended by the Synopsis databook to issue a DCTL.CSftReset when reconnecting from a device-initiated disconnect routine. This resolves issues with enumeration during fast composition switching cases, which result in an unknown device on the host. Signed-off-by: Wesley Cheng --- drivers/usb/dwc3/core.c | 4 +--- drivers/usb/dwc3/core.h | 2 ++ drivers/usb/dwc3/gadget.c | 11 +++++++++++ 3 files changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index f4c09951b517..d128c7f22b01 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -115,8 +115,6 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode) dwc->current_dr_role = mode; } -static int dwc3_core_soft_reset(struct dwc3 *dwc); - static void __dwc3_set_mode(struct work_struct *work) { struct dwc3 *dwc = work_to_dwc(work); @@ -261,7 +259,7 @@ u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type) * dwc3_core_soft_reset - Issues core soft reset and PHY reset * @dwc: pointer to our context structure */ -static int dwc3_core_soft_reset(struct dwc3 *dwc) +int dwc3_core_soft_reset(struct dwc3 *dwc) { u32 reg; int retries = 1000; diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index d418ed55a566..e15b83a6f094 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1527,6 +1527,8 @@ bool dwc3_has_imod(struct dwc3 *dwc); int dwc3_event_buffers_setup(struct dwc3 *dwc); void dwc3_event_buffers_cleanup(struct dwc3 *dwc); +int dwc3_core_soft_reset(struct dwc3 *dwc); + #if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE) int dwc3_host_init(struct dwc3 *dwc); void dwc3_host_exit(struct dwc3 *dwc); diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 1efa30907d42..94cfbe32da8d 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2572,6 +2572,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) dwc->ev_buf->length; } } else { + /* + * In the Synopsis DesignWare Cores USB3 Databook Rev. 1.90a + * Section 4.1.9, it specifies that for a reconnect after a + * device-initiated disconnect requires a core soft reset + * (DCTL.CSftRst) before enabling the run/stop bit. + */ + spin_unlock_irqrestore(&dwc->lock, flags); + dwc3_core_soft_reset(dwc); + spin_lock_irqsave(&dwc->lock, flags); + + dwc3_event_buffers_setup(dwc); __dwc3_gadget_start(dwc); }