From patchwork Fri Jan 8 01:51:15 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Stultz X-Patchwork-Id: 12005559 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6C042C433E6 for ; Fri, 8 Jan 2021 01:52:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2DBD923601 for ; Fri, 8 Jan 2021 01:52:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729872AbhAHBwE (ORCPT ); Thu, 7 Jan 2021 20:52:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729778AbhAHBwE (ORCPT ); Thu, 7 Jan 2021 20:52:04 -0500 Received: from mail-pg1-x532.google.com (mail-pg1-x532.google.com [IPv6:2607:f8b0:4864:20::532]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2EA56C0612F6 for ; Thu, 7 Jan 2021 17:51:24 -0800 (PST) Received: by mail-pg1-x532.google.com with SMTP id n7so6640242pgg.2 for ; Thu, 07 Jan 2021 17:51:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=eaHrQpKpeurHZv+OYTMBBGGPpB4FZE1mWJW48Z/oiNs=; b=AP8eKNDXK+f3yABttnermAH/48jx7jQD5O+GUTNSbdHW4WUqvESmttKvccFPZgp9Sz A/YcciJTOSsQ6+nNIXjhfmrvn0z5OHXeNczZZtuJ9rOh7lSh2pqKfx1H2QasQsPXu2uW b1XW6ubHyF2oGGSxPTrqhF2hOxNrVgHdoUz0tmPRsD9X+RpmSPMkEOi+kpNicXxGr+Uh dly3HIYPB8GjbhlHvWkUJleD9z8FLiohhDzF1EsJjM3RLPjrtmilqEhb2JCvPpLx5+jP zvTUmqdeh6WWeEkQNyu6ssL4OkK/K2O/JsOZIJZzTcpa872nVlRHmbZtZOl5GIBDIbrq 36WA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=eaHrQpKpeurHZv+OYTMBBGGPpB4FZE1mWJW48Z/oiNs=; b=T2bXjj7NuS4nx8tIuq40sprrkZHZOPPPdsLUJGSXP+twWkJwuymWAyQr3wie6Rf/PH 7Y6OkQn1lgCLXJKMzMwXXG47OW1imFGSYuavHT0pk2ECyrbH+V+UNPIyy1tTx2RK2SYV dzaHc9lIsQ1rYgknx5i+C+1Ljz2Wry9hagi9IccGYEQBvY5THOSrpSzM+bsXtla0k5OE 7MdJF3rNxRtOsu7MY6TbMJ6dfUfFijKe1MqhjarlmwRNFoHjCAQswRIp7ghLBEOFPOKG fdo1FQ42yWTlS2CQtTj4zj2jVrAe0wO27MkwZr6XEjVEPuOYEabUfKUeMB6VlGuSpXaV SybQ== X-Gm-Message-State: AOAM532s9Htu7ebR2ClvU3QExnZS8JjrZgRrA01BYSualrqKTbrpnR9I o4q/CG+//SjAx3LjDQewE0Ruxg== X-Google-Smtp-Source: ABdhPJxSbJhBpM2A0dR5cqQKxAWgztVnTaKnRROtWkb337/i7shPcaEJlVeBtCPmt827WMdg7g/VlA== X-Received: by 2002:a63:1261:: with SMTP id 33mr4538228pgs.213.1610070683769; Thu, 07 Jan 2021 17:51:23 -0800 (PST) Received: from localhost.localdomain ([2601:1c2:680:1319:692:26ff:feda:3a81]) by smtp.gmail.com with ESMTPSA id fw12sm6142756pjb.43.2021.01.07.17.51.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Jan 2021 17:51:22 -0800 (PST) From: John Stultz To: lkml Cc: John Stultz , Felipe Balbi , Tejas Joglekar , Yang Fei , YongQin Liu , Andrzej Pietrasiewicz , Thinh Nguyen , Jun Li , Mauro Carvalho Chehab , Greg Kroah-Hartman , linux-usb@vger.kernel.org Subject: [PATCH v3 2/2] usb: dwc3: Fix DRD mode change sequence following programming guide Date: Fri, 8 Jan 2021 01:51:15 +0000 Message-Id: <20210108015115.27920-2-john.stultz@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210108015115.27920-1-john.stultz@linaro.org> References: <20210108015115.27920-1-john.stultz@linaro.org> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In reviewing the previous patch, Thinh Nguyen pointed out that the DRD mode change sequence should be like the following when switching from host -> device according to the programming guide (for all DRD IPs): 1. Reset controller with GCTL.CoreSoftReset 2. Set GCTL.PrtCapDir(device) 3. Soft reset with DCTL.CSftRst 4. Then follow up with the initializing registers sequence The current code does: a. Soft reset with DCTL.CSftRst on driver probe b. Reset controller with GCTL.CoreSoftReset (added in previous patch) c. Set GCTL.PrtCapDir(device) d. < missing DCTL.CSftRst > e. Then follow up with initializing registers sequence So this patch adds the DCTL.CSftRst soft reset that was currently missing from the dwc3 mode switching. Cc: Felipe Balbi Cc: Tejas Joglekar Cc: Yang Fei Cc: YongQin Liu Cc: Andrzej Pietrasiewicz Cc: Thinh Nguyen Cc: Jun Li Cc: Mauro Carvalho Chehab Cc: Greg Kroah-Hartman Cc: linux-usb@vger.kernel.org Signed-off-by: John Stultz --- Feedback would be appreciated. I'm a little worried I should be conditionalizing the DCTL.CSftRst on DRD mode controllers, but I'm really not sure what the right thing to do is for non-DRD mode controllers. --- drivers/usb/dwc3/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index b6a6b90eb2d5..71f8b07ecb99 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -40,6 +40,8 @@ #define DWC3_DEFAULT_AUTOSUSPEND_DELAY 5000 /* ms */ +static int dwc3_core_soft_reset(struct dwc3 *dwc); + /** * dwc3_get_dr_mode - Validates and sets dr_mode * @dwc: pointer to our context structure @@ -177,6 +179,7 @@ static void __dwc3_set_mode(struct work_struct *work) dwc3_set_prtcap(dwc, dwc->desired_dr_role); + dwc3_core_soft_reset(dwc); spin_unlock_irqrestore(&dwc->lock, flags); switch (dwc->desired_dr_role) {