From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 39985C04AAF for ; Thu, 16 May 2019 23:00:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0A1BE20862 for ; Thu, 16 May 2019 23:00:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="nSXc80/C" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727122AbfEPXAG (ORCPT ); Thu, 16 May 2019 19:00:06 -0400 Received: from mail-pg1-f193.google.com ([209.85.215.193]:37156 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726950AbfEPXAD (ORCPT ); Thu, 16 May 2019 19:00:03 -0400 Received: by mail-pg1-f193.google.com with SMTP id e6so2279191pgc.4 for ; Thu, 16 May 2019 16:00:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=3AN0TJJxN8MtDzX5Iph5PzGAe+8Uoxx6FUdLGJx7ICE=; b=nSXc80/CuM7wCAu9eEfz822i+s8PDxGqnuq6ulYoRqo35+23kjL0xS8NheIX44Zraw rHeSNCKU0+k3HLIVvspnPamHZXfPlhP82YCNxizzRQz7yxOpi1XwunB/0QNgM7KA2Ksa aJRD7udcbWEk0s+aQzZft/R2d52644y+TzVDQ= 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:mime-version:content-transfer-encoding; bh=3AN0TJJxN8MtDzX5Iph5PzGAe+8Uoxx6FUdLGJx7ICE=; b=ZGvT+3J2MYVFnWMK9xq6+vZoemfl+g11nt4j874YshqZESaeEwQplcWXETIZrRYC73 TLbvBfPs4rOiK3RD6wahblBvaUCsBS0dh0e3YVXAghD2w1xpM6b1VwihFVND19q8SGjC i0jPKhaNY4jT+WgIqhyTD+xQBW9DhA43PCTPFGnbbt4NVXTCUVicalhRWGOmNQ7M8jPY icVn7e0FiENeR7wDYbohs3XEGeZlGtZVRVE4sRyWEdtsOxzDLtu6NRRhgyfQyn6qKlxc g7VBYZVMmYDVLbK/NXmr6CafUKZI28eZWVeaCBMGbFeh+Qz2aXP9gxb8W6RgSD6hOnLe Id4Q== X-Gm-Message-State: APjAAAWqPe11uF6qff8w/FFf1QtcTyLDUIF5FdUMlwC0k8IXpYIYwXBO tzVFplE8ex8aqgW1LFRQAwvaqA== X-Google-Smtp-Source: APXvYqylgevqrKIDD/mmUDsN1EbCBsMcMGLJn9tGRUV9ROjY5j75gDluyLf/UhG80yxA5Tcwvvm4cQ== X-Received: by 2002:a62:4d03:: with SMTP id a3mr58452313pfb.2.1558047600933; Thu, 16 May 2019 16:00:00 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id j64sm1769506pfb.126.2019.05.16.15.59.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 16 May 2019 16:00:00 -0700 (PDT) From: Douglas Anderson To: Minas Harutyunyan , Felipe Balbi , heiko@sntech.de Cc: Alan Stern , Artur Petrosyan , amstan@chromium.org, linux-rockchip@lists.infradead.org, William Wu , linux-usb@vger.kernel.org, Stefan Wahren , Randy Li , zyw@rock-chips.com, mka@chromium.org, ryandcase@chromium.org, Amelie Delaunay , jwerner@chromium.org, dinguyen@opensource.altera.com, Elaine Zhang , Douglas Anderson , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Rob Herring , Greg Kroah-Hartman , Mark Rutland Subject: [REPOST PATCH v2 1/3] Documentation: dt-bindings: Add snps,need-phy-for-wake for dwc2 USB Date: Thu, 16 May 2019 15:59:39 -0700 Message-Id: <20190516225941.170355-2-dianders@chromium.org> X-Mailer: git-send-email 2.21.0.1020.gf2820cf01a-goog In-Reply-To: <20190516225941.170355-1-dianders@chromium.org> References: <20190516225941.170355-1-dianders@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some SoCs with a dwc2 USB controller may need to keep the PHY on to support remote wakeup. Allow specifying this as a device tree property. Signed-off-by: Douglas Anderson --- For relevant prior discussion on this patch, see: https://lkml.kernel.org/r/1435017144-2971-3-git-send-email-dianders@chromium.org I didn't make any changes from the prior version since I never found out what Rob thought of my previous arguments. If folks want a change, perhaps they could choose from these options: 1. Assume that all dwc2 hosts would like to keep their PHY on for suspend if there's a USB wakeup enabled, thus we totally drop this binding. This doesn't seem super great to me since I'd bet that many devices that use dwc2 weren't designed for USB wakeup (they may not keep enough clocks or rails on) so we might be wasting power for nothing. 2. Rename this property to "snps,wakeup-from-suspend-with-phy" to make it more obvious that this property is intended both to document that wakeup from suspend is possible and that we need the PHY for said wakeup. 3. Rename this property to "snps,can-wakeup-from-suspend" and assume it's implicit that if we can wakeup from suspend that we need to keep the PHY on. If/when someone shows that a device exists using dwc2 where we can wakeup from suspend without the PHY they can add a new property. NOTE FOR REPOST: - In v2 Rob said [1] he'd prefer something based on the SoC compatibility string, but that doesn't work because not all boards will have the regulator setup / board design / suspend logic necessary to make this work. [1] https://lkml.kernel.org/r/20190430012328.GA25660@bogus Changes in v2: None Documentation/devicetree/bindings/usb/dwc2.txt | 3 +++ 1 file changed, 3 insertions(+) diff --git a/Documentation/devicetree/bindings/usb/dwc2.txt b/Documentation/devicetree/bindings/usb/dwc2.txt index 49eac0dc86b0..aafff3a6904d 100644 --- a/Documentation/devicetree/bindings/usb/dwc2.txt +++ b/Documentation/devicetree/bindings/usb/dwc2.txt @@ -42,6 +42,8 @@ Refer to phy/phy-bindings.txt for generic phy consumer properties - g-rx-fifo-size: size of rx fifo size in gadget mode. - g-np-tx-fifo-size: size of non-periodic tx fifo size in gadget mode. - g-tx-fifo-size: size of periodic tx fifo per endpoint (except ep0) in gadget mode. +- snps,need-phy-for-wake: If present indicates that the phy needs to be left + on for remote wakeup during suspend. - snps,reset-phy-on-wake: If present indicates that we need to reset the PHY when we detect a wakeup. This is due to a hardware errata. @@ -58,4 +60,5 @@ Example: clock-names = "otg"; phys = <&usbphy>; phy-names = "usb2-phy"; + snps,need-phy-for-wake; }; -- 2.21.0.1020.gf2820cf01a-goog