From patchwork Thu Apr 18 00:13:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 10906407 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 15D9814DB for ; Thu, 18 Apr 2019 00:15:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EFFF928BD4 for ; Thu, 18 Apr 2019 00:15:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E428A28BD7; Thu, 18 Apr 2019 00:15:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7EE6428BD4 for ; Thu, 18 Apr 2019 00:15:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387791AbfDRAPB (ORCPT ); Wed, 17 Apr 2019 20:15:01 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:46161 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387782AbfDRAPB (ORCPT ); Wed, 17 Apr 2019 20:15:01 -0400 Received: by mail-pg1-f195.google.com with SMTP id q1so284834pgv.13 for ; Wed, 17 Apr 2019 17:15:00 -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=8a+BZEe7v/lxE++Jk26DJvDIeRtcgS+edmxjVgSar6E=; b=IVSeUaSONgbK9dI1ta/UwuOc1HRfMQvPSCtcNOmVBdiHzUEh6REoeZBCONmL+PZwSV gdii0s7Vx/s52jH8A1PQYwkkHw9YqXyjHxrrr/jGLWyyR7H1KXSZpkgeusUpVeqsGy6D hURXqfMjL0W5jtLLmOK6G1hVPp3iOLlOrIF3A= 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=8a+BZEe7v/lxE++Jk26DJvDIeRtcgS+edmxjVgSar6E=; b=BmCSoLXeZzvZgfjcHbivHOSqGqYNapG6CyWM6AYhHolZi/K5hUMGyAx2JwnEEhbi3t /ThZ4ZupItdmMbqMHg5guLdm5emqIocSO9eZtXuLEXexRYbXj7Efcg1sf/btek0Vu77M pHe/18u7xooD6odPDmzxFKkMDQuZIOdrLUirQAIoPFD19fu81Tjt79lfUzhX7WZAqjc0 qT4VFlegtlpJ6DSwNLPnZOwvVi6Sws6HOC7+dLvkncy+h9/yHLycTcKdKQjggylkGEVU WuKD93dssy9eWfP18+BYVhOXy+54KGJ5Ho12rlBtxoIF2iS22e9gap1MNqKYyXq8F3KE CH1w== X-Gm-Message-State: APjAAAVwnpyAVgs2jX3HjNdV2hmtyG7O4FQOKASOuPIBGWAqcnqARRM+ KLBmBwA20Ldc5HbttCDVXmgzGg== X-Google-Smtp-Source: APXvYqxYqSg78iVNlYmCW86sspNg6ANcr7iduniZLCDqL6dcz9Jy0fjB/9qbeZkfU6namPKEZg5IPQ== X-Received: by 2002:a62:6fc6:: with SMTP id k189mr74302179pfc.154.1555546500578; Wed, 17 Apr 2019 17:15:00 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id q5sm447668pff.97.2019.04.17.17.14.59 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 17 Apr 2019 17:15:00 -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: [PATCH v2 3/5] Documentation: dt-bindings: Add snps,need-phy-for-wake for dwc2 USB Date: Wed, 17 Apr 2019 17:13:54 -0700 Message-Id: <20190418001356.124334-4-dianders@chromium.org> X-Mailer: git-send-email 2.21.0.593.g511ec345e18-goog In-Reply-To: <20190418001356.124334-1-dianders@chromium.org> References: <20190418001356.124334-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP 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. 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 f70f3aee4bfc..1c5e29d23c51 100644 --- a/Documentation/devicetree/bindings/usb/dwc2.txt +++ b/Documentation/devicetree/bindings/usb/dwc2.txt @@ -37,6 +37,8 @@ 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. @@ -53,4 +55,5 @@ Example: clock-names = "otg"; phys = <&usbphy>; phy-names = "usb2-phy"; + snps,need-phy-for-wake; };