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=-12.8 required=3.0 tests=BAYES_00,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, URIBL_BLOCKED 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 E9C23C43461 for ; Wed, 16 Sep 2020 00:01:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A9C8120756 for ; Wed, 16 Sep 2020 00:01:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="I182+EMg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727111AbgIPABp (ORCPT ); Tue, 15 Sep 2020 20:01:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38824 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727198AbgIPAAK (ORCPT ); Tue, 15 Sep 2020 20:00:10 -0400 Received: from mail-pl1-x642.google.com (mail-pl1-x642.google.com [IPv6:2607:f8b0:4864:20::642]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F3570C06174A for ; Tue, 15 Sep 2020 17:00:09 -0700 (PDT) Received: by mail-pl1-x642.google.com with SMTP id k13so2189274plk.3 for ; Tue, 15 Sep 2020 17:00:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=RX3pgRSaqwuA91vHSgRiOLr6fZp+r278bl7l934MXzo=; b=I182+EMgnVlXeJ47Jpn+7tZxBNwd0Q4oeX34HqBM9qVe+Kc3Ch8LGnghFtFaFDoiI+ HGm8fXrJUu2L+YhOwQAi8t6WDe4uJ4ADZRBofop4MrMgBTQdJC1IICusIXpVTxM24MYu CHV5T8SHE9ZaD5FzAtY921nrac1crYXcu8ErQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=RX3pgRSaqwuA91vHSgRiOLr6fZp+r278bl7l934MXzo=; b=EPNqAyQJZckibBSlALWpro2wybbVARgkTWyQDhRRF8LAlq8wafw3hViziYY/vO3bOc ZVWxaxiypEqu46ZPqaQz/+FyfeSMQ2YXPwVgnYxgw6g80Jizv+z5zO3usaHLG5YfxF8e UlmIofOVx4nKk7lDYJImeD4blQWzjjVtHh+7khKWs7Ius69FoWxiMILr9t3cljPfOMGd g80LutC8yGiDvYnHGD89IdNYpf9zLgQuLqMCqWoF60HzkYYKUo7WKPOqBtDhbByAJ8/S cOi1kOZ/wutaNtMyGWhWusxrQjBpbvGM0AmFzlOeM/R6j4Ah3erblQISdP4NFzgbrvrk FIRw== X-Gm-Message-State: AOAM53021uT/xjIz0Fw6yoclXEHIleoaa0YQEsyDohffb4yzD2sd4Mmt I80DnAEM7rQ/LYB2ylubh6hi0w== X-Google-Smtp-Source: ABdhPJx2q0kjfen9gHcVuYxqbdmmHRWRJidwPFOESeIQIJnD+CHVVXk6+U17mQhEWN8yg8Sb2ToONw== X-Received: by 2002:a17:90a:8981:: with SMTP id v1mr1640899pjn.54.1600214409487; Tue, 15 Sep 2020 17:00:09 -0700 (PDT) Received: from localhost ([2620:15c:202:1:f693:9fff:fef4:e70a]) by smtp.gmail.com with ESMTPSA id e10sm542754pjj.32.2020.09.15.17.00.08 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 15 Sep 2020 17:00:09 -0700 (PDT) Date: Tue, 15 Sep 2020 17:00:08 -0700 From: Matthias Kaehlcke To: Rob Herring Cc: Greg Kroah-Hartman , Frank Rowand , Alan Stern , Krzysztof Kozlowski , Bastien Nocera , Ravi Chandra Sadineni , linux-usb@vger.kernel.org, Stephen Boyd , devicetree@vger.kernel.org, Douglas Anderson , Peter Chen , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] dt-bindings: usb: Add binding for onboard USB hubs Message-ID: <20200916000008.GG2771744@google.com> References: <20200914112716.1.I248292623d3d0f6a4f0c5bc58478ca3c0062b49a@changeid> <20200915142145.GA1861636@bogus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200915142145.GA1861636@bogus> Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi Rob, On Tue, Sep 15, 2020 at 08:21:45AM -0600, Rob Herring wrote: > On Mon, Sep 14, 2020 at 11:27:48AM -0700, Matthias Kaehlcke wrote: > > Onboard USB hubs need to be powered and may require initiaization of > > other resources (like GPIOs or clocks) to work properly. This adds > > a device tree binding for these hubs. > > We already have bindings for these. 2 in fact as I2C controlled hubs are > often described under the I2C bus. Yes, these are I2C controlled hubs, which need hub specific drivers. This driver is for hubs without an additional bus that share similar initialization requirements and can benefit from common functionality. > > Signed-off-by: Matthias Kaehlcke > > --- > > > > .../bindings/usb/onboard_usb_hub.yaml | 70 +++++++++++++++++++ > > 1 file changed, 70 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/usb/onboard_usb_hub.yaml > > > > diff --git a/Documentation/devicetree/bindings/usb/onboard_usb_hub.yaml b/Documentation/devicetree/bindings/usb/onboard_usb_hub.yaml > > new file mode 100644 > > index 000000000000..f82d8f459eed > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/usb/onboard_usb_hub.yaml > > @@ -0,0 +1,70 @@ > > +# SPDX-License-Identifier: GPL-2.0-only or BSD-2-Clause > > +%YAML 1.2 > > +--- > > +$id: http://devicetree.org/schemas/usb/onboard_usb_hub.yaml# > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > + > > +title: Binding for onboard USB hubs > > + > > +maintainers: > > + - Matthias Kaehlcke > > + > > +allOf: > > + - $ref: /schemas/usb/onboard_usb_hub.yaml# > > + > > +properties: > > + compatible: > > + enum: > > + - onboard-usb-hub > > + - realtek,rts5411 > > + > > + power-off-in-suspend: > > + description: > > + The hub should be powered off during system suspend. When the > > + "wakeup-source" property is also provided the hub is only powered > > + off during suspend when no wakeup capable descendants are connected. > > + type: boolean > > + > > + vdd-supply: > > + description: > > + phandle to the regulator that provides power to the hub. > > + > > + wakeup-source: > > + description: > > + Wakeup capable USB devices connected to this hub can be used as > > + wakeup source. > > + type: boolean > > + > > +required: > > + - compatible > > + - vdd-supply > > + > > +examples: > > + - | > > + usb_hub: usb-hub { > > + compatible = "realtek,rts5411", "onboard-usb-hub"; > > + vdd-supply = <&pp3300_hub>; > > + power-off-in-suspend; > > + wakeup-source; > > This is the hub device? This is the physical hub device on the platform bus, which is the equivalent to this entry for a usb2512b hub on an I2C bus: usb2512b@2c { compatible = "microchip,usb2512b"; reg = <0x2c>; reset-gpios = <&gpio1 4 GPIO_ACTIVE_LOW>; }; (source: Documentation/devicetree/bindings/usb/usb251xb.txt) It doesn't have an I2C, SPI or other bus, hence the platform bus is used. > > + }; > > + > > + &usb_1_dwc3 { > > + dr_mode = "host"; > > + #address-cells = <1>; > > + #size-cells = <0>; > > + > > + /* 2.0 hub on port 1 */ > > + hub@1 { > > + compatible = "usbbda,5411"; > > + reg = <1>; > > + hub = <&usb_hub>; > > Or this node is? It is the USB 2.0 part of the hub. The device is instantiated by Linux even without this node, but the system associates the node with the device, which suggests it 'exists'. The usb2512b mentioned above implicitly also has a node here, it just isn't specified since the USB controller autodetects it. > > + }; > > + > > + /* 3.0 hub on port 2 */ > > + hub@2 { > > + compatible = "usbbda,411"; > > + reg = <2>; > > + hub = <&usb_hub>; > > Or this node is? It is the USB 3.0 part of the hub. > The hub node belongs here. The platform device isn't probed when the node is inside the USB controller node. I haven't investigated why that's the case. > If you really have it connected to 2 upstream ports, then just do > one node with 'reg = <1 2>;'. Yes, it is connected to two upstream ports. The platform driver needs a reference to both/all hubs, to be able to determine whether to keep the hub powered during system suspend or not. Technically the hub with product id 0x5411 is connected to port 1 and the one with product id 0x411 to port 2, so I would say the above is more accurate than pretending one of the hubs is connected to both ports. I would argue that the two hub nodes are similar to a SDIO BT/WiFi combo, where you have one chip/module with multiple functions. The DT has entries for both functions, even though they reside in the same chip and share the same bus.