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=-8.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=ham 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 D0681C10F11 for ; Wed, 24 Apr 2019 16:21:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C268208E4 for ; Wed, 24 Apr 2019 16:21:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="eAwYSfz/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732181AbfDXQVY (ORCPT ); Wed, 24 Apr 2019 12:21:24 -0400 Received: from mail-pl1-f193.google.com ([209.85.214.193]:45494 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730600AbfDXQVY (ORCPT ); Wed, 24 Apr 2019 12:21:24 -0400 Received: by mail-pl1-f193.google.com with SMTP id o5so5205842pls.12; Wed, 24 Apr 2019 09:21:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=ggrZbKnvwmV8V20UN9/qhsb/WYrFJ6EC/6yM2DpPteE=; b=eAwYSfz/oIYdADq1IFJ72O3WMgqjBfgp2lII3Ubxhk+sRzLzWkCjA6EcC4q7hmt054 qs0NrRJ7gD7Ln3mXERYplORqE9DdXbXJoZTaoFYifExKCe9LDRgb4hmvbL25ZrXlxjq/ +ZDotzqhdVvG0ljJaQw5prOadVz8Nw7eyRYTo0W6di+hMO2K+KJXak8gaSYNP9hndfp8 EYqtI4cg0mlijVVZG80CC7RW37s7kVES2kiHAqCVvuDV33b9dTe5VfHAmjsNVePdSRPv BifIFIKxDHe89fFVY1vE3wqieLjPauk5pSM6G40pgSoJC4KfYnjkAhi0zMYo2a+G/skO klNg== 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:content-transfer-encoding :in-reply-to:user-agent; bh=ggrZbKnvwmV8V20UN9/qhsb/WYrFJ6EC/6yM2DpPteE=; b=g3N7siMp//npNecI4DhVf/sj4USUIEMPVZpbGzXuN/RyoQu+Obuk1WlcFycySB6ci5 htp7zqidcxZsZyr6PZ1xBkw0tvBFJrnqWEpb48lsQNVa4mnh7wZceeaezEChijKb7Q3H 1TWM9e9yQIbXyiTHbljniUBNgev4EnM2TMey9vNLSb5sQyxoUGTXBMVMncDyeTr6R54o XZFL7DonD+eGJoofvLT/jyVQR8brgnXVW3UuyBy670c4CoO7Juj+Pf9zlT/qbCuZR8aj 2VQXuirDL+klQ3PvqVkz+8XtX+jC68j/RQ7/zVowQJRRYsx7swApDxHK2y8mRCagDuE7 WFpw== X-Gm-Message-State: APjAAAVeCaafUGjmGvHAz3mE9QqACAu13UoFMmh+OFH67vuZV4emRbWH 7kDiOwlUmLpurTBG53IK17s= X-Google-Smtp-Source: APXvYqzZsuKtpk6gA/tzKydpAM9SKRvkgkFgywF+fhB9JxMXgVVr4z7XmWakdBJgldK4V1lAa03/nA== X-Received: by 2002:a17:902:b095:: with SMTP id p21mr1484406plr.40.1556122882959; Wed, 24 Apr 2019 09:21:22 -0700 (PDT) Received: from mail.google.com ([104.238.181.70]) by smtp.gmail.com with ESMTPSA id e6sm10852583pfe.158.2019.04.24.09.21.16 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 24 Apr 2019 09:21:22 -0700 (PDT) Date: Thu, 25 Apr 2019 00:21:12 +0800 From: Changbin Du To: Mauro Carvalho Chehab Cc: Changbin Du , Jonathan Corbet , Bjorn Helgaas , rjw@rjwysocki.net, linux-pci@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, fenghua.yu@intel.com, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-gpio@vger.kernel.org Subject: Re: [PATCH v4 08/63] Documentation: ACPI: move gpio-properties.txt to firmware-guide/acpi and convert to reST Message-ID: <20190424162111.i2ue6fyuxmsstdlk@mail.google.com> References: <20190423162932.21428-1-changbin.du@gmail.com> <20190423162932.21428-9-changbin.du@gmail.com> <20190423175515.58e78c0b@coco.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20190423175515.58e78c0b@coco.lan> User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 23, 2019 at 05:55:15PM -0300, Mauro Carvalho Chehab wrote: > Em Wed, 24 Apr 2019 00:28:37 +0800 > Changbin Du escreveu: > > > This converts the plain text documentation to reStructuredText format and > > add it to Sphinx TOC tree. No essential content change. > > > > Signed-off-by: Changbin Du > > --- > > .../acpi/gpio-properties.rst} | 78 +++++++++++-------- > > Documentation/firmware-guide/acpi/index.rst | 1 + > > MAINTAINERS | 2 +- > > 3 files changed, 46 insertions(+), 35 deletions(-) > > rename Documentation/{acpi/gpio-properties.txt => firmware-guide/acpi/gpio-properties.rst} (81%) > > > > diff --git a/Documentation/acpi/gpio-properties.txt b/Documentation/firmware-guide/acpi/gpio-properties.rst > > similarity index 81% > > rename from Documentation/acpi/gpio-properties.txt > > rename to Documentation/firmware-guide/acpi/gpio-properties.rst > > index 88c65cb5bf0a..89c636963544 100644 > > --- a/Documentation/acpi/gpio-properties.txt > > +++ b/Documentation/firmware-guide/acpi/gpio-properties.rst > > @@ -1,5 +1,8 @@ > > +.. SPDX-License-Identifier: GPL-2.0 > > + > > +====================================== > > _DSD Device Properties Related to GPIO > > --------------------------------------- > > +====================================== > > > > With the release of ACPI 5.1, the _DSD configuration object finally > > allows names to be given to GPIOs (and other things as well) returned > > @@ -8,7 +11,7 @@ the corresponding GPIO, which is pretty error prone (it depends on > > the _CRS output ordering, for example). > > > > With _DSD we can now query GPIOs using a name instead of an integer > > -index, like the ASL example below shows: > > +index, like the ASL example below shows:: > > > > // Bluetooth device with reset and shutdown GPIOs > > Device (BTH) > > @@ -34,15 +37,19 @@ index, like the ASL example below shows: > > }) > > } > > > > -The format of the supported GPIO property is: > > +The format of the supported GPIO property is:: > > > > Package () { "name", Package () { ref, index, pin, active_low }} > > > > - ref - The device that has _CRS containing GpioIo()/GpioInt() resources, > > - typically this is the device itself (BTH in our case). > > - index - Index of the GpioIo()/GpioInt() resource in _CRS starting from zero. > > - pin - Pin in the GpioIo()/GpioInt() resource. Typically this is zero. > > - active_low - If 1 the GPIO is marked as active_low. > > +ref > > + The device that has _CRS containing GpioIo()/GpioInt() resources, > > + typically this is the device itself (BTH in our case). > > +index > > + Index of the GpioIo()/GpioInt() resource in _CRS starting from zero. > > +pin > > + Pin in the GpioIo()/GpioInt() resource. Typically this is zero. > > +active_low > > + If 1 the GPIO is marked as active_low. > > > > Since ACPI GpioIo() resource does not have a field saying whether it is > > active low or high, the "active_low" argument can be used here. Setting > > @@ -55,7 +62,7 @@ It is possible to leave holes in the array of GPIOs. This is useful in > > cases like with SPI host controllers where some chip selects may be > > implemented as GPIOs and some as native signals. For example a SPI host > > controller can have chip selects 0 and 2 implemented as GPIOs and 1 as > > -native: > > +native:: > > > > Package () { > > "cs-gpios", > > @@ -67,7 +74,7 @@ native: > > } > > > > Other supported properties > > --------------------------- > > +========================== > > > > Following Device Tree compatible device properties are also supported by > > _DSD device properties for GPIO controllers: > > @@ -78,7 +85,7 @@ _DSD device properties for GPIO controllers: > > - input > > - line-name > > > > -Example: > > +Example:: > > > > Name (_DSD, Package () { > > // _DSD Hierarchical Properties Extension UUID > > @@ -100,7 +107,7 @@ Example: > > > > - gpio-line-names > > > > -Example: > > +Example:: > > > > Package () { > > "gpio-line-names", > > @@ -114,7 +121,7 @@ See Documentation/devicetree/bindings/gpio/gpio.txt for more information > > about these properties. > > > > ACPI GPIO Mappings Provided by Drivers > > --------------------------------------- > > +====================================== > > > > There are systems in which the ACPI tables do not contain _DSD but provide _CRS > > with GpioIo()/GpioInt() resources and device drivers still need to work with > > @@ -139,16 +146,16 @@ line in that resource starting from zero, and the active-low flag for that line, > > respectively, in analogy with the _DSD GPIO property format specified above. > > > > For the example Bluetooth device discussed previously the data structures in > > -question would look like this: > > +question would look like this:: > > > > -static const struct acpi_gpio_params reset_gpio = { 1, 1, false }; > > -static const struct acpi_gpio_params shutdown_gpio = { 0, 0, false }; > > + static const struct acpi_gpio_params reset_gpio = { 1, 1, false }; > > + static const struct acpi_gpio_params shutdown_gpio = { 0, 0, false }; > > > > -static const struct acpi_gpio_mapping bluetooth_acpi_gpios[] = { > > - { "reset-gpios", &reset_gpio, 1 }, > > - { "shutdown-gpios", &shutdown_gpio, 1 }, > > - { }, > > -}; > > + static const struct acpi_gpio_mapping bluetooth_acpi_gpios[] = { > > + { "reset-gpios", &reset_gpio, 1 }, > > + { "shutdown-gpios", &shutdown_gpio, 1 }, > > + { }, > > + }; > > > > Next, the mapping table needs to be passed as the second argument to > > acpi_dev_add_driver_gpios() that will register it with the ACPI device object > > @@ -158,12 +165,12 @@ calling acpi_dev_remove_driver_gpios() on the ACPI device object where that > > table was previously registered. > > > > Using the _CRS fallback > > ------------------------ > > +======================= > > > > If a device does not have _DSD or the driver does not create ACPI GPIO > > mapping, the Linux GPIO framework refuses to return any GPIOs. This is > > because the driver does not know what it actually gets. For example if we > > -have a device like below: > > +have a device like below:: > > > > Device (BTH) > > { > > @@ -177,7 +184,7 @@ have a device like below: > > }) > > } > > > > -The driver might expect to get the right GPIO when it does: > > +The driver might expect to get the right GPIO when it does:： > > Hmm... there is a small typo here: > > ": :" -> "::" > Good catch! Thanks. > For the conversion itself, after correcting the above typo: > > Reviewed-by: Mauro Carvalho Chehab > > > > > > > desc = gpiod_get(dev, "reset", GPIOD_OUT_LOW); > > > > @@ -193,22 +200,25 @@ the ACPI GPIO mapping tables are hardly linked to ACPI ID and certain > > objects, as listed in the above chapter, of the device in question. > > > > Getting GPIO descriptor > > ------------------------ > > +======================= > > + > > +There are two main approaches to get GPIO resource from ACPI:: > > > > -There are two main approaches to get GPIO resource from ACPI: > > - desc = gpiod_get(dev, connection_id, flags); > > - desc = gpiod_get_index(dev, connection_id, index, flags); > > + desc = gpiod_get(dev, connection_id, flags); > > + desc = gpiod_get_index(dev, connection_id, index, flags); > > > > We may consider two different cases here, i.e. when connection ID is > > provided and otherwise. > > > > -Case 1: > > - desc = gpiod_get(dev, "non-null-connection-id", flags); > > - desc = gpiod_get_index(dev, "non-null-connection-id", index, flags); > > +Case 1:: > > + > > + desc = gpiod_get(dev, "non-null-connection-id", flags); > > + desc = gpiod_get_index(dev, "non-null-connection-id", index, flags); > > + > > +Case 2:: > > > > -Case 2: > > - desc = gpiod_get(dev, NULL, flags); > > - desc = gpiod_get_index(dev, NULL, index, flags); > > + desc = gpiod_get(dev, NULL, flags); > > + desc = gpiod_get_index(dev, NULL, index, flags); > > > > Case 1 assumes that corresponding ACPI device description must have > > defined device properties and will prevent to getting any GPIO resources > > diff --git a/Documentation/firmware-guide/acpi/index.rst b/Documentation/firmware-guide/acpi/index.rst > > index 0e05b843521c..61d67763851b 100644 > > --- a/Documentation/firmware-guide/acpi/index.rst > > +++ b/Documentation/firmware-guide/acpi/index.rst > > @@ -11,3 +11,4 @@ ACPI Support > > enumeration > > osi > > DSD-properties-rules > > + gpio-properties > > diff --git a/MAINTAINERS b/MAINTAINERS > > index 09f43f1bdd15..87f930bf32ad 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -6593,7 +6593,7 @@ M: Andy Shevchenko > > L: linux-gpio@vger.kernel.org > > L: linux-acpi@vger.kernel.org > > S: Maintained > > -F: Documentation/acpi/gpio-properties.txt > > +F: Documentation/firmware-guide/acpi/gpio-properties.rst > > F: drivers/gpio/gpiolib-acpi.c > > > > GPIO IR Transmitter > > > > Thanks, > Mauro -- Cheers, Changbin Du