From patchwork Wed Sep 2 18:07:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dirk Behme X-Patchwork-Id: 513606 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 80C1F140273 for ; Thu, 3 Sep 2015 04:07:18 +1000 (AEST) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b=K9pB4Ro+; dkim-atps=neutral Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755774AbbIBSHR (ORCPT ); Wed, 2 Sep 2015 14:07:17 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:36497 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755406AbbIBSHQ (ORCPT ); Wed, 2 Sep 2015 14:07:16 -0400 Received: by wibz8 with SMTP id z8so74563351wib.1 for ; Wed, 02 Sep 2015 11:07:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=gHgwxf71VGG5ACoDBDLdn4hf67laH76x2QhzOImly9E=; b=K9pB4Ro++oXBWRxP7jDkgbxGPrc5jOeCrv2ldHUL2Ie0YjSgJubPh0fVk5GdamJ1jJ db75lGL/xqOmPhiEwqOod7rwxohlPE4GFxyvb7Fts9ouIsBfO352ougOc9x31BKytcOb ribg7fkCIx7IjdjMmQTi3H67b0B4Uq3MbefoIyRBl/1//ON2EK4DYhlMa1XSYa8OSgLL 9pG43yu+FHwdzYOTnmpRlMCmCbyWJ0PMCFbyG8FZ35AZUaeu7M+nPoOMgATH2fs+g6Iy U2HOtuYgSltrXytAsrDI3dnafs+um8UtKdnCEWU1wDMN9Kf7owfD9oX220zU/jezvd/X Cv0g== X-Received: by 10.194.171.129 with SMTP id au1mr44851365wjc.115.1441217235592; Wed, 02 Sep 2015 11:07:15 -0700 (PDT) Received: from localhost.localdomain (p4FEE232A.dip0.t-ipconnect.de. [79.238.35.42]) by smtp.gmail.com with ESMTPSA id c10sm4808232wiy.1.2015.09.02.11.07.14 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 02 Sep 2015 11:07:15 -0700 (PDT) From: Dirk Behme To: Alexandre Courbot , Linus Walleij Cc: linux-gpio@vger.kernel.org, Dirk Behme Subject: [PATCH 2/2 v3] Documentation: gpio: board: describe the con_id parameter Date: Wed, 2 Sep 2015 20:07:10 +0200 Message-Id: <1441217230-4530-2-git-send-email-dirk.behme@gmail.com> X-Mailer: git-send-email 2.5.1 In-Reply-To: <1441217230-4530-1-git-send-email-dirk.behme@gmail.com> References: <1441217230-4530-1-git-send-email-dirk.behme@gmail.com> Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org The con_id parameter has to match the GPIO description and is automatically extended by the GPIO suffix if not NULL. I had to look into the code to understand this and properly find the GPIO I've been looking for, so document this. Signed-off-by: Dirk Behme Acked-by: Alexandre Courbot --- Documentation/gpio/board.txt | 9 +++++++++ Documentation/gpio/consumer.txt | 3 +++ 2 files changed, 12 insertions(+) diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt index 9edd5af..5fa069a 100644 --- a/Documentation/gpio/board.txt +++ b/Documentation/gpio/board.txt @@ -48,6 +48,15 @@ This property will make GPIOs 15, 16 and 17 available to the driver under the The led GPIOs will be active-high, while the power GPIO will be active-low (i.e. gpiod_is_active_low(power) will be true). +The second parameter of the gpiod_get() functions, the con_id string, has to be +the -prefix of the GPIO suffixes ("gpios" or "gpio", automatically +looked up by the gpiod functions internally) used in the device tree. With above +"led-gpios" example, use the prefix without the "-" as con_id parameter: "led". + +Internally, the GPIO subsystem prefixes the GPIO suffix ("gpios" or "gpio") +with the string passed in con_id to get the resulting string +(snprintf(... "%s-%s", con_id, gpio_suffixes[]). + ACPI ---- ACPI also supports function names for GPIOs in a similar fashion to DT. diff --git a/Documentation/gpio/consumer.txt b/Documentation/gpio/consumer.txt index 75542b9..47ce4fd 100644 --- a/Documentation/gpio/consumer.txt +++ b/Documentation/gpio/consumer.txt @@ -39,6 +39,9 @@ device that displays digits), an additional index argument can be specified: const char *con_id, unsigned int idx, enum gpiod_flags flags) +For a more detailed description of the con_id parameter in the DeviceTree case +see Documentation/gpio/board.txt + The flags parameter is used to optionally specify a direction and initial value for the GPIO. Values can be: