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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 A3073C4CEC4 for ; Mon, 23 Sep 2019 17:34:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 753D121850 for ; Mon, 23 Sep 2019 17:34:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2502164AbfIWReq (ORCPT ); Mon, 23 Sep 2019 13:34:46 -0400 Received: from muru.com ([72.249.23.125]:34244 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389167AbfIWReq (ORCPT ); Mon, 23 Sep 2019 13:34:46 -0400 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id C7A37809F; Mon, 23 Sep 2019 17:35:16 +0000 (UTC) Date: Mon, 23 Sep 2019 10:34:41 -0700 From: Tony Lindgren To: "H. Nikolaus Schaller" Cc: =?utf-8?Q?Beno=C3=AEt?= Cousson , Rob Herring , Mark Rutland , broonie@kernel.org, linus.walleij@linaro.org, stable@vger.kernel.org, linux-spi@vger.kernel.org, linux-omap@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, letux-kernel@openphoenux.org, kernel@pyra-handheld.com Subject: Re: [PATCH v2] DTS: ARM: gta04: introduce legacy spi-cs-high to make display work again Message-ID: <20190923173441.GV5610@atomide.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * H. Nikolaus Schaller [190920 09:12]: > commit 6953c57ab172 "gpio: of: Handle SPI chipselect legacy bindings" > > did introduce logic to centrally handle the legacy spi-cs-high property > in combination with cs-gpios. This assumes that the polarity > of the CS has to be inverted if spi-cs-high is missing, even > and especially if non-legacy GPIO_ACTIVE_HIGH is specified. > > The DTS for the GTA04 was orginally introduced under the assumption > that there is no need for spi-cs-high if the gpio is defined with > proper polarity GPIO_ACTIVE_HIGH. > > This was not a problem until gpiolib changed the interpretation of > GPIO_ACTIVE_HIGH and missing spi-cs-high. > > The effect is that the missing spi-cs-high is now interpreted as CS being > low (despite GPIO_ACTIVE_HIGH) which turns off the SPI interface when the > panel is to be programmed by the panel driver. > > Therefore, we have to add the redundant and legacy spi-cs-high property > to properly activate CS. Thanks applying into fixes. Tony