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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 78068C43334 for ; Mon, 3 Sep 2018 17:15:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D7FC20645 for ; Mon, 3 Sep 2018 17:15:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3D7FC20645 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729683AbeICVgi (ORCPT ); Mon, 3 Sep 2018 17:36:38 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:42410 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728676AbeICVgh (ORCPT ); Mon, 3 Sep 2018 17:36:37 -0400 Received: from localhost (ip-213-127-74-90.ip.prioritytelecom.net [213.127.74.90]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 596F4D02; Mon, 3 Sep 2018 17:15:33 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lucas Stach , Philipp Zabel , Sasha Levin Subject: [PATCH 4.14 012/165] drm/imx: imx-ldb: disable LDB on driver bind Date: Mon, 3 Sep 2018 18:54:58 +0200 Message-Id: <20180903165655.622866839@linuxfoundation.org> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180903165655.003605184@linuxfoundation.org> References: <20180903165655.003605184@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lucas Stach [ Upstream commit b58262396fabd43dc869b576e3defdd23b32fe94 ] The LVDS signal integrity is only guaranteed when the correct enable sequence (first IPU DI, then LDB) is used. If the LDB display output was active before the imx-drm driver is loaded (like when a bootsplash was active) the DI will be disabled by the full IPU reset we do when loading the driver. The LDB control registers are not part of the IPU range and thus will remain unchanged. This leads to the LDB still being active when the DI is getting enabled, effectively reversing the required enable sequence. Fix this by also disabling the LDB on driver bind. Signed-off-by: Lucas Stach Signed-off-by: Philipp Zabel Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/imx/imx-ldb.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/imx/imx-ldb.c +++ b/drivers/gpu/drm/imx/imx-ldb.c @@ -612,6 +612,9 @@ static int imx_ldb_bind(struct device *d return PTR_ERR(imx_ldb->regmap); } + /* disable LDB by resetting the control register to POR default */ + regmap_write(imx_ldb->regmap, IOMUXC_GPR2, 0); + imx_ldb->dev = dev; if (of_id)