From patchwork Mon Feb 10 12:33:57 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 231680 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 14F6DC3B186 for ; Mon, 10 Feb 2020 13:27:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCCE02082F for ; Mon, 10 Feb 2020 13:27:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581341247; bh=T8sAqA4upVLNUrxAG8sQJk9Le/ePo3ZgUbOsKHbdoFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ns29v0Vwoyo3T9zVmJJip4/4GdWJr98aRpQi0eVvheXyHvgScdgwxi08BMAsbGDpH lWYvQyhIw+umx+y+MoG3TPzRUTAUAih5Y6zhA1OGZ12i5sRWPsmBu+v8UlxH6hqcXZ k+Zyp+As7lclaggkB8qUnqnci5d1s40JmY47VvYc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728541AbgBJN11 (ORCPT ); Mon, 10 Feb 2020 08:27:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:56320 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728442AbgBJMgf (ORCPT ); Mon, 10 Feb 2020 07:36:35 -0500 Received: from localhost (unknown [209.37.97.194]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D253720733; Mon, 10 Feb 2020 12:36:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581338194; bh=T8sAqA4upVLNUrxAG8sQJk9Le/ePo3ZgUbOsKHbdoFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xluJs+1jKBaqnDY3MuyBANwUhTQQPmlSobW9lUORnj3wka71JTWJfZEJAz/8eNBT1 g1PDX/tLSxcSr1F5JlPHZknX9OWta7pUBask72FoKY89bEqJ0BtVb3OAdz+QD9vzZh k0j2tJU+gXo21SAzNHa1/Lzv7mgjWLkkumrP9Qc0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Claudiu Beznea , Sam Ravnborg , Boris Brezillon , Sasha Levin Subject: [PATCH 4.19 179/195] drm: atmel-hlcdc: enable clock before configuring timing engine Date: Mon, 10 Feb 2020 04:33:57 -0800 Message-Id: <20200210122322.706135785@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200210122305.731206734@linuxfoundation.org> References: <20200210122305.731206734@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Claudiu Beznea [ Upstream commit 2c1fb9d86f6820abbfaa38a6836157c76ccb4e7b ] Changing pixel clock source without having this clock source enabled will block the timing engine and the next operations after (in this case setting ATMEL_HLCDC_CFG(5) settings in atmel_hlcdc_crtc_mode_set_nofb() will fail). It is recomended (although in datasheet this is not present) to actually enabled pixel clock source before doing any changes on timing enginge (only SAM9X60 datasheet specifies that the peripheral clock and pixel clock must be enabled before using LCD controller). Fixes: 1a396789f65a ("drm: add Atmel HLCDC Display Controller support") Signed-off-by: Claudiu Beznea Signed-off-by: Sam Ravnborg Cc: Boris Brezillon Cc: # v4.0+ Link: https://patchwork.freedesktop.org/patch/msgid/1576672109-22707-3-git-send-email-claudiu.beznea@microchip.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c index d73281095faca..976109c20d493 100644 --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c @@ -79,7 +79,11 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c) struct videomode vm; unsigned long prate; unsigned int cfg; - int div; + int div, ret; + + ret = clk_prepare_enable(crtc->dc->hlcdc->sys_clk); + if (ret) + return; vm.vfront_porch = adj->crtc_vsync_start - adj->crtc_vdisplay; vm.vback_porch = adj->crtc_vtotal - adj->crtc_vsync_end; @@ -138,6 +142,8 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c) ATMEL_HLCDC_VSPSU | ATMEL_HLCDC_VSPHO | ATMEL_HLCDC_GUARDTIME_MASK | ATMEL_HLCDC_MODE_MASK, cfg); + + clk_disable_unprepare(crtc->dc->hlcdc->sys_clk); } static enum drm_mode_status