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=-2.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY,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 15C52C433F5 for ; Wed, 5 Sep 2018 08:32:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC184206BA for ; Wed, 5 Sep 2018 08:32:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC184206BA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mediatek.com 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 S1727988AbeIENBU (ORCPT ); Wed, 5 Sep 2018 09:01:20 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:33337 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726401AbeIENBT (ORCPT ); Wed, 5 Sep 2018 09:01:19 -0400 X-UUID: d76c9947260b406eb270bb21b65a0f93-20180905 Received: from mtkcas07.mediatek.inc [(172.21.101.84)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 482850902; Wed, 05 Sep 2018 16:32:07 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Wed, 5 Sep 2018 16:31:48 +0800 Received: from mtkslt209.mediatek.inc (10.21.15.96) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1210.3 via Frontend Transport; Wed, 5 Sep 2018 16:31:48 +0800 From: Bibby Hsieh To: David Airlie , Matthias Brugger , Daniel Vetter , , CC: Yingjoe Chen , Cawa Cheng , Daniel Kurtz , Bibby Hsieh , Philipp Zabel , YT Shen , Thierry Reding , CK Hu , Mao Huang , , , Sascha Hauer , chunhui dai Subject: [PATCH v2 01/13] drm/mediatek: add refcount for DPI power on/off Date: Wed, 5 Sep 2018 16:31:34 +0800 Message-ID: <20180905083146.14727-2-bibby.hsieh@mediatek.com> X-Mailer: git-send-email 2.12.5.2.gbdf23ab In-Reply-To: <20180905083146.14727-1-bibby.hsieh@mediatek.com> References: <20180905083146.14727-1-bibby.hsieh@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: chunhui dai add refcount for DPI power on/off to protect the flow Signed-off-by: chunhui dai --- drivers/gpu/drm/mediatek/mtk_dpi.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c b/drivers/gpu/drm/mediatek/mtk_dpi.c index 6c0ea39d5739..d9373e67d328 100644 --- a/drivers/gpu/drm/mediatek/mtk_dpi.c +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c @@ -77,6 +77,7 @@ struct mtk_dpi { enum mtk_dpi_out_bit_num bit_num; enum mtk_dpi_out_channel_swap channel_swap; bool power_sta; + int refcount; u8 power_ctl; }; @@ -369,6 +370,12 @@ static void mtk_dpi_config_color_format(struct mtk_dpi *dpi, static void mtk_dpi_power_off(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) { + if (WARN_ON(dpi->refcount == 0)) + return; + + if (--dpi->refcount != 0) + return; + dpi->power_ctl &= ~pctl; if ((dpi->power_ctl & DPI_POWER_START) || @@ -388,14 +395,17 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) { int ret; + if (++dpi->refcount != 1) + return 0; + dpi->power_ctl |= pctl; if (!(dpi->power_ctl & DPI_POWER_START) && !(dpi->power_ctl & DPI_POWER_ENABLE)) - return 0; + goto err_refcount; if (dpi->power_sta) - return 0; + goto err_refcount; ret = clk_prepare_enable(dpi->engine_clk); if (ret) { @@ -417,6 +427,8 @@ static int mtk_dpi_power_on(struct mtk_dpi *dpi, enum mtk_dpi_power_ctl pctl) clk_disable_unprepare(dpi->engine_clk); err_eng: dpi->power_ctl &= ~pctl; +err_refcount: + dpi->refcount--; return ret; } -- 2.12.5.2.gbdf23ab