From patchwork Fri Feb 24 12:55:06 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Keeping X-Patchwork-Id: 9590077 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 7D905601AE for ; Fri, 24 Feb 2017 12:56:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 44C302875B for ; Fri, 24 Feb 2017 12:56:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 39AB228783; Fri, 24 Feb 2017 12:56:39 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C2DCC2875B for ; Fri, 24 Feb 2017 12:56:38 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 845496EC64; Fri, 24 Feb 2017 12:55:52 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from metanate.com (dougal.metanate.com [90.155.101.14]) by gabe.freedesktop.org (Postfix) with ESMTPS id DE8866EC3C for ; Fri, 24 Feb 2017 12:55:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=simple/simple; d=metanate.com; s=stronger; h=References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From; bh=uOIsC1NJjNNlnmN2bjrCEvFLEucxsLtdL93oNKXE7Yg=; b=uok9gB3a4skHEg69oLBGuMatA51YID5Tm03aRPOyBa/m5ecGvMKWFTgoUs1nETbPObH8yL8d8lpbxP3Q6OPhPlCJU6aDPVODSdfOEEws2e8VrTfYmIIyahLXwWgoDsTtubCJOgD+mrpZXmYvUn/x5R+e5qaasAlbb7Or2MzhkRbOYlB8VMeDqJuoSUbek9drpJr06RkP2+6lx6Vc3/GmTv/mlrKISW2jBK+ppMJhzzV04LkCPba36dvfXFNp4k5mxjwbcH3XAWZyHzzp1V/CrOeqjTlFLk8BSW/lpDOOs6FsYKrOK8lLnqaEMdL+EotBc/B/N0irQa2e8dS/UO9TLw==; Received: from brian ([192.168.88.1] helo=leela.metanate.com) by shrek.metanate.com with esmtpsa (TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.83_RC2) (envelope-from ) id 1chFP3-0006ml-4v; Fri, 24 Feb 2017 12:55:17 +0000 From: John Keeping To: Mark Yao Subject: [PATCH v4 23/23] drm/rockchip: dw-mipi-dsi: add reset control Date: Fri, 24 Feb 2017 12:55:06 +0000 Message-Id: <20170224125506.21533-24-john@metanate.com> X-Mailer: git-send-email 2.12.0.rc0.230.gf625d4cdb9.dirty In-Reply-To: <20170224125506.21533-1-john@metanate.com> References: <20170224125506.21533-1-john@metanate.com> Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, Chris Zhong , linux-arm-kernel@lists.infradead.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP In order to fully reset the state of the MIPI controller we must assert this reset. This is slightly more complicated than it could be in order to maintain compatibility with device trees that do not specify the reset property. Signed-off-by: John Keeping Reviewed-by: Chris Zhong --- v4: - Fix error check for devm_reset_control_get() to use ENOENT v3: - Add Chris' Reviewed-by Unchanged in v2 --- drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c index 0c4bae711e84..30da75667334 100644 --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c @@ -13,6 +13,7 @@ #include #include #include +#include #include #include #include @@ -1144,6 +1145,7 @@ static int dw_mipi_dsi_bind(struct device *dev, struct device *master, of_match_device(dw_mipi_dsi_dt_ids, dev); const struct dw_mipi_dsi_plat_data *pdata = of_id->data; struct platform_device *pdev = to_platform_device(dev); + struct reset_control *apb_rst; struct drm_device *drm = data; struct dw_mipi_dsi *dsi; struct resource *res; @@ -1182,6 +1184,35 @@ static int dw_mipi_dsi_bind(struct device *dev, struct device *master, return ret; } + /* + * Note that the reset was not defined in the initial device tree, so + * we have to be prepared for it not being found. + */ + apb_rst = devm_reset_control_get(dev, "apb"); + if (IS_ERR(apb_rst)) { + ret = PTR_ERR(apb_rst); + if (ret == -ENOENT) { + apb_rst = NULL; + } else { + dev_err(dev, "Unable to get reset control: %d\n", ret); + return ret; + } + } + + if (apb_rst) { + ret = clk_prepare_enable(dsi->pclk); + if (ret) { + dev_err(dev, "%s: Failed to enable pclk\n", __func__); + return ret; + } + + reset_control_assert(apb_rst); + usleep_range(10, 20); + reset_control_deassert(apb_rst); + + clk_disable_unprepare(dsi->pclk); + } + ret = clk_prepare_enable(dsi->pllref_clk); if (ret) { dev_err(dev, "%s: Failed to enable pllref_clk\n", __func__);