From patchwork Sat Jan 21 16:31:27 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Keeping X-Patchwork-Id: 9530509 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 E9AC2600CA for ; Sat, 21 Jan 2017 16:38:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D90652824F for ; Sat, 21 Jan 2017 16:38:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CBB3528445; Sat, 21 Jan 2017 16:38:33 +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=-1.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, T_DKIM_INVALID autolearn=no version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 86BE52824F for ; Sat, 21 Jan 2017 16:38:33 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cUygS-0007tE-Ul; Sat, 21 Jan 2017 16:38:32 +0000 Received: from merlin.infradead.org ([205.233.59.134]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cUycm-0000QK-VG; Sat, 21 Jan 2017 16:34:45 +0000 Received: from dougal.metanate.com ([90.155.101.14] helo=metanate.com) by merlin.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cUyah-0006pc-MJ; Sat, 21 Jan 2017 16:32:36 +0000 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=u8L9zocJI6UzxusMvZp7UC14IquoTnzR2aNpTQsz/gM=; b=HOoxwd3ebXD8mli1TxN2dFH8ChciarBMWx8SEH/TjxJ7bvgjaL2olmo8PBrjAPJgkaV2//H6ZnuDJiQNM/ZrG1y+uGTbeeDzYI6CiGeyYiEf06ycQzFRJB3PungieLMHmwRqLsuLZemGsjWv472C+7LP/HSRwezXPpmtvi6fxZStxm64kpmKR22MrT55n7TccmkgJl5B13MbFmJsEZmC/mZl0VoW7FnnAv3rDGthY79BpH3nL6/f0DMSbSFsGMkorXi5M9+jDa3/VDPhf1TebV1EhrxeF2pYwHwpmsBWwLEVjDHZwDK6y9pYQTEc3SHkF9havIKkl0ti9XR81JMUmA==; Received: from johnkeeping.plus.com ([81.174.171.191] helo=localhost.localdomain) by shrek.metanate.com with esmtpsa (TLSv1.2:DHE-RSA-AES128-GCM-SHA256:128) (Exim 4.83_RC2) (envelope-from ) id 1cUya8-0004rJ-81; Sat, 21 Jan 2017 16:32:00 +0000 From: John Keeping To: Mark Yao Subject: [PATCH v2 25/26] drm/rockchip: dw-mipi-dsi: add reset control Date: Sat, 21 Jan 2017 16:31:27 +0000 Message-Id: <20170121163128.22240-26-john@metanate.com> X-Mailer: git-send-email 2.11.0.197.gb556de5.dirty In-Reply-To: <20170121163128.22240-1-john@metanate.com> References: <20170121163128.22240-1-john@metanate.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170121_113235_926435_00C5ACF8 X-CRM114-Status: GOOD ( 14.68 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-rockchip@lists.infradead.org, John Keeping , Chris Zhong , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+patchwork-linux-rockchip=patchwork.kernel.org@lists.infradead.org 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 --- Unchanged in v2 --- drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c index 881bb0c62ca5..f780401e8b5e 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 @@ -1121,6 +1122,7 @@ 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; @@ -1159,6 +1161,34 @@ 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)) { + if (PTR_ERR(apb_rst) == -ENODEV) { + apb_rst = NULL; + } else { + dev_err(dev, "Unable to get reset control: %d\n", ret); + return PTR_ERR(apb_rst); + } + } + + 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__);