From patchwork Sun Jan 29 13:24:43 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: John Keeping X-Patchwork-Id: 9544055 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 0A92660488 for ; Sun, 29 Jan 2017 13:33:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F07B027D76 for ; Sun, 29 Jan 2017 13:33:08 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E33B727F88; Sun, 29 Jan 2017 13:33:08 +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 5B49B27D76 for ; Sun, 29 Jan 2017 13:33:08 +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 1cXpbP-0001os-Rh; Sun, 29 Jan 2017 13:33:07 +0000 Received: from casper.infradead.org ([85.118.1.10]) by bombadil.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cXpUJ-0003yL-WF; Sun, 29 Jan 2017 13:25:48 +0000 Received: from dougal.metanate.com ([90.155.101.14] helo=metanate.com) by casper.infradead.org with esmtps (Exim 4.87 #1 (Red Hat Linux)) id 1cXpUC-00055a-2k; Sun, 29 Jan 2017 13:25:46 +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=TlK8n0t+ly40c4v44Am0BMytiWKvjAuD4nkSio/Jej4=; b=V8uArMiEXoz2n7Nkt8yLG4DlJpP/fdUbKk0g1AsQPc1Z2SYiUCPXxEneWSQuaJPtfxl1M8Se35Vu6YCXd87eSZc7CQbfzntusVb8g2jbYcdtdXFPdhTvh2c8FrImCpSCon5r8zb+/HaLnCSPIJe0eClE5NsCj2UqViNOVpsqsy805NUMAilrgJb1oPGAQAXiMmsKm4nd/ueWjQ/kmTJEX9Lk2Ztr0WepNxuh7qfTVSf4Vh23kOUNAbp/hO8FFmN6KeyKzyNXreWtDP2KIbpott5XVU5AMESrPIBOCerVOsEtqU67h0SNMaXyXi6r+JkhaVt/0h9bt0iqgw2qssq78A==; 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 1cXpTo-000362-M6; Sun, 29 Jan 2017 13:25:16 +0000 From: John Keeping To: Mark Yao Subject: [PATCH v3 23/24] drm/rockchip: dw-mipi-dsi: add reset control Date: Sun, 29 Jan 2017 13:24:43 +0000 Message-Id: <20170129132444.25251-24-john@metanate.com> X-Mailer: git-send-email 2.11.0.197.gb556de5.dirty In-Reply-To: <20170129132444.25251-1-john@metanate.com> References: <20170129132444.25251-1-john@metanate.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170129_132540_257222_D662513F X-CRM114-Status: GOOD ( 14.96 ) 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 Reviewed-by: Sean Paul --- v3: - Add Chris' Reviewed-by 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 58cb8ace2fe8..cf3ca6b0cbdb 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 @@ -1124,6 +1125,7 @@ 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; @@ -1162,6 +1164,34 @@ 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__);