From patchwork Tue Jun 9 17:49:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adrian Ratiu X-Patchwork-Id: 199288 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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 2724CC433E4 for ; Tue, 9 Jun 2020 18:21:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 142EB2067B for ; Tue, 9 Jun 2020 18:21:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388962AbgFISVL (ORCPT ); Tue, 9 Jun 2020 14:21:11 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:51740 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732358AbgFIRsl (ORCPT ); Tue, 9 Jun 2020 13:48:41 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: aratiu) with ESMTPSA id E95962A0752 From: Adrian Ratiu To: linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-rockchip@lists.infradead.org, Laurent Pinchart Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Heiko Stuebner , Philippe CORNU , Yannick FERTRE , Jernej Skrabec , Andrzej Hajda , Jonas Karlman , linux-imx@nxp.com, kernel@collabora.com, linux-stm32@st-md-mailman.stormreply.com, Emil Velikov , Adrian Pop , Arnaud Ferraris Subject: [PATCH v9 08/11] drm: stm: dw-mipi-dsi: let the bridge handle the HW version check Date: Tue, 9 Jun 2020 20:49:56 +0300 Message-Id: <20200609174959.955926-9-adrian.ratiu@collabora.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200609174959.955926-1-adrian.ratiu@collabora.com> References: <20200609174959.955926-1-adrian.ratiu@collabora.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The stm mipi-dsi platform driver added a version test in commit fa6251a747b7 ("drm/stm: dsi: check hardware version") so that HW revisions other than v1.3x get rejected. The rockchip driver had no such check and just assumed register layouts are v1.3x compatible. Having such tests was a good idea because only v130/v131 layouts were supported at the time, however since adding multiple layout support in the bridge, the version is automatically checked for all drivers, compatible layouts get picked and unsupported HW is automatically rejected by the bridge, so there's no use keeping the test in the stm driver. The main reason prompting this change is that the stm driver test immediately disabled the peripheral clock after reading the version, making the bridge read version 0x0 immediately after in its own probe(), so we move the clock disabling after the bridge does the version test. Tested on STM32F769 and STM32MP1. Cc: linux-stm32@st-md-mailman.stormreply.com Cc: Emil Velikov Reported-by: Adrian Pop Tested-by: Adrian Pop Tested-by: Arnaud Ferraris Signed-off-by: Adrian Ratiu --- New in v6. --- drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c index 2e1f2664495d0..45f67f8a5f6c8 100644 --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c @@ -396,26 +396,19 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev) goto err_dsi_probe; } + /* enable pclk so MMIO register values can be read, else reads == 0x0 */ ret = clk_prepare_enable(pclk); if (ret) { DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__); goto err_dsi_probe; } - dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION; - clk_disable_unprepare(pclk); - - if (dsi->hw_version != HWVER_130 && dsi->hw_version != HWVER_131) { - ret = -ENODEV; - DRM_ERROR("bad dsi hardware version\n"); - goto err_dsi_probe; - } - dw_mipi_dsi_stm_plat_data.base = dsi->base; dw_mipi_dsi_stm_plat_data.priv_data = dsi; platform_set_drvdata(pdev, dsi); + /* setup the bridge, this will also access MMIO registers via regmap */ dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data); if (IS_ERR(dsi->dsi)) { ret = PTR_ERR(dsi->dsi); @@ -423,6 +416,11 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev) goto err_dsi_probe; } + dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION; + + /* initial MMIO config done, disable clk to save power */ + clk_disable_unprepare(pclk); + return 0; err_dsi_probe: