From patchwork Mon Jul 17 06:18:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liu Ying X-Patchwork-Id: 13316397 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail-am6eur05on2061c.outbound.protection.outlook.com ([2a01:111:f400:7e1b::61c] helo=EUR05-AM6-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qLHjj-0039G4-2X for linux-arm-kernel@lists.infradead.org; Mon, 17 Jul 2023 06:29:38 +0000 From: Liu Ying Subject: [PATCH 3/9] drm/bridge: synopsys: dw-mipi-dsi: Force input bus flags Date: Mon, 17 Jul 2023 14:18:25 +0800 Message-Id: <20230717061831.1826878-4-victor.liu@nxp.com> In-Reply-To: <20230717061831.1826878-1-victor.liu@nxp.com> References: <20230717061831.1826878-1-victor.liu@nxp.com> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+lwn-linux-arm-kernel=archive.lwn.net@lists.infradead.org List-Archive: To: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, airlied@gmail.com, daniel@ffwll.ch, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com The DATAEN_ACTIVE_LOW bit in DSI_DPI_CFG_POL register is set to zero, so set the DRM_BUS_FLAG_DE_HIGH flag in input_bus_cfg.flags. It appears that the DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE flag also makes sense, so set it in input_bus_cfg.flags too. With this patch, the flags set by drm_atomic_bridge_propagate_bus_flags() are overridden (see comment in that function) in case any downstream bridges propagates invalid flags to this bridge. A real problematic case is to connect a RM67191 MIPI DSI panel whose driver sets DRM_BUS_FLAG_DE_LOW and DRM_BUS_FLAG_PIXDATA_SAMPLE_POSEDGE bus flags. Signed-off-by: Liu Ying --- drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c index 8580b8a97fb1..8cd89a63b5f2 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -565,6 +566,17 @@ dw_mipi_dsi_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge, return input_fmts; } +static int dw_mipi_dsi_bridge_atomic_check(struct drm_bridge *bridge, + struct drm_bridge_state *bridge_state, + struct drm_crtc_state *crtc_state, + struct drm_connector_state *conn_state) +{ + bridge_state->input_bus_cfg.flags = + DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE; + + return 0; +} + static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi) { u32 val; @@ -1033,6 +1045,7 @@ static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = { .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state, .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state, .atomic_get_input_bus_fmts = dw_mipi_dsi_bridge_atomic_get_input_bus_fmts, + .atomic_check = dw_mipi_dsi_bridge_atomic_check, .atomic_reset = drm_atomic_helper_bridge_reset, .atomic_enable = dw_mipi_dsi_bridge_atomic_enable, .atomic_post_disable = dw_mipi_dsi_bridge_post_atomic_disable,