From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932721AbeCIXdB (ORCPT ); Fri, 9 Mar 2018 18:33:01 -0500 Received: from anholt.net ([50.246.234.109]:38324 "EHLO anholt.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932508AbeCIXdA (ORCPT ); Fri, 9 Mar 2018 18:33:00 -0500 From: Eric Anholt To: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org, Eric Anholt , Boris Brezillon Subject: [PATCH] drm/vc4: Fix oops dereferencing DPI's connector since panel_bridge. Date: Fri, 9 Mar 2018 15:32:56 -0800 Message-Id: <20180309233256.1667-1-eric@anholt.net> X-Mailer: git-send-email 2.16.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In the cleanup, I didn't notice that we needed to dereference the connector for the bus_format. Fix the regression by looking up the first (and only) connector attached to us, and assume that its bus_format is what we want. Some day it would be good to have that part of display_info attached to the bridge, instead. Signed-off-by: Eric Anholt Fixes: 7b1298e05310 ("drm/vc4: Switch DPI to using the panel-bridge helper.") Cc: Boris Brezillon --- drivers/gpu/drm/vc4/vc4_dpi.c | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/vc4/vc4_dpi.c b/drivers/gpu/drm/vc4/vc4_dpi.c index 72c9dbd81d7f..88783e143cc2 100644 --- a/drivers/gpu/drm/vc4/vc4_dpi.c +++ b/drivers/gpu/drm/vc4/vc4_dpi.c @@ -96,7 +96,6 @@ struct vc4_dpi { struct platform_device *pdev; struct drm_encoder *encoder; - struct drm_connector *connector; void __iomem *regs; @@ -164,14 +163,31 @@ static void vc4_dpi_encoder_disable(struct drm_encoder *encoder) static void vc4_dpi_encoder_enable(struct drm_encoder *encoder) { + struct drm_device *dev = encoder->dev; struct drm_display_mode *mode = &encoder->crtc->mode; struct vc4_dpi_encoder *vc4_encoder = to_vc4_dpi_encoder(encoder); struct vc4_dpi *dpi = vc4_encoder->dpi; + struct drm_connector_list_iter conn_iter; + struct drm_connector *connector = NULL, *connector_scan; u32 dpi_c = DPI_ENABLE | DPI_OUTPUT_ENABLE_MODE; int ret; - if (dpi->connector->display_info.num_bus_formats) { - u32 bus_format = dpi->connector->display_info.bus_formats[0]; + /* Look up the connector attached to DPI so we can get the + * bus_format. Ideally the bridge would tell us the + * bus_format we want, but it doesn't yet, so assume that it's + * uniform throughout the bridge chain. + */ + drm_connector_list_iter_begin(dev, &conn_iter); + drm_for_each_connector_iter(connector_scan, &conn_iter) { + if (connector_scan->encoder == encoder) { + connector = connector_scan; + break; + } + } + drm_connector_list_iter_end(&conn_iter); + + if (connector && connector->display_info.num_bus_formats) { + u32 bus_format = connector->display_info.bus_formats[0]; switch (bus_format) { case MEDIA_BUS_FMT_RGB888_1X24: @@ -199,6 +215,9 @@ static void vc4_dpi_encoder_enable(struct drm_encoder *encoder) DRM_ERROR("Unknown media bus format %d\n", bus_format); break; } + } else { + /* Default to 24bit if no connector found. */ + dpi_c |= VC4_SET_FIELD(DPI_FORMAT_24BIT_888_RGB, DPI_FORMAT); } if (mode->flags & DRM_MODE_FLAG_NHSYNC) @@ -264,7 +283,7 @@ static int vc4_dpi_init_bridge(struct vc4_dpi *dpi) return ret; } - if (panel) + if (panel) bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI); return drm_bridge_attach(dpi->encoder, bridge, NULL); -- 2.16.2