From nobody Mon Feb 9 18:45:37 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B37BC001DF for ; Fri, 28 Jul 2023 14:17:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236997AbjG1ORc (ORCPT ); Fri, 28 Jul 2023 10:17:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236973AbjG1ORV (ORCPT ); Fri, 28 Jul 2023 10:17:21 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A28BF3C00 for ; Fri, 28 Jul 2023 07:17:18 -0700 (PDT) Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1qPOHC-0006G5-J8; Fri, 28 Jul 2023 16:17:06 +0200 Received: from [2a0a:edc0:0:1101:1d::39] (helo=dude03.red.stw.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1qPOHA-002jHV-TX; Fri, 28 Jul 2023 16:17:04 +0200 Received: from localhost ([::1] helo=dude03.red.stw.pengutronix.de) by dude03.red.stw.pengutronix.de with esmtp (Exim 4.94.2) (envelope-from ) id 1qPOH9-00APcf-UM; Fri, 28 Jul 2023 16:17:03 +0200 From: Johannes Zink Date: Fri, 28 Jul 2023 16:16:57 +0200 Subject: [PATCH v4 3/3] drm/panel-simple: allow LVDS format override MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20230523-simplepanel_support_nondefault_datamapping-v4-3-e6e7011f34b5@pengutronix.de> References: <20230523-simplepanel_support_nondefault_datamapping-v4-0-e6e7011f34b5@pengutronix.de> In-Reply-To: <20230523-simplepanel_support_nondefault_datamapping-v4-0-e6e7011f34b5@pengutronix.de> To: David Airlie , Daniel Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Laurent Pinchart , Thierry Reding , Neil Armstrong , Sam Ravnborg Cc: kernel test robot , Dan Carpenter , patchwork-jzi@pengutronix.de, kernel@pengutronix.de, Laurent Pinchart , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Johannes Zink X-Mailer: b4 0.12.2 X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: j.zink@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some panels support multiple LVDS data mapping formats, which can be used e.g. run displays on jeida-18 format when only 3 LVDS lanes are available. Add parsing of an optional data-mapping devicetree property, which also touches up the bits per color to match the bus format. Signed-off-by: Johannes Zink --- Changes: v3 -> v4: - worked in Dan's feedback (thanks for reviewing my work): - return with a proper error in case the call to panel_simple_override_nondefault_lvds_datamapping() fails - drop the unneeded and ambiguous ret variable v2 -> v3: - worked in Laurent's review findings (thanks for reviewing my work): - extract fixing up the bus format to separate function - only call function on LVDS panels - fix typos found by Laurent - simplified error handling v1 -> v2: - fix missing unwind goto found by test robot Reported-by: kernel test robot Reported-by: Dan Carpenter Link: https://lore.kernel.org/r/202304160359.4LHmFOlU-lkp@int= el.com/ --- drivers/gpu/drm/panel/panel-simple.c | 53 ++++++++++++++++++++++++++++++++= ++++ 1 file changed, 53 insertions(+) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/p= anel-simple.c index 4badda6570d5..3a164931093e 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -40,6 +40,7 @@ #include #include #include +#include =20 /** * struct panel_desc - Describes a simple panel. @@ -549,6 +550,51 @@ static void panel_simple_parse_panel_timing_node(struc= t device *dev, dev_err(dev, "Reject override mode: No display_timing found\n"); } =20 +static int panel_simple_override_nondefault_lvds_datamapping(struct device= *dev, + struct panel_simple *panel) +{ + int ret, bpc; + + ret =3D drm_of_lvds_get_data_mapping(dev->of_node); + if (ret < 0) { + if (ret =3D=3D -EINVAL) + dev_warn(dev, "Ignore invalid data-mapping property\n"); + + /* + * Ignore non-existing or malformatted property, fallback to + * default data-mapping, and return 0. + */ + return 0; + } + + switch (ret) { + default: + WARN_ON(1); + fallthrough; + case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG: + fallthrough; + case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA: + bpc =3D 8; + break; + case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG: + bpc =3D 6; + } + + if (panel->desc->bpc !=3D bpc || panel->desc->bus_format !=3D ret) { + struct panel_desc *override_desc; + + override_desc =3D devm_kmemdup(dev, panel->desc, sizeof(*panel->desc), G= FP_KERNEL); + if (!override_desc) + return -ENOMEM; + + override_desc->bus_format =3D ret; + override_desc->bpc =3D bpc; + panel->desc =3D override_desc; + } + + return 0; +} + static int panel_simple_probe(struct device *dev, const struct panel_desc = *desc) { struct panel_simple *panel; @@ -601,6 +647,13 @@ static int panel_simple_probe(struct device *dev, cons= t struct panel_desc *desc) panel_simple_parse_panel_timing_node(dev, panel, &dt); } =20 + if (desc->connector_type =3D=3D DRM_MODE_CONNECTOR_LVDS) { + /* Optional data-mapping property for overriding bus format */ + err =3D panel_simple_override_nondefault_lvds_datamapping(dev, panel); + if (err) + goto free_ddc; + } + connector_type =3D desc->connector_type; /* Catch common mistakes for panels. */ switch (connector_type) { --=20 2.39.2