From patchwork Wed Mar 9 15:11:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 12775203 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 877BAC433F5 for ; Wed, 9 Mar 2022 15:16:24 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8719410E596; Wed, 9 Mar 2022 15:16:23 +0000 (UTC) Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by gabe.freedesktop.org (Postfix) with ESMTP id 2E81A10E51A for ; Wed, 9 Mar 2022 15:16:22 +0000 (UTC) X-IronPort-AV: E=Sophos;i="5.90,167,1643641200"; d="scan'208";a="113853373" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie6.idc.renesas.com with ESMTP; 10 Mar 2022 00:11:19 +0900 Received: from localhost.localdomain (unknown [10.226.92.170]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id B7B1B400D0E2; Thu, 10 Mar 2022 00:11:15 +0900 (JST) From: Biju Das To: Andrzej Hajda , Neil Armstrong , Robert Foss , David Airlie , Daniel Vetter Subject: [PATCH 2/2] drm/bridge: adv7533: Add option to disable lane switching Date: Wed, 9 Mar 2022 15:11:09 +0000 Message-Id: <20220309151109.20957-2-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220309151109.20957-1-biju.das.jz@bp.renesas.com> References: <20220309151109.20957-1-biju.das.jz@bp.renesas.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Chris Paterson , Nicolas Boichat , Prabhakar Mahadev Lad , Geert Uytterhoeven , Jonas Karlman , Sia Jee Heng , dri-devel@lists.freedesktop.org, Abhinav Kumar , Jernej Skrabec , Biju Das , linux-renesas-soc@vger.kernel.org, Maxime Ripard , Biju Das , Sam Ravnborg , Laurent Pinchart Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Renesas RZ/{G2L,V2L} platforms changing the lanes from 4 to 3 at lower frequencies causes display instability. On such platforms, it is better to avoid switching lanes from 4 to 3 as it needs different set of PLL parameter constraints to make the display stable with 3 lanes. This patch adds an option to disable lane switching if 'adi,disable-lanes-override' property is present in DT. Signed-off-by: Biju Das Reviewed-by: Lad Prabhakar --- drivers/gpu/drm/bridge/adv7511/adv7511.h | 1 + drivers/gpu/drm/bridge/adv7511/adv7533.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h index 592ecfcf00ca..7505601f10fb 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7511.h +++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h @@ -368,6 +368,7 @@ struct adv7511 { struct mipi_dsi_device *dsi; u8 num_dsi_lanes; bool use_timing_gen; + bool override_lanes; enum adv7511_type type; struct platform_device *audio_pdev; diff --git a/drivers/gpu/drm/bridge/adv7511/adv7533.c b/drivers/gpu/drm/bridge/adv7511/adv7533.c index eb7579dec40a..7f6a8e95d70e 100644 --- a/drivers/gpu/drm/bridge/adv7511/adv7533.c +++ b/drivers/gpu/drm/bridge/adv7511/adv7533.c @@ -108,7 +108,7 @@ void adv7533_mode_set(struct adv7511 *adv, const struct drm_display_mode *mode) if (adv->num_dsi_lanes != 4) return; - if (mode->clock > 80000) + if (!adv->override_lanes || mode->clock > 80000) lanes = 4; else lanes = 3; @@ -195,6 +195,9 @@ int adv7533_parse_dt(struct device_node *np, struct adv7511 *adv) adv->use_timing_gen = !of_property_read_bool(np, "adi,disable-timing-generator"); + adv->override_lanes = !of_property_read_bool(np, + "adi,disable-lanes-override"); + /* TODO: Check if these need to be parsed by DT or not */ adv->rgb = true; adv->embedded_sync = false;