From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, 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 0F337C76186 for ; Tue, 23 Jul 2019 16:55:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5CBF223A0 for ; Tue, 23 Jul 2019 16:55:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390923AbfGWQzz (ORCPT ); Tue, 23 Jul 2019 12:55:55 -0400 Received: from relay2-d.mail.gandi.net ([217.70.183.194]:54927 "EHLO relay2-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390765AbfGWQzy (ORCPT ); Tue, 23 Jul 2019 12:55:54 -0400 X-Originating-IP: 2.224.242.101 Received: from uno.lan (2-224-242-101.ip172.fastwebnet.it [2.224.242.101]) (Authenticated sender: jacopo@jmondi.org) by relay2-d.mail.gandi.net (Postfix) with ESMTPSA id 7A35E40005; Tue, 23 Jul 2019 16:55:49 +0000 (UTC) From: Jacopo Mondi To: Laurent Pinchart , Kieran Bingham , David Airlie , Daniel Vetter , fabrizio.castro@bp.renesas.com Cc: Jacopo Mondi , dri-devel@lists.freedesktop.org (open list:DRM DRIVERS FOR RENESAS), linux-renesas-soc@vger.kernel.org (open list:DRM DRIVERS FOR RENESAS), linux-kernel@vger.kernel.org (open list) Subject: [PATCH] drm: rcar_lvds: Fix dual link mode operations Date: Tue, 23 Jul 2019 18:57:00 +0200 Message-Id: <20190723165700.13124-1-jacopo+renesas@jmondi.org> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The R-Car LVDS encoder units support dual-link operations by splitting the pixel output between the primary encoder and the companion one. In order for the primary encoder to succesfully control the companion's operations this should not fail at probe time and register itself its associated drm bridge so that the primary one can find it. Currently the companion encoder fails at probe time, causing the registration of the primary to fail preventing the whole DU unit to be registered correctly. Fixes: fa440d870358 ("drm: rcar-du: lvds: Add support for dual-link mode") Reported-by: Fabrizio Castro Signed-off-by: Jacopo Mondi --- The "Fixes" tag refers to a patch currently part of the renesas-drivers-2019-07-09-v5.2 branch of Geert's renesas-drivers tree. drivers/gpu/drm/rcar-du/rcar_lvds.c | 31 +++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c index bada7ee98544..8b015ba95895 100644 --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c @@ -767,14 +767,29 @@ static int rcar_lvds_parse_dt(struct rcar_lvds *lvds) of_node_put(remote_input); of_node_put(remote); - /* - * On D3/E3 the LVDS encoder provides a clock to the DU, which can be - * used for the DPAD output even when the LVDS output is not connected. - * Don't fail probe in that case as the DU will need the bridge to - * control the clock. - */ - if (lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL) - return ret == -ENODEV ? 0 : ret; + switch (ret) { + case -ENODEV: + /* + * On D3/E3 the LVDS encoder provides a clock to the DU, which + * can be used for the DPAD output even when the LVDS output is + * not connected. Don't fail probe in that case as the DU will + * need the bridge to control the clock. + */ + if (lvds->info->quirks & RCAR_LVDS_QUIRK_EXT_PLL) + ret = 0; + break; + case -ENXIO: + /* + * When the LVDS output is used in dual link mode, the + * companion encoder fails at + * 'rcar_lvds_parse_dt_companion()'. Don't fail probe in + * that case as the master encoder will need the companion's + * bridge to control its operations. + */ + if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK) + ret = 0; + break; + } return ret; } -- 2.22.0