From patchwork Thu Nov 15 16:32:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Kocialkowski X-Patchwork-Id: 10684699 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3FE0313BF for ; Thu, 15 Nov 2018 16:34:20 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2CBC828DB7 for ; Thu, 15 Nov 2018 16:34:20 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 20D9C2C942; Thu, 15 Nov 2018 16:34:20 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B463F28DB7 for ; Thu, 15 Nov 2018 16:34:19 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3B03F6E65B; Thu, 15 Nov 2018 16:34:17 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.bootlin.com (mail.bootlin.com [62.4.15.54]) by gabe.freedesktop.org (Postfix) with ESMTP id E4B586E65B for ; Thu, 15 Nov 2018 16:34:15 +0000 (UTC) Received: by mail.bootlin.com (Postfix, from userid 110) id ED4592084B; Thu, 15 Nov 2018 17:34:14 +0100 (CET) Received: from localhost.localdomain (aaubervilliers-681-1-13-146.w90-88.abo.wanadoo.fr [90.88.134.146]) by mail.bootlin.com (Postfix) with ESMTPSA id 3B3D52072C; Thu, 15 Nov 2018 17:33:31 +0100 (CET) From: Paul Kocialkowski To: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH] drm/fb-helper: Blacklist writeback when adding connectors to fbdev Date: Thu, 15 Nov 2018 17:32:48 +0100 Message-Id: <20181115163248.21168-1-paul.kocialkowski@bootlin.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Maxime Ripard , Boris Brezillon , Paul Kocialkowski , David Airlie , Thomas Petazzoni , Sean Paul Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP Writeback connectors do not produce any on-screen output and require special care for use. Such connectors are hidden from enumeration in DRM resources by default, but they are still picked-up by fbdev. This makes rather little sense since fbdev is not really adapted for dealing with writeback. Moreover, this is also a source of issues when userspace disables the CRTC (and associated plane) without detaching the CRTC from the connector (which is hidden by default). In this case, the connector is still using the CRTC, leading to am "enabled/connectors mismatch" and eventually the failure of the associated atomic commit. This situation happens with VC4 testing under IGT GPU Tools. Filter out writeback connectors in the fbdev helper to solve this. Signed-off-by: Paul Kocialkowski Reviewed-by: Boris Brezillon Reviewed-by: Maxime Ripard Tested-by: Maxime Ripard --- drivers/gpu/drm/drm_fb_helper.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index a502f3e519fd..dd852a25d375 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -219,6 +219,9 @@ int drm_fb_helper_single_add_all_connectors(struct drm_fb_helper *fb_helper) mutex_lock(&fb_helper->lock); drm_connector_list_iter_begin(dev, &conn_iter); drm_for_each_connector_iter(connector, &conn_iter) { + if (connector->connector_type == DRM_MODE_CONNECTOR_WRITEBACK) + continue; + ret = __drm_fb_helper_add_one_connector(fb_helper, connector); if (ret) goto fail;