From patchwork Tue Jun 21 07:21:18 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Stein X-Patchwork-Id: 12888743 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 91EB1CCA473 for ; Tue, 21 Jun 2022 07:21:31 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8D59C112719; Tue, 21 Jun 2022 07:21:26 +0000 (UTC) Received: from mx1.tq-group.com (mx1.tq-group.com [93.104.207.81]) by gabe.freedesktop.org (Postfix) with ESMTPS id E2AC71126F2 for ; Tue, 21 Jun 2022 07:21:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1655796085; x=1687332085; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=8xCN16NMVCes5zqwvpgL1iTjCDl7GFfUFwJVxx6Wuk0=; b=cXuWxhyFIHVnQqH7EP1vH/BJT2DqtrWQKRlLQRUHbuBpWVWLl2ti1Zcc MgEMdSDNdoDRF200+Rfbz23a4WG974HISfL+hmN7z4JYmxnJmtIR8crwW iA8CtrdUmv8av6F2ifehpZG+Eaofi87Ffs2UAVs4hnRRX5VQ0K4jgi1db tgtcl6CTC/Ffkdwh3Hs0gyKHNnnYtf7nTfg9Jbt2vDPVK+49l4iTvJf9o WL5UGGrVcV7WtXzS74u8FLcE2qKetq64Mh84utf7vajSjT9PUGHvpVeaJ eQkW9/o3VkSwpAntMpjo1GJ/htESyZn1uoQNK/mrpHTbSw8XwhvLL2WTN w==; X-IronPort-AV: E=Sophos;i="5.92,209,1650924000"; d="scan'208";a="24565786" Received: from unknown (HELO tq-pgp-pr1.tq-net.de) ([192.168.6.15]) by mx1-pgp.tq-group.com with ESMTP; 21 Jun 2022 09:21:22 +0200 Received: from mx1.tq-group.com ([192.168.6.7]) by tq-pgp-pr1.tq-net.de (PGP Universal service); Tue, 21 Jun 2022 09:21:22 +0200 X-PGP-Universal: processed; by tq-pgp-pr1.tq-net.de on Tue, 21 Jun 2022 09:21:22 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tq-group.com; i=@tq-group.com; q=dns/txt; s=key1; t=1655796082; x=1687332082; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=8xCN16NMVCes5zqwvpgL1iTjCDl7GFfUFwJVxx6Wuk0=; b=O6ph/phtBx6MZOjv5ZSlXoP1uptZT5jL01zS2fFWrj9yBw0sseP/c12P bjFPitm1jONSx9BoCigJdBPe2pkpYiT1yLK+Rs4r/6zyPRrqoRdP9Nn70 fwT3fYvKTSpdQQF5ky4RVSzoeHWaVWLKlA7/gAJnDcmsSB4P2yp1/j8HO dXnQum/YiHYt5j8D+AgXGeJz8u3JrwBE0pliCoX27bKjSb+uJlNPLN0gQ e7mNbS5lCNXmMS2+ts7+5ALlYtAYsXiGw39CosMIdFwTetJznjLwJSEtM ItTCmDYfaM37DOz54FhnAaRf9zhHAeFQGN8nh7fgcs2PDKvAGSquXvNon g==; X-IronPort-AV: E=Sophos;i="5.92,209,1650924000"; d="scan'208";a="24565785" Received: from vtuxmail01.tq-net.de ([10.115.0.20]) by mx1.tq-group.com with ESMTP; 21 Jun 2022 09:21:22 +0200 Received: from steina-w.tq-net.de (unknown [10.123.49.12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by vtuxmail01.tq-net.de (Postfix) with ESMTPSA id E0411280056; Tue, 21 Jun 2022 09:21:21 +0200 (CEST) From: Alexander Stein To: Thierry Reding , Sam Ravnborg , David Airlie , Daniel Vetter Subject: [PATCH 1/1] drm/panel: panel-simple: Add dev_err_probe if backlight could not be found Date: Tue, 21 Jun 2022 09:21:18 +0200 Message-Id: <20220621072118.513346-1-alexander.stein@ew.tq-group.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 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: Alexander Stein , dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If the backlight node is not enabled, this (silently) returns with -EPROBE_DEFER. /sys/kernel/debug/devices_deferred also shows nothing helpful: $ cat /sys/kernel/debug/devices_deferred display With this patch, there is a helpful hint: $ cat /sys/kernel/debug/devices_deferred display panel-simple: Could not find backlight Signed-off-by: Alexander Stein --- drivers/gpu/drm/panel/panel-simple.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c index 4a2e580a2f7b..8fb1c563c96a 100644 --- a/drivers/gpu/drm/panel/panel-simple.c +++ b/drivers/gpu/drm/panel/panel-simple.c @@ -663,8 +663,10 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc) drm_panel_init(&panel->base, dev, &panel_simple_funcs, connector_type); err = drm_panel_of_backlight(&panel->base); - if (err) + if (err) { + dev_err_probe(dev, err, "Could not find backlight\n"); goto disable_pm_runtime; + } drm_panel_add(&panel->base);