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 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 2C6C2C00140 for ; Tue, 2 Aug 2022 15:01:10 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 443518DD9B; Tue, 2 Aug 2022 15:01:08 +0000 (UTC) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9FCDC8DD7F for ; Tue, 2 Aug 2022 15:01:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659452462; x=1690988462; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=XzdgkzdGw1FRnZ7+lFZhogk8S2qOyVCriXA0pXhPS2c=; b=A+hJzL/Ko8STK3CaN5fXojUKZW3SgFCb1hEhoksx/9BzFzVhzGZXNhAX krn7A7eqKpR6RfffGZU4UZ7FyU9R6LjQOxgCRjQ7j09KtYmeaj7kOSxBr nMNmnMDLn5NI+nHggf5EsIT14tfmeR0e+dODAGSJeJ7JJ33AlQ2gBu2a5 b/6DRnf5m9RQr16YWILw3Uo4kN25E3ucZgzYMOMWiQf+G92eFjizgVHDK vBjflIWd3ZgPiihibNXQcEzlZ6dIxH8Do2FaNzFOrEArvtZPLXb38asFd aAafnhWz+V8AFp0AgZDWWWAZdwCjVpXT9YN0dSFJgyQeyKQW4c12BMXAO A==; X-IronPort-AV: E=McAfee;i="6400,9594,10427"; a="289439638" X-IronPort-AV: E=Sophos;i="5.93,211,1654585200"; d="scan'208";a="289439638" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Aug 2022 08:01:00 -0700 X-IronPort-AV: E=Sophos;i="5.93,211,1654585200"; d="scan'208";a="661658611" Received: from llaviniu-mobl1.ger.corp.intel.com (HELO localhost) ([10.252.60.134]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Aug 2022 08:00:59 -0700 From: Jani Nikula To: Arun R Murthy , intel-gfx@lists.freedesktop.org In-Reply-To: <20220713081747.1729689-1-arun.r.murthy@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20220602141850.21301-5-animesh.manna@intel.com> <20220713081747.1729689-1-arun.r.murthy@intel.com> Date: Tue, 02 Aug 2022 18:00:56 +0300 Message-ID: <87r11yellj.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Intel-gfx] [PATCHv2] drm/i915/display: add support for dual panel backlight X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Wed, 13 Jul 2022, Arun R Murthy wrote: > The patch with commit 20f85ef89d94 ("drm/i915/backlight: use unique > backlight device names") already adds support for dual panel backlight > but with error prints. Since the patch tried to create the backlight > device with the same name and upon failure will try with a different > name it leads to failure logs in dmesg inturn getting caught by CI. > > This patch alternately will check if the backlight class of same name > exists, will use a different name. > > v2: reworked on top of the patch 20f85ef89d94 ("drm/i915/backlight: use > unique backlight device names") > > Signed-off-by: Arun R Murthy > --- > .../gpu/drm/i915/display/intel_backlight.c | 24 ++++++++----------- > 1 file changed, 10 insertions(+), 14 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_backlight.c b/drivers/gpu/drm/i915/display/intel_backlight.c > index 110fc98ec280..1e550d048e86 100644 > --- a/drivers/gpu/drm/i915/display/intel_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_backlight.c > @@ -971,26 +971,22 @@ int intel_backlight_device_register(struct intel_connector *connector) > if (!name) > return -ENOMEM; > > - bd = backlight_device_register(name, connector->base.kdev, connector, > - &intel_backlight_device_ops, &props); > - > - /* > - * Using the same name independent of the drm device or connector > - * prevents registration of multiple backlight devices in the > - * driver. However, we need to use the default name for backward > - * compatibility. Use unique names for subsequent backlight devices as a > - * fallback when the default name already exists. > - */ > - if (IS_ERR(bd) && PTR_ERR(bd) == -EEXIST) { > + if (backlight_device_get_by_name(name)) { This leaks a reference count to the backlight device. It needs to be something like: bd = backlight_device_get_by_name(name); if (bd) { put_device(&bd->dev); /* ... */ } BR, Jani. > + /* > + * Using the same name independent of the drm device or connector > + * prevents registration of multiple backlight devices in the > + * driver. However, we need to use the default name for backward > + * compatibility. Use unique names for subsequent backlight devices as a > + * fallback when the default name already exists. > + */ > kfree(name); > name = kasprintf(GFP_KERNEL, "card%d-%s-backlight", > i915->drm.primary->index, connector->base.name); > if (!name) > return -ENOMEM; > - > - bd = backlight_device_register(name, connector->base.kdev, connector, > - &intel_backlight_device_ops, &props); > } > + bd = backlight_device_register(name, connector->base.kdev, connector, > + &intel_backlight_device_ops, &props); > > if (IS_ERR(bd)) { > drm_err(&i915->drm, -- Jani Nikula, Intel Open Source Graphics Center