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 9D9CCC19F28 for ; Wed, 3 Aug 2022 13:33:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A257311BFA0; Wed, 3 Aug 2022 13:33:30 +0000 (UTC) Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by gabe.freedesktop.org (Postfix) with ESMTPS id 080831126AC for ; Wed, 3 Aug 2022 13:33:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659533594; x=1691069594; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=fPNtQevqKUIofDD4nlYXmBB1ZTP/4BEe5KsMA3iecXg=; b=cP5T6IYgPmvchlWD+pWwxptBBCVsfSZHY635tb2MKu2y3+Xw/BVmYBF0 11guLFirt+P+tnEp0wUEXIIqgEuWbrn7lXaMgSF+usy9IymZh5jlFNo8K W/I7BIK9TLxdB2c6OBleOg5km0V1bsnsldBG/v6aQ4BDPNdfVTIOM8cUa bnnm+++Il2Gv4hmiZatu3/WA+TO49DkSvZI50QWsTnk5H2EUM3fV8mB55 kydsBAS7eBt5epmbzFG6C+qCZGNHgIz3cZPpYGKadh+BCPwQy5xpgTG2S +XJKqrDC0hpMW37hja+zwxTDteMA0ffX7AzHwsbrRCvEJVEnUVcJhr+LC g==; X-IronPort-AV: E=McAfee;i="6400,9594,10428"; a="375971210" X-IronPort-AV: E=Sophos;i="5.93,214,1654585200"; d="scan'208";a="375971210" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2022 06:33:12 -0700 X-IronPort-AV: E=Sophos;i="5.93,214,1654585200"; d="scan'208";a="662085051" Received: from ns1-mobl.gar.corp.intel.com (HELO localhost) ([10.252.59.244]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2022 06:33:11 -0700 From: Jani Nikula To: Arun R Murthy , intel-gfx@lists.freedesktop.org In-Reply-To: <20220803100936.2955769-1-arun.r.murthy@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20220803082010.2952698-1-arun.r.murthy@intel.com> <20220803100936.2955769-1-arun.r.murthy@intel.com> Date: Wed, 03 Aug 2022 16:33:09 +0300 Message-ID: <878ro5qwoa.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Intel-gfx] [PATCHv3] 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, 03 Aug 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 commit 20f85ef89d94 > ("drm/i915/backlight: use unique backlight device names") > v3: fixed the ref count leak(Jani N) > > Signed-off-by: Arun R Murthy > --- > .../gpu/drm/i915/display/intel_backlight.c | 27 +++++++++---------- > 1 file changed, 13 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..0f93b2ba907b 100644 > --- a/drivers/gpu/drm/i915/display/intel_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_backlight.c > @@ -971,26 +971,25 @@ 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) { > + bd = backlight_device_get_by_name(name); > + if (bd) { > + put_device(&bd->dev); > + /* > + * 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(bd); Okay, this is getting tedious. Please think about why this kfree is wrong. BR, Jani. > 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