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 D3541E9B25E for ; Tue, 24 Feb 2026 12:33:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9540410E568; Tue, 24 Feb 2026 12:33:04 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="VKdDBimx"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2051210E568; Tue, 24 Feb 2026 12:33:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1771936383; x=1803472383; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version; bh=rw47ML5VI41EI6n9hBvBEOrn5CJMIRIPb+YWimVZyuU=; b=VKdDBimxRhrdvAYMJ8vktqfV6nArzWZu7jQl7eZ3M8Yk6K9AYMgX0XRm f0iHLBQZhdK6r8iiChtuuDyjgNNOjXPdh+Gy1DM217GhJGgXpZsOBxD5W obBJJlMYH4mkX9He0q82ZwBj1rz2/CbwQSbp/rCxVcQDb4KaoRY9SAlcr M8eUk34kKCKgIESbyc4PPGlM+C/gTTvz27mGa251ESj/iZ9SsF2nxP1HQ RBcDWoCmUJ+EWEmF5AH0rOJplA2OO7wkEGITcoEzIIMs79Zud0EC+KXpI OcGQ5AvP7o6s60lTdPpDQUhIZNaWPQcVVjDYVO+k91neZYZYRZ6zlYvbA g==; X-CSE-ConnectionGUID: q4ODy+nxQ/20bZdo8H63yA== X-CSE-MsgGUID: rypE/ePhS1KMmZOTt5JhAA== X-IronPort-AV: E=McAfee;i="6800,10657,11710"; a="72859865" X-IronPort-AV: E=Sophos;i="6.21,308,1763452800"; d="scan'208";a="72859865" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Feb 2026 04:33:02 -0800 X-CSE-ConnectionGUID: N0E1kfpWRzmg0fLdSdyClQ== X-CSE-MsgGUID: DXpT/57HRJWgE+vIwxAH3w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,308,1763452800"; d="scan'208";a="220882406" Received: from ettammin-mobl2.ger.corp.intel.com (HELO localhost) ([10.245.246.20]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Feb 2026 04:33:00 -0800 From: Jani Nikula To: Suraj Kandpal , intel-xe@lists.freedesktop.org, intel-gfx@lists.freedesktop.org Cc: arun.r.murthy@intel.com, Suraj Kandpal Subject: Re: [PATCH v3 8/8] drm/i915/backlight: Use default/max brightness for INTEL AUX HDR backlight init In-Reply-To: <20260224034526.2730130-9-suraj.kandpal@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs Bertel Jungin Aukio 5, 02600 Espoo, Finland References: <20260224034526.2730130-1-suraj.kandpal@intel.com> <20260224034526.2730130-9-suraj.kandpal@intel.com> Date: Tue, 24 Feb 2026 14:32:57 +0200 Message-ID: <1989e10c76efdbd68bfa550525e828dbb64dbad7@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" On Tue, 24 Feb 2026, Suraj Kandpal wrote: > If the brightness fetched from VBT/previous state is 0 on backlight > initialization, then set the brightness to a default/max value. > Whenever the minimum brightness is reported as 0 there are chances > we maybe sometimes end up with blank screen. This confuses the user > into thinking the display is acting weird. This occurs in eDP 1.4b > when we use proprietary INTEL AUX HDR DPCD registers to manipulate > brightness via luminance values. > > Signed-off-by: Suraj Kandpal > Reviewed-by: Arun R Murthy > --- > v1 -> v2: > - Let users set brightness to 0, make it so that it's just not > done by default (Arun) > > v1 -> v2: > - Update commit header & message (Arun) > > drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > index aac6cdb5b69b..725370bcfa3b 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > @@ -442,6 +442,8 @@ intel_dp_aux_hdr_setup_backlight(struct intel_connector *connector, enum pipe pi > > panel->backlight.level = intel_dp_aux_hdr_get_backlight(connector, pipe); > panel->backlight.enabled = panel->backlight.level != 0; > + if (!panel->backlight.level) > + panel->backlight.level = panel->backlight.max; Same here, .enabled is still based on level != 0 above. > > return 0; > } -- Jani Nikula, Intel