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 EE3D4CD5BD5 for ; Thu, 28 May 2026 05:50:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9595410EC59; Thu, 28 May 2026 05:50:14 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="ZDwOTLG+"; dkim-atps=neutral Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2538910EC56 for ; Thu, 28 May 2026 05:50:09 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 9D28A60126; Thu, 28 May 2026 05:50:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B523E1F000E9; Thu, 28 May 2026 05:50:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779947408; bh=VM1wVLklo1n6ouoG5IwYQhBPuZGvaEU+VXi1kz7PjQQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ZDwOTLG+MxZ8iMzhVGE4STvSvsyRHRYrLrSnQZDFRZ9UKFufo1iKz+NOp5bmVTyuW PhQwZfewETigOk3Y25vcfW+qW+OzcvuvWfpHDBSKtOuZd8OxghQBQYjLaq3u9Ho/+/ 84N2RX73bTuu92GRCXYNAXsrHFKRvynqyTB1XBq2hWEIcaVcMOq0UF0g1WcnJRd6Mr oHBwTDn8tALPRnACII9VhnPLuuHI7HoE/YhtaMPrwpouIgaHuUc9vTk9b0w6NWK0D0 DSMdEQhUOheHXcecX8kjSa3uSUzZ4sMIssHWXvyob2Z9jgfwmnyGefkBvigjtwKj1w c6G6qeIOcVkaA== From: "Mario Limonciello (AMD)" To: dri-devel@lists.freedesktop.org Cc: Mario Limonciello , harry.wentland@amd.com, Louis Chauvet , Dmitry Baryshkov , "Mario Limonciello (AMD)" Subject: [PATCH v4 5/9] drm/amd/display: Pass up errors reading actual brightness Date: Thu, 28 May 2026 00:49:07 -0500 Message-ID: <20260528054911.1513208-6-superm1@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260528054911.1513208-1-superm1@kernel.org> References: <20260528054911.1513208-1-superm1@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" [Why] If the DC API fails to return actual brightness when backlight control API requests it, then the wrong value may be returned. [How] Change return type of amdgpu_dm_backlight_get_level() to an integer and pass an error code up to the caller. Signed-off-by: Mario Limonciello (AMD) --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index c6539e203b92..b6f9188a7b36 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -5441,7 +5441,7 @@ static int amdgpu_dm_backlight_update_status(struct backlight_device *bd) return 0; } -static u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, +static int amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx) { int ret; @@ -5455,14 +5455,14 @@ static u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, u32 avg, peak; if (!dc_link_get_backlight_level_nits(link, &avg, &peak)) - return dm->brightness[bl_idx]; + return -EINVAL; return convert_brightness_to_user(&caps, avg); } ret = dc_link_get_backlight_level(link); if (ret == DC_ERROR_UNEXPECTED) - return dm->brightness[bl_idx]; + return -EINVAL; return convert_brightness_to_user(&caps, ret); } @@ -5470,7 +5470,7 @@ static u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, static int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd) { struct amdgpu_display_manager *dm = bl_get_data(bd); - int i; + int i, ret; for (i = 0; i < dm->num_of_edps; i++) { if (bd == dm->backlight_dev[i]) @@ -5478,7 +5478,12 @@ static int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd) } if (i >= AMDGPU_DM_MAX_NUM_EDP) i = 0; - return amdgpu_dm_backlight_get_level(dm, i); + + ret = amdgpu_dm_backlight_get_level(dm, i); + if (ret < 0) + return dm->brightness[i]; + + return ret; } static const struct backlight_ops amdgpu_dm_backlight_ops = { -- 2.54.0