From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793745739; b=X9zUEBWcLt4cnrDYrjIp/Z3nqU0LVb9lLjWQ8MxLowKjSOacOdW6ygaJjTURu2edaeOn XJApsXP/6nvJyDXZs5OhgnVR6KemlM6V0WCUAVJhuwb2pwLAUxaFRtEOtfVa+iza6Ftxz EjoX4cKjtOTaHtnGjQu43LVUVO1loG7Irvo08LxBXpy1vRvk1VpjXXGaciUnn+lVxV+Ce Gz09E/91DQnUQDbOTiwvaOJNjnz/Dt1wni60/gupS0ie/8EpiUnTWElUxGI37M+VoFRxL JOmv0yRUK2Y5YM+mUdN6vuowLd59zk1VYd997GrS61FGdTKsmI+JM1mZ/Uw9rDTZdew== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793745739; h=Received:DKIM-Signature:From:Date:Subject:MIME-Version:Content-Type: Content-Transfer-Encoding:Message-Id:References:In-Reply-To:To:Cc: X-Mailer; bh=qVqLMAowWNNhyYo56lksEAIwVw7s3n3V0O+bkJsZopw=; b=FHGXeFItdP/DWrrodFfhSHa1fhe5l3+2aoygCxdRx0MBoL7FNAY53qONvH2Cc01KUfIw K++B7s/+duBv03W7+CC9PVNzSM1sgQ1sTnLX5Qku1VZ3DraQ9lbAKqm4bpvxSSpdqzp72 QnmIAOBUZFr+ppTb20OpPcn2HqwCdDuB132Zfxat2sIKygXkFEJ/tX/oyZvYKM5fztrPu rG5YfbisjXY8VZJf6e6mxk4dkTxW3ggQob+greAyiZJcfjL4L3YJhuG8LLFII5sRVbXHl tDS+ja6gTtmn6fuJyrX1Nwb/1uIoEQYx/0j5i49lwp13XHugUerHIssxCFLM0JJ4kkA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iftOeaxG; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 66F6C606A337 for ; Tue, 3 Nov 2026 22:42:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iftOeaxG Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67A971F00A02; Tue, 3 Nov 2026 22:42:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793745739; bh=qVqLMAowWNNhyYo56lksEAIwVw7s3n3V0O+bkJsZopw=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=iftOeaxGfx9EBOch2JcelLX5nfcthifD4mkbDaBsSwmWLBT/s7L37c3nX/QzFFe6r qC4K7QbarNyv55yrvsV/8cQ7U1LyDD1ifRlTd/ETfHEF6xYGu3Qwo0DxD7LcPFwpu+ PKzvIkHU98UVMtON+Cy9Ut/H4mquUjLPx3x58fJrfIySPPiIkgS02A6DZ+dZ8Lzv6Y lHhuyqz2Zu3LrIR+PUphpC6Sw/8rOWan5Z+K23HsfRdkMvP8iDK6I76jHda42rdmfA F5oWG7NeG6eKljVQHqUNrYo4SytuyJxj7+3t211LL8Ub/+lSRPn6yOy7qgCBox7XZv KZoiaUa9hj8VA== From: "Mario Limonciello (AMD)" Date: Tue, 03 Nov 2026 16:42:03 -0600 Subject: [PATCH v11 02/12] drm/amd/display: Pass up errors reading actual brightness X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261103-superm1-backlight-property-v11-2-00cce7b2ba22@kernel.org> References: <20261103-superm1-backlight-property-v11-0-00cce7b2ba22@kernel.org> In-Reply-To: <20261103-superm1-backlight-property-v11-0-00cce7b2ba22@kernel.org> To: Maxime Ripard , Alex Deucher , Jani Nikula , Javier Martinez Canillas , Maarten Lankhorst , Thomas Zimmermann , David Airlie , Simona Vetter , Harry Wentland , Leo Li , Rodrigo Siqueira Cc: Mario Limonciello , Xaver Hugl , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, nouveau@lists.freedesktop.org, Mario Limonciello X-Mailer: b4 0.16.0 From: Mario Limonciello [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 --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c | 13 +++++++++---- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.h | 2 +- .../amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c | 4 ++-- 3 files changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c index cb74b00723fda..0f664c658a127 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.c @@ -438,7 +438,7 @@ int amdgpu_dm_backlight_update_status(struct backlight_device *bd) EXPORT_IF_KUNIT(amdgpu_dm_backlight_update_status); STATIC_IFN_KUNIT -u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx) +int amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx) { int ret; struct amdgpu_dm_backlight_caps caps; @@ -451,14 +451,14 @@ u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx) 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); } @@ -469,8 +469,13 @@ int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd) { struct amdgpu_display_manager *dm = bl_get_data(bd); int i = amdgpu_dm_backlight_get_device_index(dm, bd); + int ret; + + ret = amdgpu_dm_backlight_get_level(dm, i); + if (ret < 0) + return dm->brightness[i]; - return amdgpu_dm_backlight_get_level(dm, i); + return ret; } EXPORT_IF_KUNIT(amdgpu_dm_backlight_get_brightness); diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.h index 9ad888d3ae7b2..891749322191c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_backlight.h @@ -57,7 +57,7 @@ void amdgpu_dm_validate_backlight_caps(struct amdgpu_display_manager *dm, int bl struct dc_stream_state *dm_find_stream_with_link(struct amdgpu_display_manager *dm, struct dc_link *link); int amdgpu_dm_backlight_update_status(struct backlight_device *bd); -u32 amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx); +int amdgpu_dm_backlight_get_level(struct amdgpu_display_manager *dm, int bl_idx); int amdgpu_dm_backlight_get_brightness(struct backlight_device *bd); ssize_t panel_power_savings_show(struct device *device, struct device_attribute *attr, diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c index 28dda5324dfa7..8fc1c2f997688 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/tests/amdgpu_dm_backlight_test.c @@ -382,7 +382,7 @@ static void dm_test_backlight_get_level_pwm_error(struct kunit *test) dm->brightness[0] = 4321; dm->backlight_link[0] = link; - KUNIT_EXPECT_EQ(test, amdgpu_dm_backlight_get_level(dm, 0), 4321U); + KUNIT_EXPECT_EQ(test, amdgpu_dm_backlight_get_level(dm, 0), -EINVAL); } /** @@ -424,7 +424,7 @@ static void dm_test_backlight_get_level_aux_error(struct kunit *test) caps->caps_valid = true; caps->aux_support = true; - KUNIT_EXPECT_EQ(test, amdgpu_dm_backlight_get_level(dm, 0), 6789U); + KUNIT_EXPECT_EQ(test, amdgpu_dm_backlight_get_level(dm, 0), -EINVAL); } /** -- 2.53.0