From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 805D3AD38 for ; Wed, 4 Jan 2023 16:10:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1CB0C433F0; Wed, 4 Jan 2023 16:10:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672848635; bh=59SvUcSmaASt14zvlSbB04zfzDQcW3y2jq00V/IEwJs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QF7ELPGGGpoYe1KY15oP65RaBta0Asop0yBt4xWO4MNvJoSo2xujqwRamKUzGVh9C rru+Mire0s/5CgnoWEBIQf4qclXoDUb80QswAgBE/cNrxg9UOJiiUR4UUYy8lHwsrQ v/t0HlWZtCtidsfENzQgWG16tqdnNuuV0BzQ2Flw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hans de Goede , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 6.1 046/207] ACPI: video: Simplify __acpi_video_get_backlight_type() Date: Wed, 4 Jan 2023 17:05:04 +0100 Message-Id: <20230104160513.373492984@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230104160511.905925875@linuxfoundation.org> References: <20230104160511.905925875@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Hans de Goede [ Upstream commit a5df42521f328b45c9d89c13740e747be08ac66e ] Simplify __acpi_video_get_backlight_type() removing a nested if which makes the flow harder to follow. This also results in having only 1 exit point with return acpi_backlight_native instead of 2. Note this drops the (video_caps & ACPI_VIDEO_BACKLIGHT) check from the if (acpi_osi_is_win8() && native_available) return native path. Windows 8's hardware certification requirements include that there must be ACPI video bus backlight control, so the ACPI_VIDEO_BACKLIGHT check is redundant. Signed-off-by: Hans de Goede Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/video_detect.c | 36 +++++++++++++++++------------------- 1 file changed, 17 insertions(+), 19 deletions(-) diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c index 13f10fbcd7f0..0c17ee93f861 100644 --- a/drivers/acpi/video_detect.c +++ b/drivers/acpi/video_detect.c @@ -734,6 +734,16 @@ static bool google_cros_ec_present(void) return acpi_dev_found("GOOG0004") || acpi_dev_found("GOOG000C"); } +/* + * Windows 8 and newer no longer use the ACPI video interface, so it often + * does not work. So on win8+ systems prefer native brightness control. + * Chromebooks should always prefer native backlight control. + */ +static bool prefer_native_over_acpi_video(void) +{ + return acpi_osi_is_win8() || google_cros_ec_present(); +} + /* * Determine which type of backlight interface to use on this system, * First check cmdline, then dmi quirks, then do autodetect. @@ -779,26 +789,14 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native) if (apple_gmux_backlight_present()) return acpi_backlight_apple_gmux; - /* Chromebooks should always prefer native backlight control. */ - if (google_cros_ec_present() && native_available) - return acpi_backlight_native; + /* Use ACPI video if available, except when native should be preferred. */ + if ((video_caps & ACPI_VIDEO_BACKLIGHT) && + !(native_available && prefer_native_over_acpi_video())) + return acpi_backlight_video; - /* On systems with ACPI video use either native or ACPI video. */ - if (video_caps & ACPI_VIDEO_BACKLIGHT) { - /* - * Windows 8 and newer no longer use the ACPI video interface, - * so it often does not work. If the ACPI tables are written - * for win8 and native brightness ctl is available, use that. - * - * The native check deliberately is inside the if acpi-video - * block on older devices without acpi-video support native - * is usually not the best choice. - */ - if (acpi_osi_is_win8() && native_available) - return acpi_backlight_native; - else - return acpi_backlight_video; - } + /* Use native if available */ + if (native_available && prefer_native_over_acpi_video()) + return acpi_backlight_native; /* No ACPI video (old hw), use vendor specific fw methods. */ return acpi_backlight_vendor; -- 2.35.1