From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Alex Deucher Subject: [PATCH 3.17 108/122] drm/radeon: disable native backlight control on pre-r6xx asics (v2) Date: Fri, 5 Dec 2014 14:44:42 -0800 Message-Id: <20141205223322.368751510@linuxfoundation.org> In-Reply-To: <20141205223305.514276242@linuxfoundation.org> References: <20141205223305.514276242@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.17-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alex Deucher commit b7bc596ebbe0cddc97d76ef9309f64471bbf13eb upstream. Just use the acpi interface. That's what windows uses on this generation and it's the only thing that seems to work reliably on these generation parts. You can still force the native backlight interface by setting radeon.backlight=1 Bug: https://bugzilla.kernel.org/show_bug.cgi?id=88501 v2: merge into above if/else block Signed-off-by: Alex Deucher Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/radeon/radeon_encoders.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/radeon/radeon_encoders.c +++ b/drivers/gpu/drm/radeon/radeon_encoders.c @@ -179,6 +179,9 @@ static void radeon_encoder_add_backlight (rdev->pdev->subsystem_vendor == 0x1734) && (rdev->pdev->subsystem_device == 0x1107)) use_bl = false; + /* disable native backlight control on older asics */ + else if (rdev->family < CHIP_R600) + use_bl = false; else use_bl = true; }