From 80101790670385a85aca35ecae4b89e3f2fceecc Mon Sep 17 00:00:00 2001 From: Alex Deucher Date: Mon, 10 Jun 2013 09:57:07 -0400 Subject: [PATCH] drm/radeon: add backlight quirk for hybrid mac Mac laptops with multiple GPUs apparently use the gmux driver for backlight control. Don't register a radeon backlight interface. We may need to add other pci ids for other hybrid mac laptops. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=65377 Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/radeon/atombios_encoders.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index 8406c825..4120d35 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -186,6 +186,13 @@ void radeon_atom_backlight_init(struct radeon_encoder *radeon_encoder, u8 backlight_level; char bl_name[16]; + /* Mac laptops with multiple GPUs use the gmux driver for backlight + * so don't register a backlight device + */ + if ((rdev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE) && + (rdev->pdev->device == 0x6741)) + return; + if (!radeon_encoder->enc_priv) return; -- 2.7.4