From: Alex Deucher Date: Mon, 10 Jun 2013 13:57:07 +0000 (-0400) Subject: drm/radeon: add backlight quirk for hybrid mac X-Git-Tag: firefly_0821_release~6453^2~1434 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=5c49b1cfa41e42003b481326af66806e5f1a46b9;p=firefly-linux-kernel-4.4.55.git drm/radeon: add backlight quirk for hybrid mac commit 80101790670385a85aca35ecae4b89e3f2fceecc upstream. 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index 8406c8251fbf..4120d355cadd 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;