From 02af01d3192282842384157e15551a7b5ab44999 Mon Sep 17 00:00:00 2001 From: Nicholas Bishop Date: Fri, 11 Feb 2022 14:57:39 -0500 Subject: [PATCH] drm/radeon: Fix backlight control on iMac 12,1 commit 364438fd629f7611a84c8e6d7de91659300f1502 upstream. The iMac 12,1 does not use the gmux driver for backlight, so the radeon backlight device is needed to set the brightness. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1838 Signed-off-by: Nicholas Bishop Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/radeon/atombios_encoders.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/radeon/atombios_encoders.c b/drivers/gpu/drm/radeon/atombios_encoders.c index e67ed383e11b..79aef5c063fa 100644 --- a/drivers/gpu/drm/radeon/atombios_encoders.c +++ b/drivers/gpu/drm/radeon/atombios_encoders.c @@ -193,7 +193,8 @@ void radeon_atom_backlight_init(struct radeon_encoder *radeon_encoder, * so don't register a backlight device */ if ((rdev->pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE) && - (rdev->pdev->device == 0x6741)) + (rdev->pdev->device == 0x6741) && + !dmi_match(DMI_PRODUCT_NAME, "iMac12,1")) return; if (!radeon_encoder->enc_priv) -- 2.20.1