soc/intel/tigerlake: Hook up GMA ACPI brightness controls

Add function needed to generate ACPI backlight control SSDT, along with
Kconfig values for accessing the registers.

Tested by adding gfx register on system76/gaze16 and booting Windows.
Display settings has a brightness setting, and can change the brightness
level.

Change-Id: Id8b14c0b4a7a681dc6cb95778c12a006a7e31373
Signed-off-by: Tim Crawford <tcrawford@system76.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57823
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>

1 files changed, 11 insertions, 0 deletions

diff --git a/src/soc/intel/tigerlake/graphics.c b/src/soc/intel/tigerlake/graphics.c
new file mode 100644
index 0000000000..1696d52053
--- /dev/null
+++ b/src/soc/intel/tigerlake/graphics.c
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <intelblocks/graphics.h>
+#include <soc/ramstage.h>
+
+const struct i915_gpu_controller_info *
+intel_igd_get_controller_info(const struct device *const dev)
+{
+	const struct soc_intel_tigerlake_config *const chip = dev->chip_info;
+	return &chip->gfx;
+}