[PATCH 07/12] drm/radeon: disable power control on hybrid laptops

[Alex Deucher]

Windows 10 (and some 8.1) systems use standardized
ACPI calls for hybrid laptops to control dGPU power.
Detect those cases and disable the AMD specific ATPX
power control.

Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
---
 drivers/gpu/drm/radeon/radeon_atpx_handler.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/gpu/drm/radeon/radeon_atpx_handler.c b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
index 95f4fea..3e24fe0 100644
--- a/drivers/gpu/drm/radeon/radeon_atpx_handler.c
+++ b/drivers/gpu/drm/radeon/radeon_atpx_handler.c
@@ -182,6 +182,11 @@ static int radeon_atpx_validate(struct radeon_atpx *atpx)
 				  ATPX_DFP_SIGNAL_MUXED))
 			atpx->functions.disp_mux_cntl = true;
 
+		if (valid_bits & ATPX_MS_HYBRID_GFX_SUPPORTED) {
+			printk("Hybrid Graphics, ATPX dGPU power cntl disabled\n");
+			atpx->functions.power_cntl = false;
+		}
+
 		kfree(info);
 	}
 	return 0;
-- 
2.5.5