drm/radeon: fix check for port PM availability
authorAlex Deucher <alexander.deucher@amd.com>
Mon, 28 Nov 2016 22:23:40 +0000 (17:23 -0500)
committerAlex Deucher <alexander.deucher@amd.com>
Tue, 29 Nov 2016 14:24:13 +0000 (09:24 -0500)
commitbcfdd5d5105087e6f33dfeb08a1ca6b2c0287b61
treebcfa18ced0e36b5a44356096480a750b693a2409
parent7ac33e47d5769632010e537964c7e45498f8dc26
drm/radeon: fix check for port PM availability

The ATPX method does not always exist on the dGPU, it may be located at
the iGPU. The parent device of the iGPU is the root port for which
bridge_d3 is false. This accidentally enables the legacy PM method which
conflicts with port PM and prevented the dGPU from powering on.

Ported from amdgpu commit:
drm/amdgpu: fix check for port PM availability
from Peter Wu.

Fixes: d3ac31f3b4bf9fad (drm/radeon: fix power state when port pm is unavailable (v2))
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Peter Wu <peter@lekensteyn.nl>
Cc: <stable@vger.kernel.org> # 4.8+
drivers/gpu/drm/radeon/radeon_atpx_handler.c