drm/amdgpu: Add amdgpu "max bpc" connector property (v2)
commita0c25b4098b8de23f34f81860ddc3cbaaa159189
authorNicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Thu, 15 Nov 2018 22:19:12 +0000 (15 17:19 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 13 Dec 2018 08:16:12 +0000 (13 09:16 +0100)
treec8098ae6da23ee385c684508748529f550ac1af9
parent12163e3e69020fa409110a00fffbfd4c8969df2c
drm/amdgpu: Add amdgpu "max bpc" connector property (v2)

[ Upstream commit 69756c6ff0de478c10100481f16c966dde3b5339 ]

[Why]
Many panels support more than 8bpc but some modes are unavailable while
running at greater than 8bpc due to DP/HDMI bandwidth constraints.

Support for more than 8bpc was added recently in the driver but it
defaults to the maximum supported bpc - locking out these modes.

This should be a user configurable option such that the user can select
what bpc configuration they would like.

[How]
This patch introduces the "max bpc" amdgpu driver specific connector
property so the user can limit the maximum bpc. It ranges from 8 to 16.

This doesn't directly set the preferred bpc for the panel since it
follows Intel's existing driver conventions.

This proprety should be removed once common drm support for max bpc
lands.

v2: rebase on upstream (Alex)

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h