4.19-stable review patch. If anyone has any objections, please let me know.
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From: Wesley Chalmers wesley.chalmers@amd.com
commit 3d028d5d60d516c536de1ddd3ebf3d55f3f8983b upstream.
[WHY] Currently, when insert_plane is called with insert_above_mpcc parameter that is equal to tree->opp_list, the function returns NULL.
[HOW] Instead, the function should insert the plane at the top of the tree.
Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Reviewed-by: Jun Lei jun.lei@amd.com Acked-by: Tom Chung chiahsuan.chung@amd.com Signed-off-by: Wesley Chalmers wesley.chalmers@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_mpc.c @@ -193,8 +193,9 @@ struct mpcc *mpc1_insert_plane( /* check insert_above_mpcc exist in tree->opp_list */ struct mpcc *temp_mpcc = tree->opp_list;
- while (temp_mpcc && temp_mpcc->mpcc_bot != insert_above_mpcc) - temp_mpcc = temp_mpcc->mpcc_bot; + if (temp_mpcc != insert_above_mpcc) + while (temp_mpcc && temp_mpcc->mpcc_bot != insert_above_mpcc) + temp_mpcc = temp_mpcc->mpcc_bot; if (temp_mpcc == NULL) return NULL; }