drm/amd/display: Check null pointer before try to access it

[why & how]
Make sure plane_state is not null before calling a function
that dereferences it. Besides, remove redundant codes.

Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
index a68da1a7092d5debbc016843c602a63d3cc4ed44..a80c08582932076333a5ff087f2096e646f612a4 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c
@@ -1928,15 +1928,10 @@ static void dcn20_program_pipe(
            pipe_ctx->stream->update_flags.raw)
                dcn20_update_dchubp_dpp(dc, pipe_ctx, context);
 
-       if (pipe_ctx->update_flags.bits.enable ||
-           (pipe_ctx->plane_state && pipe_ctx->plane_state->update_flags.bits.hdr_mult))
-               hws->funcs.set_hdr_multiplier(pipe_ctx);
-
-       if ((pipe_ctx->plane_state && pipe_ctx->plane_state->update_flags.bits.hdr_mult) ||
-           pipe_ctx->update_flags.bits.enable)
+       if (pipe_ctx->plane_state && (pipe_ctx->update_flags.bits.enable ||
+           pipe_ctx->plane_state->update_flags.bits.hdr_mult))
                hws->funcs.set_hdr_multiplier(pipe_ctx);
 
-
        if (hws->funcs.populate_mcm_luts) {
                if (pipe_ctx->plane_state) {
                        hws->funcs.populate_mcm_luts(dc, pipe_ctx, pipe_ctx->plane_state->mcm_luts,
@@ -1944,13 +1939,12 @@ static void dcn20_program_pipe(
                        pipe_ctx->plane_state->lut_bank_a = !pipe_ctx->plane_state->lut_bank_a;
                }
        }
-       if ((pipe_ctx->plane_state &&
-            pipe_ctx->plane_state->update_flags.bits.in_transfer_func_change) ||
-           (pipe_ctx->plane_state &&
-            pipe_ctx->plane_state->update_flags.bits.gamma_change) ||
-           (pipe_ctx->plane_state &&
-            pipe_ctx->plane_state->update_flags.bits.lut_3d) ||
-            pipe_ctx->update_flags.bits.enable)
+
+       if (pipe_ctx->plane_state &&
+           (pipe_ctx->plane_state->update_flags.bits.in_transfer_func_change ||
+           pipe_ctx->plane_state->update_flags.bits.gamma_change ||
+           pipe_ctx->plane_state->update_flags.bits.lut_3d ||
+           pipe_ctx->update_flags.bits.enable))
                hws->funcs.set_input_transfer_func(dc, pipe_ctx, pipe_ctx->plane_state);
 
        /* dcn10_translate_regamma_to_hw_format takes 750us to finish