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

[why & how]
Change the order of the pipe_ctx->plane_state check to ensure that
plane_state is not null before accessing it.

Reviewed-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@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 425432c..a68da1a 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
@@ -1932,6 +1932,11 @@ static void dcn20_program_pipe(
            (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)
+               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,
@@ -1939,13 +1944,13 @@ static void dcn20_program_pipe(
                        pipe_ctx->plane_state->lut_bank_a = !pipe_ctx->plane_state->lut_bank_a;
                }
        }
-       if (pipe_ctx->update_flags.bits.enable ||
-           (pipe_ctx->plane_state &&
+       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->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