Commit 886571d2 authored by Srinivasan Shanmugam's avatar Srinivasan Shanmugam Committed by Alex Deucher
Browse files

drm/amd/display: Fix 'panel_cntl' could be null in 'dcn21_set_backlight_level()' 



'panel_cntl' structure used to control the display panel could be null,
dereferencing it could lead to a null pointer access.

Fixes the below:
drivers/gpu/drm/amd/amdgpu/../display/dc/hwss/dcn21/dcn21_hwseq.c:269 dcn21_set_backlight_level() error: we previously assumed 'panel_cntl' could be null (see line 250)

Fixes: 474ac4a8 ("drm/amd/display: Implement some asic specific abm call backs.")
Cc: Yongqiang Sun <yongqiang.sun@amd.com>
Cc: Anthony Koo <Anthony.Koo@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: default avatarSrinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: default avatarAnthony Koo <Anthony.Koo@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent fb38ad0a

drivers/gpu/drm/amd/display/dc/hwss/dcn21/dcn21_hwseq.c

+20 −19
Original line number Diff line number Diff line
@@ -237,17 +237,20 @@ bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx, 
{

	struct dc_context *dc = pipe_ctx->stream->ctx;

	struct abm *abm = pipe_ctx->stream_res.abm;

	struct timing_generator *tg = pipe_ctx->stream_res.tg;

	struct panel_cntl *panel_cntl = pipe_ctx->stream->link->panel_cntl;

	uint32_t otg_inst;



	if (!abm && !tg && !panel_cntl)

		return false;



	otg_inst = tg->inst;



	if (dc->dc->res_pool->dmcu) {

		dce110_set_backlight_level(pipe_ctx, backlight_pwm_u16_16, frame_ramp);

		return true;

	}



	if (abm != NULL) {

		uint32_t otg_inst = pipe_ctx->stream_res.tg->inst;



		if (abm && panel_cntl) {

	if (abm->funcs && abm->funcs->set_pipe_ex) {

		abm->funcs->set_pipe_ex(abm,

					otg_inst,
@@ -261,10 +264,8 @@ bool dcn21_set_backlight_level(struct pipe_ctx *pipe_ctx, 
				  panel_cntl->inst,

				  panel_cntl->pwrseq_inst);

	}

		}

	}



	if (abm && abm->funcs && abm->funcs->set_backlight_level_pwm)

	if (abm->funcs && abm->funcs->set_backlight_level_pwm)

		abm->funcs->set_backlight_level_pwm(abm, backlight_pwm_u16_16,

			frame_ramp, 0, panel_cntl->inst);

	else