Commit 204f5573 authored by Alex Hung's avatar Alex Hung Committed by Alex Deucher
Browse files

drm/amd/display: Check returns from drm_dp_dpcd_write 



[WHAT & HOW]
drm_dp_dpcd_write() returns negative error on failure and thus returned
values need to be checked.

This fixes 3 UNUSED_VALUE issues reported by Coverity.

Reviewed-by: default avatarRodrigo Siqueira <rodrigo.siqueira@amd.com>
Signed-off-by: default avatarAlex Hung <alex.hung@amd.com>
Signed-off-by: default avatarRoman Li <roman.li@amd.com>
Tested-by: default avatarDaniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent d25d26b8

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c

+12 −5
Original line number Diff line number Diff line
@@ -643,6 +643,8 @@ static bool execute_synaptics_rc_command(struct drm_dp_aux *aux, 
		// write rc data

		memmove(rc_data, data, length);

		ret = drm_dp_dpcd_write(aux, SYNAPTICS_RC_DATA, rc_data, sizeof(rc_data));

		if (ret < 0)

			goto err;

	}



	// write rc offset
@@ -651,20 +653,21 @@ static bool execute_synaptics_rc_command(struct drm_dp_aux *aux, 
	rc_offset[2] = (unsigned char) (offset >> 16) & 0xFF;

	rc_offset[3] = (unsigned char) (offset >> 24) & 0xFF;

	ret = drm_dp_dpcd_write(aux, SYNAPTICS_RC_OFFSET, rc_offset, sizeof(rc_offset));

	if (ret < 0)

		goto err;



	// write rc length

	rc_length[0] = (unsigned char) length & 0xFF;

	rc_length[1] = (unsigned char) (length >> 8) & 0xFF;

	ret = drm_dp_dpcd_write(aux, SYNAPTICS_RC_LENGTH, rc_length, sizeof(rc_length));

	if (ret < 0)

		goto err;



	// write rc cmd

	rc_cmd = cmd | 0x80;

	ret = drm_dp_dpcd_write(aux, SYNAPTICS_RC_COMMAND, &rc_cmd, sizeof(rc_cmd));



	if (ret < 0) {

		DRM_ERROR("%s: write cmd ..., err = %d\n",  __func__, ret);

		return false;

	}

	if (ret < 0)

		goto err;



	// poll until active is 0

	for (i = 0; i < 10; i++) {
@@ -687,6 +690,10 @@ static bool execute_synaptics_rc_command(struct drm_dp_aux *aux, 
	drm_dbg_dp(aux->drm_dev, "success = %d\n", success);



	return success;



err:

	DRM_ERROR("%s: write cmd ..., err = %d\n",  __func__, ret);

	return false;

}



static void apply_synaptics_fifo_reset_wa(struct drm_dp_aux *aux)