[PATCH 5.7 025/124] drm/amd/display: Blank stream before destroying HDCP session

Greg Kroah-Hartman
2020-08-24T08:39:40Z

From: Jaehyun Chung <jaehyun.chung@amd.com>

commit 79940e4d10df9c737a394630968471c632246ee0 upstream.

[Why]
Stream disable sequence incorretly destroys HDCP session while stream is
not blanked and while audio is not muted. This sequence causes a flash
of corruption during mode change and an audio click.

[How]
Change sequence to blank stream before destroying HDCP session. Audio will
also be muted by blanking the stream.

Cc: stable@vger.kernel.org
Signed-off-by: Jaehyun Chung <jaehyun.chung@amd.com>
Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@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/core/dc_link.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -3113,12 +3113,11 @@ void core_link_disable_stream(struct pip
dc_is_virtual_signal(pipe_ctx->stream->signal))
return;

+ dc->hwss.blank_stream(pipe_ctx);
#if defined(CONFIG_DRM_AMD_DC_HDCP)
update_psp_stream_config(pipe_ctx, true);
#endif

- dc->hwss.blank_stream(pipe_ctx);
-
if (pipe_ctx->stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST)
deallocate_mst_payload(pipe_ctx);