drm/amd/display: Only set PSR version when valid

[Why]
DMCUB will hang if we send a PSR unsupported set version command.

This can occur if we fall-through into the default case in the switch
statement for PSR version.

[How]
Add an unsupported check after the switch statement.

Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
index 87ed48d5530dc7b51507350d26d0f8f2bc4efa40..8bd265b40847076999456edf6c504e39f141bb0e 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
@@ -138,6 +138,10 @@ static bool dmub_psr_set_version(struct dmub_psr *dmub, struct dc_stream_state *
                cmd.psr_set_version.psr_set_version_data.version = PSR_VERSION_UNSUPPORTED;
                break;
        }
+
+       if (cmd.psr_set_version.psr_set_version_data.version == PSR_VERSION_UNSUPPORTED)
+               return false;
+
        cmd.psr_set_version.psr_set_version_data.cmd_version = DMUB_CMD_PSR_CONTROL_VERSION_1;
        cmd.psr_set_version.psr_set_version_data.panel_inst = panel_inst;
        cmd.psr_set_version.header.payload_bytes = sizeof(struct dmub_cmd_psr_set_version_data);