From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> commit 1210b17dd4ece454d68a9283f391e3b036aeb010 upstream. [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@xxxxxxx> Reviewed-by: Anthony Koo <Anthony.Koo@xxxxxxx> Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: "Limonciello, Mario" <Mario.Limonciello@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c | 4 ++++ 1 file changed, 4 insertions(+) --- 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 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);
