From: Gil Fine gil.fine@intel.com
[ Upstream commit 5fd6b9a5cbe63fea4c490fee8af34144a139a266 ]
In case of uni-directional time sync, TMU handshake is initiated by upstream router. In case of bi-directional time sync, TMU handshake is initiated by downstream router. In order to handle correctly the case of uni-directional mode, we avoid changing the upstream router's rate to off, because it might have another downstream router plugged that is set to uni-directional mode (and we don't want to change its mode). Instead, we always change downstream router's rate.
Signed-off-by: Gil Fine gil.fine@intel.com Signed-off-by: Mika Westerberg mika.westerberg@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/thunderbolt/tmu.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/thunderbolt/tmu.c b/drivers/thunderbolt/tmu.c index e4a07a26f693..93ba1d00335b 100644 --- a/drivers/thunderbolt/tmu.c +++ b/drivers/thunderbolt/tmu.c @@ -359,13 +359,14 @@ int tb_switch_tmu_disable(struct tb_switch *sw) * In case of uni-directional time sync, TMU handshake is * initiated by upstream router. In case of bi-directional * time sync, TMU handshake is initiated by downstream router. - * Therefore, we change the rate to off in the respective - * router. + * We change downstream router's rate to off for both uni/bidir + * cases although it is needed only for the bi-directional mode. + * We avoid changing upstream router's mode since it might + * have another downstream router plugged, that is set to + * uni-directional mode and we don't want to change it's TMU + * mode. */ - if (unidirectional) - tb_switch_tmu_rate_write(parent, TB_SWITCH_TMU_RATE_OFF); - else - tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF); + tb_switch_tmu_rate_write(sw, TB_SWITCH_TMU_RATE_OFF);
tb_port_tmu_time_sync_disable(up); ret = tb_port_tmu_time_sync_disable(down);