Add a function to get the old MST topology state, required by a follow-up i915 patch.

While at it clarify the code comment of drm_atomic_get_new_mst_topology_state() and add _new prefix to the new state pointer to remind about its difference from the old state.

v2: Use old_/new_ prefixes for the state pointers. (Ville)

Cc: Lyude Paul lyude@redhat.com Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: stable@vger.kernel.org # 6.1 Cc: dri-devel@lists.freedesktop.org Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Imre Deak imre.deak@intel.com --- drivers/gpu/drm/display/drm_dp_mst_topology.c | 33 ++++++++++++++++--- include/drm/display/drm_dp_mst_helper.h | 3 ++ 2 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_mst_topology.c b/drivers/gpu/drm/display/drm_dp_mst_topology.c index 1990ff5dc7ddd..38dab76ae69ea 100644 --- a/drivers/gpu/drm/display/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/display/drm_dp_mst_topology.c @@ -5364,28 +5364,53 @@ struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_a } EXPORT_SYMBOL(drm_atomic_get_mst_topology_state);

+/** + * drm_atomic_get_old_mst_topology_state: get old MST topology state in atomic state, if any + * @state: global atomic state + * @mgr: MST topology manager, also the private object in this case + * + * This function wraps drm_atomic_get_old_private_obj_state() passing in the MST atomic + * state vtable so that the private object state returned is that of a MST + * topology object. + * + * Returns: + * + * The old MST topology state, or NULL if there's no topology state for this MST mgr + * in the global atomic state + */ +struct drm_dp_mst_topology_state * +drm_atomic_get_old_mst_topology_state(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr) +{ + struct drm_private_state *old_priv_state = + drm_atomic_get_old_private_obj_state(state, &mgr->base); + + return old_priv_state ? to_dp_mst_topology_state(old_priv_state) : NULL; +} +EXPORT_SYMBOL(drm_atomic_get_old_mst_topology_state); + /** * drm_atomic_get_new_mst_topology_state: get new MST topology state in atomic state, if any * @state: global atomic state * @mgr: MST topology manager, also the private object in this case * - * This function wraps drm_atomic_get_priv_obj_state() passing in the MST atomic + * This function wraps drm_atomic_get_new_private_obj_state() passing in the MST atomic * state vtable so that the private object state returned is that of a MST * topology object. * * Returns: * - * The MST topology state, or NULL if there's no topology state for this MST mgr + * The new MST topology state, or NULL if there's no topology state for this MST mgr * in the global atomic state */ struct drm_dp_mst_topology_state * drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) { - struct drm_private_state *priv_state = + struct drm_private_state *new_priv_state = drm_atomic_get_new_private_obj_state(state, &mgr->base);

- return priv_state ? to_dp_mst_topology_state(priv_state) : NULL; + return new_priv_state ? to_dp_mst_topology_state(new_priv_state) : NULL; } EXPORT_SYMBOL(drm_atomic_get_new_mst_topology_state);

diff --git a/include/drm/display/drm_dp_mst_helper.h b/include/drm/display/drm_dp_mst_helper.h index f5eb9aa152b14..32c764fb9cb56 100644 --- a/include/drm/display/drm_dp_mst_helper.h +++ b/include/drm/display/drm_dp_mst_helper.h @@ -868,6 +868,9 @@ struct drm_dp_mst_topology_state * drm_atomic_get_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr); struct drm_dp_mst_topology_state * +drm_atomic_get_old_mst_topology_state(struct drm_atomic_state *state, + struct drm_dp_mst_topology_mgr *mgr); +struct drm_dp_mst_topology_state * drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr); struct drm_dp_mst_atomic_payload *