@@ -860,6 +860,10 @@ static int drm_atomic_bridge_check(struct drm_bridge *bridge,
struct drm_crtc_state *crtc_state,
struct drm_connector_state *conn_state)
{
+ u8 num_input_lanes, num_output_lanes = 0;
+ const struct drm_lane_cfg *input_lanes;
+ unsigned int i;
+
if (bridge->funcs->atomic_check) {
struct drm_bridge_state *bridge_state;
int ret;
@@ -873,12 +877,25 @@ static int drm_atomic_bridge_check(struct drm_bridge *bridge,
crtc_state, conn_state);
if (ret)
return ret;
+ num_output_lanes = bridge_state->output_bus_cfg.num_lanes;
} else if (bridge->funcs->mode_fixup) {
if (!bridge->funcs->mode_fixup(bridge, &crtc_state->mode,
&crtc_state->adjusted_mode))
return -EINVAL;
}
+ input_lanes = drm_bridge_next_bridge_lane_cfg(bridge,
+ crtc_state->state,
+ &num_input_lanes);
+ /*
+ * Ensure this bridge is aware that the next bridge wants to
+ * reassign lanes.
+ */
+ for (i = 0; i < num_input_lanes; i++) {
+ if (i != input_lanes[i].logical && !num_output_lanes)
+ return -ENOTSUPP;
+ }
+
return 0;
}
Verify during drm_atomic_bridge_check() that the lane assignment set in a bridge's atomic_check() callback is going to be satisfied by the previous bridge. If the next bridge is requiring something besides the default 1:1 lane assignment on its input then there must be an output lane assignment on the previous bridge's output. Otherwise the next bridge won't get the lanes assigned that it needs. Cc: Andrzej Hajda <andrzej.hajda@intel.com> Cc: Neil Armstrong <neil.armstrong@linaro.org> Cc: Robert Foss <rfoss@kernel.org> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com> Cc: Jonas Karlman <jonas@kwiboo.se> Cc: Jernej Skrabec <jernej.skrabec@gmail.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: David Airlie <airlied@gmail.com> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: <dri-devel@lists.freedesktop.org> Cc: Pin-yen Lin <treapking@chromium.org> Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> --- drivers/gpu/drm/drm_bridge.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)