compositor-drm: Cache the DPMS property on drm_output

This avoids one drmModeGetConnector() call every time the DPMS mode is
set. That call can take hundreds of milliseconds due to DDC.

diff --git a/src/compositor-drm.c b/src/compositor-drm.c
index 4222e57..27d4d02 100644 (file)
--- a/src/compositor-drm.c
+++ b/src/compositor-drm.c
@@ -145,6 +145,7 @@ struct drm_output {
        uint32_t connector_id;
        drmModeCrtcPtr original_crtc;
        struct drm_edid edid;
+       drmModePropertyPtr dpms_prop;
 
        int vblank_pending;
        int page_flip_pending;
@@ -1054,6 +1055,8 @@ drm_output_destroy(struct weston_output *output_base)
        if (output->backlight)
                backlight_destroy(output->backlight);
 
+       drmModeFreeProperty(output->dpms_prop);
+
        /* Turn off hardware cursor */
        drmModeSetCursor(c->drm.fd, output->crtc_id, 0, 0, 0);
 
@@ -1365,23 +1368,12 @@ drm_set_dpms(struct weston_output *output_base, enum dpms_enum level)
        struct drm_output *output = (struct drm_output *) output_base;
        struct weston_compositor *ec = output_base->compositor;
        struct drm_compositor *c = (struct drm_compositor *) ec;
-       drmModeConnectorPtr connector;
-       drmModePropertyPtr prop;
 
-       connector = drmModeGetConnector(c->drm.fd, output->connector_id);
-       if (!connector)
+       if (!output->dpms_prop)
                return;
 
-       prop = drm_get_prop(c->drm.fd, connector, "DPMS");
-       if (!prop) {
-               drmModeFreeConnector(connector);
-               return;
-       }
-
-       drmModeConnectorSetProperty(c->drm.fd, connector->connector_id,
-                                   prop->prop_id, level);
-       drmModeFreeProperty(prop);
-       drmModeFreeConnector(connector);
+       drmModeConnectorSetProperty(c->drm.fd, output->connector_id,
+                                   output->dpms_prop->prop_id, level);
 }
 
 static const char *connector_type_names[] = {
@@ -1813,6 +1805,7 @@ create_output_for_connector(struct drm_compositor *ec,
        ec->connector_allocator |= (1 << output->connector_id);
 
        output->original_crtc = drmModeGetCrtc(ec->drm.fd, output->crtc_id);
+       output->dpms_prop = drm_get_prop(ec->drm.fd, connector, "DPMS");
 
        /* Get the current mode on the crtc that's currently driving
         * this connector. */