drm/i915: document why dvo/sdvo/crt need a special dpms function
In the cloned case, changing just one output but keeping the other, the
pipe state won't change and intel_crtc_update_dpms will be a nop, but we
still need to update the dpms state of the output being changed.
Only dvo, sdvo and crt are cloneable, so only those three have special
dpms functions.
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 5e9f93e..3acec8c 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -149,7 +149,7 @@
intel_crt_set_dpms(encoder, crt->connector->base.dpms);
}
-
+/* Special dpms function to support cloning between dvo/sdvo/crt. */
static void intel_crt_dpms(struct drm_connector *connector, int mode)
{
struct drm_device *dev = connector->dev;
@@ -180,6 +180,8 @@
else
encoder->connectors_active = true;
+ /* We call connector dpms manually below in case pipe dpms doesn't
+ * change due to cloning. */
if (mode < old_dpms) {
/* From off to on, enable the pipe first. */
intel_crtc_update_dpms(crtc);