drm/i915: Add new GET_PIPE_FROM_CRTC_ID ioctl.
This allows userlevel code to discover the pipe number corresponding
to a given CRTC ID. This is necessary for doing pipe-specific
operations such as waiting for vblank on a given CRTC. Failure to use
the right pipe mapping can result in GPU hangs, or at least failure
to actually sync to vblank.
Signed-off-by: Carl Worth <cworth@cworth.org>
[anholt: Style touchups from review]
Signed-off-by: Eric Anholt <eric@anholt.net>
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index cf29430..cd4b9c5 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -125,6 +125,8 @@
extern struct drm_display_mode *intel_crtc_mode_get(struct drm_device *dev,
struct drm_crtc *crtc);
+int intel_get_pipe_from_crtc_id(struct drm_device *dev, void *data,
+ struct drm_file *file_priv);
extern void intel_wait_for_vblank(struct drm_device *dev);
extern struct drm_crtc *intel_get_crtc_from_pipe(struct drm_device *dev, int pipe);
extern struct drm_crtc *intel_get_load_detect_pipe(struct intel_output *intel_output,