[PATCH libdrm v2 2/2] Add CRTC ID to vblank event

[Daniel Stone]

From: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>

When using the atomic API, one request can span multiple CRTCs, however
one event is generated per CRTC. As we cannot disambiguate the CRTC with
user data (since we only have one piece of user data to pass in), newer
kernels can include the CRTC ID in the page flip event.

Add a new vfunc to dispatch vblank events carrying a CRTC ID to clients
who negotiate a higher interface version.

[daniels: Rebased, include new cap, call page_flip_handler if it is set
          but page_flip_handler2 isn't even on newer contexts, write a
	  commit message.]

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira at intel.com>
Signed-off-by: Daniel Stone <daniels at collabora.com>
Cc: Maarten Lankhorst <maarten.lankhorst at intel.com>
---
 xf86drm.h     |  9 ++++++++-
 xf86drmMode.c | 24 ++++++++++++++++--------
 2 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/xf86drm.h b/xf86drm.h
index 0d927018..d75ca8ce 100644
--- a/xf86drm.h
+++ b/xf86drm.h
@@ -728,7 +728,7 @@ extern void drmMsg(const char *format, ...) DRM_PRINTFLIKE(1, 2);
 extern int drmSetMaster(int fd);
 extern int drmDropMaster(int fd);
 
-#define DRM_EVENT_CONTEXT_VERSION 2
+#define DRM_EVENT_CONTEXT_VERSION 3
 
 typedef struct _drmEventContext {
 
@@ -748,6 +748,13 @@ typedef struct _drmEventContext {
 				  unsigned int tv_usec,
 				  void *user_data);
 
+	void (*page_flip_handler2)(int fd,
+				   unsigned int sequence,
+				   unsigned int tv_sec,
+				   unsigned int tv_usec,
+				   unsigned int crtc_id,
+				   void *user_data);
+
 } drmEventContext, *drmEventContextPtr;
 
 extern int drmHandleEvent(int fd, drmEventContextPtr evctx);
diff --git a/xf86drmMode.c b/xf86drmMode.c
index 0266bc10..d3bc20ea 100644
--- a/xf86drmMode.c
+++ b/xf86drmMode.c
@@ -889,6 +889,7 @@ int drmHandleEvent(int fd, drmEventContextPtr evctx)
 	int len, i;
 	struct drm_event *e;
 	struct drm_event_vblank *vblank;
+	void *user_data;
 
 	/* The DRM read semantics guarantees that we always get only
 	 * complete events. */
@@ -915,15 +916,22 @@ int drmHandleEvent(int fd, drmEventContextPtr evctx)
 					      U642VOID (vblank->user_data));
 			break;
 		case DRM_EVENT_FLIP_COMPLETE:
-			if (evctx->version < 2 ||
-			    evctx->page_flip_handler == NULL)
-				break;
 			vblank = (struct drm_event_vblank *) e;
-			evctx->page_flip_handler(fd,
-						 vblank->sequence,
-						 vblank->tv_sec,
-						 vblank->tv_usec,
-						 U642VOID (vblank->user_data));
+			user_data = U642VOID (vblank->user_data);
+
+			if (evctx->version >= 3 && evctx->page_flip_handler2)
+				evctx->page_flip_handler2(fd,
+							 vblank->sequence,
+							 vblank->tv_sec,
+							 vblank->tv_usec,
+							 vblank->crtc_id,
+							 user_data);
+			else if (evctx->version >= 2 && evctx->page_flip_handler)
+				evctx->page_flip_handler(fd,
+							 vblank->sequence,
+							 vblank->tv_sec,
+							 vblank->tv_usec,
+							 user_data);
 			break;
 		default:
 			break;
-- 
2.11.0