drm/omap: gem sync: wait on correct events

A waiter of the type OMAP_GEM_READ should wait for a buffer to be completely
written, and only then proceed with reading it. A similar logic applies for
waiters with OMAP_GEM_WRITE flag.

Currently the function is_waiting() waits on the read_complete/read_target
counts in the sync object.

This should be the other way round, as a reader should wait for users who are
'writing' to this buffer, and vice versa.

Make readers of the buffer(OMAP_GEM_READ) wait on the write counters, and
writers to the buffer(OMAP_GEM_WRITE) wait on the read counters in is_waiting()

Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/omap_gem.c

@@ -1047,10 +1047,10 @@ static inline bool is_waiting(struct omap_gem_sync_waiter *waiter)
 {
 	struct omap_gem_object *omap_obj = waiter->omap_obj;
 	if ((waiter->op & OMAP_GEM_READ) &&
-			(omap_obj->sync->read_complete < waiter->read_target))
+			(omap_obj->sync->write_complete < waiter->write_target))
 		return true;
 	if ((waiter->op & OMAP_GEM_WRITE) &&
-			(omap_obj->sync->write_complete < waiter->write_target))
+			(omap_obj->sync->read_complete < waiter->read_target))
 		return true;
 	return false;
 }