drm: Add dev->vblank_disable_immediate flag
Add a flag to drm_device which will cause the vblank code to bypass the
disable timer and always disable the vblank interrupt immediately when
the last reference is dropped.
v2: Add some notes about the flag to the kernel doc
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl
index 55923d0..583edbf 100644
--- a/Documentation/DocBook/drm.tmpl
+++ b/Documentation/DocBook/drm.tmpl
@@ -3387,6 +3387,12 @@
module parameter or the <varname>drm_vblank_offdelay</varname> global
variable and expressed in milliseconds. Its default value is 5000 ms.
Zero means never disable, and a negative value means disable immediately.
+ Drivers may override the behaviour by setting the
+ <structname>drm_device</structname>
+ <structfield>vblank_disable_immediate</structfield> flag, which when set
+ causes vblank interrupts to be disabled immediately regardless of the
+ drm_vblank_offdelay value. The flag should only be set if there's a
+ properly working hardware vblank counter present.
</para>
<para>
When a vertical blanking interrupt occurs drivers only need to call the