drm/irq: Add kms-native crtc interface functions

We need to start somewhere ... With this the only places left in i915
where we use pipe integers is in the interrupt handling code. And
there it actually makes some amount of sense.

v2:
- Polish kerneldoc a bit (Thierry).
- Drop "dev" parameter since it's unecessary.
- Split out i915 changes (Thierry).

Cc: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NDaniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_irq.c

@@ -916,6 +916,8 @@ static int drm_vblank_enable(struct drm_device *dev, int crtc)
  * Acquire a reference count on vblank events to avoid having them disabled
  * while in use.
  *
+ * This is the legacy version of drm_crtc_vblank_get().
+ *
  * Returns:
  * Zero on success, nonzero on failure.
  */
@@ -940,6 +942,24 @@ int drm_vblank_get(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_get);
 
+/**
+ * drm_crtc_vblank_get - get a reference count on vblank events
+ * @crtc: which CRTC to own
+ *
+ * Acquire a reference count on vblank events to avoid having them disabled
+ * while in use.
+ *
+ * This is the native kms version of drm_vblank_off().
+ *
+ * Returns:
+ * Zero on success, nonzero on failure.
+ */
+int drm_crtc_vblank_get(struct drm_crtc *crtc)
+{
+	return drm_vblank_get(crtc->dev, drm_crtc_index(crtc));
+}
+EXPORT_SYMBOL(drm_crtc_vblank_get);
+
 /**
  * drm_vblank_put - give up ownership of vblank events
  * @dev: DRM device
@@ -947,6 +967,8 @@ EXPORT_SYMBOL(drm_vblank_get);
  *
  * Release ownership of a given vblank counter, turning off interrupts
  * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
+ *
+ * This is the legacy version of drm_crtc_vblank_put().
  */
 void drm_vblank_put(struct drm_device *dev, int crtc)
 {
@@ -960,6 +982,21 @@ void drm_vblank_put(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_put);
 
+/**
+ * drm_crtc_vblank_put - give up ownership of vblank events
+ * @crtc: which counter to give up
+ *
+ * Release ownership of a given vblank counter, turning off interrupts
+ * if possible. Disable interrupts after drm_vblank_offdelay milliseconds.
+ *
+ * This is the native kms version of drm_vblank_put().
+ */
+void drm_crtc_vblank_put(struct drm_crtc *crtc)
+{
+	drm_vblank_put(crtc->dev, drm_crtc_index(crtc));
+}
+EXPORT_SYMBOL(drm_crtc_vblank_put);
+
 /**
  * drm_vblank_off - disable vblank events on a CRTC
  * @dev: DRM device
@@ -971,6 +1008,8 @@ EXPORT_SYMBOL(drm_vblank_put);
  *
  * Drivers must use this function when the hardware vblank counter can get
  * reset, e.g. when suspending.
+ *
+ * This is the legacy version of drm_crtc_vblank_off().
  */
 void drm_vblank_off(struct drm_device *dev, int crtc)
 {
@@ -1003,6 +1042,25 @@ void drm_vblank_off(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_off);
 
+/**
+ * drm_crtc_vblank_off - disable vblank events on a CRTC
+ * @crtc: CRTC in question
+ *
+ * Drivers can use this function to shut down the vblank interrupt handling when
+ * disabling a crtc. This function ensures that the latest vblank frame count is
+ * stored so that drm_vblank_on can restore it again.
+ *
+ * Drivers must use this function when the hardware vblank counter can get
+ * reset, e.g. when suspending.
+ *
+ * This is the native kms version of drm_vblank_off().
+ */
+void drm_crtc_vblank_off(struct drm_crtc *crtc)
+{
+	drm_vblank_off(crtc->dev, drm_crtc_index(crtc));
+}
+EXPORT_SYMBOL(drm_crtc_vblank_off);
+
 /**
  * drm_vblank_on - enable vblank events on a CRTC
  * @dev: DRM device
@@ -1012,6 +1070,8 @@ EXPORT_SYMBOL(drm_vblank_off);
  * drm_vblank_off() again. Note that calls to drm_vblank_on() and
  * drm_vblank_off() can be unbalanced and so can also be unconditionaly called
  * in driver load code to reflect the current hardware state of the crtc.
+ *
+ * This is the legacy version of drm_crtc_vblank_on().
  */
 void drm_vblank_on(struct drm_device *dev, int crtc)
 {
@@ -1025,6 +1085,23 @@ void drm_vblank_on(struct drm_device *dev, int crtc)
 }
 EXPORT_SYMBOL(drm_vblank_on);
 
+/**
+ * drm_crtc_vblank_on - enable vblank events on a CRTC
+ * @crtc: CRTC in question
+ *
+ * This functions restores the vblank interrupt state captured with
+ * drm_vblank_off() again. Note that calls to drm_vblank_on() and
+ * drm_vblank_off() can be unbalanced and so can also be unconditionaly called
+ * in driver load code to reflect the current hardware state of the crtc.
+ *
+ * This is the native kms version of drm_vblank_on().
+ */
+void drm_crtc_vblank_on(struct drm_crtc *crtc)
+{
+	drm_vblank_on(crtc->dev, drm_crtc_index(crtc));
+}
+EXPORT_SYMBOL(drm_crtc_vblank_on);
+
 /**
  * drm_vblank_pre_modeset - account for vblanks across mode sets
  * @dev: DRM device

include/drm/drmP.h

@@ -1359,9 +1359,14 @@ extern void drm_send_vblank_event(struct drm_device *dev, int crtc,
 extern bool drm_handle_vblank(struct drm_device *dev, int crtc);
 extern int drm_vblank_get(struct drm_device *dev, int crtc);
 extern void drm_vblank_put(struct drm_device *dev, int crtc);
+extern int drm_crtc_vblank_get(struct drm_crtc *crtc);
+extern void drm_crtc_vblank_put(struct drm_crtc *crtc);
 extern void drm_vblank_off(struct drm_device *dev, int crtc);
 extern void drm_vblank_on(struct drm_device *dev, int crtc);
+extern void drm_crtc_vblank_off(struct drm_crtc *crtc);
+extern void drm_crtc_vblank_on(struct drm_crtc *crtc);
 extern void drm_vblank_cleanup(struct drm_device *dev);
+
 extern u32 drm_get_last_vbltimestamp(struct drm_device *dev, int crtc,
 				     struct timeval *tvblank, unsigned flags);
 extern int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,