[PATCH 1/4] drm: add vblank hooks to struct drm_crtc_funcs

[Shawn Guo]

From: Shawn Guo <shawn.guo at linaro.org>

The vblank is mostly CRTC specific and implemented as part of CRTC
driver.  So having vblank hooks in struct drm_crtc_funcs should
generally help to reduce code from client drivers in implementing
drm_driver's vblank callbacks.

Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
---
 drivers/gpu/drm/drm_crtc.c | 36 ++++++++++++++++++++++++++++++++++++
 include/drm/drm_crtc.h     | 21 +++++++++++++++++++++
 2 files changed, 57 insertions(+)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 85a7452d0fb4..59ff00f48101 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -70,6 +70,42 @@ struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx)
 EXPORT_SYMBOL(drm_crtc_from_index);
 
 /**
+ * drm_crtc_enable_vblank - vblank enable callback helper
+ * @dev: DRM device
+ * @pipe: CRTC index
+ *
+ * It's a helper function as the generic vblank enable callback implementation,
+ * which calls into &drm_crtc_funcs.enable_vblank function.
+ */
+int drm_crtc_enable_vblank(struct drm_device *dev, unsigned int pipe)
+{
+	struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+
+	if (crtc && crtc->funcs && crtc->funcs->enable_vblank)
+		return crtc->funcs->enable_vblank(crtc);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_crtc_enable_vblank);
+
+/**
+ * drm_crtc_disable_vblank - vblank disable callback helper
+ * @dev: DRM device
+ * @pipe: CRTC index
+ *
+ * It's a helper function as the generic vblank disable callback implementation,
+ * which calls into &drm_crtc_funcs.disable_vblank function.
+ */
+void drm_crtc_disable_vblank(struct drm_device *dev, unsigned int pipe)
+{
+	struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe);
+
+	if (crtc && crtc->funcs && crtc->funcs->disable_vblank)
+		return crtc->funcs->disable_vblank(crtc);
+}
+EXPORT_SYMBOL(drm_crtc_disable_vblank);
+
+/**
  * drm_crtc_force_disable - Forcibly turn off a CRTC
  * @crtc: CRTC to turn off
  *
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index a5627eb8621f..20874b3903a6 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -599,6 +599,25 @@ struct drm_crtc_funcs {
 	 */
 	void (*atomic_print_state)(struct drm_printer *p,
 				   const struct drm_crtc_state *state);
+
+	/**
+	 * @enable_vblank:
+	 *
+	 * Enable vblank interrupts for the CRTC.
+	 *
+	 * Returns:
+	 *
+	 * Zero on success, appropriate errno if the vblank interrupt cannot
+	 * be enabled.
+	 */
+	int (*enable_vblank)(struct drm_crtc *crtc);
+
+	/**
+	 * @disable_vblank:
+	 *
+	 * Disable vblank interrupts for the CRTC.
+	 */
+	void (*disable_vblank)(struct drm_crtc *crtc);
 };
 
 /**
@@ -831,6 +850,8 @@ void drm_crtc_get_hv_timing(const struct drm_display_mode *mode,
 
 int drm_mode_set_config_internal(struct drm_mode_set *set);
 struct drm_crtc *drm_crtc_from_index(struct drm_device *dev, int idx);
+int drm_crtc_enable_vblank(struct drm_device *dev, unsigned int pipe);
+void drm_crtc_disable_vblank(struct drm_device *dev, unsigned int pipe);
 
 /* Helpers */
 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
-- 
1.9.1