[PATCH 14/23] drm: omapdrm: Keep vblank interrupt enabled while CRTC is active

[Laurent Pinchart]

Instead of going through a complicated private IRQ registration
mechanism, handle the vblank interrupt activation with the standard
drm_crtc_vblank_get() and drm_crtc_vblank_put() mechanism. This will let
the DRM core keep the vblank interrupt enabled as long as needed to
update the frame counter.

Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 drivers/gpu/drm/omapdrm/omap_crtc.c | 38 ++++++++++++++-----------------------
 drivers/gpu/drm/omapdrm/omap_drv.h  |  1 +
 drivers/gpu/drm/omapdrm/omap_irq.c  |  4 +++-
 3 files changed, 18 insertions(+), 25 deletions(-)

diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c
index ee744ab6608c..3265cd990acf 100644
--- a/drivers/gpu/drm/omapdrm/omap_crtc.c
+++ b/drivers/gpu/drm/omapdrm/omap_crtc.c
@@ -36,8 +36,6 @@ struct omap_crtc {
 
 	struct omap_video_timings timings;
 
-	struct omap_drm_irq vblank_irq;
-
 	bool ignore_digit_sync_lost;
 
 	bool pending;
@@ -302,25 +300,24 @@ void omap_crtc_error_irq(struct drm_crtc *crtc, uint32_t irqstatus)
 	DRM_ERROR_RATELIMITED("%s: errors: %08x\n", omap_crtc->name, irqstatus);
 }
 
-static void omap_crtc_vblank_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
+void omap_crtc_vblank_irq(struct drm_crtc *crtc)
 {
-	struct omap_crtc *omap_crtc =
-			container_of(irq, struct omap_crtc, vblank_irq);
-	struct drm_device *dev = omap_crtc->base.dev;
-	struct drm_crtc *crtc = &omap_crtc->base;
+	struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
+	bool pending;
 
 	if (dispc_mgr_go_busy(omap_crtc->channel))
 		return;
 
 	DBG("%s: apply done", omap_crtc->name);
 
-	__omap_irq_unregister(dev, &omap_crtc->vblank_irq);
-
 	spin_lock(&crtc->dev->event_lock);
-	WARN_ON(!omap_crtc->pending);
+	pending = omap_crtc->pending;
 	omap_crtc->pending = false;
 	spin_unlock(&crtc->dev->event_lock);
 
+	if (pending)
+		drm_crtc_vblank_put(crtc);
+
 	/* wake up userspace */
 	omap_crtc_complete_page_flip(&omap_crtc->base);
 
@@ -338,8 +335,6 @@ static void omap_crtc_destroy(struct drm_crtc *crtc)
 
 	DBG("%s", omap_crtc->name);
 
-	WARN_ON(omap_crtc->vblank_irq.registered);
-
 	drm_crtc_cleanup(crtc);
 
 	kfree(omap_crtc);
@@ -351,14 +346,13 @@ static void omap_crtc_enable(struct drm_crtc *crtc)
 
 	DBG("%s", omap_crtc->name);
 
+	drm_crtc_vblank_on(crtc);
+	WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+
 	spin_lock_irq(&crtc->dev->event_lock);
 	WARN_ON(omap_crtc->pending);
 	omap_crtc->pending = true;
 	spin_unlock_irq(&crtc->dev->event_lock);
-
-	omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);
-
-	drm_crtc_vblank_on(crtc);
 }
 
 static void omap_crtc_disable(struct drm_crtc *crtc)
@@ -406,8 +400,6 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
 {
 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
 
-	WARN_ON(omap_crtc->vblank_irq.registered);
-
 	/*
 	 * Only flush the CRTC if it is currently active. CRTCs that require a
 	 * mode set are disabled prior plane updates and enabled afterwards.
@@ -418,13 +410,14 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
 
 	DBG("%s: GO", omap_crtc->name);
 
+	dispc_mgr_go(omap_crtc->channel);
+
+	WARN_ON(drm_crtc_vblank_get(crtc) != 0);
+
 	spin_lock_irq(&crtc->dev->event_lock);
 	WARN_ON(omap_crtc->pending);
 	omap_crtc->pending = true;
 	spin_unlock_irq(&crtc->dev->event_lock);
-
-	dispc_mgr_go(omap_crtc->channel);
-	omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);
 }
 
 static bool omap_crtc_is_plane_prop(struct drm_device *dev,
@@ -546,9 +539,6 @@ struct drm_crtc *omap_crtc_init(struct drm_device *dev,
 	omap_crtc->channel = channel;
 	omap_crtc->name = channel_names[channel];
 
-	omap_crtc->vblank_irq.irqmask = pipe2vbl(crtc);
-	omap_crtc->vblank_irq.irq = omap_crtc_vblank_irq;
-
 	ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
 					&omap_crtc_funcs, NULL);
 	if (ret < 0) {
diff --git a/drivers/gpu/drm/omapdrm/omap_drv.h b/drivers/gpu/drm/omapdrm/omap_drv.h
index 17dd3b98fc1a..d5f27d117b6a 100644
--- a/drivers/gpu/drm/omapdrm/omap_drv.h
+++ b/drivers/gpu/drm/omapdrm/omap_drv.h
@@ -156,6 +156,7 @@ struct drm_crtc *omap_crtc_init(struct drm_device *dev,
 		struct drm_plane *plane, enum omap_channel channel, int id);
 int omap_crtc_wait_pending(struct drm_crtc *crtc);
 void omap_crtc_error_irq(struct drm_crtc *crtc, uint32_t irqstatus);
+void omap_crtc_vblank_irq(struct drm_crtc *crtc);
 
 struct drm_plane *omap_plane_init(struct drm_device *dev,
 		int id, enum drm_plane_type type);
diff --git a/drivers/gpu/drm/omapdrm/omap_irq.c b/drivers/gpu/drm/omapdrm/omap_irq.c
index 499da6e2c5a4..b2e3fd78f7e0 100644
--- a/drivers/gpu/drm/omapdrm/omap_irq.c
+++ b/drivers/gpu/drm/omapdrm/omap_irq.c
@@ -240,8 +240,10 @@ static irqreturn_t omap_irq_handler(int irq, void *arg)
 		struct drm_crtc *crtc = priv->crtcs[id];
 		enum omap_channel channel = omap_crtc_channel(crtc);
 
-		if (irqstatus & pipe2vbl(crtc))
+		if (irqstatus & pipe2vbl(crtc)) {
 			drm_handle_vblank(dev, id);
+			omap_crtc_vblank_irq(crtc);
+		}
 
 		if (irqstatus & dispc_mgr_get_sync_lost_irq(channel))
 			omap_crtc_error_irq(crtc, irqstatus);
-- 
2.7.3