Implement atomic_flush, atomic_enable and atomic_disable of struct
drm_crtc_helper_funcs for vblank handling. Driver with no further
requirements can use these functions instead of adding their own.
Also simplifies the use of vblank timers.
v2:
- fix docs
Signed-off-by: Thomas Zimmermann <tzimmerm...@suse.de>
---
drivers/gpu/drm/drm_vblank_helper.c | 80 +++++++++++++++++++++++++++++
include/drm/drm_vblank_helper.h | 23 +++++++++
2 files changed, 103 insertions(+)
diff --git a/drivers/gpu/drm/drm_vblank_helper.c
b/drivers/gpu/drm/drm_vblank_helper.c
index f94d1e706191..a04a6ba1b0ca 100644
--- a/drivers/gpu/drm/drm_vblank_helper.c
+++ b/drivers/gpu/drm/drm_vblank_helper.c
@@ -1,5 +1,6 @@
// SPDX-License-Identifier: MIT
+#include <drm/drm_atomic.h>
#include <drm/drm_crtc.h>
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper_vtables.h>
@@ -17,6 +18,12 @@
* Drivers enable support for vblank timers by setting the vblank callbacks
* in struct &drm_crtc_funcs to the helpers provided by this library. The
* initializer macro DRM_CRTC_VBLANK_TIMER_FUNCS does this conveniently.
+ * The driver further has to send the VBLANK event from its atomic_flush
+ * callback and control vblank from the CRTC's atomic_enable and atomic_disable
+ * callbacks. The callbacks are located in struct &drm_crtc_helper_funcs.
+ * The vblank helper library provides implementations of these callbacks
+ * for drivers without further requirements. The initializer macro
+ * DRM_CRTC_HELPER_VBLANK_FUNCS sets them coveniently.
*
* Once the driver enables vblank support with drm_vblank_init(), each
* CRTC's vblank timer fires according to the programmed display mode. By
@@ -25,6 +32,79 @@
* struct &drm_crtc_helper_funcs.handle_vblank_timeout.
*/
+/*
+ * VBLANK helpers
+ */
+
+/**
+ * drm_crtc_vblank_atomic_flush -
+ * Implements struct &drm_crtc_helper_funcs.atomic_flush
+ * @crtc: The CRTC
+ * @state: The atomic state to apply
+ *
+ * The helper drm_crtc_vblank_atomic_flush() implements atomic_flush of
+ * struct drm_crtc_helper_funcs for CRTCs that only need to send out a
+ * VBLANK event.
+ *
+ * See also struct &drm_crtc_helper_funcs.atomic_flush.
+ */
+void drm_crtc_vblank_atomic_flush(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_crtc_state *crtc_state =
drm_atomic_get_new_crtc_state(state, crtc);
+ struct drm_pending_vblank_event *event;
+
+ spin_lock_irq(&dev->event_lock);
+
+ event = crtc_state->event;
+ crtc_state->event = NULL;
+
+ if (event) {
+ if (drm_crtc_vblank_get(crtc) == 0)
+ drm_crtc_arm_vblank_event(crtc, event);
+ else
+ drm_crtc_send_vblank_event(crtc, event);
+ }
+
+ spin_unlock_irq(&dev->event_lock);
+}
+EXPORT_SYMBOL(drm_crtc_vblank_atomic_flush);
+
+/**
+ * drm_crtc_vblank_atomic_enable - Implements struct
&drm_crtc_helper_funcs.atomic_enable
+ * @crtc: The CRTC
+ * @state: The atomic state
+ *
+ * The helper drm_crtc_vblank_atomic_enable() implements atomic_enable
+ * of struct drm_crtc_helper_funcs for CRTCs the only need to enable VBLANKs.
+ *
+ * See also struct &drm_crtc_helper_funcs.atomic_enable.
+ */
+void drm_crtc_vblank_atomic_enable(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ drm_crtc_vblank_on(crtc);
+}
+EXPORT_SYMBOL(drm_crtc_vblank_atomic_enable);
+
+/**
+ * drm_crtc_vblank_atomic_disable - Implements struct
&drm_crtc_helper_funcs.atomic_disable
+ * @crtc: The CRTC
+ * @state: The atomic state
+ *
+ * The helper drm_crtc_vblank_atomic_disable() implements atomic_disable
+ * of struct drm_crtc_helper_funcs for CRTCs the only need to disable VBLANKs.
+ *
+ * See also struct &drm_crtc_funcs.atomic_disable.
+ */
+void drm_crtc_vblank_atomic_disable(struct drm_crtc *crtc,
+ struct drm_atomic_state *state)
+{
+ drm_crtc_vblank_off(crtc);
+}
+EXPORT_SYMBOL(drm_crtc_vblank_atomic_disable);
+
/*
* VBLANK timer
*/
diff --git a/include/drm/drm_vblank_helper.h b/include/drm/drm_vblank_helper.h
index 74a971d0cfba..fcd8a9b35846 100644
--- a/include/drm/drm_vblank_helper.h
+++ b/include/drm/drm_vblank_helper.h
@@ -6,8 +6,31 @@
#include <linux/hrtimer_types.h>
#include <linux/types.h>
+struct drm_atomic_state;
struct drm_crtc;
+/*
+ * VBLANK helpers
+ */
+
+void drm_crtc_vblank_atomic_flush(struct drm_crtc *crtc,
+ struct drm_atomic_state *state);
+void drm_crtc_vblank_atomic_enable(struct drm_crtc *crtc,
+ struct drm_atomic_state *state);
+void drm_crtc_vblank_atomic_disable(struct drm_crtc *crtc,
+ struct drm_atomic_state *crtc_state);
+
+/**
+ * DRM_CRTC_HELPER_VBLANK_FUNCS - Default implementation for VBLANK helpers
+ *
+ * This macro initializes struct &drm_crtc_helper_funcs to default helpers
+ * for VBLANK handling.
+ */
+#define DRM_CRTC_HELPER_VBLANK_FUNCS \
+ .atomic_flush = drm_crtc_vblank_atomic_flush, \
+ .atomic_enable = drm_crtc_vblank_atomic_enable, \
+ .atomic_disable = drm_crtc_vblank_atomic_disable
+
/*
* VBLANK timer
*/
--
2.50.1
