After disabling and reenabling the CRTC the DCU sometimes got stuck
displaying the whole screen with a solid color. Disabling and
reenabling the CRTC did not recover from the situation. This was
often reproducable by just restarting the X-Server.
The disabling sequence is not explicitly documented. But it turns
out that disabling the planes before disabling the CRTC seems to
prevent the above situation from happening.
Use the callback ->atomic_disable instead of ->disable which allows
to use the drm_atomic_helper_disable_planes_on_crtc() helper to
disable planes before disabling the controller.
Signed-off-by: Stefan Agner <stefan at agner.ch>
---
drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
index 2ea9dbd..deb5743 100644
--- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
+++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_crtc.c
@@ -44,11 +44,15 @@ static void fsl_dcu_drm_crtc_atomic_flush(struct drm_crtc
*crtc,
}
}
-static void fsl_dcu_drm_disable_crtc(struct drm_crtc *crtc)
+static void fsl_dcu_drm_crtc_atomic_disable(struct drm_crtc *crtc,
+ struct drm_crtc_state *old_crtc_state)
{
struct drm_device *dev = crtc->dev;
struct fsl_dcu_drm_device *fsl_dev = dev->dev_private;
+ /* always disable planes on the CRTC */
+ drm_atomic_helper_disable_planes_on_crtc(old_crtc_state, true);
+
drm_crtc_vblank_off(crtc);
regmap_update_bits(fsl_dev->regmap, DCU_DCU_MODE,
@@ -127,8 +131,8 @@ static void fsl_dcu_drm_crtc_mode_set_nofb(struct drm_crtc
*crtc)
}
static const struct drm_crtc_helper_funcs fsl_dcu_drm_crtc_helper_funcs = {
+ .atomic_disable = fsl_dcu_drm_crtc_atomic_disable,
.atomic_flush = fsl_dcu_drm_crtc_atomic_flush,
- .disable = fsl_dcu_drm_disable_crtc,
.enable = fsl_dcu_drm_crtc_enable,
.mode_set_nofb = fsl_dcu_drm_crtc_mode_set_nofb,
};
--
2.10.0
