As per the docs, atomic_commit should return -EBUSY "if an asycnhronous updated is requested and there is an earlier updated pending".

v2: Use the status of the workqueue instead of vop->event, and don't add a superfluous wait on the workqueue.

v3: Drop work_busy, as there's a sizeable delay when the worker finishes, which introduces a race in which the client has already received the last flip event but the next page flip ioctl will still return -EBUSY because work_busy returns outdated information.

Signed-off-by: Tomeu Vizoso tomeu.vizoso@collabora.com --- drivers/gpu/drm/rockchip/rockchip_drm_drv.h | 1 + drivers/gpu/drm/rockchip/rockchip_drm_fb.c | 13 ++++++++++++- drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 5 +++++ 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h index 3529f692edb8..37952eefd33d 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.h +++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.h @@ -69,6 +69,7 @@ int rockchip_register_crtc_funcs(struct drm_crtc *crtc, void rockchip_unregister_crtc_funcs(struct drm_crtc *crtc); int rockchip_drm_crtc_mode_config(struct drm_crtc *crtc, int connector_type, int out_mode); +bool rockchip_drm_crtc_has_pending_event(struct drm_crtc *crtc); int rockchip_drm_dma_attach_device(struct drm_device *drm_dev, struct device *dev); void rockchip_drm_dma_detach_device(struct drm_device *drm_dev, diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c index 3b8f652698f8..8305bbd2a4d7 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c @@ -280,7 +280,18 @@ int rockchip_drm_atomic_commit(struct drm_device *dev, { struct rockchip_drm_private *private = dev->dev_private; struct rockchip_atomic_commit *commit = &private->commit; - int ret; + struct drm_crtc_state *crtc_state; + struct drm_crtc *crtc; + int i, ret; + + if (async) { + for_each_crtc_in_state(state, crtc, crtc_state, i) { + if (crtc->state->event || + rockchip_drm_crtc_has_pending_event(crtc)) { + return -EBUSY; + } + } + }

ret = drm_atomic_helper_prepare_planes(dev, state); if (ret) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c index e2118e62345b..5bcdd8dc7499 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c @@ -848,6 +848,11 @@ int rockchip_drm_crtc_mode_config(struct drm_crtc *crtc, } EXPORT_SYMBOL_GPL(rockchip_drm_crtc_mode_config);

+bool rockchip_drm_crtc_has_pending_event(struct drm_crtc *crtc) +{ + return to_vop(crtc)->event; +} + static int vop_crtc_enable_vblank(struct drm_crtc *crtc) { struct vop *vop = to_vop(crtc);