drm/vc4: hvs: Ignore atomic_flush if we're disabled

atomic_flush will be called for each CRTC even if they aren't enabled.

The whole code we have there will thus run without a properly affected
channel, which can then result in all sorts of weird behaviour.

Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20221207-rpi-hvs-crtc-misc-v1-8-1f8e0770798b@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 260efd44a821899e69742d90611f1f711ddb3076..4da66ef9678354ffa6645a035efa5a8fc0f4ddac 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -579,6 +579,9 @@ void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
                return;
        }
 
+       if (vc4_state->assigned_channel == VC4_HVS_CHANNEL_DISABLED)
+               return;
+
        if (debug_dump_regs) {
                DRM_INFO("CRTC %d HVS before:\n", drm_crtc_index(crtc));
                vc4_hvs_dump_state(hvs);