drm/msm: dpu: Add modeset lock checks where applicable

Add modeset lock checks to functions that could be called outside the
core atomic stack.

Changes in v2:
- None
Reviewed-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c

@@ -284,6 +284,8 @@ enum dpu_intf_mode dpu_crtc_get_intf_mode(struct drm_crtc *crtc)
 		return INTF_MODE_NONE;
 	}
 
+	WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
+
 	/* TODO: Returns the first INTF_MODE, could there be multiple values? */
 	drm_for_each_encoder_mask(encoder, crtc->dev, crtc->state->encoder_mask)
 		return dpu_encoder_get_intf_mode(encoder);

drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c

@@ -358,6 +358,7 @@ void dpu_kms_encoder_enable(struct drm_encoder *encoder)
 	if (funcs && funcs->commit)
 		funcs->commit(encoder);
 
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	drm_for_each_crtc(crtc, dev) {
 		if (!(crtc->state->encoder_mask & drm_encoder_mask(encoder)))
 			continue;